Power storage device
The power storage device incorporates a protective member to block exhaust gas from electrode terminals, improving heat resistance and electrical insulation, thus preventing corrosion and maintaining device integrity.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- TOYOTA JIDOSHA KK
- Filing Date
- 2025-09-30
- Publication Date
- 2026-05-21
AI Technical Summary
The exhaust gas from power storage cells in existing devices can potentially contact and corrode the electrode terminals, leading to deterioration of electrical characteristics.
A power storage device design that includes a protection member, such as a cylindrical shape surrounding the exhaust valve, with materials like mica and thermosetting resin, to block exhaust gas from reaching the electrode terminals, and a configuration that directs exhaust downward.
The protection member effectively prevents exhaust gas from contacting the electrode terminals, enhancing heat resistance and electrical insulation, thereby protecting the terminals from corrosion and maintaining device performance.
Smart Images

Figure JP2025034647_21052026_PF_FP_ABST
Abstract
Description
Power storage device
[0010]
[0001] The present disclosure relates to a power storage device.
[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.
[0003] Chinese Patent Application Publication No. 116686151
[0004] In the power storage device described in Patent Document 1 above, the exhaust gas discharged from the power storage cell is likely to touch the electrode terminal. If the exhaust gas discharged from the power storage cell touches the electrode terminal, there is a risk that the electrical characteristics of the electrode terminal will deteriorate or the electrode terminal will corrode.
[0005] The present disclosure has been made to solve the above problems, and its object is to suppress the exhaust gas discharged from the power storage cell from touching the electrode terminal.
[0006] According to the present disclosure, the following power storage device is provided.
[0007] (Item 1) The power storage device includes a power storage cell having an electrode terminal and an exhaust valve on the same plane, and a protection member at least partially existing between the electrode terminal and the exhaust valve.
[0008] In the above power storage device, since a protection member exists between the electrode terminal and the exhaust valve, the exhaust gas discharged from the exhaust valve of the power storage cell is less likely to touch the electrode terminal. The protection member acts to protect the electrode terminal from the exhaust.
[0009] (Item 2) In the power storage device according to Item 1, the protection member is formed in a cylindrical shape surrounding the exhaust valve.
[0010] 0] According to the above configuration, the exhaust gas discharged from the exhaust valve is likely to be blocked by the protection member.
[0011] (Item 3) In the power storage device according to Item 2, a plate material is provided inside the cylinder of the protection member. The plate material contains mica.
[0012] According to the above configuration, the heat resistance of the portion facing the exhaust valve can be increased. The mica-containing plate material may be formed so that a hole is created when the exhaust valve is opened.
[0013] (Article 4) In the energy storage device described in any one of paragraphs 1 to 3, the electrode terminals and exhaust valve are arranged to face downward in the vertical direction.
[0014] With the above configuration, the electrode terminals are protected by a protective member, while exhaust can be directed downward by the exhaust valve.
[0015] (Article 5) The energy storage device described in any one of paragraphs 1 to 4 further comprises an upper cover, a lower case, and a wiring board. The energy storage cells and the wiring board are housed between the lower case and the upper cover. The wiring board comprises an insulating substrate and conductive members connected to the electrode terminals of the energy storage cells. A protective member is connected to the insulating substrate.
[0016] The above configuration makes it easier to provide a protective member between the electrode terminals and the exhaust valve.
[0017] Furthermore, the phrase "the protective member is connected to the insulating substrate" includes not only cases where the protective member and insulating substrate are formed separately and then connected, but also cases where the protective member and insulating substrate are formed as a single unit.
[0018] (Paragraph 6) In the energy storage device described in Paragraph 5, the protective member is in contact with the case of the energy storage cell.
[0019] The protective member described above makes it easier to block the exhaust gas discharged from the exhaust valve before it reaches the electrode terminals. The protective member may also support the energy storage cell. The configuration specified in paragraph 6 may be combined with the configuration described in any one of paragraphs 1 to 4.
[0020] (Section 7) In the energy storage device described in Section 5 or 6, the energy storage device further comprises a shear panel on the outside of the lower case. The electrode terminals of the energy storage cells are connected to a conductive member in a vertically downward direction. An exhaust passage is formed between the lower case and the shear panel. The portion of the lower case facing the exhaust valve contains mica.
[0021] The above configuration makes it easier to secure space for an exhaust passage below the lower case. The energy storage cells can be mounted and exhausted using gravity. Furthermore, mica has excellent heat resistance and electrical insulation properties. Therefore, the heat resistance and electrical insulation of the part facing the exhaust valve can be improved. The part containing mica may be formed so that a hole opens when the exhaust valve is opened.
[0022] (Paragraph 8) In the energy storage device described in any one of paragraphs 1 to 7, the protective member includes a thermosetting resin.
[0023] Thermosetting resins have excellent heat resistance. The above protective member makes it easier to protect electrode terminals from high-temperature gases. The combination of the configurations described in item 7 and item 8 is particularly beneficial in improving the heat resistance around the exhaust valve.
[0024] (Section 9) In the energy storage device described in any one of paragraphs 1 to 8, the energy storage cell includes an electrolyte. The protective member includes at least one of polypropylene, polyethylene, and polyacetal.
[0025] Polypropylene, polyethylene, and polyacetal each exhibit excellent chemical resistance. The above protective material makes it easier to protect the electrode terminals from the electrolyte when the electrolyte is discharged from the exhaust valve along with the gas.
[0026] In another form, a vehicle equipped with the energy storage device described in any one of paragraphs 1 to 9 may be provided.
[0027] According to this disclosure, it becomes possible to suppress the exhaust gas emitted from the energy storage cell from coming into contact with the electrode terminals.
[0028] This figure shows a vehicle equipped with a power storage device according to an embodiment of the present disclosure. This figure shows a schematic configuration of a power storage device according to an embodiment of the present disclosure. This is a top view of the inside of the lower case of the power storage device according to this embodiment. This figure shows the empty lower case of the power storage device according to this embodiment. This figure shows an example of the configuration of a power storage cell according to this embodiment. This is a bottom view of each power storage cell in the lower case shown in Figure 3. This figure shows an example of the configuration of the wiring board in the lower case shown in Figure 3. This figure is for explaining the surrounding structure of the opening shown in Figure 7. This is an end view of the power storage device along the IX-IX line in Figure 3. This is an end view of the power storage device along the X-X line in Figure 3. This is an end view of the power storage device along the XI-XI line in Figure 3. This is an end view of the power storage device along the XII-XII line in Figure 3. This figure shows an enlarged view of a part of Figure 12. This figure shows a first modified example of the configuration shown in Figure 12. This figure shows a second modified example of the configuration shown in Figure 12. This figure shows a third modified example of the configuration shown in Figure 12. This figure shows a fourth modified example of the configuration shown in Figure 12. This figure is for explaining a protective member according to a fifth modified example. This figure is for explaining a protective member according to a sixth modified example. This figure shows a modified example of the configuration shown in Figure 9. This is a diagram illustrating the protective member relating to the seventh modified example.
[0029] 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.
[0030] Figure 1 shows a vehicle equipped with the energy storage device according to this embodiment. In Figure 1, the -X side corresponds to the front side of vehicle 1, and the +X side corresponds to the rear side of vehicle 1. Also, the -Z side corresponds to the downward (downward in the vertical direction), and the +Z side corresponds to the upward (upward in the vertical direction).
[0031] Referring to Figure 1, Vehicle 1 is equipped with a power storage device B. Power storage device B may function as a power storage device for driving, generally referred to as a "battery pack". Vehicle 1 is configured to be able to run using the power output from power storage device B. Vehicle 1 may be equipped with a motor that rotates the drive wheels of Vehicle 1 using the power supplied from power storage device B. Vehicle 1 is, for example, an electric vehicle (BEV) without an internal combustion engine. However, it is not limited to this, and Vehicle 1 may be a HEV (hybrid electric vehicle) or PHEV (plug-in hybrid electric vehicle) equipped with an internal combustion engine, or another electric vehicle (xEV).
[0032] The energy storage device B is installed, for example, under the floor of the vehicle 1. The energy storage device B may also be connected to the body of the vehicle 1. The energy storage device B has brackets 111 and 112 at the -X end and brackets 121 and 122 at the +X end (see Figure 3, described later). Although not shown in Figure 1, the energy storage device B also has brackets at both ends in the Y direction (for example, brackets 131 and 132 shown in Figure 3, described later). The energy storage device B is connected to the body of the vehicle 1 (for example, the floor panel) by fastening these brackets to, for example, the floor member of the vehicle 1. At least a part of the housing of the energy storage device B may function as a frame member of the vehicle 1. However, the configuration is not limited to the above, and the energy storage device B may also be installed on the floor of the vehicle 1.
[0033] Figure 2 shows a schematic configuration of the energy storage device B. Referring to Figure 2, the energy storage device B 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 +Z) 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, coolers, and junction boxes (hereinafter referred to as "J / B"), etc. (see Figure 3). The upper cover 110 and the shear panel 120 are each fixed to the lower case 100. 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 -Z) and suppresses impacts to the lower case 100 due to road surface interference. Furthermore, an exhaust passage is formed between the lower case 100 and the share panel 120. The upper cover 110 and the share panel 120 correspond to the +Z side and -Z side ends of the energy storage device B, respectively. The housing of the energy storage device B basically seals the space inside the housing (internal space). However, when a valve provided in the housing is opened, the internal space communicates with the external space through that valve.
[0034] Figure 3 is a view of the inside of the lower case 100 from the +Z side with the upper cover 110 removed. Referring to Figure 3, the energy storage stacks S1 to S6, the cooling device 20, the battery circuit unit 30, and the wiring board 200 are housed between the lower case 100 and the upper cover 110. Each of the energy storage stacks S1 to S6 contains N energy storage cells 10 arranged in the X direction. 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 greater than 50. N (the number of energy storage cells contained in one energy storage stack) can be set arbitrarily. Details of the configuration of each energy storage cell will be described later. The wiring board 200 has wiring patterns for the energy storage stacks S1 to S6. The battery circuit unit 30 includes circuits that are electrically connected to the energy storage stacks S1 to S6. The battery circuit unit 30 may be a single unit or may include multiple units.
[0035] The cooling device 20 includes ports 20A and 20B, pipes 21A and 21B extending in the Y direction, pipes 22A and 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 the order of port 20A, pipe 21A, pipe 22A, cooling pipe 23, pipe 22B, pipe 21B, and port 20B from the upstream side. Pipes 22A and 22B are connected via a plurality of coolers 22C (cooling plates) arranged in the X direction. Coolers 22C are placed between adjacent energy storage cells in the energy storage stacks S1 to S6. These adjacent energy storage cells are cooled by a refrigerant flowing through a channel formed inside the cooler 22C. The cooler 22C has a channel that communicates with each of the pipes 22A and 22B. The cooling pipe 23 is configured to cool the battery circuit unit 30.
[0036] Figure 4 shows the lower case 100 in an empty state (nothing is stored inside).
[0037] Referring to Figure 4, the lower case 100 has a bottom wall 101 (bottom) and a peripheral wall 102 (periphery). The bottom wall 101 includes regions R1 to R5. 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. Side walls W21 to W23 are located on the +X side of side walls W3 and W4 which extend in the X direction, with side wall W22 being the furthest to the +X side. Brackets 121 and 122 (Figure 1) 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, respectively, via side walls W21 and W23. Furthermore, the opposite ends (-X side) of side walls W3 and W4 are connected to each other via side wall W1, which extends in the Y direction. Brackets 131 and 132 are provided on side walls W3 and W4, respectively. Brackets 111 and 112 (Figure 1) are provided on side wall W1. Each of side walls W1 to W4 rises from the periphery of the bottom wall 101 toward the +Z side. The internal space of the lower case 100 is surrounded by side walls W1 to W4.
[0038] The bottom wall 101 is provided with partition walls 103 and 104 extending in the Y direction. Each of the partition walls 103 and 104 may be fastened to the bottom wall 101. Partition wall 104 is located on the +X side of partition wall 103. Each of the partition walls 103 and 104 stands upright on the +Z side from the bottom wall 101. Region R5 is a rectangular area located in the center of the lower case 100 and is partitioned by partition walls 103 and 104. Region R5 is the area where the wiring board 200 and the energy storage stacks S1 to S6 (Figure 3) are arranged. Region R5 is located between partition walls 103 and 104, more specifically, inside partition wall 103 and inside partition wall 104. Each of the partition walls 103 and 104 may be a cross frame.
[0039] In region R5, openings h1 are formed at the positions where each energy storage cell is arranged. 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 5), which will be described later. Multiple openings h1 are arranged in the X direction to form a row of openings h1. The bottom wall 101 has rows of openings h1 corresponding to the number of energy storage stacks (for example, six). 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.
[0040] In this embodiment, cover members 141 to 146 are provided in the region R5 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. The base material 105 may have an adhesive on one side (adhesive side). The base material 105 may be an adhesive tape such as PP (polypropylene) tape. The N lid portions 105a are formed on the base material 105. In this embodiment, the lid portions 105a contain mica. Mica has excellent heat resistance and electrical insulation properties. The N lid portions 105a of the cover members 141, 142, 143, 144, 145, and 146 are each formed to cover N openings h1 located below the energy storage stacks S1, S2, S3, S4, S5, and S6. The position of the lid portion 105a is determined according to the position of the openings h1. The size of the lid portion 105a is the same as or larger than the openings h1. For example, the 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, the 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 surface) of the bottom wall 101 via the adhesive surface of the base material 105.
[0041] Regions R3 and R4 are provided on the -Y and +Y sides of region R5, respectively. Region R1 is provided on the outside of partition wall 103 (-X side). Region R2 is provided on the outside of partition wall 104 (+X side). Region R2 is the region where the battery circuit unit 30 (Figure 3) is located. Region R2 is located at the +X end of the lower case 100 and is partitioned by partition wall 104 and side wall W2.
[0042] In this embodiment, each of the bottom wall 101, the peripheral wall 102, and the partition walls 103 and 104 is formed of metal. However, these materials can be changed as appropriate. The bottom wall 101, the peripheral wall 102, and the partition walls 103 and 104 may be formed of the same material or different materials. The bottom wall 101, the peripheral wall 102, and the partition walls 103 and 104 may be formed separately and joined, or may be formed seamlessly and integrally.
[0043] Referring to FIGS. 3 and 4, the ports 20A and 20B are provided on the side wall W1. The ports 20A and 20B are located substantially at the center of the side wall W1 in the Y direction. The port 20B is located on the +Y side of the port 20A. The pipes 21A and 21B are arranged in the region R1. The pipes 22A and 22B are arranged in the regions R3 and R4, respectively. Each of the pipes 21A, 21B, 22A, and 22B is arranged to cool the peripheral portions (regions R1, R3, and R4) of the power storage device B. The cooling pipe 23 is arranged in the region R2. The plurality of coolers 22C are arranged in the region R5.
[0044] The refrigerant supplied from the port 20A to the pipe 21A flows in the pipe 21A toward the -Y side. The refrigerant flowing from the pipe 21A into the pipe 22A flows in the pipe 22A toward the +X side toward the cooling pipe 23 and also flows into the flow paths of each of the plurality of coolers 22C. The refrigerant flowing from the pipe 22A into the cooler 22C flows toward the +Y side toward the pipe 22B while cooling the power storage stacks S1 to S6. Further, the refrigerant flowing from the pipe 22A into the cooling pipe 23 flows toward the +Y side toward the pipe 22B while cooling the battery circuit unit 30. The refrigerant flowing from the cooler 22C or the cooling pipe 23 into the pipe 22B flows in the pipe 22B toward the -X side toward the pipe 21B. Thereafter, the refrigerant flows in the pipe 21B toward the -Y side and flows out from the port 20B. <000As described above, the cooling device 20 is configured to cool the energy storage device B when it is in a high-temperature state. However, when the temperature of the energy storage device B is low due to the influence of weather or location (e.g., a cold region), the refrigerant may raise the temperature of the energy storage device B. The refrigerant may be circulated by a pump (not shown) connected to ports 20A and 20B. The vehicle 1 (Figure 1) may be equipped with a device for regulating the temperature of the refrigerant. Examples of devices for regulating the temperature of the refrigerant include a heat exchanger, chiller, and heater. The refrigerant may be a liquid (e.g., water, oil, or antifreeze) or a gas (e.g., carbon dioxide).
[0046] In this embodiment, the wiring board 200 is placed on the +Z side of the bottom wall 101, and the energy storage stacks S1 to S6 are further placed on the +Z side of the wiring board 200.
[0047] Figure 5 shows an example of the configuration of a storage cell that constitutes each of the energy storage stacks S1 to S6. Referring to Figure 5, the 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. The number of windings may be, for example, two. The windings have a structure in which 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 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 storage cell 10. The case 10a houses an electrolyte together with the electrode body 10b. The electrolyte includes, for example, an organic solvent and a lithium salt. Examples of lithium-ion batteries include LFP batteries using lithium iron phosphate as the positive electrode active material, or ternary batteries using NMC (nickel-manganese-cobalt) as the positive electrode active material. The type of secondary battery is not limited to those mentioned above; for example, an all-solid-state secondary battery may also be used. A laminated structure may be used instead of a wound structure. The laminated structure may be, for example, a laminate in which a positive electrode sheet and a negative electrode sheet are laminated with a separator in between.
[0048] The storage battery cell 10 has the electrode terminals 11, 12 and the valve 13 on the same plane. Specifically, the electrode terminals 11, 12 and the valve 13 are provided on the surface F10 of the case 10a. The surface F10 corresponds to one end face in the height direction of the storage battery cell 10. The valve 13 functions as an exhaust valve. The case 10a is basically maintained in a sealed state. However, when the pressure inside the case 10a exceeds the first reference value, the valve 13 opens to reduce the pressure inside the case 10a. Also, the electrode terminal 11 and the electrode terminal 12 are electrically connected to the positive electrode sheet and the negative electrode sheet of the electrode body 10b, respectively. The electrode terminal 11 and the electrode terminal 12 function as a positive electrode terminal and a negative electrode terminal, respectively. In the case 10a, for example, the peripheral portions of the electrode terminals 11 and 12 indicated by the broken line in FIG. 5 may be formed of an insulating material, and the other portions may be formed of metal. However, it is not limited to this, and the material of the case 10a is arbitrary.
[0049] In this embodiment, each of the storage battery stacks S1 to S6 shown in FIG. 3 is composed of a plurality of storage battery cells 10 arranged in the X direction. Each storage battery cell included in the storage battery stacks S1 to S6 has the same configuration (see FIG. 5). By forming the storage battery stacks S1 to S6 using the common storage battery cell 10, the manufacture of the storage battery device B becomes easy and the manufacturing cost can be reduced. However, it is not limited to this, and each storage battery stack may include a plurality of types of storage battery cells. Also, the number of storage battery stacks can be appropriately changed. The number of storage battery stacks may be one or more.
[0050] FIG. 6 is a view of the storage battery stacks S1 to S6 arranged in the lower case 100 as viewed from the -Z side. Referring to FIG. 6, in each of the storage battery stacks S1 to S6, the storage battery cell 10 is arranged in the lower case 100 such that the height direction coincides with the Z direction, the width direction coincides with the X direction, and the length direction coincides with the Y direction. However, N storage battery cells 10 are arranged such that the positional relationship between the electrode terminal 11 (positive electrode terminal) and the electrode terminal 12 (negative electrode terminal) is reversed every two. In each storage battery stack, in the X direction, two storage battery cells 10 with the electrode terminal 11 facing the +Y side and two storage battery cells 10 with the electrode terminal 11 facing the -Y side are alternately arranged.
[0051] Energy storage stack S1 has terminal rows T1 and T2 in the X direction. Energy storage stack S2 has terminal rows T3 and T4 in the X direction. Energy storage stack S3 has terminal rows T5 and T6 in the X direction. Energy storage stack S4 has terminal rows T7 and T8 in the X direction. Energy storage stack S5 has terminal rows T9 and T10 in the X direction. Energy storage stack S6 has terminal rows T11 and T12 in the X direction. In each terminal row, two electrode terminals 11 (positive terminals) and two electrode terminals 12 (negative terminals) are arranged alternately in the X direction. Terminal rows T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, and T12 are arranged in this order from the -Y side to the +Y side.
[0052] Energy storage stacks S1 to S6 each contain the same number of energy storage cells, and are arranged so that the positions of the energy storage cells are aligned. As a result, six energy storage cells 10 aligned in the Y direction form a row in the Y direction. Multiple rows in the Y direction are then arranged in the X direction. "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. Hereinafter, the energy storage cells 10 located at the 1st, 2nd, ..., Nth positions from the -X side end of energy storage stack S1 will be referred to as "cell 1 (1)", "cell 1 (2)", ..., and "cell 1 (N)", respectively. The energy storage cells 10 located at the 1st, 2nd, ..., Nth positions from the -X side end of energy storage stack S2 will be referred to as "cell 2 (1)", "cell 2 (2)", ..., and "cell 2 (N)", respectively. In the energy storage stack S3, the first, second, ..., Nth energy storage cells 10 from the -X end are denoted as "cell 3(1)", "cell 3(2)", ..., and "cell 3(N)", respectively. In the energy storage stack S4, the first, second, ..., Nth energy storage cells 10 from the -X end are denoted as "cell 4(1)", "cell 4(2)", ..., and "cell 4(N)", respectively. In the energy storage stack S5, the first, second, ..., Nth energy storage cells 10 from the -X end are denoted as "cell 5(1)", "cell 5(2)", ..., and "cell 5(N)", respectively. In the energy storage stack S6, the first, second, ..., Nth energy storage cells 10 from the -X end are denoted as "cell 6(1)", "cell 6(2)", ..., and "cell 6(N)", respectively.
[0053] Each energy cell included in the energy storage stack S1 to S6 shown in Figure 6 is electrically connected by the wiring pattern of the wiring board 200. The wiring board 200 has, for example, the wiring pattern shown in Figure 7. Figure 7 is a diagram showing an example of the configuration of the wiring board 200.
[0054] Referring to Figure 7, the wiring board 200 is, for example, a panel on which a wiring pattern is formed. Specifically, the wiring board 200 comprises a rectangular insulating 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 insulating substrate 201 is formed of, for example, resin. In this embodiment, the insulating substrate 201 includes, for example, a thermosetting resin such as epoxy resin, melamine resin, or phenolic resin.
[0055] Each of the multiple conductor members 211 is connected to terminal row T1 or T2 shown in Figure 6, electrically connecting the energy storage cells included in the energy storage stack S1. Each of the multiple conductor members 212 is connected to terminal row T3 or T4 shown in Figure 6, electrically connecting the energy storage cells included in the energy storage stack S2. Each of the multiple conductor members 213 is connected to terminal row T5 or T6 shown in Figure 6, electrically connecting the energy storage cells included in the energy storage stack S3. Each of the multiple conductor members 214 is connected to terminal row T7 or T8 shown in Figure 6, electrically connecting the energy storage cells included in the energy storage stack S4. Each of the multiple conductor members 215 is connected to terminal row T9 or T10 shown in Figure 6, electrically connecting the energy storage cells included in the energy storage stack S5. Each of the multiple conductor members 216 is connected to terminal row T11 or T12 shown in Figure 6, electrically connecting the energy storage cells included in the energy storage stack S6.
[0056] 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 (see Figure 3).
[0057] Each of the conductor members 211-216, 221-223, and 231-236 is, for example, a metal plate-shaped member. Each of the conductor members 221-223 may be a U-shaped plate-shaped member. Each conductor member may be a busbar. The material and shape of each conductor member are arbitrary.
[0058] In the example shown in Figure 7, each of the conductor members 211 to 216 connects two energy storage cells in parallel in the corresponding energy storage stack, and the resulting multiple parallel connections are connected in series. Each of the multiple parallel connections contains multiple energy storage cells connected in parallel. Conductor member 221 electrically connects the respective electrode terminals 11 of cell 1(1) and cell 1(2) to the respective electrode terminals 12 of cell 2(1) and cell 2(2). Conductor member 222 electrically connects the respective electrode terminals 11 of cell 3(1) and cell 3(2) to the respective electrode terminals 12 of cell 4(1) and cell 4(2). Conductor member 223 electrically connects the respective electrode terminals 11 of cell 5(1) and cell 5(2) to the respective electrode terminals 12 of cell 6(1) and cell 6(2). One end of conductor member 231 is connected to the respective electrode terminals 12 of cell 1 (N-1) and cell 1 (N), and the other end of conductor member 231 is connected to the battery circuit unit 30. One end of conductor member 232 is connected to the respective electrode terminals 11 of cell 2 (N-1) and cell 2 (N), and the other end of conductor member 232 is connected to the battery circuit unit 30. One end of conductor member 233 is connected to the respective electrode terminals 12 of cell 3 (N-1) and cell 3 (N), and the other end of conductor member 233 is connected to the battery circuit unit 30. One end of conductor member 234 is connected to the respective electrode terminals 11 of cell 4 (N-1) and cell 4 (N), and the other end of conductor member 234 is connected to the battery circuit unit 30. One end of conductor member 235 is connected to the respective electrode terminals 12 of cell 5 (N-1) and cell 5 (N), and the other end of conductor member 235 is connected to the battery circuit unit 30. One end of the conductor member 236 is connected to the respective electrode terminals 11 of cell 6(N-1) and cell 6(N), and the other end of the conductor member 236 is connected to the battery circuit unit 30. Furthermore, the battery circuit unit 30 shown in Figure 3 electrically connects cell 2(N) and cell 3(N), and also electrically connects cell 4(N) and cell 5(N). As a result, the energy storage stacks S1 to S6 are electrically connected. In the pattern shown in Figure 7, multiple parallel connections are connected in series.
[0059] The configuration of multiple energy storage cells is not limited to the configurations shown in Figures 6 and 7, and can be changed as appropriate. For example, the number of energy storage cells connected in parallel may be three or more, rather than two. Alternatively, all energy storage cells may be connected in series without forming a parallel connection.
[0060] In this embodiment, the wiring pattern of the wiring board 200 is formed by the conductor members 211 to 216. The conductor members 211 to 216 are fixed to recesses formed on the surface (+Z side) of the insulating substrate 201. Parts of the conductor members 211 to 216 are embedded in the insulating substrate 201. However, it is not essential that recesses (steps) for the conductor members 211 to 216 be formed on the surface of the insulating substrate 201. The conductor members 211 to 216 may be bonded to a flat surface of the insulating substrate 201.
[0061] As shown in Figure 7, the insulating substrate 201 has 6 × N openings h2 formed therein. These openings h2 are located between the electrode terminals of each energy storage cell included in the energy storage stack S1 to S6, more specifically below the valve 13 (on the -Z side). Each opening h2 faces the valve 13 of the energy storage cell 10 in the Z direction. The openings h2 are, for example, elongated holes penetrating the insulating substrate 201. In this embodiment, the openings h2 have larger dimensions in the X-Y plane than the openings h1 shown in Figure 4. Each of the multiple openings h1 formed in the lower case 100 is located inside one of the openings h2 in the X-Y plane. Each opening h2 is connected to the opening h1 via the lid portion 105a (see Figures 9 and 12 described later). The openings h2 are formed, for example, by punching.
[0062] A protrusion is formed on the edge of each opening h2. Figure 8 is a diagram illustrating the surrounding structure of the opening h2. Figure 8 shows an enlarged view (plan view) of the opening h2 shown in Figure 7, and an end view of the insulating substrate 201 along line VIII-VIII in the enlarged view. As shown in Figure 8, a protrusion M1 projecting to the +Z side is formed on the edge of the opening h2. The protrusion M1 is connected to the insulating substrate 201. In this embodiment, the protrusion M1 and the insulating substrate 201 are integrally formed. The protrusion M1 is made of the same material as the insulating substrate 201. The insulating substrate 201 and the protrusion M1 may each be made of, for example, resin. The protrusion M1 has an annular planar shape in the X-Y plane and surrounds the opening h2.
[0063] In this embodiment, protrusions M1 are formed on the edges of all openings h2 formed in the insulating substrate 201. However, the embodiment is not limited to this, and protrusions M1 may be provided only on predetermined openings h2. The predetermined openings h2 may be, for example, parts from which high-temperature exhaust gas is easily discharged.
[0064] In the manufacturing of the energy storage device B, for example, after installing the wiring board 200 inside the lower case 100, the energy storage stacks S1 to S6 shown in Figure 6 are rotated 180° around the X-axis as the axis of rotation, and installed on the wiring board 200 with the surface F10 of each energy storage cell facing downward in the vertical direction. Then, the energy storage stacks S1 to S6 and the wiring board 200 are connected. Furthermore, the battery circuit unit 30 is connected to the wiring board 200, and the cooling device 20 is installed inside the lower case 100. As a result, the inside of the lower case 100 is in the state shown in Figure 3. Of the cooling device 20, the cooler 22C may be installed inside the lower case 100 together with the energy storage stacks S1 to S6. The energy storage stacks S1 to S6 may be mounted on the wiring board 200 while being constrained by a pair of termination members 40a (see Figures 9 to 11), which will be described later. Afterward, the remaining portion of the cooling device 20 may be placed inside the lower case 100, and each of the pipes 22A and 22B may be connected to the cooler 22C. The wiring board 200 and the battery circuit unit 30 may each be fixed to the lower case 100 with an adhesive (for example, silicone adhesive).
[0065] The wiring board 200 is electrically connected to the battery circuit unit 30, for example, as shown in the lower part of Figure 3. 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 stack S1 to S6 (all energy storage cells). The total negative terminal 32 is located at the negative terminal end of the entire energy storage stack S1 to S6 (all energy storage cells). 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 the J / B 33. Conductor member 231 is connected to the total negative terminal 32. The wire L4 electrically connects the total negative terminal 32 to J / B33. J / B33 houses various electrical devices. J / B33 may include at least one of relays, fuses, resistors, current sensors, and connectors. An example of a connector is 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). Various sensors and signal lines may further be housed in area R5 (Figure 4) of the lower case 100. Various sensors may include, for example, temperature sensors and voltage sensors. Voltage sensors may be provided for each parallel connection or for each energy storage cell. Signal lines may transmit the detected values of each sensor to at least one of the BMS and the ECU. Signal lines may be formed by an FPC (Flexible Printed Circuit Board).
[0066] Figures 9, 10, 11, and 12 are end views of the energy storage device B along the IX-IX, X-X, XI-XI, and XII-XII lines in Figure 3, respectively.
[0067] Referring to Figures 9 to 12, an upper cover 110 is joined to the upper surface (+Z side) of each of the side walls W1 to W4, for example, via adhesive 110b, and further fastened with bolts 110a. A shear panel 120 is joined to the lower surface (-Z side) of each of the side walls W1 to W4, for example, via adhesive 120b. 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. Exhaust passages P2 and P3 are formed inside the side walls W2 and W3, respectively. Although not shown, an exhaust passage is also formed inside the side wall W4 in a manner similar to the exhaust passage P3 of the side wall W3. These exhaust passages are in communication with each other. The adhesives 110b and 120b may be adhesives with a higher thermal conductivity than air (for example, silicone adhesive).
[0068] As shown in Figure 9, an exhaust port 151a connected to the discharge valve 151 (Figure 3) is formed in the side wall W2. The exhaust port 151a penetrates the side wall W2. Although not shown, an exhaust port connected to the discharge valve 152 (Figure 3) is also formed in the side wall W2. These exhaust ports communicate with the exhaust passage P2.
[0069] As shown in Figure 9, when the internal pressure of the energy storage cell 10 exceeds a first reference value, the valve 13 opens. Then, the pressure and heat of the gas discharged from inside the energy storage cell 10 through the valve 13 create a hole in the lid 105a facing the 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 3 opens when the pressure in the exhaust passage P2 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 105a provided on the lower case 100 (Figure 4) is set to a thickness such that a hole is created when the opposing valve 13 opens. For example, a hole may be made in the cover portion 105a when the valve 13, which is involved in ignition, is opened.
[0070] 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 lid portions 105a in the X-Y plane. The mica layer 120a may be provided over the entire area R5 shown in Figure 4. The mica layer 120a protects the shear panel 120 from substances (gas, electrolyte, debris, etc.) released from the energy storage cell 10 through the lid portions 105a.
[0071] As shown in Figures 9 and 10, a space V2 exists above the battery circuit unit 30 within the lower case 100. Although not shown, the cooling pipe 23 shown in Figure 3 is located in space V2. As shown in Figure 11, a space V1 exists between the partition wall 103 and the side wall W1 within the lower case 100. Although not shown, the pipe 21A shown in Figure 3 is located in space V1. As shown in Figure 12, a space V3 exists between the energy storage cell 10 located at the -Y end of the lower case 100 and the side wall W3. Although not shown, the pipe 22A shown in Figure 3 is located in space V3. Spaces V1, V2, and V3 are located in regions R1, R2, and R3 (Figure 4) in the X-Y plane, respectively.
[0072] In each energy storage stack, an intermediate member 40 is provided between two adjacent energy storage cells 10 in the X direction. A terminal member 40a is provided on the outside of the energy storage cell 10 located at the end of each energy storage stack in the X direction.
[0073] As shown in Figure 9, the intermediate member 40 is located, for example, between cell 3(N-1) and cell 3(N). The intermediate member 40 includes a cooler 22C (Figure 3), two insulating pads 41, and two shock absorbers 42 (only one is shown). Each of the two insulating pads 41 may be a resin film. In the intermediate member 40 shown in Figure 9, one insulating pad 41 is located between the cooler 22C and cell 3(N-1), and the other insulating pad 41 is located between the cooler 22C and cell 3(N). The shock absorbers 42 are located at both ends of the intermediate member 40 in the Z direction and suppress the transmission of shock to the cooler 22C. Figure 9 shows only the +Z end of the intermediate member 40, but the -Z end has a similar structure.
[0074] As shown in Figure 9, the terminal member 40a is located, for example, on the outside (+X side) of cell 3(N). The terminal member 40a includes a cooler 22C (Figure 3), an insulating pad 41, an insulating pad 41a, and two shock absorbers 42a (only one is shown). The terminal member 40a basically has the same structure as the intermediate member 40. However, in the terminal member 40a, one of the two insulating pads 41 in the intermediate member 40 is replaced with an insulating pad 41a that is formed thicker than the insulating pad 41. This makes it more difficult for shocks to be transmitted from the outside to the energy storage section (energy storage stack S1 to S6). The shock absorbers 42a are located at both ends of the terminal member 40a in the Z direction and suppress the transmission of shocks to the cooler 22C. Figure 9 shows only the +Z side end of the terminal member 40a, but the -Z side end has a similar structure.
[0075] As shown in Figure 10, the partition wall 104 has an opening 104a through which the conductor member 232 passes. The conductor member 232 is connected to the battery circuit unit 30 through the opening 104a. Although not shown, the partition wall 104 also has openings through which each of the conductor members 231, 233, 234, 235, and 236 shown in Figure 3 passes.
[0076] As shown in Figure 12, in the energy storage device B, a protrusion M1 is provided between each of the electrode terminals 11 and 12 and the valve 13 (exhaust valve). The protrusion M1 functions as a protective member. Specifically, the electrode terminals 11 and 12 and the valve 13 of the energy storage cell 10 are arranged facing downward (-Z side) in the vertical direction (Z direction). The presence of the protrusion M1 between each of the electrode terminals 11 and 12 and the valve 13 makes it difficult for the exhaust gas discharged from the valve 13 to come into contact with each of the electrode terminals 11 and 12. The protrusion M1 is formed to suppress the gas discharged from the valve 13 from heading towards each of the electrode terminals 11 and 12. The protrusion M1 acts to protect each of the electrode terminals 11 and 12 from exhaust gas. With the above configuration, the electrode terminals 11 and 12 are protected by the protrusion M1, while downward exhaust by the valve 13 is possible.
[0077] As shown in Figures 9 and 12, in the energy storage device B, an exhaust passage P1 (gas flow path) is formed between the bottom wall 101 of the lower case 100 and the shear panel 120. The portion of the lower case 100 facing the valve 13 (lid portion 105a) contains mica. The mica improves the heat resistance and electrical insulation of the portion facing the valve 13. In addition, the inclusion of thermosetting resin in the protrusion M1 makes it easier to protect the electrode terminals 11 and 12 from high-temperature gas.
[0078] Figure 13 is an enlarged view of a portion of Figure 12. Referring to Figure 13, the conductor member 211 is positioned in a recess R10 formed on the +Z side of the insulating substrate 201. The recess R10 is formed to a depth of D4. Although not shown in Figure 13, in this embodiment, other conductor members provided on the insulating substrate 201 are also positioned in recesses of depth D4. Furthermore, all conductor members (including the conductor member 211) provided on the insulating substrate 201 are formed to the same thickness D3. The depth D4 is smaller than the thickness D3. Each of the electrode terminals 11 and 12 of the energy storage cell 10 is connected to one of the conductor members in a vertically downward direction. In this embodiment, the electrode terminals 11 and 12 of all energy storage cells 10 housed in the lower case 100 have the same thickness D2.
[0079] The height D1 of the protrusion M1 corresponds to the amount of protrusion from the surface F11 of the insulating substrate 201 to the tip surface of the protrusion M1. Surface F11 corresponds to the flat surface on the +Z side of the insulating substrate 201 where neither the protrusion M1 nor the recess R10 is formed. In this embodiment, the height D1 of the protrusion M1 is set to satisfy the formula "height D1 = thickness D2 + thickness D3 - depth D4". The formation of the recess R10 makes it easier to shorten the protrusion M1. The larger the depth D4, the easier it is to reduce the height D1. The protrusion M1 is in contact with the case 10a of the energy storage cell 10. More specifically, the tip surface of the protrusion M1 is in contact with the surface F10 of the energy storage cell 10. The energy storage cell 10 is supported by the protrusion M1. In addition, the presence of an insulating protrusion M1 between two adjacent electrode terminals in the Y direction, specifically the positive electrode terminal and the negative electrode terminal, enhances the electrical insulation between the electrode terminals. However, the dimensions of each component of the energy storage device B can be changed as appropriate.
[0080] The electrode terminals of the energy storage cell 10 and the conductor members of the wiring board 200 may be joined by crimping, heat pressing, or welding (for example, laser welding). Alternatively, these electrode terminals and conductor members may be fastened together. A recess (countersink) for accommodating bolt heads and / or washers may be formed on the back surface (-Z side) of the insulating substrate 201.
[0081] In the above embodiment, the protective member (protrusion M1) is integrally formed with the insulating substrate (insulating substrate 201) of the wiring board. However, the embodiment is not limited to this, and the protective member and insulating substrate may be formed separately and then connected.
[0082] Figure 14 shows a first modified example of the configuration shown in Figure 12. Referring to Figure 14, in this modified example, a protective member M2 and an insulating substrate 201A are used instead of the protrusion M1 and the insulating substrate 201 (Figure 12). The insulating substrate 201A functions similarly to the insulating substrate 201 as an insulating substrate for a wiring board having, for example, the wiring pattern shown in Figure 7. However, the insulating substrate 201A is provided with a protective member M2 instead of the protrusion M1. The protective member M2 may be formed from a different material than the insulating substrate 201A. The protective member M2 may be formed from, for example, metal. However, the material of the protective member M2 can be changed as appropriate. The protective member M2 may include ceramic. The protective member M2 may include at least one of polypropylene, polyethylene, and polyacetal.
[0083] The protective member M2 is positioned between each of the electrode terminals 11 and 12 and the valve 13. The protective member M2 acts to protect each of the electrode terminals 11 and 12 from exhaust. The protective member M2 is in contact with both the surface F10 of the energy storage cell 10 and the bottom wall 101 of the lower case 100. As shown in the plan view on the left side of Figure 14, the protective member M2 is formed in an annular shape, similar to the protrusion M1 (Figure 8), and is positioned on the edge of the opening h2. In the modified example shown in Figure 14, the protective member M2 is in contact with the inner wall of the opening h2 of the insulating substrate 201A. The protective member M2 is bonded to at least one of the surface F10 of the energy storage cell 10, the bottom wall 101 of the lower case 100, and the insulating substrate 201A.
[0084] Figure 15 shows a second modified example of the configuration shown in Figure 12. Referring to Figure 15, in this modified example, a protective member M3, an insulating substrate 201B, and a lower case 100B are used instead of the protrusion M1, insulating substrate 201, and lower case 100 (Figure 12). The insulating substrate 201B functions similarly to the insulating substrate 201, for example, as an insulating substrate for a wiring board having the wiring pattern shown in Figure 7. However, the insulating substrate 201B is provided with a protective member M3 instead of the protrusion M1. The protective member M3 is formed in a cylindrical shape that surrounds the valve 13. Specifically, as shown in the perspective view on the left side of Figure 15, the protective member M3 comprises a cylindrical main body M3a and a flange M3b provided at the upper part (+Z side end) of the main body M3a. The flange M3b is positioned on the upper surface (+Z side surface) of the insulating substrate 201B. An annular through-hole h1B (through-groove) corresponding to the main body portion M3a is formed in the bottom wall 101B of the lower case 100B. The main body portion M3a passes inside the opening h2 and is inserted into the through-hole h1B. The main body portion M3a penetrates the bottom wall 101B and protrudes into the exhaust passage P1. The protective member M3 is bonded to at least one of the surface F10 of the energy storage cell 10 and the insulating substrate 201B. The protective member M3 may be made of resin (for example, thermosetting resin or thermoplastic resin). The protective member M3 may include at least one of polypropylene, polyethylene, and polyacetal. However, the material of the protective member M3 can be changed as appropriate. The protective member M3 may include metal. The protective member M3 may include ceramic.
[0085] Figure 16 shows a third modified example of the configuration shown in Figure 12. Referring to Figure 16, in this modified example, a protective member M4, an insulating substrate 201C, and a lower case 100C are used instead of the protrusion M1, insulating substrate 201, and lower case 100 (Figure 12). The insulating substrate 201C functions similarly to the insulating substrate 201, for example, as an insulating substrate for a wiring board having the wiring pattern shown in Figure 7. However, the insulating substrate 201C is provided with a protective member M4 instead of the protrusion M1. The protective member M4 is formed in a cylindrical shape that surrounds the valve 13. Specifically, as shown in the perspective view on the left side of Figure 16, the protective member M4 comprises a cylindrical main body M4a, a flange M4b provided at the upper part (+Z side end) of the main body M4a, and a flange M4c provided at the lower part (-Z side end) of the main body M4a. The flange portion M4b is located on the upper surface (+Z side) of the insulating substrate 201C. The flange portion M4c is located on the lower surface (-Z side) of the bottom wall 101C of the lower case 100C, i.e., within the exhaust passage P1. An annular through hole h1C (through groove) corresponding to the main body portion M4a is formed in the bottom wall 101C. The main body portion M4a passes inside the opening h2 and is inserted into the through hole h1C. After inserting the main body portion M4a into the through hole h1C, the main body portion M4a and the flange portion M4c may be integrally formed by bending or pressing. Alternatively, after inserting the main body portion M4a into the through hole h1C, the flange portion M4c, which is formed separately from the main body portion M4a, may be joined to the main body portion M4a. The protective member M4 is bonded to at least one of the surface F10 of the energy storage cell 10, the bottom wall 101C of the lower case 100C, and the insulating substrate 201C. The protective member M4 may be formed of resin (for example, thermosetting resin or thermoplastic resin). However, the material of the protective member M4 can be changed as appropriate. In the protective member M4, the main body portion M4a, the flange portion M4b, and the flange portion M4c may be formed of the same material or of different materials.
[0086] Figure 17 shows a fourth modified example of the configuration shown in Figure 12. Referring to Figure 17, in this modified example, a protective member M5, an insulating substrate 201D, and a lower case 100D are used instead of the protrusion M1, insulating substrate 201, and lower case 100 (Figure 12). The insulating substrate 201D functions similarly to the insulating substrate 201, for example, as an insulating substrate for a wiring board having the wiring pattern shown in Figure 7. However, the insulating substrate 201D and the lower case 100D are provided with a protective member M5 instead of the protrusion M1 and cover members 141-146. In addition, the bottom wall 101D of the lower case 100D has an opening h1D formed in place of the opening h1, which has the same dimensions and shape as the opening h2 in the X-Y plane. The openings h2 and h1D are arranged to overlap in the X-Y plane.
[0087] The protective member M5 basically has the same configuration as the protective member M3 shown in Figure 15. However, as shown in the perspective view on the left side of Figure 17, the protective member M5 further comprises a plate material M5c in addition to a cylindrical main body M5a and a flange M5b provided on the upper part of the main body M5a. The plate material M5c is provided inside the cylinder of the protective member M5 to close the opening of the protective member M5. The plate material M5c has a function similar to that of the lid 105a. The plate material M5c contains mica. The plate material M5c is perforated when the opposing valve 13 is opened. The thickness of the plate material M5c is set to a thickness such that a hole is made when the opposing valve 13 is opened. The plate material M5c may be perforated, for example, when the valve 13 that causes ignition is opened. The main body M5a passes inside the openings h2 and h1D and protrudes into the exhaust passage P1. In the modified example shown in Figure 17, the plate material M5c is positioned closer to the upper surface than the lower surface of the protective member M5. The plate material M5c is located on the +Z side (towards the energy storage cell 10) of the bottom wall 101D. However, this is not the only option, and the position of the plate material M5c can be changed as appropriate. In addition, the protective member M4 shown in Figure 16 may be provided with a plate material having the same configuration as the plate material M5c.
[0088] Figure 18 is a diagram illustrating a protective member according to a fifth modified example. The insulating substrate 201E shown in Figure 18 functions as an insulating substrate for a wiring board having, for example, the wiring pattern shown in Figure 7, similar to the insulating substrate 201. In Figure 18, the wiring pattern (conductor member) is omitted. In the insulating substrate 201E, protective members M6 surrounding N openings h2 are provided for each energy storage stack. In the example shown in Figure 18, six protective members M6 are provided on the insulating substrate 201E. The protective members M6 are connected to the insulating substrate 201E and stand upright on the +Z side from the insulating substrate 201E. The protective members M6 may be formed integrally with the insulating substrate 201E or may be formed separately from the insulating substrate 201E.
[0089] Figure 19 is a diagram illustrating a protective member according to the sixth modified example. The insulating substrate 201F shown in Figure 19 functions as an insulating substrate for a wiring board having, for example, the wiring pattern shown in Figure 7, similar to the insulating substrate 201. In Figure 19, the wiring pattern (conductor member) is omitted. In the insulating substrate 201F, a pair of protective members M7A and M7B, which sandwich N openings h2, are provided for each energy storage stack. Each of the protective members M7A and M7B is formed, for example, as a long rod or plate in the X direction. The X direction corresponds to the direction in which the N openings h2 are lined up, and further, to the direction in which the energy storage cells are lined up in each energy storage stack. Each of the protective members M7A and M7B is connected to the insulating substrate 201F and stands upright on the +Z side from the insulating substrate 201F. Each of the protective members M7A and M7B may be formed integrally with the insulating substrate 201F, or may be formed separately from the insulating substrate 201F.
[0090] In both the fifth modified example shown in Figure 18 and the sixth modified example shown in Figure 19, the end face of the XII-XII line in Figure 3 is similar to the structure shown in Figure 12. On the other hand, in both the fifth modified example shown in Figure 18 and the sixth modified example shown in Figure 19, the end face of the IX-IX line in Figure 3 is the structure shown in Figure 20. Figure 20 is a diagram showing a modified version of the configuration shown in Figure 9. In both the insulating substrate 201E (Figure 18) and the insulating substrate 201F (Figure 19), no protrusion (for example, the protrusion M1 shown in Figure 9) is formed between two adjacent openings h2 in the X direction.
[0091] A multilayer protective member may be used. Figure 21 is a diagram illustrating a protective member according to the seventh modified example. As shown in Figure 21, the protective member M2 shown in Figure 14 may be changed to a two-layer structure. In the example shown in Figure 21, a protective member M8 is provided instead of protective member M2. The protective member M8 has an outer first layer M8a and an inner second layer M8b. As shown in the plan view on the left side of Figure 21, each of the first layer M8a and the second layer M8b is formed in an annular shape and is located at the edge of the opening h2. For example, the first layer M8a contains a thermosetting resin, and the second layer M8b contains at least one of polypropylene, polyethylene, and polyacetal. The second layer M8b may be formed by a surface treatment agent.
[0092] The materials of the first layer M8a and the second layer M8b can be changed as appropriate. For example, the first layer M8a may be made of metal and the second layer M8b may be made of resin. Alternatively, the first layer M8a may be made of resin and the second layer M8b may be made of metal. Furthermore, the protective member may have a multilayer structure of three or more layers, with each layer having different properties.
[0093] In the above embodiment, openings for passing the conductor members 231 to 236 are formed in the partition wall 104 (see Figure 10). However, the embodiment is not limited to this, and the partition wall 104 may be changed to a plurality of divided partition plates. The conductor members 231 to 236 may pass in the X direction between partition plates arranged in the Y direction. Alternatively, the wires (e.g., cables) connected to the wiring board 200 may be connected to the battery circuit unit 30 by passing over the partition wall 104 shown in Figure 3. An equipment cooler (including cooling piping 23) for cooling the battery circuit unit 30 may be provided below the battery circuit unit 30. It is not essential that the cell cooler (e.g., cooler 22C) for cooling the energy storage cells be placed between adjacent energy storage cells. The cell cooler may be provided above the energy storage cells. The cell cooler may be provided so as to cover the top surface of all energy storage cells. Note that the partition walls 103 and 104 shown in Figure 3 are not essential configurations. At least one of the partition walls 103 and 104 may be omitted. Also, at least one of the two end members (a pair of end members) may be omitted. Furthermore, at least one of the exhaust valves 151 and 152 may be omitted. The gas flowing through each exhaust passage may be discharged to the outside of the energy storage device B through an exhaust port (for example, exhaust port 151a). The discharged gas may be guided to a predetermined location by a duct provided outside the housing of the energy storage device B.
[0094] In the above embodiments and their respective modifications, the planar shapes of the openings and protective members can be changed as appropriate. For example, the circularly formed openings and protective members may be changed to polygonal shapes (triangular, rectangular, hexagonal, octagonal, etc.).
[0095] The various features relating to the energy storage device described in the embodiments and modifications may be applied in any combination.
[0096] The use of the energy storage device is arbitrary. The energy storage device may be used in vehicles other than automobiles (electric motorcycles, electric wheelchairs, railway vehicles, ships, airplanes, electric vertical take-off and landing aircraft (eVTOLs), amphibious aircraft, etc.), mobile machinery (agricultural machinery, construction machinery, etc.), unmanned mobile vehicles (automated guided vehicles (AGVs), mobile robots, drones, robotic cleaners, space probes, etc.), wearable robots, stationary robots (e.g., industrial robots), or buildings (houses, factories, etc.).
[0097] 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 of the claims are intended to be included.
[0098] 1 Vehicle, 10 Energy storage cell, 11, 12 Electrode terminals, 13 Valve, 100 Lower case, 101 Bottom wall, 102 Peripheral wall, 110 Upper cover, 120 Share panel, 200 Wiring board, 201 Insulating substrate, 211-216 Conductor members, B Energy storage device, M1 Protrusion, M2-M6, M7A, M7B, M8 Protective members, S1-S6 Energy storage stack.
Claims
1. An energy storage device comprising an energy storage cell having electrode terminals and an exhaust valve on the same plane, and a protective member whose portion is located between the electrode terminals and the exhaust valve.
2. The energy storage device according to claim 1, wherein the protective member is formed in a cylindrical shape surrounding the exhaust valve.
3. The energy storage device according to claim 2, wherein a plate material is provided inside the cylinder of the protective member, and the plate material contains mica.
4. The energy storage device according to any one of claims 1 to 3, wherein the electrode terminals and the exhaust valve are arranged facing downward in the vertical direction.
5. The energy storage device according to claim 1, further comprising an upper cover, a lower case, and a wiring board, wherein the energy storage cell and the wiring board are housed between the lower case and the upper cover, the wiring board comprises an insulating substrate and a conductor member connected to the electrode terminals of the energy storage cell, and the protective member is connected to the insulating substrate.
6. The energy storage device according to claim 5, wherein the protective member is in contact with the case of the energy storage cell.
7. The energy storage device according to claim 5 or 6, further comprising a shear panel on the outside of the lower case, the electrode terminals of the energy storage cell being connected to the conductor member in a vertically downward direction, an exhaust passage being formed between the lower case and the shear panel, and the portion of the lower case facing the exhaust valve comprising mica.
8. The energy storage device according to claim 7, wherein the protective member includes a thermosetting resin.
9. The energy storage device according to claim 1, wherein the energy storage cell contains an electrolyte, and the protective member contains at least one of polypropylene, polyethylene, and polyacetal.