Electrical device system and battery pack

Abstract

This electrical device system comprises a first battery pack, a second battery pack, and an electrical device. The electrical device is provided with a battery pack attachment part. The first battery pack is provided with three first battery cells electrically connected in series. The first battery cell is a tabless battery cell. The DC internal resistance of the first battery cell is in the range of 5-20 mΩ. The rated voltage of the first battery pack is in the range of 9.72-11.88 V. The second battery pack is provided with three second battery cells electrically connected in series. The second battery cell is a tab-type battery cell. The DC internal resistance of the second battery cell is in the range of 21-50 mΩ. The rated voltage of the second battery pack is in the range of 9.72-11.88 V.

Description

Electrical equipment system and battery pack

[0001] The technology disclosed in this specification relates to an electrical equipment system and a battery pack.

[0002] Japanese Patent Application Laid-Open No. 2018-64659 discloses an electrical equipment system. The electrical equipment system includes a battery pack and electrical equipment. The electrical equipment includes a battery pack attachment portion to which the battery pack can be detachably attached. The battery pack includes three battery cells electrically connected in series. The rated voltage of the battery pack is 10.8 [V].

[0003] In recent years, there has been a demand to increase the output of battery packs with a rated voltage in the range of 9.72 [V] - 11.88 [V]. This specification provides a technology capable of increasing the output in a battery pack with a rated voltage in the range of 9.72 [V] - 11.88 [V].

[0004] The electrical equipment system disclosed in this specification may include a first battery pack, a second battery pack, and electrical equipment. The electrical equipment may include a battery pack attachment portion that can selectively attach and detach the first battery pack or the second battery pack. The first battery pack may include three first battery cells electrically connected in series. The first battery cell may have a cylindrical shape. The diameter of the first battery cell may be in the range of 17 [mm] - 20 [mm]. The first battery cell may be a tabless type battery cell. The DC internal resistance of the first battery cell may be in the range of 5 [mΩ] - 20 [mΩ]. The rated voltage of the first battery pack may be in the range of 9.72 [V] - 11.88 [V]. The second battery pack may include three second battery cells electrically connected in series. The second battery cell may have a cylindrical shape. The diameter of the second battery cell may be in the range of 17 [mm] - 20 [mm]. The second battery cell may be a tab type battery cell. The DC internal resistance of the second battery cell may be in the range of 21 [mΩ] - 50 [mΩ]. The rated voltage of the second battery pack may be in the range of 9.72 [V] - 11.88 [V].

[0005] According to the above configuration, the first battery cell in the first battery pack is a tablet-type battery cell with a DC internal resistance of 5 mΩ to 20 mΩ, so the output of the first battery pack is relatively large. For this reason, the output can be further increased for the first battery pack whose rated voltage is in the range of 9.72 V to 11.88 V.

[0006] Furthermore, according to the above configuration, the second battery cell in the second battery pack is a tab-type battery cell with a DC internal resistance of 21 mΩ to 50 mΩ, so the output of the second battery pack is relatively small. For this reason, the electrical equipment can selectively use either the first battery pack, which has a rated voltage in the range of 9.72 V to 11.88 V and a relatively large output, or the second battery pack, which has a rated voltage in the range of 9.72 V to 11.88 V and a relatively small output.

[0007] The battery pack disclosed herein may comprise three battery cells electrically connected in series. The battery cells may have a cylindrical shape. The diameter of the battery cells may be in the range of 17 mm to 20 mm. The battery cells may be of the tablet type. The DC internal resistance of the battery cells may be in the range of 5 mΩ to 20 mΩ. The rated voltage of the battery pack may be in the range of 9.72 V to 11.88 V.

[0008] According to the above configuration, the battery cells in the battery pack are tablet-type battery cells with a DC internal resistance of 5 mΩ to 20 mΩ, resulting in a relatively high output from the battery pack. Therefore, the output can be further increased for battery packs with a rated voltage in the range of 9.72 V to 11.88 V.

[0009] Another electrical equipment system disclosed herein may comprise a first battery pack, a second battery pack, and an electrical device. The electrical device may include a battery pack mounting section to which the first battery pack or the second battery pack can be selectively attached or detached. The first battery pack may comprise three first battery cells electrically connected in series. The first battery cells may have a cylindrical shape. The diameter of the first battery cells may be in the range of 21 mm to 23 mm. The first battery cells may be tablet-type battery cells. The DC internal resistance of the first battery cells may be in the range of 5 mΩ to 15 mΩ. The rated voltage of the first battery pack may be in the range of 9.72 V to 11.88 V. The second battery pack may comprise three second battery cells electrically connected in series. The second battery cells may have a cylindrical shape. The diameter of the second battery cells may be in the range of 21 mm to 23 mm. The second battery cell may be a tab-type battery cell. The DC internal resistance of the second battery cell may be in the range of 16 [mΩ] to 50 [mΩ]. The rated voltage of the second battery pack may be in the range of 9.72 [V] to 11.88 [V].

[0010] According to the above configuration, the first battery cell in the first battery pack is a tablet-type battery cell with a DC internal resistance of 5 mΩ to 15 mΩ, so the output of the first battery pack is relatively large. For this reason, the output can be further increased for the first battery pack whose rated voltage is in the range of 9.72 V to 11.88 V.

[0011] Furthermore, according to the above configuration, the second battery cell in the second battery pack is a tab-type battery cell with a DC internal resistance of 16 mΩ to 50 mΩ, so the output of the second battery pack is relatively small. For this reason, the electrical equipment can selectively use either the first battery pack, which has a rated voltage in the range of 9.72 V to 11.88 V and a relatively large output, or the second battery pack, which has a rated voltage in the range of 9.72 V to 11.88 V and a relatively small output.

[0012] Another battery pack disclosed herein may comprise three battery cells electrically connected in series. The battery cells may have a cylindrical shape. The diameter of the battery cells may be in the range of 21 mm to 23 mm. The battery cells may be of the tablet type. The DC internal resistance of the battery cells may be in the range of 5 mΩ to 15 mΩ. The rated voltage of the battery pack may be in the range of 9.72 V to 11.88 V.

[0013] According to the above configuration, the battery cells in the battery pack are tablet-type battery cells with a DC internal resistance of 5 mΩ to 15 mΩ, resulting in a relatively high output from the battery pack. Therefore, the output can be further increased for battery packs with a rated voltage in the range of 9.72 V to 11.88 V.

[0014] This is a schematic diagram showing the configuration of the electrical equipment system 2 of Example 1. This is a perspective view of the electrical equipment 10 and battery packs 12 and 14 of Example 1. This is a perspective view of the electrical equipment 10 and battery packs 16 and 18 of Example 1. This is a longitudinal cross-sectional view of the battery packs 12 and 14 of Example 1. This is a perspective view of the battery cells 40, 42, and 44, the cell holder 46, the circuit board 48, the lead plate 49, and the battery-side terminals 50 of the battery packs 12 and 14 of Example 1. This is a perspective view of the battery packs 12 and 14 of Example 1. This is a perspective view of the battery cells 40 and 100 of Example 1. This is a schematic diagram showing the configuration of the multilayer sheet 82 in the battery cell 40 of Example 1. This is a top view of the battery packs 12 and 14 of Example 1 with the upper casing 56 removed. This is a schematic diagram showing the configuration of the multilayer sheet 114 in the battery cell 100 of Example 1. This is a longitudinal cross-sectional view of the battery packs 16 and 18 of Example 1. This is a perspective view of the battery cells 126, 128, 130, 132, 134, 136, cell holder 138, circuit board 140, lead plate 141, and battery-side terminal 142 of the battery packs 16 and 18 of Example 1. This is a perspective view of the battery packs 16 and 18 of Example 1. This is a top view of the battery packs 16 and 18 of Example 1 with the upper casing 154 removed. This is a schematic diagram showing the configuration of the electrical equipment system 202 of Example 2. This is a perspective view of the electrical equipment 210 and battery packs 212 and 214 of Example 2. This is a perspective view of the electrical equipment 210 and battery packs 216 and 218 of Example 2. This is a perspective view of the battery pack mounting portion 220 of the electrical equipment 210 of Example 2. This is a longitudinal cross-sectional view of the battery packs 212 and 214 of Example 2. This is a perspective view of the battery cells 236, 238, 240, cell holder 242, circuit board 244, lead plate 245, and battery-side terminal 246 of the battery packs 212, 214 of Example 2. This is a perspective view of the battery packs 212, 214 of Example 2. This is a top view of the battery packs 212, 214 of Example 2 with the upper casing 252 removed. This is a perspective view of the battery packs 216, 218 of Example 2. This is a cross-sectional view of the insertion projection 254 of the battery packs 216, 218 of Example 2. This is a cross-sectional view of the battery cell housing portion 304 of the battery packs 216, 218 of Example 2. This is a schematic diagram showing the configuration of the electrical equipment system 402 of Example 3. This is a perspective view of the electrical equipment 404 and battery packs 406, 408 of Example 3.This is a perspective view of the electrical equipment 404 and battery packs 410 and 412 of Example 3. This is a longitudinal cross-sectional view of the battery packs 406 and 408 of Example 3. This is a perspective view of the battery packs 406 and 408 of Example 3. This is a top view of the battery packs 406 and 408 of Example 3 with the upper casing 430 removed. This is a longitudinal cross-sectional view of the battery packs 410 and 412 of Example 3. This is a perspective view of the battery packs 410 and 412 of Example 3. This is a top view of the battery packs 410 and 412 of Example 3 with the upper casing 482 removed. This is a schematic diagram showing the configuration of the electrical equipment system 602 of Example 4. This is a perspective view of the electrical equipment 604 and battery packs 606 and 608 of Example 4. This is a perspective view of the electrical equipment 604 and battery packs 610 and 612 of Example 4. This is a perspective view of the battery pack mounting portion 614 of the electrical equipment 604 of Example 4. This is a longitudinal cross-sectional view of the battery packs 606 and 608 of Example 4. This is a perspective view of the battery cells 636, 638, cell holder 640, lead plate 642, and battery-side terminal 644 of the battery packs 606, 608 of Example 4. This is a perspective view of the battery packs 606, 608 of Example 4. This is a cross-sectional view of the insertion projection 652 of the battery packs 606, 608 of Example 4. This is a perspective view of the battery packs 610, 612 of Example 4. This is a rear view of the battery packs 610, 612 of Example 4. This is a diagram showing an example of the circuit configuration of the battery packs 12, 14 and electrical equipment 10 of Example 1. This is a diagram showing an example of the circuit configuration of the battery packs 16, 18 and electrical equipment 10 of Example 1. This is a diagram showing an example of the circuit configuration of the battery packs 212, 214 and electrical equipment 210 of Example 2. This is a diagram showing an example of the circuit configuration of the battery packs 216, 218 and electrical equipment 210 of Example 2. This is a diagram showing an example of the circuit configuration of the battery packs 406, 408 and electrical equipment 404 of Example 3. This figure shows an example of the circuit configuration of the battery packs 410 and 412 and the electrical device 404 in Example 3. This figure shows an example of the circuit configuration of the battery packs 606 and 608 and the electrical device 604 in Example 4. This figure shows an example of the circuit configuration of the battery packs 610 and 612 and the electrical device 604 in Example 4.

[0015] Representative and non-limiting examples of the present invention are described in detail below with reference to the drawings. This detailed description is intended simply to show those skilled in the art details for carrying out preferred examples of the present invention and is not intended to limit the scope of the invention. Furthermore, the disclosed additional features and inventions can be used separately from or in conjunction with other features and inventions to provide further improved electrical equipment systems and battery packs.

[0016] Furthermore, the combinations of features and processes disclosed in the following detailed description are not essential for carrying out the present invention in the broadest sense, and are described solely to illustrate representative examples of the present invention. Moreover, the various features of the following representative examples, as well as the various features described in the claims, do not necessarily have to be combined in the same way as the examples described herein, or in the order listed, to provide additional and useful embodiments of the present invention.

[0017] All features described herein and / or in the claims are intended to be disclosed individually and independently of each other, as limitations to the specific matters described in the original disclosure and in the claims, separate from the features described in the examples and / or in the claims. Furthermore, all descriptions of numerical ranges and groups or clusters are intended to disclose intermediate configurations as limitations to the specific matters described in the original disclosure and in the claims.

[0018] In one or more embodiments, the electrical equipment system may comprise a first battery pack, a second battery pack, and an electrical device. The electrical device may include a battery pack mounting section to which the first battery pack or the second battery pack can be selectively attached or detached. The first battery pack may comprise three first battery cells electrically connected in series. The first battery cells may have a cylindrical shape. The diameter of the first battery cells may be in the range of 17 mm to 20 mm. The first battery cells may be tablet-type battery cells. The DC internal resistance of the first battery cells may be in the range of 5 mΩ to 20 mΩ. The rated voltage of the first battery pack may be in the range of 9.72 V to 11.88 V. The second battery pack may comprise three second battery cells electrically connected in series. The second battery cells may have a cylindrical shape. The diameter of the second battery cells may be in the range of 17 mm to 20 mm. The second battery cell may be a tab-type battery cell. The DC internal resistance of the second battery cell may be in the range of 21 [mΩ] to 50 [mΩ]. The rated voltage of the second battery pack may be in the range of 9.72 [V] to 11.88 [V].

[0019] In one or more embodiments, the diameter of the first battery cell may be in the range of 17 mm to 19 mm. The diameter of the second battery cell may be in the range of 17 mm to 19 mm.

[0020] In one or more embodiments, the height of the first battery cell may be in the range of 64 mm to 67 mm. The height of the second battery cell may be in the range of 64 mm to 67 mm.

[0021] In one or more embodiments, the weight of the first battery cell may be in the range of 40 g to 50 g. The weight of the second battery cell may be in the range of 40 g to 50 g.

[0022] In one or more embodiments, the rated capacity of the first battery cell may be in the range of 2.0 [Ah] to 6.0 [Ah]. The rated capacity of the second battery cell may be in the range of 2.0 [Ah] to 6.0 [Ah]. In this specification, the rated capacity defined in ampere-hours is simply referred to as "rated capacity," and the rated capacity defined in watt-hours is referred to as "energy capacity."

[0023] In one or more embodiments, the rated capacity of the first battery pack may be in the range of 2.0 [Ah] to 6.0 [Ah]. The rated capacity of the second battery pack may be in the range of 2.0 [Ah] to 6.0 [Ah].

[0024] In one or more embodiments, the first battery pack may be a slide-type battery pack. The second battery pack may also be a slide-type battery pack.

[0025] In one or more embodiments, the weight of the first battery pack may be in the range of 180 g to 270 g. The weight of the second battery pack may be in the range of 180 g to 270 g.

[0026] In one or more embodiments, the first battery pack may be a stick-type battery pack. The second battery pack may be a stick-type battery pack.

[0027] In one or more embodiments, the weight of the first battery pack may be 150 g to 240 g. The weight of the second battery pack may be 150 g to 240 g.

[0028] In one or more embodiments, the first battery pack may comprise three further first battery cells electrically connected in series. The second battery pack may comprise three further second battery cells electrically connected in series.

[0029] In one or more embodiments, the rated capacity of the first battery pack may be in the range of 4.0 [Ah] to 12.0 [Ah]. The rated capacity of the second battery pack may be in the range of 4.0 [Ah] to 12.0 [Ah].

[0030] In one or more embodiments, the first battery pack may be a slide-type battery pack. The second battery pack may also be a slide-type battery pack.

[0031] In one or more embodiments, the weight of the first battery pack may be 330 g to 480 g. The weight of the second battery pack may be 330 g to 480 g.

[0032] In one or more embodiments, the first battery pack may be a stick-type battery pack. The second battery pack may be a stick-type battery pack.

[0033] In one or more embodiments, the weight of the first battery pack may be in the range of 370 g to 500 g. The weight of the second battery pack may be in the range of 370 g to 500 g.

[0034] In one or more embodiments, the battery pack may comprise three battery cells electrically connected in series. The battery cells may have a cylindrical shape. The diameter of the battery cells may be in the range of 17 mm to 20 mm. The battery cells may be tablet-type battery cells. The DC internal resistance of the battery cells may be in the range of 5 mΩ to 20 mΩ. The rated voltage of the battery pack may be in the range of 9.72 V to 11.88 V.

[0035] In one or more embodiments, the electrical equipment system may comprise a first battery pack, a second battery pack, and an electrical device. The electrical device may include a battery pack mounting section to which the first battery pack or the second battery pack can be selectively attached or detached. The first battery pack may comprise three first battery cells electrically connected in series. The first battery cells may have a cylindrical shape. The diameter of the first battery cells may be in the range of 21 mm to 23 mm. The first battery cells may be tablet-type battery cells. The DC internal resistance of the first battery cells may be in the range of 5 mΩ to 15 mΩ. The rated voltage of the first battery pack may be in the range of 9.72 V to 11.88 V. The second battery pack may comprise three second battery cells electrically connected in series. The second battery cells may have a cylindrical shape. The diameter of the second battery cells may be in the range of 21 mm to 23 mm. The second battery cell may be a tab-type battery cell. The DC internal resistance of the second battery cell may be in the range of 16 [mΩ] to 50 [mΩ]. The rated voltage of the second battery pack may be in the range of 9.72 [V] to 11.88 [V].

[0036] In one or more embodiments, the diameter of the first battery cell may be in the range of 21 mm to 22 mm. The diameter of the second battery cell may be in the range of 21 mm to 22 mm.

[0037] In one or more embodiments, the height of the first battery cell may be in the range of 70 mm to 72 mm. The height of the second battery cell may be in the range of 70 mm to 72 mm.

[0038] In one or more embodiments, the weight of the first battery cell may be in the range of 65 g to 75 g. The weight of the second battery cell may be in the range of 65 g to 75 g.

[0039] In one or more embodiments, the rated capacity of the first battery cell may be within the range of 2.0 [Ah] - 6.0 [Ah]. The rated capacity of the second battery cell may be within the range of 2.0 [Ah] - 6.0 [Ah].

[0040] In one or more embodiments, the rated capacity of the first battery pack may be within the range of 2.0 [Ah] - 6.0 [Ah]. The rated capacity of the second battery pack may be within the range of 2.0 [Ah] - 6.0 [Ah].

[0041] In one or more embodiments, the first battery pack may be a slide-type battery pack. The second battery pack may be a slide-type battery pack.

[0042] In one or more embodiments, the weight of the first battery pack may be within the range of 270 [g] - 380 [g]. The weight of the second battery pack may be within the range of 270 [g] - 380 [g].

[0043] In one or more embodiments, the first battery pack may further include three first battery cells electrically connected in series. The second battery pack may further include three second battery cells electrically connected in series.

[0044] In one or more embodiments, the rated capacity of the first battery pack may be within the range of 4.0 [Ah] - 12.0 [Ah]. The rated capacity of the second battery pack may be within the range of 4.0 [Ah] - 12.0 [Ah].

[0045] In one or more embodiments, the first battery pack may be a slide-type battery pack. The second battery pack may be a slide-type battery pack.

[0046] In one or more embodiments, the weight of the first battery pack may be 450 [g] - 630 [g]. The weight of the second battery pack may be 450 [g] - 630 [g].

[0047] In one or more embodiments, the battery pack may include three battery cells electrically connected in series. The battery cell may have a cylindrical shape. The diameter of the battery cell may be in the range of 21 [mm] - 23 [mm]. The battery cell may be a tabless type battery cell. The DC internal resistance of the battery cell may be in the range of 5 [mΩ] - 15 [mΩ]. The rated voltage of the battery pack may be in the range of 9.72 [V] - 11.88 [V].

[0048] (Example 1) As shown in FIG. 1, the electric equipment system 2 of this example includes an electric equipment 10 and battery packs 12, 14, 16, 18. Any one of the battery packs 12, 14, 16, 18 can be selectively attached to the electric equipment 10. The electric equipment 10 is an electric equipment that operates using the power supplied from the battery packs 12, 14, 16, 18. The electric equipment 10 may be, for example, a power tool powered by a motor, such as a driver drill or an impact driver, or an electric working machine powered by a motor, such as a hedge trimmer or a handy saw. Alternatively, the electric equipment 10 may be an electric equipment without a motor, such as a light, a radio, or a speaker. Alternatively, the electric equipment 10 may be a charger that charges the battery packs 12, 14, 16, 18.

[0049] (Configuration of the electrical device 10) As shown in Figures 2 and 3, the electrical device 10 is equipped with a battery pack mounting section 20. The battery packs 12, 14, 16, and 18 can be attached to the battery pack mounting section 20 by sliding them in a predetermined sliding direction relative to the battery pack mounting section 20. In other words, the battery packs 12, 14, 16, and 18 are slide-type battery packs. Hereinafter, the direction in which the battery packs 12, 14, 16, and 18 are slid when attaching them to the battery pack mounting section 20 will be referred to as the rear direction, and the direction in which the battery packs 12, 14, 16, and 18 are slid when removing them from the battery pack mounting section 20 will be referred to as the front direction. Furthermore, with the battery packs 12, 14, 16, and 18 attached to the battery pack mounting section 20, the direction in which the battery pack mounting section 20 is located relative to the battery packs 12, 14, 16, and 18 is referred to as the upward direction, and the opposite direction to the upward direction is referred to as the downward direction. In addition, the direction perpendicular to the front-back direction and the up-down direction is referred to as the left-right direction.

[0050] The battery pack mounting section 20 is provided with a device-side terminal 22, a device-side rail 24, and an engagement groove 26. The device-side terminal 22 includes a positive power terminal 28 and a negative power terminal 30 for charging or discharging power between the electrical device 10 and the battery packs 12, 14, 16, and 18, and a signal communication terminal 32 for signal communication between the electrical device 10 and the battery packs 12, 14, 16, and 18. In the example shown in Figures 2 and 3, only one signal communication terminal 32 is shown, but the number of signal communication terminals 32 is not limited to one, and the electrical device 10 may have two or more signal communication terminals 32. The device-side rail 24 includes a right-side rail 34 that extends in the front-rear direction to the right of the device-side terminal 22, and a left-side rail 36 that extends in the front-rear direction to the left of the device-side terminal 22. The right-side rail 34 and the left-side rail 36 are formed at the lower end of the housing 38 of the electrical device 10. The engagement groove 26 is formed in the housing 38 in front of the equipment-side terminal 22 and is recessed upwards.

[0051] (Configuration of Battery Pack 12) As shown in Figure 4, the battery pack 12 comprises battery cells 40, 42, 44 (see Figure 5), a cell holder 46, a circuit board 48, a lead plate 49, battery-side terminals 50, and a casing 52. As shown in Figure 5, the battery cells 40, 42, 44 are arranged in a row, one vertically and three horizontally, with their longitudinal direction aligned with the front-to-back direction. The battery cells 40, 42, 44 are electrically connected in series via the lead plate 49. The cell holder 46 holds the battery cells 40, 42, 44. The circuit board 48 is held by the cell holder 46 above it and is electrically connected to the battery cells 40, 42, 44 via the lead plate 49. The battery-side terminals 50 are provided on the circuit board 48. As shown in Figure 4, the casing 52 houses the battery cells 40, 42, 44, the cell holder 46, the circuit board 48, the lead plate 49, and the battery-side terminals 50.

[0052] As shown in Figure 6, the casing 52 comprises a lower casing 54 and an upper casing 56. The upper casing 56 has a terminal opening 58 and a battery-side rail 60. The terminal opening 58 is positioned to correspond to the device-side terminals 22 (see Figure 2) of the electrical device 10. The terminal opening 58 has a shape that allows the device-side terminals 22 to pass through when the battery pack 12 is attached to the electrical device 10. The battery-side rail 60 comprises a right-side rail 62 that extends along the front-rear direction to the right of the terminal opening 58 and a left-side rail 64 that extends along the front-rear direction to the left of the terminal opening 58. The right-side rail 62 and the left-side rail 64 engage with the right-side rail 34 and the left-side rail 36 (see Figure 2) of the electrical device 10 so as to be movable in the front-rear direction when the battery pack 12 is attached to the electrical device 10.

[0053] A hook 66 is attached to the upper casing 56. The hook 66 has an engaging portion 68 and an operating portion 70. As shown in Figure 4, the hook 66 is biased upward by a compression spring 72. When the battery pack 12 is attached to the electrical device 10, the engaging portion 68 of the hook 66 fits into the engaging groove 26 (see Figure 2) of the electrical device 10, thereby fixing the battery pack 12 to the electrical device 10. From this state, when the user pushes down the operating portion 70 of the hook 66, the engaging portion 68 disengages from the engaging groove 26. In this state, the user can slide the battery pack 12 forward relative to the electrical device 10 and remove the battery pack 12 from the electrical device 10.

[0054] Battery cells 40, 42, and 44 all have similar configurations. The following description will use battery cell 40 as an example. Battery cell 40 is a rechargeable secondary battery cell, such as a lithium-ion battery cell. Note that battery cell 40 may be other types of secondary battery cells, such as lithium metal battery cells, sodium-ion battery cells, or solid-state battery cells. As shown in Figure 7, battery cell 40 has a substantially cylindrical shape. Battery cell 40 is a so-called tablet-type battery cell. That is, as shown in Figure 8, battery cell 40 comprises a multilayer sheet 82 in which a separator sheet 74, a positive electrode sheet 76, a separator sheet 78, and a negative electrode sheet 80 are stacked in that order. The separator sheets 74 and 78 are made of, for example, polypropylene or polyethylene. The positive electrode sheet 76 is made of, for example, aluminum. The negative electrode sheet 80 is made of, for example, carbon. The multilayer sheet 82 is housed in a cylindrical can 84 (see Figure 7) in a state where it is wound cylindrically around a central axis extending in the short direction. A positive electrode current collector 86 is formed at one end of the positive electrode sheet 76 in the short direction, extending along the entire long side of the positive electrode sheet 76. The positive electrode current collector 86 is formed, for example, by making cuts at predetermined intervals along the long side of the positive electrode sheet 76 and folding the portion between each cut. A negative electrode current collector 88 is formed at the other end of the negative electrode sheet 80 in the short direction, extending along the entire long side of the negative electrode sheet 80. The negative electrode current collector 88 is formed, for example, by making cuts at predetermined intervals along the long side of the negative electrode sheet 80 and folding the portion between each cut. The positive electrode current collector 86 and the negative electrode current collector 88 are electrically connected to the positive electrode cell terminal 90 and the negative electrode cell terminal 92 (see Figure 7) of the battery cell 40, respectively. As shown in Figure 7, the positive electrode cell terminal 90 is located at one end of the can body 84 in the longitudinal direction. The negative electrode cell terminal 92 is located at the other end of the can body 84 in the longitudinal direction.

[0055] The shape of the battery cell 40 is, for example, that of an 18650 type. In this case, the diameter of the battery cell 40 is in the range of 17 [mm] - 20 [mm], for example, in the range of 17 [mm] - 19 [mm], for example, 18 [mm]. The height of the battery cell 40 is in the range of 64 [mm] - 67 [mm], for example, in the range of 65 [mm] - 66 [mm], for example, 65 [mm]. The weight of the battery cell 40 is in the range of 40 [g] - 50 [g], for example, in the range of 40 [g] - 45 [g], for example, 45 [g]. The DC internal resistance (DCIR) of the battery cell 40 is in the range of 2.5 [mΩ] - 20 [mΩ], for example, in the range of 5 [mΩ] - 20 [mΩ], for example, in the range of 10 [mΩ] - 15 [mΩ], for example, 15 [mΩ]. The rated voltage of the battery cell 40 is in the range of 3.24 [V] - 3.96 [V], for example, in the range of 3.42 [V] - 3.78 [V], for example, 3.6 [V]. The rated capacity of the battery cell 40 is in the range of 2.0 [Ah] - 4.0 [Ah], for example, in the range of 2.0 [Ah] - 3.5 [Ah], for example, 3.0 [Ah], or in the range of 2.0 [Ah] - 6.0 [Ah], for example, in the range of 3.0 [Ah] - 5.5 [Ah], for example, 5.0 [Ah]. The continuous discharge output of the battery cell 40 is in the range of 116 [W] - 268 [W], for example, in the range of 116 [W] - 256 [W], for example, in the range of 136 [W] - 197 [W], for example, 150 [W]. The continuous discharge output per unit mass of the battery cell 40 is within the range of 2.3 [W / g] - 6.7 [W / g], for example, within the range of 2.5 [W / g] - 5.9 [W / g], for example, within the range of 3.0 [W / g] - 4.3 [W / g], for example, 3.3 [W / g], or within the range of 2.0 [W / g] - 5.5 [W / g], for example, within the range of 2.5 [W / g] - 5.5 [W / g], for example, 4.0 [W / g].

[0056] Alternatively, the shape of the battery cell 40 may be, for example, type 21700. In this case, the diameter of the battery cell 40 is in the range of 21 [mm] - 23 [mm], for example, in the range of 21 [mm] - 22 [mm], for example, 21 [mm]. The height of the battery cell 40 is in the range of 70 [mm] - 72 [mm], for example, in the range of 70 [mm] - 71 [mm], for example, 70 [mm]. The weight of the battery cell 40 is in the range of 65 [g] - 75 [g], for example, in the range of 65 [g] - 70 [g], for example, 70 [g], or for example, 65 [g]. The DC internal resistance (DCIR) of the battery cell 40 is in the range of 2.5 [mΩ] - 15 [mΩ], for example, in the range of 5 [mΩ] - 15 [mΩ], for example, in the range of 10 [mΩ] - 15 [mΩ], for example, 15 [mΩ]. The rated voltage of the battery cell 40 is in the range of 3.24 [V] - 3.96 [V], for example, in the range of 3.42 [V] - 3.78 [V], for example, 3.6 [V]. The rated capacity of the battery cell 40 is in the range of 3.0 [Ah] - 6.0 [Ah], for example, in the range of 3.0 [Ah] - 5.5 [Ah], for example, 5.0 [Ah], or in the range of 2.0 [Ah] - 6.0 [Ah], for example, in the range of 3.0 [Ah] - 5.5 [Ah], for example, 5.0 [Ah]. The continuous discharge output of the battery cell 40 is in the range of 150 [W] - 392 [W], for example, in the range of 150 [W] - 365 [W], for example, in the range of 180 [W] - 273 [W], for example, 207 [W]. The continuous discharge output per unit mass of the battery cell 40 is within the range of 2.0 [W / g] to 6.0 [W / g], for example, within the range of 2.1 [W / g] to 5.6 [W / g], for example, within the range of 2.5 [W / g] to 3.9 [W / g], for example, 2.9 [W / g], or within the range of 2.0 [W / g] to 5.5 [W / g], for example, within the range of 2.5 [W / g] to 5.5 [W / g], for example, 3.5 [W / g].

[0057] The battery pack 12 is a slide-type battery pack, and in most cases, when the battery pack 12 is attached to the electrical device 10, the majority of the casing 52 is located outside the electrical device 10. For this reason, the shape and number of battery cells 40, 42, and 44 housed inside the casing 52 can be changed in various ways, and future changes in the shape of the battery cells 40, 42, and 44 can be flexibly accommodated by changing the shape of the casing 52.

[0058] As shown in Figure 5, the battery-side terminal 50 includes a positive power terminal 94 and a negative power terminal 96 for charging or discharging power between the electrical device 10 (see Figure 2) and the battery pack 12, and a signal communication terminal 98 for signal communication between the electrical device 10 and the battery pack 12. The positive power terminal 94 and the negative power terminal 96 are positioned to correspond to the positive power terminal 28 and the negative power terminal 30 (see Figure 2) of the electrical device 10. The signal communication terminal 98 is positioned to correspond to the signal communication terminal 32 (see Figure 2) of the electrical device 10. When the battery pack 12 is attached to the electrical device 10, the positive power terminal 94 and the negative power terminal 96 mechanically engage with and electrically connect to the positive power terminal 28 and the negative power terminal 30 of the electrical device 10 by clamping them from the left and right directions, respectively. When the battery pack 12 is attached to the electrical device 10, the signal communication terminal 98 mechanically engages with and electrically connects with the corresponding signal communication terminal 32 of the electrical device 10 by clamping it from the left and right directions.

[0059] As shown in Figure 9, the length from the front end to the rear end of the positive power terminal 94 is the same as the length from the front end to the rear end of the negative power terminal 96. The width from the right end to the left end of the positive power terminal 94 is the same as the width from the right end to the left end of the negative power terminal 96. The height from the mounting surface of the positive power terminal 94 (i.e., the top surface of the circuit board 48) to the top end of the positive power terminal 94 is the same as the height from the mounting surface of the negative power terminal 96 (i.e., the top surface of the circuit board 48) to the top end of the negative power terminal 96.

[0060] The plate thickness of the positive power terminal 94 (or negative power terminal 96) is in the range of 0.60 [mm] - 1.00 [mm], for example, in the range of 0.65 [mm] - 1.00 [mm], for example, in the range of 0.65 [mm] - 0.80 [mm], for example, 0.80 [mm], or in the range of 0.30 [mm] - 1.00 [mm], for example, in the range of 0.60 [mm] - 1.00 [mm], for example, in the range of 0.65 [mm] - 1.00 [mm], for example, 0.80 [mm]. The conductivity of the positive power terminal 94 (or negative power terminal 96) is in the range of 1 [%IACS] - 106 [%IACS], for example, in the range of 31 [%IACS] - 106 [%IACS], for example, 40 [%IACS]. The plate thickness of the signal communication terminal 98 is in the range of 0.30 [mm] - 1.00 [mm], for example, in the range of 0.30 [mm] - 0.64 [mm], for example, in the range of 0.30 [mm] - 0.59 [mm], for example, 0.45 [mm]. The conductivity of the signal communication terminal 98 is in the range of 1 [%IACS] - 106 [%IACS], for example, in the range of 1 [%IACS] - 30 [%IACS], for example, 25 [%IACS].

[0061] If the shape of the battery cell 40 is of the 18650 type, the length L1 from the front end to the rear end of the positive power terminal 94 (or negative power terminal 96) is in the range of 4.0 [mm] - 22.0 [mm], for example, in the range of 10.6 [mm] - 19.6 [mm], for example, 17.1 [mm]. The length L2 from the front end to the rear end of the casing 52 is in the range of 83.0 [mm] - 92.0 [mm], for example, in the range of 84.9 [mm] - 89.4 [mm], for example, 86.7 [mm], or in the range of 82.0 [mm] - 91.0 [mm], for example, in the range of 84.4 [mm] - 88.9 [mm], for example, 86.7 [mm]. The ratio of the length L1 from the front end to the rear end of the positive power terminal 94 (or negative power terminal 96) to the length L2 from the front end to the rear end of the casing 52 is within the range of 4.3 [%] - 26.5 [%], for example, within the range of 11.9 [%] - 23.1 [%], for example, 19.7 [%], or within the range of 4.4 [%] - 26.8 [%], for example, within the range of 11.9 [%] - 23.2 [%], for example, 19.7 [%]. The width W1 from the right end to the left end of the positive power terminal 94 (or negative power terminal 96) is within the range of 3.0 [mm] - 6.0 [mm], for example, within the range of 3.9 [mm] - 5.4 [mm], for example, 4.7 [mm]. The width W2 of the casing 52 from right end to left end is in the range of 61.0 [mm] - 67.0 [mm], for example, in the range of 62.5 [mm] - 65.5 [mm], for example, 64.0 [mm]. The ratio of the width W1 of the positive power terminal 94 (or negative power terminal 96) from right end to left end to the width W2 of the casing 52 from right end to left end is in the range of 4.5 [%] - 9.8 [%], for example, in the range of 6.0 [%] - 8.6 [%], for example, 7.3 [%]. The height H1 (see Figure 4) from the mounting surface of the positive power terminal 94 (or negative power terminal 96) (i.e., the upper surface of the circuit board 48) to the upper end of the positive power terminal 94 (or negative power terminal 96) is in the range of 7.0 [mm] to 14.0 [mm], for example, in the range of 8.9 [mm] to 12.4 [mm], for example, 10.7 [mm].The height H1 (see Figure 4) from the mounting surface of the signal communication terminal 98 (i.e., the top surface of the circuit board 48) to the upper end of the signal communication terminal 98 is in the range of 7.0 [mm] to 14.0 [mm], for example, in the range of 8.9 [mm] to 12.4 [mm], for example, 10.7 [mm].

[0062] When the shape of the battery cell 40 is of type 21700, the length L1 from the front end to the rear end of the positive power terminal 94 (or negative power terminal 96) is in the range of 4.0 [mm] - 22.0 [mm], for example, in the range of 10.6 [mm] - 19.6 [mm], for example, 17.1 [mm]. The length L2 from the front end to the rear end of the casing 52 is in the range of 87.0 [mm] - 96.0 [mm], for example, in the range of 89.1 [mm] - 93.6 [mm], for example, 91.1 [mm]. The ratio of the length L1 from the front end to the rear end of the positive power terminal 94 (or negative power terminal 96) to the length L2 from the front end to the rear end of the casing 52 is in the range of 4.2 [%] - 25.3 [%], for example, in the range of 11.3 [%] - 22.0 [%], for example, 18.8 [%]. The width W1 from the right end to the left end of the positive power terminal 94 (or negative power terminal 96) is in the range of 3.0 [mm] - 6.0 [mm], for example, in the range of 3.9 [mm] - 5.4 [mm], for example, 4.7 [mm]. The width W2 from the right end to the left end of the casing 52 is in the range of 70.0 [mm] - 78.0 [mm], for example, in the range of 72.1 [mm] - 76.1 [mm], for example, 74.1 [mm]. The ratio of the width W1 from the right end to the left end of the positive power terminal 94 (or negative power terminal 96) to the width W2 from the right end to the left end of the casing 52 is in the range of 3.8 [%] - 8.6 [%], for example, in the range of 5.1 [%] - 7.5 [%], for example, 6.3 [%]. The height H1 (see Figure 4) from the mounting surface of the positive power terminal 94 (or negative power terminal 96) (i.e., the top surface of the circuit board 48) to the upper end of the positive power terminal 94 (or negative power terminal 96) is in the range of 7.0 [mm] - 14.0 [mm], for example, in the range of 8.9 [mm] - 12.4 [mm], for example, 10.7 [mm]. The height H1 (see Figure 4) from the mounting surface of the signal communication terminal 98 (i.e., the top surface of the circuit board 48) to the upper end of the signal communication terminal 98 is in the range of 7.0 [mm] - 14.0 [mm], for example, in the range of 8.9 [mm] - 12.4 [mm], for example, 10.7 [mm].

[0063] The lead plate 49 is joined to the positive cell terminal 90 or negative cell terminal 92 (see Figure 7) of the battery cells 40, 42, and 44 by laser welding or spot welding. The thickness of the lead plate 49 is within the range of 0.10 [mm] - 1.00 [mm], for example, within the range of 0.31 [mm] - 1.00 [mm], for example, 0.5 [mm], or within the range of 0.10 [mm] - 0.19 [mm], within the range of 0.20 [mm] - 0.29 [mm], within the range of 0.30 [mm] - 0.39 [mm], within the range of 0.40 [mm] - 0.49 [mm], within the range of 0.50 [mm] - 0.59 [mm], within the range of 0.60 [mm] - 0.69 [mm], within the range of 0.70 [mm] - 0.79 [mm], within the range of 0.80 [mm] - 0.89 [mm], or within the range of 0.90 [mm] - 1.00 [mm]. The conductivity of the lead plate 49 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 31 [%IACS] to 106 [%IACS], for example, 40 [%IACS].

[0064] If the shape of the battery cells 40, 42, and 44 is of the 18650 type, the weight of the battery pack 12 is in the range of 180 [g] - 270 [g], for example, in the range of 200 [g] - 250 [g], for example, 210 [g], or in the range of 180 [g] - 270 [g], for example, in the range of 200 [g] - 240 [g], for example, 200 [g]. In this case, the rated voltage of the battery pack 12 is in the range of 9.72 [V] - 11.88 [V], for example, in the range of 10.26 [V] - 11.34 [V], for example, 10.8 [V]. The rated capacity of the battery pack 12 is in the range of 2.0 [Ah] - 4.0 [Ah], for example, in the range of 2.0 [Ah] - 3.5 [Ah], for example, 3.0 [Ah], or in the range of 2.0 [Ah] - 6.0 [Ah], for example, 4.0 [Ah] - 6.0 [Ah], for example, 5.0 [Ah]. The energy capacity of the battery pack 12 is in the range of 19.4 [Wh] - 47.5 [Wh], for example, in the range of 21.6 [Wh] - 37.8 [Wh], for example, 32.4 [Wh], or in the range of 19.44 [Wh] - 71.28 [Wh], for example, in the range of 41.04 [Wh] - 68.04 [Wh], for example, 54.0 [Wh]. The continuous discharge output of the battery pack 12 is in the range of 350 [W] - 800 [W], for example, in the range of 350 [W] - 770 [W], for example, in the range of 410 [W] - 590 [W], for example, 450 [W]. The continuous discharge output per unit mass of the battery pack 12 is in the range of 1.3 [W / g] - 4.4 [W / g], for example, in the range of 1.6 [W / g] - 3.8 [W / g], for example, in the range of 1.9 [W / g] - 2.8 [W / g], for example, 2.1 [W / g], or in the range of 1.5 [W / g] - 4.0 [W / g], for example, in the range of 1.8 [W / g] - 4.0 [W / g], for example, 2.5 [W / g].

[0065] If the shape of the battery cells 40, 42, and 44 is of type 21700, the weight of the battery pack 12 is in the range of 270 [g] - 380 [g], for example, in the range of 300 [g] - 350 [g], for example, 310 [g], or in the range of 270 [g] - 380 [g], for example, in the range of 300 [g] - 340 [g], for example, 300 [g]. In this case, the rated voltage of the battery pack 12 is in the range of 9.72 [V] - 11.88 [V], for example, in the range of 10.26 [V] - 11.34 [V], for example, 10.8 [V]. The rated capacity of the battery pack 12 is in the range of 3.0 [Ah] - 6.0 [Ah], for example, in the range of 3.0 [Ah] - 5.5 [Ah], for example, 5.0 [Ah], or in the range of 2.0 [Ah] - 6.0 [Ah], for example, in the range of 4.0 [Ah] - 6.0 [Ah], for example, 5.0 [Ah]. The energy capacity of the battery pack 12 is in the range of 29.2 [Wh] - 71.3 [Wh], for example, in the range of 32.4 [Wh] - 59.4 [Wh], for example, 54.0 [Wh], or in the range of 19.44 [Wh] - 71.28 [Wh], for example, in the range of 41.04 [Wh] - 68.04 [Wh], for example, 54.0 [Wh]. The continuous discharge output of the battery pack 12 is in the range of 450 [W] - 1180 [W], for example, in the range of 450 [W] - 1090 [W], for example, in the range of 540 [W] - 820 [W], for example, 620 [W]. The continuous discharge output per unit mass of the battery pack 12 is in the range of 1.2 [W / g] - 4.4 [W / g], for example, in the range of 1.4 [W / g] - 3.8 [W / g], for example, in the range of 1.7 [W / g] - 2.6 [W / g], for example, 2.0 [W / g], or in the range of 1.5 [W / g] - 4.0 [W / g], for example, in the range of 1.8 [W / g] - 4.0 [W / g], for example, 2.0 [W / g].

[0066] Figure 45 shows an example of the circuit configuration of the battery pack 12 and the electrical device 10. The battery pack 12 further includes a fuse link 330, a cell temperature detection circuit 332, a power supply circuit 334, a current detection circuit 336, an AFE (Analog Front End) 338, an MCU (Micro Controller Unit) 340, a voltage detection circuit 342, a protection FET (Field Effect Transistor) circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. The power supply circuit 334, current detection circuit 336, AFE 338, MCU 340, voltage detection circuit 342, protection FET circuit 344, FET temperature detection circuit 346, charger detection circuit 348, and input / output control circuit 350 are provided on a circuit board 48.

[0067] The fuse link 330 is provided on the lead plate 49 (see Figure 5) that connects the positive terminal 90 (see Figure 7) of the battery cell 40, which is the most positive of the battery cells 40 connected in series, to the circuit board 48. The fuse link 330 protects the battery cells 40, 42, 44, the circuit board 48, etc., by melting due to the heat generated when an overcurrent flows. Alternatively, the fuse link 330 may be provided on the lead plate 49 (see Figure 5) that connects the negative terminal 92 (see Figure 7) of the battery cell 44, which is the most negative of the battery cells 44 connected in series, to the circuit board 48.

[0068] The cell temperature detection circuit 332 detects the temperature near the battery cells 40, 42, and 44. The cell temperature detection circuit 332 outputs a signal indicating the detected temperature to the MCU 340.

[0069] The power supply circuit 334 adjusts the power supplied from the battery cells 40, 42, and 44 to generate the power supply voltage Vcc used by the circuit board 48.

[0070] The current detection circuit 336 detects the current flowing through the battery cells 40, 42, and 44 and outputs it to the AFE 338.

[0071] The AFE338 includes an amplifier, A / D converter, filter, etc. The AFE338 detects the inter-cell voltages of battery cells 40, 42, and 44 and outputs them to the MCU340. The AFE338 also outputs the current value detected by the current detection circuit 336 to the MCU340.

[0072] The MCU340 includes a CPU, RAM, ROM, etc. The MCU340 controls the operation of each component of the battery pack 12 by having the CPU execute various processes according to the program stored in the ROM.

[0073] The voltage detection circuit 342 detects the voltage between the positive power terminal 94 and the negative power terminal 96 and outputs it to the MCU 340.

[0074] The protective FET circuit 344 is provided between the negative power terminal 96 and the battery cells 40, 42, and 44. The protective FET circuit 344 comprises one or more FETs connected in parallel with each other. The conduction / non-conductivity of the protective FET circuit 344 is controlled by the MCU 340. The protective FET circuit 344 may also be provided between the positive power terminal 94 and the battery cells 40, 42, and 44.

[0075] The FET temperature detection circuit 346 detects the temperature near the protective FET circuit 344. The FET temperature detection circuit 346 outputs a signal indicating the detected temperature to the MCU 340.

[0076] One of the signal communication terminals 98 is connected to the MCU 340 via the charger detection circuit 348. The charger detection circuit 348 determines whether the electrical device 10 to which the battery pack 12 is attached is a charger and outputs a signal indicating the determination result to the MCU 340.

[0077] Another of the signal communication terminals 98 is directly connected to the MCU 340.

[0078] Another signal communication terminal 98 is connected to the MCU 340 via the input / output control circuit 350. In the example shown in Figure 45, this signal communication terminal 98 is connected to the signal communication terminal 32 of the electrical device 10. When the battery pack 12 receives a signal from the electrical device 10, the input / output control circuit 350 receives the signal from the signal communication terminal 98 and outputs it to the MCU 340. Also, when the battery pack 12 transmits a signal to the electrical device 10, the input / output control circuit 350 receives the signal from the MCU 340 and outputs it to the signal communication terminal 98.

[0079] The electrical device 10 includes a power supply circuit 352, an MCU 354, an LED (Light Emitting Diode) 356, a trigger switch 358, a motor control circuit 360, a motor drive circuit 362, an electric motor 364, a protection FET circuit 366, and an FET control circuit 368.

[0080] The power supply circuit 352 adjusts the power supplied from the battery pack 12 to generate the power supply voltage Vdd used by the electrical equipment 10.

[0081] The MCU 354 includes a CPU, RAM, ROM, etc. The MCU 354 controls the operation of each component of the electrical device 10 by having the CPU execute various processes according to the program stored in the ROM. The MCU 354 is connected to a signal communication terminal 32. When the electrical device 10 sends a signal to the battery pack 12, the signal is output from the MCU 354 to the signal communication terminal 32. When the electrical device 10 receives a signal from the battery pack 12, the signal is input to the MCU 354 from the signal communication terminal 32.

[0082] The LED 356 illuminates in a manner corresponding to the state of the electrical device 10, thereby informing the user of the state of the electrical device 10. The operation of the LED 356 is controlled by the MCU 354.

[0083] The trigger switch 358 detects the user's operation in response to the trigger of the electrical device 10 and outputs it to the MCU 354.

[0084] The motor control circuit 360 controls the operation of the electric motor 364 via the motor drive circuit 362. The motor drive circuit 362 is, for example, a three-phase inverter circuit. Power is supplied to the motor drive circuit 362 from the battery pack 12 via the positive power terminal 28 and the negative power terminal 30. The operation of the motor control circuit 360 is controlled by the MCU 354.

[0085] The protective FET circuit 366 is located between the positive power terminal 28 and the motor drive circuit 362. The protective FET circuit 366 comprises one or more FETs connected in parallel with each other. The conduction / non-conductivity of the protective FET circuit 366 is controlled by the FET control circuit 368. The FET control circuit 368 switches the conduction / non-conductivity of the protective FET circuit 366 based on signals from the MCU 354 and the state of the electrical equipment 10.

[0086] The total number of pins in the MCU 340 of the battery pack 12 is in the range of 33-100, for example, in the range of 33-60, for example, 48. The ROM capacity of the MCU 340 of the battery pack 12 is in the range of 64 [kByte]-1024 [kByte], for example, in the range of 64 [kByte]-256 [kByte], for example, 128 [kByte]. The RAM capacity of the MCU 340 of the battery pack 12 is in the range of 5 [kByte]-32 [kByte], for example, in the range of 6 [kByte]-16 [kByte], for example, 7 [kByte]. The CPU clock frequency of the MCU 340 of the battery pack 12 is within the range of 19.3 [MHz] to 128.0 [MHz], for example, within the range of 25.6 [MHz] to 48.0 [MHz], for example, 32.0 [MHz]. The number of parallel FETs in the protection FET circuit 344 of the battery pack 12 is within the range of 0 to 4, for example, within the range of 1 to 4, for example, within the range of 2 to 3, for example, 2. The ON resistance of each FET in the protection FET circuit 344 of the battery pack 12 is within the range of 0.10 [mΩ] to 0.59 [mΩ], for example, within the range of 0.30 [mΩ] to 0.50 [mΩ], for example, 0.45 [mΩ]. Note that the ON resistance referred to here is the maximum value of the ON resistance when a voltage of 10 [V] is applied between the gate and source in an environment of 25 [℃] ± 2 [℃]. The total ON resistance of the protection FET circuit 344 of the battery pack 12 is in the range of 0.05 [mΩ] to 0.29 [mΩ], for example, in the range of 0.15 [mΩ] to 0.25 [mΩ], for example, 0.23 [mΩ].

[0087] (Configuration of Battery Pack 14) Battery pack 14 has a configuration that is almost identical to that of battery pack 12. The following mainly describes the differences between battery pack 14 and battery pack 12.

[0088] As shown in Figure 5, the battery pack 14 is equipped with battery cells 100, 102, and 104 instead of battery cells 40, 42, and 44. The battery cells 100, 102, and 104 are arranged in a row, one in the vertical direction and three in the horizontal direction, with their longitudinal direction aligned with the front-to-back direction. The battery cells 100, 102, and 104 are electrically connected in series via lead plates 49.

[0089] Battery cells 100, 102, and 104 all have similar configurations. The following description will use battery cell 100 as an example. Battery cell 100 is a rechargeable secondary battery cell, for example, a lithium-ion battery cell. Note that battery cell 100 may be other types of secondary battery cells, such as lithium metal battery cells, sodium-ion battery cells, or solid-state battery cells. As shown in Figure 7, battery cell 100 has a substantially cylindrical shape. Battery cell 100 is a so-called tab-type battery cell. That is, as shown in Figure 10, battery cell 100 comprises a multilayer sheet 114 in which a separator sheet 106, a positive electrode sheet 108, a separator sheet 110, and a negative electrode sheet 112 are stacked in order. Separator sheets 106 and 110 are made of, for example, polypropylene or polyethylene. The positive electrode sheet 108 is made of, for example, aluminum. The negative electrode sheet 112 is made of, for example, carbon. The multilayer sheet 114 is wound in a cylindrical shape around a central axis extending in the short direction and is housed in a cylindrical can 116 (see Figure 7). A positive electrode current collector tab 118 is attached to one longitudinal end of the positive electrode sheet 108. The positive electrode current collector tab 118 extends along the short direction of the positive electrode sheet 108 and protrudes outward beyond the one short end of the positive electrode sheet 108. The positive electrode current collector tab 118 is made of, for example, aluminum. A negative electrode current collector tab 120 is attached to the other longitudinal end of the negative electrode sheet 112. The negative electrode current collector tab 120 extends along the short direction of the negative electrode sheet 112 and protrudes outward beyond the other short end of the negative electrode sheet 112. The negative electrode current collector tab 120 is made of, for example, nickel-plated copper. The positive electrode current collector tab 118 and the negative electrode current collector tab 120 are connected to the positive electrode cell terminal 122 and the negative electrode cell terminal 124 (see Figure 7) of the battery cell 100, respectively. In the example shown in Figure 10, one positive electrode current collector tab 118 and one negative electrode current collector tab 120 are shown, but two or more positive electrode current collector tabs 118 and negative electrode current collector tabs 120 may be provided. As shown in Figure 7, the positive electrode cell terminal 122 is located at one end of the can body 116 in the longitudinal direction. The negative electrode cell terminal 124 is located at the other end of the can body 116 in the longitudinal direction.

[0090] The shape of the battery cell 100 is, for example, that of an 18650 type. In this case, the diameter of the battery cell 100 is in the range of 17 [mm] - 20 [mm], for example, in the range of 17 [mm] - 19 [mm], for example, 18 [mm]. The height of the battery cell 100 is in the range of 64 [mm] - 67 [mm], for example, in the range of 65 [mm] - 66 [mm], for example, 65 [mm]. The weight of the battery cell 100 is in the range of 40 [g] - 50 [g], for example, in the range of 40 [g] - 45 [g], for example, 45 [g], or in the range of 40 [g] - 50 [g], for example, in the range of 45 [g] - 50 [g], for example, 50 [g]. The DC internal resistance (DCIR) of the battery cell 100 is in the range of 21 [mΩ] - 100 [mΩ], for example, in the range of 21 [mΩ] - 50 [mΩ], for example, in the range of 30 [mΩ] - 40 [mΩ], for example, 35 [mΩ]. The rated voltage of the battery cell 100 is in the range of 3.24 [V] - 3.96 [V], for example, in the range of 3.42 [V] - 3.78 [V], for example, 3.6 [V]. The rated capacity of the battery cell 100 is in the range of 2.0 [Ah] - 4.0 [Ah], for example, in the range of 2.0 [Ah] - 3.5 [Ah], for example, 3.0 [Ah], or in the range of 2.0 [Ah] - 6.0 [Ah], for example, in the range of 3.0 [Ah] - 5.5 [Ah], for example, 5.0 [Ah]. The continuous discharge output of the battery cell 100 is in the range of 30 [W] - 114 [W], for example, in the range of 35 [W] - 114 [W], for example, in the range of 58 [W] - 93 [W], for example, 78 [W]. The continuous discharge output per unit mass of the battery cell 100 is in the range of 0.6 [W / g] - 2.9 [W / g], for example, in the range of 0.6 [W / g] - 2.5 [W / g], for example, in the range of 1.2 [W / g] - 2.0 [W / g], for example, 1.7 [W / g], or in the range of 1.0 [W / g] - 2.5 [W / g], for example, in the range of 1.5 [W / g] - 2.2 [W / g], for example, 2.0 [W / g].

[0091] If the shape of battery cells 100, 102, and 104 is of the 18650 type, the weight of the battery pack 14 is in the range of 180 [g] - 270 [g], for example, in the range of 200 [g] - 250 [g], for example, 210 [g]. In this case, the rated voltage of the battery pack 14 is in the range of 9.72 [V] - 11.88 [V], for example, in the range of 10.26 [V] - 11.34 [V], for example, 10.8 [V]. The rated capacity of the battery pack 14 is in the range of 2.0 [Ah] - 4.0 [Ah], for example, in the range of 2.0 [Ah] - 3.5 [Ah], for example, 3.0 [Ah], or in the range of 2.0 [Ah] - 6.0 [Ah], for example, in the range of 4.0 [Ah] - 6.0 [Ah], for example, 5.0 [Ah]. The energy capacity of the battery pack 14 is in the range of 19.4 [Wh] - 47.5 [Wh], for example, in the range of 21.6 [Wh] - 37.8 [Wh], for example, 32.4 [Wh]. The continuous discharge output of the battery pack 14 is in the range of 90 [W] - 340 [W], for example, in the range of 110 [W] - 340 [W], for example, in the range of 170 [W] - 280 [W], for example, 230 [W]. The continuous discharge output per unit mass of the battery pack 14 is in the range of 0.3 [W / g] - 1.9 [W / g], for example, in the range of 0.4 [W / g] - 1.6 [W / g], for example, in the range of 0.8 [W / g] - 1.3 [W / g], for example, 1.0 [W / g].

[0092] Alternatively, the shape of the battery cell 100 may be, for example, type 21700. In this case, the diameter of the battery cell 100 is in the range of 21 [mm] - 23 [mm], for example, in the range of 21 [mm] - 22 [mm], for example, 21 [mm]. The height of the battery cell 100 is in the range of 70 [mm] - 72 [mm], for example, in the range of 70 [mm] - 71 [mm], for example, 70 [mm]. The weight of the battery cell 100 is in the range of 65 [g] - 75 [g], for example, in the range of 65 [g] - 70 [g], for example, 70 [g], or in the range of 65 [g] - 75 [g], for example, in the range of 70 [g] - 75 [g], for example, 70 [g]. The DC internal resistance (DCIR) of the battery cell 100 is in the range of 16 [mΩ] - 100 [mΩ], for example, in the range of 16 [mΩ] - 50 [mΩ], for example, in the range of 20 [mΩ] - 40 [mΩ], for example, 25 [mΩ]. The rated voltage of the battery cell 100 is in the range of 3.24 [V] - 3.96 [V], for example, in the range of 3.42 [V] - 3.78 [V], for example, 3.6 [V]. The rated capacity of the battery cell 100 is in the range of 3.0 [Ah] - 6.0 [Ah], for example, in the range of 3.0 [Ah] - 5.5 [Ah], for example, 5.0 [Ah], or in the range of 2.0 [Ah] - 6.0 [Ah], for example, in the range of 3.0 [Ah] - 5.5 [Ah], for example, 5.0 [Ah]. The continuous discharge output of the battery cell 100 is in the range of 30 [W] - 148 [W], for example, in the range of 35 [W] - 148 [W], for example, in the range of 64 [W] - 122 [W], for example, 98 [W]. The continuous discharge output per unit mass of the battery cell 100 is in the range of 0.4 [W / g] - 2.3 [W / g], for example, in the range of 0.4 [W / g] - 2.1 [W / g], for example, in the range of 0.9 [W / g] - 1.7 [W / g], for example, 1.3 [W / g], or in the range of 1.0 [W / g] - 2.5 [W / g], for example, in the range of 1.5 [W / g] - 2.2 [W / g], for example, 2.0 [W / g].

[0093] If the shape of battery cells 100, 102, and 104 is of type 21700, the weight of the battery pack 14 is in the range of 270 [g] - 380 [g], for example, in the range of 300 [g] - 350 [g], for example, 310 [g]. In this case, the rated voltage of the battery pack 14 is in the range of 9.72 [V] - 11.88 [V], for example, in the range of 10.26 [V] - 11.34 [V], for example, 10.8 [V]. The rated capacity of the battery pack 14 is in the range of 3.0 [Ah] - 6.0 [Ah], for example, in the range of 3.0 [Ah] - 5.5 [Ah], for example, 5.0 [Ah], or in the range of 2.0 [Ah] - 6.0 [Ah], for example, in the range of 4.0 [Ah] - 6.0 [Ah], for example, 5.0 [Ah]. The energy capacity of the battery pack 14 is in the range of 29.2 [Wh] - 71.3 [Wh], for example, in the range of 32.4 [Wh] - 59.4 [Wh], for example, 54.0 [Wh], or in the range of 19.44 [Wh] - 71.28 [Wh], for example, in the range of 41.04 [Wh] - 68.04 [Wh], for example, 54.0 [Wh]. The continuous discharge output of the battery pack 14 is in the range of 90 [W] - 440 [W], for example, in the range of 110 [W] - 440 [W], for example, in the range of 190 [W] - 370 [W], for example, 290 [W]. The continuous discharge output per unit mass of the battery pack 14 is within the range of 0.2 [W / g] - 1.6 [W / g], for example, within the range of 0.2 [W / g] - 1.4 [W / g], for example, within the range of 0.6 [W / g] - 1.1 [W / g], for example, 0.9 [W / g], or within the range of 0.75 [W / g] - 1.8 [W / g], for example, within the range of 1.0 [W / g] - 1.8 [W / g], for example, 1.7 [W / g].

[0094] In the battery pack 14, the height H1 (see Figure 4) from the mounting surface of the positive power terminal 94 (or negative power terminal 96) (i.e., the upper surface of the circuit board 48) to the upper end of the positive power terminal 94 (or negative power terminal 96) is in the range of 7.0 [mm] to 14.0 [mm], for example, in the range of 8.9 [mm] to 12.4 [mm], for example, 10.7 [mm]. In the battery pack 14, the plate thickness of the positive power terminal 94 (or negative power terminal 96) is in the range of 0.30 [mm] - 0.64 [mm], for example, in the range of 0.30 [mm] - 0.59 [mm], for example, in the range of 0.40 [mm] - 0.55 [mm], for example, 0.50 [mm], or in the range of 0.30 [mm] - 1.00 [mm], for example, in the range of 0.30 [mm] - 0.64 [mm], for example, in the range of 0.30 [mm] - 0.59 [mm], for example, 0.45 [mm]. In the battery pack 14, the conductivity of the positive power terminal 94 (or negative power terminal 96) is in the range of 1 [%IACS] - 106 [%IACS], for example, in the range of 1 [%IACS] - 30 [%IACS], for example, 25 [%IACS].

[0095] In the battery pack 14, the lead plate 49 is joined to the positive cell terminal 122 or negative cell terminal 124 (see Figure 7) of the battery cells 100, 102, and 104 by spot welding. In the battery pack 14, the thickness of the lead plate 49 is within the range of 0.10 [mm] - 1.00 [mm], for example, within the range of 0.10 [mm] - 0.30 [mm], for example, 0.2 [mm], or within the range of 0.10 [mm] - 0.19 [mm], within the range of 0.20 [mm] - 0.29 [mm], within the range of 0.30 [mm] - 0.39 [mm], within the range of 0.40 [mm] - 0.49 [mm], within the range of 0.50 [mm] - 0.59 [mm], within the range of 0.60 [mm] - 0.69 [mm], within the range of 0.70 [mm] - 0.79 [mm], within the range of 0.80 [mm] - 0.89 [mm], or within the range of 0.90 [mm] - 1.00 [mm]. In the battery pack 14, the conductivity of the lead plate 49 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 1 [%IACS] to 30 [%IACS], for example, 25 [%IACS].

[0096] As shown in Figure 45, the battery pack 14, like the battery pack 12, further includes a fuse link 330, a cell temperature detection circuit 332, a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. Note that the battery pack 14 does not necessarily have a fuse link 330. Also, the battery pack 14 does not necessarily have a circuit board 48. Therefore, the battery pack 14 does not necessarily have a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. In this case, the cell temperature detection circuit 332 and the positive cell terminals 122 and / or negative cell terminals 124 (see Figure 7) of each battery cell 100, 102, and 104 may be directly connected to the signal communication terminal 98.

[0097] The total number of pins of the MCU340 in the battery pack 14 is in the range of 6-32, for example, in the range of 16-32, for example, 32. The ROM capacity of the MCU340 in the battery pack 14 is in the range of 8 [kByte]-63 [kByte], for example, in the range of 16 [kByte]-32 [kByte], for example, 32 [kByte]. The RAM capacity of the MCU340 in the battery pack 14 is in the range of 1 [kByte]-4 [kByte], for example, in the range of 2 [kByte]-4 [kByte], for example, 4 [kByte]. The CPU clock frequency of the MCU340 in the battery pack 14 is in the range of 4.8 [MHz]-19.2 [MHz], for example, in the range of 14.4 [MHz]-17.6 [MHz], for example, 16.0 [MHz]. The number of FETs in parallel in the protection FET circuit 344 of the battery pack 14 is in the range of 0-3, for example, in the range of 0-2, for example, in the range of 1-2, for example, 1. The ON resistance of each FET in the protection FET circuit 344 of the battery pack 14 is in the range of 0.60 [mΩ]-5.00 [mΩ], for example, in the range of 0.60 [mΩ]-1.00 [mΩ], for example, 0.65 [mΩ]. The total ON resistance of the protection FET circuit 344 of the battery pack 14 is in the range of 0.30 [mΩ]-5.00 [mΩ], for example, in the range of 0.30 [mΩ]-0.50 [mΩ], for example, 0.33 [mΩ].

[0098] (Comparison of battery pack 12 and battery pack 14) The tablet-type battery cells 40, 42, and 44 used in battery pack 12 generate less heat in the positive electrode current collector 86 and negative electrode current collector 88 and have lower internal resistance compared to the tab-type battery cells 100, 102, and 104 used in battery pack 14. Therefore, the tablet-type battery cells 40, 42, and 44 can achieve higher output than the tab-type battery cells 100, 102, and 104. Also, battery pack 12 can achieve higher output than battery pack 14.

[0099] The battery pack 12, which uses tablet-type battery cells 40, 42, and 44, can achieve higher output without significantly changing its shape or weight compared to the battery pack 14, which uses tab-type battery cells 100, 102, and 104. For example, the battery pack 12 can have a higher output than the battery pack 14 while keeping the weight ratio of the battery pack 12 to the weight of the battery pack 14 within the range of 0.9 to 1.1.

[0100] When the output of the battery pack 12 is increased compared to the battery pack 14, the current flowing through the current path increases, and heat generation also increases. Therefore, in the battery pack 12, the conductivity of the positive power terminal 94, the negative power terminal 96, and the lead plate 49 is increased compared to the battery pack 14, thereby reducing the resistance of the current path and suppressing heat generation. In addition, in the battery pack 12, the plate thickness of the positive power terminal 94, the negative power terminal 96, and the lead plate 49 is increased compared to the battery pack 14, thereby reducing the resistance of the current path and suppressing heat generation. In particular, when the plate thickness of the positive power terminal 94 and the negative power terminal 96 is increased, in addition to reducing resistance by increasing the cross-sectional area of ​​the conductive path within the terminal, resistance can also be reduced by increasing the soldering area of ​​the connection part with the circuit board 48, and by increasing the contact pressure with the positive power terminal 28 and the negative power terminal 30 of the electrical device 10. Furthermore, if the thickness of the positive power terminal 94 and the negative power terminal 96 is increased, the contact pressure on the positive power terminal 28 and the negative power terminal 30 of the electrical device 10 may become too large, which could reduce the operability when attaching and detaching the battery pack 12 to the electrical device 10. For this reason, the battery pack 12 has a higher height for the positive power terminal 94 and the negative power terminal 96 compared to the battery pack 14, thereby suppressing excessive contact pressure on the positive power terminal 28 and the negative power terminal 30 of the electrical device 10. In addition, generally, it becomes difficult to ensure quality reliability with spot welding when the thickness of the lead plate 49 is increased. In contrast, even if the thickness of the lead plate 49 is increased, it is easier to ensure quality reliability with laser welding. For this reason, in the battery pack 12, it is preferable to join the lead plate 49 to the positive cell terminal 90 or negative cell terminal 92 (see Figure 7) of the battery cells 40, 42, and 44 by laser welding.

[0101] When the output of the battery pack 12 is increased compared to the battery pack 14, it is expected that the vibration and weight of the electrical equipment 10 that can use the battery pack 12 will increase. For this reason, the battery pack 12 can improve the strength of the positive power terminal 94, negative power terminal 96, and lead plate 49 against vibration and drops of the electrical equipment 10 by increasing the thickness of the positive power terminal 94, negative power terminal 96, and lead plate 49 compared to the battery pack 14. In addition, the strength of the positive power terminal 94 and negative power terminal 96 against vibration and drops of the electrical equipment 10 can be improved by increasing the height of the positive power terminal 94 and negative power terminal 96.

[0102] When increasing the output power of battery pack 12 compared to battery pack 14, it is necessary to set a higher cutoff current value for overcurrent protection. However, if overcurrent protection is performed using circuit elements, problems in terms of heat generation and durability are likely to occur. Therefore, battery pack 12 uses a fuse link 330, which is a mechanical component, for overcurrent protection. Note that battery pack 14 may or may not use a fuse link 330.

[0103] The battery pack 12, which uses tablet-type battery cells 40, 42, and 44, is capable of rapid charging and heavy-load discharge compared to the battery pack 14, which uses tab-type battery cells 100, 102, and 104. For this reason, the battery pack 12 uses an MCU 340 to precisely control charging and discharging. In this case, in order to control charging and discharging more precisely, it is preferable that the total number of pins of the MCU 340 be large, the ROM capacity of the MCU 340 be large, the RAM capacity of the MCU 340 be large, and the CPU clock frequency of the MCU 340 be high. Note that the battery pack 14 may or may not use the MCU 340.

[0104] When the battery pack 12 has a higher output than the battery pack 14, a large current flows through the battery pack 12. In this case, it is necessary to reduce the current flowing through each FET of the protection FET circuit 344, so it is preferable for the battery pack 12 to have a large number of FETs in parallel in the protection FET circuit 344. Also, in the battery pack 12, in order to reduce the heat generated in the protection FET circuit 344, it is preferable for the ON resistance of each FET in the protection FET circuit 344 to be small, and for the total ON resistance of the protection FET circuit 344 to be small. The same applies to the protection FET circuit 366 on the electrical equipment 10 side when using the battery pack 12.

[0105] (Configuration of Battery Pack 16) As shown in Figure 11, the battery pack 16 comprises battery cells 126, 128, 130, 132, 134, 136 (see Figure 12), a cell holder 138, a circuit board 140, a lead plate 141, battery-side terminals 142, and a casing 144. As shown in Figure 12, the battery cells 126, 128, 130, 132, 134, 136 are arranged in two rows vertically and three rows horizontally, with their longitudinal direction aligned with the front-to-back direction. Battery cells 126 and 128 are electrically connected in parallel via the lead plate 141 to form a battery cell pair 146. Battery cells 130 and 132 are electrically connected in parallel via the lead plate 141 to form a battery cell pair 148. Battery cells 134 and 136 are electrically connected in parallel via the lead plate 141 to form a battery cell pair 150. The battery cell pairs 146, 148, and 150 are electrically connected in series via lead plates 141. The cell holder 138 holds the battery cells 126, 128, 130, 132, 134, and 136. The circuit board 140 is held by the cell holder 138 above it and is electrically connected to the battery cells 126, 128, 130, 132, 134, and 136 via lead plates 141. The battery-side terminals 142 are provided on the circuit board 140. As shown in Figure 11, the casing 144 houses the battery cells 126, 128, 130, 132, 134, and 136, the cell holder 138, the circuit board 140, the lead plates 141, and the battery-side terminals 142.

[0106] As shown in Figure 13, the casing 144 comprises a lower casing 152 and an upper casing 154. The upper casing 154 has terminal openings 58 and battery-side rails 60, similar to the battery packs 12 and 14.

[0107] A hook 156 is attached to the upper casing 154. The hook 156 has an engaging portion 158 and an operating portion 160. As shown in Figure 11, the hook 156 is biased upward by a compression spring 162. When the battery pack 16 is attached to the electrical device 10, the engaging portion 158 of the hook 156 fits into the engaging groove 26 (see Figure 3) of the electrical device 10, thereby fixing the battery pack 16 to the electrical device 10. From this state, when the user pushes down the operating portion 160 of the hook 156, the engaging portion 158 disengages from the engaging groove 26. In this state, the user can slide the battery pack 16 forward relative to the electrical device 10 and remove the battery pack 16 from the electrical device 10.

[0108] Battery cells 126, 128, 130, 132, 134, and 136 all have the same configuration as battery cell 40 of battery pack 12. That is, battery cells 126, 128, 130, 132, 134, and 136 are tablet-type battery cells.

[0109] As shown in Figure 12, the battery-side terminal 142 includes a positive power terminal 164 and a negative power terminal 166 for charging or discharging power between the electrical device 10 and the battery pack 16, and a signal communication terminal 168 for signal communication between the electrical device 10 and the battery pack 16. The positive power terminal 164 and the negative power terminal 166 are positioned to correspond to the positive power terminal 28 and the negative power terminal 30 (see Figure 3) of the electrical device 10. The signal communication terminal 168 is positioned to correspond to the signal communication terminal 32 of the electrical device 10. When the battery pack 16 is attached to the electrical device 10, the positive power terminal 164 and the negative power terminal 166 mechanically engage with and electrically connect to the positive power terminal 28 and the negative power terminal 30 of the electrical device 10 by clamping them from the left and right directions, respectively. When the battery pack 16 is attached to the electrical device 10, the signal communication terminal 168 mechanically engages with and electrically connects with the corresponding signal communication terminal 32 of the electrical device 10 by clamping it from the left and right directions.

[0110] As shown in Figure 14, the length from the front end to the rear end of the positive power terminal 164 is the same as the length from the front end to the rear end of the negative power terminal 166. The width from the right end to the left end of the positive power terminal 164 is the same as the width from the right end to the left end of the negative power terminal 166. The height from the mounting surface of the positive power terminal 164 (i.e., the top surface of the circuit board 140) to the top end of the positive power terminal 164 is the same as the height from the mounting surface of the negative power terminal 166 (i.e., the top surface of the circuit board 140) to the top end of the negative power terminal 166.

[0111] The plate thickness of the positive power terminal 164 (or negative power terminal 166) is in the range of 0.60 [mm] - 1.00 [mm], for example, in the range of 0.65 [mm] - 1.00 [mm], for example, in the range of 0.65 [mm] - 0.80 [mm], for example, 0.80 [mm], or in the range of 0.30 [mm] - 1.00 [mm], for example, in the range of 0.60 [mm] - 1.00 [mm], for example, in the range of 0.65 [mm] - 1.00 [mm], for example, 0.80 [mm]. The conductivity of the positive power terminal 164 (or negative power terminal 166) is in the range of 1 [%IACS] - 106 [%IACS], for example, in the range of 31 [%IACS] - 106 [%IACS], for example, 40 [%IACS]. The plate thickness of the signal communication terminal 168 is in the range of 0.30 [mm] - 1.00 [mm], for example, in the range of 0.30 [mm] - 0.64 [mm], for example, in the range of 0.30 [mm] - 0.59 [mm], for example, 0.45 [mm]. The conductivity of the signal communication terminal 168 is in the range of 1 [%IACS] - 106 [%IACS], for example, in the range of 1 [%IACS] - 30 [%IACS], for example, 25 [%IACS].

[0112] If the shape of the battery cells 126, 128, 130, 132, 134, and 136 is of the 18650 type, the length L3 from the front end to the rear end of the positive power terminal 164 (or negative power terminal 166) is in the range of 4.0 [mm] to 22.0 [mm], for example, in the range of 10.6 [mm] to 19.6 [mm], for example, 17.1 [mm]. The length L4 from the front end to the rear end of the casing 144 is in the range of 83.0 [mm] to 92.0 [mm], for example, in the range of 84.9 [mm] to 89.4 [mm], for example, 86.7 [mm], or in the range of 82.0 [mm] to 91.0 [mm], for example, in the range of 84.4 [mm] to 88.9 [mm], for example, 86.7 [mm]. The ratio of the length L3 of the positive power terminal 164 (or negative power terminal 166) from its front end to its rear end to the length L4 of the casing 144 from its front end to its rear end is within the range of 4.3 [%] - 26.5 [%], for example, within the range of 11.9 [%] - 23.1 [%], for example, 19.7 [%], or within the range of 4.4 [%] - 26.8 [%], for example, within the range of 11.9 [%] - 23.2 [%], for example, 19.7 [%]. The width W3 of the positive power terminal 164 (or negative power terminal 166) from its right end to its left end is within the range of 3.0 [mm] - 6.0 [mm], for example, within the range of 3.9 [mm] - 5.4 [mm], for example, 4.7 [mm]. The width W4 of the casing 144 from right end to left end is in the range of 61.0 [mm] - 67.0 [mm], for example, in the range of 62.5 [mm] - 65.5 [mm], for example, 64.0 [mm]. The ratio of the width W3 of the positive power terminal 164 (or negative power terminal 166) from right end to left end to the width W4 of the casing 144 from right end to left end is in the range of 4.5 [%] - 9.8 [%], for example, in the range of 6.0 [%] - 8.6 [%], for example, 7.3 [%]. The height H2 (see Figure 11) from the mounting surface of the positive power terminal 164 (or negative power terminal 166) (i.e., the upper surface of the circuit board 140) to the upper end of the positive power terminal 164 (or negative power terminal 166) is in the range of 7.0 [mm] to 14.0 [mm], for example, in the range of 8.9 [mm] to 12.4 [mm], for example, 10.7 [mm].The height H2 (see Figure 11) from the mounting surface of the signal communication terminal 168 (i.e., the top surface of the circuit board 140) to the upper end of the signal communication terminal 168 is in the range of 7.0 [mm] to 14.0 [mm], for example, in the range of 8.9 [mm] to 12.4 [mm], for example, 10.7 [mm].

[0113] If the shape of the battery cells 126, 128, 130, 132, 134, and 136 is of type 21700, the length L3 from the front end to the rear end of the positive power terminal 164 (or negative power terminal 166) is in the range of 4.0 [mm] to 22.0 [mm], for example, in the range of 10.6 [mm] to 19.6 [mm], for example, 17.1 [mm]. The length L4 from the front end to the rear end of the casing 144 is in the range of 87.0 [mm] to 96.0 [mm], for example, in the range of 89.1 [mm] to 93.6 [mm], for example, 91.1 [mm]. The ratio of the length L3 of the positive power terminal 164 (or negative power terminal 166) from front to rear to the length L4 of the casing 144 from front to rear is within the range of 4.2 [%] - 25.3 [%], for example, within the range of 11.3 [%] - 22.0 [%], for example, 18.8 [%]. The width W3 of the positive power terminal 164 (or negative power terminal 166) from right to left is within the range of 3.0 [mm] - 6.0 [mm], for example, within the range of 3.9 [mm] - 5.4 [mm], for example, 4.7 [mm]. The width W4 of the casing 144 from right to left is within the range of 70.0 [mm] - 78.0 [mm], for example, within the range of 72.1 [mm] - 76.1 [mm], for example, 74.1 [mm]. The ratio of the width W3 of the positive power terminal 164 (or negative power terminal 166) from right end to left end to the width W4 of the casing 144 from right end to left end is in the range of 3.8 [%] - 8.6 [%], for example, in the range of 5.1 [%] - 7.5 [%], for example, 6.3 [%]. The height H2 (see Figure 11) from the mounting surface of the positive power terminal 164 (or negative power terminal 166) (i.e., the top surface of the circuit board 140) to the top end of the positive power terminal 164 (or negative power terminal 166) is in the range of 7.0 [mm] - 14.0 [mm], for example, in the range of 8.9 [mm] - 12.4 [mm], for example, 10.7 [mm]. The height H2 (see Figure 11) from the mounting surface of the signal communication terminal 168 (i.e., the top surface of the circuit board 140) to the upper end of the signal communication terminal 168 is in the range of 7.0 [mm] to 14.0 [mm], for example, in the range of 8.9 [mm] to 12.4 [mm], for example, 10.7 [mm].

[0114] The lead plate 141 is joined to the positive cell terminal 90 or negative cell terminal 92 (see Figure 7) of the battery cells 126, 128, 130, 132, 134, and 136 by laser welding or spot welding. The thickness of the lead plate 141 is within the range of 0.10 [mm] - 1.00 [mm], for example, within the range of 0.31 [mm] - 1.00 [mm], for example, 0.50 [mm], or within the range of 0.10 [mm] - 0.19 [mm], within the range of 0.20 [mm] - 0.29 [mm], within the range of 0.30 [mm] - 0.39 [mm], within the range of 0.40 [mm] - 0.49 [mm], within the range of 0.50 [mm] - 0.59 [mm], within the range of 0.60 [mm] - 0.69 [mm], within the range of 0.70 [mm] - 0.79 [mm], within the range of 0.80 [mm] - 0.89 [mm], or within the range of 0.90 [mm] - 1.00 [mm]. The conductivity of the lead plate 141 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 31 [%IACS] to 106 [%IACS], for example, 40 [%IACS].

[0115] If the shape of the battery cells 126, 128, 130, 132, 134, and 136 is of the 18650 type, the weight of the battery pack 16 is in the range of 330 [g] - 480 [g], for example, in the range of 350 [g] - 450 [g], for example, 400 [g], or in the range of 330 [g] - 480 [g], for example, in the range of 365 [g] - 385 [g], for example, 375 [g]. In this case, the rated voltage of the battery pack 16 is in the range of 9.72 [V] - 11.88 [V], for example, in the range of 10.26 [V] - 11.34 [V], for example, 10.8 [V]. The rated capacity of the battery pack 16 is in the range of 4.0 [Ah] - 8.0 [Ah], for example, in the range of 4.0 [Ah] - 7.0 [Ah], for example, 6.0 [Ah], or in the range of 4.0 [Ah] - 12.0 [Ah], for example, in the range of 8.0 [Ah] - 12.0 [Ah], for example, 10.0 [Ah]. The energy capacity of the battery pack 16 is in the range of 38.9 [Wh] - 95.0 [Wh], for example, in the range of 43.2 [Wh] - 75.6 [Wh], for example, 64.8 [Wh], or in the range of 38.88 [Wh] - 142.56 [Wh], for example, in the range of 82.08 [Wh] - 136.08 [Wh], for example, 108 [Wh]. The continuous discharge output of the battery pack 16 is in the range of 690 [W] - 1610 [W], for example, in the range of 690 [W] - 1530 [W], for example, in the range of 820 [W] - 1180 [W], for example, 900 [W]. The continuous discharge output per unit mass of the battery pack 16 is in the range of 1.4 [W / g] - 4.9 [W / g], for example, in the range of 1.7 [W / g] - 4.0 [W / g], for example, in the range of 2.0 [W / g] - 2.9 [W / g], for example, 2.2 [W / g], or in the range of 1.5 [W / g] - 4.0 [W / g], for example, in the range of 1.8 [W / g] - 4.0 [W / g], for example, 2.5 [W / g].

[0116] If the shape of battery cells 126, 128, 130, 132, 134, and 136 is of type 21700, the weight of the battery pack 16 is in the range of 450 [g] - 630 [g], for example, in the range of 450 [g] - 600 [g], for example, 500 [g]. In this case, the rated voltage of the battery pack 16 is in the range of 9.72 [V] - 11.88 [V], for example, in the range of 10.26 [V] - 11.34 [V], for example, 10.8 [V]. The rated capacity of the battery pack 16 is in the range of 6.0 [Ah] - 12.0 [Ah], for example, in the range of 6.0 [Ah] - 11.0 [Ah], for example, 10.0 [Ah], or in the range of 4.0 [Ah] - 12.0 [Ah], for example, in the range of 8.0 [Ah] - 12.0 [Ah], for example, 10.0 [Ah]. The energy capacity of the battery pack 16 is in the range of 58.3 [Wh] - 142.6 [Wh], for example, in the range of 64.8 [Wh] - 118.8 [Wh], for example, 108.0 [Wh], or in the range of 38.88 [Wh] - 142.56 [Wh], for example, in the range of 82.08 [Wh] - 136.08 [Wh], for example, 108.0 [Wh]. The continuous discharge output of the battery pack 16 is in the range of 900 [W] - 2350 [W], for example, in the range of 900 [W] - 2190 [W], for example, in the range of 1080 [W] - 1640 [W], for example, 1240 [W]. The continuous discharge output per unit mass of the battery pack 16 is in the range of 1.4 [W / g] - 5.2 [W / g], for example, in the range of 1.8 [W / g] - 4.7 [W / g], for example, in the range of 2.1 [W / g] - 3.2 [W / g], for example, 2.4 [W / g], or in the range of 1.5 [W / g] - 4.0 [W / g], for example, in the range of 1.8 [W / g] - 4.0 [W / g], for example, 2.5 [W / g].

[0117] Figure 46 shows an example of the circuit configuration of the battery pack 16 and the electrical device 10. Similar to the battery pack 12, the battery pack 16 further includes a fuse link 330, a cell temperature detection circuit 332, a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. The power supply circuit 334, the current detection circuit 336, the AFE 338, the MCU 340, the voltage detection circuit 342, the protection FET circuit 344, the FET temperature detection circuit 346, the charger detection circuit 348, and the input / output control circuit 350 are provided on the circuit board 140.

[0118] The total number of pins in the MCU340 of the battery pack 16 is in the range of 33-100, for example, in the range of 33-60, for example, 48. The ROM capacity of the MCU340 of the battery pack 16 is in the range of 64 [kByte]-1024 [kByte], for example, in the range of 64 [kByte]-256 [kByte], for example, 128 [kByte]. The RAM capacity of the MCU340 of the battery pack 16 is in the range of 5 [kByte]-32 [kByte], for example, in the range of 6 [kByte]-16 [kByte], for example, 7 [kByte]. The CPU clock frequency of the MCU 340 of the battery pack 16 is in the range of 19.3 [MHz] - 128.0 [MHz], for example, in the range of 25.6 [MHz] - 48.0 [MHz], for example, 32.0 [MHz]. The number of parallel FETs in the protection FET circuit 344 of the battery pack 16 is in the range of 0 - 4, for example, in the range of 1 - 4, for example, in the range of 2 - 3, for example, 2. The ON resistance of each FET in the protection FET circuit 344 of the battery pack 16 is in the range of 0.10 [mΩ] - 0.59 [mΩ], for example, in the range of 0.30 [mΩ] - 0.50 [mΩ], for example, 0.45 [mΩ]. The total ON resistance of the protection FET circuit 344 of the battery pack 16 is in the range of 0.05 [mΩ] - 0.29 [mΩ], for example, in the range of 0.15 [mΩ] - 0.25 [mΩ], for example, 0.23 [mΩ].

[0119] (Configuration of Battery Pack 18) Battery pack 18 has a configuration that is almost identical to that of battery pack 16. The following mainly describes the differences between battery pack 18 and battery pack 16.

[0120] As shown in Figure 12, the battery pack 18 is equipped with battery cells 170, 172, 174, 176, 178, and 180 instead of battery cells 126, 128, 130, 132, 134, and 136. The battery cells 170, 172, 174, 176, 178, and 180 are arranged in two rows vertically and three columns horizontally, with their longitudinal direction aligned with the front-to-back direction. Battery cells 170 and 172 are electrically connected in parallel via lead plates 141 to form a battery cell pair 182. Battery cells 174 and 176 are electrically connected in parallel via lead plates 141 to form a battery cell pair 184. Battery cells 178 and 180 are electrically connected in parallel via lead plates 141 to form a battery cell pair 186. Battery cell pairs 182, 184, and 186 are electrically connected in series via lead plates 141.

[0121] Battery cells 170, 172, 174, 176, 178, and 180 all have the same configuration as battery cell 100 of battery pack 14. That is, battery cells 170, 172, 174, 176, 178, and 180 are tab-type battery cells.

[0122] If the shape of the battery cells 170, 172, 174, 176, 178, and 180 is of the 18650 type, the weight of the battery pack 18 is in the range of 330 [g] - 480 [g], for example, in the range of 350 [g] - 450 [g], for example, 400 [g]. In this case, the rated voltage of the battery pack 18 is in the range of 9.72 [V] - 11.88 [V], for example, in the range of 10.26 [V] - 11.34 [V], for example, 10.8 [V]. The rated capacity of the battery pack 18 is in the range of 4.0 [Ah] - 8.0 [Ah], for example, in the range of 4.0 [Ah] - 7.0 [Ah], for example, 6.0 [Ah], or in the range of 4.0 [Ah] - 12.0 [Ah], for example, in the range of 8.0 [Ah] - 12.0 [Ah], for example, 10.0 [Ah]. The energy capacity of the battery pack 18 is in the range of 38.9 [Wh] - 95.0 [Wh], for example, in the range of 43.2 [Wh] - 75.6 [Wh], for example, 64.8 [Wh], or in the range of 38.88 [Wh] - 142.56 [Wh], for example, in the range of 82.08 [Wh] - 136.08 [Wh], for example, 108 [Wh]. The continuous discharge output of the battery pack 18 is in the range of 180 [W] - 690 [W], for example, in the range of 210 [W] - 690 [W], for example, in the range of 350 [W] - 560 [W], for example, 470 [W]. The continuous discharge output per unit mass of the battery pack 18 is in the range of 0.4 [W / g] - 2.1 [W / g], for example, in the range of 0.4 [W / g] - 1.7 [W / g], for example, in the range of 0.8 [W / g] - 1.4 [W / g], for example, 1.1 [W / g], or in the range of 0.75 [W / g] - 1.8 [W / g], for example, in the range of 1.0 [W / g] - 1.6 [W / g], for example, 1.2 [W / g].

[0123] If the shape of battery cells 170, 172, 174, 176, 178, and 180 is of type 21700, the weight of the battery pack 18 is in the range of 450 [g] - 630 [g], for example, in the range of 450 [g] - 600 [g], for example, 500 [g], or in the range of 450 [g] - 630 [g], for example, in the range of 500 [g] - 600 [g], for example, 550 [g]. In this case, the rated voltage of the battery pack 18 is in the range of 9.72 [V] - 11.88 [V], for example, in the range of 10.26 [V] - 11.34 [V], for example, 10.8 [V]. The rated capacity of the battery pack 18 is in the range of 6.0 [Ah] - 12.0 [Ah], for example, in the range of 6.0 [Ah] - 11.0 [Ah], for example, 10.0 [Ah], or in the range of 4.0 [Ah] - 12.0 [Ah], for example, in the range of 8.0 [Ah] - 12.0 [Ah], for example, 10.0 [Ah]. The energy capacity of the battery pack 18 is in the range of 58.3 [Wh] - 142.6 [Wh], for example, in the range of 64.8 [Wh] - 118.8 [Wh], for example, 108.0 [Wh], or in the range of 38.88 [Wh] - 142.56 [Wh], for example, in the range of 82.08 [Wh] - 136.08 [Wh], for example, 108.0 [Wh]. The continuous discharge output of the battery pack 18 is in the range of 180 [W] - 890 [W], for example, in the range of 210 [W] - 890 [W], for example, in the range of 380 [W] - 730 [W], for example, 590 [W]. The continuous discharge output per unit mass of the battery pack 18 is in the range of 0.3 [W / g] - 2.0 [W / g], for example, in the range of 0.3 [W / g] - 1.7 [W / g], for example, in the range of 0.7 [W / g] - 1.4 [W / g], for example, 1.1 [W / g], or in the range of 0.75 [W / g] - 1.8 [W / g], for example, in the range of 1.0 [W / g] - 1.6 [W / g], for example, 1.2 [W / g].

[0124] In the battery pack 18, the height H2 (see Figure 11) from the mounting surface of the positive power terminal 164 (or negative power terminal 166) (i.e., the upper surface of the circuit board 140) to the upper end of the positive power terminal 164 (or negative power terminal 166) is in the range of 7.0 [mm] to 14.0 [mm], for example, in the range of 8.9 [mm] to 12.4 [mm], for example, 10.7 [mm]. In the battery pack 18, the plate thickness of the positive power terminal 164 (or negative power terminal 166) is in the range of 0.30 [mm] - 0.64 [mm], for example, in the range of 0.30 [mm] - 0.59 [mm], for example, in the range of 0.40 [mm] - 0.55 [mm], for example, 0.50 [mm], or in the range of 0.30 [mm] - 1.00 [mm], for example, in the range of 0.30 [mm] - 0.64 [mm], for example, in the range of 0.30 [mm] - 0.59 [mm], for example, 0.45 [mm]. In the battery pack 18, the conductivity of the positive power terminal 164 (or negative power terminal 166) is in the range of 1 [%IACS] - 106 [%IACS], for example, in the range of 1 [%IACS] - 30 [%IACS], for example, 25 [%IACS].

[0125] In the battery pack 18, the lead plate 141 is joined to the positive cell terminal 122 or negative cell terminal 124 (see Figure 7) of the battery cells 170, 172, 174, 176, 178, and 180 by spot welding. In the battery pack 18, the thickness of the lead plate 141 is within the range of 0.10 [mm] - 1.00 [mm], for example, within the range of 0.10 [mm] - 0.30 [mm], for example, 0.20 [mm], or within the range of 0.10 [mm] - 0.19 [mm], within the range of 0.20 [mm] - 0.29 [mm], within the range of 0.30 [mm] - 0.39 [mm], within the range of 0.40 [mm] - 0.49 [mm], within the range of 0.50 [mm] - 0.59 [mm], within the range of 0.60 [mm] - 0.69 [mm], within the range of 0.70 [mm] - 0.79 [mm], within the range of 0.80 [mm] - 0.89 [mm], or within the range of 0.90 [mm] - 1.00 [mm]. In the battery pack 18, the conductivity of the lead plate 141 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 1 [%IACS] to 30 [%IACS], for example, 25 [%IACS].

[0126] As shown in Figure 46, the battery pack 18, like the battery pack 16, further includes a fuse link 330, a cell temperature detection circuit 332, a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. Note that the battery pack 18 does not necessarily have a fuse link 330. Also, the battery pack 18 does not necessarily have a circuit board 140. Therefore, the battery pack 18 does not necessarily have a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. In this case, the cell temperature detection circuit 332 and the positive cell terminals 122 and / or negative cell terminals 124 (see Figure 7) of each battery cell 170, 172, 174, 176, 178, 180 may be directly connected to the signal communication terminal 168.

[0127] The total number of pins of the MCU340 in the battery pack 18 is in the range of 6 to 32, for example, in the range of 16 to 32, for example, 32. The ROM capacity of the MCU340 in the battery pack 18 is in the range of 8 [kByte] to 63 [kByte], for example, in the range of 16 [kByte] to 32 [kByte], for example, 32 [kByte]. The RAM capacity of the MCU340 in the battery pack 18 is in the range of 1 [kByte] to 4 [kByte], for example, in the range of 2 [kByte] to 4 [kByte], for example, 4 [kByte]. The CPU clock frequency of the MCU340 in the battery pack 18 is in the range of 4.8 [MHz] to 19.2 [MHz], for example, in the range of 14.4 [MHz] to 17.6 [MHz], for example, 16.0 [MHz]. The number of FETs in parallel in the protection FET circuit 344 of the battery pack 18 is in the range of 0-3, for example, in the range of 0-2, for example, in the range of 1-2, for example, 1. The ON resistance of each FET in the protection FET circuit 344 of the battery pack 18 is in the range of 0.60 [mΩ]-5.00 [mΩ], for example, in the range of 0.60 [mΩ]-1.00 [mΩ], for example, 0.65 [mΩ]. The total ON resistance of the protection FET circuit 344 of the battery pack 18 is in the range of 0.30 [mΩ]-5.00 [mΩ], for example, in the range of 0.30 [mΩ]-0.50 [mΩ], for example, 0.33 [mΩ].

[0128] The features of the battery packs 12 and 14 in this embodiment are summarized in Tables 1 and 2 below.

[0129]

[0130]

[0131] The features of the battery packs 16 and 18 in this embodiment are summarized in Tables 3 and 4 below.

[0132]

[0133]

[0134] (Example 2) As shown in Figure 15, the electrical equipment system 202 of this embodiment comprises an electrical device 210 and battery packs 212, 214, 216, and 218. One of the battery packs 212, 214, 216, and 218 can be selectively attached to the electrical device 210. The electrical device 210 is an electrical device that operates using power supplied from the battery packs 212, 214, 216, and 218. The electrical device 210 may be, for example, a power tool that uses a motor as a power source, such as a driver drill or an impact driver, or a motor-powered work machine that uses a motor as a power source, such as a hedge trimmer or a hand saw. Alternatively, the electrical device 210 may be an electrical device that does not have a motor, such as a light, radio, or speaker. Alternatively, the electrical device 210 may be a charger that charges the battery packs 212, 214, 216, and 218.

[0135] (Configuration of the electrical device 210) As shown in Figures 16 and 17, the electrical device 210 is equipped with a battery pack mounting section 220. The battery packs 212, 214, 216, and 218 can be attached to the battery pack mounting section 220 by inserting them into the battery pack mounting section 220 in a predetermined insertion direction. That is, the battery packs 212, 214, 216, and 218 are stick-type battery packs. Hereinafter, the direction in which the battery packs 212, 214, 216, and 218 are inserted when attaching them to the battery pack mounting section 220 will be referred to as the upward direction, and the direction in which the battery packs 212, 214, 216, and 218 are removed from the battery pack mounting section 220 will be referred to as the downward direction. Furthermore, the direction perpendicular to the vertical direction is called the front-back direction, and the direction perpendicular to both the front-back and vertical directions is called the left-right direction.

[0136] As shown in Figure 18, the battery pack mounting portion 220 is provided with an insertion recess 222, a device-side terminal 224, and an engagement groove 226. The insertion recess 222 has a shape that allows it to engage with the insertion protrusion 254 (see Figures 21 and 23) of the battery packs 212, 214, 216, and 218 so as to be movable in the vertical direction. The device-side terminal 224 is provided on the upper bottom surface of the insertion recess 222. The device-side terminal 224 is equipped with a positive power terminal 228 and a negative power terminal 230 for charging or discharging power between the electrical equipment 210 and the battery packs 212, 214, 216, and 218. The device-side terminal 224 may also be equipped with a signal communication terminal (not shown) for signal communication between the electrical equipment 210 and the battery packs 212, 214, 216, and 218. The engagement groove 226 is equipped with a right-side engagement groove 232 and a left-side engagement groove 234. The right-side engagement groove 232 is formed on the inner right side of the insertion recess 222 and is recessed toward the right. The left-side engagement groove 234 is formed on the inner left side of the insertion recess 222 and is recessed toward the left.

[0137] (Configuration of Battery Pack 212) As shown in Figure 19, the battery pack 212 comprises battery cells 236, 238, 240 (see Figure 20), a cell holder 242, a circuit board 244, a lead plate 245, battery-side terminals 246, and a casing 248. As shown in Figure 20, the battery cells 236, 238, 240 are arranged so that their longitudinal direction is aligned with the vertical direction. The battery cells 238, 240 are arranged side by side to the left and right behind the battery cell 236. The battery cells 236, 238, 240 are electrically connected in series via the lead plate 245. The cell holder 242 holds the battery cells 236, 238, 240. The circuit board 244 is held by the cell holder 242 above the cell holder 242 and is electrically connected to the battery cells 236, 238, 240 via the lead plate 245. The battery-side terminal 246 is held by the cell holder 242 above the cell holder 242 and is electrically connected to the circuit board 244. As shown in Figure 19, the casing 248 houses the battery cells 236, 238, 240, the cell holder 242, the circuit board 244, the lead plate 245, and the battery-side terminal 246.

[0138] As shown in Figure 21, the casing 248 comprises a lower casing 250 and an upper casing 252. The upper casing 252 has an insertion projection 254 and a terminal opening 256. The insertion projection 254 has a shape corresponding to the insertion recess 222 (see Figure 18) of the battery pack mounting portion 220. The insertion projection 254 is located at the upper end of the upper casing 252 and comprises a primary tip surface 254a that extends planarly in the front-rear and left-right directions, a primary side surface 254b that extends downward from the periphery of the primary tip surface 254a, a secondary tip surface 254c that is located below the primary tip surface 254a and extends planarly in the front-rear and left-right directions, and a secondary side surface 254d that extends downward from the periphery of the secondary tip surface 254c. The terminal opening 256 is positioned to correspond to the device-side terminal 224 (see Figure 18) of the battery pack mounting portion 220, and has a shape that allows the device-side terminal 224 to pass through when the battery pack 212 is attached to the electrical device 210.

[0139] An engaging piece 258 is formed on the lower casing 250. The engaging piece 258 engages with the engagement groove 226 (see Figure 18) of the battery pack mounting portion 220 when the insertion projection 254 of the engaging piece 258 is inserted into the insertion recess 222 of the battery pack mounting portion 220. The engaging piece 258 is located on the right side of the lower casing 250 and includes an elastically deformable right-side engaging piece 260 and an elastically deformable left-side engaging piece 262 located on the left side of the lower casing 250. The right-side engaging piece 260 includes a right-side engaging portion 264 that can engage with the right-side engagement groove 232 (see Figure 18) of the battery pack mounting portion 220, and a right-side operating portion 266 for releasing the engagement between the right-side engagement groove 232 and the right-side engaging portion 264. The left-side engaging piece 262 includes a left-side engaging portion 268 that can engage with the left-side engaging groove 234 (see Figure 18) of the battery pack mounting portion 220, and a left-side operating portion 270 for releasing the engagement between the left-side engaging groove 234 and the left-side engaging portion 268.

[0140] As shown in Figure 20, the battery cells 236, 238, and 240 all have the same configuration as the battery cell 40 of the battery pack 12 of Embodiment 1. That is, the battery cells 236, 238, and 240 are tablet-type battery cells. In the battery pack 212 of this embodiment, the battery cells 236, 238, and 240 are housed in insertion protrusions 254 (see Figure 21) which have a shape corresponding to the insertion recess 222 (see Figure 18) of the electrical device 210. For this reason, the shape of the battery cells 236, 238, and 240 is the 18650 type, which fits inside the insertion protrusions 254, and not the 21700 type.

[0141] The battery pack 212 is a stick-type battery pack, and when the battery pack 212 is attached to the electrical device 210, the insertion protrusion 254 that houses the battery cells 236, 238, and 240 is positioned inside the insertion recess 222 of the electrical device 210. This allows the size of the electrical device 210 to be reduced when the battery pack 212 is attached. Furthermore, if the insertion recess 222 of the electrical device 210 is located inside the grip portion that the user holds the electrical device 210 in, there is no need to provide a separate insertion recess 222, so the size of the electrical device 210 can be reduced even further.

[0142] The battery-side terminal 246 includes a positive power terminal 272 and a negative power terminal 274 for charging or discharging power between the electrical device 210 and the battery pack 212, and signal communication terminals 276, 278, and 280 for signal communication between the electrical device 210 and the battery pack 212. The positive power terminal 272 and the negative power terminal 274 are positioned to correspond to the positive power terminal 228 and the negative power terminal 230 (see Figure 18) of the electrical device 210. The signal communication terminals 276, 278, and 280 are positioned to correspond to the signal communication terminals (not shown) of the electrical device 210. When the battery pack 212 is attached to the electrical equipment 210, the positive power terminal 272 and the negative power terminal 274 mechanically engage with and electrically connect to the positive power terminal 228 and the negative power terminal 230 of the electrical equipment 210 by clamping them from the left and right directions, respectively. When the battery pack 212 is attached to the electrical equipment 210, the signal communication terminals 276, 278, and 280 electrically connect to the corresponding signal communication terminals (not shown) of the electrical equipment 210 by contacting them.

[0143] As shown in Figure 21, terminal openings 256 corresponding to the positive power terminal 272 and the negative power terminal 274 are located on the primary end surface 254a. Terminal openings 256 corresponding to the signal communication terminal 276 are located so as to span the primary end surface 254a and the primary side surface 254b. Terminal openings 256 corresponding to the signal communication terminals 278 and 280 are located so as to span the secondary end surface 254c and the secondary side surface 254d.

[0144] As shown in Figure 22, the length from the front end to the rear end of the positive power terminal 272 is the same as the length from the front end to the rear end of the negative power terminal 274. The width from the right end to the left end of the positive power terminal 272 is the same as the width from the right end to the left end of the negative power terminal 274. The height from the mounting surface of the positive power terminal 272 (i.e., the top surface of the cell holder 242) to the top end of the positive power terminal 272 is the same as the height from the mounting surface of the negative power terminal 274 (i.e., the top surface of the cell holder 242) to the top end of the negative power terminal 274.

[0145] The length L5 from the front end to the rear end of the positive power terminal 272 (or negative power terminal 274) is in the range of 3.0 [mm] - 13.0 [mm], for example, in the range of 6.5 [mm] - 11.5 [mm], for example, 10.0 [mm]. The length L6 from the front end to the rear end of the insertion projection 254 of the casing 248 is in the range of 35.0 [mm] - 40.0 [mm], for example, in the range of 36.0 [mm] - 39.0 [mm], for example, 37.6 [mm]. The ratio of the length L5 from the front end to the rear end of the positive power terminal 272 (or negative power terminal 274) to the length L6 from the front end to the rear end of the insertion projection 254 of the casing 248 is in the range of 7.5 [%] - 37.1 [%], for example, in the range of 16.7 [%] - 31.9 [%], for example, 26.6 [%]. The length L7 of the engaging piece 258 of the casing 248 from the front end to the rear end is in the range of 46.0 [mm] - 50.0 [mm], for example, in the range of 47.0 [mm] - 49.0 [mm], for example, 48.0 [mm]. The width W5 of the positive power terminal 272 (or negative power terminal 274) from the right end to the left end is in the range of 3.0 [mm] - 7.0 [mm], for example, in the range of 4.0 [mm] - 6.0 [mm], for example, 5.0 [mm]. The width W6 of the insertion projection 254 of the casing 248 from the right end to the left end is in the range of 38.0 [mm] - 42.0 [mm], for example, in the range of 39.0 [mm] - 41.0 [mm], for example, 40.0 [mm]. The ratio of the width W5 of the positive power terminal 272 (or negative power terminal 274) from right end to left end to the width W6 of the insertion projection 254 of the casing 248 from right end to left end is in the range of 7.1 [%] - 18.4 [%], for example, in the range of 9.8 [%] - 15.4 [%], for example, 12.5 [%]. The width W7 of the engaging piece 258 of the casing 248 from right end to left end is in the range of 45.0 [mm] - 52.0 [mm], for example, in the range of 46.0 [mm] - 49.0 [mm], for example, 47.0 [mm].The height H3 (see Figure 19) from the mounting surface of the positive power terminal 272 (or negative power terminal 274) (i.e., the upper surface of the cell holder 242) to the upper end of the positive power terminal 272 (or negative power terminal 274) is in the range of 3.0 [mm] to 15.0 [mm], for example, in the range of 8.6 [mm] to 15.0 [mm], for example, 10.0 [mm]. The height H4 from the lower end of the casing 248 to the primary tip surface 254a is in the range of 81.0 [mm] to 90.0 [mm], for example, in the range of 83.0 [mm] to 88.0 [mm], for example, 86.0 [mm]. The height H5 from the lower end of the casing 248 to the secondary tip surface 254c is within the range of 72.0 [mm] - 80.0 [mm], for example, within the range of 74.0 [mm] - 78.0 [mm], for example, 76.0 [mm]. The height H6 from the engagement surfaces of the right engagement portion 264 and left engagement portion 268 of the casing 248 to the primary tip surface 254a is within the range of 40.0 [mm] - 44.0 [mm], for example, within the range of 41.0 [mm] - 43.0 [mm], for example, 42.0 [mm]. The height H7 from the engagement surfaces of the right engagement portion 264 and left engagement portion 268 of the casing 248 to the secondary tip surface 254c is within the range of 31.0 [mm] - 41.0 [mm], for example, within the range of 32.0 [mm] - 37.0 [mm], for example, 33.0 [mm].

[0146] The plate thickness of the positive power terminal 272 (or negative power terminal 274) is in the range of 0.60 [mm] - 1.00 [mm], for example, in the range of 0.65 [mm] - 1.00 [mm], for example, in the range of 0.65 [mm] - 0.80 [mm], for example, 0.80 [mm], or in the range of 0.30 [mm] - 1.00 [mm], for example, in the range of 0.60 [mm] - 1.00 [mm], for example, in the range of 0.65 [mm] - 1.00 [mm], for example, 0.80 [mm]. The conductivity of the positive power terminal 272 (or negative power terminal 274) is in the range of 1 [%IACS] - 106 [%IACS], for example, in the range of 31 [%IACS] - 106 [%IACS], for example, 40 [%IACS]. The plate thickness of the signal communication terminals 276, 278, and 280 is in the range of 0.30 [mm] to 1.00 [mm], for example, in the range of 0.30 [mm] to 0.64 [mm], for example, in the range of 0.30 [mm] to 0.59 [mm], and for example, 0.45 [mm]. The conductivity of the signal communication terminals 276, 278, and 280 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 1 [%IACS] to 30 [%IACS], and for example, 25 [%IACS].

[0147] The lead plate 245 is joined to the positive cell terminal 90 or negative cell terminal 92 (see Figure 7) of the battery cells 236, 238, and 240 by laser welding or spot welding. The thickness of the lead plate 245 is within the range of 0.10 [mm] - 1.00 [mm], for example, within the range of 0.31 [mm] - 1.00 [mm], for example, 0.50 [mm], or within the range of 0.10 [mm] - 0.19 [mm], within the range of 0.20 [mm] - 0.29 [mm], within the range of 0.30 [mm] - 0.39 [mm], within the range of 0.40 [mm] - 0.49 [mm], within the range of 0.50 [mm] - 0.59 [mm], within the range of 0.60 [mm] - 0.69 [mm], within the range of 0.70 [mm] - 0.79 [mm], within the range of 0.80 [mm] - 0.89 [mm], or within the range of 0.90 [mm] - 1.00 [mm]. The conductivity of the lead plate 245 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 31 [%IACS] to 106 [%IACS], for example, 40 [%IACS].

[0148] The weight of the battery pack 212 is in the range of 150 g - 240 g, for example, in the range of 170 g - 220 g, for example, 200 g, or in the range of 150 g - 240 g, for example, in the range of 160 g - 180 g, for example, 170 g. In this case, the rated voltage of the battery pack 212 is in the range of 9.72 V - 11.88 V, for example, in the range of 10.26 V - 11.34 V, for example, 10.8 V. The rated capacity of the battery pack 212 is in the range of 2.0 [Ah] - 4.0 [Ah], for example, in the range of 2.0 [Ah] - 3.5 [Ah], for example, 3.0 [Ah], or in the range of 2.0 [Ah] - 6.0 [Ah], for example, 4.0 [Ah] - 6.0 [Ah], for example, 5.0 [Ah]. The energy capacity of the battery pack 212 is in the range of 19.4 [Wh] - 47.5 [Wh], for example, in the range of 21.6 [Wh] - 37.8 [Wh], for example, 32.4 [Wh], or in the range of 19.44 [Wh] - 71.28 [Wh], for example, in the range of 41.04 [Wh] - 68.04 [Wh], for example, 54 [Wh]. The continuous discharge output of the battery pack 212 is in the range of 350 [W] - 800 [W], for example, in the range of 350 [W] - 770 [W], for example, in the range of 410 [W] - 590 [W], for example, 450 [W]. The continuous discharge output per unit mass of the battery pack 212 is in the range of 1.5 [W / g] - 5.3 [W / g], for example, in the range of 1.7 [W / g] - 4.0 [W / g], for example, in the range of 2.0 [W / g] - 2.9 [W / g], for example, 2.2 [W / g], or in the range of 1.5 [W / g] - 4.0 [W / g], for example, in the range of 1.8 [W / g] - 4.0 [W / g], for example, 3.0 [W / g].

[0149] Figure 47 shows an example of the circuit configuration of the battery pack 212 and the electrical device 210. In Figure 47, the positive power terminal 272 and negative power terminal 274 of the battery-side terminal 246, and the signal communication terminals 276, 278, and 280 are shown as examples of a configuration in which these are connected to the wiring on the circuit board 244. The battery pack 212, like the battery pack 12 of Embodiment 1, further includes a fuse link 330, a cell temperature detection circuit 332, a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. The power supply circuit 334, current detection circuit 336, AFE 338, MCU 340, voltage detection circuit 342, protection FET circuit 344, FET temperature detection circuit 346, charger detection circuit 348, and input / output control circuit 350 are provided on the circuit board 244.

[0150] The electrical device 210, like the electrical device 10 in Embodiment 1, includes a power supply circuit 352, an MCU 354, an LED 356, a trigger switch 358, a motor control circuit 360, a motor drive circuit 362, an electric motor 364, a protection FET circuit 366, and an FET control circuit 368.

[0151] The total number of pins in the MCU 340 of the battery pack 212 is in the range of 33-100, for example, in the range of 33-60, for example, 48. The ROM capacity of the MCU 340 of the battery pack 212 is in the range of 64 [kByte]-1024 [kByte], for example, in the range of 64 [kByte]-256 [kByte], for example, 128 [kByte]. The RAM capacity of the MCU 340 of the battery pack 212 is in the range of 5 [kByte]-32 [kByte], for example, in the range of 6 [kByte]-16 [kByte], for example, 7 [kByte]. The CPU clock frequency of the MCU 340 of the battery pack 212 is in the range of 19.3 [MHz] - 128.0 [MHz], for example, in the range of 25.6 [MHz] - 48.0 [MHz], for example, 32.0 [MHz]. The number of parallel FETs in the protection FET circuit 344 of the battery pack 212 is in the range of 0 - 4, for example, in the range of 1 - 4, for example, in the range of 2 - 3, for example, 2. The ON resistance of each FET in the protection FET circuit 344 of the battery pack 212 is in the range of 0.10 [mΩ] - 0.59 [mΩ], for example, in the range of 0.30 [mΩ] - 0.50 [mΩ], for example, 0.45 [mΩ]. The total ON resistance of the protection FET circuit 344 of the battery pack 212 is in the range of 0.05 [mΩ] to 0.29 [mΩ], for example, in the range of 0.15 [mΩ] to 0.25 [mΩ], for example, 0.23 [mΩ].

[0152] (Configuration of Battery Pack 214) Battery pack 214 has a configuration that is almost identical to that of battery pack 212. The following mainly describes the differences between battery pack 214 and battery pack 212.

[0153] As shown in Figure 20, the battery pack 214 has battery cells 282, 284, and 286 instead of battery cells 236, 238, and 240. The battery cells 282, 284, and 286 are arranged so that their longitudinal direction is aligned with the vertical direction. The battery cells 284 and 286 are arranged side by side, left to right, behind the battery cell 282. The battery cells 282, 284, and 286 are electrically connected in series.

[0154] The battery cells 282, 284, and 286 all have the same configuration as the battery cell 100 of the battery pack 14 of Embodiment 1. That is, the battery cells 282, 284, and 286 are tab-type battery cells. In the battery pack 214 of this embodiment, the battery cells 282, 284, and 286 are housed in insertion protrusions 254 (see Figure 21) which have a shape corresponding to the insertion recess 222 (see Figure 18) of the electrical device 210. For this reason, the shape of the battery cells 282, 284, and 286 is the 18650 type, which fits inside the insertion protrusions 254, and not the 21700 type.

[0155] The weight of the battery pack 214 is in the range of 150 g - 240 g, for example, in the range of 170 g - 220 g, for example, 200 g. In this case, the rated voltage of the battery pack 214 is in the range of 9.72 V - 11.88 V, for example, in the range of 10.26 V - 11.34 V, for example, 10.8 V. The rated capacity of the battery pack 214 is in the range of 2.0 Ah - 4.0 Ah, for example, in the range of 2.0 Ah - 3.5 Ah, for example, 3.0 Ah, or in the range of 2.0 Ah - 6.0 Ah, for example, 4.0 Ah - 6.0 Ah, for example, 5.0 Ah. The energy capacity of the battery pack 214 is in the range of 19.4 [Wh] - 47.5 [Wh], for example, in the range of 21.6 [Wh] - 37.8 [Wh], for example, 32.4 [Wh], or in the range of 19.44 [Wh] - 71.28 [Wh], for example, in the range of 41.04 [Wh] - 68.04 [Wh], for example, 54 [Wh]. The continuous discharge output of the battery pack 214 is in the range of 90 [W] - 340 [W], for example, in the range of 110 [W] - 340 [W], for example, in the range of 170 [W] - 280 [W], for example, 230 [W]. The continuous discharge output per unit mass of the battery pack 214 is in the range of 0.4 [W / g] - 2.3 [W / g], for example, in the range of 0.4 [W / g] - 1.7 [W / g], for example, in the range of 0.8 [W / g] - 1.4 [W / g], for example, 1.1 [W / g], or in the range of 0.75 [W / g] - 1.8 [W / g], for example, in the range of 1.0 [W / g] - 1.6 [W / g], for example, 1.2 [W / g].

[0156] In the battery pack 214, the height H3 (see Figure 19) from the mounting surface of the positive power terminal 272 (or negative power terminal 274) (i.e., the upper surface of the cell holder 242) to the upper end of the positive power terminal 272 (or negative power terminal 274) is within the range of 3.0 [mm] - 15.0 [mm], for example, within the range of 8.6 [mm] - 15.0 [mm], for example, 10.0 [mm], or within the range of 3.0 [mm] - 15.0 [mm], for example, within the range of 3.0 [mm] - 8.5 [mm], for example, 8.0 [mm]. In the battery pack 214, the plate thickness of the positive power terminal 272 (or negative power terminal 274) is in the range of 0.30 [mm] - 0.64 [mm], for example, in the range of 0.30 [mm] - 0.59 [mm], for example, in the range of 0.40 [mm] - 0.55 [mm], for example, 0.50 [mm], or in the range of 0.30 [mm] - 1.00 [mm], for example, in the range of 0.30 [mm] - 0.64 [mm], for example, in the range of 0.30 [mm] - 0.59 [mm], for example, 0.45 [mm]. In the battery pack 214, the conductivity of the positive power terminal 272 (or negative power terminal 274) is in the range of 1 [%IACS] - 106 [%IACS], for example, in the range of 1 [%IACS] - 30 [%IACS], for example, 25 [%IACS].

[0157] In the battery pack 214, the lead plate 245 is joined to the positive cell terminal 122 or negative cell terminal 124 (see Figure 7) of the battery cells 282, 284, and 286 by spot welding. In the battery pack 214, the thickness of the lead plate 245 is within the range of 0.10 [mm] - 1.00 [mm], for example, within the range of 0.10 [mm] - 0.30 [mm], for example, 0.20 [mm], or within the range of 0.10 [mm] - 0.19 [mm], within the range of 0.20 [mm] - 0.29 [mm], within the range of 0.30 [mm] - 0.39 [mm], within the range of 0.40 [mm] - 0.49 [mm], within the range of 0.50 [mm] - 0.59 [mm], within the range of 0.60 [mm] - 0.69 [mm], within the range of 0.70 [mm] - 0.79 [mm], within the range of 0.80 [mm] - 0.89 [mm], or within the range of 0.90 [mm] - 1.00 [mm]. In the battery pack 214, the conductivity of the lead plate 245 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 1 [%IACS] to 30 [%IACS], for example, 25 [%IACS].

[0158] As shown in Figure 47, the battery pack 214, like the battery pack 212, further includes a fuse link 330, a cell temperature detection circuit 332, a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. Note that the battery pack 214 does not necessarily have a fuse link 330. Also, the battery pack 214 does not necessarily have a circuit board 244. Therefore, the battery pack 214 does not necessarily have a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. In this case, the cell temperature detection circuit 332 and the positive cell terminals 122 and / or negative cell terminals 124 (see Figure 7) of each battery cell 282, 284, 286 may be directly connected to the signal communication terminals 276, 278, 280.

[0159] The total number of pins in the MCU 340 of the battery pack 214 is in the range of 6 to 32, for example, in the range of 16 to 32, for example, 32. The ROM capacity of the MCU 340 of the battery pack 214 is in the range of 8 [kByte] to 63 [kByte], for example, in the range of 16 [kByte] to 32 [kByte], for example, 32 [kByte]. The RAM capacity of the MCU 340 of the battery pack 214 is in the range of 1 [kByte] to 4 [kByte], for example, in the range of 2 [kByte] to 4 [kByte], for example, 4 [kByte]. The CPU clock frequency of the MCU 340 of the battery pack 214 is in the range of 4.8 [MHz] to 19.2 [MHz], for example, in the range of 14.4 [MHz] to 17.6 [MHz], for example, 16.0 [MHz]. The number of parallel FETs in the protection FET circuit 344 of the battery pack 214 is in the range of 0 to 3, for example, in the range of 0 to 2, for example, in the range of 1 to 2, for example, 1. The ON resistance of each FET in the protection FET circuit 344 of the battery pack 214 is in the range of 0.60 [mΩ] to 5.00 [mΩ], for example, in the range of 0.60 [mΩ] to 1.00 [mΩ], for example, 0.65 [mΩ]. The total ON resistance of the protection FET circuit 344 of the battery pack 214 is in the range of 0.30 [mΩ] to 5.00 [mΩ], for example, in the range of 0.30 [mΩ] to 0.50 [mΩ], for example, 0.33 [mΩ].

[0160] (Configuration of Battery Pack 216) Battery pack 216 has a configuration that is partially similar to that of battery pack 212. The following mainly describes the differences between battery pack 216 and battery pack 212.

[0161] As shown in Figure 23, the battery pack 216 comprises battery cells 288, 290, 292, 294, 296, and 298 (see Figures 24 and 25), a cell holder 242 (see Figure 20), a circuit board 244 (see Figure 20), a lead plate 245 (see Figure 20), battery-side terminals 246 (see Figure 20), and a casing 300. The casing 300 comprises a lower casing 302 and an upper casing 252. The lower casing 302 comprises an engaging piece 258 and a battery cell housing portion 304. As shown in Figure 24, the battery cells 288, 290, and 292 are housed in the insertion projection 254 of the upper casing 252. The battery cells 288, 290, and 292 are arranged so that their longitudinal direction is aligned with the vertical direction. Battery cells 290 and 292 are arranged side by side behind battery cell 288. Battery cells 288, 290, and 292 are electrically connected in series via lead plates 245 to form a battery cell assembly 306. As shown in Figure 25, battery cells 294, 296, and 298 are housed in the battery cell housing section 304 of the lower casing 302. Battery cells 294, 296, and 298 are arranged in one row vertically and three rows horizontally, with their longitudinal direction aligned with the front-to-back direction. Battery cells 294, 296, and 298 are electrically connected in series via lead plates 245 to form a battery cell assembly 308. Battery cell assemblies 306 and 308 are electrically connected in parallel via lead plates 245.

[0162] Battery cells 288, 290, 292, 294, 296, and 298 all have the same configuration as battery cell 40 of the battery pack 12 in Embodiment 1. That is, battery cells 288, 290, 292, 294, 296, and 298 are tablet-type battery cells. The shape of battery cells 288, 290, 292, 294, 296, and 298 is all of the 18650 type.

[0163] The weight of the battery pack 216 is in the range of 370 g - 500 g, for example, in the range of 400 g - 500 g, for example, 450 g. In this case, the rated voltage of the battery pack 216 is in the range of 9.72 V - 11.88 V, for example, in the range of 10.26 V - 11.34 V, for example, 10.8 V. The rated capacity of the battery pack 216 is in the range of 4.0 Ah - 8.0 Ah, for example, in the range of 4.0 Ah - 7.0 Ah, for example, 6.0 Ah, or in the range of 4.0 Ah - 12.0 Ah, for example, 6.0 Ah - 10.0 Ah, for example, 10.0 Ah. The energy capacity of the battery pack 216 is in the range of 38.9 [Wh] - 95.0 [Wh], for example, in the range of 43.2 [Wh] - 75.6 [Wh], for example, 64.8 [Wh], or in the range of 38.88 [Wh] - 142.56 [Wh], for example, 61.56 [Wh] - 113.40 [Wh], for example, 108.0 [Wh]. The continuous discharge output of the battery pack 216 is in the range of 690 [W] - 1610 [W], for example, in the range of 690 [W] - 1530 [W], for example, in the range of 820 [W] - 1180 [W], for example, 900 [W]. The continuous discharge output per unit mass of the battery pack 216 is within the range of 1.4 [W / g] - 4.4 [W / g], for example, within the range of 1.5 [W / g] - 3.5 [W / g], for example, within the range of 1.8 [W / g] - 2.6 [W / g], for example, 2.0 [W / g], or within the range of 1.5 [W / g] - 4.0 [W / g], for example, within the range of 1.8 [W / g] - 4.0 [W / g], for example, 3.5 [W / g].

[0164] As shown in Figure 24, in the battery pack 216, the length L8 from the front end of the casing 300 (i.e., the front end of the battery cell housing 304) to the rear end of the casing 300 (i.e., the rear end of the battery cell housing 304) is in the range of 83.0 [mm] - 92.0 [mm], for example, in the range of 85.0 [mm] - 89.0 [mm], for example, 87.0 [mm]. In the battery pack 216, the width W8 from the right end of the casing 300 (i.e., the right end of the battery cell housing 304) to the left end of the casing 300 (i.e., the left end of the battery cell housing 304) is in the range of 62.0 [mm] - 69.0 [mm], for example, in the range of 64.0 [mm] - 67.5 [mm], for example, 66.0 [mm].

[0165] As shown in Figure 25, the height H8 from the lower end of the casing 300 (i.e., the lower end of the battery cell housing 304) to the primary front end surface 254a is in the range of 105 [mm] - 116 [mm], for example, in the range of 108 [mm] - 113 [mm], for example, 111 [mm]. The height H9 from the lower end of the casing 300 (i.e., the lower end of the battery cell housing 304) to the secondary front end surface 254c is in the range of 96 [mm] - 107 [mm], for example, in the range of 99 [mm] - 104 [mm], for example, 102 [mm]. The height H10 from the lower end to the upper end of the battery cell housing 304 is in the range of 32.0 [mm] - 35.0 [mm], for example, in the range of 33.0 [mm] - 34.5 [mm], for example, 34.0 [mm].

[0166] In the battery pack 216, the height H3 (see Figure 19) from the mounting surface of the positive power terminal 272 (or negative power terminal 274) (i.e., the upper surface of the cell holder 242) to the upper end of the positive power terminal 272 (or negative power terminal 274) is within the range of 3.0 [mm] to 15.0 [mm], for example, within the range of 8.6 [mm] to 15.0 [mm], for example, 10.0 [mm]. In the battery pack 216, the plate thickness of the positive power terminal 272 (or negative power terminal 274) is within the range of 0.60 [mm] - 1.00 [mm], for example, within the range of 0.65 [mm] - 1.00 [mm], for example, within the range of 0.65 [mm] - 0.80 [mm], for example, 0.80 [mm], or within the range of 0.30 [mm] - 1.00 [mm], for example, within the range of 0.60 [mm] - 1.00 [mm], for example, within the range of 0.65 [mm] - 1.00 [mm], for example, 0.80 [mm]. In the battery pack 216, the conductivity of the positive power terminal 272 (or negative power terminal 274) is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 31 [%IACS] to 106 [%IACS], for example, 40 [%IACS].

[0167] In the battery pack 216, the lead plate 245 is joined to the positive cell terminal 90 or negative cell terminal 92 (see Figure 7) of the battery cells 288, 290, 292, 294, 296, and 298 by laser welding or spot welding. In the battery pack 216, the thickness of the lead plate 245 is within the range of 0.10 [mm] - 1.00 [mm], for example, within the range of 0.31 [mm] - 1.00 [mm], for example, 0.50 [mm], or within the range of 0.10 [mm] - 0.19 [mm], within the range of 0.20 [mm] - 0.29 [mm], within the range of 0.30 [mm] - 0.39 [mm], within the range of 0.40 [mm] - 0.49 [mm], within the range of 0.50 [mm] - 0.59 [mm], within the range of 0.60 [mm] - 0.69 [mm], within the range of 0.70 [mm] - 0.79 [mm], within the range of 0.80 [mm] - 0.89 [mm], or within the range of 0.90 [mm] - 1.00 [mm]. In the battery pack 216, the conductivity of the lead plate 245 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 31 [%IACS] to 106 [%IACS], for example, 40 [%IACS].

[0168] In this embodiment, the battery pack 216 houses the battery cells 288, 290, and 292 in insertion protrusions 254 that correspond to the insertion recesses 222 (see Figure 18) of the electrical device 210. Therefore, the shape of the battery cells 288, 290, and 292 must be of the 18650 type, which fits inside the insertion protrusions 254, and cannot be of the 21700 type. In contrast, the battery cells 288, 290, and 292 are housed in a battery cell housing section 304 that is located outside the insertion recesses 222 when the battery pack 216 is attached to the electrical device 210. Therefore, the shape of the battery cells 288, 290, and 292 may be of the 21700 type instead of the 18650 type. The shape and number of battery cells 288, 290, and 292 housed in the battery cell housing section 304 can be changed in various ways.

[0169] Figure 48 shows an example of the circuit configuration of the battery pack 216 and the electrical device 210. The battery pack 16, like the battery pack 212, further includes a fuse link 330, a cell temperature detection circuit 332, a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. The power supply circuit 334, the current detection circuit 336, the AFE 338, the MCU 340, the voltage detection circuit 342, the protection FET circuit 344, the FET temperature detection circuit 346, the charger detection circuit 348, and the input / output control circuit 350 are provided on the circuit board 244.

[0170] The total number of pins in the MCU 340 of the battery pack 216 is in the range of 33-100, for example, in the range of 33-60, for example, 48. The ROM capacity of the MCU 340 of the battery pack 216 is in the range of 64 [kByte]-1024 [kByte], for example, in the range of 64 [kByte]-256 [kByte], for example, 128 [kByte]. The RAM capacity of the MCU 340 of the battery pack 216 is in the range of 5 [kByte]-32 [kByte], for example, in the range of 6 [kByte]-16 [kByte], for example, 7 [kByte]. The CPU clock frequency of the MCU 340 of the battery pack 216 is in the range of 19.3 [MHz] - 128.0 [MHz], for example, in the range of 25.6 [MHz] - 48.0 [MHz], for example, 32.0 [MHz]. The number of parallel FETs in the protection FET circuit 344 of the battery pack 216 is in the range of 0 - 4, for example, in the range of 1 - 4, for example, in the range of 2 - 3, for example, 2. The ON resistance of each FET in the protection FET circuit 344 of the battery pack 216 is in the range of 0.10 [mΩ] - 0.59 [mΩ], for example, in the range of 0.30 [mΩ] - 0.50 [mΩ], for example, 0.45 [mΩ]. The total ON resistance of the protection FET circuit 344 of the battery pack 216 is in the range of 0.05 [mΩ] to 0.29 [mΩ], for example, in the range of 0.15 [mΩ] to 0.25 [mΩ], for example, 0.23 [mΩ].

[0171] (Configuration of Battery Pack 218) Battery pack 218 has a configuration that is almost identical to that of battery pack 216. The following mainly describes the differences between battery pack 218 and battery pack 216.

[0172] As shown in Figure 23, the battery pack 218 has battery cells 310, 312, 314, 316, 318, and 320 instead of battery cells 288, 290, 292, 294, 296, and 298. Battery cells 310, 312, and 314 are housed in insertion projections 254 of the upper casing 252. Battery cells 310, 312, and 314 are arranged so that their longitudinal direction is aligned with the vertical direction. Battery cells 312 and 314 are arranged side by side to the left and right behind battery cell 310. Battery cells 310, 312, and 314 are electrically connected in series to form a battery cell assembly 322. Battery cells 316, 318, and 320 are housed in the battery cell housing section 304 of the lower casing 302. The battery cells 316, 318, and 320 are arranged in a single row vertically and three rows horizontally, with their longitudinal direction aligned with the front-to-back direction. The battery cells 316, 318, and 320 are electrically connected in series to form a battery cell assembly 324. The battery cell assemblies 322 and 324 are electrically connected in parallel.

[0173] Battery cells 310, 312, 314, 316, 318, and 320 all have the same configuration as battery cell 100 of the battery pack 14 of Example 1. That is, battery cells 310, 312, 314, 316, 318, and 320 are tab-type battery cells. The shape of battery cells 310, 312, 314, 316, 318, and 320 is all of the 18650 type.

[0174] The weight of the battery pack 218 is in the range of 370 g - 500 g, for example, in the range of 400 g - 500 g, for example, 450 g, or in the range of 370 g - 500 g, for example, 450 g, or in the range of 500 g, for example, 480 g. In this case, the rated voltage of the battery pack 218 is in the range of 9.72 V - 11.88 V, for example, in the range of 10.26 V - 11.34 V, for example, 10.8 V. The rated capacity of the battery pack 218 is in the range of 4.0 [Ah] to 8.0 [Ah], for example, in the range of 4.0 [Ah] to 7.0 [Ah], for example, 6.0 [Ah], or in the range of 4.0 [Ah] to 12.0 [Ah], for example, 6.0 [Ah], or in the range of 10.0 [Ah], for example, 10.0 [Ah]. The energy capacity of the battery pack 218 is in the range of 38.9 [Wh] to 95.0 [Wh], for example, in the range of 43.2 [Wh] to 75.6 [Wh], for example, 64.8 [Wh], or in the range of 38.88 [Wh] to 142.56 [Wh], for example, 61.56 [Wh] to 113.40 [Wh], for example, 108 [Wh]. The continuous discharge output of the battery pack 218 is in the range of 180 [W] - 690 [W], for example, in the range of 210 [W] - 690 [W], for example, in the range of 350 [W] - 560 [W], for example, 470 [W]. The continuous discharge output per unit mass of the battery pack 218 is in the range of 0.4 [W / g] - 1.9 [W / g], for example, in the range of 0.4 [W / g] - 1.5 [W / g], for example, in the range of 0.7 [W / g] - 1.2 [W / g], for example, 1.0 [W / g], or in the range of 0.75 [W / g] - 1.8 [W / g], for example, in the range of 1.0 [W / g] - 1.6 [W / g], for example, 1.2 [W / g].

[0175] In the battery pack 218, the height H3 (see Figure 19) from the mounting surface of the positive power terminal 272 (or negative power terminal 274) (i.e., the upper surface of the cell holder 242) to the upper end of the positive power terminal 272 (or negative power terminal 274) is within the range of 3.0 [mm] - 15.0 [mm], for example, within the range of 8.6 [mm] - 15.0 [mm], for example, 10.0 [mm], or within the range of 3.0 [mm] - 15.0 [mm], for example, within the range of 3.0 [mm] - 8.5 [mm], for example, 8.0 [mm]. In the battery pack 218, the plate thickness of the positive power terminal 272 (or negative power terminal 274) is in the range of 0.30 [mm] - 0.64 [mm], for example, in the range of 0.30 [mm] - 0.59 [mm], for example, in the range of 0.40 [mm] - 0.55 [mm], for example, 0.50 [mm], or in the range of 0.30 [mm] - 1.00 [mm], for example, in the range of 0.30 [mm] - 0.64 [mm], for example, in the range of 0.30 [mm] - 0.59 [mm], for example, 0.45 [mm]. In the battery pack 218, the conductivity of the positive power terminal 272 (or negative power terminal 274) is in the range of 1 [%IACS] - 106 [%IACS], for example, in the range of 1 [%IACS] - 30 [%IACS], for example, 25 [%IACS].

[0176] In the battery pack 218, the lead plate 245 is joined to the positive cell terminal 122 or negative cell terminal 124 (see Figure 7) of the battery cells 310, 312, 314, 316, 318, and 320 by spot welding. In the battery pack 218, the thickness of the lead plate 245 is within the range of 0.10 [mm] - 1.00 [mm], for example, within the range of 0.10 [mm] - 0.30 [mm], for example, 0.20 [mm], or within the range of 0.10 [mm] - 0.19 [mm], within the range of 0.20 [mm] - 0.29 [mm], within the range of 0.30 [mm] - 0.39 [mm], within the range of 0.40 [mm] - 0.49 [mm], within the range of 0.50 [mm] - 0.59 [mm], within the range of 0.60 [mm] - 0.69 [mm], within the range of 0.70 [mm] - 0.79 [mm], within the range of 0.80 [mm] - 0.89 [mm], or within the range of 0.90 [mm] - 1.00 [mm]. In the battery pack 218, the conductivity of the lead plate 245 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 1 [%IACS] to 30 [%IACS], for example, 25 [%IACS].

[0177] In this embodiment, the battery pack 218 houses the battery cells 310, 312, and 314 in insertion protrusions 254 that correspond to the insertion recesses 222 (see Figure 18) of the electrical device 210. Therefore, the shape of the battery cells 310, 312, and 314 must be of the 18650 type, which fits inside the insertion protrusions 254, and cannot be of the 21700 type. In contrast, the battery cells 316, 318, and 320 are housed in a battery cell housing section 304 that is located outside the insertion recesses 222 when the battery pack 218 is attached to the electrical device 210. Therefore, the shape of the battery cells 316, 318, and 320 may be of the 18650 type or the 21700 type. The shape and number of battery cells 316, 318, and 320 housed in the battery cell housing section 304 can be varied.

[0178] As shown in Figure 48, the battery pack 218, like the battery pack 216, further includes a fuse link 330, a cell temperature detection circuit 332, a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. Note that the battery pack 218 does not necessarily have a fuse link 330. Also, the battery pack 218 does not necessarily have a circuit board 244. Therefore, the battery pack 214 does not necessarily have a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. In this case, the cell temperature detection circuit 332 and the positive cell terminals 122 and / or negative cell terminals 124 (see Figure 7) of each battery cell 310, 312, 314, 316, 318, 320 may be directly connected to the signal communication terminals 276, 278, 280.

[0179] The total number of pins in the MCU340 of the battery pack 218 is in the range of 6 to 32, for example, in the range of 16 to 32, for example, 32. The ROM capacity of the MCU340 of the battery pack 218 is in the range of 8 [kByte] to 63 [kByte], for example, in the range of 16 [kByte] to 32 [kByte], for example, 32 [kByte]. The RAM capacity of the MCU340 of the battery pack 218 is in the range of 1 [kByte] to 4 [kByte], for example, in the range of 2 [kByte] to 4 [kByte], for example, 4 [kByte]. The CPU clock frequency of the MCU 340 of the battery pack 218 is in the range of 4.8 [MHz] to 19.2 [MHz], for example, in the range of 14.4 [MHz] to 17.6 [MHz], for example, 16.0 [MHz]. The number of parallel FETs in the protection FET circuit 344 of the battery pack 218 is in the range of 0 to 3, for example, in the range of 0 to 2, for example, in the range of 1 to 2, for example, 1. The ON resistance of each FET in the protection FET circuit 344 of the battery pack 218 is in the range of 0.60 [mΩ] to 5.00 [mΩ], for example, in the range of 0.60 [mΩ] to 1.00 [mΩ], for example, 0.65 [mΩ]. The total ON resistance of the protection FET circuit 344 of the battery pack 218 is in the range of 0.30 [mΩ] to 5.00 [mΩ], for example, in the range of 0.30 [mΩ] to 0.50 [mΩ], for example, 0.33 [mΩ].

[0180] The features of the battery packs 212, 214, 216, and 218 of this embodiment are summarized in Tables 5 and 6 below.

[0181]

[0182]

[0183] (Example 3) As shown in Figure 26, the electrical equipment system 402 of this embodiment comprises an electrical device 404 and battery packs 406, 408, 410, and 412. One of the battery packs 406, 408, 410, and 412 can be selectively attached to the electrical device 404. The electrical device 404 is an electrical device that operates using power supplied from the battery packs 406, 408, 410, and 412. The electrical device 404 may be, for example, a power tool that uses a motor as a power source, such as a driver drill or an impact driver, or a motor-powered work machine that uses a motor as a power source, such as a hedge trimmer or a hand saw. Alternatively, the electrical device 404 may be an electrical device that does not have a motor, such as a light, radio, or speaker. Alternatively, the electrical device 404 may be a charger that charges the battery packs 406, 408, 410, and 412.

[0184] (Configuration of electrical device 404) As shown in Figures 27 and 28, electrical device 404 is equipped with a battery pack mounting section 20, similar to electrical device 10 in Embodiment 1. Battery packs 406, 408, 410, and 412 can be attached to the battery pack mounting section 20 by sliding them in a predetermined sliding direction relative to the battery pack mounting section 20. That is, battery packs 406, 408, 410, and 412 are slide-type battery packs. Hereinafter, the direction in which battery packs 406, 408, 410, and 412 are slid when attaching them to the battery pack mounting section 20 will be referred to as the rear direction, and the direction in which battery packs 406, 408, 410, and 412 are slid when removing them from the battery pack mounting section 20 will be referred to as the front direction. Furthermore, with the battery packs 406, 408, 410, and 412 attached to the battery pack mounting section 20, the direction in which the battery pack mounting section 20 is located relative to the battery packs 406, 408, 410, and 412 is referred to as the upward direction, and the opposite direction to the upward direction is referred to as the downward direction. In addition, the direction perpendicular to the front-back direction and the up-down direction is referred to as the left-right direction.

[0185] (Configuration of Battery Pack 406) As shown in Figure 29, the battery pack 406 comprises battery cells 414 and 416, a cell holder 418, a circuit board 420, a lead plate 422, battery-side terminals 424, and a casing 426. The battery cells 414 and 416 are arranged in a row, one vertically and two horizontally, with their longitudinal direction aligned with the front-to-back direction. The battery cells 414 and 416 are electrically connected in series via the lead plate 422. The cell holder 418 holds the battery cells 414 and 416. The circuit board 420 is held by the cell holder 418 above it and is electrically connected to the battery cells 414 and 416 via the lead plate 422. The battery-side terminals 424 are provided on the circuit board 420. The casing 426 houses the battery cells 414, 416, the cell holder 418, the circuit board 420, the lead plate 422, and the battery-side terminals 424.

[0186] As shown in Figure 30, the casing 426 comprises a lower casing 428 and an upper casing 430. The upper casing 430 has a terminal opening 432 and a battery-side rail 434. The terminal opening 432 is positioned to correspond to the device-side terminals 22 of the electrical device 404 (see Figure 27). The terminal opening 432 has a shape that allows the device-side terminals 22 to pass through when the battery pack 406 is attached to the electrical device 404. The battery-side rail 434 comprises a right-side rail 436 extending in the front-rear direction to the right of the terminal opening 432 and a left-side rail 438 extending in the front-rear direction to the left of the terminal opening 432. The right-side rail 436 and the left-side rail 438 engage with the right-side rail 34 and the left-side rail 36 of the electrical device 404 (see Figure 27) so as to be movable in the front-rear direction when the battery pack 406 is attached to the electrical device 404.

[0187] A hook 440 is attached to the upper casing 430. The hook 440 has an engaging portion 442 and an operating portion 444. The hook 440 is biased upward by a compression spring 446. When the battery pack 406 is attached to the electrical device 404, the engaging portion 442 of the hook 440 fits into the engaging groove 26 (see Figure 27) of the electrical device 404, thereby fixing the battery pack 406 to the electrical device 404. From this state, when the user pushes down the operating portion 444 of the hook 440, the engaging portion 442 disengages from the engaging groove 26. In this state, the user can slide the battery pack 406 forward relative to the electrical device 404 and remove the battery pack 406 from the electrical device 404.

[0188] Battery cells 414 and 416 both have the same configuration as battery cell 40 in Example 1. That is, battery cells 414 and 416 are tablet-type battery cells.

[0189] As shown in Figure 31, the battery-side terminal 424 includes a positive power terminal 448 and a negative power terminal 450 for charging or discharging power between the electrical device 404 and the battery pack 406, and a signal communication terminal 452 for signal communication between the electrical device 404 and the battery pack 406. The positive power terminal 448 and the negative power terminal 450 are positioned to correspond to the positive power terminal 28 and the negative power terminal 30 (see Figure 27) of the electrical device 404. The signal communication terminal 452 is positioned to correspond to the signal communication terminal 32 of the electrical device 404. When the battery pack 406 is attached to the electrical device 404, the positive power terminal 448 and the negative power terminal 450 mechanically engage with and electrically connect to the positive power terminal 28 and the negative power terminal 30 of the electrical device 404 by clamping them from the left and right directions, respectively. When the battery pack 406 is attached to the electrical device 404, the signal communication terminal 452 mechanically engages with and electrically connects with the corresponding signal communication terminal 32 of the electrical device 404 by clamping it from the left and right directions.

[0190] The length from the front end to the rear end of the positive power terminal 448 is the same as the length from the front end to the rear end of the negative power terminal 450. The width from the right end to the left end of the positive power terminal 448 is the same as the width from the right end to the left end of the negative power terminal 450. The height from the mounting surface of the positive power terminal 448 (i.e., the top surface of the circuit board 420) to the top end of the positive power terminal 448 is the same as the height from the mounting surface of the negative power terminal 450 (i.e., the top surface of the circuit board 420) to the top end of the negative power terminal 450.

[0191] The plate thickness of the positive power terminal 448 (or negative power terminal 450) is in the range of 0.46 [mm] - 1.00 [mm], for example, in the range of 0.60 [mm] - 0.80 [mm], for example, in the range of 0.60 [mm] - 0.70 [mm], for example, 0.60 [mm]. The conductivity of the positive power terminal 448 (or negative power terminal 450) is in the range of 1 [%IACS] - 106 [%IACS], for example, in the range of 31 [%IACS] - 106 [%IACS], for example, 40 [%IACS]. The plate thickness of the signal communication terminal 452 is in the range of 0.30 [mm] - 0.59 [mm], for example, in the range of 0.30 [mm] - 0.45 [mm], for example, in the range of 0.35 [mm] - 0.45 [mm], for example, 0.40 [mm]. The conductivity of the signal communication terminal 452 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 1 [%IACS] to 30 [%IACS], for example, 25 [%IACS].

[0192] If the shape of the battery cells 414 and 416 is of the 18650 type, the length L9 from the front end to the rear end of the positive power terminal 448 (or negative power terminal 450) is in the range of 4.0 [mm] to 22.0 [mm], for example, in the range of 10.6 [mm] to 19.6 [mm], for example, 17.1 [mm]. The length L10 from the front end to the rear end of the casing 426 is in the range of 83.0 [mm] to 92.0 [mm], for example, in the range of 84.9 [mm] to 89.4 [mm], for example, 86.7 [mm]. The ratio of the length L9 of the positive power terminal 448 (or negative power terminal 450) from its front end to its rear end to the length L10 of the casing 426 from its front end to its rear end is in the range of 4.3 [%] - 23.9 [%], for example, in the range of 11.9 [%] - 23.1 [%], for example, 19.7 [%]. The width W9 of the positive power terminal 448 (or negative power terminal 450) from its right end to its left end is in the range of 3 [mm] - 6 [mm], for example, in the range of 3.9 [mm] - 5.4 [mm], for example, 4.7 [mm]. The width W10 of the casing 426 from its right end to its left end is in the range of 40.5 [mm] - 46.5 [mm], for example, in the range of 42.0 [mm] - 45.0 [mm], for example, 43.5 [mm]. The ratio of the width W9 of the positive power terminal 448 (or negative power terminal 450) from right end to left end to the width W10 of the casing 426 from right end to left end is in the range of 6.5 [%] - 14.8 [%], for example, in the range of 8.7 [%] - 12.9 [%], for example, 10.8 [%]. The height H11 (see Figure 29) from the mounting surface of the positive power terminal 448 (or negative power terminal 450) (i.e., the top surface of the circuit board 420) to the upper end of the positive power terminal 448 (or negative power terminal 450) is in the range of 7.0 [mm] - 14.0 [mm], for example, in the range of 8.9 [mm] - 12.4 [mm], for example, 10.7 [mm]. The height H11 (see Figure 29) from the mounting surface of the signal communication terminal 452 (i.e., the top surface of the circuit board 420) to the upper end of the signal communication terminal 452 is in the range of 7.0 [mm] - 14.0 [mm], for example, in the range of 8.9 [mm] - 12.4 [mm], for example, 10.7 [mm].

[0193] If the shape of the battery cells 414 and 416 is of type 21700, the length L9 from the front end to the rear end of the positive power terminal 448 (or negative power terminal 450) is in the range of 4.0 [mm] to 22.0 [mm], for example, in the range of 10.6 [mm] to 19.6 [mm], for example, 17.1 [mm]. The length L10 from the front end to the rear end of the casing 426 is in the range of 87.0 [mm] to 96.0 [mm], for example, in the range of 89.1 [mm] to 93.6 [mm], for example, 91.1 [mm]. The ratio of the length L9 of the positive power terminal 448 (or negative power terminal 450) from its front end to its rear end to the length L10 of the casing 426 from its front end to its rear end is within the range of 4.2 [%] - 22.9 [%], for example, within the range of 11.3 [%] - 22.0 [%], for example, 18.8 [%]. The width W9 of the positive power terminal 448 (or negative power terminal 450) from its right end to its left end is within the range of 3.0 [mm] - 6.0 [mm], for example, within the range of 3.9 [mm] - 5.4 [mm], for example, 4.7 [mm]. The width W10 of the casing 426 from its right end to its left end is within the range of 46.5 [mm] - 56.5 [mm], for example, within the range of 50.1 [mm] - 55.1 [mm], for example, 53.6 [mm]. The ratio of the width W9 of the positive power terminal 448 (or negative power terminal 450) from right end to left end to the width W10 of the casing 426 from right end to left end is in the range of 5.3 [%] - 12.9 [%], for example, in the range of 7.1 [%] - 10.8 [%], for example, 8.8 [%]. The height H11 (see Figure 29) from the mounting surface of the positive power terminal 448 (or negative power terminal 450) (i.e., the top surface of the circuit board 420) to the upper end of the positive power terminal 448 (or negative power terminal 450) is in the range of 7.0 [mm] - 14.0 [mm], for example, in the range of 8.9 [mm] - 12.4 [mm], for example, 10.7 [mm]. The height H11 (see Figure 29) from the mounting surface of the signal communication terminal 452 (i.e., the top surface of the circuit board 420) to the upper end of the signal communication terminal 452 is in the range of 7.0 [mm] - 14.0 [mm], for example, in the range of 8.9 [mm] - 12.4 [mm], for example, 10.7 [mm].

[0194] The lead plate 422 is joined to the positive cell terminal 90 or negative cell terminal 92 (see Figure 7) of the battery cells 414 and 416 by laser welding or spot welding. The thickness of the lead plate 422 is within the range of 0.10 [mm] - 1.00 [mm], for example, within the range of 0.31 [mm] - 1.00 [mm], for example, 0.50 [mm], or within the range of 0.10 [mm] - 0.19 [mm], within the range of 0.20 [mm] - 0.29 [mm], within the range of 0.30 [mm] - 0.39 [mm], within the range of 0.40 [mm] - 0.49 [mm], within the range of 0.50 [mm] - 0.59 [mm], within the range of 0.60 [mm] - 0.69 [mm], within the range of 0.70 [mm] - 0.79 [mm], within the range of 0.80 [mm] - 0.89 [mm], or within the range of 0.90 [mm] - 1.00 [mm]. The conductivity of the lead plate 422 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 31 [%IACS] to 106 [%IACS], for example, 40 [%IACS].

[0195] If the shape of the battery cells 414 and 416 is of the 18650 type, the weight of the battery pack 406 is in the range of 120 [g] - 200 [g], for example, in the range of 140 [g] - 180 [g], for example, 160 [g]. In this case, the rated voltage of the battery pack 406 is in the range of 6.48 [V] - 7.92 [V], for example, in the range of 6.84 [V] - 7.56 [V], for example, 7.2 [V]. The rated capacity of the battery pack 406 is in the range of 2.0 [Ah] - 4.0 [Ah], for example, in the range of 2.0 [Ah] - 3.5 [Ah], for example, 3.0 [Ah]. The energy capacity of the battery pack 406 is in the range of 13.0 [Wh] - 31.7 [Wh], for example, in the range of 14.4 [Wh] - 25.2 [Wh], for example, 21.6 [Wh]. The continuous discharge output of the battery pack 406 is in the range of 230 [W] - 540 [W], for example, in the range of 230 [W] - 510 [W], for example, in the range of 270 [W] - 390 [W], for example, 300 [W]. The continuous discharge output per unit mass of the battery pack 406 is in the range of 1.2 [W / g] - 4.5 [W / g], for example, in the range of 1.4 [W / g] - 3.3 [W / g], for example, in the range of 1.6 [W / g] - 2.4 [W / g], for example, 1.8 [W / g].

[0196] If the shape of the battery cells 414 and 416 is of type 21700, the weight of the battery pack 406 is in the range of 190 [g] - 290 [g], for example, in the range of 210 [g] - 270 [g], for example, 240 [g]. In this case, the rated voltage of the battery pack 406 is in the range of 6.48 [V] - 7.92 [V], for example, in the range of 6.84 [V] - 7.56 [V], for example, 7.2 [V]. The rated capacity of the battery pack 406 is in the range of 3.0 [Ah] - 6.0 [Ah], for example, in the range of 3.0 [Ah] - 5.5 [Ah], for example, 5.0 [Ah]. The energy capacity of the battery pack 406 is in the range of 19.4 [Wh] - 47.5 [Wh], for example, in the range of 21.6 [Wh] - 39.6 [Wh], for example, 36.0 [Wh]. The continuous discharge output of the battery pack 406 is in the range of 300 [W] - 780 [W], for example, in the range of 300 [W] - 730 [W], for example, in the range of 360 [W] - 550 [W], for example, 410 [W]. The continuous discharge output per unit mass of the battery pack 406 is in the range of 1.0 [W / g] - 4.1 [W / g], for example, in the range of 1.2 [W / g] - 3.2 [W / g], for example, in the range of 1.5 [W / g] - 2.2 [W / g], for example, 1.7 [W / g].

[0197] Figure 49 shows an example of the circuit configuration of the battery pack 406 and the electrical device 404. Similar to the battery pack 12 of Embodiment 1, the battery pack 406 further includes a fuse link 330, a cell temperature detection circuit 332, a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. The power supply circuit 334, the current detection circuit 336, the AFE 338, the MCU 340, the voltage detection circuit 342, the protection FET circuit 344, the FET temperature detection circuit 346, the charger detection circuit 348, and the input / output control circuit 350 are provided on the circuit board 420.

[0198] The electrical device 404, like the electrical device 10 in Embodiment 1, includes a power supply circuit 352, an MCU 354, an LED 356, a trigger switch 358, a motor control circuit 360, a motor drive circuit 362, an electric motor 364, a protection FET circuit 366, and an FET control circuit 368.

[0199] The total number of pins in the MCU340 of the battery pack 406 is in the range of 33-100, for example, in the range of 33-60, for example, 48. The ROM capacity of the MCU340 of the battery pack 406 is in the range of 64 [kByte]-1024 [kByte], for example, in the range of 64 [kByte]-256 [kByte], for example, 128 [kByte]. The RAM capacity of the MCU340 of the battery pack 406 is in the range of 5 [kByte]-32 [kByte], for example, in the range of 6 [kByte]-16 [kByte], for example, 7 [kByte]. The CPU clock frequency of the MCU 340 of the battery pack 406 is in the range of 19.3 [MHz] - 128.0 [MHz], for example, in the range of 25.6 [MHz] - 48.0 [MHz], for example, 32.0 [MHz]. The number of parallel FETs in the protection FET circuit 344 of the battery pack 406 is in the range of 0 - 4, for example, in the range of 1 - 4, for example, in the range of 2 - 3, for example, 2. The ON resistance of each FET in the protection FET circuit 344 of the battery pack 406 is in the range of 0.10 [mΩ] - 0.59 [mΩ], for example, in the range of 0.30 [mΩ] - 0.50 [mΩ], for example, 0.45 [mΩ]. The total ON resistance of the protection FET circuit 344 of the battery pack 406 is in the range of 0.05 [mΩ] - 0.29 [mΩ], for example, in the range of 0.15 [mΩ] - 0.25 [mΩ], for example, 0.23 [mΩ].

[0200] (Configuration of Battery Pack 408) Battery pack 408 has a configuration that is almost identical to that of battery pack 406. The following mainly describes the differences between battery pack 408 and battery pack 406.

[0201] As shown in Figure 29, the battery pack 408 is equipped with battery cells 454 and 456 instead of battery cells 414 and 416. The battery cells 454 and 456 are arranged in a single row vertically and two rows horizontally, with their longitudinal direction aligned with the front-to-back direction. The battery cells 454 and 456 are electrically connected in series via lead plates 422.

[0202] Battery cells 454 and 456 both have the same configuration as battery cell 100 in Example 1. That is, battery cells 454 and 456 are tab-type battery cells.

[0203] If the shape of the battery cells 454 and 456 is of the 18650 type, the weight of the battery pack 408 is in the range of 120 [g] - 200 [g], for example, in the range of 140 [g] - 180 [g], for example, 160 [g]. In this case, the rated voltage of the battery pack 408 is in the range of 6.48 [V] - 7.92 [V], for example, in the range of 6.84 [V] - 7.56 [V], for example, 7.2 [V]. The rated capacity of the battery pack 408 is in the range of 2.0 [Ah] - 4.0 [Ah], for example, in the range of 2.0 [Ah] - 3.5 [Ah], for example, 3.0 [Ah]. The energy capacity of the battery pack 408 is in the range of 13.0 [Wh] - 31.7 [Wh], for example, in the range of 14.4 [Wh] - 25.2 [Wh], for example, 21.6 [Wh]. The continuous discharge output of the battery pack 408 is in the range of 60 [W] - 230 [W], for example, in the range of 70 [W] - 230 [W], for example, in the range of 120 [W] - 190 [W], for example, 160 [W]. The continuous discharge output per unit mass of the battery pack 408 is in the range of 0.3 [W / g] - 1.9 [W / g], for example, in the range of 0.3 [W / g] - 1.4 [W / g], for example, in the range of 0.7 [W / g] - 1.1 [W / g], for example, 1.0 [W / g].

[0204] If the shape of the battery cells 454 and 456 is of type 21700, the weight of the battery pack 408 is in the range of 190 [g] - 290 [g], for example, in the range of 210 [g] - 270 [g], for example, 240 [g]. In this case, the rated voltage of the battery pack 408 is in the range of 6.48 [V] - 7.92 [V], for example, in the range of 6.84 [V] - 7.56 [V], for example, 7.2 [V]. The rated capacity of the battery pack 408 is in the range of 3.0 [Ah] - 6.0 [Ah], for example, in the range of 3.0 [Ah] - 5.5 [Ah], for example, 5.0 [Ah]. The energy capacity of the battery pack 408 is in the range of 19.4 [Wh] - 47.5 [Wh], for example, in the range of 21.6 [Wh] - 39.6 [Wh], for example, 36.0 [Wh]. The continuous discharge output of the battery pack 408 is in the range of 60 [W] - 300 [W], for example, in the range of 70 [W] - 300 [W], for example, in the range of 130 [W] - 240 [W], for example, 200 [W]. The continuous discharge output per unit mass of the battery pack 408 is in the range of 0.2 [W / g] - 1.6 [W / g], for example, in the range of 0.2 [W / g] - 1.2 [W / g], for example, in the range of 0.5 [W / g] - 1.0 [W / g], for example, 0.8 [W / g].

[0205] In the battery pack 408, the height H11 (see Figure 29) from the mounting surface of the positive power terminal 448 (or negative power terminal 450) (i.e., the upper surface of the circuit board 420) to the upper end of the positive power terminal 448 (or negative power terminal 450) is in the range of 7.0 [mm] - 14.0 [mm], for example, in the range of 8.9 [mm] - 12.4 [mm], for example, 10.7 [mm]. In the battery pack 408, the plate thickness of the positive power terminal 448 (or negative power terminal 450) is in the range of 0.30 [mm] - 0.59 [mm], for example, in the range of 0.30 [mm] - 0.45 [mm], for example, in the range of 0.35 [mm] - 0.45 [mm], for example, 0.40 [mm]. In the battery pack 408, the conductivity of the positive power terminal 448 (or negative power terminal 450) is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 1 [%IACS] to 30 [%IACS], for example, 25 [%IACS].

[0206] In the battery pack 408, the lead plate 422 is joined to the positive cell terminal 122 or negative cell terminal 124 (see Figure 7) of the battery cells 454 and 456 by spot welding. In the battery pack 408, the thickness of the lead plate 422 is within the range of 0.10 [mm] - 1.00 [mm], for example, within the range of 0.10 [mm] - 0.30 [mm], for example, 0.20 [mm], or within the range of 0.10 [mm] - 0.19 [mm], within the range of 0.20 [mm] - 0.29 [mm], within the range of 0.30 [mm] - 0.39 [mm], within the range of 0.40 [mm] - 0.49 [mm], within the range of 0.50 [mm] - 0.59 [mm], within the range of 0.60 [mm] - 0.69 [mm], within the range of 0.70 [mm] - 0.79 [mm], within the range of 0.80 [mm] - 0.89 [mm], or within the range of 0.90 [mm] - 1.00 [mm]. In the battery pack 408, the conductivity of the lead plate 422 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 1 [%IACS] to 30 [%IACS], for example, 25 [%IACS].

[0207] As shown in Figure 49, the battery pack 408, like the battery pack 406, further includes a fuse link 330, a cell temperature detection circuit 332, a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. Note that the battery pack 408 does not necessarily have a fuse link 330. Also, the battery pack 408 does not necessarily have a circuit board 420. Therefore, the battery pack 408 does not necessarily have a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. In this case, the cell temperature detection circuit 332 and the positive cell terminals 122 and / or negative cell terminals 124 of each battery cell 454, 456 (see Figure 7) may be directly connected to the signal communication terminal 452.

[0208] The total number of pins in the MCU340 of the battery pack 408 is in the range of 6-32, for example, in the range of 16-32, for example, 32. The ROM capacity of the MCU340 of the battery pack 408 is in the range of 8 [kByte]-63 [kByte], for example, in the range of 16 [kByte]-32 [kByte], for example, 32 [kByte]. The RAM capacity of the MCU340 of the battery pack 408 is in the range of 1 [kByte]-4 [kByte], for example, in the range of 2 [kByte]-4 [kByte], for example, 4 [kByte]. The CPU clock frequency of the MCU 340 of the battery pack 408 is in the range of 4.8 [MHz] to 19.2 [MHz], for example, in the range of 14.4 [MHz] to 17.6 [MHz], for example, 16.0 [MHz]. The number of parallel FETs in the protection FET circuit 344 of the battery pack 408 is in the range of 0 to 3, for example, in the range of 0 to 2, for example, in the range of 1 to 2, for example, 1. The ON resistance of each FET in the protection FET circuit 344 of the battery pack 408 is in the range of 0.60 [mΩ] to 5.00 [mΩ], for example, in the range of 0.60 [mΩ] to 1.00 [mΩ], for example, 0.65 [mΩ]. The total ON resistance of the protection FET circuit 344 of the battery pack 408 is in the range of 0.30 [mΩ] to 5.00 [mΩ], for example, in the range of 0.30 [mΩ] to 0.50 [mΩ], for example, 0.33 [mΩ].

[0209] (Configuration of Battery Pack 410) As shown in Figure 32, the battery pack 410 comprises battery cells 458, 460, 462, and 464, a cell holder 466, a circuit board 468, a lead plate 470, battery-side terminals 472, and a casing 474. The battery cells 458, 460, 462, and 464 are arranged in two rows vertically and two columns horizontally, with their longitudinal direction aligned with the front-to-back direction. Battery cells 458 and 460 are electrically connected in parallel via the lead plate 470 to form a battery cell pair 476. Battery cells 462 and 464 are electrically connected in parallel via the lead plate 470 to form a battery cell pair 478. Battery cell pairs 476 and 478 are electrically connected in series via the lead plate 470. The cell holder 466 holds the battery cells 458, 460, 462, and 464. The circuit board 468 is held by the cell holder 466 above it and is electrically connected to the battery cells 458, 460, 462, and 464 via the lead plate 470. The battery-side terminals 472 are provided on the circuit board 468. The casing 474 houses the battery cells 458, 460, 462, and 464, the cell holder 466, the circuit board 468, the lead plate 470, and the battery-side terminals 472.

[0210] As shown in Figure 33, the casing 474 comprises a lower casing 480 and an upper casing 482. The upper casing 482 has terminal openings 432 and battery-side rails 434, similar to the battery packs 406 and 408.

[0211] A hook 484 is attached to the upper casing 482. The hook 484 has an engaging portion 486 and an operating portion 488. As shown in Figure 32, the hook 484 is biased upward by a compression spring 490. When the battery pack 410 is attached to the electrical device 404, the engaging portion 486 of the hook 484 fits into the engaging groove 26 (see Figure 28) of the electrical device 404, thereby fixing the battery pack 410 to the electrical device 404. From this state, when the user pushes down the operating portion 488 of the hook 484, the engaging portion 486 disengages from the engaging groove 26. In this state, the user can slide the battery pack 410 forward relative to the electrical device 404 and remove the battery pack 410 from the electrical device 404.

[0212] Battery cells 458, 460, 462, and 464 all have the same configuration as battery cell 40 in Example 1. That is, battery cells 458, 460, 462, and 464 are tablet-type battery cells.

[0213] As shown in Figure 34, the battery-side terminal 472 includes a positive power terminal 492 and a negative power terminal 494 for charging or discharging power between the electrical device 404 and the battery pack 410, and a signal communication terminal 496 for signal communication between the electrical device 404 and the battery pack 410. The positive power terminal 492 and the negative power terminal 494 are positioned to correspond to the positive power terminal 28 and the negative power terminal 30 (see Figure 28) of the electrical device 404. The signal communication terminal 496 is positioned to correspond to the signal communication terminal 32 of the electrical device 404. When the battery pack 410 is attached to the electrical device 404, the positive power terminal 492 and the negative power terminal 494 mechanically engage with and electrically connect to the positive power terminal 28 and the negative power terminal 30 of the electrical device 404 by clamping them from the left and right directions, respectively. When the battery pack 410 is attached to the electrical device 404, the signal communication terminal 496 mechanically engages with and electrically connects with the corresponding signal communication terminal 32 of the electrical device 404 by clamping it from the left and right directions.

[0214] The length from the front end to the rear end of the positive power terminal 492 is the same as the length from the front end to the rear end of the negative power terminal 494. The width from the right end to the left end of the positive power terminal 492 is the same as the width from the right end to the left end of the negative power terminal 494. The height from the mounting surface of the positive power terminal 492 (i.e., the top surface of the circuit board 468) to the top end of the positive power terminal 492 is the same as the height from the mounting surface of the negative power terminal 494 (i.e., the top surface of the circuit board 468) to the top end of the negative power terminal 494.

[0215] The plate thickness of the positive power terminal 492 (or negative power terminal 494) is in the range of 0.46 [mm] - 1.00 [mm], for example, in the range of 0.60 [mm] - 0.80 [mm], for example, in the range of 0.60 [mm] - 0.70 [mm], for example, 0.60 [mm]. The conductivity of the positive power terminal 492 (or negative power terminal 494) is in the range of 1 [%IACS] - 106 [%IACS], for example, in the range of 31 [%IACS] - 106 [%IACS], for example, 40 [%IACS]. The plate thickness of the signal communication terminal 496 is in the range of 0.30 [mm] - 0.59 [mm], for example, in the range of 0.30 [mm] - 0.45 [mm], for example, in the range of 0.35 [mm] - 0.45 [mm], for example, 0.40 [mm]. The conductivity of the signal communication terminal 496 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 1 [%IACS] to 30 [%IACS], for example, 25 [%IACS].

[0216] If the shape of the battery cells 458, 460, 462, and 464 is of the 18650 type, the length L11 from the front end to the rear end of the positive power terminal 492 (or negative power terminal 494) is in the range of 4.0 [mm] to 22.0 [mm], for example, in the range of 10.6 [mm] to 19.6 [mm], for example, 17.1 [mm]. The length L12 from the front end to the rear end of the casing 474 is in the range of 83.0 [mm] to 92.0 [mm], for example, in the range of 84.9 [mm] to 89.4 [mm], for example, 86.7 [mm]. The ratio of the length L11 of the positive power terminal 492 (or negative power terminal 494) from front to rear to the length L12 of the casing 474 from front to rear is in the range of 4.3 [%] - 23.9 [%], for example, in the range of 11.9 [%] - 23.1 [%], for example, 19.7 [%]. The width W11 of the positive power terminal 492 (or negative power terminal 494) from right to left is in the range of 3.0 [mm] - 6.0 [mm], for example, in the range of 3.9 [mm] - 5.4 [mm], for example, 4.7 [mm]. The width W12 of the casing 474 from right to left is in the range of 40.5 [mm] - 46.5 [mm], for example, in the range of 42.0 [mm] - 45.0 [mm], for example, 43.5 [mm]. The ratio of the width W11 of the positive power terminal 492 (or negative power terminal 494) from right end to left end to the width W12 of the casing 474 from right end to left end is in the range of 6.5 [%] - 14.8 [%], for example, in the range of 8.7 [%] - 12.9 [%], for example, 10.8 [%]. The height H12 (see Figure 32) from the mounting surface of the positive power terminal 492 (or negative power terminal 494) (i.e., the top surface of the circuit board 468) to the top end of the positive power terminal 492 (or negative power terminal 494) is in the range of 7.0 [mm] - 14.0 [mm], for example, in the range of 8.9 [mm] - 12.4 [mm], for example, 10.7 [mm]. The height H12 (see Figure 32) from the mounting surface of the signal communication terminal 496 (i.e., the top surface of the circuit board 468) to the upper end of the signal communication terminal 496 is in the range of 7.0 [mm] - 14.0 [mm], for example, in the range of 8.9 [mm] - 12.4 [mm], for example, 10.7 [mm].

[0217] If the shape of the battery cells 458, 460, 462, and 464 is of type 21700, the length L11 from the front end to the rear end of the positive power terminal 492 (or negative power terminal 494) is in the range of 4.0 [mm] to 22.0 [mm], for example, in the range of 10.6 [mm] to 19.6 [mm], for example, 17.1 [mm]. The length L12 from the front end to the rear end of the casing 474 is in the range of 87.0 [mm] to 96.0 [mm], for example, in the range of 89.1 [mm] to 93.6 [mm], for example, 91.1 [mm]. The ratio of the length L11 of the positive power terminal 492 (or negative power terminal 494) from its front end to its rear end to the length L12 of the casing 474 from its front end to its rear end is in the range of 4.2 [%] - 22.9 [%], for example, in the range of 11.3 [%] - 22.0 [%], for example, 18.8 [%]. The width W11 of the positive power terminal 492 (or negative power terminal 494) from its right end to its left end is in the range of 3.0 [mm] - 6.0 [mm], for example, in the range of 3.9 [mm] - 5.4 [mm], for example, 4.7 [mm]. The width W12 of the casing 474 from its right end to its left end is in the range of 46.5 [mm] - 56.5 [mm], for example, in the range of 50.1 [mm] - 55.1 [mm], for example, 53.6 [mm]. The ratio of the width W11 of the positive power terminal 492 (or negative power terminal 494) from right end to left end to the width W12 of the casing 474 from right end to left end is in the range of 5.3 [%] - 12.9 [%], for example, in the range of 7.1 [%] - 10.8 [%], for example, 8.8 [%]. The height H12 (see Figure 32) from the mounting surface of the positive power terminal 492 (or negative power terminal 494) (i.e., the top surface of the circuit board 468) to the upper end of the positive power terminal 492 (or negative power terminal 494) is in the range of 7.0 [mm] - 14.0 [mm], for example, in the range of 8.9 [mm] - 12.4 [mm], for example, 10.7 [mm]. The height H12 (see Figure 32) from the mounting surface of the signal communication terminal 496 (i.e., the top surface of the circuit board 468) to the upper end of the signal communication terminal 496 is in the range of 7.0 [mm] - 14.0 [mm], for example, in the range of 8.9 [mm] - 12.4 [mm], for example, 10.7 [mm].

[0218] The lead plate 470 is joined to the positive cell terminal 90 or negative cell terminal 92 (see Figure 7) of the battery cells 458, 460, 462, and 464 by laser welding or spot welding. The thickness of the lead plate 470 is within the range of 0.10 [mm] - 1.00 [mm], for example, within the range of 0.31 [mm] - 1.00 [mm], for example, 0.50 [mm], or within the range of 0.10 [mm] - 0.19 [mm], within the range of 0.20 [mm] - 0.29 [mm], within the range of 0.30 [mm] - 0.39 [mm], within the range of 0.40 [mm] - 0.49 [mm], within the range of 0.50 [mm] - 0.59 [mm], within the range of 0.60 [mm] - 0.69 [mm], within the range of 0.70 [mm] - 0.79 [mm], within the range of 0.80 [mm] - 0.89 [mm], or within the range of 0.90 [mm] - 1.00 [mm]. The conductivity of the lead plate 470 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 31 [%IACS] to 106 [%IACS], for example, 40 [%IACS].

[0219] If the shape of battery cells 458, 460, 462, and 464 is of the 18650 type, the weight of the battery pack 410 is in the range of 220 [g] - 340 [g], for example, in the range of 250 [g] - 310 [g], for example, 280 [g]. In this case, the rated voltage of the battery pack 410 is in the range of 6.48 [V] - 7.92 [V], for example, in the range of 6.84 [V] - 7.56 [V], for example, 7.2 [V]. The rated capacity of the battery pack 410 is in the range of 4.0 [Ah] - 8.0 [Ah], for example, in the range of 4.0 [Ah] - 7.0 [Ah], for example, 6.0 [Ah]. The energy capacity of the battery pack 410 is in the range of 25.9 [Wh] - 63.4 [Wh], for example, in the range of 28.8 [Wh] - 50.4 [Wh], for example, 43.2 [Wh]. The continuous discharge output of the battery pack 410 is in the range of 460 [W] - 1070 [W], for example, in the range of 460 [W] - 1020 [W], for example, in the range of 540 [W] - 790 [W], for example, 600 [W]. The continuous discharge output per unit mass of the battery pack 410 is in the range of 1.4 [W / g] - 4.9 [W / g], for example, in the range of 1.6 [W / g] - 3.8 [W / g], for example, in the range of 1.9 [W / g] - 2.8 [W / g], for example, 2.1 [W / g].

[0220] If the shape of battery cells 458, 460, 462, and 464 is of type 21700, the weight of the battery pack 410 is in the range of 280 [g] - 440 [g], for example, in the range of 320 [g] - 400 [g], for example, 360 [g]. In this case, the rated voltage of the battery pack 410 is in the range of 6.48 [V] - 7.92 [V], for example, in the range of 6.84 [V] - 7.56 [V], for example, 7.2 [V]. The rated capacity of the battery pack 410 is in the range of 6.0 [Ah] - 12.0 [Ah], for example, in the range of 6.0 [Ah] - 11.0 [Ah], for example, 10.0 [Ah]. The energy capacity of the battery pack 410 is in the range of 38.9 [Wh] - 95.0 [Wh], for example, in the range of 43.2 [Wh] - 79.2 [Wh], for example, 72.0 [Wh]. The continuous discharge output of the battery pack 410 is in the range of 600 [W] - 1570 [W], for example, in the range of 600 [W] - 1460 [W], for example, in the range of 720 [W] - 1090 [W], for example, 830 [W]. The continuous discharge output per unit mass of the battery pack 410 is in the range of 1.4 [W / g] - 5.6 [W / g], for example, in the range of 1.6 [W / g] - 4.3 [W / g], for example, in the range of 2.0 [W / g] - 3.0 [W / g], for example, 2.3 [W / g].

[0221] Figure 50 shows an example of the circuit configuration of the battery pack 410 and the electrical device 404. The battery pack 410, like the battery pack 410, further includes a fuse link 330, a cell temperature detection circuit 332, a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. The power supply circuit 334, the current detection circuit 336, the AFE 338, the MCU 340, the voltage detection circuit 342, the protection FET circuit 344, the FET temperature detection circuit 346, the charger detection circuit 348, and the input / output control circuit 350 are provided on the circuit board 468.

[0222] The total number of pins in the MCU 340 of the battery pack 410 is in the range of 33-100, for example, in the range of 33-60, for example, 48. The ROM capacity of the MCU 340 of the battery pack 410 is in the range of 64 [kByte]-1024 [kByte], for example, in the range of 64 [kByte]-256 [kByte], for example, 128 [kByte]. The RAM capacity of the MCU 340 of the battery pack 410 is in the range of 5 [kByte]-32 [kByte], for example, in the range of 6 [kByte]-16 [kByte], for example, 7 [kByte]. The CPU clock frequency of the MCU 340 of the battery pack 410 is in the range of 19.3 [MHz] - 128.0 [MHz], for example, in the range of 25.6 [MHz] - 48.0 [MHz], for example, 32.0 [MHz]. The number of parallel FETs in the protection FET circuit 344 of the battery pack 410 is in the range of 0 - 4, for example, in the range of 1 - 4, for example, in the range of 2 - 3, for example, 2. The ON resistance of each FET in the protection FET circuit 344 of the battery pack 410 is in the range of 0.10 [mΩ] - 0.59 [mΩ], for example, in the range of 0.30 [mΩ] - 0.50 [mΩ], for example, 0.45 [mΩ]. The total ON resistance of the protection FET circuit 344 of the battery pack 410 is in the range of 0.05 [mΩ] - 0.29 [mΩ], for example, in the range of 0.15 [mΩ] - 0.25 [mΩ], for example, 0.23 [mΩ].

[0223] (Configuration of Battery Pack 412) Battery pack 412 has a configuration that is almost identical to that of battery pack 410. The following mainly describes the differences between battery pack 412 and battery pack 410.

[0224] As shown in Figure 32, the battery pack 412 is equipped with battery cells 498, 500, 502, and 504 instead of battery cells 458, 460, 462, and 464. The battery cells 498, 500, 502, and 504 are arranged in two rows vertically and two columns horizontally, with their longitudinal direction aligned with the front-to-back direction. Battery cells 498 and 500 are electrically connected in parallel via lead plates 470 to form a battery cell pair 506. Battery cells 502 and 504 are electrically connected in parallel via lead plates 470 to form a battery cell pair 508. Battery cell pairs 506 and 508 are electrically connected in series via lead plates 470.

[0225] Battery cells 498, 500, 502, and 504 all have the same configuration as battery cell 100 of Example 1. That is, battery cells 498, 500, 502, and 504 are tab-type battery cells.

[0226] If the shape of battery cells 498, 500, 502, and 504 is of the 18650 type, the weight of the battery pack 412 is in the range of 220 [g] - 340 [g], for example, in the range of 250 [g] - 310 [g], for example, 280 [g]. In this case, the rated voltage of the battery pack 412 is in the range of 6.48 [V] - 7.92 [V], for example, in the range of 6.84 [V] - 7.56 [V], for example, 7.2 [V]. The rated capacity of the battery pack 412 is in the range of 4.0 [Ah] - 8.0 [Ah], for example, in the range of 4.0 [Ah] - 7.0 [Ah], for example, 6.0 [Ah]. The energy capacity of the battery pack 412 is in the range of 25.9 [Wh] - 63.4 [Wh], for example, in the range of 28.8 [Wh] - 50.4 [Wh], for example, 43.2 [Wh]. The continuous discharge output of the battery pack 412 is in the range of 120 [W] - 460 [W], for example, in the range of 140 [W] - 460 [W], for example, in the range of 230 [W] - 370 [W], for example, 310 [W]. The continuous discharge output per unit mass of the battery pack 412 is in the range of 0.4 [W / g] - 2.1 [W / g], for example, in the range of 0.4 [W / g] - 1.6 [W / g], for example, in the range of 0.8 [W / g] - 1.3 [W / g], for example, 1.1 [W / g].

[0227] If the shape of battery cells 498, 500, 502, and 504 is of type 21700, the weight of the battery pack 412 is in the range of 280 [g] - 440 [g], for example, in the range of 320 [g] - 400 [g], for example, 360 [g]. In this case, the rated voltage of the battery pack 412 is in the range of 6.48 [V] - 7.92 [V], for example, in the range of 6.84 [V] - 7.56 [V], for example, 7.2 [V]. The rated capacity of the battery pack 412 is in the range of 6.0 [Ah] - 12.0 [Ah], for example, in the range of 6.0 [Ah] - 11.0 [Ah], for example, 10.0 [Ah]. The energy capacity of the battery pack 412 is in the range of 38.9 [Wh] - 95.0 [Wh], for example, in the range of 43.2 [Wh] - 79.2 [Wh], for example, 72.0 [Wh]. The continuous discharge output of the battery pack 412 is in the range of 120 [W] - 590 [W], for example, in the range of 140 [W] - 590 [W], for example, in the range of 260 [W] - 490 [W], for example, 390 [W]. The continuous discharge output per unit mass of the battery pack 412 is in the range of 0.3 [W / g] - 2.1 [W / g], for example, in the range of 0.3 [W / g] - 1.6 [W / g], for example, in the range of 0.7 [W / g] - 1.3 [W / g], for example, 1.0 [W / g].

[0228] In the battery pack 412, the height H12 (see Figure 32) from the mounting surface of the positive power terminal 492 (or negative power terminal 494) (i.e., the upper surface of the circuit board 468) to the upper end of the positive power terminal 492 (or negative power terminal 494) is in the range of 7.0 [mm] - 14.0 [mm], for example, in the range of 8.9 [mm] - 12.4 [mm], for example, 10.7 [mm]. In the battery pack 412, the plate thickness of the positive power terminal 492 (or negative power terminal 494) is in the range of 0.30 [mm] - 0.59 [mm], for example, in the range of 0.30 [mm] - 0.45 [mm], for example, in the range of 0.35 [mm] - 0.45 [mm], for example, 0.40 [mm]. In the battery pack 412, the conductivity of the positive power terminal 492 (or negative power terminal 494) is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 1 [%IACS] to 30 [%IACS], for example, 25 [%IACS].

[0229] In the battery pack 412, the lead plate 470 is joined to the positive cell terminal 122 or negative cell terminal 124 of the battery cells 498, 500, 502, and 504 by spot welding. In the battery pack 412, the thickness of the lead plate 470 is within the range of 0.10 [mm] - 1.00 [mm], for example, within the range of 0.10 [mm] - 0.30 [mm], for example, 0.20 [mm], or within the range of 0.10 [mm] - 0.19 [mm], within the range of 0.20 [mm] - 0.29 [mm], within the range of 0.30 [mm] - 0.39 [mm], within the range of 0.40 [mm] - 0.49 [mm], within the range of 0.50 [mm] - 0.59 [mm], within the range of 0.60 [mm] - 0.69 [mm], within the range of 0.70 [mm] - 0.79 [mm], within the range of 0.80 [mm] - 0.89 [mm], or within the range of 0.90 [mm] - 1.00 [mm]. In the battery pack 412, the conductivity of the lead plate 470 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 1 [%IACS] to 30 [%IACS], for example, 25 [%IACS].

[0230] As shown in Figure 50, the battery pack 412, like the battery pack 410, further includes a fuse link 330, a cell temperature detection circuit 332, a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. Note that the battery pack 412 does not necessarily have a fuse link 330. Also, the battery pack 412 does not necessarily have a circuit board 468. Therefore, the battery pack 412 does not necessarily have a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. In this case, the cell temperature detection circuit 332 and the positive cell terminals 122 and / or negative cell terminals 124 of each battery cell 498, 500, 502, 504 may be directly connected to the signal communication terminal 496.

[0231] The total number of pins in the MCU 340 of the battery pack 412 is in the range of 6 to 32, for example, in the range of 16 to 32, for example, 32. The ROM capacity of the MCU 340 of the battery pack 412 is in the range of 8 [kByte] to 63 [kByte], for example, in the range of 16 [kByte] to 32 [kByte], for example, 32 [kByte]. The RAM capacity of the MCU 340 of the battery pack 412 is in the range of 1 [kByte] to 4 [kByte], for example, in the range of 2 [kByte] to 4 [kByte], for example, 4 [kByte]. The CPU clock frequency of the MCU 340 of the battery pack 412 is in the range of 4.8 [MHz] to 19.2 [MHz], for example, in the range of 14.4 [MHz] to 17.6 [MHz], for example, 16.0 [MHz]. The number of FETs in parallel of the protection FET circuit 344 of the battery pack 412 is in the range of 0 to 3, for example, in the range of 0 to 2, for example, in the range of 1 to 2, for example, 1. The ON resistance of each FET in the protection FET circuit 344 of the battery pack 412 is in the range of 0.60 [mΩ] to 5.00 [mΩ], for example, in the range of 0.60 [mΩ] to 1.00 [mΩ], for example, 0.65 [mΩ]. The total ON resistance of the protection FET circuit 344 of the battery pack 412 is in the range of 0.30 [mΩ] to 5.00 [mΩ], for example, in the range of 0.30 [mΩ] to 0.50 [mΩ], for example, 0.33 [mΩ].

[0232] The features of the battery packs 406 and 408 in this embodiment are summarized in Tables 7 and 8 below.

[0233]

[0234]

[0235] The features of the battery packs 410 and 412 of this embodiment are summarized in Tables 9 and 10 below.

[0236]

[0237]

[0238] The battery packs 406, 408, 410, and 412 of this embodiment, which have a rated voltage in the range of 6.48 [V] to 7.92 [V], can be made smaller and lighter than the battery packs 12, 14, 16, and 18 of Embodiment 1, which have a rated voltage in the range of 9.72 [V] to 11.88 [V]. In addition, the battery packs 406 and 410, which use tablet-type battery cells 414, 416, 458, 460, 462, and 464, can achieve higher output than the battery packs 408 and 412, which use tab-type battery cells 454, 456, 498, 500, 502, and 504.

[0239] (Example 4) As shown in Figure 35, the electrical equipment system 602 of this embodiment comprises an electrical device 604 and battery packs 606, 608, 610, and 612. One of the battery packs 606, 608, 610, and 612 can be selectively attached to the electrical device 604. The electrical device 604 is an electrical device that operates using power supplied from the battery packs 606, 608, 610, and 612. The electrical device 604 may be, for example, a power tool that uses a motor as a power source, such as a driver drill or an impact driver, or a motor-powered work machine that uses a motor as a power source, such as a hedge trimmer or a hand saw. Alternatively, the electrical device 604 may be an electrical device that does not have a motor, such as a light, radio, or speaker. Alternatively, the electrical device 604 may be a charger that charges the battery packs 606, 608, 610, and 612.

[0240] (Configuration of electrical device 604) As shown in Figures 36 and 37, the electrical device 604 is equipped with a battery pack mounting section 614. The battery packs 606, 608, 610, and 612 can be attached to the battery pack mounting section 614 by inserting them into the battery pack mounting section 614 in a predetermined insertion direction. That is, the battery packs 606, 608, 610, and 612 are stick-type battery packs. Hereinafter, when attaching the battery packs 606, 608, 610, and 612 to the battery pack mounting section 614, the direction in which the battery packs 606, 608, 610, and 612 are inserted will be referred to as the upward direction, and when removing the battery packs 606, 608, 610, and 612 from the battery pack mounting section 614, the direction in which the battery packs 606, 608, 610, and 612 are removed will be referred to as the downward direction. Furthermore, the direction perpendicular to the vertical direction is called the front-back direction, and the direction perpendicular to both the front-back and vertical directions is called the left-right direction.

[0241] As shown in Figure 38, the battery pack mounting portion 614 is provided with an insertion recess 616, a device-side terminal 618, an engagement groove 620, and a guide groove 622. The insertion recess 616 has a shape that allows it to engage with the insertion protrusions 652 (see Figures 41 and 43) of the battery packs 606, 608, 610, and 612 so as to be movable in the vertical direction. The device-side terminal 618 is provided on the upper bottom surface of the insertion recess 616. The device-side terminal 618 is equipped with a positive power terminal 624 and a negative power terminal 626 for charging or discharging power between the electrical equipment 604 and the battery packs 606, 608, 610, and 612. The device-side terminal 618 may also be equipped with a signal communication terminal (not shown) for signal communication between the electrical equipment 604 and the battery packs 606, 608, 610, and 612. The engagement groove 620 is equipped with a right-side engagement groove 628 and a left-side engagement groove 630. The right-side engagement groove 628 is formed near the lower end of the right inner surface of the insertion recess 616 and is recessed toward the right. The left-side engagement groove 630 is formed near the lower end of the left inner surface of the insertion recess 616 and is recessed toward the left. The guide groove 622 includes a right-side guide groove 632 and a left-side guide groove 634. The right-side guide groove 632 is formed on the right inner surface of the insertion recess 616 and is recessed toward the right. The right-side guide groove 632 is offset rearward from the center in the front-rear direction of the insertion recess 616 and extends in the vertical direction. The left-side guide groove 634 is formed on the left inner surface of the insertion recess 616 and is recessed toward the left. The left-side guide groove 634 is offset rearward from the center in the front-rear direction of the insertion recess 616 and extends in the vertical direction.

[0242] (Configuration of Battery Pack 606) As shown in Figure 39, the battery pack 606 comprises battery cells 636 and 638, a cell holder 640, a lead plate 642, battery-side terminals 644, and a casing 646. As shown in Figure 40, the battery cells 636 and 638 are arranged front to back with their longitudinal direction aligned with the vertical direction. Battery cell 638 is located behind battery cell 636. The battery cells 636 and 638 are electrically connected in series via the lead plate 642. The cell holder 640 holds the battery cells 636 and 638. The battery-side terminals 644 are held by the cell holder 640 above it. As shown in Figure 39, the casing 646 houses the battery cells 636 and 638, the cell holder 640, the lead plate 642, and the battery-side terminals 644.

[0243] As shown in Figure 41, the casing 646 comprises a lower casing 648 and an upper casing 650. The upper casing 650 has an insertion projection 652, a terminal opening 654, and guide ribs 656. The insertion projection 652 has a shape corresponding to the insertion recess 616 (see Figure 38) of the battery pack mounting portion 614. The insertion projection 652 is located at the upper end of the upper casing 650 and has a tip surface 658 that extends planarly along the front-rear and left-right directions, and a side surface 660 that extends downward from the periphery of the tip surface 658. The terminal opening 654 is located corresponding to the device-side terminal 618 (see Figure 38) of the battery pack mounting portion 614 and has a shape that allows the device-side terminal 618 to pass through when the battery pack 606 is attached to the electrical equipment 604. The guide ribs 656 comprises a right-side guide rib 662 and a left-side guide rib 664. The right-side guide rib 662 protrudes to the right from the right-side surface 660 of the insertion projection 652 and extends downward from the tip surface 658 of the insertion projection 652. The left-side guide rib 664 protrudes to the left from the left-side surface 660 of the insertion projection 652 and extends downward from the tip surface 658 of the insertion projection 652. The right-side guide rib 662 and the left-side guide rib 664 are positioned to correspond to the right-side guide groove 632 and the left-side guide groove 634 (see Figure 38) of the battery pack mounting portion 614, respectively.

[0244] An engaging piece 666 is formed on the lower casing 648. The engaging piece 666 engages with the engagement groove 620 (see Figure 38) of the battery pack mounting portion 614 when the insertion projection 652 is inserted into the insertion recess 616 of the battery pack mounting portion 614. The engaging piece 666 is located on the right side of the lower casing 648 and comprises an elastically deformable right-side engaging piece 668 and an elastically deformable left-side engaging piece 670 located on the left side of the lower casing 648. The right-side engaging piece 668 comprises a right-side engaging portion 672 that can engage with the right-side engagement groove 628 (see Figure 38) of the battery pack mounting portion 614, and a right-side operating portion 674 for releasing the engagement between the right-side engagement groove 628 and the right-side engaging portion 672. The left-side engaging piece 670 includes a left-side engaging portion 676 that can engage with the left-side engaging groove 630 (see Figure 38) of the battery pack mounting portion 614, and a left-side operating portion 678 for releasing the engagement between the left-side engaging groove 630 and the left-side engaging portion 676.

[0245] As shown in Figure 40, both battery cells 636 and 638 have the same configuration as battery cell 40 in Embodiment 1. That is, battery cells 636 and 638 are tablet-type battery cells. In this embodiment, the battery pack 606 contains two battery cells 636 and 638 housed in the insertion projection 652 (see Figure 41). Therefore, whether the shape of the battery cells 636 and 638 is 18650 type or 21700 type, the cross-sectional area of ​​the insertion projection 652 can be reduced, and it can be shaped to correspond to the insertion recess 616 (see Figure 38) of the electrical device 604. For example, if the insertion recess 616 of the electrical device 604 is located inside the grip portion when the user holds the electrical device 604, the diameter of the grip portion cannot be made very large, so it is necessary to reduce the cross-sectional area of ​​the insertion recess 616. Even in such cases, the battery pack 606 can be attached to the electrical equipment 604 because, regardless of whether the shape of the battery cells 636 and 638 is of the 18650 type or the 21700 type, the cross-sectional area of ​​the insertion projection 652 can be reduced.

[0246] The battery-side terminal 644 includes a positive power terminal 680 and a negative power terminal 682 for charging or discharging power between the electrical device 604 and the battery pack 606, and signal communication terminals 684 and 686 for signal communication between the electrical device 604 and the battery pack 606. The positive power terminal 680 and the negative power terminal 682 are positioned to correspond to the positive power terminal 624 and the negative power terminal 626 of the electrical device 604 (see Figure 38). The signal communication terminals 684 and 686 are positioned to correspond to the signal communication terminals (not shown) of the electrical device 604. When the battery pack 606 is attached to the electrical device 604, the positive power terminal 680 and the negative power terminal 682 mechanically engage with and electrically connect to the positive power terminal 624 and the negative power terminal 626 of the electrical device 604 by clamping them from the left and right directions with their respective clamping portions 680a and 682a. When the battery pack 606 is attached to the electrical device 604, the signal communication terminals 684 and 686 electrically connect to the corresponding signal communication terminals (not shown) of the electrical device 604 by contacting them.

[0247] As shown in Figure 41, terminal openings 654 corresponding to the positive power terminal 680 and the negative power terminal 682 are located on the tip surface 658. Terminal openings 654 corresponding to the signal communication terminals 684 and 686 are located so as to span the tip surface 658 and the side surface 660.

[0248] As shown in Figure 42, the length from the front end to the rear end of the clamping portion 680a of the positive power terminal 680 is the same as the length from the front end to the rear end of the clamping portion 682a of the negative power terminal 682. The width from the right end to the left end of the clamping portion 680a of the positive power terminal 680 is the same as the width from the right end to the left end of the clamping portion 682a of the negative power terminal 682. The height from the lower end to the upper end of the clamping portion 680a of the positive power terminal 680 is the same as the height from the lower end to the upper end of the clamping portion 682a of the negative power terminal 682.

[0249] The plate thickness of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) is in the range of 0.46 [mm] - 1.00 [mm], for example, in the range of 0.60 [mm] - 0.80 [mm], for example, in the range of 0.60 [mm] - 0.70 [mm], for example, 0.60 [mm]. The conductivity of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) is in the range of 1 [%IACS] - 106 [%IACS], for example, in the range of 31 [%IACS] - 106 [%IACS], for example, 40 [%IACS]. The plate thickness of the signal communication terminals 684 and 686 is in the range of 0.30 [mm] to 0.59 [mm], for example, in the range of 0.30 [mm] to 0.45 [mm], for example, in the range of 0.35 [mm] to 0.45 [mm], and for example, 0.40 [mm]. The conductivity of the signal communication terminals 684 and 686 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 1 [%IACS] to 30 [%IACS], and for example, 25 [%IACS].

[0250] If the shape of the battery cells 636 and 638 is of the 18650 type, the length L13 from the front end to the rear end of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) is in the range of 3.0 [mm] to 14.0 [mm], for example, in the range of 5.8 [mm] to 11.3 [mm], for example, 8.5 [mm]. The length L14 from the front end to the rear end of the insertion projection 652 of the casing 646 is in the range of 36.0 [mm] to 48.0 [mm], for example, in the range of 38.0 [mm] to 44.0 [mm], for example, 40.0 [mm]. The ratio of the length L13 of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) from its front end to its rear end to the length L14 of the insertion projection 652 of the casing 646 from its front end to its rear end is in the range of 6.3 [%] - 38.9 [%], for example, in the range of 13.2 [%] - 29.7 [%], for example, 21.3 [%]. The length L15 of the engaging piece 666 of the casing 646 from its front end to its rear end is in the range of 41.0 [mm] - 55.0 [mm], for example, in the range of 44.0 [mm] - 51.0 [mm], for example, 46.0 [mm]. The width W13 from the right end to the left end of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) is in the range of 2.2 [mm] - 7.0 [mm], for example, in the range of 3.4 [mm] - 5.8 [mm], for example, 4.6 [mm]. The width W14 from the right end to the left end of the portion of the insertion projection 652 of the casing 646 excluding the guide ribs 662 and 664 is in the range of 20.5 [mm] - 27.4 [mm], for example, in the range of 21.7 [mm] - 25.1 [mm], for example, 22.8 [mm]. The ratio of the width W13 of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) from right to left to the width W14 of the portion of the insertion projection 652 of the casing 646 excluding the guide ribs 662 and 664 from right to left is within the range of 8.0 [%] - 34.1 [%], for example, within the range of 13.6 [%] - 26.8 [%], for example, 20.2 [%].The width W15 from the right end to the left end of the engaging piece 666 of the casing 646 is in the range of 28.0 [mm] - 37.0 [mm], for example, in the range of 30.0 [mm] - 34.0 [mm], for example, 31.0 [mm]. The height H13 (see Figure 39) from the lower end to the upper end of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) is in the range of 3.0 [mm] - 15.0 [mm], for example, in the range of 8.6 [mm] - 15.0 [mm], for example, 10.0 [mm]. The height H14 (see Figure 39) from the lower end of the casing 646 to the tip surface 658 is in the range of 70.0 [mm] - 90.0 [mm], for example, in the range of 72.0 [mm] - 76.0 [mm], for example, 73.0 [mm]. The height H15 (see Figure 39) from the engagement surface to the tip surface 658 of the right-side engagement portion 672 and the left-side engagement portion 676 of the casing 646 is in the range of 38.0 [mm] to 44.0 [mm], for example, in the range of 39.0 [mm] to 42.0 [mm], for example, 40.0 [mm].

[0251] If the shape of the battery cells 636 and 638 is of type 21700, the length L13 from the front end to the rear end of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) is in the range of 3.0 [mm] to 14.0 [mm], for example, in the range of 5.8 [mm] to 11.3 [mm], for example, 8.5 [mm]. The length L14 from the front end to the rear end of the insertion projection 652 of the casing 646 is in the range of 41.0 [mm] to 55.0 [mm], for example, in the range of 44.0 [mm] to 51.0 [mm], for example, 46.0 [mm]. The ratio of the length L13 from the front end to the rear end of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) to the length L14 from the front end to the rear end of the insertion projection 652 of the casing 646 is in the range of 5.5 [%] - 34.1 [%], for example, in the range of 11.4 [%] - 25.7 [%], for example, 18.5 [%]. The length L15 from the front end to the rear end of the engaging piece 666 of the casing 646 is in the range of 47.0 [mm] - 62.0 [mm], for example, in the range of 50.0 [mm] - 57.0 [mm], for example, 52.0 [mm]. The width W13 from the right end to the left end of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) is in the range of 2.2 [mm] - 7.0 [mm], for example, in the range of 3.4 [mm] - 5.8 [mm], for example, 4.6 [mm]. The width W14 from the right end to the left end of the portion of the insertion projection 652 of the casing 646 excluding the guide ribs 662 and 664 is in the range of 23.2 [mm] - 31.0 [mm], for example, in the range of 24.5 [mm] - 28.4 [mm], for example, 25.8 [mm]. The ratio of the width W13 from the right end to the left end of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) to the width W14 from the right end to the left end of the portion of the insertion projection 652 of the casing 646 excluding the guide ribs 662 and 664 is in the range of 7.1 [%] - 30.1 [%], for example, in the range of 12.0 [%] - 23.7 [%], for example, 17.8 [%].The width W15 from the right end to the left end of the engaging piece 666 of the casing 646 is in the range of 31.0 [mm] - 41.0 [mm], for example, in the range of 33.0 [mm] - 38.0 [mm], for example, 34.0 [mm]. The height H13 (see Figure 39) from the lower end to the upper end of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) is in the range of 3.0 [mm] - 15.0 [mm], for example, in the range of 8.6 [mm] - 15.0 [mm], for example, 10.0 [mm]. The height H14 (see Figure 39) from the lower end of the casing 646 to the tip surface 658 is in the range of 74.0 [mm] - 96.0 [mm], for example, in the range of 76.0 [mm] - 87.0 [mm], for example, 78.0 [mm]. The height H15 (see Figure 39) from the engagement surface to the tip surface 658 of the right-side engagement portion 672 and the left-side engagement portion 676 of the casing 646 is in the range of 43.0 [mm] - 51.0 [mm], for example, in the range of 44.0 [mm] - 49.0 [mm], for example, 46.0 [mm].

[0252] As shown in Figure 40, the lead plate 642 is joined to the positive cell terminal 90 or negative cell terminal 92 (see Figure 7) of the battery cells 636 and 638 by laser welding or spot welding. The thickness of the lead plate 642 is within the range of 0.10 [mm] - 1.00 [mm], for example, within the range of 0.31 [mm] - 1.00 [mm], for example, 0.50 [mm], or within the range of 0.10 [mm] - 0.19 [mm], within the range of 0.20 [mm] - 0.29 [mm], within the range of 0.30 [mm] - 0.39 [mm], within the range of 0.40 [mm] - 0.49 [mm], within the range of 0.50 [mm] - 0.59 [mm], within the range of 0.60 [mm] - 0.69 [mm], within the range of 0.70 [mm] - 0.79 [mm], within the range of 0.80 [mm] - 0.89 [mm], or within the range of 0.90 [mm] - 1.00 [mm]. The conductivity of the lead plate 642 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 31 [%IACS] to 106 [%IACS], for example, 40 [%IACS].

[0253] If the shape of the battery cells 636 and 638 is of the 18650 type, the weight of the battery pack 606 is in the range of 90 [g] - 150 [g], for example, in the range of 100 [g] - 140 [g], for example, 120 [g]. In this case, the rated voltage of the battery pack 606 is in the range of 6.48 [V] - 7.92 [V], for example, in the range of 6.84 [V] - 7.56 [V], for example, 7.2 [V]. The rated capacity of the battery pack 606 is in the range of 2.0 [Ah] - 4.0 [Ah], for example, in the range of 2.0 [Ah] - 3.5 [Ah], for example, 3.0 [Ah]. The energy capacity of the battery pack 606 is in the range of 13.0 [Wh] - 31.7 [Wh], for example, in the range of 14.4 [Wh] - 25.2 [Wh], for example, 21.6 [Wh]. The continuous discharge output of the battery pack 606 is in the range of 230 [W] - 540 [W], for example, in the range of 230 [W] - 510 [W], for example, in the range of 270 [W] - 390 [W], for example, 300 [W]. The continuous discharge output per unit mass of the battery pack 606 is in the range of 1.5 [W / g] - 6.0 [W / g], for example, in the range of 1.9 [W / g] - 4.5 [W / g], for example, in the range of 2.2 [W / g] - 3.2 [W / g], for example, 2.5 [W / g].

[0254] If the shape of the battery cells 636 and 638 is of type 21700, the weight of the battery pack 606 is in the range of 130 [g] - 200 [g], for example, in the range of 140 [g] - 190 [g], for example, 165 [g]. In this case, the rated voltage of the battery pack 606 is in the range of 6.48 [V] - 7.92 [V], for example, in the range of 6.84 [V] - 7.56 [V], for example, 7.2 [V]. The rated capacity of the battery pack 606 is in the range of 3.0 [Ah] - 6.0 [Ah], for example, in the range of 3.0 [Ah] - 5.5 [Ah], for example, 5.0 [Ah]. The energy capacity of the battery pack 606 is in the range of 19.4 [Wh] - 47.5 [Wh], for example, in the range of 21.6 [Wh] - 39.6 [Wh], for example, 36.0 [Wh]. The continuous discharge output of the battery pack 606 is in the range of 300 [W] - 780 [W], for example, in the range of 300 [W] - 730 [W], for example, in the range of 360 [W] - 550 [W], for example, 410 [W]. The continuous discharge output per unit mass of the battery pack 606 is in the range of 1.5 [W / g] - 6.0 [W / g], for example, in the range of 1.8 [W / g] - 4.7 [W / g], for example, in the range of 2.1 [W / g] - 3.3 [W / g], for example, 2.4 [W / g].

[0255] Figure 51 shows an example of the circuit configuration of the battery pack 606 and the electrical device 604. In Figure 51, the circuit board 370 is housed inside the casing 646, and the positive power terminal 680 and negative power terminal 682 of the battery-side terminal 644, and the signal communication terminals 684 and 686 are connected to the wiring on the circuit board 370. The battery pack 606, like the battery pack 12 of Embodiment 1, further includes a fuse link 330, a cell temperature detection circuit 332, a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. The power supply circuit 334, current detection circuit 336, AFE 338, MCU 340, voltage detection circuit 342, protection FET circuit 344, FET temperature detection circuit 346, charger detection circuit 348, and input / output control circuit 350 are provided on the circuit board 370.

[0256] The total number of pins in the MCU340 of battery pack 606 is in the range of 33-100, for example, in the range of 33-60, for example, 48. The ROM capacity of the MCU340 of battery pack 606 is in the range of 64 [kByte]-1024 [kByte], for example, in the range of 64 [kByte]-256 [kByte], for example, 128 [kByte]. The RAM capacity of the MCU340 of battery pack 410 is in the range of 5 [kByte]-32 [kByte], for example, in the range of 6 [kByte]-16 [kByte], for example, 7 [kByte]. The CPU clock frequency of the MCU 340 of the battery pack 410 is in the range of 19.3 [MHz] - 128.0 [MHz], for example, in the range of 25.6 [MHz] - 48.0 [MHz], for example, 32.0 [MHz]. The number of parallel FETs in the protection FET circuit 344 of the battery pack 410 is in the range of 0 - 4, for example, in the range of 1 - 4, for example, in the range of 2 - 3, for example, 2. The ON resistance of each FET in the protection FET circuit 344 of the battery pack 410 is in the range of 0.10 [mΩ] - 0.59 [mΩ], for example, in the range of 0.30 [mΩ] - 0.50 [mΩ], for example, 0.45 [mΩ]. The total ON resistance of the protection FET circuit 344 of the battery pack 410 is in the range of 0.05 [mΩ] - 0.29 [mΩ], for example, in the range of 0.15 [mΩ] - 0.25 [mΩ], for example, 0.23 [mΩ].

[0257] (Configuration of Battery Pack 608) Battery pack 608 has a configuration that is almost identical to that of battery pack 606. The following mainly describes the differences between battery pack 608 and battery pack 606.

[0258] As shown in Figure 40, the battery pack 608 includes battery cells 688 and 690 instead of battery cells 636 and 638. Battery cells 688 and 690 are arranged so that their longitudinal direction is aligned with the vertical direction. Battery cells 284 and 286 are arranged side by side behind battery cell 282. Battery cells 688 and 690 are electrically connected in series.

[0259] The battery cells 688 and 690 both have the same configuration as the battery cell 100 of Embodiment 1. That is, the battery cells 688 and 690 are tab-type battery cells. In the battery pack 608 of this embodiment, there are two battery cells 688 and 690 housed in the insertion projection 652 (see Figure 41). Therefore, whether the shape of the battery cells 688 and 690 is 18650 type or 21700 type, the cross-sectional area of ​​the insertion projection 652 can be reduced, and it can be shaped to correspond to the insertion recess 616 (see Figure 38) of the electrical device 604. For example, if the insertion recess 616 of the electrical device 604 is located inside the grip portion when the user grasps the electrical device 604, the diameter of the grip portion cannot be made very large, so it is necessary to reduce the cross-sectional area of ​​the insertion recess 616. Even in such cases, the battery pack 608 can be attached to the electrical equipment 604 because, regardless of whether the shape of the battery cells 688 and 690 is of the 18650 type or the 21700 type, the cross-sectional area of ​​the insertion projection 652 can be reduced.

[0260] If the shape of the battery cells 688 and 690 is of the 18650 type, the weight of the battery pack 608 is in the range of 90 [g] - 150 [g], for example, in the range of 100 [g] - 140 [g], for example, 120 [g]. In this case, the rated voltage of the battery pack 608 is in the range of 6.48 [V] - 7.92 [V], for example, in the range of 6.84 [V] - 7.56 [V], for example, 7.2 [V]. The rated capacity of the battery pack 608 is in the range of 2.0 [Ah] - 4.0 [Ah], for example, in the range of 2.0 [Ah] - 3.5 [Ah], for example, 3.0 [Ah]. The energy capacity of the battery pack 608 is in the range of 13.0 [Wh] - 31.7 [Wh], for example, in the range of 14.4 [Wh] - 25.2 [Wh], for example, 21.6 [Wh]. The continuous discharge output of the battery pack 608 is in the range of 60 [W] - 230 [W], for example, in the range of 70 [W] - 230 [W], for example, in the range of 120 [W] - 190 [W], for example, 160 [W]. The continuous discharge output per unit mass of the battery pack 608 is in the range of 0.4 [W / g] - 2.6 [W / g], for example, in the range of 0.5 [W / g] - 1.9 [W / g], for example, in the range of 1.0 [W / g] - 1.5 [W / g], for example, 1.3 [W / g].

[0261] If the shape of the battery cells 688 and 690 is of type 21700, the weight of the battery pack 608 is in the range of 130 [g] - 200 [g], for example, in the range of 140 [g] - 190 [g], for example, 165 [g]. In this case, the rated voltage of the battery pack 608 is in the range of 6.48 [V] - 7.92 [V], for example, in the range of 6.84 [V] - 7.56 [V], for example, 7.2 [V]. The rated capacity of the battery pack 608 is in the range of 3.0 [Ah] - 6.0 [Ah], for example, in the range of 3.0 [Ah] - 5.5 [Ah], for example, 5.0 [Ah]. The energy capacity of the battery pack 608 is in the range of 19.4 [Wh] - 47.5 [Wh], for example, in the range of 21.6 [Wh] - 39.6 [Wh], for example, 36.0 [Wh]. The continuous discharge output of the battery pack 608 is in the range of 60 [W] - 300 [W], in the range of 70 [W] - 300 [W], for example, in the range of 130 [W] - 240 [W], for example, 200 [W]. The continuous discharge output per unit mass of the battery pack 608 is in the range of 0.3 [W / g] - 2.3 [W / g], for example, in the range of 0.3 [W / g] - 1.8 [W / g], for example, in the range of 0.7 [W / g] - 1.4 [W / g], for example, 1.2 [W / g].

[0262] In the battery pack 608, the height H13 (see Figure 39) from the lower end to the upper end of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) is in the range of 3.0 [mm] - 15.0 [mm], for example, in the range of 8.6 [mm] - 15.0 [mm], and for example, 10.0 [mm]. In the battery pack 608, the plate thickness of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) is in the range of 0.30 [mm] - 0.59 [mm], for example, in the range of 0.30 [mm] - 0.45 [mm], for example, in the range of 0.35 [mm] - 0.45 [mm], and for example, 0.40 [mm]. In the battery pack 608, the conductivity of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 1 [%IACS] to 30 [%IACS], for example, 25 [%IACS].

[0263] In the battery pack 608, the lead plate 642 is joined to the positive cell terminal 122 or negative cell terminal 124 (see Figure 7) of the battery cells 688 and 690 by spot welding. In the battery pack 608, the thickness of the lead plate 642 is within the range of 0.10 [mm] - 1.00 [mm], for example, within the range of 0.10 [mm] - 0.30 [mm], for example, 0.20 [mm], or within the range of 0.10 [mm] - 0.19 [mm], within the range of 0.20 [mm] - 0.29 [mm], within the range of 0.30 [mm] - 0.39 [mm], within the range of 0.40 [mm] - 0.49 [mm], within the range of 0.50 [mm] - 0.59 [mm], within the range of 0.60 [mm] - 0.69 [mm], within the range of 0.70 [mm] - 0.79 [mm], within the range of 0.80 [mm] - 0.89 [mm], or within the range of 0.90 [mm] - 1.00 [mm]. In the battery pack 608, the conductivity of the lead plate 642 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 1 [%IACS] to 30 [%IACS], for example, 25 [%IACS].

[0264] As shown in Figure 51, the battery pack 608, like the battery pack 606, further includes a fuse link 330, a cell temperature detection circuit 332, a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. Note that the battery pack 608 does not necessarily have a fuse link 330. Also, the battery pack 608 does not necessarily have a circuit board 370. Therefore, the battery pack 608 does not necessarily have a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. In this case, the cell temperature detection circuit 332 and the positive cell terminals 122 and / or negative cell terminals 124 of each battery cell 688, 690 may be directly connected to the signal communication terminals 684, 686.

[0265] The total number of pins in the MCU340 of the battery pack 608 is in the range of 6 to 32, for example, in the range of 16 to 32, for example, 32. The ROM capacity of the MCU340 of the battery pack 608 is in the range of 8 [kByte] to 63 [kByte], for example, in the range of 16 [kByte] to 32 [kByte], for example, 32 [kByte]. The RAM capacity of the MCU340 of the battery pack 608 is in the range of 1 [kByte] to 4 [kByte], for example, in the range of 2 [kByte] to 4 [kByte], for example, 4 [kByte]. The CPU clock frequency of the MCU 340 of the battery pack 608 is in the range of 4.8 [MHz] to 19.2 [MHz], for example, in the range of 14.4 [MHz] to 17.6 [MHz], for example, 16.0 [MHz]. The number of parallel FETs in the protection FET circuit 344 of the battery pack 608 is in the range of 0 to 3, for example, in the range of 0 to 2, for example, in the range of 1 to 2, for example, 1. The ON resistance of each FET in the protection FET circuit 344 of the battery pack 608 is in the range of 0.60 [mΩ] to 5.00 [mΩ], for example, in the range of 0.60 [mΩ] to 1.00 [mΩ], for example, 0.65 [mΩ]. The total ON resistance of the protection FET circuit 344 of the battery pack 608 is in the range of 0.30 [mΩ] to 5.00 [mΩ], for example, in the range of 0.30 [mΩ] to 0.50 [mΩ], for example, 0.33 [mΩ].

[0266] (Configuration of Battery Pack 610) Battery pack 610 has a configuration that is partially the same as that of battery pack 606. The following mainly describes the differences between battery pack 610 and battery pack 606.

[0267] As shown in Figure 43, the battery pack 610 comprises battery cells 692, 694, 696, and 698, a cell holder 640 (see Figure 40), a lead plate 642 (see Figure 40), a battery-side terminal 644 (see Figure 40), and a casing 700. The casing 700 comprises a lower casing 702 and an upper casing 650. The lower casing 702 comprises an engaging piece 666 and a battery cell housing portion 704. The battery cells 692 and 694 are housed in insertion projections 652 of the upper casing 650. The battery cells 692 and 694 are arranged front to back so that their longitudinal direction is aligned with the vertical direction. Battery cell 694 is located behind battery cell 692. The battery cells 692 and 694 are electrically connected in series via the lead plate 642 to form a battery cell pair 706. The battery cells 696 and 698 are housed in the battery cell housing section 704 of the lower casing 702. The battery cells 696 and 698 are arranged side by side, with their longitudinal direction aligned with the front-to-back direction. Battery cell 698 is located to the left of battery cell 696. The battery cells 696 and 698 are electrically connected in series via lead plates 642 to form a battery cell pair 708. The battery cell pair 706 and 708 are electrically connected in parallel via lead plates 642.

[0268] Battery cells 692, 694, 696, and 698 all have the same configuration as battery cell 40 of Example 1. That is, battery cells 692, 694, 696, and 698 are tablet-type battery cells. The shape of battery cells 692, 694, 696, and 698 is all of the 18650 type. Alternatively, the shape of battery cells 692, 694, 696, and 698 is all of the 21700 type.

[0269] If the shape of battery cells 692, 694, 696, and 698 is of the 18650 type, the weight of the battery pack 610 is in the range of 280 [g] - 420 [g], for example, in the range of 310 [g] - 390 [g], for example, 350 [g]. In this case, the rated voltage of the battery pack 610 is in the range of 6.48 [V] - 7.92 [V], for example, in the range of 6.84 [V] - 7.56 [V], for example, 7.2 [V]. The rated capacity of the battery pack 610 is in the range of 4.0 [Ah] - 8.0 [Ah], for example, in the range of 4.0 [Ah] - 7.0 [Ah], for example, 6.0 [Ah]. The energy capacity of the battery pack 610 is in the range of 25.9 [Wh] - 63.4 [Wh], for example, in the range of 28.8 [Wh] - 50.4 [Wh], for example, 43.2 [Wh]. The continuous discharge output of the battery pack 610 is in the range of 460 [W] - 1070 [W], for example, in the range of 460 [W] - 1020 [W], for example, in the range of 540 [W] - 790 [W], for example, 600 [W]. The continuous discharge output per unit mass of the battery pack 610 is in the range of 1.1 [W / g] - 3.8 [W / g], for example, in the range of 1.3 [W / g] - 3.0 [W / g], for example, in the range of 1.5 [W / g] - 2.2 [W / g], for example, 1.7 [W / g]. In the battery pack 610, the length L16 from the front end of the casing 700 (i.e., the front end of the battery cell housing 704) to the rear end of the casing 700 (i.e., the rear end of the battery cell housing 704) is in the range of 83.0 [mm] - 92.0 [mm], for example, in the range of 84.9 [mm] - 89.4 [mm], for example, 86.7 [mm]. In the battery pack 610, the width W16 from the right end of the casing 700 (i.e., the right end of the battery cell housing 704) to the left end of the casing 700 (i.e., the left end of the battery cell housing 704) is in the range of 40.5 [mm] - 46.5 [mm], for example, in the range of 42.0 [mm] - 45.0 [mm], for example, 43.5 [mm].As shown in Figure 44, the height H16 from the lower end of the casing 700 (i.e., the lower end of the battery cell housing 704) to the tip surface 658 is in the range of 102.0 [mm] - 116.0 [mm], for example, in the range of 105.0 [mm] - 111.0 [mm], for example, 107.0 [mm]. The height H17 from the lower end to the upper end of the battery cell housing 704 is in the range of 32.0 [mm] - 35.0 [mm], for example, in the range of 33.0 [mm] - 34.5 [mm], for example, 34.0 [mm].

[0270] If the shape of battery cells 692, 694, 696, and 698 is of type 21700, the weight of the battery pack 610 is in the range of 360 [g] - 540 [g], for example, in the range of 400 [g] - 500 [g], for example, 450 [g]. In this case, the rated voltage of the battery pack 610 is in the range of 6.48 [V] - 7.92 [V], for example, in the range of 6.84 [V] - 7.56 [V], for example, 7.2 [V]. The rated capacity of the battery pack 610 is in the range of 6.0 [Ah] - 12.0 [Ah], for example, in the range of 6.0 [Ah] - 11.0 [Ah], for example, 10.0 [Ah]. The energy capacity of the battery pack 610 is in the range of 38.9 [Wh] - 95.0 [Wh], for example, in the range of 43.2 [Wh] - 79.2 [Wh], for example, 72.0 [Wh]. The continuous discharge output of the battery pack 610 is in the range of 600 [W] - 1570 [W], for example, in the range of 600 [W] - 1460 [W], for example, in the range of 720 [W] - 1090 [W], for example, 830 [W]. The continuous discharge output per unit mass of the battery pack 610 is in the range of 1.1 [W / g] - 4.4 [W / g], for example, in the range of 1.3 [W / g] - 3.4 [W / g], for example, in the range of 1.6 [W / g] - 2.4 [W / g], for example, 1.8 [W / g]. As shown in Figure 43, in the battery pack 610, the length L16 from the front end of the casing 700 (i.e., the front end of the battery cell housing 704) to the rear end of the casing 700 (i.e., the rear end of the battery cell housing 704) is in the range of 87.0 [mm] - 96.0 [mm], for example, in the range of 89.1 [mm] - 93.6 [mm], for example, 91.1 [mm]. In the battery pack 610, the width W16 from the right end of the casing 700 (i.e., the right end of the battery cell housing 704) to the left end of the casing 700 (i.e., the left end of the battery cell housing 704) is in the range of 46.5 [mm] - 56.5 [mm], for example, in the range of 50.1 [mm] - 55.1 [mm], for example, 53.6 [mm].As shown in Figure 44, the height H16 from the lower end of the casing 700 (i.e., the lower end of the battery cell housing 704) to the tip surface 658 is in the range of 110.0 [mm] - 128.0 [mm], for example, in the range of 113.0 [mm] - 122.0 [mm], for example, 116.0 [mm]. The height H17 from the lower end to the upper end of the battery cell housing 704 is in the range of 35.0 [mm] - 47.0 [mm], for example, in the range of 36.0 [mm] - 42.0 [mm], for example, 37.0 [mm].

[0271] In the battery pack 610, the height H13 (see Figure 39) from the lower end to the upper end of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) is within the range of 3.0 [mm] - 15.0 [mm], for example, within the range of 8.6 [mm] - 15.0 [mm], for example, 10.0 [mm]. In the battery pack 610, the plate thickness of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) is within the range of 0.46 [mm] - 1.00 [mm], for example, within the range of 0.60 [mm] - 0.80 [mm], for example, within the range of 0.60 [mm] - 0.70 [mm], for example, 0.60 [mm]. In the battery pack 610, the conductivity of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 31 [%IACS] to 106 [%IACS], for example, 40 [%IACS].

[0272] In the battery pack 610, the lead plate 642 is joined to the positive cell terminal 90 or negative cell terminal 92 (see Figure 7) of the battery cells 692, 694, 696, and 698 by laser welding or spot welding. In the battery pack 610, the thickness of the lead plate 642 is within the range of 0.10 [mm] - 1.00 [mm], for example, within the range of 0.31 [mm] - 1.00 [mm], for example, 0.50 [mm], or within the range of 0.10 [mm] - 0.19 [mm], within the range of 0.20 [mm] - 0.29 [mm], within the range of 0.30 [mm] - 0.39 [mm], within the range of 0.40 [mm] - 0.49 [mm], within the range of 0.50 [mm] - 0.59 [mm], within the range of 0.60 [mm] - 0.69 [mm], within the range of 0.70 [mm] - 0.79 [mm], within the range of 0.80 [mm] - 0.89 [mm], or within the range of 0.90 [mm] - 1.00 [mm]. In the battery pack 610, the conductivity of the lead plate 642 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 31 [%IACS] to 106 [%IACS], for example, 40 [%IACS].

[0273] Figure 52 shows an example of the circuit configuration of the battery pack 610 and the electrical device 604. In Figure 52, the circuit board 370 is housed inside the casing 700, and the positive power terminal 680 and negative power terminal 682 of the battery-side terminal 644, as well as the signal communication terminals 684 and 686, are connected to the wiring on the circuit board 370. The battery pack 610, like the battery pack 606, further includes a fuse link 330, a cell temperature detection circuit 332, a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. The power supply circuit 334, current detection circuit 336, AFE 338, MCU 340, voltage detection circuit 342, protection FET circuit 344, FET temperature detection circuit 346, charger detection circuit 348, and input / output control circuit 350 are provided on the circuit board 370.

[0274] The total number of pins in the MCU340 of battery pack 610 is in the range of 33-100, for example, in the range of 33-60, for example, 48. The ROM capacity of the MCU340 of battery pack 606 is in the range of 64 [kByte]-1024 [kByte], for example, in the range of 64 [kByte]-256 [kByte], for example, 128 [kByte]. The RAM capacity of the MCU340 of battery pack 410 is in the range of 5 [kByte]-32 [kByte], for example, in the range of 6 [kByte]-16 [kByte], for example, 7 [kByte]. The CPU clock frequency of the MCU 340 of the battery pack 410 is in the range of 19.3 [MHz] - 128.0 [MHz], for example, in the range of 25.6 [MHz] - 48.0 [MHz], for example, 32.0 [MHz]. The number of parallel FETs in the protection FET circuit 344 of the battery pack 410 is in the range of 0 - 4, for example, in the range of 1 - 4, for example, in the range of 2 - 3, for example, 2. The ON resistance of each FET in the protection FET circuit 344 of the battery pack 410 is in the range of 0.10 [mΩ] - 0.59 [mΩ], for example, in the range of 0.30 [mΩ] - 0.50 [mΩ], for example, 0.45 [mΩ]. The total ON resistance of the protection FET circuit 344 of the battery pack 410 is in the range of 0.05 [mΩ] - 0.29 [mΩ], for example, in the range of 0.15 [mΩ] - 0.25 [mΩ], for example, 0.23 [mΩ].

[0275] (Configuration of Battery Pack 612) Battery pack 612 has a configuration that is almost identical to that of battery pack 610. The following mainly describes the differences between battery pack 612 and battery pack 610.

[0276] As shown in Figure 43, the battery pack 612 has battery cells 710, 712, 714, and 716 instead of battery cells 692, 694, 696, and 698. Battery cells 710 and 712 are housed in insertion projections 652 of the upper casing 650. Battery cells 710 and 712 are arranged front to back with their longitudinal direction aligned with the vertical direction. Battery cell 712 is located behind battery cell 710. Battery cells 710 and 712 are electrically connected in series to form a battery cell pair 718. Battery cells 714 and 716 are housed in a battery cell housing section 704 of the lower casing 702. Battery cells 714 and 716 are arranged left to right with their longitudinal direction aligned with the front to back direction. Battery cell 716 is located to the left of battery cell 714. Battery cells 714 and 716 are electrically connected in series to form battery cell pair 720. Battery cell pair 718 and 720 are electrically connected in parallel.

[0277] Battery cells 710, 712, 714, and 716 all have the same configuration as battery cell 100 of Example 1. That is, battery cells 710, 712, 714, and 716 are tab-type battery cells. The shape of battery cells 710, 712, 714, and 716 is all of the 18650 type. Alternatively, the shape of battery cells 710, 712, 714, and 716 is all of the 21700 type.

[0278] If the shape of battery cells 710, 712, 714, and 716 is of the 18650 type, the weight of battery pack 612 is in the range of 280 [g] - 420 [g], for example, in the range of 310 [g] - 390 [g], for example, 350 [g]. In this case, the rated voltage of battery pack 612 is in the range of 6.48 [V] - 7.92 [V], for example, in the range of 6.84 [V] - 7.56 [V], for example, 7.2 [V]. The rated capacity of battery pack 612 is in the range of 4.0 [Ah] - 8.0 [Ah], for example, in the range of 4.0 [Ah] - 7.0 [Ah], for example, 6.0 [Ah]. The energy capacity of the battery pack 612 is in the range of 25.9 [Wh] - 63.4 [Wh], for example, in the range of 28.8 [Wh] - 50.4 [Wh], for example, 43.2 [Wh]. The continuous discharge output of the battery pack 612 is in the range of 120 [W] - 460 [W], for example, in the range of 140 [W] - 460 [W], for example, in the range of 230 [W] - 370 [W], for example, 310 [W]. The continuous discharge output per unit mass of the battery pack 612 is in the range of 0.3 [W / g] - 1.6 [W / g], for example, in the range of 0.3 [W / g] - 1.3 [W / g], for example, in the range of 0.6 [W / g] - 1.0 [W / g], for example, 0.8 [W / g].

[0279] If the shape of battery cells 710, 712, 714, and 716 is of type 21700, the weight of battery pack 612 is in the range of 360 [g] - 540 [g], for example, in the range of 400 [g] - 500 [g], for example, 450 [g]. In this case, the rated voltage of battery pack 612 is in the range of 6.48 [V] - 7.92 [V], for example, in the range of 6.84 [V] - 7.56 [V], for example, 7.2 [V]. The rated capacity of battery pack 612 is in the range of 6.0 [Ah] - 12.0 [Ah], for example, in the range of 6.0 [Ah] - 11.0 [Ah], for example, 10.0 [Ah]. The energy capacity of the battery pack 612 is in the range of 38.9 [Wh] - 95.0 [Wh], for example, in the range of 43.2 [Wh] - 79.2 [Wh], for example, 72.0 [Wh]. The continuous discharge output of the battery pack 612 is in the range of 120 [W] - 590 [W], for example, in the range of 140 [W] - 590 [W], for example, in the range of 260 [W] - 490 [W], for example, 390 [W]. The continuous discharge output per unit mass of the battery pack 612 is in the range of 0.2 [W / g] - 1.6 [W / g], for example, in the range of 0.2 [W / g] - 1.3 [W / g], for example, in the range of 0.5 [W / g] - 1.0 [W / g], for example, 0.8 [W / g].

[0280] In the battery pack 612, the height H13 (see Figure 39) from the lower end to the upper end of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) is within the range of 3.0 [mm] - 15.0 [mm], for example, within the range of 8.6 [mm] - 15.0 [mm], and for example, 10.0 [mm]. In the battery pack 612, the plate thickness of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) is within the range of 0.30 [mm] - 0.59 [mm], for example, within the range of 0.30 [mm] - 0.45 [mm], for example, within the range of 0.35 [mm] - 0.45 [mm], and for example, 0.40 [mm]. In the battery pack 612, the conductivity of the clamping portion 680a of the positive power terminal 680 (or the clamping portion 682a of the negative power terminal 682) is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 1 [%IACS] to 30 [%IACS], for example, 25 [%IACS].

[0281] In the battery pack 612, the lead plate 642 is joined to the positive cell terminal 122 or negative cell terminal 124 (see Figure 7) of the battery cells 710, 712, 714, and 716 by spot welding. In the battery pack 612, the thickness of the lead plate 642 is within the range of 0.10 [mm] - 1.00 [mm], for example, within the range of 0.10 [mm] - 0.30 [mm], for example, 0.20 [mm], or within the range of 0.10 [mm] - 0.19 [mm], within the range of 0.20 [mm] - 0.29 [mm], within the range of 0.30 [mm] - 0.39 [mm], within the range of 0.40 [mm] - 0.49 [mm], within the range of 0.50 [mm] - 0.59 [mm], within the range of 0.60 [mm] - 0.69 [mm], within the range of 0.70 [mm] - 0.79 [mm], within the range of 0.80 [mm] - 0.89 [mm], or within the range of 0.90 [mm] - 1.00 [mm]. In the battery pack 612, the conductivity of the lead plate 642 is in the range of 1 [%IACS] to 106 [%IACS], for example, in the range of 1 [%IACS] to 30 [%IACS], for example, 25 [%IACS].

[0282] As shown in Figure 52, the battery pack 612, like the battery pack 610, further includes a fuse link 330, a cell temperature detection circuit 332, a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. Note that the battery pack 612 does not necessarily have a fuse link 330. Also, the battery pack 612 does not necessarily have a circuit board 370. Therefore, the battery pack 612 does not necessarily have a power supply circuit 334, a current detection circuit 336, an AFE 338, an MCU 340, a voltage detection circuit 342, a protection FET circuit 344, an FET temperature detection circuit 346, a charger detection circuit 348, and an input / output control circuit 350. In this case, the cell temperature detection circuit 332 and the positive cell terminals 122 and / or negative cell terminals 124 of each battery cell 710, 712, 714, 716 may be directly connected to the signal communication terminals 684 and 686.

[0283] The total number of pins in the MCU 340 of the battery pack 612 is in the range of 6 to 32, for example, in the range of 16 to 32, for example, 32. The ROM capacity of the MCU 340 of the battery pack 612 is in the range of 8 [kByte] to 63 [kByte], for example, in the range of 16 [kByte] to 32 [kByte], for example, 32 [kByte]. The RAM capacity of the MCU 340 of the battery pack 612 is in the range of 1 [kByte] to 4 [kByte], for example, in the range of 2 [kByte] to 4 [kByte], for example, 4 [kByte]. The CPU clock frequency of the MCU 340 of the battery pack 612 is in the range of 4.8 [MHz] to 19.2 [MHz], for example, in the range of 14.4 [MHz] to 17.6 [MHz], for example, 16.0 [MHz]. The number of parallel FETs in the protection FET circuit 344 of the battery pack 612 is in the range of 0 to 3, for example, in the range of 0 to 2, for example, in the range of 1 to 2, for example, 1. The ON resistance of each FET in the protection FET circuit 344 of the battery pack 612 is in the range of 0.60 [mΩ] to 5.00 [mΩ], for example, in the range of 0.60 [mΩ] to 1.00 [mΩ], for example, 0.65 [mΩ]. The total ON resistance of the protection FET circuit 344 of the battery pack 612 is in the range of 0.30 [mΩ] to 5.00 [mΩ], for example, in the range of 0.30 [mΩ] to 0.50 [mΩ], for example, 0.33 [mΩ].

[0284] The features of the battery packs 606 and 608 in this embodiment are summarized in Tables 11 and 12 below.

[0285]

[0286]

[0287] The features of the battery packs 610 and 612 in this embodiment are summarized in Tables 13 and 14 below.

[0288]

[0289]

[0290] The battery packs 606, 608, 610, and 612 of this embodiment, which have a rated voltage in the range of 6.48 [V] to 7.92 [V], can be made smaller and lighter than the battery packs 212, 214, 216, and 218 of Embodiment 2, which have a rated voltage in the range of 9.72 [V] to 11.88 [V]. In addition, the battery packs 606 and 610, which use the tablet-type battery cells 636, 638, 692, 694, 696, and 698, can achieve higher output than the battery packs 608 and 612, which use the tab-type battery cells 688, 690, 710, 712, 714, and 716.

[0291] (Method for measuring battery pack output, continuous discharge current, and DC internal resistance) In this specification, the output of a battery pack is defined by the power supply voltage and the continuous discharge current of the battery pack. The power supply voltage here is expressed by the following formula, taking into account that the voltage drops due to the DC internal resistance of the battery pack: Output [W] = (Reference voltage [V] - Continuous discharge current [A] × DC internal resistance [mΩ] × 1000) × Continuous discharge current [A] The reference voltage here is, for example, if the battery cell is a lithium-ion battery cell, 4.0 [V] per battery cell, taking into account the voltage drop when the discharge current flows from the fully charged voltage of 4.2 [V].

[0292] The magnitude of the continuous discharge current refers to the maximum current value that can be continuously discharged when a battery cell is charged under the charging conditions recommended by the cell manufacturer, with an ambient temperature of 25 ± 1 [°C], and then discharged to 2 [Ah] when both the ambient temperature and the cell surface temperature are 25 ± 1 [°C]. Discharge stops when either the discharge termination voltage recommended by the cell manufacturer is reached, or the cell surface temperature during discharge recommended by the cell manufacturer is reached, or when either of these conditions is met.

[0293] This specification describes a method for measuring DC internal resistance (DCIR). In this measurement method, first, the depth of discharge (charge level) of the battery cell is set to 50%. Specifically, after properly charging the battery cell, it is discharged to half of its rated capacity. Next, the terminal voltage of the battery cell is measured while it is discharging. At this time, the ambient temperature is maintained at 25 ± 1 °C, and the temperature of the battery cell is also set to 25 ± 1 °C. When discharging the battery cell, the discharge current is changed over time as follows: the discharge current is adjusted to 10 A for the first second, and then to 20 A for the following five seconds. This measurement method is characterized by discharging the battery cell with a high current, taking into account its use in power tools. While discharging the battery cell in this way, the current C1 and voltage V1 at 1 second are measured, and the current C2 and voltage V2 at 6 seconds are measured. The DC internal resistance of the battery cell is then determined from the slope of the current-voltage between the two measured points. In this case, the DC internal resistance R is expressed by the following formula: R = (V1 - V2) / (C2 - C1) × 1000 [mΩ]

[0294] This specification also discloses electrical equipment systems and / or battery packs for each of the following items:

[0295] (Item A1) An electrical equipment system comprising a first battery pack, a second battery pack, and an electrical device, wherein the electrical device is provided with a battery pack mounting portion to which the first battery pack or the second battery pack can be selectively attached or detached, the battery pack mounting portion is provided with an equipment-side power terminal for charging or discharging power between the electrical device and the first battery pack or the second battery pack, the first battery pack comprises three first battery cells electrically connected in series, and a first battery-side power terminal that mechanically engages with and electrically connects to the equipment-side power terminal, the first battery cells are cylindrical in shape, the first battery cells are tablet-type battery cells, the rated voltage of the first battery pack is in the range of 9.72 [V] - 11.88 [V], and the plate thickness of the first battery-side power terminal is in the range of 0.60 [mm] - 1.00 [mm] or in the range of 0.65 [mm] - 1.00 [mm]. An electrical equipment system, wherein the second battery pack comprises three second battery cells electrically connected in series and a second battery-side power terminal that mechanically engages with and electrically connects to the equipment-side power terminal, the second battery cells are cylindrical in shape, the second battery cells are tab-type battery cells, the rated voltage of the second battery pack is in the range of 9.72 [V] - 11.88 [V], and the plate thickness of the second battery-side power terminal is in the range of 0.30 [mm] - 0.59 [mm] or in the range of 0.30 [mm] - 0.64 [mm]. (Item A2) The electrical equipment system of Item A1, wherein the ratio of the weight of the first battery pack to the weight of the second battery pack is in the range of 0.9 - 1.1. (Item A3) An electrical equipment system of item A1 or A2, wherein the rated capacity of the first battery pack is in the range of 2.0 [Ah] to 12.0 [Ah], and the rated capacity of the second battery pack is in the range of 2.0 [Ah] to 12.0 [Ah]. (Item A4) An electrical equipment system of any one of items A1 to A3, wherein the first battery pack is a stick-type battery pack, and the second battery pack is a stick-type battery pack.(Item A5) An electrical equipment system according to any one of items A1 to A3, wherein the first battery pack is a slide-type battery pack, and the second battery pack is a slide-type battery pack. (Item A6) An electrical equipment system according to any one of items A1 to A5, wherein the diameter of the first battery cell is in the range of 17 [mm] - 23 [mm], and the diameter of the second battery cell is in the range of 17 [mm] - 23 [mm]. (Item A7) An electrical equipment system according to any one of items A1 to A6, wherein the height of the first battery cell is in the range of 64 [mm] - 72 [mm], and the height of the second battery cell is in the range of 64 [mm] - 72 [mm]. (Item A8) An electrical equipment system according to any one of items A1 to A7, wherein the conductivity of the first battery-side power terminal is in the range of 31 [%IACS] - 106 [%IACS], and the conductivity of the second battery-side power terminal is in the range of 1 [%IACS] - 30 [%IACS]. (Item A9) An electrical equipment system according to any one of items A1 to A8, wherein the DC internal resistance of the first battery cell is in the range of 2.5 [mΩ] - 20 [mΩ], and the DC internal resistance of the second battery cell is in the range of 21 [mΩ] - 100 [mΩ]. (Item A10) An electrical equipment system according to any one of items A1 to A8, wherein the DC internal resistance of the first battery cell is in the range of 5 [mΩ] - 20 [mΩ], and the DC internal resistance of the second battery cell is in the range of 21 [mΩ] - 50 [mΩ]. (Item A11) An electrical equipment system according to any one of items A1 to A10, wherein the height of the first battery-side power terminal is in the range of 8.6 [mm] - 15.0 [mm], and the height of the second battery-side power terminal is in the range of 3.0 [mm] - 8.5 [mm]. (Item A12) An electrical equipment system according to any one of items A1 to A11, wherein the first battery pack comprises a first lead plate joined to the positive or negative cell terminal of the first battery cell, the thickness of the first lead plate is in the range of 0.31 [mm] - 1.0 [mm], and the second battery pack comprises a second lead plate joined to the positive or negative cell terminal of the second battery cell, the thickness of the second lead plate is in the range of 0.1 [mm] - 0.3 [mm].(Item A13) The electrical equipment system of Item A12, wherein the first lead plate is joined to the positive or negative cell terminal of the first battery cell by laser welding or spot welding, and the second lead plate is joined to the positive or negative cell terminal of the second battery cell by spot welding.

[0296] (Item B1) A battery pack that is detachable from the battery pack mounting portion of an electrical device, wherein the battery pack mounting portion is equipped with a device-side power terminal for charging or discharging power between the electrical device and the battery pack, the battery pack comprises three battery cells electrically connected in series and a battery-side power terminal that mechanically engages with and electrically connects to the device-side power terminal, the battery cells are cylindrical in shape, the battery cells are of the tablet type, the rated voltage of the battery pack is in the range of 9.72 [V] to 11.88 [V], and the plate thickness of the battery-side power terminal is in the range of 0.30 [mm] to 1.00 [mm]. (Item B2) The battery pack of Item B1, wherein the weight of the battery pack is in the range of 150 [g] to 630 [g]. (Item B3) The battery pack of Item B1 or B2, wherein the rated capacity of the battery pack is in the range of 2.0 [Ah] to 12.0 [Ah]. (Item B4) The battery pack is a stick-type battery pack, according to any one of items B1 to B3. (Item B5) The battery pack is a slide-type battery pack, according to any one of items B1 to B3. (Item B6) The height of the battery cell is in the range of 64 [mm] - 72 [mm], according to any one of items B1 to B5. (Item B7) The rated capacity of the battery cell is in the range of 2.0 [Ah] - 6.0 [Ah], according to any one of items B1 to B6. (Item B8) The conductivity of the battery-side power terminal is in the range of 31 [%IACS] - 106 [%IACS], according to any one of items B1 to B7. (Item B9) A battery pack according to any one of items B1 to B8, wherein the DC internal resistance of the battery cell is in the range of 2.5 [mΩ] to 20 [mΩ]. (Item B10) A battery pack according to any one of items B1 to B8, wherein the DC internal resistance of the battery cell is in the range of 5 [mΩ] to 20 [mΩ]. (Item B11) A battery pack according to any one of items B1 to B10, wherein the height of the battery-side power terminal is in the range of 8.6 [mm] to 15.0 [mm].(Item B12) The battery pack according to any one of items B1 to B11, wherein the battery pack comprises a lead plate joined to the positive or negative cell terminal of the battery cell, and the thickness of the lead plate is in the range of 0.31 [mm] - 1.0 [mm]. (Item B13) The battery pack according to item B12, wherein the lead plate is joined to the positive or negative cell terminal of the battery cell by laser welding or spot welding.

[0297] (Item C1) An electrical equipment system comprising a first battery pack, a second battery pack, and an electrical device, wherein the electrical device is provided with a battery pack mounting portion to which the first battery pack or the second battery pack can be selectively attached or detached, the battery pack mounting portion is provided with an equipment-side power terminal for charging or discharging power between the electrical device and the first battery pack or the second battery pack, the first battery pack comprises three first battery cells electrically connected in series, and a first battery-side power terminal that mechanically engages with and electrically connects to the equipment-side power terminal, the first battery cells are cylindrical in shape, the first battery cells are tablet-type battery cells, the rated voltage of the first battery pack is in the range of 9.72 [V] - 11.88 [V], and the height of the first battery-side power terminal is in the range of 8.6 [mm] - 15.0 [mm]. An electrical equipment system, wherein the second battery pack comprises three second battery cells electrically connected in series and a second battery-side power terminal that mechanically engages with and electrically connects to the equipment-side power terminal, the second battery cells are cylindrical in shape, the second battery cells are tab-type battery cells, the rated voltage of the second battery pack is in the range of 9.72 [V] to 11.88 [V], and the height of the second battery-side power terminal is in the range of 3.0 [mm] to 8.5 [mm]. (Item C2) The electrical equipment system of Item C1, wherein the ratio of the weight of the first battery pack to the weight of the second battery pack is in the range of 0.9 to 1.1. (Item C3) The electrical equipment system of Item C1 or C2, wherein the first battery pack is a stick-type battery pack, and the second battery pack is a stick-type battery pack. (Item C4) An electrical equipment system according to any one of items C1 to C3, wherein the diameter of the first battery cell is in the range of 17 [mm] to 20 [mm], and the diameter of the second battery cell is in the range of 17 [mm] to 20 [mm]. (Item C5) An electrical equipment system according to any one of items C1 to C4, wherein the height of the first battery cell is in the range of 64 [mm] to 72 [mm], and the height of the second battery cell is in the range of 64 [mm] to 72 [mm].(Item C6) An electrical equipment system according to any one of items C1 to C4, wherein the height of the first battery cell is in the range of 64 [mm] - 67 [mm] and the height of the second battery cell is in the range of 64 [mm] - 67 [mm]. (Item C7) An electrical equipment system according to any one of items C1 to C6, wherein the conductivity of the first battery-side power terminal is in the range of 31 [%IACS] - 106 [%IACS] and the conductivity of the second battery-side power terminal is in the range of 1 [%IACS] - 30 [%IACS]. (Item C8) An electrical equipment system according to any one of items C1 to C7, wherein the DC internal resistance of the first battery cell is in the range of 2.5 [mΩ] - 20 [mΩ] and the DC internal resistance of the second battery cell is in the range of 21 [mΩ] - 100 [mΩ]. (Item C9) An electrical equipment system according to any one of items C1 to C8, wherein the DC internal resistance of the first battery cell is in the range of 5 [mΩ] - 20 [mΩ], and the DC internal resistance of the second battery cell is in the range of 21 [mΩ] - 50 [mΩ]. (Item C10) An electrical equipment system according to any one of items C1 to C9, wherein the plate thickness of the first battery-side power terminal is in the range of 0.60 [mm] - 1.00 [mm], or in the range of 0.65 [mm] - 1.00 [mm], and the plate thickness of the second battery-side power terminal is in the range of 0.30 [mm] - 0.59 [mm], or in the range of 0.30 [mm] - 0.64 [mm]. (Item C11) An electrical equipment system according to any one of items C1 to C10, wherein the overall length of the first battery pack is in the range of 83.0 [mm] to 92.0 [mm], the overall width of the first battery pack is in the range of 62.0 [mm] to 69.0 [mm], the overall length of the second battery pack is in the range of 83.0 [mm] to 92.0 [mm], and the overall width of the second battery pack is in the range of 62.0 [mm] to 69.0 [mm].(Item C12) An electrical equipment system according to any one of items C1 to C11, wherein the first battery pack comprises a first lead plate joined to the positive or negative cell terminal of the first battery cell, the thickness of the first lead plate being in the range of 0.31 [mm] to 1.0 [mm], and the second battery pack comprises a second lead plate joined to the positive or negative cell terminal of the second battery cell, the thickness of the second lead plate being in the range of 0.1 [mm] to 0.3 [mm]. (Item C13) An electrical equipment system according to item C12, wherein the first lead plate is joined to the positive or negative cell terminal of the first battery cell by laser welding or spot welding, and the second lead plate is joined to the positive or negative cell terminal of the second battery cell by spot welding.

[0298] (Item D1) A battery pack that is detachable from the battery pack mounting section of an electrical device, wherein the battery pack mounting section is equipped with a device-side power terminal for charging or discharging power between the electrical device and the battery pack, the battery pack comprises three battery cells electrically connected in series and a battery-side power terminal that mechanically engages with and electrically connects to the device-side power terminal, the battery cells are cylindrical in shape, the battery cells are of the tablet type, the rated voltage of the battery pack is in the range of 9.72 [V] to 11.88 [V], and the height of the battery-side power terminal is in the range of 3.0 [mm] to 15.0 [mm]. (Item D2) The battery pack of Item D1, wherein the weight of the battery pack is in the range of 150 [g] to 630 [g]. (Item D3) The battery pack of Item D1 or D2, wherein the battery pack is a stick-type battery pack. (Item D4) A battery pack according to any one of items D1 to D3, wherein the diameter of the battery cell is in the range of 17 [mm] - 20 [mm]. (Item D5) A battery pack according to any one of items D1 to D4, wherein the height of the battery cell is in the range of 64 [mm] - 72 [mm]. (Item D6) A battery pack according to any one of items D1 to D4, wherein the height of the battery cell is in the range of 64 [mm] - 67 [mm]. (Item D7) A battery pack according to any one of items D1 to D6, further comprising three more battery cells electrically connected in series and an insertion projection inserted into the battery pack mounting portion, wherein the three battery cells are arranged inside the insertion projection, and the three further battery cells are arranged outside the insertion projection, and the longitudinal direction of the three battery cells and the longitudinal direction of the three further battery cells are substantially perpendicular to each other. (Item D8) A battery pack according to any one of items D1 to D7, wherein the conductivity of the battery-side power terminal is in the range of 31 [% IACS] - 106 [% IACS]. (Item D9) A battery pack according to any one of items D1 to D8, wherein the plate thickness of the battery-side power terminal is in the range of 0.30 [mm] - 1.00 [mm].(Item D10) A battery pack according to any one of items D1 to D9, wherein the overall length of the battery pack is in the range of 83.0 [mm] - 92.0 [mm], and the overall width of the battery pack is in the range of 62.0 [mm] - 69.0 [mm]. (Item D11) A battery pack according to any one of items D1 to D10, wherein the battery pack comprises a lead plate joined to the positive or negative cell terminal of the battery cell, and the thickness of the lead plate is in the range of 0.31 [mm] - 1.0 [mm]. (Item D12) The battery pack according to item D11, wherein the lead plate is joined to the positive or negative cell terminal of the battery cell by laser welding or spot welding.

[0299] (Item E1) An electrical equipment system comprising a first battery pack, a second battery pack, and an electrical device, wherein the electrical device includes a battery pack mounting section to which the first battery pack or the second battery pack can be selectively attached or detached, the first battery pack comprises three first battery cells electrically connected in series and a first lead plate joined to the positive or negative cell terminal of the first battery cell, the first battery cell has a cylindrical shape, the first battery cell is a tablet-type battery cell, the rated voltage of the first battery pack is in the range of 9.72 [V] - 11.88 [V], the thickness of the first lead plate is in the range of 0.31 [mm] - 1.0 [mm], the second battery pack comprises three second battery cells electrically connected in series and a second lead plate joined to the positive or negative cell terminal of the second battery cell, the second battery cell has a cylindrical shape, An electrical equipment system in which the second battery cell is a tab-type battery cell, the rated voltage of the second battery pack is in the range of 9.72 [V] - 11.88 [V], and the thickness of the second lead plate is in the range of 0.1 [mm] - 0.3 [mm]. (Item E2) The electrical equipment system of Item E1 in which the conductivity of the first lead plate is in the range of 31 [%IACS] - 106 [%IACS], and the conductivity of the second lead plate is in the range of 1 [%IACS] - 30 [%IACS]. (Item E3) The electrical equipment system of Item E1 or E2 in which the ratio of the weight of the first battery pack to the weight of the second battery pack is in the range of 0.9 - 1.1. (Item E4) The electrical equipment system of any one of Items E1 to E3 in which the first battery pack is a stick-type battery pack, and the second battery pack is a stick-type battery pack. (Item E5) An electrical equipment system according to any one of items E1 to E4, wherein the diameter of the first battery cell is in the range of 17 [mm] to 20 [mm], and the diameter of the second battery cell is in the range of 17 [mm] to 20 [mm].(Item E6) An electrical equipment system according to any one of items E1 to E5, wherein the height of the first battery cell is in the range of 64 [mm] - 72 [mm] and the height of the second battery cell is in the range of 64 [mm] - 72 [mm]. (Item E7) An electrical equipment system according to any one of items E1 to E5, wherein the height of the first battery cell is in the range of 64 [mm] - 67 [mm] and the height of the second battery cell is in the range of 64 [mm] - 67 [mm]. (Item E8) An electrical equipment system according to any one of items E1 to E7, wherein the conductivity of the first battery-side power terminal is in the range of 31 [%IACS] - 106 [%IACS] and the conductivity of the second battery-side power terminal is in the range of 1 [%IACS] - 30 [%IACS].

[0300] (Item F1) A battery pack that is detachable from the battery pack mounting section of an electrical device, wherein the battery pack comprises three battery cells electrically connected in series and a lead plate joined to the positive or negative cell terminal of the battery cells, the battery cells are cylindrical in shape, the battery cells are of the tablet type, the rated voltage of the battery pack is in the range of 9.72 [V] to 11.88 [V], and the thickness of the lead plate is in the range of 0.31 [mm] to 1.0 [mm]. (Item F2) The battery pack of Item F1, wherein the conductivity of the lead plate is in the range of 31 [%IACS] to 106 [%IACS]. (Item F3) The battery pack of Item F1 or F2, wherein the weight of the battery pack is in the range of 150 [g] to 630 [g]. (Item F4) The battery pack is a stick-type battery pack, according to any one of items F1 to F3. (Item F5) The battery pack is one of items F1 to F4, with a battery cell diameter in the range of 17 mm to 20 mm. (Item F6) The battery pack is one of items F1 to F5, with a first battery cell height in the range of 64 mm to 67 mm, and a second battery cell height in the range of 64 mm to 67 mm. (Item F7) The battery pack is one of items F1 to F5, with a first battery cell height in the range of 64 mm to 72 mm, and a second battery cell height in the range of 64 mm to 72 mm.(Item F8) The battery pack according to any one of items F1 to F7, wherein the first battery pack further comprises three more first battery cells electrically connected in series, the three first battery cells are located inside the first insertion projection, the three further first battery cells are located outside the first insertion projection, the longitudinal direction of the three first battery cells is substantially perpendicular to the longitudinal direction of the three further first battery cells, the second battery pack further comprises three more second battery cells electrically connected in series, the three second battery cells are located inside the second insertion projection, the three further second battery cells are located outside the second insertion projection, and the longitudinal direction of the three second battery cells is substantially perpendicular to the longitudinal direction of the three further second battery cells. (Item F9) A battery pack according to any one of items F1 to F8, wherein the conductivity of the battery-side power terminals is within the range of 31 [%IACS] - 106 [%IACS].

[0301] (Item G1) An electrical equipment system comprising a first battery pack, a second battery pack, and an electrical device, wherein the electrical device includes a battery pack mounting section to which the first battery pack or the second battery pack can be selectively attached or detached, the first battery pack comprises three first battery cells electrically connected in series, and a first lead plate joined to the positive or negative cell terminal of the first battery cell, the first battery cell has a cylindrical shape, the first battery cell is a tablet-type battery cell, the rated voltage of the first battery pack is in the range of 9.72 [V] - 11.88 [V], the first lead plate is joined to the positive or negative cell terminal of the first battery cell by laser welding or spot welding, the second battery pack comprises three second battery cells electrically connected in series, and a second lead plate joined to the positive or negative cell terminal of the second battery cell, the second battery cell has a cylindrical shape, An electrical equipment system, wherein the second battery cell is a tab-type battery cell, the rated voltage of the second battery pack is in the range of 9.72 [V] - 11.88 [V], and the second lead plate is joined to the positive or negative cell terminal of the second battery cell by spot welding. (Item G2) The electrical equipment system of Item G1, wherein the thickness of the first lead plate is in the range of 0.31 [mm] - 1.0 [mm], and the thickness of the second lead plate is in the range of 0.1 [mm] - 0.3 [mm]. (Item G3) The electrical equipment system of Item G1 or G2, wherein the ratio of the weight of the first battery pack to the weight of the second battery pack is in the range of 0.9 - 1.1. (Item G4) The electrical equipment system of any one of Items G1 to G3, wherein the first battery pack is a stick-type battery pack, and the second battery pack is a stick-type battery pack. (Item G5) An electrical equipment system according to any one of items G1 to G4, wherein the diameter of the first battery cell is in the range of 17 [mm] to 20 [mm], and the diameter of the second battery cell is in the range of 17 [mm] to 20 [mm].(Item G6) An electrical equipment system according to any one of items G1 to G5, wherein the height of the first battery cell is in the range of 64 [mm] - 72 [mm] and the height of the second battery cell is in the range of 64 [mm] - 72 [mm]. (Item G7) An electrical equipment system according to any one of items G1 to G5, wherein the height of the first battery cell is in the range of 64 [mm] - 67 [mm] and the height of the second battery cell is in the range of 64 [mm] - 67 [mm]. (Item G8) An electrical equipment system according to any one of items G1 to G7, wherein the conductivity of the first battery-side power terminal is in the range of 31 [%IACS] - 106 [%IACS] and the conductivity of the second battery-side power terminal is in the range of 1 [%IACS] - 30 [%IACS].

[0302] (Item H1) A battery pack that is detachable from the battery pack mounting section of an electrical device, wherein the battery pack comprises three battery cells electrically connected in series and a lead plate joined to the positive or negative cell terminal of the battery cells, the battery cells are cylindrical in shape, the battery cells are of the tablet type, the rated voltage of the battery pack is in the range of 9.72 [V] to 11.88 [V], and the lead plate is joined to the positive or negative cell terminal of the battery cells by laser welding or spot welding. (Item H2) The battery pack of Item H1, wherein the thickness of the lead plate is in the range of 0.31 [mm] to 1.0 [mm]. (Item H3) The battery pack of Item H1 or H2, wherein the weight of the battery pack is in the range of 150 [g] to 630 [g]. (Item H4) The battery pack is a stick-type battery pack, according to any one of items H1 to H3. (Item H5) The battery pack is one of items H1 to H4, with a battery cell diameter in the range of 17 mm to 20 mm. (Item H6) The battery pack is one of items H1 to H5, with a first battery cell height in the range of 64 mm to 67 mm, and a second battery cell height in the range of 64 mm to 67 mm. (Item H7) The battery pack is one of items H1 to H5, with a first battery cell height in the range of 64 mm to 72 mm, and a second battery cell height in the range of 64 mm to 72 mm.(Item H8) The battery pack according to any one of items H1 to H7, wherein the first battery pack further comprises three more first battery cells electrically connected in series, the three first battery cells are located inside the first insertion projection, the three further first battery cells are located outside the first insertion projection, the longitudinal direction of the three first battery cells and the longitudinal direction of the three further first battery cells are substantially perpendicular, the second battery pack further comprises three more second battery cells electrically connected in series, the three second battery cells are located inside the second insertion projection, the three further second battery cells are located outside the second insertion projection, and the longitudinal direction of the three second battery cells and the longitudinal direction of the three further second battery cells are substantially perpendicular. (Item H9) A battery pack according to any one of items H1 to H8, wherein the conductivity of the battery-side power terminals is within the range of 31 [%IACS] - 106 [%IACS].

[0303] (Item I1) An electrical equipment system comprising a first battery pack, a second battery pack, and an electrical device, wherein the electrical device is equipped with a battery pack mounting section to which the first battery pack or the second battery pack can be selectively attached or detached, the first battery pack is a stick-type battery pack, the first battery pack comprises three first battery cells electrically connected in series, and a first insertion projection that is inserted into the battery pack mounting section, when the direction in which the first battery pack is inserted into the battery pack mounting section is upward, the first insertion projection comprises a first primary tip surface located at the upper end and a first secondary tip surface located below the first primary tip surface, the first battery cells have a cylindrical shape, the first battery cells are tablet-type battery cells, the rated voltage of the first battery pack is in the range of 9.72 [V] - 11.88 [V], and the overall length of the first battery pack is in the range of 83.0 [mm] - 92.0 [mm]. The overall width of the first battery pack is in the range of 62.0 [mm] - 69.0 [mm], the height from the bottom surface of the first battery pack to the first primary tip surface is in the range of 105 [mm] - 116 [mm], the height from the bottom surface of the first battery pack to the first secondary tip surface is in the range of 96 [mm] - 107 [mm], the second battery pack is a stick-type battery pack, the second battery pack comprises three second battery cells electrically connected in series and a second insertion projection that is inserted into the battery pack mounting portion, when the direction in which the second battery pack is inserted into the battery pack mounting portion is upward, the second insertion projection comprises a second primary tip surface located at the upper end and a second secondary tip surface located below the second primary tip surface, the second battery cell has a cylindrical shape, the second battery cell is a tab-type battery cell, The rated voltage of the second battery pack is in the range of 9.72 [V] to 11.88 [V], the overall length of the second battery pack is in the range of 83.0 [mm] to 92.0 [mm], and the overall width of the second battery pack is in the range of 62.0 [mm] to 69.0 [mm].An electrical equipment system in which the height from the bottom surface of the second battery pack to the first primary tip surface is in the range of 105 [mm] - 116 [mm], and the height from the bottom surface of the second battery pack to the first secondary tip surface is in the range of 96 [mm] - 107 [mm]. (Item I2) The battery pack of Item I1, in which the weight of the first battery pack is in the range of 150 [g] - 630 [g], and the weight of the second battery pack is in the range of 150 [g] - 630 [g]. (Item I3) The battery pack of Item I2, in which the weight of the first battery pack is in the range of 370 [g] - 500 [g] or in the range of 330 [g] - 480 [g], and the weight of the second battery pack is in the range of 370 [g] - 500 [g] or in the range of 330 [g] - 480 [g]. (Item I4) An electrical equipment system according to any one of items I1 to I3, wherein the ratio of the weight of the first battery pack to the weight of the second battery pack is in the range of 0.9 to 1.1. (Item I5) An electrical equipment system according to any one of items I1 to I4, wherein the rated capacity of the first battery pack is in the range of 4.0 [Ah] to 8.0 [Ah], and the rated capacity of the second battery pack is in the range of 4.0 [Ah] to 8.0 [Ah]. (Item I6) An electrical equipment system according to any one of items I1 to I5, wherein the diameter of the first battery cell is in the range of 17 [mm] to 20 [mm], and the diameter of the second battery cell is in the range of 17 [mm] to 20 [mm]. (Item I7) An electrical equipment system according to any one of items I1 to I6, wherein the height of the first battery cell is in the range of 64 [mm] - 67 [mm], and the height of the second battery cell is in the range of 64 [mm] - 67 [mm]. (Item I8) An electrical equipment system according to any one of items I1 to I7, wherein the first battery pack further comprises three more first battery cells electrically connected in series, and the second battery pack further comprises three more second battery cells electrically connected in series. (Item I9) An electrical equipment system according to any one of items I1 to I8, wherein the rated capacity of the first battery cell is in the range of 2.0 [Ah] - 6.0 [Ah], and the rated capacity of the second battery cell is in the range of 2.0 [Ah] - 6.0 [Ah]. (Item I10)An electrical equipment system according to any one of items I1 to I9, wherein the weight of the first battery cell is in the range of 45 g to 50 g, and the weight of the second battery cell is in the range of 45 g to 50 g. (Item I11) An electrical equipment system according to any one of items I1 to I10, wherein the three first battery cells are arranged inside the first insertion protrusion, the three further first battery cells are arranged outside the first insertion protrusion, the longitudinal directions of the three first battery cells and the longitudinal directions of the three further first battery cells are substantially perpendicular, the three second battery cells are arranged inside the second insertion protrusion, the three further second battery cells are arranged outside the second insertion protrusion, and the longitudinal directions of the three second battery cells and the longitudinal directions of the three further second battery cells are substantially perpendicular. (Item I12) An electrical equipment system according to any one of items I1 to I11, wherein the DC internal resistance of the first battery cell is in the range of 2.5 [mΩ] to 20 [mΩ], and the DC internal resistance of the second battery cell is in the range of 21 [mΩ] to 100 [mΩ]. (Item I13) An electrical equipment system according to any one of items I1 to I11, wherein the DC internal resistance of the first battery cell is in the range of 5 [mΩ] to 20 [mΩ], and the DC internal resistance of the second battery cell is in the range of 21 [mΩ] to 50 [mΩ]. (Item I14) An electrical equipment system according to any one of items I1 to I13, wherein the battery pack mounting portion is provided with equipment-side power terminals for charging or discharging power between the electrical equipment and the first battery pack or the second battery pack, the first battery pack further comprises a first battery-side power terminal that mechanically engages with and is electrically connected to the equipment-side power terminal, the plate thickness of the first battery-side power terminal is in the range of 0.60 [mm] - 1.00 [mm] or in the range of 0.65 [mm] - 1.00 [mm], the second battery pack further comprises a second battery-side power terminal that mechanically engages with and is electrically connected to the equipment-side power terminal, the plate thickness of the second battery-side power terminal is in the range of 0.30 [mm] - 0.59 [mm] or in the range of 0.30 [mm] - 0.64 [mm]. (Item I15)An electrical equipment system according to any one of items I1 to I14, wherein the height of the first battery-side power terminal is in the range of 8.6 [mm] to 15.0 [mm], and the height of the second battery-side power terminal is in the range of 3.0 [mm] to 8.5 [mm]. (Item I16) An electrical equipment system according to any one of items I1 to I15, wherein the continuous discharge output per unit mass of the first battery cell is in the range of 2.5 [W / g] to 6.7 [W / g], and the continuous discharge output per unit mass of the second battery cell is in the range of 0.4 [W / g] to 2.5 [W / g]. (Item I17) An electrical equipment system according to any one of items I1 to I15, wherein the continuous discharge output per unit mass of the first battery cell is in the range of 2.5 [W / g] to 5.5 [W / g], and the continuous discharge output per unit mass of the second battery cell is in the range of 1.0 [W / g] to 2.5 [W / g]. (Item I18) An electrical equipment system according to any one of items I1 to I17, wherein the continuous discharge output per unit mass of the first battery pack is in the range of 1.5 [W / g] to 5.3 [W / g], and the continuous discharge output per unit mass of the second battery pack is in the range of 0.2 [W / g] to 1.5 [W / g]. (Item I19) An electrical equipment system according to any one of items I1 to I18, wherein the continuous discharge output per unit mass of the first battery pack is in the range of 1.8 [W / g] to 4.0 [W / g], and the continuous discharge output per unit mass of the second battery pack is in the range of 0.75 [W / g] to 1.8 [W / g].

[0304] (Item J1) A battery pack that is detachable from the battery pack mounting section of an electrical device, wherein the battery pack is a stick-type battery pack, the battery pack comprises three battery cells electrically connected in series and an insertion projection that is inserted into the battery pack mounting section, when the direction in which the battery pack is inserted into the battery pack mounting section is upward, the insertion projection comprises a primary tip surface located at the upper end and a secondary tip surface located below the primary tip surface, the battery cells have a cylindrical shape, the battery cells are tablet-type battery cells, the rated voltage of the battery pack is in the range of 9.72 [V] - 11.88 [V], the overall length of the battery pack is in the range of 83.0 [mm] - 92.0 [mm], the overall width of the battery pack is in the range of 62.0 [mm] - 69.0 [mm], and the height from the bottom surface of the battery pack to the primary tip surface is in the range of 105 [mm] - 116 [mm]. A battery pack in which the height from the bottom surface to the secondary front surface is within the range of 96 mm to 107 mm.

[0305] (Item K1) An electrical equipment system comprising a first battery pack, a second battery pack, and an electrical device, wherein the electrical device is equipped with a battery pack mounting section to which the first battery pack or the second battery pack can be selectively attached or detached, the first battery pack comprises three first battery cells electrically connected in series, the first battery cells have a cylindrical shape, the first battery cells are tabless type battery cells, the rated voltage of the first battery pack is in the range of 9.72 [V] - 11.88 [V], the continuous discharge output per unit mass of the first battery cells is in the range of 2.5 [W / g] - 6.7 [W / g], the second battery pack comprises three second battery cells electrically connected in series, the second battery cells have a cylindrical shape, the second battery cells are tab type battery cells, the rated voltage of the second battery pack is in the range of 9.72 [V] - 11.88 [V], An electrical equipment system in which the continuous discharge output per unit mass of the second battery cell is in the range of 0.4 [W / g] to 2.5 [W / g]. (Item K2) An electrical equipment system comprising a first battery pack, a second battery pack, and an electrical device, wherein the electrical device is equipped with a battery pack mounting section to which the first battery pack or the second battery pack can be selectively attached or detached, the first battery pack comprises three first battery cells electrically connected in series, the first battery cells have a cylindrical shape, the first battery cells are tabless type battery cells, the rated voltage of the first battery pack is in the range of 9.72 [V] - 11.88 [V], the continuous discharge output per unit mass of the first battery cells is in the range of 2.5 [W / g] - 5.5 [W / g], the second battery pack comprises three second battery cells electrically connected in series, the second battery cells have a cylindrical shape, the second battery cells are tab type battery cells, the rated voltage of the second battery pack is in the range of 9.72 [V] - 11.88 [V], An electrical equipment system in which the continuous discharge output per unit mass of the second battery cell is in the range of 1.0 [W / g] to 2.5 [W / g].(Item K3) An electrical equipment system of item K1 or K2, wherein the rated capacity of the first battery pack is in the range of 2.0 [Ah] - 12.0 [Ah], and the rated capacity of the second battery pack is in the range of 2.0 [Ah] - 12.0 [Ah]. (Item K4) An electrical equipment system of any one of items K1 to K3, wherein the first battery pack is a stick-type battery pack, and the second battery pack is a stick-type battery pack. (Item K5) An electrical equipment system of any one of items K1 to K4, wherein the first battery pack is a slide-type battery pack, and the second battery pack is a slide-type battery pack. (Item K6) An electrical equipment system of any one of items K1 to K5, wherein the diameter of the first battery cell is in the range of 17 [mm] - 23 [mm], and the diameter of the second battery cell is in the range of 17 [mm] - 23 [mm]. (Item K7) An electrical equipment system according to any one of items K1 to K6, wherein the DC internal resistance of the first battery cell is in the range of 2.5 [mΩ] to 20 [mΩ], and the DC internal resistance of the second battery cell is in the range of 21 [mΩ] to 100 [mΩ]. (Item K8) An electrical equipment system according to any one of items K1 to K7, wherein the DC internal resistance of the first battery cell is in the range of 5 [mΩ] to 20 [mΩ], and the DC internal resistance of the second battery cell is in the range of 21 [mΩ] to 50 [mΩ].

[0306] (Item L1) A battery pack that is detachable from the battery pack mounting section of an electrical device, wherein the battery pack comprises three battery cells electrically connected in series, the battery cells are cylindrical in shape, the battery cells are of the tablet type, the rated voltage of the battery pack is in the range of 9.72 [V] - 11.88 [V], and the continuous discharge output per unit mass of the battery cells is in the range of 2.0 [W / g] - 6.7 [W / g]. (Item L2) A battery pack that is detachable from the battery pack mounting section of an electrical device, wherein the battery pack comprises three battery cells electrically connected in series, the battery cells are cylindrical in shape, the battery cells are of the tablet type, the rated voltage of the battery pack is in the range of 9.72 [V] - 11.88 [V], and the continuous discharge output per unit mass of the battery cells is in the range of 2.0 [W / g] - 5.5 [W / g]. (Item L3) A battery pack according to item L1 or L2, wherein the rated capacity of the battery pack is in the range of 2.0 [Ah] - 12.0 [Ah]. (Item L4) A battery pack according to any one of items L1 to L3, wherein the battery pack is a stick-type battery pack. (Item L5) A battery pack according to any one of items L1 to L3, wherein the battery pack is a slide-type battery pack. (Item L6) A battery pack according to any one of items L1 to L5, wherein the diameter of the battery cell is in the range of 17 [mm] - 23 [mm]. (Item L7) A battery pack according to any one of items L1 to L6, wherein the DC internal resistance of the battery cell is in the range of 2.5 [mΩ] - 20 [mΩ]. (Item L8) A battery pack according to any one of items L1 to L7, wherein the DC internal resistance of the battery cell is in the range of 5 [mΩ] - 20 [mΩ].

[0307] (Item M1) An electrical equipment system comprising a first battery pack, a second battery pack, and an electrical device, wherein the electrical device is equipped with a battery pack mounting section that allows for selective attachment and detachment of the first battery pack or the second battery pack, the first battery pack comprises a first battery cell, the first battery cell has a cylindrical shape, the first battery cell is a tabless type battery cell, the energy capacity of the first battery pack is less than 72 [Wh], the continuous discharge output per unit mass of the first battery cell is in the range of 2.5 [W / g] to 6.7 [W / g], the second battery pack comprises a second battery cell, the second battery cell has a cylindrical shape, the second battery cell is a tab type battery cell, and the energy capacity of the second battery pack is less than 72 [Wh]. An electrical equipment system in which the continuous discharge output per unit mass of the second battery cell is in the range of 0.4 [W / g] to 2.5 [W / g]. (Item M2) An electrical equipment system comprising a first battery pack, a second battery pack, and an electrical device, wherein the electrical device is equipped with a battery pack mounting section to which the first battery pack or the second battery pack can be selectively attached or detached, the first battery pack comprises a first battery cell, the first battery cell has a cylindrical shape, the first battery cell is a tabless type battery cell, the energy capacity of the first battery pack is less than 72 [Wh], the continuous discharge output per unit mass of the first battery cell is in the range of 2.5 [W / g] to 5.5 [W / g], the second battery pack comprises a second battery cell, the second battery cell has a cylindrical shape, the second battery cell is a tab type battery cell, and the energy capacity of the second battery pack is less than 72 [Wh]. An electrical equipment system in which the continuous discharge output per unit mass of the second battery cell is in the range of 1.0 [W / g] to 2.5 [W / g]. (Item M3) The electrical equipment system of Item M1 or M2, wherein the first battery pack comprises three of the first battery cells electrically connected in series, and the second battery pack comprises three of the second battery cells electrically connected in series.(Item M4) The electrical equipment system of Item M3, wherein the number of first battery cells electrically connected in series in the first battery pack is six or less, and the number of second battery cells electrically connected in series in the second battery pack is six or less.

[0308] (Item N1) A battery pack that is detachable from the battery pack mounting section of an electrical device, wherein the battery pack comprises battery cells, the battery cells are cylindrical in shape, the battery cells are of the tablet type, the energy capacity of the battery pack is less than 72 [Wh], and the continuous discharge output per unit mass of the battery cells is in the range of 2.0 [W / g] to 6.7 [W / g]. (Item N2) A battery pack that is detachable from the battery pack mounting section of an electrical device, wherein the battery pack comprises battery cells, the battery cells are cylindrical in shape, the battery cells are of the tablet type, the energy capacity of the battery pack is less than 72 [Wh], and the continuous discharge output per unit mass of the battery cells is in the range of 2.0 [W / g] to 5.5 [W / g]. (Item N3) The battery pack of item N1 or N2, wherein the battery pack comprises three of the battery cells electrically connected in series. (Item N4) The battery pack of Item N3, wherein the number of battery cells electrically connected in series in the battery pack is six or less.

[0309] (Item O1) An electrical equipment system comprising a first battery pack, a second battery pack, and an electrical device, wherein the electrical device is equipped with a battery pack mounting section to which the first battery pack or the second battery pack can be selectively attached or detached, the first battery pack comprises a first battery cell, the first battery cell has a cylindrical shape, the first battery cell is a tabless type battery cell, the energy capacity of the first battery pack is 142.56 [Wh] or less, the diameter of the first battery cell is in the range of 17 [mm] to 20 [mm], the continuous discharge output per unit mass of the first battery cell is in the range of 2.5 [W / g] to 6.7 [W / g], the second battery pack comprises a s...

Claims

An electrical equipment system, It is equipped with a first battery pack, a second battery pack, and electrical equipment. The electrical device is equipped with a battery pack mounting section that allows for the selective attachment and detachment of either the first battery pack or the second battery pack. The first battery pack comprises three first battery cells electrically connected in series, The first battery cell has a cylindrical shape, The diameter of the first battery cell is in the range of 17 [mm] - 20 [mm]. The first battery cell is a tablet-type battery cell, The DC internal resistance of the first battery cell is in the range of 5 [mΩ] to 20 [mΩ]. The rated voltage of the first battery pack is in the range of 9.72 [V] - 11.88 [V]. The second battery pack comprises three second battery cells electrically connected in series, The second battery cell has a cylindrical shape, The diameter of the second battery cell is in the range of 17 [mm] - 20 [mm]. The second battery cell is a tab-type battery cell, The DC internal resistance of the second battery cell is in the range of 21 [mΩ] to 50 [mΩ]. An electrical equipment system in which the rated voltage of the second battery pack is in the range of 9.72 [V] - 11.88 [V]. 　 The diameter of the first battery cell is in the range of 17 [mm] - 19 [mm]. The electrical equipment system according to claim 1, wherein the diameter of the second battery cell is in the range of 17 mm to 19 mm. 　 The height of the first battery cell is within the range of 64 [mm] - 67 [mm]. The electrical equipment system according to claim 1 or 2, wherein the height of the second battery cell is in the range of 64 mm to 67 mm. 　 The weight of the first battery cell is in the range of 40 g to 50 g. The electrical equipment system according to any one of claims 1 to 3, wherein the weight of the second battery cell is in the range of 40 g to 50 g. 　 The rated capacity of the first battery cell is in the range of 2.0 [Ah] to 6.0 [Ah]. The electrical equipment system according to any one of claims 1 to 4, wherein the rated capacity of the second battery cell is in the range of 2.0 [Ah] to 6.0 [Ah]. 　 The rated capacity of the first battery pack is in the range of 2.0 [Ah] to 6.0 [Ah]. The electrical equipment system according to any one of claims 1 to 5, wherein the rated capacity of the second battery pack is in the range of 2.0 [Ah] to 6.0 [Ah]. 　 The first battery pack is a slide-type battery pack, The electrical equipment system according to any one of claims 1 to 6, wherein the second battery pack is a slide-type battery pack. 　 The weight of the first battery pack is in the range of 180 g to 270 g. The electrical equipment system according to claim 7, wherein the weight of the second battery pack is in the range of 180 g to 270 g. 　 The first battery pack is a stick-shaped battery pack, The electrical equipment system according to any one of claims 1 to 6, wherein the second battery pack is a stick-type battery pack. 　 The weight of the first battery pack is 150 g - 240 g. The electrical equipment system according to claim 9, wherein the weight of the second battery pack is 150 g - 240 g. 　 The first battery pack further comprises three first battery cells electrically connected in series, The electrical equipment system according to any one of claims 1 to 5, wherein the second battery pack comprises three further second battery cells electrically connected in series. 　 The rated capacity of the first battery pack is in the range of 4.0 [Ah] to 12.0 [Ah]. The electrical equipment system according to claim 11, wherein the rated capacity of the second battery pack is in the range of 4.0 [Ah] to 12.0 [Ah]. 　 The first battery pack is a slide-type battery pack, The electrical equipment system according to claim 11 or 12, wherein the second battery pack is a slide-type battery pack. 　 The weight of the first battery pack is 330 g - 480 g. The electrical equipment system of claim 13, wherein the weight of the second battery pack is 330 g - 480 g. 　 The first battery pack is a stick-shaped battery pack, The electrical equipment system according to claim 11 or 12, wherein the second battery pack is a stick-shaped battery pack. 　 The weight of the first battery pack is in the range of 370 g to 500 g. The electrical equipment system of claim 15, wherein the weight of the second battery pack is in the range of 370 g to 500 g. 　 It is a battery pack, It has three battery cells that are electrically connected in series, The aforementioned battery cell has a cylindrical shape, The diameter of the aforementioned battery cell is within the range of 17 [mm] - 20 [mm]. The aforementioned battery cell is a tablet-type battery cell, The DC internal resistance of the aforementioned battery cell is in the range of 5 [mΩ] to 20 [mΩ]. The battery pack has a rated voltage within the range of 9.72 [V] - 11.88 [V]. 　 An electrical equipment system, It is equipped with a first battery pack, a second battery pack, and electrical equipment. The electrical device is equipped with a battery pack mounting section that allows for the selective attachment and detachment of either the first battery pack or the second battery pack. The first battery pack comprises three first battery cells electrically connected in series, The first battery cell has a cylindrical shape, The diameter of the first battery cell is in the range of 21 [mm] - 23 [mm]. The first battery cell is a tablet-type battery cell, The DC internal resistance of the first battery cell is in the range of 5 [mΩ] - 15 [mΩ]. The rated voltage of the first battery pack is in the range of 9.72 [V] - 11.88 [V]. The second battery pack comprises three second battery cells electrically connected in series, The second battery cell has a cylindrical shape, The diameter of the second battery cell is in the range of 21 [mm] - 23 [mm]. The second battery cell is a tab-type battery cell, The DC internal resistance of the second battery cell is in the range of 16 [mΩ] to 50 [mΩ]. An electrical equipment system in which the rated voltage of the second battery pack is in the range of 9.72 [V] - 11.88 [V]. 　 The diameter of the first battery cell is in the range of 21 [mm] - 22 [mm]. The electrical equipment system of claim 18, wherein the diameter of the second battery cell is in the range of 21 [mm] - 22 [mm]. 　 The height of the first battery cell is within the range of 70 [mm] - 72 [mm]. The electrical equipment system according to claim 18 or 19, wherein the height of the second battery cell is in the range of 70 mm to 72 mm. 　 The weight of the first battery cell is in the range of 65 [g] - 75 [g]. The electrical equipment system according to any one of claims 18 to 20, wherein the weight of the second battery cell is in the range of 65 g to 75 g. 　 The rated capacity of the first battery cell is in the range of 2.0 [Ah] to 6.0 [Ah]. The electrical equipment system according to any one of claims 18 to 21, wherein the rated capacity of the second battery cell is in the range of 2.0 [Ah] to 6.0 [Ah]. 　 The rated capacity of the first battery pack is in the range of 2.0 [Ah] to 6.0 [Ah]. The electrical equipment system according to any one of claims 18 to 22, wherein the rated capacity of the second battery pack is in the range of 2.0 [Ah] to 6.0 [Ah]. 　 The first battery pack is a slide-type battery pack, The electrical equipment system according to any one of claims 18 to 23, wherein the second battery pack is a slide-type battery pack. 　 The weight of the first battery pack is in the range of 270 [g] - 380 [g]. The electrical equipment system of claim 24, wherein the weight of the second battery pack is in the range of 270 g to 380 g. 　 The first battery pack further comprises three first battery cells electrically connected in series, The electrical equipment system according to any one of claims 18 to 22, wherein the second battery pack comprises three further second battery cells electrically connected in series. 　 The rated capacity of the first battery pack is in the range of 4.0 [Ah] to 12.0 [Ah]. The electrical equipment system of claim 26, wherein the rated capacity of the second battery pack is in the range of 4.0 [Ah] to 12.0 [Ah]. 　 The first battery pack is a slide-type battery pack, The electrical equipment system according to claim 26 or 27, wherein the second battery pack is a slide-type battery pack. 　 The weight of the first battery pack is 450 g - 630 g. The electrical equipment system of claim 28, wherein the weight of the second battery pack is 450 g - 630 g. 　 It is a battery pack, It has three battery cells that are electrically connected in series, The aforementioned battery cell has a cylindrical shape, The diameter of the aforementioned battery cell is within the range of 21 [mm] - 23 [mm]. The aforementioned battery cell is a tablet-type battery cell, The DC internal resistance of the aforementioned battery cell is in the range of 5 [mΩ] to 15 [mΩ]. The battery pack has a rated voltage within the range of 9.72 [V] - 11.88 [V].

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