Power storage device

Abstract

To provide a power storage device capable of restricting a path of gas toward a pressure release valve.SOLUTION: A power storage device 1 includes a plurality of first power storage stacks 110, a plurality of second power storage stacks 120, a case 500, and a pressure release valve 600. The case 500 has a case body 501 and a partition wall 530. The partition wall 530 partitions the inside of the case body 501 into an accommodation chamber and a non-accommodation chamber. The partition wall 530 includes a contact end face 530a coming into contact with an inner surface of the case body 501, and an opening 530b. The pressure release valve 600 is provided at a portion, of the non-accommodation chamber, facing the opening 530b in a first direction.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to an electricity storage device. [Background technology]

[0002] For example, JP 2022-516519 A discloses a power battery pack including a plurality of cells, a battery tray that houses the cells, and a cover plate connected to the battery tray. The cells include a first group of cells and a second group of cells that are arranged in a row along the longitudinal direction of the battery tray. The first group of cells and the second group of cells are arranged at an interval along the lateral direction of the battery tray. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2022-516519 Summary of the Invention [Problem to be solved by the invention]

[0004] In the electricity storage device described in JP-A-2022-516519, it is desirable that the gas discharged from any of the electricity storage cells reaches the pressure release valve via a desired route.

[0005] An object of the present disclosure is to provide an electricity storage device that is capable of regulating the path of gas heading toward a pressure release valve. [Means for solving the problem]

[0006] An energy storage device according to one aspect of the present disclosure includes: a plurality of first energy storage stacks arranged to be aligned along a first direction; a plurality of second energy storage stacks facing the plurality of first energy storage stacks in a second direction orthogonal to both the first direction and a vertical direction and arranged to be aligned along the first direction; a case accommodating the plurality of first energy storage stacks and the plurality of second energy storage stacks; and a pressure release valve provided in the case, wherein the case includes a case main body accommodating the plurality of first energy storage stacks and the plurality of second energy storage stacks; the partition wall divides the inside of the case body into a storage chamber in which the plurality of first storage stacks and the plurality of second storage stacks are arranged, and a non-storage chamber in which the plurality of first storage stacks and the plurality of second storage stacks are not arranged, the partition wall including a contact end surface that contacts the inner surface of the case body, and an opening formed at a position facing the first direction and a space between the plurality of first storage stacks and the plurality of second storage stacks, and the pressure release valve is provided in a portion of the non-storage chamber that faces the opening in the first direction. [Effects of the Invention]

[0007] According to the present disclosure, it is possible to provide an electricity storage device that is capable of regulating the path of gas heading toward the pressure release valve. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view schematically illustrating a power storage device according to an embodiment of the present disclosure. [Figure 2] 2 is a perspective view schematically illustrating a state in which an upper cover is removed from the electricity storage device illustrated in FIG. 1. FIG. [Figure 3] FIG. 2 is a plan view schematically showing a state in which an upper cover and a cover plate are removed from the electricity storage device. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The present disclosure will be described with reference to the accompanying drawings, in which the same or corresponding elements are designated by the same reference numerals.

[0010] Fig. 1 is a perspective view that schematically shows an electricity storage device according to an embodiment of the present disclosure. Fig. 2 is a perspective view that schematically shows a state in which an upper cover is removed from the electricity storage device shown in Fig. 1. Fig. 3 is a plan view that schematically shows a state in which an upper cover and a cover plate are removed from the electricity storage device. Fig. 4 is a cross-sectional view taken along line IV-IV in Fig. 3. This electricity storage device 1 is mounted, for example, on the bottom of a vehicle.

[0011] 1 to 4, the energy storage device 1 includes a plurality of first energy storage stacks 110, a plurality of second energy storage stacks 120, a first bus bar 210, a second bus bar 220, a first junction box 310, a second junction box 320, a first electronic device 331, a second electronic device 332, a covering plate 400, a case 500, a pressure release valve 600, and a breathing membrane 700. Note that the first electronic device 331, the second electronic device 332, and the covering plate 400 are omitted from illustration in Fig. 2, and the covering plate 400 is omitted from illustration in Fig. 3.

[0012] The multiple first power storage stacks 110 are arranged side by side in a first direction. In this embodiment, the multiple first power storage stacks 110 include six first power storage stacks 110. However, the number of first power storage stacks 110 is not limited to six. Each first power storage stack 110 is formed in a rectangular parallelepiped shape that is long in a second direction that is perpendicular to both the first direction and the up-down direction.

[0013] Each first power storage stack 110 includes a plurality of power storage cells 111 (see FIG. 3). The plurality of power storage cells 111 are arranged, for example, to be aligned in a first direction. The plurality of power storage cells 111 may also be arranged to be aligned in a second direction. Each power storage cell 111 is formed in a flat rectangular parallelepiped shape. An example of each power storage cell 111 is a lithium ion battery. Each power storage cell 111 may be formed as an all-solid-state battery using a solid electrolyte. Each power storage cell 111 may include a safety valve provided at a position facing the upper cover 520, i.e., on the upper surface of the housing of the power storage cell 111.

[0014] The multiple second power storage stacks 120 are arranged to face the multiple first power storage stacks 110 in the second direction and to be aligned in the first direction. In this embodiment, the multiple second power storage stacks 120 include six second power storage stacks 120. However, the number of second power storage stacks 120 is not limited to six. The configuration of each second power storage stack 120 is the same as the configuration of the first power storage stack 110.

[0015] The first bus bar 210 connects a pair of first power storage stacks 110 adjacent to each other in the first direction. The first bus bar 210 is routed in a routing space between the plurality of first power storage stacks 110 and the plurality of second power storage stacks 120.

[0016] The second bus bar 220 connects a pair of second power storage stacks 120 adjacent to each other in the first direction. The second bus bar 220 is routed in the routing space.

[0017] The first junction box 310 is disposed at a position facing, in the first direction, a first power storage stack 110 that is disposed outermost in the first direction among the multiple first power storage stacks 110 (for example, on the front side in the front-to-rear direction of the vehicle). The first junction box 310 houses a relay, a fuse, and the like. The first junction box 310 has a first connector 312. The first connector 312 protrudes outward in the first direction.

[0018] The second junction box 320 is disposed at a position facing the second power storage stack 120 in the first direction and facing the first junction box 310 at an interval in the second direction. The second junction box 320 houses a relay, a fuse, and the like. As shown in FIG. 2 , in this embodiment, the outer shape of the second junction box 320 is larger than the outer shape of the first junction box 310. The second junction box 320 has a second connector 322. The second connector 322 protrudes outward in the first direction.

[0019] 3, the first electronic device 331 is disposed outside the first junction box 310 in the second direction. The second electronic device 332 is disposed outside the second junction box 320 in the second direction.

[0020] As shown in FIG. 4 , the covering plate 400 covers the first bus bar 210 and the second bus bar 220 from above. The covering plate 400 is disposed in a routing space between the plurality of first power storage stacks 110 and the plurality of second power storage stacks 120. The covering plate 400 extends along a first direction. The covering plate 400 is formed in a flat plate shape. The covering plate 400 is made of an insulating material. The covering plate 400 is made of, for example, mica, which is a natural inorganic mineral solidified by heat pressing. The covering plate 400 has the function of blocking gas ejected upward from any of the power storage stacks from coming into contact with the bus bars 210, 220.

[0021] The case 500 accommodates a plurality of first power storage stacks 110, a plurality of second power storage stacks 120, a first bus bar 210, a second bus bar 220, a first junction box 310, a second junction box 320, a first electronic device 331, a second electronic device 332, and a covering plate 400. The case 500 has a case main body 501 and a partition wall 530.

[0022] Case body 501 accommodates a plurality of first power storage stacks 110, a plurality of second power storage stacks 120, first bus bar 210, second bus bar 220, first junction box 310, second junction box 320, first electronic device 331, second electronic device 332, and covering plate 400. Case body 501 has a lower case 510 and an upper cover 520.

[0023] The lower case 510 is open upward and has a bottom wall 512, a peripheral wall 514, and a partition 516.

[0024] The bottom wall 512 supports each of the power storage stacks 110, 120.

[0025] The peripheral wall 514 stands upright from the peripheral edge of the bottom wall 512. The peripheral wall 514 surrounds the periphery of the plurality of first power storage stacks 110 and the plurality of second power storage stacks 120. The peripheral wall 514 is formed in a substantially rectangular cylindrical shape.

[0026] The peripheral wall 514 includes a side wall 514a formed on the side opposite (the left side in FIG. 4 ) to the side on which the plurality of first power storage stacks 110 and the plurality of second power storage stacks 120 are arranged, with the first junction box 310 and the second junction box 320 as references. The side wall 514a extends along the second direction.

[0027] The partition 516 separates the plurality of first power storage stacks 110 from the plurality of second power storage stacks 120. The partition 516 has a shape that extends along the first direction. The height of the partition 516 is lower than the height of the peripheral wall 514. As shown in FIG. 4 , a wiring space is formed between the partition 516 and the cover plate 400.

[0028] The upper cover 520, together with the lower case 510, accommodates the plurality of first power storage stacks 110, the plurality of second power storage stacks 120, the first bus bar 210, the second bus bar 220, the first junction box 310, the second junction box 320, the first electronic device 331, the second electronic device 332, and the cover plate 400. The peripheral edge of the upper cover 520 is fixed to the upper end of the peripheral wall 514 with bolts or the like. The upper surfaces of the first junction box 310 and the second junction box 320 are in contact with the upper cover 520.

[0029] The partition wall 530 is provided inside the case main body 501. The partition wall 530 faces the plurality of first power storage stacks 110 and the plurality of second power storage stacks 120 in the first direction. The partition wall 530 divides the inside of the case main body 501 into an accommodation chamber S1 and a non-accommodation chamber S2. The plurality of first power storage stacks 110 and the plurality of second power storage stacks are arranged in the accommodation chamber S1. The plurality of first power storage stacks 110 and the plurality of second power storage stacks 120 are not arranged in the non-accommodation chamber S2. The partition wall 530 extends in the second direction.

[0030] The first junction box 310 is disposed in the non-accommodation chamber S2 at a position facing the first power storage stack 110 in the first direction across the partition wall 530. The second junction box 320 is disposed in the non-accommodation chamber S2 at a position facing the second power storage stack 120 in the first direction across the partition wall 530.

[0031] As shown in FIG. 4, the partition wall 530 has a contact end surface 530a and an opening 530b.

[0032] The contact end surface 530a is in contact with the inner surface of the case body 501. The contact end surface 530a has a lower end surface 532, a side end surface 534, and an upper end surface 536.

[0033] The lower end surface 532 is connected to the bottom wall 512 by welding or the like.

[0034] The side end surface 534 is connected to the peripheral wall 514 by welding or the like.

[0035] 4, the top end surface 536 is connected to the upper cover 520 via an adhesive member 519. The top end surface 536 may also be connected to the upper cover 520 by welding or the like.

[0036] The opening 530b is formed at a position facing in the first direction a space (wiring space) between the plurality of first power storage stacks 110 and the plurality of second power storage stacks 120. In this embodiment, the partition wall 530 has a pair of defining surfaces 538 that define the opening 530b.

[0037] Each defining surface 538 is connected to the upper end surface 536. The pair of defining surfaces 538 face each other in the second direction. The pair of defining surfaces 538 are inclined gradually toward the lower end surface 532 as they approach each other.

[0038] The pressure release valve 600 is provided in the case 500. The pressure release valve 600 releases pressure inside the case 500. The pressure release valve 600 opens when the pressure inside the case 500 reaches or exceeds a reference value. The pressure release valve 600 is configured as a check valve. The pressure release valve 600 is provided in a portion of the non-housing chamber S2 that faces the opening 530b in the first direction. In this embodiment, the pressure release valve 600 is provided in a portion of the non-housing chamber S2 above the space between the first junction box 310 and the second junction box 320, i.e., in the upper cover 520.

[0039] The breathing membrane 700 is provided on the case 500. The breathing membrane 700 adjusts the pressure inside the case 500 by allowing gas to pass between the inside and outside of the case 500. The breathing membrane 700 is arranged on the opposite side of the pressure release valve 600 from the side on which the power storage stacks 110 and 120 are arranged. In this embodiment, the breathing membrane 700 is provided in a portion of the side wall 514a facing the opening 530b. Specifically, a through-hole is provided in the side wall 514a, and the breathing membrane 700 is attached to the outer surface of the side wall 514a so as to cover the through-hole. Note that the breathing membrane 700 may also be provided in a portion of the side wall 514a facing the electronic devices 331 and 332.

[0040] In the energy storage device 1 of the present embodiment described above, the contact end surface 530a of the partition wall 530 is in contact with the inner surface of the case body 501, and therefore when gas is discharged from either of the energy storage stacks 110, 120 in the accommodation chamber S1, the gas flows through the opening 530b of the partition wall 530 toward the non-accommodation chamber S2 and is then discharged to the outside of the case 500 through the pressure release valve 600 provided in the non-accommodation chamber S2. Therefore, the path of the gas toward the pressure release valve 600 is effectively restricted.

[0041] Furthermore, since the contact end surface 530a of the partition wall 530 is in contact with the inner surface of the case body 501 and the junction boxes 310, 320 are arranged between each electronic device 331, 332 and the opening 530b, the gas flowing into the non-container chamber S2 through the opening 530b is prevented from coming into contact with each electronic device 331, 332.

[0042] Furthermore, after gas is discharged from the case 500, the oxygen-containing gas (air, etc.) that has flowed into the non-container chamber S2 through the breathing membrane 700 is prevented from heading toward the container chamber S1 from areas other than the opening 530b.

[0043] It will be appreciated by those skilled in the art that the exemplary embodiments described above are examples of the following aspects.

[0044] [Aspect 1] a plurality of first power storage stacks arranged to be aligned along a first direction; a plurality of second power storage stacks that face the plurality of first power storage stacks in a second direction that is orthogonal to both the first direction and the up-and-down direction and are arranged side by side along the first direction; a case that accommodates the plurality of first power storage stacks and the plurality of second power storage stacks; a pressure release valve provided in the case, The case is a case main body that accommodates the plurality of first power storage stacks and the plurality of second power storage stacks; a partition wall provided in the case body and facing the plurality of first power storage stacks and the plurality of second power storage stacks in the first direction; the partition wall divides the inside of the case main body into an accommodation chamber in which the plurality of first power storage stacks and the plurality of second power storage stacks are arranged, and a non-accommodation chamber in which the plurality of first power storage stacks and the plurality of second power storage stacks are not arranged, The partition wall is a contact end surface that contacts the inner surface of the case body; an opening formed at a position facing a space between the plurality of first power storage stacks and the plurality of second power storage stacks in the first direction, The pressure release valve is provided in the non-container chamber at a location facing the opening in the first direction.

[0045] In this electricity storage device, the contact end face of the partition wall is in contact with the inner surface of the case body, so that gas generated from any of the electricity storage stacks in the storage chamber flows through the opening in the partition wall toward the pressure release valve provided in the non-storage chamber, effectively restricting the path of gas toward the pressure release valve.

[0046] [Aspect 2] a first junction box arranged in the non-accommodating chamber at a position facing the first power storage stack in the first direction across the partition wall; a second junction box disposed in the non-accommodating chamber, facing the second power storage stack in the first direction across the partition wall, and facing the first junction box at an interval in the second direction; 2. The power storage device according to aspect 1, wherein an upper surface of the first junction box and an upper surface of the second junction box are in contact with the case body.

[0047] In this aspect, when the internal pressure of the case body increases due to the discharge of gas from one of the power storage stacks, a gap is formed between the top surface of each junction box and the upper cover, allowing the gas to flow through the gap toward the space outside each junction box in the second direction within the non-container chamber. In other words, the space outside functions as a pressure buffer region. This prevents a sudden increase in internal pressure of the case and resulting damage to the case when gas is discharged from one of the power storage stacks.

[0048] [Aspect 3] a first electronic device disposed outside the first junction box in the second direction; The power storage device according to aspect 2, further comprising: a second electronic device disposed outside the second junction box in the second direction.

[0049] [Aspect 4] The case further includes an adhesive member that adheres the case body and the partition wall, The case body includes: a bottom wall located below the plurality of first power storage stacks and the plurality of second power storage stacks; a peripheral wall surrounding the plurality of first power storage stacks and the plurality of second power storage stacks; an upper cover that covers the plurality of first power storage stacks and the plurality of second power storage stacks, The contact end surface is a lower end surface welded to the bottom wall; a side end surface welded to the peripheral wall; an upper end surface connected to the upper cover via the adhesive member.

[0050] In this aspect, gas discharged from the electricity storage stack is prevented from reaching the non-accommodation chamber through the upper end surface of the partition wall and the gap between the upper cover.

[0051] [Aspect 5] the partition wall further includes a pair of defining surfaces each connected to the upper end surface and defining the opening; 5. The power storage device according to aspect 4, wherein the pair of defining surfaces face each other in the second direction and are inclined gradually toward the lower end surface as they approach each other.

[0052] It should be noted that the embodiments disclosed herein are illustrative in all respects and should not be considered limiting. The scope of the present invention is defined by the claims rather than the description of the above embodiments, and further includes all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0053] 1 Energy storage device, 110 First energy storage stack, 111 Energy storage cell, 120 Second energy storage stack, 210 First bus bar, 220 Second bus bar, 310 First junction box, 312 First connector, 320 Second junction box, 322 Second connector, 331 First electronic device, 332 Second electronic device, 400 Covering plate, 500 Case, 501 Case body, 510 Lower case, 512 Bottom wall, 514 Surrounding wall, 514a Side wall, 520 Upper cover, 530 Partition wall, 530a Contact end surface, 530b Opening, 532 Lower end surface, 534 Side end surface, 536 Upper end surface, 538 Defining surface, 600 Pressure release valve, 700 Breathing membrane, S1 Storage chamber, S2 Non-storage chamber.

Claims

1. a plurality of first power storage stacks arranged to be aligned along a first direction; a plurality of second power storage stacks that face the plurality of first power storage stacks in a second direction that is orthogonal to both the first direction and the up-and-down direction and are arranged side by side along the first direction; a case that accommodates the plurality of first power storage stacks and the plurality of second power storage stacks; a pressure release valve provided in the case, The case is a case main body that accommodates the plurality of first power storage stacks and the plurality of second power storage stacks; a partition wall provided in the case body and facing the plurality of first power storage stacks and the plurality of second power storage stacks in the first direction; the partition wall divides the inside of the case main body into an accommodation chamber in which the plurality of first power storage stacks and the plurality of second power storage stacks are arranged, and a non-accommodation chamber in which the plurality of first power storage stacks and the plurality of second power storage stacks are not arranged, The partition wall is a contact end surface that contacts the inner surface of the case body; an opening formed at a position facing a space between the plurality of first power storage stacks and the plurality of second power storage stacks in the first direction, The pressure release valve is provided in a portion of the non-accommodation chamber that faces the opening in the first direction.

2. a first junction box disposed in the non-accommodation chamber at a position facing the first power storage stack in the first direction across the partition wall; a second junction box disposed in the non-accommodation chamber, facing the second power storage stack in the first direction across the partition wall, and facing the first junction box at an interval in the second direction; The power storage device according to claim 1 , wherein an upper surface of the first junction box and an upper surface of the second junction box are in contact with the case body.

3. a first electronic device disposed outside the first junction box in the second direction; The power storage device according to claim 2 , further comprising: a second electronic device arranged outside the second junction box in the second direction.

4. The case further includes an adhesive member that adheres the case body and the partition wall, The case body includes: a bottom wall located below the plurality of first power storage stacks and the plurality of second power storage stacks; a peripheral wall surrounding the plurality of first power storage stacks and the plurality of second power storage stacks; an upper cover that covers the plurality of first power storage stacks and the plurality of second power storage stacks, The contact end surface is a lower end surface welded to the bottom wall; a side end surface welded to the peripheral wall; The power storage device according to claim 1 , further comprising: an upper end surface connected to the upper cover via the adhesive member.

5. the partition wall further includes a pair of defining surfaces each connected to the upper end surface and defining the opening; The power storage device according to claim 4 , wherein the pair of defining surfaces face each other in the second direction and are inclined so as to gradually approach the lower end surface as they approach each other.

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