Power storage device

Abstract

To suppress damage of a cell unit inside of a module case when a vehicle collides at its side.SOLUTION: In a power storage device, a plurality of power storage modules 110 is disposed side by side in a lateral direction of a vehicle 1. A plurality of cell units 111 is disposed side by side in a longitudinal direction of the vehicle 1. A connection section 112 connects the plurality of cell unit 111 on both sides. A module case 113 stores therein the plurality of cell units 111 and the connection section 112. The connection sections 112 of the plurality of power storage modules 110 are disposed side by side in the lateral direction. A sidewall part 121 is positioned on one side of the plurality of power storage modules 110 in the lateral direction. A reinforcement section 125 protrudes from the sidewall part 121 toward the plurality of power storage modules 110 in the lateral direction. The reinforcement section 125 is disposed side by side in the lateral direction further with the connection section 112 of each of the plurality of power storage modules 110 disposed side by side in the lateral direction.SELECTED DRAWING: Figure 4

Description

[Technical Field]

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

[0002] Japanese Patent Application Laid-Open Publication No. 2020-142589 (Patent Document 1) discloses that a battery pack is disposed below a floor panel. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-142589 Summary of the Invention [Problem to be solved by the invention]

[0004] There is a demand for electric power storage devices (battery packs) with larger energy capacities for vehicles. To this end, electric power storage devices that include multiple module cases, each containing multiple cell units, are being considered. For example, multiple module cases can be arranged side-by-side in the left-right direction of the vehicle.

[0005] However, in a power storage device having the above configuration, there is a high possibility that the internal cell units will bend due to deformation of the module case when the vehicle is involved in a side collision, which may result in damage to the cell units.

[0006] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide an energy storage device that can prevent damage to cell units inside a module case when a vehicle is involved in a side collision. [Means for solving the problem]

[0007] An energy storage device according to an aspect of the present disclosure is an energy storage device mounted on a vehicle. The energy storage device includes a plurality of energy storage modules and a case. The plurality of energy storage modules are lined up in the left-right direction of the vehicle. The case houses the plurality of energy storage modules. Each of the plurality of energy storage modules includes a plurality of cell units, at least one connection portion, and a module case. The plurality of cell units are lined up in the front-rear direction of the vehicle. The connection portion is disposed between adjacent cell units. The connection portion connects the plurality of cell units on both sides. The module case houses the plurality of cell units and the connection portion. The connection portions of each of the plurality of energy storage modules are lined up along the left-right direction. The case includes a side wall portion and a reinforcing portion. The side wall portion is located on one side of the plurality of energy storage modules in the left-right direction. The reinforcing portion protrudes from the side wall portion along the left-right direction toward the plurality of energy storage modules. The reinforcing portion is further lined up in the left-right direction with each of the connection portions of the plurality of energy storage modules lined up in the left-right direction.

[0008] In an energy storage device according to an aspect of the present disclosure, each of the plurality of cell units preferably includes an electrode assembly, and the reinforcing portion is provided so as not to be aligned with each of the electrode assemblies in the left-right direction.

[0009] In an energy storage device according to an aspect of the present disclosure, preferably, in each of the plurality of energy storage modules, the plurality of cell units includes three or more cell units. In each of the plurality of energy storage modules, at least one connection portion includes a first connection portion and a second connection portion. The second connection portion connects at least one of the cell units connected to the first connection portion to a different cell unit. The first connection portions of each of the plurality of energy storage modules are aligned along the left-right direction. The second connection portions of each of the plurality of energy storage modules are aligned along the left-right direction. The reinforcing portion includes a first end portion that is one end in the front-rear direction and a second end portion that is the other end in the front-rear direction. The first end portion is aligned along the left-right direction with the first connection portions of each of the plurality of energy storage modules. The second end portion is aligned along the left-right direction with the second connection portions of each of the plurality of energy storage modules.

[0010] In an energy storage device according to an aspect of the present disclosure, preferably, in each of the plurality of energy storage modules, the plurality of cell units include a first cell unit, a second cell unit, a third cell unit, and a fourth cell unit. In each of the plurality of energy storage modules, a first connection portion connects the first cell unit and the second cell unit to each other. In each of the plurality of energy storage modules, a second connection portion connects the third cell unit and the fourth cell unit to each other. [Effects of the Invention]

[0011] According to the present disclosure, damage to the cell units inside the module case can be suppressed when the vehicle is involved in a side collision. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a diagram showing a vehicle equipped with a power storage device according to a first embodiment of the present disclosure. [Figure 2] 2 is a cross-sectional view of a part of the vehicle and the power storage device of FIG. 1, as viewed in the direction of the arrows along line II-II. [Figure 3] 1 is a plan view partially showing the electricity storage device according to Embodiment 1. FIG. [Figure 4] 3 is a plan view schematically showing a state of the electricity storage device according to the first embodiment when a vehicle crashes sideways. FIG. [Figure 5] FIG. 10 is a plan view partially showing an electricity storage device according to a second embodiment. [Figure 6] FIG. 10 is a plan view schematically showing a state of the electricity storage device according to the second embodiment when a vehicle is involved in a side collision. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, power storage devices according to embodiments of the present disclosure will be described with reference to the drawings. The same or corresponding parts in the drawings are designated by the same reference numerals, and description thereof will not be repeated.

[0014] In addition, the arrows F, B, U, D, L, and R in the figures used in the following explanation indicate directions based on the vehicle, with arrow F indicating "forward," arrow B indicating "backward," arrow U indicating "upward," arrow D indicating "downward," arrow L indicating "leftward," and arrow R indicating "rightward."

[0015] (Embodiment 1) Fig. 1 is a diagram showing a vehicle equipped with a power storage device according to a first embodiment of the present disclosure. Fig. 2 is a cross-sectional view of a part of the vehicle and the power storage device in Fig. 1, viewed in the direction of the arrows along line II-II. As shown in Figs. 1 and 2, the power storage device 100 according to the first embodiment of the present disclosure is a power storage device 100 equipped in a vehicle 1.

[0016] A vehicle 1 in which the power storage device 100 can be installed will be described. The vehicle 1 is, for example, an electric vehicle that can be driven by a motor, a hybrid vehicle, or the like. The vehicle 1 has a passenger compartment 2 above the power storage device 100.

[0017] The vehicle 1 may further include a floor carpet 3 and a cushioning member 4. The floor carpet 3 defines the vehicle interior 2. The cushioning member 4 is disposed below the floor carpet 3. The cushioning member 4 is lighter than metal and may be made of a material that is softer than metal. The cushioning member 4 is made of a material that includes, for example, foamed resin.

[0018] The vehicle 1 includes a vehicle frame 10. The power storage device 100 may be mounted below the vehicle frame 10. The vehicle frame 10 includes a pair of side members 11, a front member 12, and a rear member 13. The vehicle frame 10 does not necessarily include a floor panel that defines the passenger compartment 2.

[0019] The pair of side members 11 extend in the front-to-rear direction of the vehicle. The pair of side members 11 are located on either side of the center of the vehicle 1 in the vehicle width direction. The pair of side members 11 include a left side member 11L and a right side member 11R. The left side member 11L is located on the left side of the center of the vehicle 1 in the vehicle width direction. The right side member 11R is located on the right side of the center of the vehicle 1 in the vehicle width direction.

[0020] Next, a description will be given of the power storage device 100. Fig. 3 is a plan view partially showing the power storage device according to the first embodiment.

[0021] The power storage device 100 includes a plurality of power storage modules 110 and a case 120. The plurality of power storage modules 110 are arranged side by side in the left-right direction of the vehicle 1. The case 120 houses the plurality of power storage modules 110.

[0022] In this embodiment, two module groups, each made up of a plurality of power storage modules 110 lined up in the left-right direction of the vehicle 1, are housed in the case 120. The two module groups are lined up in the front-rear direction.

[0023] Each of the plurality of power storage modules 110 has a substantially rectangular parallelepiped outer shape. The longitudinal direction of each of the plurality of power storage modules 110 is along the front-to-rear direction of the vehicle 1. Each of the plurality of power storage modules 110 includes a plurality of cell units 111, at least one connection portion 112, and a module case 113.

[0024] A lithium ion battery is an example of the cell unit 111. The cell unit 111 may be configured as a so-called all-solid-state battery that includes a solid electrolyte.

[0025] Within the module case 113, multiple cell units 111 are lined up in the front-to-rear direction of the vehicle 1. There is no particular limit to the number of cell units 111 within the module case 113. Within the module case 113, the multiple cell units 111 may be further lined up in the left-to-right direction of the vehicle 1, or may be further lined up in the up-to-down direction of the vehicle 1.

[0026] Each cell unit 111 may include, for example, an electrode body 111A, a current collecting terminal 111B, and a laminate exterior body 111C.

[0027] The electrode body 111A is formed of a wound body in which a positive electrode sheet and a negative electrode sheet are wound with a separator interposed therebetween, but each electrode body 111A may also be formed of a laminate in which a positive electrode sheet and a negative electrode sheet are stacked with a separator interposed therebetween.

[0028] The current collecting terminal 111B is connected to the electrode body 111A. The current collecting terminal 111B protrudes from the electrode body 111A in the front-rear direction. The current collecting terminal 111B electrically connected to the positive electrode sheet of the electrode body 111A is made of, for example, aluminum. The current collecting terminal 111B electrically connected to the negative electrode sheet of the electrode body 111A is made of, for example, copper.

[0029] Laminated exterior body 111C houses electrode body 111A and part of current collecting terminal 111B. Laminated exterior body 111C is made of a laminate film. Current collecting terminal 111B protrudes outward in the front-to-rear direction from an edge of laminated exterior body 111C.

[0030] The connection portion 112 is disposed between adjacent cell units 111. The connection portion 112 connects the cell units 111 on both sides. Specifically, the connection portion 112 is a portion where the current collecting terminals 111B of the cell units 111 on both sides are connected to each other outside the laminated exterior body 111C.

[0031] The module case 113 houses a plurality of cell units 111 and connection parts 112. The module case 113 has a substantially rectangular parallelepiped shape and is made of stainless steel, aluminum, or an aluminum alloy.

[0032] The plurality of power storage modules 110 are arranged so that the connection portions 112 of the plurality of power storage modules 110 aligned in the left-right direction are aligned along the left-right direction.

[0033] Case 120 includes a side wall portion 121 (first side wall portion), a second side wall portion 122, a front wall portion 123, a rear wall portion 124, a reinforcing portion 125, a first inner wall portion 126, and a second inner wall portion 127. Each of the above-mentioned portions of case 120 is formed of a metal such as stainless steel or an aluminum alloy. Furthermore, each of the above-mentioned portions of case 120 may be formed integrally with one another.

[0034] The side wall portion 121 is located on one side in the left-right direction of the plurality of power storage modules 110. The second side wall portion 122 is located on the other side in the left-right direction of the plurality of power storage modules 110. The side wall portion 121 and the second side wall portion 122 extend along the front-rear direction of the vehicle 1. The side wall portion 121 and the second side wall portion 122 are fixed to the side members 11 on both sides, respectively.

[0035] The front wall portion 123 is located forward of the plurality of power storage modules 110. More specifically, the front wall portion 123 is located further forward than the front group of modules. The front wall portion 123 extends in the left-right direction of the vehicle 1. The front wall portion 123 is connected to the front ends of the side wall portion 121 and the second side wall portion 122.

[0036] The rear wall portion 124 is located rearward of the plurality of power storage modules 110. More specifically, the rear wall portion 124 is located further rearward than the rear group of modules. The rear wall portion 124 extends in the left-right direction of the vehicle 1. The rear wall portion 124 is connected to rear ends of the side wall portion 121 and the second side wall portion 122.

[0037] The reinforcing portion 125 protrudes in the left-right direction from the side wall portion 121 toward the multiple energy storage modules 110. The reinforcing portion 125 is further aligned in the left-right direction with the respective connection portions 112 of the multiple energy storage modules 110 that are aligned in the left-right direction. The reinforcing portion 125 is provided so as not to be aligned in the left-right direction with the respective multiple cell units 111 of the multiple energy storage modules 110.

[0038] In the present embodiment, the case 120 may include a plurality of reinforcing portions 125. For example, among the plurality of reinforcing portions 125, other reinforcing portions 125 different from the above-described ones may protrude in the left-right direction from the second side wall portion 122 toward the plurality of power storage modules 110.

[0039] The first inner wall portion 126 is located between the multiple power storage modules 110 and the side wall portion 121. The first inner wall portion 126 is spaced apart from the side wall portion 121. The first inner wall portion 126 extends along the front-to-rear direction of the vehicle 1. Both ends of the first inner wall portion 126 in the front-to-rear direction are connected to the front wall portion 123 and the rear wall portion 124, respectively. The first inner wall portion 126 is spaced apart from the reinforcing portion 125 extending from the side wall portion 121, but may be in contact with it.

[0040] The second inner wall portion 127 is spaced apart from the second side wall portion 122. The second inner wall portion 127 extends along the front-to-rear direction of the vehicle 1. Both ends of the second inner wall portion 127 in the front-to-rear direction are connected to the front wall portion 123 and the rear wall portion 124, respectively. The second inner wall portion 127 is spaced apart from the reinforcing portion 125 extending from the second side wall portion 122, but may be in contact with it.

[0041] The case 120 may include an upper wall portion 128 and a lower wall portion 129. The upper wall portion 128 covers the upper sides of the multiple power storage modules 110. The upper wall portion 128 may be made of, for example, carbon fiber reinforced plastics (CFRP). The upper wall portion 128 may be in contact with the buffer member 4. The lower wall portion 129 covers the lower sides of the multiple power storage modules 110. The lower wall portion 129 may have, for example, a cooling function for cooling the multiple power storage modules 110.

[0042] As described above, the energy storage device 100 according to the first embodiment of the present disclosure is an energy storage device 100 mounted on a vehicle 1. The energy storage device 100 includes a plurality of energy storage modules 110 and a case 120. The plurality of energy storage modules 110 are arranged in the left-right direction of the vehicle 1. The case 120 houses the plurality of energy storage modules 110. Each of the plurality of energy storage modules 110 includes a plurality of cell units 111, at least one connection portion 112, and a module case 113. The plurality of cell units 111 are arranged in the front-rear direction of the vehicle 1. The connection portion 112 is disposed between the plurality of adjacent cell units 111. The connection portion 112 connects the plurality of cell units 111 on both sides. The module case 113 houses the plurality of cell units 111 and the connection portion 112. The connection portions 112 of the plurality of energy storage modules 110 are arranged in the left-right direction. The case 120 includes a side wall portion 121 and a reinforcing portion 125. The side wall portion 121 is located on one side in the left-right direction of the multiple energy storage modules 110. The reinforcing portion 125 protrudes in the left-right direction from the side wall portion 121 toward the multiple energy storage modules 110. The reinforcing portion 125 is further aligned in the left-right direction with the connection portions 112 of the multiple energy storage modules 110 that are aligned in the left-right direction.

[0043] FIG. 4 is a plan view schematically illustrating the state of the energy storage device according to embodiment 1 when a vehicle is side-collided. As shown in FIG. 4, when the vehicle 1 is side-collided, the side wall 121 is pushed inward from the outside in the left-right direction. At this time, the side wall 121 bends around the portion where the reinforcing portion 125 is provided. The reinforcing portion 125 is pushed toward the energy storage module 110. Then, in the multiple energy storage modules 110 pushed into the reinforcing portion 125, the module case 113 bends around the connection portion 112 due to the above configuration. As a result, bending of the multiple cell units 111 inside the module case 113 can be suppressed. Therefore, when the vehicle 1 is side-collided, damage to the multiple cell units 111 inside the module case 113 can be suppressed.

[0044] Each of the plurality of cell units 111 includes an electrode body 111A. The reinforcing portions 125 are provided so as not to be aligned with the electrode bodies 111A in the left-right direction.

[0045] According to the above configuration, when the vehicle 1 is hit by a side collision, the module case 113 can be prevented from bending in the area housing the electrode body 111A due to the pushing of the reinforcing portion 125. This further prevents the multiple cell units 111 inside the module case 113 from being damaged.

[0046] (Embodiment 2) Next, a description will be given of an energy storage device according to a second embodiment of the present disclosure. The energy storage device according to the second embodiment differs from the energy storage device 100 according to the first embodiment mainly in the configurations of the energy storage module and the reinforcing portion. Therefore, the description of the configurations similar to those of the energy storage device 100 according to the first embodiment will not be repeated.

[0047] Fig. 5 is a plan view partially illustrating an energy storage device according to embodiment 2. As shown in Fig. 5, in an energy storage device 200 according to embodiment 2 of the present disclosure, in each of a plurality of energy storage modules 110, a plurality of cell units 111 includes three or more cell units 111.

[0048] In each of the plurality of power storage modules 110, at least one connection portion 112 includes a first connection portion 212A, a second connection portion 212B, and a third connection portion 212C.

[0049] The second connection portion 212B is connected to at least one different cell unit 111 among the cell units 111 connected to the first connection portion 212A. The first connection portions 212A of the multiple energy storage modules 110 are aligned along the left-right direction. The second connection portions 212B of the multiple energy storage modules 110 are aligned along the left-right direction. The reinforcing portion 225 includes a first end portion 225A that is one end portion in the front-rear direction, and a second end portion 225B that is the other end portion in the front-rear direction.

[0050] The first end 225A is aligned in the left-right direction with the first connection portions 212A of the power storage modules 110. The second end 225B is aligned in the left-right direction with the second connection portions 212B of the power storage modules 110.

[0051] 6 is a plan view schematically illustrating the state of the energy storage device according to embodiment 2 when a vehicle is side-collided. According to the above configuration, as shown in FIG. 6, when the vehicle 1 is side-collided, the module case 113 bends at two locations where the first connection portion 212A and the second connection portion 212B corresponding to the first end portion 225A and the second end portion 225B are located. Bending the module case 113 at two locations can suppress displacement of the multiple energy storage modules 110 in the left-right direction. Furthermore, bending the module case 113 at two locations where the first connection portion 212A and the second connection portion 212B are located can further suppress damage to the cell units 111.

[0052] More specifically, in the energy storage device 200 according to the first and second embodiments of the present disclosure, in each of the multiple energy storage modules 110, the multiple cell units 111 include a first cell unit 211A, a second cell unit 211B, a third cell unit 211C, and a fourth cell unit 211D. In each of the multiple energy storage modules 110, a first connection portion 212A connects the first cell unit 211A and the second cell unit 211B to each other. In each of the multiple energy storage modules 110, a second connection portion 212B connects the third cell unit 211C and the fourth cell unit 211D to each other.

[0053] 6, when the reinforcing portion 225 is pressed toward the energy storage module 110, the pressing force of the reinforcing portion 225 against the energy storage modules 110 can be received by the entirety of the multiple cell units 111. Specifically, this pressing force can be received by the entirety of the first cell unit 211A or the second cell unit 211B and the entirety of the third cell unit 211C or the fourth cell unit 211D. As a result, damage to the multiple cell units 111 due to bending can be further suppressed.

[0054] More specifically, the end face of the reinforcing portion 225 in the second embodiment facing the power storage module 110 extends along the front-to-rear direction of the vehicle 1. Furthermore, in each of the multiple power storage modules 110, the third connection portion 212C connects the second cell unit 211B and the third cell unit 211C. The third connection portions 212C of the multiple power storage modules 110 are also aligned along the left-to-right direction. When the reinforcing portion 225 is pushed into the multiple power storage modules 110, the second cell unit 211B and the third cell unit 211C can withstand the force.

[0055] In the above-described embodiments, configurations that can be combined may be combined with each other.

[0056] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0057] REFERENCE SIGNS LIST 1 vehicle, 2 vehicle interior, 3 floor carpet, 4 buffer member, 10 vehicle frame, 11 side member, 11L left side member, 11R right side member, 12 front member, 13 rear member, 100, 200 energy storage device, 110 energy storage module, 111 cell unit, 111A electrode body, 111B current collecting terminal, 111C laminated exterior body, 112 connection portion, 113 module case, 120 case, 121 side wall portion, 122 second side wall portion, 123 front wall portion, 124 rear wall portion, 125, 225 reinforcement portion, 126 first inner wall portion, 127 second inner wall portion, 128 upper wall portion, 129 lower wall portion, 211A first cell unit, 211B second cell unit, 211C third cell unit, 211D Fourth cell unit, 212A first connection portion, 212B second connection portion, 212C third connection portion, 225A first end portion, 225B second end portion.

Claims

1. A power storage device mounted on a vehicle, a plurality of power storage modules arranged in the left-right direction of the vehicle; a case that houses the plurality of power storage modules, Each of the plurality of power storage modules is a plurality of cell units arranged in a longitudinal direction of the vehicle; At least one connection portion disposed between the plurality of cell units adjacent to each other and connecting the plurality of cell units on both sides; a module case that houses the plurality of cell units and the connection portion, the connection portions of the plurality of power storage modules are aligned along the left-right direction, The case is a side wall portion located on one side in the left-right direction of the plurality of power storage modules; a reinforcing portion protruding from the side wall portion toward the plurality of power storage modules along the left-right direction, the reinforcing portion is further aligned in the left-right direction with the connection portions of the plurality of power storage modules aligned in the left-right direction.

2. Each of the plurality of cell units includes an electrode assembly, The power storage device according to claim 1 , wherein the reinforcing portions are provided so as not to be aligned with the electrode bodies in the left-right direction.

3. In each of the plurality of power storage modules, the plurality of cell units includes three or more cell units, In each of the plurality of energy storage modules, at least one of the connection parts includes a first connection part and a second connection part, and at least one of the cell units connected to the first connection part is connected to a different cell unit; the first connection portions of the plurality of power storage modules are aligned along the left-right direction, the second connection portions of the plurality of power storage modules are aligned along the left-right direction, the reinforcing portion includes a first end portion that is one end portion in the front-rear direction and a second end portion that is the other end portion in the front-rear direction, the first end is aligned with the first connection portions of the plurality of power storage modules in the left-right direction, The power storage device according to claim 1 , wherein the second end portion is aligned with the second connection portions of the plurality of power storage modules in the left-right direction.

4. In each of the plurality of energy storage modules, the plurality of cell units include a first cell unit, a second cell unit, a third cell unit, and a fourth cell unit; In each of the plurality of energy storage modules, the first connection portion connects the first cell unit and the second cell unit to each other, The power storage device according to claim 3 , wherein in each of the plurality of power storage modules, the second connection portion connects the third cell unit and the fourth cell unit to each other.

Images