Energy storage device

Abstract

To facilitate the connection between energy storage cells and conductive members, and to maintain these connections. [Solution] The energy storage device comprises an energy storage cell 10, a conductor member 211A, and a conductor member 211B. The energy storage cell 10 has an electrode terminal 11, insulating members 11A and 11B, an electrode terminal 12, and insulating members 12A and 12B on the same surface (surface F10). The conductor member 211A has a first portion provided on the surface of the electrode terminal 11, a second portion provided on the surface of the insulating member 11A, and a third portion located between the electrode terminal 11 and the insulating member 11A.

Description

Technical Field

[0001] The present disclosure relates to a power storage device.

Background Art

[0002] Chinese Patent Application Publication No. 116686151 (Patent Document 1) discloses a power storage device including a plurality of power storage cells fixed in a case (accommodation cavity). The electrode terminals of each power storage cell are provided facing the bottom wall of the case.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the power storage device described in Patent Document 1 above, connecting the power storage cell and the bus bar (conductive member) and maintaining their connection are not necessarily easy.

[0005] The present disclosure has been made to solve the above problems, and its object is to facilitate the connection between the power storage cell and the conductive member and the maintenance of these connections.

Means for Solving the Problems

[0006] According to one aspect of the present disclosure, a power storage device is provided. The power storage device includes a power storage cell and a conductive member. The power storage cell has an electrode terminal and a first insulating member on the same surface. The conductive member has a first portion provided on the surface of the electrode terminal, a second portion provided on the surface of the first insulating member, and a third portion located between the electrode terminal and the first insulating member.

Effects of the Invention

[0007] According to this disclosure, it becomes possible to facilitate the connection between energy storage cells and conductive members, and the maintenance of these connections. [Brief explanation of the drawing]

[0008] [Figure 1] This is a diagram illustrating the outline of an energy storage device according to an embodiment of the present disclosure. [Figure 2] This diagram shows the inside of the energy storage device according to this embodiment. [Figure 3] Figure 2 is an end view of the energy storage device along line III-III. [Figure 4] Figure 3 is a diagram illustrating the method of joining the electrode terminals and the conductor member. [Figure 5] This figure illustrates the pressure equalization device used in the method shown in Figure 4. [Figure 6] Figure 2 is a diagram illustrating the detailed configuration of each conductor component shown. [Modes for carrying out the invention]

[0009] Embodiments of this disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and their descriptions will not be repeated. In the drawings used below, the X-axis, Y-axis, and Z-axis refer to three mutually orthogonal axes. Hereafter, the direction indicated by the arrows on the X-axis, Y-axis, and Z-axis will be indicated by a "+" sign, and the opposite direction will be indicated by a "-" sign.

[0010] Figure 1 is a diagram illustrating the outline of the energy storage device according to this embodiment.

[0011] Referring to Figure 1, the energy storage device B according to this embodiment includes a lower case 100 (first housing member), an upper cover 110 (second housing member), and a shear panel 120 (third housing member), which function as the housing of the energy storage device B. The lower case 100 opens upward (towards the +Z side) and houses a plurality of energy storage cells and various components related to these energy storage cells. As will be described in detail later, the lower case 100 houses the energy storage cells, a cooler, and a junction box (hereinafter referred to as "J / B") (see Figure 2). The upper cover 110 is positioned above the lower case 100 and functions as a lid for the lower case 100. The shear panel 120 is positioned below the lower case 100 (towards the -Z side) and suppresses impacts to the lower case 100 due to road surface interference. An exhaust passage is also formed between the lower case 100 and the shear panel 120.

[0012] When the energy storage device B is mounted on the vehicle, for example, the -Z side is downward (downward in the vertical direction), the +Z side is upward (upward in the vertical direction), the -X side is the front of the vehicle, and the +X side is the rear of the vehicle. The energy storage device B may function as a drive energy storage device, commonly referred to as a "battery pack". The vehicle may be an electric vehicle (BEV) or another electric vehicle (xEV).

[0013] The lower part of Figure 1 shows a view of the lower case 100 in an empty state (nothing contained inside) as seen from above (+Z side). The lower case 100 has a bottom wall 101 (bottom) and a peripheral wall 102 (periphery). The bottom wall 101 includes regions D1 to D5. The peripheral wall 102 includes side walls W1 to W4. Side walls W1, W2, W3, and W4 correspond to the -X side, +X side, -Y side, and +Y side ends of the lower case 100, respectively. Side wall W2 includes side walls W21 to W23. Brackets 121 and 122 are provided on side walls W21 and W23, respectively. Discharge valves 151 and 152 are provided on side wall W22. Side wall W22 is connected to side walls W3 and W4 via side walls W21 and W23, respectively. Brackets 131 and 132 are provided on side walls W3 and W4, respectively. Brackets 111 and 112 are provided on side wall W1. The energy storage device B is connected to the vehicle body (e.g., floor panel) by fastening each bracket to, for example, the floor member of the vehicle.

[0014] The bottom wall 101 is provided with partition walls 103 and 104 extending in the Y direction. Partition wall 104 is located on the +X side of partition wall 103. Region D5 is a rectangular area located in the center of the lower case 100 and is partitioned by partition walls 103 and 104. Region D5 is the area where the wiring board 200 and energy storage stacks S1 to S6 (see Figure 2), which will be described later, are arranged. Region D5 is located between partition walls 103 and 104.

[0015] In region D5, openings h1 are formed at the positions where each energy storage cell is placed. Each of the multiple openings h1 is positioned in the Z direction to face the valve 13 of the energy storage cell 10 (see Figure 3), which will be described later. Multiple openings h1 are arranged in the X direction to form rows of openings h1. A number of rows corresponding to the energy storage stack are formed in the bottom wall 101. The openings h1 are, for example, elongated holes that penetrate the bottom wall 101. However, the shape of the openings h1 can be changed as appropriate. The openings h1 are formed, for example, by punching.

[0016] In this embodiment, cover members 141 to 146 are provided in region D5 of the bottom wall 101. As a result, all openings h1 formed in the bottom wall 101 are covered by the cover members 141 to 146. Each of the cover members 141 to 146 comprises a base material 105 that is elongated in the X direction and N lid portions 105a arranged in the X direction. In this embodiment, the number of energy storage cells included in one energy storage stack is also N. N is, for example, 20 or more and 50 or less. However, it is not limited to this, and N may be 2 or more and less than 20, or it may be more than 50.

[0017] The base material 105 may have an adhesive on one side (the adhesive side). The base material 105 may be an adhesive tape, such as a PP (polypropylene) tape. N lid portions 105a are formed on the base material 105. In this embodiment, the lid portions 105a contain mica. The N lid portions 105a in the cover members 141, 142, 143, 144, 145, and 146 are each formed to cover the opening h1 located below the energy storage stacks S1, S2, S3, S4, S5, and S6 (see Figure 2), which will be described later. The size of the lid portion 105a is the same as or larger than the opening h1. For example, N lid portions 105a may be formed on the base material 105 by attaching N mica foils to the adhesive surface of the base material 105. Alternatively, N lid portions 105a may be formed on the base material 105 by forming N through holes in the base material 105 and providing mica foil in each of these through holes. The cover members 141 to 146 are attached, for example, to the upper surface (+Z side) of the bottom wall 101 via the adhesive surface of the base material 105.

[0018] On the -Y side and +Y side of the region D5, a region D3 and a region D4 are provided respectively. A region D1 is provided outside (-X side) of the partition wall 103. A region D2 is provided outside (+X side) of the partition wall 104. The region D2 is a region where the battery circuit unit 30 (Fig. 2) is arranged. The region D2 is located at the +X side end of the lower case 100 and is partitioned by the partition wall 104 and the side wall W2. In this embodiment, each of the bottom wall 101, the peripheral wall 102, and the partition walls 103, 104 is formed of metal. However, these materials can be changed as appropriate.

[0019] Fig. 2 is a view looking down from above the inside of the lower case 100 (inside the power storage device B) with the upper cover 110 removed. Referring to Fig. 2, between the lower case 100 and the upper cover 110, power storage stacks S1 to S6, a cooling device 20, a battery circuit unit 30, and a wiring board 200 are accommodated. Each of the power storage stacks S1 to S6 includes N power storage cells 10 arranged in the X direction. Details of the configuration of each power storage cell will be described later. The wiring board 200 has a wiring pattern for the power storage stacks S1 to S6. The battery circuit unit 30 includes a circuit electrically connected to the power storage stacks S1 to S6. The battery circuit unit 30 may be a single unit or may include a plurality of units.

[0020] The cooling device 20 includes ports 20A, 20B, pipes 21A, 21B extending in the Y direction, pipes 22A, 22B extending in the X direction, a plurality of coolers 22C extending in the Y direction, and a cooling pipe 23. These are connected in order from the upstream side as the port 20A, the pipe 21A, the pipe 22A, the cooling pipe 23, the pipe 22B, the pipe 21B, and the port 20B. Also, the pipe 22A and the pipe 22B are connected via a plurality of coolers 22C (cooling plates) arranged in the X direction. Between adjacent power storage cells in the power storage stacks S1 to S6, a cooler 22C is arranged. Those adjacent power storage cells are cooled by the refrigerant flowing through the flow path formed inside the cooler 22C. The cooler 22C has a flow path communicating with each of the pipes 22A, 22B. The cooling pipe 23 is configured to cool the battery circuit unit 30.

[0021] Referring to FIGS. 1 and 2, ports 20A and 20B are provided on the side wall W1. Port 20B is located on the +Y side of port 20A. Pipes 21A and 21B are arranged in region D1. Pipes 22A and 22B are arranged in region D3 and region D4 respectively. Cooling pipe 23 is arranged in region D2. A plurality of coolers 22C are arranged in region D5. The refrigerant supplied from port 20A to pipe 21A flows in pipe 21A toward the -Y side. The refrigerant flowing from pipe 21A into pipe 22A flows in pipe 22A toward the +X side toward cooling pipe 23 and also flows into each flow path of the plurality of coolers 22C. The refrigerant flowing from pipe 22A into cooler 22C flows toward pipe 22B on the +Y side while cooling the power storage stacks S1 to S6. Also, the refrigerant flowing from pipe 22A into cooling pipe 23 flows toward pipe 22B on the +Y side while cooling the battery circuit unit 30. The refrigerant flowing from cooler 22C or cooling pipe 23 into pipe 22B flows in pipe 22B toward pipe 21B on the -X side. Thereafter, the refrigerant flows in pipe 21B toward the -Y side and flows out from port 20B. The refrigerant may be a liquid (such as water, oil, antifreeze, etc.) or a gas.

[0022] In this embodiment, a wiring board 200 is arranged on the +Z side of the bottom wall 101, and power storage stacks S1 to S6 are further arranged on the +Z side of the wiring board 200.

[0023] Figure 3 is an end view of the energy storage device B along line III-III in Figure 2. As shown in the perspective view on the left side of Figure 3, the energy storage cell 10 comprises a case 10a and an electrode body 10b housed in the case 10a. The case 10a is a rectangular case in the shape of a rectangular parallelepiped. The electrode body 10b may include one or more windings (for example, two windings). The windings have a structure in which, for example, a positive electrode sheet and a negative electrode sheet are wound with a separator in between. Each of the positive electrode sheet and the negative electrode sheet includes an electrode foil and an active material layer. The energy storage cell 10 is a secondary battery such as a lithium-ion battery, nickel-metal hydride battery, or sodium-ion battery. In this embodiment, a liquid-type lithium-ion battery is used as the energy storage cell 10. The case 10a houses the electrolyte together with the electrode body 10b. The type of secondary battery is arbitrary, and for example, it may be an all-solid-state secondary battery. Instead of a wound structure, a laminate (for example, a laminate in which a positive electrode sheet and a negative electrode sheet are laminated with a separator in between) may be used.

[0024] The energy storage cell 10 has electrode terminals 11 and 12, insulating members 11A, 11B, 12A, and 12B, and a valve 13 on the same plane. Specifically, the electrode terminals 11 and 12, insulating members 11A, 11B, 12A, and 12B, and the valve 13 are provided on the surface F10 (vertically downward-facing surface) of the case 10a. The valve 13 functions as an exhaust valve. The case 10a is basically maintained in a sealed state. However, if the pressure inside the case 10a exceeds a first reference value, the valve 13 opens to reduce the pressure inside the case 10a. Also, the electrode terminals 11 and 12 are electrically connected to the positive electrode sheet and negative electrode sheet of the electrode body 10b, respectively, and function as positive and negative electrode terminals. The parts of the case 10a surrounding the electrode terminals 11 and 12 may be made of insulating material, and the other parts may be made of metal. However, the material of the case 10a is arbitrary. In this embodiment, the electrode terminal 11, insulating member 11A, and insulating member 11B correspond to examples of the "electrode terminal," "first insulating member," and "second insulating member" according to this disclosure, respectively.

[0025] In this embodiment, each energy cell included in the energy storage stacks S1 to S6 has the same configuration (the configuration shown in Figure 3). By forming the energy storage stacks S1 to S6 using a common energy storage cell 10, the manufacturing of the energy storage device B becomes easier and manufacturing costs can be reduced. However, this is not limited to this, and each energy storage stack may include multiple types of energy storage cells. Also, the number of energy storage stacks can be changed as appropriate. The number of energy storage stacks may be one or more.

[0026] Each energy cell in the energy storage stack S1 to S6 is electrically connected by the wiring pattern on the wiring board 200. An example of a wiring pattern is shown at the bottom of Figure 2.

[0027] Specifically, the wiring board 200 comprises a rectangular substrate 201, a plurality of conductor members 211, a plurality of conductor members 212, a plurality of conductor members 213, a plurality of conductor members 214, a plurality of conductor members 215, a plurality of conductor members 216, conductor members 221 to 223, and conductor members 231 to 236. The substrate 201 is formed of an insulating material (e.g., resin) and has insulating properties.

[0028] Each of the multiple conductor members 211 electrically connects the energy cells included in the energy storage stack S1. Each of the multiple conductor members 212 electrically connects the energy cells included in the energy storage stack S2. Each of the multiple conductor members 213 electrically connects the energy cells included in the energy storage stack S3. Each of the multiple conductor members 214 electrically connects the energy cells included in the energy storage stack S4. Each of the multiple conductor members 215 electrically connects the energy cells included in the energy storage stack S5. Each of the multiple conductor members 216 electrically connects the energy cells included in the energy storage stack S6.

[0029] Conductor member 221 electrically connects energy storage stacks S1 and S2. Conductor member 222 electrically connects energy storage stacks S3 and S4. Conductor member 223 electrically connects energy storage stacks S5 and S6. Conductor members 231, 232, 233, 234, 235, and 236 electrically connect energy storage stacks S1, S2, S3, S4, S5, and S6 to the battery circuit unit 30, respectively.

[0030] The wiring pattern is formed by the conductor members described above. Each of the conductor members 211-216, 221-223, and 231-236 may be a metal busbar. Each conductor member has a linear (e.g., straight or U-shaped) planar shape connecting the electrode terminals, as shown in Figure 2. The cross-sectional structure of each conductor member will be described later (see Figures 3-6).

[0031] The wiring board 200 is electrically connected to the battery circuit unit 30. The battery circuit unit 30 includes a total positive terminal 31, a total negative terminal 32, a J / B 33, a fuse 34, and wires L1 to L4. The total positive terminal 31 is located at the positive terminal end of the entire energy storage device B (all energy storage cells). The total negative terminal 32 is located at the negative terminal end of the entire energy storage device B. Wire L1 electrically connects conductor member 232 and conductor member 233. Wire L2 electrically connects conductor member 234 and conductor member 235. A fuse 34 is provided on wire L2. Conductor member 236 is connected to the total positive terminal 31. Wire L3 electrically connects the total positive terminal 31 and J / B 33. Conductor member 231 is connected to the total negative terminal 32. Wire L4 electrically connects the total negative terminal 32 and J / B 33. J / B33 houses various electrical devices. J / B33 may include at least one of a relay, fuse, resistor, current sensor, and connector (e.g., a connector to an on-board charger). The battery circuit unit 30 may further include at least one of a BMS (Battery Management System) and an ECU (Electronic Control Unit).

[0032] An opening may be formed in the partition wall 104 for passing the conductor members 231 to 236 through. Alternatively, a wire (e.g., a cable) connected to the wiring board 200 may be connected to the battery circuit unit 30 by passing over the partition wall 104. Note that partition walls 103 and 104 are not essential components. At least one of partition walls 103 and 104 may be omitted.

[0033] In the energy storage stacks S1 to S6, "6 × N" energy storage cells 10 are arranged in a matrix with 6 rows in the Y direction and N rows in the X direction. In the wiring pattern shown in Figure 2, multiple parallel connections are connected in series. The N energy storage cells 10 are arranged so that the positional relationship between the electrode terminals 11 (positive terminal) and electrode terminals 12 (negative terminal) is reversed every two cells. Each of the conductor members 211 to 216 connects two energy storage cells in parallel in the corresponding energy storage stack, and the resulting parallel connections (multiple energy storage cells connected in parallel) are connected in series. The connection configuration of the multiple energy storage cells can be changed as appropriate. For example, the number of energy storage cells connected in parallel may be three or more, instead of two. Alternatively, all energy storage cells may be connected in series without forming parallel connections.

[0034] In the substrate 201, openings h2, as shown in Figure 3, are formed at the same positions as opening h1 (Figure 1) in the XY plane. Each of the same number of openings h2 (6 × N) as opening h1 faces the valve 13 of the energy storage cell 10 in the Z direction. Openings h2 are, for example, elongated holes that penetrate the substrate 201. Openings h2 have larger dimensions than openings h1 in the XY plane. In the XY plane, opening h1 is located inside opening h2. As shown in Figure 3, each opening h2 is connected to opening h1 via a cover portion 105a.

[0035] In the manufacturing of the energy storage device B, for example, the processes shown in Figures 4 to 6, described later, are performed to form a wiring board 200 on which the energy storage stacks S1 to S6 are mounted. The energy storage stacks S1 to S6 are mounted on the wiring board 200 with the surface F10 of each energy storage cell facing downward in the vertical direction. The wiring board 200 is then placed inside the lower case 100, and the battery circuit unit 30 is connected to the wiring board 200. Furthermore, the cooling device 20 is placed inside the lower case 100. As a result, the inside of the lower case 100 is in the state shown in Figure 2. Of the cooling device 20, the cooler 22C may be placed inside the lower case 100 together with the energy storage stacks S1 to S6. After that, the remaining part of the cooling device 20 may be placed inside the lower case 100, and the pipes 22A and 22B may be connected to the cooler 22C. Each of the wiring board 200 and the battery circuit unit 30 may be fixed to the lower case 100 with an adhesive (for example, silicone adhesive).

[0036] As shown in Figure 3, the upper cover 110 is joined to the upper surface (+Z side) of each of the side walls W1 to W4 (only side wall W3 is shown in Figure 3) via, for example, adhesive 110b, and further fastened with bolts 110a. In addition, the shear panel 120 is joined to the lower surface (-Z side) of each of the side walls W1 to W4 via, for example, adhesive 120b. Although not shown in Figure 3, the piping 22A shown in Figure 2 is located in the space V3 between the energy storage cell 10 located at the -Y end of the lower case 100 and the side wall W3.

[0037] An exhaust passage P1 is formed between the bottom wall 101 of the lower case 100 and the shear panel 120. Each of the side walls W1 to W4 is formed in a hollow shape. An exhaust passage P3 is formed inside side wall W3. Although not shown, exhaust passages are also formed inside side walls W2 and W4 in a manner similar to the exhaust passage P3 of side wall W3. These exhaust passages are in communication with each other. In addition, exhaust holes connected to discharge valves 151 and 152 (Figure 2) are formed in side wall W2. These exhaust holes are in communication with the exhaust passages.

[0038] When the internal pressure of the energy storage cell 10 exceeds a first reference value, valve 13 opens as shown in Figure 3. Then, the pressure and heat of the gas discharged from inside the energy storage cell 10 through valve 13 create a hole in the cover portion 105a facing valve 13. The gas discharged from the energy storage cell 10 flows into the exhaust passage P1 through this hole. Each of the discharge valves 151 and 152 shown in Figure 2 opens when the pressure in the exhaust passage exceeds a second reference value. The second reference value may be a pressure value lower than the first reference value. For example, check valves are used for each of the discharge valves 151 and 152. When at least one of the discharge valves 151 and 152 opens, the gas in each exhaust passage flows toward the opened discharge valve and is discharged to the outside of the energy storage device B through that valve. The thickness of the lid portion 105a provided on the lower case 100 (Figure 1) is set to a thickness such that a hole is created when the opposing valve 13 opens (for example, when the valve opens in a manner that causes ignition).

[0039] A mica layer 120a (for example, mica foil) is provided on the inner (+Z side) surface of the shear panel 120. The mica layer 120a may be provided so as to overlap all of the cover portions 105a in the XY plane. The mica layer 120a protects the shear panel 120 from substances (gas, electrolyte, debris, etc.) released from the energy storage cell 10 through the cover portions 105a.

[0040] The structure of the conductor member 211 will be described below as a representative example. However, in this embodiment, conductor members 212 to 216 also have a structure similar to that of conductor member 211. In Figure 3, of the two conductor members 211 (see Figure 2), the conductor member 211 on the -Y side is labeled as "conductor member 211A," and the conductor member 211 on the +Y side is labeled as "conductor member 211B."

[0041] As shown in Figure 3, the conductor members 211A and 211B are crimped to the sides (XZ planes) of the electrode terminals 11 and 12 by a force in the Y direction, respectively. Each of the electrode terminals 11 and 12 is formed in the shape of a rectangular parallelepiped. Each of the electrode terminals 11 and 12 has a longer dimension in the X direction than in the Y direction. This increases the contact area between electrode terminal 11 and conductor member 211A, and the contact area between electrode terminal 12 and conductor member 211B.

[0042] An insulating member 11A is placed on the +Y side (inside) of electrode terminal 11. An insulating member 11B is placed on the -Y side (outside) of electrode terminal 11. An insulating member 12A is placed on the -Y side (inside) of electrode terminal 12. An insulating member 12B is placed on the +Y side (outside) of electrode terminal 12. Each of the insulating members 11A, 11B, 12A, and 12B is formed in the shape of a rectangular parallelepiped. Each of the insulating members 11A, 11B, 12A, and 12B has a longer dimension in the X direction than in the Y direction. Each of the insulating members 11A and 11B may be placed parallel to electrode terminal 11 and may have the same dimensions as electrode terminal 11 in the X, Y, and Z directions. Each of the insulating members 12A and 12B may be placed parallel to electrode terminal 12 and may have the same dimensions as electrode terminal 12 in the X, Y, and Z directions.

[0043] The insulating member 11A is located between the electrode terminal 11 and the valve 13. The insulating member 12A is located between the electrode terminal 12 and the valve 13. Each of the insulating members 11A and 12A may act to protect the electrode terminal 11 or 12 from the high-temperature exhaust gas discharged from the valve 13. Each of the insulating members 11A and 12A may also guide the discharged exhaust gas to the openings h1 and h2. Each of the insulating members 11A, 11B, 12A, and 12B may be formed from a thermosetting resin.

[0044] Grooves are formed on both the +Y side (specifically, between the electrode terminal 11 and the insulating member 11A) and the -Y side (specifically, between the electrode terminal 11 and the insulating member 11B) of the electrode terminal 11. The conductor member 211A is plastically deformed to fit into these grooves. The portion of the conductor member 211A that fits into each groove is in contact with the surface F10 of the energy storage cell 10.

[0045] Grooves are formed on the -Y side (specifically, between the electrode terminal 12 and the insulating member 12A) and the +Y side (specifically, between the electrode terminal 12 and the insulating member 12B) of the electrode terminal 12. The conductor member 211B is plastically deformed to fit into these grooves. The portion of the conductor member 211B that fits into each groove is in contact with the surface F10 of the energy storage cell 10.

[0046] The -Z-side ends of the conductor members 211A and 211B are housed in recesses R1A and R1B formed in the substrate 201, respectively. Figure 4 is a diagram illustrating the method of joining the electrode terminals and the conductor members. Figure 4 shows the electrode terminal 11 and the conductor member 211A, but the electrode terminal 12 and the conductor member 211B can be joined in the same manner.

[0047] The crimping device 500 comprises a support portion 501, a biasing member 502 (e.g., a spring member) connected to the support portion 501, a pad 510, and cams 511 and 512. The pad 510 is connected to the support portion 501 via the biasing member 502. The biasing member 502 is configured to be expandable and contractible in the Z direction. The support portion 501 functions as a cam driver for each of the cams 511 and 512. The cams 511 and 512 function as cam sliders that slide toward the +Y side and the -Y side, respectively. The cams 511 and 512 each have protrusions 511a and 512a that project toward the +Z side, respectively. The support portion 501 has a restricting portion P51 that projects toward the -Y side and a restricting portion P52 that projects toward the +Y side. When the biasing member 502 is not retracted, the restricting portions P51 and P52 contact the cams 511 and 512, respectively.

[0048] In the first step, a flat conductive member E10 is placed on the electrode terminal 11 and insulating members 11A and 11B. A groove R51 is formed between the electrode terminal 11 and the insulating member 11B. A groove R52 is formed between the electrode terminal 11 and the insulating member 11A. The protrusions 511a and 512a are arranged to face the grooves R51 and R52, respectively, in the Z direction. The insulating member 11A faces the first side surface (+Y side surface) of the electrode terminal 11 and has a slope F1 (first slope) that approaches the first side surface as it approaches the base end (surface F10) of the electrode terminal 11. The insulating member 11B faces the second side surface (-Y side surface) of the electrode terminal 11 and has a slope F2 (second slope) that approaches the second side surface as it approaches the base end (surface F10) of the electrode terminal 11. In the first step, the crimping device 500 is displaced to the +Z side so that the pad 510 and the cams 511 and 512 move closer to the conductive member E10.

[0049] In the second step, the pad 510 and cams 511 and 512 are pressed against the surface (-Z side) of the conductor member E10, and a force is applied to the +Z side. The conductor member E10 is pressed to the +Z side by the pad 510 and cams 511 and 512, and is joined to the upper surface (-Z side) of the electrode terminal 11, and undergoes plastic deformation to fit into the grooves R51 and R52, respectively. At this time, the sliding movement of the cams 511 and 512 in the Y direction is restricted by the restricting portions P51 and P52 of the pad 510, respectively. However, because the insulating members 11A and 11B have inclined surfaces F1 and F2, respectively, the conductor member E10 plastically deforms toward the electrode terminal 11 according to the inclined surfaces F1 and F2. This increases the degree of contact between the electrode terminal 11 and the conductor member E10.

[0050] In the third step, with the pad 510 in contact with the conductor member E10, a further force is applied to the crimping device 500 in the +Z direction. This causes the biasing member 502 to contract until its length in the Z direction is less than or equal to a predetermined value, and the restricting portions P51 and P52 of the pad 510 separate from the cams 511 and 512, respectively. As a result, the restriction by the pad 510 is released, and the cam 511 applies a force to the conductor member E10 in the +Y direction, while the cam 512 applies a force to the conductor member E10 in the -Y direction. This causes the conductor member E10 to be joined to the side surfaces (the -Y side and the +Y side) of the electrode terminal 11, and the conductor member E10 becomes the conductor member 211A.

[0051] As described above, by applying a force in the Z direction to the conductor member in the second step and a force in the Y direction to the conductor member in the third step, it becomes easier to apply forces of appropriate magnitude to the conductor member in both the Z and Y directions. In addition, in the third step, an inward force is applied to two parts of the conductor member E10 located outside the electrode terminal 11 (the parts that fit into grooves R51 and R52, respectively), and the electrode terminal 11 is sandwiched between these two parts. This increases the bonding strength between the electrode terminal 11 and the conductor member 211A. In the example shown in Figure 4, the second and third steps are performed by a single device (crimping device 500). However, the second and third steps may be performed separately by different devices.

[0052] In this embodiment, the pressure equalization device 600 shown in Figure 5 is used to apply force evenly to the conductor members provided at each electrode terminal, thereby joining the conductor members to each electrode terminal with uniform pressure. Figure 5 is a diagram illustrating the pressure equalization device 600.

[0053] Referring to Figure 5, the pressure equalizer 600 comprises an oil supply device 610, piping 620, a check valve 620a, and a plurality of hydraulic cylinders 630. A hydraulic cylinder 630 is provided for each electrode terminal, and a crimping device 500 is attached to each hydraulic cylinder 630. Specifically, the hydraulic cylinder 630 is provided on the -Z side end face of the support portion 501 of the crimping device 500. Each of the plurality of hydraulic cylinders 630 receives oil from a common oil supply device 610 and pressurizes the support portion 501 of the corresponding crimping device 500 to the +Z side. The oil supply device 610 and the plurality of hydraulic cylinders 630 are interconnected via a common piping 620. The oil supply device 610 supplies oil to each hydraulic cylinder 630 through the piping 620 until a predetermined hydraulic pressure is applied to each hydraulic cylinder 630. A check valve 620a provided in the piping 620 maintains the hydraulic pressure to each hydraulic cylinder 630 at a predetermined pressure. This ensures that an equal amount of hydraulic pressure is applied to each hydraulic cylinder 630. By using the pressure equalizer 600 to perform the first to third steps described above (Figure 4), the conductor member E10 can be crimped with equal pressure to each of the electrode terminals 11 and 12 of all the energy storage cells included in the energy storage stacks S1 to S6.

[0054] By the method described above, the conductor members 211 to 216 are attached to the energy storage stacks S1 to S6, respectively. By fixing these energy storage stacks S1 to S6 to the substrate 201, the wiring board 200 on which the energy storage stacks S1 to S6 are mounted is completed. Note that the conductor members 221 to 223 and 231 to 236 shown in Figure 2 may be joined to the substrate 201 by welding or adhesive, for example, before mounting the energy storage stacks S1 to S6. The method of connecting each of the conductor members 221 to 223 and 231 to 236 to the electrode terminals of the energy storage cell 10 is arbitrary. Each of the conductor members 221 to 223 and 231 to 236 may be connected to the electrode terminals of the energy storage cell 10 via a conductive adhesive, or they may be welded to the electrode terminals of the energy storage cell 10.

[0055] Figure 6 is a diagram illustrating the details of the configuration of each of the conductor members 211 to 216. Figure 6 shows, as representative of the energy storage stacks S1 to S6, an energy storage cell 10 included in energy storage stack S1 (hereinafter also referred to as "energy storage cell C1") and an energy storage cell 10 included in energy storage stack S2 (hereinafter also referred to as "energy storage cell C2"). In Figure 6, of the two conductor members 212 provided in energy storage cell C2, the conductor member 212 on the -Y side is labeled as "conductor member 212A", and the conductor member 212 on the +Y side is labeled as "conductor member 212B".

[0056] As shown in Figure 6, the -Z ends of the conductor members 211A, 211B, 212A, and 212B are positioned in recesses R1A, R1B, R2A, and R2B formed in the substrate 201, respectively (see Figure 3). Each of the conductor members 211A, 211B, 212A, and 212B may be fixed to the substrate 201 with an adhesive (e.g., silicone adhesive). However, the substrate 201 and each conductor member may be fastened together. Recesses (countersunk holes) for accommodating bolt heads and / or washers may be formed on the back surface (-Z side) of the substrate 201.

[0057] As shown in the enlarged section of Figure 6, the conductor member 211A has a first portion P11, a second portion P12, a third portion P13, a fourth portion P14, and a fifth portion P15. The first portion P11, the second portion P12, and the fourth portion P14 are provided on the surface (-Z side) of the electrode terminal 11, the insulating member 11A, and the insulating member 11B, respectively. The third portion P13 is located between the electrode terminal 11 and the insulating member 11A. The fifth portion P15 is located between the electrode terminal 11 and the insulating member 11B. Furthermore, the conductor member 211A has a first bend P21 connecting the first portion P11 and the third portion P13, a second bend P22 connecting the second portion P12 and the third portion P13, a third bend P23 connecting the first portion P11 and the fifth portion P15, and a fourth bend P24 connecting the fourth portion P14 and the fifth portion P15. Through the first to third steps described above (see Figure 4), the conductor member 211A undergoes plastic deformation so that the first to fifth portions P11 to P15 and the first to fourth bends P21 to P24 are formed. With this configuration, it becomes possible to easily connect the energy storage cell and the conductor member and maintain these connections.

[0058] The first part P11, the second part P12, and the fourth part P14 are housed in a recess R1A formed in the substrate 201. Each of the insulating members 11A and 11B is in contact with the substrate 201 (see Figure 3). This allows for a thinner energy storage device. The electrode terminal 11 is sandwiched between the third part P13 and the fifth part P15. This creates a stable electrical connection between the electrode terminal 11 and the conductor member 211A. In addition, a first recess P31 is formed between the first bent part P21 and the second bent part P22. A second recess P32 is formed between the third bent part P23 and the fourth bent part P24. This makes it easier to apply force in the Y direction (specifically, inward force) by the cams 511 and 512 in the third step described above (see Figure 4). Furthermore, in the configuration in which the conductive member 211A is fixed to the substrate 201 with adhesive, the adhesive may penetrate into the first recess P31 and the second recess P32, respectively. In this embodiment, each of the conductive members 211 to 216 has the configuration shown in the partially enlarged view in Figure 6.

[0059] The shape of the electrode terminals of the energy storage cell is not limited to the rectangular plate shape shown in Figure 3. For example, a donut-shaped insulating member (first insulating member) may be provided so as to surround a circular plate-shaped (cylindrical) electrode terminal. Furthermore, the conductive member provided on the circular plate-shaped electrode terminal and the donut-shaped insulating member may have a first portion provided on the surface of the electrode terminal, a second portion provided on the surface of the insulating member, and a cylindrical third portion located between the electrode terminal and the insulating member.

[0060] The various features of the energy storage device described above (each feature described in the embodiments and modifications) may be applied in any combination. Also, some components may be omitted as needed. For example, in the configuration of the energy storage cell 10 shown in Figure 3, at least one of the insulating members 11B and 12B may be omitted. The application of the energy storage device is arbitrary. The energy storage device may be used in vehicles other than automobiles (railway vehicles, ships, airplanes, etc.), mobile machinery (agricultural machinery, construction machinery, etc.), unmanned mobile vehicles (autonomous transport vehicles, drones, etc.), robots, or buildings.

[0061] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the description of the embodiments above, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of Symbols]

[0062] 10 Energy storage cell, 11,12 Electrode terminals, 13 Valve, 100 Lower case, 110 Upper cover, 120 Shear panel, 200 Wiring board, 201 Circuit board, 211~216 Conductor components, B Energy storage device.

Claims

1. An energy storage device comprising an energy storage cell and a conductive member, The energy storage cell has electrode terminals and a first insulating member on the same surface. The aforementioned conductive member is A first portion provided on the surface of the electrode terminal, A second portion provided on the surface of the first insulating member, A third portion located between the electrode terminal and the first insulating member, A power storage device having the following features.

2. The energy storage cell further has a second insulating member on the surface on which the electrode terminals and the first insulating member are arranged. The aforementioned conductive member is A fourth portion provided on the surface of the second insulating member, A fifth portion located between the electrode terminal and the second insulating member, It further possesses, The energy storage device according to claim 1, wherein the electrode terminals are sandwiched between the third portion and the fifth portion.

3. The aforementioned conductive member is A first bent portion connecting the first portion and the third portion, A second bent portion connecting the second portion and the third portion, A third bent portion connecting the first portion and the fifth portion, A fourth bent portion connecting the fourth portion and the fifth portion, It further possesses, A first recess is formed between the first bent portion and the second bent portion. The energy storage device according to claim 2, wherein a second recess is formed between the third bent portion and the fourth bent portion.

4. The conductor member is plastically deformed so that the first to fifth portions and the first to fourth bent portions are formed. The first insulating member has a first inclined surface that faces the first side surface of the electrode terminal and approaches the first side surface as it approaches the base end of the electrode terminal. The energy storage device according to claim 3, wherein the second insulating member has a second inclined surface that faces the second side surface of the electrode terminal and approaches the second side surface as it approaches the base end of the electrode terminal.

5. The aforementioned energy storage device further comprises an upper cover, a lower case, a share panel, and a wiring board. The energy storage cell and the wiring board are housed between the lower case and the upper cover. The wiring board has a wiring pattern formed by a plurality of conductor members, including the conductor member. The energy storage cell further has an exhaust valve on the surface on which the electrode terminals and the first insulating member are arranged, An exhaust passage is formed between the lower case and the shear panel. The energy storage device according to any one of claims 1 to 4, wherein the first insulating member is located between the electrode terminal and the exhaust valve.

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