Battery pack

Abstract

A battery pack (501) according to the present invention comprises: a plurality of batteries (511) which are stacked upon each other; a first holding member (521) which holds the plurality of batteries from one end side of the stacking direction; a second holding member (522) which holds the plurality of batteries from the other end side of the stacking direction; and linking members (525, 526) which connect the first holding member and the second holding member to each other in the stacking direction. The first holding member extends over a first length (L51) in the stacking direction from the one end to a first position (P51) at which the first holding member is directly or indirectly in contact with a battery. The first length is not less than a second length (L52) in the stacking direction of the batteries.

Description

Technical Field

[0001] The present invention relates to a battery pack in which a plurality of batteries are stacked.

Background Art

[0002] As this type of battery pack, there is disclosed one having a plurality of stacked battery cells (an example of a plurality of batteries), a bus bar case fixed to the plurality of battery cells, and a plurality of covers that cover and protect the bus bar case (Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the battery pack described in Patent Document 1, when the number of battery cells is changed according to requirements, the overall length changes, so the length in the stacking direction of the battery cells such as the bus bar case and the gas hose, and the position of the electrode terminal which is the power extraction part change.

[0005] The present invention has been made to solve such problems, and an object thereof is to provide a battery pack that can minimize changes in components even when the number of constituent batteries (for example, battery cells) changes.

Means for Solving the Problems

[0006] In view of the above problems, the assembled battery of the present invention according to the present application includes a plurality of stacked batteries, a first holding member that holds the plurality of batteries from one end side in the stacking direction, a second holding member that holds the plurality of batteries from the other end side in the stacking direction, and a connecting member that connects the first holding member and the second holding member along the stacking direction. The first holding member extends along the stacking direction over a first length to a first position that is in direct or indirect contact with the battery from the one end side. The first length is equal to or greater than a second length of the battery along the stacking direction.

Advantages of the Invention

[0007] According to the present invention, even if the number of batteries changes, changes in components can be minimized. Further features related to the present invention will become apparent from the description of this specification and the accompanying drawings. Also, problems, configurations, and effects other than those described above will be clarified by the description of the following embodiments.

Brief Description of the Drawings

[0008]

Figure 1

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Embodiments for Carrying Out the Invention

[0009] Next, embodiments of the present invention will be described.

[0010] FIG. 15 is a plan view conceptually showing an embodiment of the assembled battery of the present invention.

[0011] The assembled battery 100 includes a plurality of battery cells (single cells) 101, a first end member 102 that holds these plurality of battery cells 101 from one end side in the stacking direction, a second end member 103 that holds them from the other end side in the stacking direction, and a connecting member 104 that connects the first end member 102 and the second end member 103. The first end member 102 protrudes from the connection position P1 in the stacking direction with the connecting member 104 toward the battery cell 101 by a predetermined length L4, and this predetermined length L4 is equal to or greater than the thickness L2 of the battery cell 101 in the stacking direction. Note that the reference sign P2 in FIG. 15 represents the connection position of the second end member 103 in the stacking direction with the connecting member 104.

[0012] According to the configuration of the assembled battery 100 shown in FIG. 15, by using an end member with a thickness different from that of the first end member 102 instead of the first end member 102, it is possible to obtain assembled batteries with the same outer shape but different numbers of battery cells 101. For example, by using an end member that is thinner than the predetermined length L4 by which the first end member 102 protrudes by the thickness of one battery cell, it is possible to form an assembled battery with a specification in which the number of battery cells 101 is increased by one. Also, for example, by using an end member that is thicker than the predetermined length L4 by which the first end member 102 protrudes by the thickness of one battery cell, it is possible to form an assembled battery with a specification in which the number of battery cells 101 is decreased by one.

[0013] These assembled batteries only differ in the number of battery cells, and since the same connecting member 104 and second end member 103 are used, the overall size of the assembled battery does not change, and the outer shapes are the same as each other. Therefore, it is not necessary to newly manufacture each component such as a bus bar case, a gas hose, and a plurality of covers according to the number of cells of the battery cell, and they can be shared. Also, even if the number of cells of the battery cell is changed, the assembly process and fixtures do not change, and it is not necessary to change the settings of the manufacturing equipment, so the equipment can be shared. Also, the problem that the types of components increase and the management man-hours increase does not occur.

[0014] Furthermore, for example, when two electric vehicles of the same vehicle type but with different battery specifications are each equipped with a battery pack having a different number of battery cells, it is possible to mount the battery packs without changing the vehicle body structure for mounting the battery packs, or with only minor changes, and a common vehicle platform can be used. Also, common vehicle parts can be used without changing the routing of the electrical wiring or the routing of the exhaust gas passage for the exhaust gas discharged from the battery cells. In addition, when it becomes necessary to increase the number of battery cells mounted on the vehicle due to a vehicle model change, or when it becomes possible to reduce the number of battery cells mounted on the vehicle due to an improvement in battery performance, it is possible to easily respond without changing the overall size of the battery pack.

[0015] FIG. 16 is a plan view conceptually showing another embodiment of the battery pack of the present invention.

[0016] The battery pack 200 includes a plurality of stacked battery cells (single cells) 201, a spacer 202 stacked together with these plurality of battery cells 201, and a holding member 203 that holds the plurality of battery cells 201 and the spacer 202 along the stacking direction. The holding member 203 holds the plurality of battery cells 201 and the spacer 202 at a total length L1 of a fixed value defined along the stacking direction. And the spacer 202 has a thickness L3 in the stacking direction of the spacer 202 that is equal to or greater than the thickness L2 in the stacking direction of the battery cell 201.

[0017] According to the configuration of the battery pack 200 shown in FIG. 16, by simply using a spacer having a thickness different from that of the spacer 202 instead of the spacer 202, it is possible to obtain battery packs with the same outer shape but different numbers of battery cells 201. For example, by using a spacer that is thinner than the thickness L3 of the spacer 202 by the thickness of one battery cell, it is possible to form a battery pack with a specification in which the number of battery cells 201 is increased by one. Also, for example, by using a spacer that is thicker than the thickness L3 of the spacer 202 by the thickness of one battery cell, it is possible to form a battery pack with a specification in which the number of battery cells 201 is decreased by one.

[0018] These battery packs are the same as the embodiment shown in FIG. 15, except that the number of battery cells is different. The overall size of the battery pack remains the same, and the outer shapes are identical to each other. Therefore, the same effects as those of the embodiment shown in FIG. 15 can be obtained.

[0019] Hereinafter, the battery packs 10 according to the first embodiment of the present invention to the battery packs 10D according to the fifth embodiment will be described with reference to the drawings. (First Embodiment)

[0020] First, the battery cell 1 that constitutes the battery pack 10 according to the first embodiment will be described with reference to the drawings. As shown in FIG. 1, the battery cell 1 includes a battery can 2, a battery lid 3, a positive electrode terminal 4, a negative electrode terminal 5, a gas discharge valve 6, a liquid injection plug 7, an electrolyte (not shown), a charge and discharge element, and an insulating case. A rechargeable secondary battery such as a lithium-ion secondary battery is used for the battery cell 1. The battery cell 1 of the first embodiment corresponds to a single cell of the battery pack according to an embodiment of the present invention.

[0021] The battery can 2 has a rectangular parallelepiped shape with one end of the internal space open, and is made of aluminum or an aluminum alloy. The battery can 2 has a pair of opposing side plates 2a with a large area, a pair of opposing side plates 2b with a small area, and a bottom plate 2c on the side opposite to the opening. In the internal space of the battery can 2, the charge and discharge element is housed in a state covered by the insulating case, and the electrolyte is injected. The positive electrode of the charge and discharge element is connected to the positive electrode terminal 4, and the negative electrode of the charge and discharge element is connected to the negative electrode terminal 5.

[0022] The battery lid 3 has the same rectangular flat plate shape as the bottom plate 2c, is made of aluminum or an aluminum alloy, and closes the opening of the battery can 2. The battery lid 3 is joined to the opening of the battery can 2 by a joining means such as laser welding. The battery lid 3 is formed with a liquid injection hole (not shown) penetrating therethrough. The electrolyte is injected through the liquid injection hole, and the liquid injection hole is closed by the liquid injection plug 7.

[0023] In the central part of the battery cover 3, a gas discharge valve 6 is provided. The gas discharge valve 6 cracks when the battery cell 1 generates heat due to an abnormality such as overcharging and generates gas, and the pressure inside the battery can 2 rises to a predetermined pressure, and discharges the gas from the inside of the container to reduce the pressure inside the battery can 2.

[0024] In addition, through holes (not shown) are formed at one end and the other end of the battery cover 3, and the positive electrode terminal 4 and the negative electrode terminal 5 are attached. The portions of the positive electrode terminal 4 and the negative electrode terminal 5 exposed to the outside from the battery cover 3 are each formed in a rectangular parallelepiped shape and have flat top surfaces. The electric power generated by the battery cell 1 is supplied to an external device via the positive electrode terminal 4 and the negative electrode terminal 5, or the electric power generated externally via the positive electrode terminal 4 and the negative electrode terminal 5 is supplied to a charge-discharge element for charging.

[0025] Next, the assembled battery 10 will be described. The assembled battery 10 is mounted on, for example, a hybrid vehicle driven by an internal combustion engine and a motor or an electric vehicle driven by a motor, and is used as a drive source for the motor. As shown in FIG. 2, the assembled battery 10 has a block 11 and a bus bar case assembly 12.

[0026] (Block 11)

[0027] As shown in FIGS. 3 and 4, Block 11 has a plurality of stacked battery cells 1, spacers 21, a first end spacer 22, a second end spacer 23, a pair of side rails 24, 25, a pair of end plates 26, 27, and a plurality of bolts 28. Block 11 has a laminated structure of stacked battery cells 1 and spacers 21 with each component integrated. Block 11 has a constant length with the pair of side rails 24, 25 and the bus bar case assembly 12. When using a regular-sized end member (not shown) instead of the second end spacer 23, it can hold the maximum number of battery cells 1, and when using the second end spacer 23, it can hold a number of battery cells 1 less than the maximum number. That is, by changing the second end spacer 23 to one with a different thickness, the number of battery cells 1 in Block 11 can be changed without changing the length of Block 11.

[0028] The spacer 21 is made of an insulating synthetic resin. As shown in FIG. 3, it is alternately sandwiched between adjacent battery cells 1 and laminated in the X direction together with the battery cells 1. Each spacer 21 has recesses on both sides corresponding to the shape of the battery cell 1, and holds the battery cell 1 by the recesses, restricting the Y direction and the Z direction. Also, the spacer 21 is provided with claw portions at the upper part in the Z direction and is adapted to fit with claw portions provided on a bus bar case 35 described later.

[0029] The first end spacer 22 is made of an insulating synthetic resin harder than the spacer 21 and is disposed opposite to the battery cell 1 located at one end in the stacking direction. The first end spacer 22 has a recess corresponding to the shape of the battery cell 1 on the opposing surface facing the battery cell 1, holds the battery cell 1 by the recess, and restricts the Y direction and the Z direction. Also, on the side of the first end spacer 22 facing the end plate 27, a fixing bolt hole 22a and a negative electrode connection terminal 22b are provided. Further, a fixing bolt hole 22d for fixing each component is formed at the upper part in the Z direction of the first end spacer 22.

[0030] The second end spacer 23 is made of a synthetic resin that has insulation and is harder than the spacer 21, and is disposed adjacent to the battery cell 1 located at the other end in the stacking direction. As shown in FIG. 3, the second end spacer 23 has a plurality of rectangular cutout holes formed therein, preventing the occurrence of indentations after molding, so-called sink marks, and deformation. The second end spacer 23 has a concave portion corresponding to the battery cell 1 on the opposing surface facing the battery cell 1, and holds the battery cell 1 by the concave portion, regulating the Y direction and the Z direction.

[0031] On the side of the second end spacer 23 facing the end plate 26, a fixing bolt hole 23a, a positive electrode connection terminal 23b, and a gas discharge duct fixing hole 23d are formed. The first end spacer 22 and the second end spacer 23 of the first embodiment correspond to the end members of the assembled battery according to an embodiment of the present invention. The fixing bolt holes 22a and 23a correspond to the fixing portions for fixing the assembled battery to the installation target. The positive electrode connection terminal 23b and the negative electrode connection terminal 22b correspond to connection terminals that are electrically connected to the single battery and electrically connected to the outside of the assembled battery. The gas discharge duct fixing hole 23d corresponds to the fixing portion of the gas discharge duct for discharging the gas that has come out of the single battery to the outside of the assembled battery.

[0032] In the second end spacer 23 of the first embodiment, the distance from the fixing bolt hole 23a to the opposing surface 23f facing the battery cell is equal to or greater than the thickness of the battery cell 1 in the stacking direction. In the present embodiment, the second end spacer 23 is formed to be thicker in the stacking direction by the thickness of n stacked battery cells 1 than the regular-sized end member (regular end member) used when the number of cells is x. Here, x is the maximum number of battery cells 1 that can be stacked in the block 11, and n is an integer smaller than the number x of stacked battery cells 1, and is preferably an even number in order to minimize changes in components. That is, n and x are in the relationship of n < x. Also, the thickness of the n stacked battery cells 1 includes the thickness of the spacer sandwiched between the battery cells 1.

[0033] The length of the second end spacer 23 from each element of the fixing bolt hole 23a, the positive electrode connection terminal 23b, and the gas discharge duct fixing hole 23d to the opposing surface 23f facing the battery cell 1 is larger by an integral multiple of the thickness of the battery cell 1 compared with the regular end member. For example, when the thickness of the second end spacer 23 is larger by twice the thickness of the battery cell 1 than the regular end member, a battery pack with two fewer cells can be made compared with the case of using the regular end member. In the block 11 where the number of cells is 24 when using the regular end member, by using the second end spacer 23 instead of the regular end member, a block 11 with 22 cells can be formed.

[0034] The total length L24 of the regular end member, the 24 battery cells 1 and the spacers, the second end spacer 23 formed thicker by the width of two battery cells 1, and the total length L22 of the 22 battery cells 1 and the spacers are the same length (L24 = L22). And, the positions of the fixing bolt hole 23a, the positive electrode connection terminal 23b, and the gas discharge duct fixing hole 23d of the second end spacer 23 are the same as the positions of the regular end member. As a result, in the block 11, even if the number of cells is decreased by two and changed to 22, components other than the second end spacer 23 do not require design changes such as dimensions and shapes and can be used as they are.

[0035] In addition, in the present embodiment, the case where the second end spacer 23 is thicker than the thickness of one battery cell 1 has been described. However, instead of the second end spacer 23, a regular end member may be used, and a first end spacer 22 formed thicker than the thickness of one battery cell 1 may be used. Further, ones in which both the first end spacer 22 and the second end spacer 23 are made thicker by at least the thickness of one battery cell 1 may be used. In this case, the first end spacer 22 of the first embodiment corresponds to the first end plate or the second end plate of the battery pack according to an embodiment of the present invention, and the second end spacer 23 corresponds to the first end plate or the second end plate.

[0036] The side rail 24 is formed of a metal material, and as shown in FIG. 3, has a rail body 24c extending in the X direction and bent portions 24b that are bent in the Y direction at both ends of the rail body 24c and face each other. Each bent portion 24b is provided with a fixing hole 24a penetrating in the X direction. The bent portions 24b are arranged to face each other from the outside in the stacking direction with respect to the first end spacer 22 and the second end spacer 23, and cover a part of the first end spacer 22 and a part of the second end spacer 23.

[0037] The side rail 24 holds and binds the first end spacer 22, the plurality of battery cells 1, the plurality of spacers 21, and the second end spacer 23 in a state of being pressed in the stacking direction. For the side rail 24, bolts 28 are inserted into the fixing holes 24a of the bent portions 24b and fixed to the end plates 26 and 27.

[0038] When the second end spacer 23 is used, the side rail 24 has a length for stacking 22 battery cells 1. The side rail 25 has a shape similar to that of the side rail 24 as a mirror image. The side rail 25 is formed of the same metal material as the side rail 24 and has the same function as the side rail 24. The side rail 25 is arranged to face the side rail 24 in the Y direction with the stacked battery cells 1 interposed therebetween, and has a rail body 25c extending in the X direction and bent portions 25b that are bent in the Y direction at both ends of the rail body 25c and face each other. The bent portion 25b has a fixing hole 25a through which the bolt 28 is inserted. Note that the pair of side rails 24 and 25 of the first embodiment respectively correspond to the side members of the assembled battery according to one embodiment of the present invention.

[0039] The end plate 26 is formed of a plate-shaped metal material, so-called sheet metal, and is disposed adjacent to the second end spacer 23 as shown in FIG. 3. The end plate 26 has a flat portion 26a in which a positioning through hole for the second end spacer 23 is formed, and a fixing portion 26b for fixing the side rails 24 and 25. The fixing portion 26b has a fixing hole 26c through which a bolt 28 is inserted. The fixing portion 26b has a step recessed in the stacking direction with respect to the flat portion 26a, and is configured such that when the bent portions 24b and 25b of the side rails 24 and 25 are fastened with the bolt 28, the head of the bolt does not protrude from the surface of the flat portion 26a. A nut is attached to the fixing portion 26b. The fixing portion 26b of the first embodiment corresponds to a connection portion with a side member of the assembled battery according to an embodiment of the present invention.

[0040] The end plate 27 is formed in the same manner as the end plate 26 and is disposed adjacent to the first end spacer 22 as shown in FIG. 4. The bent portions 24b and 25b of the end plate 27, the side rail 24, and the side rail 25 are fastened by a bolt 28. Note that the pair of end plates 26 and 27 of the first embodiment respectively correspond to end members of the assembled battery according to an embodiment of the present invention.

[0041] (Bus bar case assembly 12)

[0042] The bus bar case assembly 12 includes a bus bar 31, a harness, a gas discharge duct 234, a plurality of covers 34, and a bus bar case 35 as shown in FIG. 3. The bus bar case assembly 12 has functions such as electrical connection between terminals of the battery cell 1 and between the battery cell 1 and a controller, monitoring of voltage and temperature, and gas discharge.

[0043] As shown in FIG. 5, the bus bar 31 has an inter-cell bus bar 31a, a negative bus bar 31b, and a positive bus bar 31c, and each component is housed in a bus bar case 35. The inter-cell bus bar 31a is configured to electrically connect the positive electrode terminal 4 and the negative electrode terminal 5 of the battery cell 1. The negative bus bar 31b is connected to the second end spacer 23, and the positive bus bar 31c is connected to the first end spacer 22. Note that the negative bus bar 31b has a shape that is longer in the stacking direction of the battery cells 1 compared to the case of the regular end member.

[0044] The harness has a terminal portion, a wire portion, a temperature sensor portion, and a connector portion. The terminal portion is electrically connected to the bus bar 31 and the harness via the wire portion. The temperature sensor portion is in contact with the battery cover 3, measures the temperature of the battery cover 3, and outputs the measurement result. The connector portion is connected to each component and connects each component to a controller (not shown). Each component is stored in the bus bar case 35.

[0045] The gas discharge duct 234 has a gas discharge port 233, and separates and collects the gas discharged from a gas discharge valve (not shown) at the center in the Y direction of the bus bar case 35 and discharges it from the gas discharge port 233. The gas discharge duct 234 is fixed to the female threads of the first end spacer 22 and the second end spacer 23 by screws arranged at both ends in the X direction. The plurality of covers 34 have a function of insulating and protecting the components of the bus bar case assembly 12, and are arranged so as to cover the bus bar 31 and the harness. Each cover 34 is fitted and fixed to the bus bar case 35.

[0046] The bus bar case 35 has a plurality of frames arranged in the stacking direction of the battery cells 1, and is configured to store the inter-cell bus bar 31a, the negative bus bar 31b, and the positive bus bar 31c in the frames respectively. The bus bar case 35 has a plurality of claw portions, and the bus bar case assembly 12 is fixed to the block 11 by fitting the claw portions with the claw portions provided at the upper portions in the Z direction of each spacer 21, the first end spacer 22, and the second end spacer 23 of the block 11.

[0047] The effects of the assembled battery 10 according to the first embodiment will be described.

[0048] The assembled battery 10 according to the first embodiment has a second end spacer 23. The second end spacer 23 is formed to be thicker in the stacking direction by the thickness corresponding to the stacking of n battery cells 1 than the regular end member used when the number of cells is x. The total lengths of the side rails 24 and 25 are the same before and after the change regardless of the change in the number of battery cells 1 included in the block 11. Also, the positions of the fixing bolt holes 23a, the positive electrode connection terminals 23b, and the gas discharge duct fixing holes 23d are the same between the second end spacer 23 and the regular end spacer.

[0049] As a result, it is possible to cope with the change in the number of battery cells 1 only by changing the two components of the second end spacer 23 and the negative electrode bus bar 31b that constitutes the bus bar case assembly 12, and an effect is obtained in that it is not necessary to change the other components of the assembled battery 10. Note that by extending a part of the negative electrode bus bar 31b, it is not necessary to change the bus bar case 35. In the assembled battery 10 according to the present embodiment, it is possible to easily provide a combination of an assembled battery of 24 battery cells 1 in the block 11 and an assembled battery of 22 battery cells 1.

[0050] In a conventional assembled battery, when the number of battery cells is changed, it is necessary to newly manufacture each component of the assembled battery according to the number of cells. In this case, there are problems that the assembly process and jigs change, and the settings of the manufacturing apparatus also need to be changed each time, making it difficult to share the equipment, and that the types of components increase and the management man-hours also increase. On the other hand, in the assembled battery 10 according to the first embodiment, even when the number of battery cells that make up the battery changes, the change in components can be minimized. Also, jigs and equipment can be shared to minimize process changes, and an increase in the management man-hours of components can be suppressed, so an effect is obtained in that the conventional problems can be solved.

[0051] The assembled battery 10 according to the first embodiment has been described for the case where the end plate 26 is made of sheet metal and the thickness of the second end spacer 23 is increased. The assembled battery according to an embodiment of the present invention may be configured with a structure other than the structure of the first embodiment. Hereinafter, the assembled batteries 10A according to the second embodiment, 10B according to the third embodiment, 10C according to the fourth embodiment, and 10D according to the fifth embodiment, which are configured with structures other than the structure of the first embodiment, will be described with reference to the drawings. For the configurations similar to those of the assembled battery 10 according to the first embodiment, the same reference numerals will be used and the detailed description will be omitted. (Second Embodiment)

[0052] FIG. 6 is a perspective view of the assembled battery according to the second embodiment, and FIG. 7 is an exploded perspective view of the assembled battery according to the second embodiment.

[0053] What is characteristic in this embodiment is that the fixed bolt hole 26Ab and the gas discharge duct fixing hole 26Ae are provided in the end plate 26A instead of the end spacer 23A.

[0054] As shown in FIG. 6, the assembled battery 10A according to the second embodiment is composed of a block 11A and a bus bar case assembly 12A. As shown in FIGS. 7 and 8, the block 11A includes a plurality of battery cells 1, a plurality of spacers 21, a first end spacer 22A, a second end spacer 23A, a pair of side rails 24 and 25, a pair of end plates 26A and 27A, and a plurality of bolts 28.

[0055] The first end spacer 22A has a flat opposing surface that faces the end plate 27A on one side in the stacking direction, and a concave portion corresponding to the battery cell 1 is formed on the other side in the stacking direction. The battery cell 1 is held by the concave portion, and it has a configuration that regulates the Y direction and the Z direction. The second end spacer 23A has a flat opposing surface that faces the end plate 26A on the other side in the stacking direction, and a concave portion corresponding to the battery cell 1 is formed on one side in the stacking direction. The battery cell 1 is held by the concave portion, and it has a configuration that regulates the Y direction and the Z direction.

[0056] The second end spacer 23A has a distance between the positive electrode connection terminal 26Ac and the opposing surface 23Af facing the battery cell 1, that is, the thickness of the second end spacer 23A, which is equal to or greater than the thickness of the battery cell 1 in the stacking direction. In the present embodiment, the second end spacer 23A is formed to be thicker in the stacking direction by the number of n stacked battery cells 1 than the regular-sized end member (regular end member) used when the number of cells is x. As the regular end member, one having the same shape as the first end spacer 22A can be used.

[0057] For example, in the block 11 where the maximum number of battery cells 1 is 24, when it is desired to change to a configuration with a decrease of two cells, the second end spacer 23A, which is thicker by the amount of two stacked battery cells 1, is used. Since the second end spacer 23A has a thickness corresponding to the reduction in the number of two battery cells 1 and the spacer 21 interposed therebetween, the position of the end plate 26A remains the same regardless of whether the number of battery cells 1 is 24 or 22. As a result, in the block 11, even when the number of cells is changed from 24 to 22, components other than the second end spacer 23 do not require design changes such as dimensions and shapes and can be used as they are.

[0058] The end plate 26A is formed of a plate-shaped member made of aluminum die-casting, whereas the end plate 26 in the first embodiment is formed of a sheet metal member. The end plate 26A is arranged to face in the X direction, which is the stacking direction, with respect to the second end spacer 23A. The end plate 26A has a fixing portion 26Aa in which fixing bolt holes for fixing the side rails 24 and 25 are formed.

[0059] The end plate 26A is formed with a fixing bolt hole 26Ab and a gas discharge duct fixing hole 26Ae. The fixing bolt hole 26Ab in the second embodiment corresponds to a fixing portion for fixing the assembled battery to an installation target in the assembled battery according to an embodiment of the present invention, and the gas discharge duct fixing hole 26Ae corresponds to a discharge portion for discharging gas out of the assembled battery from inside the single cell.

[0060] The end plate 27A is formed in the same manner as the end plate 26A and is disposed adjacent to the first end spacer 22A as shown in FIG. 8. The end plate 27A is formed with a fixing bolt hole 27Ab for fixing the assembled battery 10A, a negative electrode connection terminal 27Ad, and a gas discharge duct fixing hole 27Ae. The bent portions 24b and 25b of the end plate 27A, the side rail 24, and the side rail 25 are configured to be fastened by bolts 28. Note that the pair of end plates 26A and 27A of the second embodiment respectively correspond to the end members of the assembled battery according to one embodiment of the present invention.

[0061] As shown in FIG. 7, the bus bar case assembly 12A includes a bus bar 31A, a harness, a gas discharge duct 234, a plurality of covers 34A, and a bus bar case 35A. When the number x of battery cells 1 is decreased by 2 and changed to (x - 2), the change is only in the negative bus bar 31Ab of the bus bar 31A, similar to the first embodiment. The harness, the cover 34A, and the bus bar case 35A have the same functions as the harness, the cover 34, and the bus bar case 35 of the first embodiment.

[0062] In the assembled battery 10A according to the second embodiment, the changes associated with the change in the number x of battery cells 1 are only the second end spacer 23A and the negative bus bar 31Ab, and the same effects as those of the assembled battery 10 according to the first embodiment can be obtained. (Third Embodiment)

[0063] FIG. 9 is an exploded perspective view of an assembled battery according to the third embodiment.

[0064] What is characteristic in this embodiment is that the thickness of the second end spacer 23B is thinner than that of the second end spacer 23A of the second embodiment, and the thickness of the end plate 26B is larger than that of the end plate 26A of the second embodiment.

[0065] As shown in Fig. 9, the assembled battery 10B according to the third embodiment is composed of a block 11B and a bus bar case assembly 12A that is the same as that of the second embodiment. The block 11B is formed by die-casting the end plate 26B and the end plate 27A in the same manner as the block 11A of the assembled battery 10A of the second embodiment. However, unlike the block 11A, the shape of the second end spacer 23B is different from the shape of the end plate 26B.

[0066] The second end spacer 23B has a regular size with no extended thickness. A recess corresponding to the shape of the battery cell 1 is formed on one surface in the stacking direction, and the surface facing the end plate 26B on the other side in the stacking direction is formed flat.

[0067] The distance from the fixing bolt hole 26Bb to the opposing surface 26Bf facing the second end spacer 23B of the end plate 26B is equal to or greater than the thickness of the battery cell 1 in the stacking direction. In this embodiment, the end plate 26B is formed to be thicker in the stacking direction by the thickness of n stacked battery cells 1 than a regular-sized end member (regular end member) used when the number of cells is x. The end plate 26B is arranged adjacent to the second end spacer 23B. The end plate 26B has a fixing portion 26Ba formed with fixing bolt holes for fixing the side rails 24 and 25. And the end plate 26B is formed with a fixing bolt hole 26Bb, a positive electrode connection terminal 26Bc, a negative electrode connection terminal 26Bd, and a gas discharge duct fixing hole 26Be.

[0068] For example, in block 11 where up to 24 battery cells 1 can be stacked, when reducing the number of cells to 22 by decreasing the number of cells by 2, an end plate 26B formed thicker by the thickness of two stacked battery cells 1 than the regular end member is used. As a result, the positions of the fixing bolt holes 26Bb, the positive electrode connection terminal 26Bc, the negative electrode connection terminal 26Bd, and the gas discharge duct fixing holes 26Be of the end plate 26B can remain the same and unchanged whether the number of battery cells 1 is 24 or 22. Consequently, in block 11, even when the number of cells is changed from 24 to 22, components other than the end plate 26B do not require design changes such as dimensions and shapes and can be used as they are. (Fourth Embodiment)

[0069] FIG. 10 is an exploded perspective view of the assembled battery according to the fourth embodiment.

[0070] What is characteristic in this embodiment is that the block 11C uses dummy cells 1C for a part of the plurality of battery cells 1.

[0071] The assembled battery 10C according to the fourth embodiment has a block 11C as shown in FIG. 10. The second end spacer 23C and the end plate 26, which are end members of the block 11C, are of regular sizes used when the maximum number of cells is x.

[0072] The dummy cell 1C has the same outer dimensions as the battery cell 1 and is formed of a material such as an aluminum alloy. n dummy cells 1C are stacked adjacent to the battery cell 1. For example, in the reference block 11 where the number of battery cells 1 is stacked at x, when the number of cells x is decreased by 2 and changed to (x - 2), two dummy cells 1C are stacked instead. As shown in FIG. 10, the two dummy cells 1C are arranged to face each other with the spacer 21 in between.

[0073] In the assembled battery 10C according to the fourth embodiment, the changes associated with the change in the number x of battery cells 1 are only the dummy cells 1C and the negative electrode bus bar 31b, and the same effects as those of the assembled battery 10 according to the first embodiment can be obtained. For example, in the block 11 in which 24 battery cells 1 are stacked, when the number of cells is decreased by 2 and changed to 22, by inserting two dummy cells, the positions of the fixing bolt holes 23Ca of the second end spacer 23C, the positive electrode connection terminal 23Cb, and the gas discharge duct fixing holes 23Cd remain unchanged and are the same whether the number of battery cells 1 is 24 or 22. Therefore, it is not necessary to change the design such as the dimensions and shape of each component, and they can be used as they are. (Fifth Embodiment)

[0074] FIG. 11 is a perspective view of the assembled battery according to the fifth embodiment, and FIG. 12 is an exploded perspective view of the assembled battery according to the fifth embodiment.

[0075] What is characteristic in this embodiment is that an extension spacer 21D is provided at an intermediate position in the stacking direction of the plurality of battery cells 1.

[0076] As shown in FIGS. 11 and 12, the assembled battery 10D has a block 11D. The block 11D is formed by stacking a plurality of battery cells 1. And an extension spacer 21D is interposed at an intermediate position in the stacking direction of the plurality of battery cells 1.

[0077] The extension spacer 21D has a thickness corresponding to n battery cells 1. For example, in the block 11 in which a maximum of x battery cells 1 can be stacked, when the number of cells is decreased by 2 to (x - 2), the extension spacer 21D formed to be as thick as two stacked battery cells 1 is used. The extension spacer 21D is located at an intermediate position in the stacking direction in which the battery cells 1 and the spacers 21 are alternately stacked, and is displaced to the side of one end portion rather than the central portion in the stacking direction.

[0078] The plurality of battery cells 1 of block 11D are divided into two in the stacking direction by the extension spacer 21D. Then, a bus bar is attached so as to straddle the extension spacer 21D and connected to each other.

[0079] The extension spacer 21D may be composed of two or more extension spacers. In this case, the total thickness of the widths of the two or more extension spacers is formed to be thicker than the thickness of the battery cell 1. The extension spacer 21D is formed to be thicker than the thickness of the other spacer 21. Also, the arrangement of the extension spacer 21D may be at a position other than the central portion. For example, one or two extension spacers may be arranged adjacent to the battery cell 1 closest to the second end spacer 23C or the first end spacer 22.

[0080] According to the assembled battery 10D according to this embodiment, even if the number of battery cells 1 in block 11D is reduced, by using the extension spacer 21D having the reduced thickness, the positions of the fixing bolt holes 23Ca of the second end spacer 23C, the positive electrode connection terminal 23Cb, and the gas discharge duct fixing holes 23Cd do not change and can be made the same. Therefore, design changes such as dimensions and shapes for each component are not required and it can be used as it is.

[0081] The assembled battery 10 according to the first embodiment to the assembled battery 10D according to the fifth embodiment are used as a power supply device in which a single assembled battery or a plurality of assembled batteries are arranged and electrically connected.

[0082] Next, power supply devices 40 and 50 in which a plurality of assembled batteries 10E are arranged linearly in the stacking direction of the battery cells 1 will be described with reference to FIGS. 13 and 14.

[0083] FIG. 13 is a configuration diagram of a power supply device including two assembled batteries in which a plurality of battery cells are stacked, and FIG. 14 is a configuration diagram of a power supply device including four assembled batteries in which a plurality of battery cells are stacked.

[0084] As shown in FIG. 13, the power supply device 40 includes two sets of battery cells 10E and a bus bar 40a that electrically connects the two sets of battery cells 10E. The set of battery cells 10E is configured in the same manner as the set of battery cells 10 according to the first embodiment. The bus bar 40a connects the positive electrode Pe of the set of battery cells 10E on one side and the negative electrode Ne of the set of battery cells 10E on the other side, which are arranged to face each other. The two sets of battery cells 10E are arranged in series in the closest state by the bus bar 40a.

[0085] Note that the set of battery cells 10E corresponds to the first set of battery cells or the second set of battery cells of the set of battery cells according to an embodiment of the present invention. The stacking direction of the battery cells 1 is corresponding to the first direction, and the bus bar 40a corresponds to the first bus bar. The power supply device 40 may arrange the two sets of battery cells 10E such that the stacking directions of the respective battery cells 1 are in directions orthogonal to each other. In this case, the orthogonal direction corresponds to the second direction of the set of battery cells according to an embodiment of the present invention.

[0086] In the set of battery cells 10E, the first end spacer 22E is formed to be as thick as two battery cells 1. As a result, the set of battery cells 10 and the set of battery cells 10E have the same overall length.

[0087] With this configuration, the power supply device 40 can minimize the length of the bus bar 40a. When the power supply device 40 is mounted on a vehicle, it is arranged to straddle the left - right direction of the vehicle. For example, one set of battery cells 10E is arranged under the left seat, and the other set of battery cells 10E is arranged under the right seat. Therefore, the effect that the weight balance of the vehicle is uniform left - right can be obtained.

[0088] Next, as shown in FIG. 14, the power supply device 50 includes two power supply devices 40, a plate-like structure K fixed to the floor surfaces of two vehicle bodies (not shown), and a plurality of bolts (not shown) for fixing the two power supply devices 40 to the structure K. The two power supply devices 40 are arranged in parallel such that the stacked battery cells 1 face each other. The centers of gravity G1, G2, G3, and G4 as the first centers of gravity of each set of battery cells 10E indicated by circles are located at positions away from the central portion in the stacking direction of the stacked battery cells 1 with respect to the bus bar 40a, and are set at the central portions in the width direction of the set of battery cells 10E orthogonal to the stacking direction.

[0089] The center of gravity G0 as the second center of gravity of the overall structure of the power supply device 50 is located at the center in the vehicle width direction. When mounted on the vehicle, the power supply device 50 is arranged so as to straddle the left-right direction of the vehicle, as indicated by the dashed-dotted line. For example, the left side portion of the power supply device 50 is located below the left seat LS, and the right side portion of the power supply device 50 is located below the right seat RS. Therefore, the center of gravity G0 of the power supply device 50 is located at the central portion between the left and right seats. Note that the front-rear, left-right directions indicate the directions as seen from the vehicle occupant when the occupant is seated on the seat.

[0090] With this configuration, since the power supply devices 40 are arranged in parallel, the power supply device 50 achieves space savings and has the effect of making the overall weight balance uniform.

[0091] Based on the description up to this point with reference to FIGS. 1 to 16, the following expressions are possible.

[0092] <Expression 1> A plurality of single cells to be stacked, A first end member that holds the plurality of single cells from one end side in the stacking direction, A second end member that holds the plurality of single cells from the other end side in the stacking direction, A connecting member that connects the first end member and the second end member, And having The first end member protrudes a predetermined length from the connection position in the stacking direction with the connecting member toward the single cell, The assembled battery is characterized in that the predetermined length is equal to or greater than the thickness in the stacking direction of the single battery.

[0093] <Expression 2> A plurality of single batteries to be stacked, A spacer stacked together with the plurality of battery cells, A holding member that holds the plurality of battery cells and the spacer along the stacking direction, and has The holding member holds the plurality of battery cells and the spacer at a constant total length defined along the stacking direction, The assembled battery is characterized in that the thickness of the spacer in the stacking direction is equal to or greater than the thickness of the single battery in the stacking direction.

[0094] <Expression 3> An assembled battery in which a plurality of single batteries are stacked, A pair of end members arranged to face both sides in the stacking direction of the plurality of single batteries, A pair of side members that are separated from each other in a direction perpendicular to the stacking direction and extend along the stacking direction to connect the pair of end members to each other, The end member has an end plate connected to the side member and an end spacer disposed between the end plate and the single battery, The end plate has any one of a connection portion with the side member, a fixing portion for fixing the assembled battery to an installation target, a connection terminal for electrically connecting to the single battery and electrically connecting to the outside of the assembled battery, and a discharge portion for discharging gas emitted from inside the single battery to the outside of the assembled battery, The assembled battery is characterized in that, in the stacking direction of the single battery, the length from any one of the above configurations to the facing surface facing the single battery is greater than the thickness of the single battery.

[0095] <Expression 4> An assembled battery in which a plurality of single batteries are stacked, A pair of end members arranged to face both sides in the stacking direction of the plurality of single batteries, A pair of side members that are separated from each other in a direction orthogonal to the stacking direction and extend along the stacking direction to connect the pair of end members to each other. The end member includes an end plate connected to the side member, and an end spacer disposed between the end plate and the single battery. The end spacer has any one of a connection portion with the side member, a fixing portion for fixing the assembled battery to an installation target, a connection terminal that is electrically connected to the single battery and electrically connected to the outside of the assembled battery, and a discharge portion for discharging gas emitted from the single battery to the outside of the assembled battery. An assembled battery, characterized in that, in the stacking direction of the single battery, the length from any one of the above configurations to the facing surface facing the single battery is greater than the thickness of the single battery.

[0096] <Expression 5> The pair of side members has a length for stacking and arranging x single batteries when a regular end member is arranged at an end on one side in the stacking direction of the plurality of single batteries. The assembled battery according to Expression 3 or 4, characterized in that at least one of the pair of end members has a thickness in the stacking direction that is thicker than the regular end member by the thickness of n (n < x) single batteries.

[0097] <Expression 6> The assembled battery according to any one of Expressions 3 to 5, characterized in that the length greater than the thickness of the single battery is an integer multiple of the thickness of the single battery.

[0098] <Expression 7> The end member has a plurality of members arranged in the stacking direction of the single battery. The assembled battery according to any one of Expressions 3 to 6, characterized in that the sum of the lengths in the stacking direction of two or more of the plurality of members is greater than the thickness in the stacking direction of the single battery.

[0099] <Expression 8> A plurality of single batteries to be stacked, An end member disposed at both ends in the stacking direction of the single battery, A side member disposed along the stacking direction of the single battery and connected to the end member, and having, The end member is, A first end member disposed at one end in the stacking direction, A second end member disposed at the other end in the stacking direction, and having, In the stacking direction of the single battery, the first end member has a length equal to or greater than the combined length of the length of the second end member and the thickness of the single battery. A battery pack characterized by this.

[0100] <Expression 9> The end member is, An end plate connected to the side member, An end spacer disposed between the single battery closest to the end plate in the stacking direction of the single battery and the end plate, and having, The end plate or the end spacer is, A first end plate or a first end spacer disposed at one end, A second end plate or a second end spacer disposed at the other end, and having, The first end plate has a length equal to or greater than the combined length of the length of the second end plate and the thickness of the single battery in the stacking direction of the single battery, Or, the first end spacer has a length equal to or greater than the combined length of the length of the second end spacer and the thickness of the single battery. The battery pack according to Expression 8, characterized by this.

[0101] <Expression 10> A power supply device applied to a vehicle equipped with a plurality of battery packs according to Expression 8 or 9, The battery pack has a first battery pack and a second battery pack having a plurality of single batteries stacked in a first direction along the stacking direction of the single batteries of the first battery pack, The second battery pack is arranged on a straight line along the first direction or in a second direction orthogonal to the straight line along the first direction. In the first direction, A power supply device, characterized in that an end on the side where the first end member or the first bus bar of the first battery pack is located is closer to the end on the side where the first end member or the first bus bar of the second battery pack is located than the other end.

[0102] <Expression 11> A power supply device applied to a vehicle, comprising the battery pack according to Expression 8 or 9 and a structure provided adjacent to the battery pack, The spacer is lighter than the single battery and is arranged on the side of one end rather than the central part in the stacking direction of a plurality of the single batteries arranged in the stacking direction. The first centroid of the battery pack is located on the side of the other end facing the one end in the stacking direction rather than the central part. The battery pack and the structure are arranged in the vehicle such that a second centroid formed by the battery pack and the structure in the state of being arranged in the vehicle is located closer to the center in the vehicle width direction intersecting the traveling direction of the vehicle than the first centroid of the battery pack in the state of being arranged in the vehicle.

[0103] <Expression 12> A plurality of single batteries to be stacked, A spacer stacked together with the plurality of single batteries, End members located at both ends of the stacked plurality of single batteries and the spacer, And a side member located along the stacking direction of the single battery and connected to the end member. The side member holds the end member, the plurality of single batteries, and the spacer over the entire length of a certain value defined along the stacking direction. The end member has any one of a connection portion with the side member, a fixing portion for fixing the assembled battery to an installation target, a connection terminal that is electrically connected to the single battery and can be electrically connected to the outside of the assembled battery, and a discharge portion that can discharge gas emitted from within the single battery to the outside of the assembled battery. Positioned between any one of the above configurations and the single battery that is farthest from any one of the above configurations, the thickness in the stacking direction of the spacer with the single batteries arranged on both sides is a thickness equal to or greater than the thickness in the stacking direction of any one of the single batteries. The assembled battery is characterized by this.

[0104] <Expression 13> A plurality of single batteries to be stacked, A plurality of spacers stacked together with the plurality of single batteries, End members positioned at both ends of the stacked plurality of single batteries and the spacers, And a side member that is positioned along the stacking direction of the single batteries and is connected to the end member. The side member holds the end member, the plurality of single batteries, and the spacers over the entire length of a fixed value defined along the stacking direction. Among the plurality of spacers, the thickness in the stacking direction of the first spacer is greater than the thickness in the stacking direction of the second spacer. The first spacer is arranged on the side of one end rather than the central portion in the stacking direction of the plurality of single batteries arranged in the stacking direction. The second spacer is arranged on the side of the other end that faces the one end in the stacking direction rather than the central portion, and the difference between the thickness in the stacking direction of the first spacer and the thickness in the stacking direction of the second spacer is equal to or greater than the thickness in the stacking direction of the single battery. The assembled battery is characterized by this.

[0105] <Expression 14> The spacer has two or more spacers between adjacent single batteries in the stacking direction, or has two or more spacers adjacent to the single battery at the stacking end. The length obtained by summing the thicknesses of the two or more spacers in the stacking direction is a thickness greater than or equal to the thickness of the single cell in the stacking direction, the assembled battery according to Expression 12 or Expression 13.

[0106] <Expression 15> The first spacer has a thickness in the stacking direction greater than or equal to the thickness of any of the single cells in the stacking direction. The first spacer is on a plane orthogonal to the stacking direction. The assembled battery according to Expression 12 or Expression 13, wherein the first width in the first direction has a width less than or equal to the first width of the second spacer, or the second width in the second direction orthogonal to the first direction has a width less than or equal to the second width of the second spacer.

[0107] Hereinafter, the assembled battery 501 according to the sixth embodiment of the present invention to the assembled battery 503 according to the eighth embodiment will be described with reference to FIGS. 17 to 21. At that time, the differences from the description with reference to FIGS. 1 to 16 (and the above-described Expressions 1 to 15) will be mainly described, and the description of the common points with the description with reference to FIGS. 1 to 16 (and the above-described Expressions 1 to 15) will be omitted or simplified.

[0108] (Sixth Embodiment) FIG. 17 is a plan view of the assembled battery 501 according to the sixth embodiment. FIG. 18 is a plan view showing a part of the configuration of the assembled battery 501 in FIG. 17.

[0109] The battery pack 501 is fixed to, for example, a module case 700 on the vehicle side (an example of a fixing member outside the battery pack 501). The battery pack 501 includes a plurality of stacked battery cells 511 (an example of a battery), a first end member 521 (an example of a first holding member) that holds the plurality of battery cells 511 from one end side in the stacking direction X, a second end member 522 (an example of a second holding member) that holds the plurality of battery cells 511 from the other end side in the stacking direction X, and a first side rail 525 and a second side rail 526 (an example of a connecting member) that connect the first end member 521 and the second end member 522 along the stacking direction. The first end member 521 may correspond to, for example, the first terminal member 102 (FIG. 15), the spacer 202 (FIG. 16), or the second end spacer 23 (FIG. 3). The second end member 522 may correspond to, for example, the first end spacer 22 (FIG. 3) or the regular end member. The first side rail 525 is, for example, made of metal and may have the same configuration as the side rail 25 (FIG. 4). The second side rail 526 is, for example, made of metal and may have the same configuration as the side rail 24 (FIG. 4). The bolt 528 (an example of a fixing member) is inserted into a through hole formed in the bent portion 525b of the first side rail 525 and fixed to screw grooves formed in the first end member 521 and the second end member 522. Similarly, the bolt 528 (an example of a fixing member) is inserted into a through hole formed in the bent portion 526b of the second side rail 526 and fixed to screw grooves formed in the first end member 521 and the second end member 522.

[0110] The first end member 521 extends along the stacking direction X over a first length L51 from one end side in the stacking direction X to a first position P51 that directly or indirectly contacts the battery cell 511. The first length L51 is a length that is equal to or greater than a second length (the thickness along the stacking direction of the battery cell 511) L52 of the battery cell 511 along the stacking direction X. The first length L51 may be, for example, x times or more the second length L52. x refers to a natural number.

[0111] With the above configuration, even if the total number of battery cells 511 changes, changes in the components of the battery pack 501 can be minimized.

[0112] Specifically, in the design change of the assembled battery 501, when the total number of battery cells 511 provided in the assembled battery 501 is decreased by, for example, one, the thickness of the first end member 521 can be increased by the thickness of one battery cell 511 (the second length L52) to fill the space generated in the assembled battery 501 due to the one battery cell 511 to be decreased. That is, in the design change of the assembled battery 501, when the total number of battery cells 511 provided in the assembled battery 501 is to be decreased, while changing the shape of the first end member 521 of the assembled battery 501, changes to other components of the assembled battery 501 can be avoided.

[0113] Here, one reason for decreasing the total number of battery cells 511 provided in the assembled battery 501 in the design change of the assembled battery 501 is the continuous performance improvement of the battery cells 511. That is, when, for example, 100 battery cells 511 are provided in the current version of the assembled battery 501, each time the assembled battery 501 is upgraded in the future, the number of battery cells 511 provided in one assembled battery 501 may be gradually decreased, for example, to 90, 80, 70, 60. When the number of battery cells 511 provided in one assembled battery 501 is decreased by, for example, 10 with the upgrade of the assembled battery 501, changes are also made to components of the assembled battery 501 such as the first side rail 525 and the second side rail 526. On the other hand, according to the first configuration, in any version of the assembled battery 501, during the period until the assembled battery 501 is upgraded to the next version, instead of decreasing the number of battery cells 511 by, for example, 10, minor changes can be made to decrease the number of battery cells 511 by, for example, one to several. That is, the first configuration can flexibly respond to the decrease in the number of battery cells 511 mounted on the assembled battery 501 accompanying the continuous performance improvement of the battery cells 511.

[0114] Further, according to the first configuration, by configuring the total number of battery cells 511 provided in the assembled battery 501 to be changeable, the specifications of the power that can be output from the assembled battery 501 can be diversified. The specifications are, for example, the current value of the battery cell 511. That is, according to the first configuration, without changing the outer shape of the assembled battery 501 and while minimizing the design changes of the assembled battery 501, the outputtable power can be easily changed.

[0115] Here, in the first configuration, configuring the total number of battery cells 511 provided in one assembled battery 501 to be changeable is not limited to a configuration that reduces the total number of battery cells 511, but also includes a configuration that increases the total number of battery cells 511. That is, the first configuration can minimize the change of the components of the assembled battery 501 even when the total number of battery cells 511 provided in the assembled battery 501 is increased. That is, in the first configuration, if the first length L51 of the first end member 521 is set in advance to be a length equal to or greater than the thickness (second length L52) of the battery cell 511, by shortening the first length L51 of the first end member 521, the total number of battery cells 511 can be increased.

[0116] Furthermore, the first end member 521 can be formed by injection molding using a mold. According to such a configuration, the additional processing of the mold of the first end member 521 accompanying the design change of the assembled battery 501 can be dealt with by cutting according to the thickness (second length L52) of the battery cell 511 to be reduced.

[0117] From the above, when the total number of battery cells 511 provided in the assembled battery 501 is changed (decreased or increased), the change of the components can be minimized.

[0118] The assembled battery 501 according to the sixth embodiment further has the following first configuration, second configuration, and third configuration.

[0119] <The first configuration> As shown in FIGS. 17 and 18, the first end member 521 is provided with a first screw hole 521a (an example of a fixing portion), which is fixed to a module case 700 (an example of an external fixing member) on the vehicle side via a screw 527 (an example of a fixing member). The first screw hole 521a (an example of a fixing portion) is a through hole into which the screw 527 is inserted. A screw groove for fixing the screw 527 is formed in the module case 700. The first distance D51 from the second position P52 where the first screw hole 521a is provided to the first position P51 in contact with the battery cell 511 is set to the first length L51. The first length L51 is a length equal to or greater than the thickness (second length L52) of the battery cell 511.

[0120] According to such a first configuration, when the total number of battery cells 511 provided in the assembled battery 501 is changed (decreased), the modification of the mold for forming the first end member 521 can be minimized. Specifically, the additional processing of the mold of the first end member 521 due to the design change of the assembled battery 501 only requires cutting of the mold, and no additional processing is required for changing the position of the first screw hole 521a. If it is necessary to change the position of the first screw hole as in a conventional assembled battery, it cannot be dealt with by additional processing of the mold, and in some cases, a new mold needs to be manufactured. Therefore, according to the first configuration, when the total number of battery cells 511 provided in the assembled battery 501 is changed, the change of the components of the assembled battery 501 can be minimized.

[0121] Also, in order to fix the assembled battery 501 to the module case 700 on the vehicle side, a member provided on the vehicle is fixed to the first screw hole 521a through the screw 527. However, even if the total number of battery cells 511 changes, the position of the first screw hole 521a does not need to be changed. For this reason, the design change of the position of the screw groove of the module case 700 on the vehicle side is also unnecessary. That is, according to the first configuration, the change of the module case 700 to which the assembled battery 501 is fixed is unnecessary.

[0122] The fixing portion of the first end member 521 is not limited to a through hole for inserting the screw 527. The fixing portion may be, for example, a protrusion formed on the first end member 521. In this case, the protrusion formed on the first end member 521 is hooked and fixed to the recess of the vehicle-side module case 700, or inserted and fixed.

[0123] The fixing portion of the first end member 521 is not limited to a through hole for inserting the screw 527. The fixing portion may be, for example, a screw groove formed on the first end member 521. In this case, the screw 527 inserted into the vehicle-side module case 700 is fixed to the screw groove formed on the first end member 521.

[0124] <The second configuration> As shown in FIGS. 17 and 18, the first end member 521 is provided with a second screw hole 521b (an example of a connecting portion). The first end bus bar 532 (an example of a conducting member) is connected to the second screw hole 521b by a screw 534 (an example of a fixing member). The first end bus bar 532 is a member that electrically connects the external terminal (for example, the positive terminal 511a or the negative terminal 511b) of the battery cell 511 and an external electrical device (for example, a vehicle-side power cable: not shown). The first end bus bar 532 may correspond to, for example, the negative bus bar 31b (FIG. 5). On the other hand, the bus bar 531 is a conducting member that connects the external terminals of adjacent battery cells 511. The second distance D52 along the stacking direction X from the third position P53 where the second screw hole 521b is provided to the first position P51 is set to the first length L51. The first length L51 is a length equal to or greater than the thickness (the second length L52) of the battery cell 511.

[0125] According to such a second configuration, when the total number of battery cells 511 provided in the battery pack 501 is changed (decreased), the modification of the mold for forming the first end member 521 can be minimized. Specifically, the additional processing of the mold of the first end member 521 due to the design change of the battery pack 501 only requires cutting of the mold, and no additional processing is required for changing the position of the second screw hole 521b. If it is necessary to change the position of the second screw hole as in a conventional battery pack, it cannot be dealt with by additional processing of the mold, and in some cases, new production of the mold is required. For this reason, the second configuration can minimize the change of the components of the battery pack 501 when the total number of battery cells 511 provided in the battery pack 501 is changed.

[0126] Also, a power cable (an example of an electrical device) provided in the vehicle is electrically connected to the external terminal of the battery cell 511 by the first end bus bar 532 fixed to the second screw hole 521b. However, even if the total number of battery cells 511 changes, it is not necessary to change the position of the second screw hole 521b. Therefore, it is not necessary to change the design of the joining position between the power cable on the vehicle side and the first end bus bar 532. That is, it is not necessary to change the design of the power cable on the vehicle side or the attachment method for the first end bus bar 532.

[0127] The connecting portion of the first end member 521 is not limited to the screw groove for fixing the screw 534. The connecting portion may be an insert nut embedded in the first end member 521.

[0128] Also, the positive electrode terminal 511a may be the same as the positive electrode terminal 4 (FIG. 1), and the negative electrode terminal 511b may be the same as the negative electrode terminal 5 (FIG. 1).

[0129] <The third configuration> As shown in FIGS. 17 and 18, the first end member 521 is provided with a third screw hole 521c (an example of an attachment portion). A gas discharge duct 541 (an example of an exhaust member), which exhausts the gas discharged from the gas discharge valve 511c (an example of a gas discharge portion) of the battery cell 511 to the outside, is attached to the third screw hole 521c by a screw 542 (an example of a fixing member). The third distance D53 along the stacking direction X from the fourth position P54 where the third screw hole 521c is provided to the first position P51 is set to the first length L51. The first length L51 is a length equal to or greater than the thickness (second length L52) of the battery cell 511.

[0130] According to such a third configuration, when the total number of battery cells 511 provided in the assembled battery 501 is to be changed, the change of the mold for forming the first end member 521 can be minimized. Specifically, the additional processing of the mold of the first end member 521 due to the design change of the assembled battery 501 only requires cutting of the mold, and no additional processing for changing the position of the third screw hole 521c is necessary. Therefore, the third configuration can minimize the change of the components of the assembled battery 501 when the total number of battery cells 511 provided in the assembled battery 501 is to be changed.

[0131] The attachment portion of the first end member 521 is not limited to a screw groove for fixing the screw 542. The attachment portion may be an insert nut embedded in the first end member 521.

[0132] The attachment portion of the first end member 521 is not limited to a screw groove for fixing the screw groove for fixing the screw 542. The attachment portion may be, for example, a protrusion formed on the first end member 521. In this case, the protrusion formed on the first end member 521 is hooked or inserted into the recess of the gas discharge duct 541 for fixing.

[0133] Also, the gas discharge valve 511c may be the same as the gas discharge valve 6 (FIG. 1).

[0134] The above is the description of the first to third configurations.

[0135] Incidentally, as shown in FIG. 18, the first length L51 may be set to a length equal to or greater than the sum (L52 + L53) of the second length L52 of the battery cell 511 and the third length L53 along the stacking direction X of the spacer 523. The spacer 523 is a member adjacent to the battery cell 511 along the stacking direction X, and may be the same as, for example, the spacer 21 (FIG. 3). The first length L51 may be, for example, x times or more the sum of the second length L52 and the third length L53 (x is a natural number).

[0136] As the total number of the battery cells 511 changes, the number of the spacers 523 also changes. According to such a configuration, when the total number of the battery cells 511 provided in the assembled battery 501 is changed, in addition to the change in the length (the length along the stacking direction X) associated with the number of the battery cells 511 that increases or decreases, according to the length (the length along the stacking direction X) associated with the number of the spacers 523 that increases or decreases as the number of the battery cells 511 increases or decreases, while changing the shape of the first end member 521, it is possible to avoid changing other components of the assembled battery 501.

[0137] Further, the first length L51 may be set to a length equal to or greater than twice the second length L52 of the battery cell 511. For example, as described above, the first length L51 may be x times the second length L52, but the value of x may be an integer of 2 or more. Also, as described above, the first length L51 may be, for example, x times or more the sum of the second length L52 and the third length L53, but the value of x may be an integer of 2 or more.

[0138] According to such a configuration, in particular, an increase or decrease in two or more battery cells 511 can be performed while minimizing changes in the components of the assembled battery 501.

[0139] Also, as shown in FIG. 18, the length L54 of the first end member 521 along the stacking direction X may be set to a length equal to or greater than the sum (L55 + L52) of the length L55 of the second end member 522 along the stacking direction and the length L52 of the battery cell 511 along the stacking direction.

[0140] According to such a configuration, when the total number of battery cells 511 changes, among the first end member 521 and the second end member 522, only the thickness (length L54 along the stacking direction) of the first end member 521 needs to be redesigned, and the redesign of the thickness of the second end member 522 can be made unnecessary. For this reason, when the total number of battery cells 511 changes, among the first end bus bar 532 (a member that electrically connects the external terminal of one end battery cell 511 and an external electrical device) connected to the first end member 521 and the second end bus bar 533 (a member that electrically connects the external terminal of the other end battery cell 511 and an external electrical device) connected to the second end member 522, the first end bus bar 532 needs to be changed (for example, replaced with an end bus bar of a different length), but the second end bus bar 533 does not need to be changed.

[0141] Also, as shown in FIG. 18, the assembled battery 501 may include a center member 524 (an example of a third holding member) that holds adjacent battery cells 511 between the first end member 521 and the second end member 522. That is, the center member 524 may hold the battery cell 511 adjacent to one end side and the battery cell 511 adjacent to the other end side. As shown in FIG. 18, the length L56 of the center member 524 along the stacking direction X may be set to a length equal to or greater than the length L52 of the battery cell 511.

[0142] According to such a configuration, when the total number of battery cells 511 changes, it is not necessary to redesign the thickness of at least one (preferably both) of the first end member 521 and the second end member 522, and it can be dealt with by redesigning the thickness of the center member 524. For example, the center member 524 may be a synthetic resin member formed using an injection molding die, and the additional processing of the die of the center member 524 only needs to be a cutting process according to the increase or decrease in the number of battery cells 511 and the thickness (second length L52) of the battery cell 511. For this reason, as in the modification example of the sixth embodiment shown in FIG. 19, in the assembled battery 501, not only the second end member 522 but also the first end member 521 may be a regular end member.

[0143] (Seventh Embodiment) Hereinafter, the assembled battery 502 according to the seventh embodiment of the present invention will be described. In this case, the differences from the sixth embodiment will be mainly described, and the description of the common points with the sixth embodiment will be omitted or simplified (this also applies to the description of the eighth embodiment).

[0144] FIG. 20 is a plan view showing a part of the configuration of the assembled battery 502 according to the seventh embodiment.

[0145] The first end member 21 of the assembled battery 502 according to the seventh embodiment is configured as follows. That is, as shown in FIG. 20, the first end member 21 includes an end plate portion 521P connected to a connecting member (for example, the first side rail 525 and the second side rail 526), and an end spacer portion 521Q that is separate from the end plate portion 521P and directly or indirectly contacts the battery cell 511. The fourth distance D54 along the stacking direction X of the end spacer portion 521Q is set to the first length L51. The first length L51 is a length equal to or greater than the thickness (second length L52) of the battery cell 511.

[0146] According to such a configuration, even if the total number of battery cells 511 changes, the change in components can be minimized. Specifically, even if the total number of battery cells 511 changes, it is not necessary to change the design of the end plate portion 521P connected to the connecting member, and only the design change of the thickness of the end spacer portion 521Q can be accommodated.

[0147] The end plate portion 521P is formed of, for example, metal. The end plate portion 521P may have a configuration including metal. The end spacer portion 521Q is formed of resin. The end spacer portion 521Q may have a configuration including resin. According to such a configuration, even if the total number of battery cells 511 changes, it is not necessary to change the manufacturing method of the end plate portion 521P, which is, for example, sheet metal processed.

[0148] (Eighth Embodiment) FIG. 21 is a plan view of the assembled battery according to the eighth embodiment.

[0149] As shown in FIG. 21, the assembled battery 503 according to the eighth embodiment includes a first assembled battery 501A, a second assembled battery 501B, and a bus bar 600 (an example of a conductive member) that electrically connects the first assembled battery 501A and the second assembled battery 501B. The configuration of each of the first assembled battery 501A and the second assembled battery 501B may be the same as the configuration of any of the above-described assembled batteries, for example, the configuration of the assembled battery 501 according to the sixth embodiment. That is, both the first assembled battery 501A and the second assembled battery 501B have battery cells 511, a first end member 521, and a second end member 522.

[0150] As shown in FIG. 21, the first end member 521 of the first assembled battery 501A and the first end member 521 of the second assembled battery 501B face each other along the stacking direction X.

[0151] According to this configuration, the second assembled battery 501B is located adjacent to the first assembled battery 501A along the stacking direction X, and the configuration of the second assembled battery 501B (the arrangement of the components of the second assembled battery 501B) is symmetric with the configuration of the first assembled battery 501A (the arrangement of the components of the first assembled battery 501A) along the stacking direction X. Therefore, even if the total number of battery cells 511 in the assembled battery 503 is changed, the amount of change in the center of gravity of the entire assembled battery 503 can be suppressed. For example, when 2n (n is a natural number) battery cells 511 decrease or increase from the assembled battery 503, for every two battery cells 511, one battery cell 511 is increased or decreased with respect to the first assembled battery 501A, and the other battery cell 511 is increased or decreased with respect to the second assembled battery 501B. At that time, for every two battery cells 511, the position of the battery cell 511 to be increased or decreased from the first end member 521A and the position of the battery cell 511 to be increased or decreased from the first end member 521B are made the same. As a result, the amount of change in the center of gravity of the entire assembled battery 503 can be suppressed.

[0152] Note that the assembled battery 503 (a pair of the first assembled battery 501A and the second assembled battery 501B electrically connected by the bus bar 600) may be arranged along at least one of the X, Y, and Z directions. Also, the assembled battery 503 may be expressed as a "power supply device" as in Expression 10 or Expression 11.

[0153] Further, the first end member 521 has a different weight per unit volume from the battery cell 511. In one example, the first end member 521 and the battery cell 511 have different volumes but the same weight. In this case, the change in the center of gravity of the assembled battery 503 due to the change in the total number of battery cells 511 is small. The reason is as follows. That is, if the weights of the first assembled battery 501A and the second assembled battery 501B are the same, the center of gravity of the assembled battery 503 is at the center of the assembled battery 503. In both the first assembled battery 501A and the second assembled battery 501B, the first end member 521 is closer to the center of gravity than any of the battery cells 511. Even if the total number of battery cells 511 is changed, there is no change in the position of the first end member 521, which is closest to the center of gravity, for either the first assembled battery 501A or the second assembled battery 501B. For such reasons, when the weights of the first end member 521 and the battery cell 511 are the same, the change in the center of gravity of the assembled battery 503 due to the change in the total number of battery cells 511 is small.

[0154] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the spirit of the present invention described in the claims. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Also, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Furthermore, for a part of the configuration of each embodiment, addition, deletion, or replacement with other configurations is possible. Specifically, for example, at least a part of the configuration of at least one battery pack according to the description with reference to FIGS. 17 to 21 may be applied to at least one battery pack according to the description with reference to FIGS. 1 to 16 (and the above-described Expressions 1 to 15), or at least a part of the configuration of at least one battery pack according to the description with reference to FIGS. 17 to 21 may be applied to at least one battery pack according to the description with reference to FIGS. 1 to 16 (and the above-described Expressions 1 to 15).

Explanation of Signs

[0155] 1. 511: Battery cell (single cell), 2: Battery can, 10, 10A, 10B, 10C, 10D, 10E, 100: Battery pack, 11: Block, 12, 12A: Bus bar case assembly, 21: Spacer (second spacer), 21D: Extension spacer (first spacer), 22: First end spacer (regular end member), 22a, 23a, 23Ca, 26Ab, 26Bb, 27Ab: Fixed bolt holes, 23, 23A, 23B, 23C: Second end spacer (end member), 24, 25: Side rail (side member), 26, 26A, 26B, 27, 27A: End plate (end member), 26a: Flat part, 26b, 26Aa, 26Ba, 27Aa: Fixed part, 28: Bolt, 31, 40a: Bus bar, 234: Gas discharge duct, 34: Cover, 35: Bus bar case, 40, 50: Power supply device, 521: First end member, 522: Second end member, 525: First side rail, 526: Second side rail, G0: Center of gravity (second center of gravity), G1, G2, G3, G4: Center of gravity (first center of gravity), 501, 502, 503: Battery pack, 501A: First battery pack, 501B: Second battery pack, 511: Battery cell (battery), 511a: Positive terminal (external terminal), 511b: Negative terminal (external terminal), 511c: Gas discharge valve (gas discharge part), 521:: First end member (first holding member), 521A: First end member (first holding member), 521B: First end member (first holding member), 521P: End plate part, 521Q: End spacer part, 521a: First screw hole (fixed part), 521b: Second screw hole (connecting part), 521c: Third screw hole (mounting part), 522: Second end member (second holding member), 523: Spacer, 524: Center member (third holding member), 525: First side rail (connecting member), 526: Second side rail (connecting member), 532: First end bus bar (conductive member), 541: Gas discharge duct (exhaust member), 700: Module case (external fixing member), D51: First distance, D52: Second distance, D53: Third distance, D54: Fourth distance, P51: First position, P52: Second position, P53: Third position, P54: Fourth position, X: Laminating direction of battery.

Claims

1. A plurality of stacked batteries, a first holding member that holds the plurality of batteries from one end side in the stacking direction, a second holding member that holds the plurality of batteries from the other end side in the stacking direction, a connecting member that connects the first holding member and the second holding member along the stacking direction, and having, the first holding member extends over a first length along the stacking direction to a first position that is in direct or indirect contact with the battery from the one end side, the first length is a length equal to or greater than a second length along the stacking direction, the second length is the thickness of the battery along the stacking direction, the first holding member is a member formed by injection molding using a mold, a battery pack.

2. The first holding member is provided with a fixing portion that is fixed to an external fixing member, a first distance along the stacking direction from a second position where the fixing portion is provided to the first position is set to the first length, The battery pack according to claim 1.

3. The first holding member is provided with a connecting portion to which a conducting member that electrically connects an external terminal of the battery and an external electrical device is connected, a second distance along the stacking direction from a third position where the connecting portion is provided to the first position is set to the first length, The battery pack according to claim 1 or 2.

4. The first holding member is provided with an attachment portion to which an exhaust member that exhausts gas discharged from a gas discharge portion of the battery to the outside is attached, a third distance along the stacking direction from a fourth position where the attachment portion is provided to the first position is set to the first length, The battery pack according to any one of claims 1 to 3.

5. The first holding member includes an end plate portion that is connected to the connecting member and an end spacer portion that is separate from the end plate portion and is in direct or indirect contact with the battery, a fourth distance along the stacking direction of the end spacer portion is set to the first length, The battery pack according to any one of claims 1 to 4.

6. The end plate portion contains metal, The end spacer portion contains resin, The battery pack according to claim 5.

7. having a spacer adjacent to the battery along the stacking direction, the first length is set to be equal to or greater than the sum of the second length and a third length of the spacer along the stacking direction, The assembled battery according to any one of claims 1 to 6.

8. The first length is set to be twice or more the length of the second length. The assembled battery according to any one of claims 1 to 7.

9. The first holding member of the first assembled battery and the first holding member of the second assembled battery face each other along the stacking direction. The assembled battery according to any one of claims 1 to 8.

10. The first holding member has a different weight per unit volume from that of the battery. The assembled battery according to claim 9.

11. A plurality of stacked batteries; A first holding member that holds the plurality of batteries from one end side in the stacking direction; A second holding member that holds the plurality of batteries from the other end side in the stacking direction; A connecting member that connects the first holding member and the second holding member along the stacking direction; having; The length of the first holding member along the stacking direction is set to be equal to or greater than the sum of the length of the second holding member along the stacking direction and the length of the battery along the stacking direction; The first holding member is a member formed by injection molding using a mold. Assembled battery.

12. A plurality of stacked batteries; A first holding member that holds the plurality of batteries from one end side in the stacking direction; A second holding member that holds the plurality of batteries from the other end side in the stacking direction; A connecting member that connects the first holding member and the second holding member along the stacking direction; A third holding member that holds adjacent batteries between the first holding member and the second holding member; having; The length of the third holding member along the stacking direction is set to be equal to or greater than the length of the battery along the stacking direction; The third holding member is a member made of synthetic resin formed using a mold for injection molding. Assembled battery.

13. A plurality of stacked batteries; A first holding member that holds the plurality of batteries from one end side in the stacking direction; A second holding member that holds the plurality of batteries from the other end side in the stacking direction; A connecting member that connects the first holding member and the second holding member along the stacking direction; having; The first holding member extends over a first length along the stacking direction to a first position that is in direct or indirect contact with the battery from the one end side. The first length is equal to or greater than a second length along the stacking direction, and the second length is the thickness of each of the plurality of stacked batteries. The first holding member is provided with a connecting portion to which a conducting member for electrically connecting the external terminals of the battery and an external electrical device is connected. The second distance along the stacking direction from the third position where the connecting portion is provided to the first position is set to the first length. Laminated battery. **Claim 14** A plurality of stacked batteries, A first holding member that holds the plurality of batteries from one end side in the stacking direction, A second holding member that holds the plurality of batteries from the other end side in the stacking direction, A connecting member that connects the first holding member and the second holding member along the stacking direction, and having The first holding member extends over a first length along the stacking direction from the one end side to a first position that directly or indirectly contacts the battery. The first length is a length equal to or greater than a second length along the stacking direction, and the second length is the thickness of each of the plurality of stacked batteries. The first holding member of the first laminated battery and the first holding member of the second laminated battery face each other along the stacking direction. Laminated battery.

Images