Battery pack

Abstract

A mobile power source having a battery pack including at least two battery cell assemblies each having a frame having a first support member and a second support member, each of the first and second support members including a plurality of cylindrical recesses for receiving the plurality of battery cells for supporting the battery cells. Bus bars are coupled to the first support member via injection molding, each configured to electrically connect to the at least two battery cells. The bus bars include elongated conductors each having a base and fingers extending laterally away from the base. Each of the fingers extends in a first plane and the base extends in a second plane parallel to and offset from the first plane.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 63 / 242,816, filed on September 10, 2021, and Chinese Utility Model Application No. 202222315581.0, filed on September 1, 2022, the entire contents of each of which are incorporated herein by reference.

[0002] TECHNICAL FIELD This disclosure relates to portable power devices, such as battery packs. [Background technology]

[0003] A portable power device, such as a battery pack, may include multiple battery cells. Summary of the Invention [Means for solving the problem]

[0004] The present disclosure provides, in one aspect, a mobile power source including a battery pack having at least two battery pack assemblies. Each battery cell assembly includes a plurality of batteries, each having a first end, a second end opposite the first end, a positive terminal disposed at the first end, and a negative terminal disposed at the first end. Each battery cell assembly also includes a frame having a first support member and a second support member, each of the first and second support members including a plurality of cylindrical recesses that receive the plurality of battery cells for supporting the battery cells. Each battery cell assembly further includes a plurality of bus bars coupled to the first support member and configured to electrically connect to the at least two battery cells. Each bus bar includes an elongated electrical conductor having a base, a plurality of first fingers extending laterally away from the base in a first direction, and a plurality of second fingers extending laterally away from the base in a second direction opposite the first direction. The first finger and second finger extend in a first plane and the base extends in a second plane parallel to and offset from the first plane.

[0005] In some configurations, at least two of the plurality of busbars are positioned adjacent to one another with the first fingers of each of the at least two busbars aligned with one another along the direction of the longitudinal axis of the battery pack. In such configurations, the second fingers of each of the at least two busbars are aligned with one another along the direction of the longitudinal axis of the battery pack. In some configurations, the first fingers and second fingers are alternately positioned along the longitudinal length of the busbars. In some configurations, the plurality of wires connect the first finger of one busbar to the negative terminals of the at least two battery cells and the second finger of at least one busbar to the positive terminals.

[0006] In another aspect, the present disclosure provides a battery pack including at least two battery cell assemblies. Each battery cell assembly includes a plurality of battery cells, each having a first end, a second end opposite the first end, a positive terminal disposed at the first end, and a negative terminal disposed at the first end. Each battery cell assembly also includes a frame having a first support member and a second support member, each of the first and second support members including a plurality of cylindrical recesses that receive the plurality of battery cells for supporting the battery cells. Each battery cell assembly further includes a plurality of bus bars coupled to the first support member. Each bus bar includes an elongated electrical conductor having a base, a plurality of first fingers extending laterally away from the base in a first direction, and a plurality of second fingers extending laterally away from the base in a second direction opposite the first direction. Each battery cell assembly also includes a plurality of wires connecting a first finger of one bus bar to the negative terminals of at least two battery cells and a second finger of at least one bus bar to the positive terminals of at least two different battery cells, the first finger and the second finger extending in a first plane and the base extending in a second plane parallel to and offset from the first plane.

[0007] The present disclosure, in another aspect, provides a mobile power source including a battery pack including at least two battery cell assemblies. Each battery cell assembly includes a plurality of battery cells, each having a first end, a second end opposite the first end, a positive terminal disposed at the first end, and a negative terminal disposed at the first end, a frame having a first support member and a second support member, and a bus bar coupled to the first support member via injection molding and configured to electrically connect to the at least two battery cells. Each of the first and second support members includes a plurality of cylindrical recesses that receive the plurality of battery cells to support the battery cells, and each bus bar includes an elongated conductor having a base and fingers extending laterally away from the base. The fingers extend in a first plane and the base extends in a second plane parallel to and offset from the first plane.

[0008] The present disclosure, in another aspect, provides a mobile power source including a battery pack including at least two battery cell assemblies. Each battery cell assembly includes a plurality of battery cells, each having a first end, a second end opposite the first end, a positive terminal disposed at the first end, and a negative terminal disposed at the first end; a frame having a first support member and a second support member; and a bus bar disposed in each of the plurality of elongated recesses of the first support member and configured to electrically connect to the at least two battery cells. Each of the first and second support members includes a plurality of cylindrical recesses disposed in a vertical row for receiving the plurality of battery cells for supporting the battery cells and the elongated recesses. Each of the elongated recesses is disposed adjacent to at least one row of the plurality of cylindrical recesses. Each of the bus bars includes an elongated conductor having a base and fingers extending laterally away from the base. The base defines the recesses. The fingers extend in a first plane and the base extends in a second plane parallel to and offset from the first plane. A connecting member is disposed within a recess in each base and is integrally formed with the first support member for coupling a corresponding bus bar to the first support member. Wires connect the fingers of each bus bar to either the positive or negative terminal.

[0009] The present disclosure provides, in another aspect, a method of forming a mobile power supply device, the method including forming a frame having a first support member and a second support member, each of the first and second support members being formed from a plastic material and including a plurality of cylindrical recesses arranged in a column for receiving a plurality of battery cells for supporting the battery cells and the elongated recesses, each of the elongated recesses being disposed adjacent to at least one column of the plurality of cylindrical recesses. The method further includes disposing a bus bar in one of the elongated recesses of the first support member, each bus bar including an elongated conductor having a base and fingers extending laterally away from the base. The base defines a recess, the fingers extending in a first plane, and the base extends in a second plane parallel to and offset from the first plane. The method further includes injecting a plastic material into each of the recesses in the base such that the plastic material fills the recesses and forms integral with the first support member, and disposing a plurality of battery cells between the first support member and the second support member such that the plurality of cylindrical recesses in the first support member and the second support member support a plurality of battery cells. Each of the battery cells has a first end, a second end opposite the first end, an anode terminal disposed at the first end, and a cathode terminal disposed at the first end. The method also includes wire bonding a wire between each finger of the bus bar and either the anode terminal or the cathode terminal.

[0010] Other aspects of the disclosure will become apparent by consideration of the detailed description and accompanying drawings. [Brief description of the drawings]

[0011] [Figure 1] FIG. [Diagram 2] FIG. 2 is a perspective view of a battery pack assembly of the power supply device of FIG. 1. [Diagram 3] 3 is a cross-sectional view of the battery pack assembly of FIG. 2 taken along line 3-3 of FIG. 2. [Figure 4] 4 is another cross-sectional view of the battery pack assembly of FIG. 2 taken along line 4-4 of FIG. 2. [Diagram 5] 5 is another cross-sectional view of the battery pack assembly of FIG. 2 taken along line 5-5 of FIG. 2. [Figure 5A] FIG. 3 is a partially exploded perspective view of the battery pack assembly of FIG. 2 with portions removed. [Figure 6-7] FIG. 3 is a perspective view of the battery pack assembly of FIG. 2 with portions removed. [Figure 8-9] 3 is a partially exploded perspective view of a battery cell assembly of the battery pack assembly of FIG. 2. [Figure 10] 3 is a partial perspective view of a battery cell of the battery pack assembly of FIG. 2. [Figure 11] FIG. 9 is a partial side view of the battery cell assembly of FIG. 8. [Figure 12-13] FIG. 11 is a partial perspective view of a bus bar of the battery cell assembly of FIG. [Figure 14] FIG. 9 is an end view of the busbar of the battery cell assembly of FIG. [Figure 15] 15 is a partial cross-sectional view of the battery cell assembly of FIG. 8 taken along line 15-15 of FIG. 11 according to one embodiment. [Figure 16] FIG. 16 is a schematic diagram of two adjacent bus bars according to the embodiment of FIG. 15. [Figure 17] 15 is a partial cross-sectional view of the battery cell assembly of FIG. 8 according to another embodiment, taken along line 15-15 of FIG. 11. [Figure 18] FIG. 18 is a schematic diagram of two adjacent bus bars according to the embodiment of FIG. 17. [Figure 19] 9 is a partial side view of the battery cell assembly of FIG. 8 according to another embodiment. [Figure 20] 9 is a partial side view of the battery cell assembly of FIG. 8 according to another embodiment. [Figure 21] 9 is a partial side view of the battery cell assembly of FIG. 8 according to another embodiment. [Figure 22] 9 is a partial side view of the battery cell assembly of FIG. 8 according to another embodiment. [Figure 23]9 is a partial side view of the battery cell assembly of FIG. 8 according to another embodiment. [Figure 24] 9 is a partial side view of the battery cell assembly of FIG. 8 according to another embodiment. [Diagram 25] 9 is a partial side view of the battery cell assembly of FIG. 8 according to another embodiment. [Figure 26] 9 is a partial side view of the battery cell assembly of FIG. 8 according to another embodiment. [Figure 27] 9 is a partial side view of the battery cell assembly of FIG. 8 according to another embodiment. [Figure 28] 9 is a partial side perspective view of the battery cell assembly of FIG. 8 according to another embodiment. [Figure 29] 9 is a side view of the battery cell assembly of FIG. 8 according to another embodiment, the battery cell assembly including a first support member, a plurality of bus bars, and a voltage sensing PCB. [Diagram 30] FIG. 30 is a perspective side view of the battery cell assembly of FIG. 29 with the voltage sensing PCB removed. [Diagram 31] FIG. 30 is a perspective side view of the battery cell assembly of FIG. 29 with the bus bars and voltage sensing PCB removed. [Diagram 32] 32 is a cross-sectional view of the battery cell assembly of FIG. 29 taken along line 32-32 of FIG. 30. [Diagram 33] 33 is a cross-sectional view of the battery cell assembly of FIG. 29 taken along line 33-33 of FIG. 30. [Diagram 34] 34 is a cross-sectional view of the battery cell assembly of FIG. 29 taken along line 34-34 of FIG. 30. [Diagram 35] 35 is a cross-sectional view of the battery cell assembly of FIG. 29 taken along line 35-35 of FIG. 30. [Diagram 36] FIG. 30 is a perspective view of one of the bus bars of FIG. 29. [Figure 37] FIG. 37 is another perspective view of the bus bar of FIG. [Figure 38] 38 is a cross-sectional view of the bus bar of FIG. 36 taken along line 38-38 of FIG. 36. [Figure 39]39 is a cross-sectional view of the bus bar of FIG. 36 taken along line 39-39 of FIG. 36. [Diagram 40] FIG. 30 is a perspective view of one of the bus bars of FIG. 29. [Diagram 41] FIG. 41 is another perspective view of the bus bar of FIG. [Diagram 42] FIG. 41 is a detailed perspective view of the bus bar of FIG. 40. [Diagram 43] 43 is a cross-sectional view of the bus bar of FIG. 40 taken along line 43-43 of FIG. 40. [Diagram 44] FIG. 30 is a perspective view of one of the bus bars of FIG. 29. [Diagram 45] FIG. 45 is another perspective view of the bus bar of FIG. [Diagram 46] FIG. 45 is a detailed perspective view of the bus bar of FIG. 44. [Figure 47] 47 is a cross-sectional view of the bus bar of FIG. 44 taken along line 47-47 of FIG. 44. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Before any embodiment of the present disclosure is described in detail, it is to be understood that the disclosure is not limited in its application to the details of the embodiments and the arrangement of components set forth in the following description or illustrated in the following drawings. The disclosure is capable of other embodiments and of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

[0013] FIG. 1 illustrates a portable power supply or power supply device 1. The portable power supply device 1 includes a housing 2. In some embodiments, the power supply device 1 includes one or more wheels 3 coupled to the housing 2, and a handle assembly 4 coupled to the housing 2. In the illustrated embodiment, the handle assembly 4 is a telescoping handle movable between an extended position and a folded position. The handle assembly 4 includes an inner tube 5 and an outer tube 6. The inner tube 5 fits closely inside the outer tube 6 and is slidable relative to the outer tube 6. The inner tube 5 is coupled to a horizontal gripping member 7. In some embodiments, the handle assembly 4 further includes a locking mechanism to prevent the inner tube 5 from accidentally moving relative to the outer tube 6. The locking mechanism may include a notch, a sliding catch pin, or another suitable locking mechanism to prevent the inner tube 5 from sliding relative to the outer tube 6 when the handle assembly 4 is in the extended and / or folded position. In practice, a user grasps the gripping member 7 and pulls upward to extend the handle assembly 4. The inner tube 5 slides relative to the outer tube 6 until the handle assembly 4 is locked in the extended position. The user can then pull the power supply 1 by the handle assembly 4 and guide it to the desired location. The wheels 3 of the power supply 1 facilitate such movement.

[0014] The housing 2 of the power supply 1 further includes a power input panel 8, a power output panel 9, and a display 11. In the illustrated embodiment, the power input panel 8 includes a number of electrical connection interfaces configured to accept power from an external power source. In some embodiments, the external power source may be a DC power source, such as a solar cell (e.g., a solar panel), or the power source may be an AC power source, such as a conventional wall outlet. In some embodiments, the power input panel 8 is replaced by or additionally includes a cable configured to plug into a conventional wall outlet. The power accepted by the power input panel 8 may be used to charge an internal power source 10 disposed within the housing 2 of the power supply 1.

[0015] The power output panel 9 includes one or more power outlets. In the illustrated embodiment, the power output panel 9 includes a plurality of AC power outlets 9A and DC power outlets 9B. It should be understood that the number of power outlets included in the power output panel 9 is not limited to the power outlets shown in FIG. 1. For example, in some embodiments of the power supply 1, the power output panel 9 may include more or less power outlets than the power outlets included in the illustrated embodiment of the power supply 1. The power output panel 9 is configured to provide power from the internal power source 10 to one or more peripheral devices. The one or more peripheral devices may be a smartphone, a tablet computer, a laptop computer, a portable music player, a power tool, a power tool battery pack, a power tool battery pack charger, and the like. The peripheral devices may be configured to receive DC and / or AC power from the power output panel 9. In some embodiments, the power supply 1 also includes one or more battery pack charging outlets (not shown) configured to receive one or more battery packs and provide power from the internal power source 10 to the one or more battery packs.

[0016] Display 11 is configured to indicate to a user the status of power supply 1, such as the charging status and / or fault status of internal power source 10. In some embodiments, display 11 includes one or more light emitting diode ("LED") indicators configured to illuminate to indicate the current charging status of internal power source 10. In some embodiments, display 11 is, for example, a liquid crystal display ("LCD"), a light emitting diode ("LED") display, an organic LED ("OLED") display, an electroluminescent display ("ELD"), a surface conduction electron emitter display ("SED"), a field emission display ("FED"), a thin film transistor ("TFT") LCD, or the like. In other embodiments, power supply 1 does not include a display.

[0017] 2-30 illustrate all or part of an internal power source 10 according to several different embodiments. In the following, the internal power source 10 will be referred to as a battery pack assembly 10.

[0018] 2-6, in one embodiment, battery pack assembly 10 includes a housing 14 and a plurality of battery cell assemblies 18 received within the housing 14. In the illustrated embodiment, battery pack assembly 10 includes two battery cell assemblies 18. In other embodiments, battery pack assembly 10 may include one or more battery cell assemblies 18 (e.g., three, four, etc.). The battery pack assembly 10 is configured to be a high power battery pack capable of connecting to and operating a variety of motorized power tools (e.g., cut-off saws, miter saws, table saws, core drills, augers, chippers, jackhammers, compactors, vibrators, crushers, drain cleaners, welders, cable taggers, pumps, etc.), outdoor tools (e.g., chainsaws, brush cutters, hedge trimmers, blowers, lawn mowers, etc.), other motorized equipment (e.g., vehicles, utility carts, material handling carts, etc.), and the like, and non-motorized power equipment (e.g., power sources, lighting, AC / DC adapters, generators, personal electronic devices, etc.), all of which are hereinafter referred to as "equipment" in this specification.

[0019] The housing 14 includes a top surface 22, a bottom surface 26, a first side 30, a second side 34 opposite the first side 30, a first end 38, and a second end 42 opposite the first end 38. In addition, the housing 14 includes a longitudinal axis 46 extending through the first end 38 and the second end 42. A transverse axis 50 of the housing 14 extends through the first side 30 and the second side 34. The transverse axis 50 is perpendicular to the longitudinal axis 46.

[0020] 3-5, the housing 14 further includes an interior cavity 58 defined therein. Each battery cell assembly 18 is disposed within the interior cavity 58. Additionally, the housing 14 is sealed such that the interior cavity 58 is not in fluid communication with the exterior of the battery pack assembly 10. In other embodiments (not shown), the housing 14 may not be sealed.

[0021] 4-7, each battery cell assembly 18 includes a plurality of battery cells 62, a plurality of bus bars 66, and a housing or frame 70 that supports the plurality of battery cells 62 within the interior cavity 58. Each battery cell 62 has a body 74 that extends between a first end 78 and a second end 82. Additionally, each body 74 extends along a battery cell axis 86 (FIG. 5) that extends through each of the respective first and second sides 30, 34 of the housing 14.

[0022] A support plate 90 (FIG. 6) is secured to each of the battery cell assemblies 18 at its upper surface adjacent the upper surface 22 of the housing 14. In addition, longitudinal ends of the battery cell assemblies 18 are secured to fan cowls 91a and 91b (FIG. 5A) provided adjacent the first end 38 or second end 42, respectively, of the housing 14. The fan cowls 91a, 91b may be coupled to the battery cell assemblies 18 before the support plate 90 is secured to the cell assemblies 18 to assist in aligning the support plate 90 with the cell assemblies 18. The fan cowls 91a, 91b receive one or more fans 92 operable to generate airflow within the interior cavity 58 to provide a thermal benefit to the battery pack assembly 10. The battery pack assembly 10 also includes a main printed circuit board (PCB) 94 coupled to the support plate 90. The main PCB 94 supports control circuitry 98 for controlling the operation of the battery pack assembly 10.

[0023] Each battery cell assembly 18 is disposed within the interior cavity 58 such that each of the battery cells 62 is oriented relative to the longitudinal axis 46 of the housing 14. In the illustrated embodiment, the battery cell axis 86 of each corresponding battery cell 62 extends orthogonal to the longitudinal axis 46 (i.e., parallel to the transverse axis 50) within the interior cavity 58. In other embodiments, the battery cell axes 86 may be oriented parallel to the longitudinal axis 46 and / or some of the battery cell axes 86 may be oriented in the same or different directions. In the illustrated embodiment, each battery cell assembly 18 includes 70 battery cells 62. In other embodiments, the battery cell assembly 18 may include two or more battery cells 62. The housing 14 is shaped and sized to receive a predetermined number of battery cell assemblies 18, with each battery cell assembly 18 having a portion of the predetermined number of battery cells 62.

[0024] 6-9, the frame 70 of each battery cell assembly 18 includes a first support member 102 and a second support member 104 coupled to the first support member (e.g., via fasteners 112). Each support member 102, 104 defines a number of cylindrical recesses 108 corresponding to the battery cells 62. The recesses 108 of the first support member 102 receive the first ends 78 of the battery cells 62, and the recesses 108 of the second support member 104 receive the second ends of the battery cells 62. As a result, each support member 102, 104 has the same number of recesses 108 as the number of battery cells 62. The illustrated recesses 108 are arranged in columns (i.e., along a direction perpendicular to both the vertical and horizontal axes 46, 50). And, adjacent recesses 108 in a column are offset with respect to each other. Accordingly, the support members 102 , 104 position and maintain the position of each battery cell 62 within the interior cavity 58 .

[0025] Within the battery pack assembly 10, the first support member 102 of each battery cell assembly 18 is positioned adjacent to the respective side surface 30 or 34. The second support member 104 is disposed opposite the first support member 102 and inwardly relative to the first support member 102 within the internal cavity 58. Each support member 102, 104 of the two battery cell assemblies 18 includes a side surface 116 (FIGS. 6 and 7). The side surfaces 116 of the second support members 104 are disposed in opposing relationship to one another within the internal cavity 58. The side surfaces 116 of the first support members 102 face away from one another and support at least a portion of the bus bars 66 of each battery cell assembly 18.

[0026] 10, each battery cell 62 includes a positive terminal 120 and a negative terminal 124, each disposed at the first end 78. The positive terminal 120 is disposed at a central region of the first end 78. The negative terminal 124 is disposed radially outward from the positive terminal 120. In the illustrated embodiment, the negative terminal 124 is formed as part of the canister crimp of the battery cell 62. An insulator or gasket 128 separates the positive terminal 120 from the negative terminal 124 to prevent shorting. Each battery cell 62 may have a nominal voltage of about 3V to about 5V and a nominal capacity of about 2Ah to about 6Ah (in some cases, about 3Ah to about 5Ah). The battery cells 62 may be of any type of rechargeable battery cell chemistry type, such as lithium (Li), lithium ion (Li-ion), other lithium-based chemistries, nickel-cadmium (NiCd), nickel metal hydride (NiMH), etc.

[0027] 6 and 7, the battery cells 62 may be connected in series, parallel, or a combination of series and parallel to provide the desired electrical characteristics (e.g., nominal voltage, current output, current capacity, power capacity, etc.) of the battery pack assembly 10. The battery cells 62 may be electrically connected by bus bars 66. In the illustrated embodiment, the battery cells 62 are connected in a series-parallel arrangement, with five groups of battery cells 62 connected in parallel and each group having 14 battery cells 62 connected in series (i.e., a "14s5p" arrangement). The two battery cell assemblies 18 are connected in series with each other along the main positive and negative terminals 126, 127 of the battery pack assembly 10. Accordingly, the battery pack assembly 10 includes a total of 140 battery cells 62 arranged in five parallel-connected groups of 28 series-connected battery cells 62 (i.e., a "28s5p" battery pack assembly).

[0028] 11 , the first support member 102 includes a plurality of openings 132 extending between the side surface 116 and a bottom surface of each cylindrical recess 108. The openings 132 expose the positive and negative terminals 120, 124 of each battery cell 62. The bus bars 66 extend vertically along the side surface 116 and are disposed between each row of battery cells 62. Each battery cell assembly 18 also includes a voltage sensing PCB 136 adjacent the main PCB 94 and supported on the side surface 116 of the first support member 102 adjacent the top surface 22 of the housing 14. The voltage sensing PCB 136 may be electrically coupled to the bus bars 66 (e.g., via bonded wires 140 or soldering as discussed below) and configured to sense the voltage of the battery cells 62.

[0029] In the illustrated embodiment, each battery cell 62 is connected by wires 140 (e.g., by a wire bonding process such as welding) to two adjacent bus bars 66 that extend on either side of the battery cell 62. In the illustrated embodiment, from the frame of reference of FIG. 11 , the positive terminal 120 of each battery cell 62 is connected by one wire 140 to the adjacent bus bar 66 located to the left of the battery cell 62. Each negative terminal 124 of each battery cell 62 is connected by one wire 140 to the adjacent bus bar 66 located to the right of the battery cell 62. Thus, the positive terminals 120 of the five battery cells 62 in each column are each connected by wires 140 to the adjacent bus bar 66 located to the left, and the negative terminals 124 of the five battery cells 62 in each column are each connected by wires 140 to the adjacent bus bar 66 located to the right. Each bus bar 66 is coupled to at least two or more battery cells 62. In the illustrated embodiment, each bus bar 66 is coupled to ten battery cells 62 (i.e., five negative terminals 124 to the left of the bus bar 66 and five positive terminals 120 to the right of the bus bar 66).

[0030] 11-14, each illustrated busbar 66 is formed as an elongated conductor 144 having a longitudinal ridge or base 148, a plurality of first fingers 152a projecting laterally outwardly from a first side of the base 148, and a plurality of second fingers 152b projecting laterally outwardly from an opposite second side of the base 148. The fingers 152a, 152b are generally equal in width and each project the same lateral distance outwardly from the base 148. The fingers 152a, 152b are generally planar and each extend in a first plane P1 (FIG. 14). The base 148 is also generally planar and extends in a second plane P2 that is parallel to and offset from the first plane P1. A first connector 156 connects the base 148 to the first finger 152a, and a second connector 160 connects the base 148 to the second finger 152b. The fingers 152a, 152b are offset from one another and arranged in a staggered or alternating configuration along the longitudinal length of the busbar 66. In other words, moving along the longitudinal length of the busbar 66 from the first longitudinal end toward the opposite second longitudinal end, each first finger 152a is followed by a second finger 152b, which is then followed by the subsequent first finger 152a, which is then followed by the subsequent second finger 152b, and so on.

[0031] 11 , the first finger 152a is connected by wire 140 to the negative terminal 124 of each adjacent battery cell 62, and the second finger 152b is connected by wire 140 to the positive terminal 120 of each adjacent battery cell 62. For two adjacent bus bars 66, the first finger 152a of one bus bar 66 is aligned with the second finger 152b of the adjacent bus bar 66 along the direction of the longitudinal axis 46 ( FIG. 2 ). As a result, the first finger 152a of one bus bar 66 extends away from the second finger 152b of the adjacent bus bar 66, and the second finger 152b of one bus bar 66 extends toward the first finger 152a of the adjacent bus bar 66.

[0032] 6 and 7, each battery cell assembly 18 includes primary bus bars 66a, 66b disposed at each longitudinal end (i.e., one at each end) of the first support member 102. The primary bus bar 66a extends along a side 116 of the first support member 102 near its front edge adjacent the first end 38 of the housing 14 and connects to a main positive or negative terminal 126 or 127 of the battery pack assembly 10. The primary bus bar 66b extends along a side 116 of the first support member 102 near its rear edge adjacent the second end 42 of the housing 14 and connects to an intermediate positive or negative terminal 164 or 168 of the battery cell assembly 18. For a battery cell assembly 18 having a main positive terminal 126, the primary bus bar 66a connects (via wire 140) to the positive terminal 120 of the adjacent battery cell 62, and the primary bus bar 66b connects to the negative terminal 124 of the adjacent battery cell 62. Conversely, for a battery cell assembly 18 having a main negative terminal 127, the primary bus bar 66a connects to the negative terminal 124 of the adjacent battery cell 62, and the primary bus bar 66b connects to the positive terminal 120 of the adjacent battery cell 62.

[0033] In addition to connecting the fingers 152a, 152b to the battery cells 62 as described above, the wires 140 can also be bonded to other components to form additional electrical connections within the battery pack assembly 10. For example, the wires 140 can also connect each bus bar 66 to the voltage sense PCB 136. In the same or other embodiments, the wires 140 can form one or more electrical connections between the voltage sense PCB 136 and the main PCB 94. In addition, the wires 140 can connect the primary bus bars 66b of the two battery cell assemblies 18 to each other to electrically connect the two battery cell assemblies 18 to each other. In some embodiments, the wires 140 can form a reverse connection between the two primary bus bars 66b. Utilizing the wires 140 to form other electrical connections within the battery pack assembly 10 in addition to the connections between the bus bars 66 and the battery cells 62 improves manufacturing efficiency.

[0034] 15 and 16 illustrate an embodiment of the battery cell assembly 18 in which the bus bars 66 are alternately positioned toward or away from the side surface 116 of the first support member 102 as they move along the direction of the longitudinal axis 46. More specifically, for two adjacent bus bars 66, one of the adjacent bus bars 66 is oriented toward the base 148 closer to the side surface 116 than the fingers 152a, 152b, and the other of the adjacent bus bars 66 is oriented toward the fingers 152a, 152b closer to the side surface 116 than the base 148. In addition, as illustrated diagrammatically in FIG. 16, each pair of two adjacent bus bars 66 of the battery cell assembly 18 is positioned with the fingers 152a, 152b of both bus bars 66 aligned along the plane P3. In other words, all the fingers 152a, 152b of the bus bars 66 are positioned in-plane with each other, and the bases 148 are positioned out-of-plane with each other. In other embodiments (not shown), the fingers 152a, 152b can still be disposed in-plane with respect to one another, but the bus bars 66 can each face in the same direction, for example, so that each of the bases 148 is adjacent to a side 116, or each of the fingers 152a, 152b is adjacent to a side 116.

[0035] 17 and 18 illustrate another embodiment of a battery cell assembly 18 similar to the embodiment of FIGS. 15 and 16, except that the fingers 152a, 152b of adjacent bus bars 66 are disposed out-of-plane with respect to one another. Specifically, like the embodiment of FIGS. 15 and 16, the bus bars 66 in the embodiment of FIGS. 17 and 18 are alternately disposed toward or away from the side 116 of the first support member 120. However, unlike the embodiment of FIGS. 15 and 16, the bus bars 66 in the embodiment of FIGS. 17 and 18 are disposed such that adjacent bus bars 66 have their fingers 152a, 152b disposed out-of-plane with respect to one another. Similarly, the bases 148 of adjacent bus bars 66 are also disposed out-of-plane with respect to one another. The fingers 152a, 152b of one bus bar 66 are centered on the fourth plane P4, the fingers 152a, 152b of an adjacent bus bar 66 are centered on the fifth plane P5, the base 148 of one bus bar 66 is centered on the sixth plane P6, and the base 148 of an adjacent bus bar 66 is centered on the seventh plane, each of the planes P4, P5, P6, and P7 being parallel to each other and offset from each other.

[0036] 19 illustrates another embodiment of a battery cell assembly 18 in which the bus bars 66 are formed in a non-linear manner. Specifically, the bus bars 66 are formed having a zigzag shape and do not include any fingers. The zigzag bus bars 66 are disposed between adjacent rows of battery cells 62, and adjacent zigzag bus bars 66 are alternately disposed such that bends 172 of the bus bars 66 alternately protrude toward and away from one another.

[0037] 20 illustrates another embodiment of a battery cell assembly 18 in which the bus bars 66 are formed with a non-linear shape. Specifically, the bus bars 66 include rounded notches 176 formed along each side that correspond to the outer diameter of the battery cells 62. The bus bars 66 are disposed between adjacent rows of battery cells 62, with adjacent bus bars 66 being staggered such that the rounded notches 176 of the bus bars 66 alternate toward and away from one another.

[0038] 21 illustrates another embodiment of a battery cell assembly 18 in which the bus bars 66 include fingers 152a, 152b having unequal widths. Specifically, the fingers 152a, 152b located toward the longitudinal ends of the bus bars 66 are of relatively smaller width and the fingers 152a, 152b located toward the longitudinal center of the bus bars 66 are of relatively larger width. The fingers 152a, 152b of a single bus bar 66 are offset from one another along the direction of the longitudinal axis 46 (FIG. 2).

[0039] 22 illustrates another embodiment of the battery cell assembly 18 in which the bus bars 66 are formed having an “L” shape. The bus bars 66 include a long vertically extending leg 180 that is positioned between the rows of battery cells 62 and a short horizontally extending leg 184 that protrudes from one end of the bus bar 66. The bus bars 66 are arranged in an alternating manner, with the short leg 184 of one bus bar 66 positioned adjacent to the voltage sensing PCB 136 and the short leg 184 of the next adjacent bus bar 66 spaced away from the voltage sensing PCB 136.

[0040] 23 illustrates, in a schematic manner, another embodiment of the battery cell assembly 18 in which the fingers 152a, 152b of each bus bar 66 are staggered relative to one another and spaced apart by alternating short and long intervals along the longitudinal direction of the bus bar 66. Moreover, adjacent bus bars 66 are "flip-flopped" horizontally relative to one another such that each of the second fingers 152b are horizontally aligned with one another along the direction of the longitudinal axis 46 (FIG. 2) and each of the first fingers 152a are horizontally offset. This arrangement allows the fingers 152a, 152b to extend relatively closely toward the positive and negative terminals 120, 124 of the battery cells 62, minimizing the length of the wires 140 for connecting the fingers 152a, 152b to the terminals 120, 124.

[0041] 24 illustrates generally another embodiment of a battery cell assembly 18 in which the fingers 152a, 152b of each bus bar 66 are staggered relative to one another and spaced apart by alternating short and long intervals along the longitudinal direction of the bus bars 66. Moreover, adjacent bus bars 66 are "flip-flopped" horizontally relative to one another. Moreover, because the bus bars 66 are of different lengths and vertically offset, no fingers 152a, 152b are horizontally aligned with one another between adjacent bus bars 66 along the direction of the longitudinal axis 46 (FIG. 2).

[0042] 25 illustrates another embodiment of the battery cell assembly 18 in which the bus bars 66 are formed as elongated flat lines. Specifically, the bus bars 66 are rectangular and do not vary in width along their longitudinal length.

[0043] 26 and 27 diagrammatically illustrate an embodiment of a battery cell assembly 18 in which only primary bus bars 66a, 66b are provided (only primary bus bar 66a is shown). As a result, the embodiment of FIG. 26 and FIG. 27 does not include bus bars 66 between the rows of battery cells 62. Instead, the battery cells 62 are electrically connected to each other in a series / parallel arrangement by wires 140 themselves, which are attached by wire bonding. Specifically, the wires 140 extend to connect the positive and negative terminals 120, 124 of the battery cells 62 to establish the series / parallel arrangement. The wires 140 also connect the positive terminals of the battery cells 62 in the last row to the primary bus bar 66a. In other embodiments (not shown), the primary bus bars 66a, 66b may be omitted.

[0044] FIG. 28 illustrates another embodiment of the battery cell assembly 18 in which the bus bar 66 includes fingers 152a, 152b that are directly connected to the positive and negative terminals 120, 124 of the battery cells 62 by precision welding.

[0045] In some embodiments, such as the embodiments of Figures 5A-8, 11, and 19-25, the bus bars 66, 66a, 66b are coupled to the side 116 by fasteners 134. In some embodiments, such as the embodiments of Figures 29-47, the bus bars 66, 66a, 66b are molded into the first and second support members 102, 104 and are thus coupled to the first and second support members 102, 104 without fasteners. It should be understood that the following discussion of the first support member 102 of Figures 29-47 and the bus bars 66, 66a, 66b coupled thereto of the battery assembly 18 has the same or similar features as the first support member 102 and bus bars 66, 66a, 66b of the battery assembly 18 embodiments described above, unless otherwise noted.

[0046] As shown in FIG. 31 for the first support member 102, the side 116 has a plurality of elongated recesses 200 extending vertically along the side 116 and disposed between each row of recesses 108. The elongated recesses 200 are configured to receive the bus bars 66, 66a, 66b. As shown in FIG. 32, the elongated recesses 200 each have a first portion 204 with a lowermost surface defining a first plane P8 and a second portion 216 with a lowermost surface defining a second plane P9. The second plane P9 is offset from the first plane P8 parallel to the first plane P8. The intermediate bus bar 66 includes a second portion 216a disposed adjacent one of the adjacent rows of recesses 108 and a second portion 216b disposed adjacent the other of the adjacent rows of recesses 108. In the illustrated embodiment, the second portions 216a, 216b are aligned and therefore have their lowermost surfaces in the same plane P9. In other embodiments, the second portions 216a, 216b may be staggered or have other suitable configurations. The second portions 216 of the external elongated recesses 200a, 200b (e.g., the front and rear elongated recesses 200 extending adjacent the front and rear edges) extend from one side of the first portion 204. As a result, the front elongated recess 200a has the second portion 216 disposed adjacent to the front row of recesses 108, and the rear elongated recess 200b has the second portion 216 disposed adjacent to the rear row of recesses 108. Additionally, the front elongated recess 200a includes an upper recess 200a' and the rear elongated recess 200b includes an upper recess 200b'. Upper recesses 200a', 200b' are disposed in the upper surface of the first support member 102 adjacent the front and rear edges.

[0047] In some embodiments, a plurality of openings 230 (FIG. 31) extend through the side 116 and are configured to align with corresponding openings 234 (FIG. 29) in the voltage sense PCB 136. The aligned openings 230, 234 are configured to receive portions of the bus bars 66, 66a, 66b, as discussed in more detail below.

[0048] In the illustrated embodiment, there are thirteen intermediate bus bars 66, a first primary bus bar 66a, and a second primary bus bar 66b. In other embodiments, there may be more or fewer intermediate bus bars 66. Each of the bus bars 66, 66a, 66b has a shape that complements the shape of the corresponding recess 200, 200a, 200b in which the bus bar 66, 66a, 66b is disposed.

[0049] In the illustrated embodiment, the intermediate busbar 66 includes a first portion 238 formed from an elongated conductor 244 each having a longitudinal ridge or base 248, a plurality of first fingers 252a projecting laterally outward from a first side of the base 248, and a plurality of second fingers 252b projecting laterally outward from an opposite second side of the base 248. The fingers 252a, 252b are generally equal in width and each project the same lateral distance outward from the base 248. The fingers 252a, 252b are generally planar and each extend in a first plane P10 (FIGS. 38 and 39). The base 248 is also generally planar and extends in a second plane P11 that is parallel to and offset from the first plane P10. The base 248 defines a recess 254 extending along its length. A first connector 256 connects the base 248 to the first finger 252a, and a second connector 260 connects the base 248 to the second finger 252b. In the embodiment of Figures 29-39, the fingers 252a, 252b are aligned with one another along the longitudinal length of the busbar 66. The intermediate busbar 66 also includes a second portion 262 that is coupled (e.g., via fasteners such as rivets or by any other suitable means). The second portion 262 is formed from a generally L-shaped conductive member. A first leg 262a of the L-shape is coupled to a bottom surface of the elongated conductor 244 at a first end and extends beyond the first end of the elongated conductor 244. A second leg 262b of the L-shape extends perpendicularly from the first leg 262a.

[0050] Each of the primary busbars 66a, 66b includes a first portion 238 with a generally L-shaped conductor 244. A first leg 244a of the L-shaped conductor 244 has a longitudinal ridge or base 248 with a plurality of fingers 252 projecting laterally outward from one side of the base 248. That is, the rear busbar 66b includes fingers 252 that extend laterally outward (e.g., in a first direction toward the battery cells 62) from a first side of the base 248, and the front busbar 66a has fingers 252 that project laterally outward (e.g., in a second direction toward the battery cells 62) from a second side of the base 248. The fingers 252 are generally equal in width and each project outward from the base 248 the same lateral distance. The fingers 252 are generally flat and each extend into the first plane P10 (FIGS. 42, 43, 46, 47). The base 248 is also generally planar and extends in a second plane P11 that is parallel to and offset from the first plane P10. A connection 256 connects the base 248 to the fingers 252. The second leg 244b of the L-shaped conductor 244 is configured to receive and secure the respective anode terminals 126, 164 and negative terminals 127, 168 as discussed above. In the illustrated embodiment, the respective anode terminals 126, 164 and negative terminals 127, 168 may be coupled to apertures extending through the second legs via a press-fit engagement or another suitable type of engagement (e.g., threaded engagement, etc.).

[0051] Like the intermediate bus bar 66, the primary bus bars 66a, 66b also include a second portion 262 that is coupled (e.g., via fasteners such as rivets or by any other suitable means) to the first portion 238 (e.g., to a bottom surface of the first leg 244a). The second portion 262 is formed from a conductive member having a first leg 262a, a middle leg 262c extending from the first leg 262a, and a second leg 262b extending from the middle leg 262c. The first leg 262a is coupled at a first end to a bottom surface of the first leg 244a of the first portion 238. The middle leg 262c extends laterally outward from the first leg 262a. The second leg 262b extends perpendicularly from the middle leg 262c.

[0052] In the illustrated embodiment, the first portion 238 of each of the bus bars 66, 66a, 66b is formed from a first conductive material, such as a material including aluminum or an aluminum alloy (e.g., AL3003), and the second portion 262 of each of the bus bars 66, 66a, 66b is formed from a second, different conductive material, such as a material including copper or a copper alloy. In the illustrated embodiment, the second portion 262 is nickel and tin plated. That is, the second portion 262 has an outer layer formed from nickel and tin. In the illustrated embodiment, each of the anode terminals 126, 164 and the negative terminals 127, 168 may be formed from a third conductive material, such as a material including steel.

[0053] The bus bars 66, 66a, 66b are configured to be disposed within corresponding elongated recesses 200 of the first support member 102. Specifically, the base 248 is disposed within and supported by the first portion 204 of the corresponding elongated recess 200, while each of the fingers 252, 252a, 252b is disposed within and supported by the corresponding second portion 216, 216a, 216b of the elongated recess 200, 200a, 200b. Specifically, with respect to the intermediate bus bar 66, each of the first fingers 252a is disposed within the second portion 216a, and each of the second fingers 252b is disposed within the second portion 216b of the elongated recess 200. With respect to the outer bus bars 66a, 66b, the second legs 244b are disposed within the upper recesses 200a′, 200b′. Additionally, the recess 254 defined by the base 248 of each bus bar 66, 66a, 66b faces outwardly relative to the side surface 116. Also, when the bus bars 66, 66a, 66b are disposed within the respective elongated recesses 200, 200a, 200b of the first support member 102, the respective second legs 262b of the second portion 262 are configured to be received within the pair of aligned openings 230, 234 in the side surface 116 and the voltage sensing PCB 136. Accordingly, the respective distal ends of the respective second legs 262b extend from the side surface 116. As shown, the respective distal ends of the respective second legs 262b are in the same plane P12. The second legs 262b of the bus bars 66, 66a, 66b are each soldered to the voltage sense PCB 136 to electrically connect the bus bars 66, 66a, 66b to the voltage sense PCB 136. Finally, a connection member 270 is disposed within a recess in each base 248 and is integrally formed with the side 116 of the first support member 102 at the opposing ends of the first portions 238 of the bus bars 66, 66a, 66b. Specifically, the connection members 270 are formed by filling (e.g., via injection molding) the recess 254 in the corresponding base 248 of each bus bar 66 with the plastic material that forms the remainder of the first support member 102 such that each of the connection members 270 is integrally joined with the side 116 of the first support member 102 at the opposing ends of the first portions 238 of the bus bars 66, 66a, 66b.As shown, the connection member 270 is elongated and linear, thus leaving the fingers 252, 252a, 252b exposed for connection with the battery cells 626 via bonded wires 140, as discussed above. Accordingly, the bus bar 66 is coupled to the first support member 102 via injection molding rather than fasteners.

[0054] The following method may be used to form the battery assembly 18 of Figures 29-47. The first support member 102 and the second support member 104 may each be formed from a plastic material. The bus bars 66, 66a, 66b may be disposed in one of the elongated recesses 200, 200a, 200b of the first support member 102 and the second support member 104. The connecting member 270 may be formed by injecting the respective recesses 254 of the base 248 with a plastic material such that the plastic material fills the recesses 254 and is integrally formed with each of the first support member 102 and the second support member 104. This process leaves the fingers 252, 252a, 252b exposed. The battery cells 62 are disposed between the first support member and the second support member. A wire is bonded between each finger 252, 252a, 252b of the bus bar 66, 66a, 66b and either the positive terminal 126, 164 or the negative terminal 127, 168. The method further includes coupling (e.g., soldering) the second leg 262b of the second portion 262 of the bus bar 66, 66a, 66b to the voltage sensing PCB 136.

[0055] The shapes of the elongated recesses 200, 200a, 200b and the corresponding bus bars 66, 66a, 66b in FIGS. 29-47 are merely examples. In other embodiments, the elongated recesses 200, 200a, 200b and the bus bars 66, 66a, 66b may have other suitable complementary shapes. For example, in some embodiments, the second portion 262 may be omitted from the bus bar 66, 66a, 66b configurations in FIGS. 29-47. In such cases, the bus bars 66, 66a, 66b may alternatively be electrically coupled to the voltage sense PCB 136 in other manners (e.g., via wire bonding, welding, or other suitable methods). In another example, the elongated recesses 200, 200a, 200b may be shaped to accommodate any other bus bar 66, 66a, 66b configurations disclosed herein.

[0056] Although the present disclosure has been described in detail with reference to certain preferred embodiments, variations and modifications exist within the scope and spirit of one or more independent aspects of the disclosure described.

Claims

1. 1. A method of forming a mobile power source, comprising: forming a frame having a first support member and a second support member each formed from a plastic material, the frame including a plurality of cylindrical recesses arranged in a vertical row for receiving a plurality of battery cells and an elongated recess for supporting the plurality of battery cells, each of the elongated recesses being disposed adjacent to at least one row of the plurality of cylindrical recesses; disposing bus bars in one of the elongated recesses of the first support member, each bus bar including an elongated conductor having a base and fingers extending laterally away from the base, the base defining a recess, the fingers extending in a first plane, and the base extending in a second plane parallel to and offset from the first plane; injecting a plastic material into each of the recesses in the base such that the plastic material fills the recesses and forms integrally with the first support member; disposing a plurality of battery cells between the first support member and the second support member such that the plurality of cylindrical recesses of the first support member and the second support member support a plurality of battery cells, each of the battery cells having a first end, a second end opposite the first end, a positive terminal disposed at the first end, and a negative terminal disposed at the first end; and wire bonding a wire between each of the fingers of the bus bar and either the anode terminal or the cathode terminal. method.

2. 2. The method of claim 1, wherein injecting the recesses in each of the bases with the plastic material such that the plastic material is integral with the first support member includes leaving the fingers exposed.

3. 2. The method of claim 1 , wherein each of the bus bars includes a first portion having the base and the fingers and a second portion coupled to the first portion and extending from the first portion, the first portion being formed from a first conductive material and the second portion being formed from a second conductive material different from the first conductive material.

4. The method of claim 3 , further comprising coupling the second portion to a voltage sensing PCB.

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