Battery module

Abstract

To arrange a partition body easily at least partially between adjacent battery cells.SOLUTION: A battery module 10A includes a plurality of battery cells 100A, a partition plate 230A that partitions off the adjacent battery cells 100A at least partially, and a holding plate 220A to hold the partition plate 230A, and a connection plate 240A.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a battery module.

Background Art

[0002] In recent years, various battery modules have been developed. A battery module includes a plurality of battery cells.

[0003] Patent Document 1 describes a battery module. The battery module includes a plurality of cells stacked in a predetermined direction and a heat insulation buffer material located between adjacent cells.

[0004] Patent Document 2 describes a cell unit. The cell unit includes a plurality of cell groups each including a plurality of cells electrically connected to each other and a heat-resistant insulating member located between adjacent cell groups.

[0005] Patent Document 3 describes a battery module. The battery module includes a plurality of battery cells stacked in a predetermined direction. Each battery cell has a first battery cell and a second battery cell electrically connected to each other and a heat insulation member located between the first battery cell and the second battery cell.

[0006] Patent Document 4 describes an assembled battery. The assembled battery includes a plurality of single cells stacked in a predetermined direction and a spacer disposed on one end side of the plurality of single cells. At least a part of the spacer is located between electrode tabs of adjacent single cells.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Patent Document 3

[0008] As described in Patent Documents 1 to 4, a partition may be at least partially disposed between adjacent battery cells. It is desirable that the partition be easily disposed between adjacent battery cells.

[0009] An example of the object of the present invention is to easily dispose at least a partition between adjacent battery cells. Other objects of the present invention will become apparent from the description herein. [Means for Solving the Problems]

[0010] One aspect of the present invention is as follows. 1. A plurality of battery cells, a partition that at least partially partitions adjacent battery cells from each other, a holder that holds the partition, and a battery module including the same. 2. Each of the plurality of battery cells has a terminal protruding from a predetermined portion of each of the plurality of battery cells, The battery module according to 1, wherein the partition partitions the predetermined portions of adjacent battery cells from each other. 3. The battery module according to 2, wherein the partition is at least partially separated from the predetermined portions of the adjacent battery cells. 4. The battery module according to 2 or 3, wherein the partition is not at least partially located between the closest portions of the adjacent battery cells. 5. The battery module according to any one of 2 to 4, wherein the terminals are located on both sides of each of the plurality of battery cells. 6. The partition body at least partially partitions battery cells connected in series in the battery module according to any one of 1. to 5. 7. The battery module according to 6., wherein the partition body is not positioned between battery cells connected in parallel. 8. The battery module according to any one of 1. to 7., wherein the holding body holds a plurality of the partition bodies.

Advantages of the Invention

[0011] According to the above aspect of the present invention, a partition body can be easily arranged at least partially between adjacent battery cells.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Modes for Carrying Out the Invention

[0013] Hereinafter, embodiments and modified examples of the present invention will be described with reference to the drawings. In all the drawings, the same components are denoted by the same reference numerals, and the description will be omitted as appropriate.

[0014] FIG. 1 is a top view of the battery module 10A according to Embodiment 1. FIG. 2 is a front view of a part of the battery module 10A according to Embodiment 1. FIG. 3 is a schematic cross-sectional view taken along line A-A of FIG. 1.

[0015] In FIGS. 1 to 3, for the sake of explanation, the X direction, the Y direction, and the Z direction are shown. In FIG. 1, the white circle with a black dot indicating the Z direction indicates that the arrow indicated by the Z direction is directed toward the front of the paper surface. In FIG. 2, the white circle with an X indicating the X direction indicates that the arrow indicated by the X direction is directed toward the back of the paper surface. In FIG. 3, the white circle with an X indicating the Y direction indicates that the arrow indicated by the Y direction is directed toward the back of the paper surface. The X direction is the front-rear direction of the battery module 10A. The Y direction is one of the directions perpendicular to the X direction. The Y direction is the left-right direction of the battery module 10A. The Z direction is the direction perpendicular to both the X direction and the Y direction. The Z direction is the up-down direction of the battery module 10A. Hereinafter, unless otherwise specified, the directions indicated by the arrows indicating the X direction, the Y direction, and the Z direction are the front direction, the left direction, and the up direction of the battery module 10A, respectively. However, the relationships among the X direction, the Y direction, the Z direction, the front-rear direction, the left-right direction, and the up-down direction of the battery module 10A are not limited to this example.

[0016] Hereinafter, as necessary, the side toward which the arrow indicating the X direction is directed and the opposite side of the side toward which the arrow indicating the X direction is directed are referred to as the +X side and the -X side, respectively, the side toward which the arrow indicating the Y direction is directed and the opposite side of the side toward which the arrow indicating the Y direction is directed are referred to as the +Y side and the -Y side, respectively, and the side toward which the arrow indicating the Z direction is directed and the opposite side of the side toward which the arrow indicating the Z direction is directed are referred to as the +Z side and the -Z side, respectively.

[0017] As shown in FIG. 1, the battery module 10A according to Embodiment 1 includes a plurality of battery cells 100A and a pair of voltage detection devices 200A. As shown in FIGS. 1 and 3, each battery cell 100A has a battery element 110A, a positive electrode terminal 132A, a negative electrode terminal 134A, and an exterior film 140A. As shown in FIGS. 1 to 3, each voltage detection device 200A has a plurality of voltage detection units 210A, a holding plate 220A, a plurality of partition plates 230A, and a connection plate 240A. In FIG. 1, the outline of the battery element 110A of the battery cell 100A located at the end on the +Y side is illustrated by a broken line. In FIG. 1, the outline of each of the holding plate 220A and the connection plate 240A of each voltage detection device 200A is illustrated by a broken line. In FIG. 3, the outline of the battery element 110A is illustrated by a broken line.

[0018] The battery element 110A includes a positive electrode, a negative electrode, and a separator (not shown). As shown in FIGS. 1 to 3, the battery element 110A has a substantially rectangular parallelepiped shape with a length in the X direction, a width in the Z direction, and a height in the Y direction. As shown in FIG. 2, when viewed from the X direction, the battery element 110A has a substantially rectangular shape with a pair of short sides substantially parallel to the Y direction and a pair of long sides substantially parallel to the Z direction. However, the shape of the battery element 110A is not limited to this example.

[0019] As shown in FIG. 1, the positive electrode terminal 132A and the negative electrode terminal 134A are located on both sides in the X direction of each battery cell 100A. The positive electrode terminal 132A and the negative electrode terminal 134A project from a pair of sealing sides 142A located on both sides in the X direction of the battery element 110A of the exterior film 140A toward both sides in the X direction. The positive electrode terminal 132A and the negative electrode terminal 134A are electrically connected to the positive electrode and the negative electrode of the battery element 110A, respectively.

[0020] The exterior film 140A seals the battery element 110A. In one example, the exterior film 140A seals the battery element 110A together with the electrolyte. Alternatively, each battery cell 100A may be an all-solid-state battery that does not contain an electrolyte. The exterior film 140A is, for example, a laminate film. The exterior film 140A is sealed at a pair of sealing sides 142A. Hereinafter, as necessary, the sealing side 142A on the -X side is referred to as the first sealing side 142Aa, and the sealing side 142A on the +X side is referred to as the second sealing side 142Ab. As shown in FIGS. 1 and 3, the first sealing side 142Aa is drawn out from the -X side end face of the battery element 110A toward the -X side. As shown in FIG. 1, the second sealing side 142Ab is drawn out from the +X side end face of the battery element 110A toward the +X side. The exterior film 140A is also sealed at at least one other sealing side that extends in the X direction from one of the first sealing side 142Aa and the second sealing side 142Ab to the other. For example, when the exterior film 140A has two films that cover both side portions of the battery element 110A in the Y direction, the two other sealing sides are provided on both sides of the battery element 110A in the Z direction. Alternatively, when the exterior film 140A has one film that is folded back on one of the +Z side and the -Z side of the battery element 110A, the other sealing side is provided on the other of the +Z side and the -Z side of the battery element 110A.

[0021] As shown in FIGS. 1 and 2, a plurality of battery cells 100A are stacked in the Y direction. As shown in FIG. 1, the plurality of battery cells 100A include a plurality of groups of battery cells 100A connected in parallel. Hereinafter, a group of battery cells 100A connected in parallel is referred to as a parallel battery cell 100A. In the example shown in FIG. 1, the parallel battery cell 100A includes two adjacent battery cells 100A in the Y direction. The plurality of parallel battery cells 100A are connected in series in order from the parallel battery cell 100A located at one end in the Y direction to the parallel battery cell 100A located at the other end in the Y direction. As shown in FIG. 1, adjacent parallel battery cells 100A in the Y direction are connected in series via a positive electrode terminal 132A and a negative electrode terminal 134A on the +X side or -X side of the adjacent parallel battery cells 100A. As shown in FIG. 1, when viewed from the Z direction, the tip of each of the positive electrode terminal 132A and the negative electrode terminal 134A is bent at a substantially right angle with respect to the base end of each of the positive electrode terminal 132A and the negative electrode terminal 134A and overlaps with each other in the X direction. The tips of each of the positive electrode terminal 132A and the negative electrode terminal 134A are joined to each other by a joining method such as laser welding. Therefore, the positive electrode terminal 132A and the negative electrode terminal 134A are electrically connected to each other. Hereinafter, as necessary, the joined portion of the tips of the positive electrode terminal 132A and the negative electrode terminal 134A that are electrically connected to each other is referred to as a terminal joining portion 130A, the terminal joining portion 130A on the -X side is referred to as a first terminal joining portion 130Aa, and the terminal joining portion 130A on the +X side is referred to as a second terminal joining portion 130Ab.

[0022] The electrical connection of the plurality of battery cells 100A is not limited to the example according to Embodiment 1. For example, the parallel battery cell 100A may include three or more battery cells 100A connected in parallel. Alternatively, a plurality of single battery cells 100A may be connected in series in order from a single battery cell 100A located at one end in the Y direction to a single battery cell 100A located at the other end in the Y direction.

[0023] As shown in FIG. 1, a pair of voltage detection devices 200A are located on both sides of a plurality of battery cells 100A in the X direction. Hereinafter, as necessary, the plurality of voltage detection units 210A, the holding plate 220A, the plurality of partition plates 230A, and the connection plate 240A of the voltage detection device 200A on the -X side are respectively referred to as a plurality of first voltage detection units 210Aa, a first holding plate 220Aa, a first partition plate 230Aa, and a plurality of first connection plates 240Aa, and the plurality of voltage detection units 210A, the holding plate 220A, the plurality of partition plates 230A, and the connection plate 240A of the voltage detection device 200A on the +X side are respectively referred to as a plurality of second voltage detection units 210Ab, a second holding plate 220Ab, a plurality of second partition plates 230Ab, and a second connection plate 240Ab.

[0024] As shown in FIGS. 1 and 2, each voltage detection unit 210A has a substantially plate shape that is substantially perpendicular to the Z direction. Each voltage detection unit 210A is, for example, a conductor plate such as a metal plate. As shown in FIG. 1, the +X side surface of each first voltage detection unit 210Aa and the -X side surface of each first terminal joint portion 130Aa are joined to each other by a joining method such as laser welding. Therefore, each first voltage detection unit 210Aa and each first terminal joint portion 130Aa are electrically connected to each other. Therefore, the voltage of each first terminal joint portion 130Aa can be detected by each first voltage detection unit 210Aa. Each voltage detection unit 210A is electrically connected to a connector (not shown in FIGS. 1 to 3) via a voltage detection line such as a harness (not shown in FIGS. 1 to 3). The same applies to each second voltage detection unit 210Ab.

[0025] As shown in FIGS. 1 to 3, the first holding plate 220Aa has a substantially plate shape that is substantially perpendicular to the X direction. The first holding plate 220Aa is, for example, a resin plate. As shown in FIG. 2, the first holding plate 220Aa defines a plurality of openings 222A that expose a plurality of first terminal joints 130Aa. The first holding plate 220Aa integrally holds a plurality of first voltage detection units 210Aa. Therefore, by arranging the first holding plate 220Aa at an appropriate position, the plurality of first voltage detection units 210Aa can be arranged at appropriate positions with respect to the plurality of first terminal joints 130Aa. In one example, each of the first voltage detection units 210Aa and the first holding plate 220Aa are attached to each other by a mechanical connection such as a snap fit. The same applies to the second holding plate 220Ab.

[0026] As shown in FIGS. 1 to 3, each partition plate 230A has a substantially plate shape that is substantially perpendicular to the Y direction. However, the shape of each partition plate 230A is not limited to this example. As shown in FIGS. 1 and 2, each first partition plate 230Aa is located between adjacent first sealing sides 142Aa of battery cells 100A that are connected in series adjacent to each other in the Y direction. As shown in FIG. 1, the second partition plate 230Ab is located between adjacent second sealing sides 142Ab of battery cells 100A that are connected in series adjacent to each other in the Y direction. Therefore, each partition plate 230A serves as a partitioning body that at least partially partitions the sealing sides 142A of the battery cells 100A that are connected in series adjacent to each other in the Y direction.

[0027] Relatively high-temperature gas in the range of approximately 800°C to approximately 1000°C may be generated from the sealing side 142A of the battery cell 100A where an abnormality has occurred. However, in Embodiment 1, even if gas is generated from the sealing side 142A of any of the battery cells 100A, the propagation of the gas to the sealing side 142A of the battery cell 100A connected in series to the battery cell 100A and adjacent in the Y direction can be suppressed by the partition plate 230A. For example, in the example shown in FIG. 1, even if gas is generated from the sealing side 142A on the +Y side of any of the first partition plates 230Aa, the propagation of the gas to the sealing side 142A on the -Y side of the first partition plate 230Aa can be suppressed by the first partition plate 230Aa. Therefore, even if relatively high-temperature gas is generated from the sealing side 142A of any of the battery cells 100A where an abnormality has occurred, the propagation of the gas to the sealing side 142A of the other battery cells 100A connected in series to the battery cell 100A can be suppressed. Thus, in Embodiment 1, compared with the case where the partition plate 230A is not provided, the thermal runaway of the plurality of battery cells 100A can be suppressed.

[0028] In Embodiment 1, the partition plate 230A is at least partially spaced apart from the sealing sides 142A located on both sides of the partition plate 230A in the Y direction. Therefore, compared with the case where the partition plate 230A and the sealing side 142A are in contact with each other, the gas generated from the sealing side 142A can be made to flow more easily through the gap between the sealing side 142A and the partition plate 230A. However, the partition plate 230A may be in contact with at least one of the sealing sides 142A located on both sides of the partition plate 230A in the Y direction.

[0029] As described above, the partition plate 230A may be exposed to the relatively high-temperature gas generated from the battery cell 100A. Therefore, the partition plate 230A is preferably made of a material having heat resistance. For example, the partition plate 230A is made of PBT (polybutylene terephthalate).

[0030] As shown in FIGS. 1 and 3, the first holding plate 220Aa and the plurality of first partition plates 230Aa are mechanically connected to each other via the first connection plate 240Aa. The first connection plate 240Aa has a substantially plate shape that is substantially perpendicular to the Z direction. As shown in FIG. 3, the -X side end of the first connection plate 240Aa and the +Z side end of the first holding plate 220Aa are connected to each other. For example, the first connection plate 240Aa and the first holding plate 220Aa are integrally formed with each other. Alternatively, the first connection plate 240Aa and the first holding plate 220Aa may be connected to each other by a mechanical connection such as a snap fit or screwing. The +X side end of the first connection plate 240Aa and the +Z side end of each first partition plate 230Aa are mechanically connected to each other. For example, the first connection plate 240Aa and the plurality of first holding plates 220Aa are integrally formed with each other. Alternatively, the first connection plate 240Aa and the plurality of first holding plates 220Aa may be connected to each other by a mechanical connection such as a snap fit or screwing. The same applies to the second holding plate 220Ab, the plurality of second partition plates 230Ab, and the second connection plate 240Ab.

[0031] The first holding plate 220Aa and the first connection plate 240Aa serve as a holding body that integrally holds the plurality of first partition plates 230Aa. Therefore, by arranging the first holding plate 220Aa and the first connection plate 240Aa at appropriate positions, the plurality of first partition plates 230Aa can be arranged at appropriate positions with respect to the plurality of first sealing sides 142Aa. Thus, compared with the case where the first partition plate 230Aa is simply arranged without using a holding body, the first partition plate 230Aa can be easily arranged at least partially between the battery cells 100A connected in series adjacent to each other in the Y direction. The same applies to the second holding plate 220Ab, the plurality of second partition plates 230Ab, and the second connection plate 240Ab.

[0032] As shown in FIG. 1, each partition plate 230A is not at least partially located between the closest portions of adjacent battery cells 100A in the Y direction. Specifically, each partition plate 230A is not located between a portion located between a pair of sealing sides 142A of one of the adjacent battery cells 100A and a portion located between a pair of sealing sides 142A of the other of the adjacent battery cells 100A. Therefore, compared with the case where the partition plate 230A is located between the portions of the adjacent battery cells 100A, the dimension of the plurality of battery cells 100A in the Y direction can be reduced, and the volume efficiency of the battery module 10A can be improved. However, each partition plate 230A may be located between the closest portions of adjacent battery cells 100A in the Y direction.

[0033] As shown in FIG. 1, the first partition plate 230Aa is not located between the first sealing sides 142Aa of the battery cells 100A connected in parallel. In a state where the propagation of gas between the first sealing sides 142Aa of the battery cells 100A connected in series is suppressed, even if gas propagates from one of the first sealing sides 142Aa to the other of the battery cells 100A connected in parallel, the collective combustion of the plurality of battery cells 100A can be suppressed. Therefore, the first partition plate 230Aa can be made not to be located between the first sealing sides 142Aa of the battery cells 100A connected in parallel. Therefore, compared with the case where the first partition plate 230Aa is located between the first sealing sides 142Aa of the battery cells 100A connected in parallel, the first partition plate 230Aa can be easily arranged. However, the first partition plate 230Aa may be located between the first sealing sides 142Aa of the battery cells 100A connected in parallel.

[0034] The partition body that at least partially partitions adjacent battery cells 100A from each other in the Y direction is not limited to the partition plate 230A according to Embodiment 1. Further, the holding body that holds the partition body such as the partition plate 230A is not limited to the holding plate 220A and the connection plate 240A according to Embodiment 1. For example, the holding body may be a housing (not shown) that houses the plurality of battery cells 100A and the pair of voltage detection devices 200A.

[0035] FIG. 4 is a top view of a part of the battery module 10A1 according to a modification of Embodiment 1. The battery module 10A1 according to the modification is the same as the battery module 10A according to Embodiment 1, except for the following points.

[0036] In the example shown in FIG. 4, battery cells 100A connected in series adjacent to each other in the Y direction are electrically connected to each other via a bus bar 250A1. The bus bar 250A1 is electrically connected to one positive electrode terminal 132A of the battery cells 100A connected in series adjacent to each other in the Y direction and the other negative electrode terminal 134A of the battery cells 100A connected in series adjacent to each other in the Y direction.

[0037] Also in the example shown in FIG. 4, a holding plate 220A1 is provided in the same manner as in Embodiment 1. The holding plate 220A1 according to the modification holds a plurality of voltage detection parts (not shown in FIG. 4) in the same manner as the holding plate 220A according to Embodiment 1. A plurality of partition plates 230A1 are provided on the holding plate 220A1 according to the modification in the same manner as the holding plate 220A according to Embodiment 1. The holding plate 220A1 integrally holds the plurality of partition plates 230A1. The holding plate 220A1 and the plurality of partition plates 230A1 are integrally formed, for example. Alternatively, the holding plate 220A1 and the partition plates 230A1 may be formed separately and mechanically connected to each other by mechanical joining such as fitting. The plurality of partition plates 230A1 can be said to be a part of the voltage detection device. Similar to the partition plate 230A according to Embodiment 1, each partition plate 230A1 according to the modification is a partition body that at least partially partitions the sealing sides 142A of the battery cells 100A connected in series adjacent to each other in the Y direction.

[0038] FIG. 5 is a perspective view of the battery module 10B according to Embodiment 2. FIG. 6 is a perspective view of the battery cell 100B according to Embodiment 2. FIG. 7 is a side view of the battery cell 100B according to Embodiment 2. The battery module 10B according to Embodiment 2 is the same as the battery module 10A according to Embodiment 1, except for the following points.

[0039] As shown in FIG. 5, the battery module 10B according to Embodiment 2 includes a plurality of battery cells 100B, a plurality of bus bars 250B, and a pair of frame bodies 300B. As shown in FIGS. 5 to 7, each battery cell 100B has a battery element 110B, a pair of lid members 120B, a positive electrode terminal 132A, a negative electrode terminal 134A, and an exterior film 140B. In FIGS. 6 and 7, the general shape of the battery element 110B is illustrated by a dashed line. As shown in FIG. 5, each frame body 300B has an enclosing frame 310B and a plurality of partition plates 320B.

[0040] The battery element 110B includes a positive electrode, a negative electrode, and a separator (not shown). As shown in FIGS. 5 to 7, the battery element 110B has a substantially rectangular parallelepiped shape with a length in the X direction, a width in the Z direction, and a height in the Y direction. When viewed from the X direction, the battery element 110B has a substantially rectangular shape with a pair of short sides substantially parallel to the Y direction and a pair of long sides substantially parallel to the Z direction. However, the shape of the battery element 110B is not limited to this example.

[0041] As shown in FIG. 7, the pair of lid members 120B are located on both sides of the battery element 110B in the X direction. The lid member 120B on the -X side covers the end face of the battery element 110B on the -X side. The lid member 120B on the +X side covers the end face of the battery element 110B on the +X side. As shown in FIGS. 5 and 6, when viewed from the X direction, each lid member 120B has a substantially rectangular shape with a pair of short sides substantially parallel to the Y direction and a pair of long sides substantially parallel to the Z direction. As shown in FIG. 6, the dimension of each lid member 120B in the direction perpendicular to the X direction is at least partially smaller than the dimension of the battery element 110B in the direction perpendicular to the X direction. Specifically, the dimension of each lid member 120B in the Y direction and the dimension in the Z direction are smaller than the dimension of the battery element 110B in the Y direction and the dimension in the Z direction, respectively. However, the shape of each lid member 120B is not limited to this example.

[0042] As shown in FIG. 6, the positive electrode terminal 132B and the negative electrode terminal 134B are located on both sides of the battery element 110B in the X direction. The positive electrode terminal 132B and the negative electrode terminal 134B protrude from both sides of the pair of lid members 120B in the X direction. The positive electrode terminal 132B and the negative electrode terminal 134B are, for example, a conductor block or an embossed conductor plate. The positive electrode terminal 132B and the negative electrode terminal 134B are electrically connected to the positive electrode and the negative electrode of the battery element 110B, respectively.

[0043] As shown in FIGS. 6 and 7, the exterior film 140B is wound around the battery element 110B and the pair of lid members 120B around the X direction. The exterior film 140B is, for example, a laminate film. The inner peripheral surface around the X direction of the -X side end portion of the exterior film 140B and the outer peripheral surface around the X direction of the -X side lid member 120B are joined to each other by a joining method such as heat fusion. Therefore, the -X side sealing portion 142B is formed by the inner peripheral surface of the exterior film 140B and the outer peripheral surface of the -X side lid member 120B. The inner peripheral surface around the X direction of the +X side end portion of the exterior film 140B and the outer peripheral surface around the X direction of the +X side lid member 120B are joined to each other by a joining method such as heat fusion. Therefore, the +X side sealing portion 142B is formed by the inner peripheral surface of the exterior film 140B and the outer peripheral surface of the +X side lid member 120B. The exterior film 140B is also sealed at other sealing portions extending in the X direction from one of the -X side sealing portion 142B and the +X side sealing portion 142B to the other. For example, when the exterior film 140B is wound around the battery element 110B and the pair of lid members 120B once around the X direction, the surplus length portions drawn out from the wound portions of the exterior film 140B around the battery element 110B and the pair of lid members 120B are joined to each other by a joining method such as heat fusion to form other sealing portions. Hereinafter, the -X side sealing portion 142B is referred to as the first sealing portion 142Ba as necessary.

[0044] As shown in FIGS. 6 and 7, due to the dimensional differences in the Y and Z directions between the battery element 110B and each lid member 120B, the dimensions in the Y and Z directions of the portion of the exterior film 140B wound around the lid member 120B in the X direction are smaller than the dimensions in the Y and Z directions of the portion of the exterior film 140B wound around the battery element 110B in the X direction, respectively. Hereinafter, as necessary, the portion of the exterior film 140B wound around the lid member 120B on the -X side in the X direction is referred to as the narrow-width portion on the -X side of the exterior film 140B, the portion of the exterior film 140B wound around the lid member 120B on the +X side in the X direction is referred to as the narrow-width portion on the +X side of the exterior film 140B, and the portion of the exterior film 140B wound around the battery element 110B in the X direction is referred to as the wide-width portion of the exterior film 140B.

[0045] As shown in FIG. 5, the plurality of battery cells 100B are stacked in the Y direction. The plurality of battery cells 100B are connected in series in order from the battery cell 100B located at one end in the Y direction to the battery cell 100B located at the other end in the Y direction. In the example shown in FIG. 5, the adjacent battery cells 100B in the Y direction are connected in series via the bus bar 250B on the +X side or -X side of the adjacent battery cells 100B. As shown in FIG. 5, one end of the bus bar 250B in the Y direction and the positive terminal 132B of one of the adjacent battery cells 100B are joined to each other by a joining method such as laser welding. As shown in FIG. 5, the other end of the bus bar 250B in the Y direction and the negative terminal 134B of the other of the adjacent battery cells 100B are joined to each other by a joining method such as laser welding. Therefore, the positive terminal 132B, the negative terminal 134B, and the bus bar 250B are electrically connected to each other.

[0046] As shown in FIG. 5, the pair of frame bodies 300B are located on both sides in the X direction of the plurality of battery cells 100B. Hereinafter, as necessary, the surrounding frame 310B and the plurality of partition plates 320B of the frame body 300B on the -X side are referred to as the first surrounding frame 310Ba and the plurality of first partition plates 320Ba, respectively.

[0047] As shown in FIG. 5, when viewed from the X direction, the first surrounding frame 310Ba collectively surrounds the narrower-width portions on the -X side of the plurality of outer films 140B of the plurality of battery cells 100B around the X direction. As shown in FIGS. 5 and 6, a step is formed between the outer peripheral surface around the X direction of the narrower-width portion on the -X side of the outer film 140B and the outer peripheral surface around the X direction of the wider-width portion of the outer film 140B. Therefore, the outer peripheral surface around the X direction of the first surrounding frame 310Ba can be prevented from protruding outside the outer peripheral surface around the X direction of the wider-width portion of the outer film 140B. Accordingly, compared with the case where the outer peripheral surface around the X direction of the first surrounding frame 310Ba protrudes outside the outer peripheral surface around the X direction of the wider-width portion of the outer film 140B, the installation of the plurality of battery cells 100B can be easily performed. The same applies to the surrounding frame 310B of the +X side frame body 300B.

[0048] As shown in FIGS. 5 and 6, when viewed from the X direction, each first partition plate 320Ba is at least partially located between adjacent first sealing portions 142Ba of battery cells 100B that are adjacent in the Y direction and connected in series. Therefore, the first partition plate 320Ba serves as a partition body that at least partially partitions the first sealing portions 142Ba of the battery cells 100B that are adjacent in the Y direction and connected in series from each other. Thus, in the same manner as in Embodiment 1, even if relatively high-temperature gas is generated from the first sealing portion 142Ba of one of the adjacent battery cells 100B, the propagation of the gas to the first sealing portion 142Ba of the other adjacent battery cell 100B can be suppressed by the first partition plate 320Ba. The same applies to the partition plate 320B of the +X side frame body 300B.

[0049] In Embodiment 2, a gap can be formed between the first sealing portions 142Ba of the battery cells 100B adjacent in the Y direction by the narrow-width portion on the -X side of the exterior film 140B of each battery cell 100B, in which the partition plate 320B is arranged. Further, by the narrow-width portion on the -X side of the exterior film 140B of each battery cell 100B, the first partition plate 320Ba can be at least partially separated from the first sealing portions 142Ba of the adjacent battery cells 100B. Therefore, compared with the case where the first partition plate 320Ba and the first sealing portion 142Ba are in contact with each other, the gas generated from the first sealing portion 142Ba can flow more easily through the gap between the first partition plate 320Ba and the first sealing portion 142Ba. The same applies to the narrow-width portion on the +X side of the exterior film 140B and the partition plate 320B of the frame body 300B on the +X side.

[0050] In Embodiment 2, each partition plate 320B is not partially located between the closest portions of the battery cells 100B adjacent in the Y direction. Specifically, each partition plate 320B is not located between the wide-width portions of the exterior films 140B adjacent in the Y direction. Therefore, compared with the case where the partition plate 320B is located between the wide-width portions of the exterior films 140B adjacent in the Y direction, the dimensional size of the plurality of battery cells 100B in the Y direction can be reduced, and the volumetric efficiency of the battery module 10B can be improved. However, each partition plate 320B may be located between the closest portions of the battery cells 100B adjacent in the Y direction.

[0051] The first surrounding frame 310Ba serves as a holding body that integrally holds the plurality of first partition plates 320Ba. Therefore, by holding the first surrounding frame 310Ba at an appropriate position, the plurality of first partition plates 320Ba can be arranged at appropriate positions with respect to the plurality of first sealing portions 142Ba. Therefore, compared with the case where the first partition plate 320Ba is simply arranged without using a holding body, the first partition plate 320Ba can be easily arranged at least partially between the sealing portions 142B of the battery cells 100B connected in series adjacent in the Y direction. The same applies to the surrounding frame 310B of the frame body 300B on the +X side.

[0052] The partition body that at least partially separates adjacent battery cells 100B in the Y direction is not limited to the partition plate 320B according to Embodiment 2. Further, the holding body that holds the partition body such as the partition plate 320B is not limited to the surrounding frame 310B according to Embodiment 2.

[0053] FIG. 8 is a perspective view of a battery cell 100B according to a modified example of Embodiment 2.

[0054] As shown in FIG. 8, each lid member 120B may have a tapered shape. In the example shown in FIG. 8, the cross-sectional area perpendicular to the X direction of the lid member 120B on the -X side decreases as it goes toward the -X side. Similar to the example shown in FIG. 8, the cross-sectional area perpendicular to the X direction of the lid member 120B on the +X side decreases as it goes toward the +X side. In the example shown in FIG. 8, when viewed from the X direction, at the four corners of the lid member 120B, the excess length portions of the exterior film 140B around the lid member 120B in the X direction are joined to each other by a joining method such as heat fusion. Also in the example shown in FIG. 8, a gap can be formed around the lid member 120B in the X direction for arranging the surrounding frame 310B and the partition plate 320B.

[0055] FIG. 9 is a top view of a part of a battery module 10B1 according to a modified example of Embodiment 2. The battery module 10B1 according to the modified example is the same as the battery module 10B according to Embodiment 2 except for the following points.

[0056] In the example shown in FIG. 9, a holding plate 220B1 is provided in the same manner as in the first embodiment. The holding plate 220B1 according to the modification holds a plurality of voltage detection units (not shown in FIG. 9) in the same manner as the holding plate 220A according to the first embodiment. A plurality of partition plates 230B1 are provided on the holding plate 220B1 according to the modification in the same manner as the holding plate 220A according to the first embodiment. The holding plate 220B1 integrally holds the plurality of partition plates 230B1. The holding plate 220B1 and the plurality of partition plates 230B1 are integrally formed, for example. Alternatively, the holding plate 220B1 and the partition plates 230B1 may be formed separately and mechanically connected to each other by mechanical joining such as fitting. It can be said that the plurality of partition plates 230B1 are part of the voltage detection device. In the same manner as the partition plate 320B according to the second embodiment, each partition plate 230B1 according to the modification is a partition body that at least partially partitions the sealing portions 142B of the battery cells 100B connected in series adjacent to each other in the Y direction.

[0057] As described above, the embodiments and modifications of the present invention have been described with reference to the drawings. These are examples of the present invention, and various configurations other than the above can also be adopted.

Explanation of Reference Numerals

[0058] 10A, 10A1, 10B, 10B1 battery modules, 100A, 100B battery cells, 110A, 110B battery elements, 120B lid material, 130A terminal joint, 130Aa first terminal joint, 130Ab second terminal joint, 132A, 132B positive electrodes, 134A, 134B negative electrodes, 140A, 140B exterior films, 142A sealing side, 142Aa first sealing side, 142Ab second sealing side, 142B sealing part, 142Ba first sealing part, 200A voltage detection device, 210A voltage detection part, 210Aa first voltage detection part, 210Ab second voltage detection part, 220A, 220A1, 220B1 holding plates, 220Aa first holding plate, 220Ab second holding plate, 222A opening, 230A, 230A1, 230B1 partition plates, 230Aa first partition plate, 230Ab second partition plate, 240A connection plate, 240Aa first connection plate, 240Ab second connection plate, 250A1, 250B bus bars, 300B frame body, 310B surrounding frame, 310Ba first surrounding frame, 320B partition plate, 320Ba first partition plate

Claims

1. A plurality of battery cells, A partition body that at least partially separates adjacent battery cells from each other, A holding body that holds the partition body, A battery module comprising the above.

2. Each of the plurality of battery cells has a terminal protruding from a predetermined portion of each of the plurality of battery cells, The battery module according to claim 1, wherein the partition body separates the predetermined portions of adjacent battery cells from each other.

3. The battery module according to claim 2, wherein the partition body is at least partially spaced apart from the predetermined portions of the adjacent battery cells.

4. The battery module according to claim 2 or 3, wherein the partition body is not at least partially located between the closest portions of the adjacent battery cells.

5. The battery module according to claim 2 or 3, wherein the terminals are located on both sides of each of the plurality of battery cells.

6. The battery module according to any one of claims 1 to 3, wherein the partition body at least partially separates battery cells connected in series.

7. The battery module according to claim 6, wherein the partition body is not located between battery cells connected in parallel.

8. The battery module according to any one of claims 1 to 3, wherein the holding body holds a plurality of the partition bodies.

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