Battery pack

Abstract

A battery pack (10) is provided with: a battery module (100); a module housing body (300) that houses the battery module (100); a gas discharge unit (400) that discharges gas discharged from the battery module (100) from the module housing body (300); and an upper heat-resistant sheet (610) and a lower heat-resistant sheet (620) disposed at least partially around a communication space (350) communicating with the battery module (100) and the gas discharge part (400) inside the module housing body (300).

Description

Technical Field

[0001] This invention relates to battery packs. Background Technology

[0002] In recent years, various battery packs have been developed. A battery pack consists of multiple battery modules and a housing that holds the battery modules. Each battery module has multiple individual cells that are electrically connected to each other via series and parallel connections.

[0003] Patent document 1 describes a battery tray for accommodating single cells. The battery tray includes a base plate, side beams, and multiple partitions. Gas generated from the single cell is discharged through air intakes located in each partition and gas passages located inside each partition and the side beams, and then through a battery pack explosion-proof valve located in the side beams.

[0004] Patent document 2 describes a battery device. The battery device includes a battery and a container for accommodating the battery. The container has: a housing portion for accommodating the battery; an inlet portion for air to flow in; and an outlet portion for gas to flow out from the inlet portion and through the housing portion.

[0005] Patent document 3 describes a battery pack. The battery pack includes a battery stack, a lower housing, and an upper housing to house the battery stack. Each cell in the battery stack has a discharge valve on its upper surface. A plate is provided on the lower surface of the upper housing. With the upper housing covering the upper surfaces of each cell, the plate and the discharge valve overlap each other.

[0006] Prior art literature

[0007] Patent documents

[0008] Patent Document 1: JP Patent No. 2022-515674

[0009] Patent Document 2: JP 2020-053223

[0010] Patent Document 3: JP 2019-197622 Summary of the Invention

[0011] The problem that the invention aims to solve

[0012] Gas discharged from the battery module is released through a gas venting section such as a pressure relief device (PRD) located within the housing. The gas discharged from the battery module is sometimes quite hot. If hot gas is discharged from the battery module, the temperature around the space inside the housing that communicates with the battery module and the gas venting section may rise due to the gas.

[0013] One example of the object of the present invention is to suppress the temperature rise of the battery pack caused by gases emitted from the battery module. Other objects of the present invention will become apparent from the description herein.

[0014] Methods for solving problems

[0015] One aspect of the present invention is as follows.

[0016] 1. A battery pack, comprising:

[0017] Battery module;

[0018] A housing that houses the battery module;

[0019] A gas exhaust section, which exhausts the gas discharged from the battery module from the housing; and

[0020] A heat-resistant body, which is at least partially disposed inside the housing around a space communicating with the battery module and the gas exhaust section.

[0021] 2. In the battery pack described in 1,

[0022] The heat-resistant material covers at least a portion of the battery module.

[0023] 3. In the battery pack described in section 2,

[0024] The battery module includes: a single battery cell with tabs; and a voltage detection device electrically connected to the tabs.

[0025] The heat-resistant body overlaps with at least one of the electrode and the voltage detection device.

[0026] 4. In the battery pack described in 2 or 3,

[0027] The battery module has a gas discharge section for discharging the gas.

[0028] The gas exhaust section is exposed from the heat-resistant body.

[0029] 5. In any of the battery packs described in 1. to 4,

[0030] The housing also houses other battery modules.

[0031] The heat-resistant material covers at least a portion of the other battery modules.

[0032] 6. In any of the battery packs described in 1. to 5.,

[0033] The heat-resistant material covers at least a portion of the container.

[0034] Invention Effects

[0035] According to the above-described manner of the present invention, it is possible to suppress the temperature rise of the battery pack caused by the gas discharged from the battery module. Attached Figure Description

[0036] Figure 1 This is a perspective view of the battery pack involved in the implementation method.

[0037] Figure 2 This is a top view of the battery pack with the wiring harness guide and upper housing removed according to the embodiment.

[0038] Figure 3 yes Figure 2 AA sectional view.

[0039] Figure 4 yes Figure 2 BB cross-sectional view.

[0040] Figure 5 This is an exploded perspective view of an example of a battery module involved in the implementation method.

[0041] Figure 6 This is a top view of the battery pack in the modified example with the wiring harness guide and upper housing removed.

[0042] Figure 7 This is a perspective view of the single-piece upper plate and the first heat-resistant sheet involved in the modified example. Detailed Implementation

[0043] Hereinafter, embodiments and variations of the present invention will be described using the accompanying drawings. In all the drawings, the same reference numerals are used to denote the same constituent elements, and descriptions may be omitted as appropriate.

[0044] Figure 1 This is a perspective view of the battery pack 10 according to the embodiment. Figure 2 This is a top view of the battery pack 10 in the embodiment with the wiring harness guide 220 and the upper housing 320 removed. Figure 3 yes Figure 2 AA sectional view. Figure 4 yes Figure 2 BB cross-sectional view. Figure 5 This is an exploded perspective view of an example of the battery module 100 according to the embodiment.

[0045] In this embodiment, the battery pack 10 is mounted in a vehicle. Specifically, the battery pack 10 is mounted between the front and rear wheels of the vehicle. Unless otherwise specified, the following description refers to the battery pack 10 being mounted in a vehicle. However, the battery pack 10 can also be used for applications other than automobiles.

[0046] In the figures, the X, Y, and Z directions are shown for illustrative purposes. The X direction represents the front-to-back direction of the battery pack 10. The Y direction is orthogonal to the X direction. The Z direction represents the left-to-right direction of the battery pack 10. The Z direction is orthogonal to both the X and Y directions. The Z direction represents the up-and-down direction of the battery pack 10. The arrows indicating the X direction, Y direction, and Z direction represent the front, left, and up directions of the battery pack 10, respectively. Figures 2-4 In the diagram, the white circle with a black dot representing the Y or Z direction indicates an arrow pointing in that direction extending from the depth of the paper towards the front. The relationship between the X, Y, and Z directions and the front-back, left-right, and up-down directions of the battery pack 10 is not limited to this example.

[0047] In this embodiment, the forward / backward, left / right, and up / down directions of the battery pack 10 are determined by the vehicle carrying the battery pack 10. The X, Y, and Z directions represent the forward / backward, left / right, and up / down directions of the vehicle, respectively. The arrows indicating the X, Y, and Z directions represent the forward, left, and up directions of the vehicle, respectively. However, the relationship between the forward / backward, left / right, and up / down directions of the battery pack 10 and the forward / backward, left / right, and up / down directions of the vehicle is not limited to this example.

[0048] From here on, the direction perpendicular to the Z direction will be referred to as the horizontal direction, as needed.

[0049] refer to Figures 1-4 Let's explain battery pack 10.

[0050] like Figures 2-4 As shown, the battery pack 10 includes: four battery modules 100, a junction box 210, a wiring harness guide 220, a module housing 300, a gas vent 400, two spacers 500, four upper heat-resistant sheets 610, and two lower heat-resistant sheets 620. The module housing 300 has a lower housing 310 and an upper housing 320. The lower housing 310 includes a lower module plate 312, a side frame 314, and a support frame 316. The lower housing 310 is sometimes also referred to as, for example, a tray or a main body. The upper housing 320 is sometimes also referred to as, for example, a cover or a lid.

[0051] like Figure 2As shown, viewed from the Z direction, the four battery modules 100 are arranged in 2 rows and 2 columns in both the X and Y directions. Hereinafter, as needed, the battery module 100 located on the left front side will be referred to as the left front battery module 100, the battery module 100 located on the right front side will be referred to as the right front battery module 100, the battery module 100 located on the left rear side will be referred to as the left rear battery module 100, and the battery module 100 located on the right rear side will be referred to as the right rear battery module 100. The number and arrangement of the battery modules 100 are not limited to [specific configuration details needed]. Figure 2 The example shown.

[0052] refer to Figure 5 To explain each battery module 100.

[0053] Each battery module 100 includes: multiple battery cells 110, multiple compression pads 120, a front voltage detection device 130, a rear voltage detection device 140, and a cell housing 150.

[0054] Multiple battery cells 110 are stacked along the Y direction. Multiple compression pads 120 and multiple battery cells 110 are alternately stacked along the Y direction. Each compression pad 120 is disposed between adjacent battery cells 110 in the Y direction and on both sides of the multiple battery cells 110 in the Y direction. Hereinafter, as needed, the multiple battery cells 110 and multiple compression pads 120 alternately stacked along the Y direction will be referred to as a stack of battery cells 110. The long side direction of each battery cell 110 is substantially parallel to the X direction. The short side direction of each battery cell 110 is substantially parallel to the Z direction. The thickness direction of each battery cell 110 is substantially parallel to the Y direction. The shape of each battery cell 110 is not limited to this example.

[0055] Each battery cell 110 includes a battery element (not shown), an outer casing 112, a positive electrode tab 114, and a negative electrode tab 116. In one example, the battery element includes a plurality of positive electrodes (not shown) and a plurality of negative electrodes (not shown) alternately stacked along the Y direction, and a separator (not shown) located between adjacent positive and negative electrodes in the Y direction. The outer casing 112 seals the battery element and an electrolyte (not shown). The positive electrode tab 114 is electrically connected to the positive electrode of the battery element. The positive electrode tab 114 extends from one side of the outer casing 112 in the X direction. The negative electrode tab 116 is electrically connected to the negative electrode of the battery element. The negative electrode tab 116 extends from the other side of the outer casing 112 in the X direction. The construction of each battery cell 110 is not limited to this example.

[0056] Each battery cell 110 can also be an all-solid-state battery. In an all-solid-state battery, a solid electrolyte layer is provided in the portion that serves as a separator. All-solid-state batteries do not contain electrolyte. Hereinafter, unless otherwise specified, each battery cell 110 will be described as a battery cell containing electrolyte.

[0057] Multiple battery cells 110 are electrically connected by a combination of series and parallel connections. Specifically, a group of cells comprising at least two adjacent and parallel-connected battery cells 110 in the Y direction is stacked and connected in series along the Y direction. At the front of the stack of battery cells 110, a tab group 118 comprising the positive tab 114 and the negative tab 116 is electrically connected to each other, for example, by connecting the positive tab 114 and the negative tab 116 to the other parallel-connected battery cells 110. The positive tab 114 and the negative tab 116 in the tab group 118 are joined together by laser welding. A tab group 118 is also similarly arranged at the rear of the stack of battery cells 110. Thus, multiple groups of cells are connected in series from one end of the stack of battery cells 110 in the Y direction to the other end of the stack of battery cells 110 in the Y direction. Hereinafter, as needed, the tab group 118 located on the front side of the stack of battery cell 110 will be referred to as the front tab group 118, and the tab group 118 located on the rear side of the stack of battery cell 110 will be referred to as the rear tab group 118.

[0058] The electrical connection of multiple battery cells 110 is not limited to the examples described above. For example, individual battery cells 110 can be connected in series to form a stack of battery cells 110. Alternatively, each group of cells may contain three or more battery cells 110 connected in parallel.

[0059] The front voltage detection device 130 detects the voltage of multiple front-side tab groups 118. The front voltage detection device 130 includes: a front protection member 131, multiple front voltage detection terminals 132, multiple front voltage detection lines 133, a front connector 134, and a front bus bar 135.

[0060] The front protective member 131 covers the front portion of the laminate of the battery cell 110. The front protective member 131 is, for example, an insulator such as resin. The front protective member 131 is defined with a plurality of front openings 131a. A plurality of front tab groups 118 are each exposed forward through a plurality of front openings 131a.

[0061] Multiple front voltage detection terminals 132 are each located in front of multiple front-side tab groups 118. Each front voltage detection terminal 132 is, for example, a conductor such as metal. The rear surface of each front voltage detection terminal 132 is joined to the front surface of each front-side tab group 118 by a joining method such as laser welding. Therefore, each front voltage detection terminal 132 and each front-side tab group 118 are electrically connected to each other. Therefore, the front voltage detection device 130 can detect the voltage of each front-side tab group 118 using each front voltage detection terminal 132. The multiple front voltage detection terminals 132 are integrally held by a front protective member 131. Therefore, by positioning the front protective member 131 in an appropriate position relative to the stack of battery cells 110, each of the multiple front voltage detection terminals 132 can be positioned appropriately relative to each of the multiple front-side tab groups 118.

[0062] One end of each front voltage detection line 133 is electrically connected to each front voltage detection terminal 132. The other end of each front voltage detection line 133 is electrically connected to the front connector 134. Therefore, the plurality of front voltage detection terminals 132 and the front connector 134 are electrically connected to each other via the plurality of front voltage detection lines 133. Each front voltage detection line 133 is arranged between one end of each front voltage detection line 133 and the other end of each front voltage detection line 133 via the front protection member 131.

[0063] The front busbar 135 is disposed at the right end of the front protective member 131. The front busbar 135 is electrically connected to the positive electrode tab 114 extending forward from the battery cell 110 of the battery cell group located at the right end of the stack of battery cells 110. The front busbar 135 functions as an external terminal for electrically connecting the battery module 100 to other external devices such as battery modules.

[0064] The rear voltage detection device 140 detects the voltage of multiple rear tab groups 118. The rear voltage detection device 140 includes: a rear protection member 141, multiple rear voltage detection terminals 142, multiple rear voltage detection lines 143, a rear connector 144, and a rear busbar 145.

[0065] The rear protective member 141 covers the rear portion of the stack of battery cells 110. The rear protective member 141 is, for example, an insulator such as resin. The rear protective member 141 is defined with a plurality of rear openings 141a. A plurality of rear-side tab groups 118 are each exposed rearward through the plurality of rear openings 141a.

[0066] Multiple rear voltage detection terminals 142 are each located behind multiple rear tab groups 118. Each rear voltage detection terminal 142 is, for example, a conductor such as metal. The front surface of each rear voltage detection terminal 142 is joined to the rear surface of each rear tab group 118 by a joining method such as laser welding. Therefore, each rear voltage detection terminal 142 and each rear tab group 118 are electrically connected to each other. Therefore, the rear voltage detection device 140 can detect the voltage of each rear tab group 118 using each rear voltage detection terminal 142. The multiple rear voltage detection terminals 142 are integrally held by a rear protective member 141. Therefore, by positioning the rear protective member 141 in an appropriate position relative to the stack of battery cells 110, each of the multiple rear voltage detection terminals 142 can be positioned appropriately relative to each of the multiple rear tab groups 118.

[0067] One end of each rear voltage detection line 143 is electrically connected to each rear voltage detection terminal 142. The other end of each rear voltage detection line 143 is electrically connected to the rear connector 144. Therefore, the plurality of rear voltage detection terminals 142 and the rear connector 144 are electrically connected to each other via the plurality of rear voltage detection lines 143. Each rear voltage detection line 143 is arranged between one end of each rear voltage detection line 143 and the other end of each rear voltage detection line 143 via a rear protection member 141.

[0068] The rear busbar 145 is disposed at the left end of the rear protection member 141. The rear busbar 145 is electrically connected to the negative electrode tab 116 extending rearward from the battery cell 110 of the battery cell group located at the left end of the stack of battery cells 110. The rear busbar 145 functions as an external terminal for electrically connecting the battery module 100 to other external devices such as battery modules.

[0069] exist Figure 5In the example shown, the positive electrode tabs 114 at the ends of the series-connected multiple cell groups extend forward from the cell group 110 located on the right side of the stack of cell groups 110, and the negative electrode tabs 116 at the ends of the series-connected multiple cell groups extend backward from the cell group 110 located on the left side of the stack of cell groups 110. Therefore, the front busbar 135 is positioned on the right front side relative to the stack of cell groups 110, and the rear busbar 145 is positioned on the left rear side relative to the stack of cell groups 110. However, the configuration of the positive electrode tabs 114 and negative electrode tabs 116 at the ends of the series-connected multiple cell groups sometimes varies depending on the number of cell groups 110 contained in the stack of cell groups 110. For example, consider the following situation: the positive electrode tabs 114 at the ends of multiple series-connected cell groups extend forward from the cell group 110 located on the right side of the stack of cell groups 110, and the negative electrode tabs 116 at the ends of multiple series-connected cell groups extend forward from the cell group 110 located on the left side of the stack of cell groups 110. In this case, the busbar electrically connected to the positive electrode tabs 114 at the ends of the multiple series-connected cell groups is positioned on the right front side relative to the stack of cell groups 110, and the busbar electrically connected to the negative electrode tabs 116 at the ends of the multiple series-connected cell groups is positioned on the left front side relative to the stack of cell groups 110.

[0070] The monomer housing 150 includes: a front plate 151, a rear plate 152, a left plate 153, a right plate 154, an upper plate 155, and a lower plate 156. Each plate is, for example, a metallic body such as aluminum.

[0071] The front panel 151 of the battery cell 110 covers the stacked structure of the battery cell 110 and the front part of the front voltage detection device 130. The rear panel 152 of the battery cell 110 covers the stacked structure of the battery cell 110 and the rear part of the rear voltage detection device 140. The left panel 153 of the battery cell 110 covers the left part of the stacked structure of the battery cell 110. The right panel 154 of the battery cell 110 covers the right part of the stacked structure of the battery cell 110. The upper panel 155 of the battery cell 110 covers the upper part of the stacked structure of the battery cell 110. The upper panel 155 of the battery cell 110 is provided with a plurality of gas vent holes 155a. Therefore, gas generated from the battery cell 110 can be discharged upwards towards the battery module 100 through the plurality of gas vent holes 155a. The plurality of gas vent holes 155a are arranged in multiple rows and multiple columns in the X and Y directions, respectively. However, the arrangement of the plurality of gas vent holes 155a is not limited to this example. Alternatively, the gas vent holes 155a may not be provided. The lower panel 156 of the battery cell 110 covers the lower part of the stacked structure of the battery cell 110. A thermally conductive adhesive 156a is disposed between the upper surface of the lower plate 156 of the cell and the lower surface of the laminate of the cell 110. Therefore, heat generated from the laminate of the cell 110 can dissipate downwards from the battery module 100 via the thermally conductive adhesive 156a.

[0072] Reference again Figures 1-4 Let's explain battery pack 10. Figures 2-4 The outline of the battery module 100 shown is schematically illustrated for use. Figure 5 The outline of the monomer container 150 is described. Therefore, Figures 2-4 The front, rear, left, right, upper, and lower surfaces of the battery module 100 shown correspond to... Figure 5 The front surface of the front panel 151, the rear surface of the rear panel 152, the left surface of the left panel 153, the right surface of the right panel 154, the upper surface of the upper panel 155, and the lower surface of the lower panel 156 are shown.

[0073] like Figure 2 As shown, the junction box 210 is positioned at the front relative to the four battery modules 100. A pair of connection terminals 212 are provided at the front of the junction box 210. Figure 1 As shown, the front end of the coupling terminal 212 protrudes forward from the front surface of the side frame 314. A pair of coupling terminals 212 and four battery modules 100 are electrically connected to each other via a junction box 210. Thus, in the electrical path, the four battery modules 100 are connected in series between a pair of coupling terminals 212.

[0074] The electronic devices disposed in front of the four battery modules 100 are not limited to the junction box 210. Electronic devices electrically connected to at least one battery module 100 may be disposed in front of the four battery modules 100, replacing or based on the junction box 210. Alternatively, the electronic devices disposed in front of the four battery modules 100 may be other battery modules different from these four battery modules 100.

[0075] like Figure 4 As shown, the wiring harness guide 220 is positioned above the support frame 316 between adjacent battery modules 100 in the Y direction. The wiring harness guide 220 guides and holds at least one of the wiring harnesses (not shown). The configuration of the wiring harness guide 220 is not limited to... Figure 4 The example shown. Furthermore, the wiring harness may also be located at a different position than where the wiring harness guide 220 is located. The wiring harness includes at least one wire. Examples of the wires included in the wiring harness include low-voltage wiring such as wiring that operates as a signal line, wiring that constitutes a circuit made up of a 12V power supply for the vehicle, voltage detection lines electrically connected to at least one of the front connector 134 and the rear connector 144 of the battery module 100, signal lines of the thermistors that detect the temperature of each battery cell 110 included in the battery module 100, and high-voltage wiring such as wiring for supplying power to the heaters that heat each battery cell 110 included in the battery module 100.

[0076] The lower module plate 312 extends approximately parallel to the horizontal direction. The side frame 314 is approximately perpendicular to the lower module plate 312. Viewed from the Z direction, the side frame 314 extends along the outer periphery of the lower module plate 312. Viewed from the Z direction, the support frame 316 forms a general frame surrounding each of the four battery modules 100.

[0077] The upper housing 320 is located above the lower housing 310 and covers the lower housing 310. The lower housing 310 and the upper housing 320 are mounted to each other via a sealing material such as rubber between the upper surface of the side frame 314 and the portion in the Z direction opposite to the upper surface of the side frame 314 of the lower housing 310. The lower housing 310 and the upper housing 320 define a receiving space for accommodating four battery modules 100, a junction box 210, and a wiring harness guide 220. Hereinafter, as needed, the receiving space defined by the lower housing 310 and the upper housing 320 will be referred to as the receiving space of the module housing 300. The receiving space of the module housing 300 is sealed from the outside of the module housing 300 when the lower housing 310 and the upper housing 320 are mounted to each other via the sealing material.

[0078] The gas discharge section 400 is disposed on the rear side of the side frame 314. The gas discharge section 400 includes, for example, a pressure relief device (PRD) such as a pressure relief valve. If the pressure in the housing space of the module housing 300 exceeds a given value, the gas discharge section 400 is activated, and gas is discharged from the housing space inside the module housing 300 via the gas discharge section 400.

[0079] The pressure within the housing 300 sometimes increases due to gas discharged from the battery module 100. Specifically, sometimes high-temperature gas is generated from the battery cell 110 due to an abnormality. The gas generated from the battery cell 110 is discharged upwards from the battery module 100 through multiple gas discharge ports 155a. Figure 3 As shown, a connecting space 350 exists within the accommodating space of the module housing 300. The connecting space 350 is a space above the upper surfaces of the four battery modules 100, communicating with the four battery modules 100 and the gas exhaust section 400. Gas exhausted from each battery module 100 reaches the gas exhaust section 400 via the connecting space 350.

[0080] Gas generated from the battery cell 110 can also be discharged from a gas discharge section different from the plurality of gas discharge holes 155a. For example, gas generated from the battery cell 110 can also be discharged from the gap between the front plate 151 and the upper plate 155 of the cell, the gap between the rear plate 152 and the upper plate 155 of the cell, the gap between the left plate 153 and the upper plate 155 of the cell, or the gap between the right plate 154 and the upper plate 155 of the cell. Gas discharged from these gaps is also discharged upwards towards the battery module 100 and reaches the gas discharge section 400 via the communication space 350.

[0081] like Figure 2 As shown, viewed from the Z direction, the two spacers 500 are arranged side-by-side along the Y direction, roughly symmetrically. One spacer 500 is located on the upper surface of the battery module 100 on the left front side. Hereinafter, as needed, the spacer 500 located on the upper surface of the battery module 100 on the left front side will be referred to as the left spacer 500. Figure 3 As shown, the left spacer 500 is disposed in the gap between the upper surface of the battery module 100 on the left front side and the lower surface of the upper housing 320. The other spacer 500 is disposed on the upper surface of the battery module 100 on the right front side. Hereinafter, as needed, the spacer 500 disposed on the upper surface of the battery module 100 on the right front side will be referred to as the right spacer 500. The right spacer 500 is disposed in the gap between the upper surface of the battery module 100 on the right front side and the lower surface of the upper housing 320.

[0082] The left spacer 500 will be described below. Unless otherwise specified, the matters described regarding the left spacer 500, except that the left spacer 500 and the right spacer 500 are arranged approximately symmetrically when viewed from the Z direction, can also be applied to the right spacer 500.

[0083] like Figure 2 As shown, viewed from the Z direction, the left spacer 500 is approximately L-shaped. The left spacer 500 includes a first spacer extension 510 and a second spacer extension 520. Hereinafter, as needed, the first spacer extension 510 and the second spacer extension 520 of the left spacer 500 will be referred to as the left first spacer extension 510 and the left second spacer extension 520, respectively.

[0084] like Figure 2 As shown, viewed from the Z direction, the first spacer extension 510 on the left extends in the Y direction along the outer edge of the front side of the upper surface of the battery module 100 on the left front side. The length of the first spacer extension 510 in the Y direction is approximately equal to the length of the upper surface of the battery module 100 on the left front side in the Y direction. Viewed from the Z direction, the second spacer extension 520 on the left extends in the X direction along the outer edge of the right side of the upper surface of the battery module 100 on the left front side. The length of the second spacer extension 520 in the X direction is shorter than the length of the upper surface of the battery module 100 on the left front side in the X direction. The shape of the first spacer extension 510 on the left is not limited to... Figure 2 The shape shown.

[0085] like Figure 2 As shown, viewed from the Z direction, the first spacer extension 510 on the left is positioned in front of the plurality of gas exhaust holes 155a of the battery module 100 on the left front side. Therefore, when gas is being discharged from the battery module 100 on the left front side, the first spacer extension 510 on the left side acts as a gas shield, blocking gas flowing in the opposite direction from the battery module 100 on the left front side to the gas exhaust section 400. Therefore, compared to the case where the first spacer extension 510 on the left side is not provided, the gas discharged from the battery module 100 on the left front side can be effectively moved toward the gas exhaust section 400, and the gas discharged from the battery module 100 on the left front side can be effectively discharged from the gas exhaust section 400.

[0086] The first spacer extension 510 on the left side can block not only the gas discharged from the battery module 100 on the front left side, but also the gas discharged from the battery module 100 on the rear left side. That is, when the gas is discharged from the battery module 100 on the rear left side, the first spacer extension 510 on the left side can act as a gas shield to block the gas flowing in the opposite direction from the battery module 100 on the rear left side to the gas discharge section 400. Therefore, compared with the case where the first spacer extension 510 on the left side is not provided, the gas discharged from the battery module 100 on the rear left side can be effectively moved toward the gas discharge section 400, and the gas discharged from the battery module 100 on the rear left side can be effectively discharged from the gas discharge section 400.

[0087] like Figure 2 As shown, viewed from the Z direction, the left-side first spacer extension 510 is located between the plurality of gas vent holes 155a of the left-front battery module 100 and the left portion of the junction box 210. Therefore, the left-side first spacer extension 510 acts as a gas shield, preventing gas from flowing from the left-front or left-rear battery module 100 to the junction box 210. Thus, the left-side first spacer extension 510 can protect the junction box 210 from the gas generated from the left-front or left-rear battery module 100.

[0088] like Figure 2 As shown, viewed from the Z direction, the second spacer extension 520 on the left is located on the right side relative to a portion of the gas exhaust hole 155a on the front side of the battery module 100 on the left front side. Therefore, the second spacer extension 520 on the left side acts as a gas shield, blocking gas flowing to the right relative to the direction from the battery module 100 on the left front side toward the gas exhaust section 400. Therefore, compared to the case without the second spacer extension 520 on the left side, the gas exhausted from the battery module 100 on the left front side can be effectively moved toward the gas exhaust section 400, and the gas exhausted from the battery module 100 on the left front side can be effectively discharged from the gas exhaust section 400.

[0089] like Figure 2 As shown, viewed from the Z direction, the second spacer extension 520 on the left is located between a portion of the gas exhaust port 155a on the front side of the left front battery module 100 and the front part of the right front battery module 100. Therefore, the second spacer extension 520 on the left acts as a gas shield, preventing gas from flowing from the left front battery module 100 to the right front battery module 100. Thus, the second spacer extension 520 on the left can protect the right front battery module 100 from the gas generated from the left front battery module 100.

[0090] The left-side spacer 500 is, for example, an elastomer with heat resistance and flame retardancy, such as foamed silicone. The material used for the spacer 500 is not limited to foamed silicone, as long as it possesses the desired heat resistance, flame retardancy, and resilience modulus. The left-side spacer 500 is compressed in the Z direction by the upper surface of the left front battery module 100 and the lower surface of the upper housing 320. Therefore, the left-side spacer 500 elastically deforms. Thus, compared to the case where the left-side spacer 500 does not elastically deform, it is difficult to create gaps between the lower surface of the left-side spacer 500 and the upper surface of the left front battery module 100, and between the upper surface of the left-side spacer 500 and the lower surface of the upper housing 320. Therefore, compared to the case where such gaps occur, it is easier to use the left-side spacer 500 to block gas. The material of the left-side spacer 500 is not limited to an elastomer. For example, the spacer 500 on the left side can also be a rigid body that will not elastically deform under compression from the upper surface of the battery module 100 on the left front side and the lower surface of the upper housing 320.

[0091] The method for fixing the left-side spacer 500 is not particularly limited. For example, the lower surface of the left-side spacer 500 and the upper surface of the battery module 100 can be pre-joined with each other using an adhesive or other bonding material. Alternatively, the upper surface of the left-side spacer 500 and the lower surface of the upper housing 320 can be pre-joined with each other using an adhesive or other bonding material. Alternatively, the lower and upper surfaces of the left-side spacer 500 may not be pre-joined with the upper surface of the battery module 100 and the lower surface of the upper housing 320 respectively.

[0092] As explained above, the spacer 500 serves as a gas shield that blocks gas flowing in a direction different from that from the battery module 100 to the gas discharge section 400. Therefore, when the spacer 500 is provided, compared to the case where the spacer 500 is not provided, the gas discharged from the battery module 100 can be effectively discharged from the gas discharge section 400.

[0093] As the heat-resistant sheet 610, commercially available heat-resistant sheets can be used, for example. As the heat-resistant sheet, fiber sheets or ceramic plates made by laminating fibers containing carbon, silicon dioxide, alumina, magnesium oxide, etc., together with silicone resin or fluorine resin can be used, but it is not limited to these. From the viewpoint of formability and heat resistance, the aforementioned fiber sheets with a heat resistance temperature of 1000°C or higher are particularly preferred. Figure 2As shown, the four upper heat-resistant sheets 610 and the four battery modules 100 overlap each other in the Z direction. Hereinafter, as needed, the upper heat-resistant sheet 610 located on the left front side among the four upper heat-resistant sheets 610 is referred to as the left front upper heat-resistant sheet 610, the upper heat-resistant sheet 610 located on the right front side among the four upper heat-resistant sheets 610 is referred to as the right front upper heat-resistant sheet 610, the upper heat-resistant sheet 610 located on the left rear side among the four upper heat-resistant sheets 610 is referred to as the left rear upper heat-resistant sheet 610, and the upper heat-resistant sheet 610 located on the right rear side among the four upper heat-resistant sheets 610 is referred to as the right rear upper heat-resistant sheet 610.

[0094] like Figure 3 As shown, the upper heat-resistant sheet 610 on the left front side covers the lower surface of the portion of the upper housing 320 that overlaps with the battery module 100 on the left front side in the Z direction. The same applies to the upper heat-resistant sheets 610 on the left rear side, the right front side, and the right rear side. Therefore, each upper heat-resistant sheet 610 becomes a heat-resistant body disposed around the lower surface of the upper housing 320 around the communicating space 350. Therefore, compared to the case where these upper heat-resistant sheets 610 are not provided, the temperature rise of the upper housing 320 caused by high-temperature gas passing through the communicating space 350 can be suppressed. For example, the lower surface of the upper housing 320 is sometimes coated with a material such as an anti-rust coating. If this material is exposed to high-temperature gas and burns through, there is a possibility that the burned-through material will come into contact with any part of the battery module 100. However, when the upper heat-resistant sheets 610 are provided, compared to the case where the upper heat-resistant sheets 610 are not provided, the possibility of the aforementioned material burning through due to high-temperature gas can be reduced.

[0095] There are no particular limitations on the installation method of the upper surface of the upper heat-resistant sheet 610 on the left front side and the lower surface of the upper housing 320. For example, the upper surface of the upper heat-resistant sheet 610 on the left front side and the lower surface of the upper housing 320 can be bonded to each other via an adhesive layer provided on the upper surface side of the upper heat-resistant sheet 610 on the left front side.

[0096] As the heat-resistant sheet 620, commercially available heat-resistant sheets can be used, for example. As the heat-resistant sheet, fiber sheets or ceramic plates made by laminating fibers containing carbon, silicon dioxide, alumina, magnesium oxide, etc., together with silicone resin or fluorine resin can be used, but it is not limited to these. From the viewpoint of formability and heat resistance, the aforementioned fiber sheets with a heat resistance temperature of 1000°C or higher are particularly preferred. Figure 2 As shown, viewed from the Z direction, the two lower heat-resistant sheets 620 are arranged side by side along the Y direction, roughly symmetrically. Hereinafter, as needed, the lower heat-resistant sheet 620 located on the left side of the two lower heat-resistant sheets 620 will be referred to as the left lower heat-resistant sheet 620, and the lower heat-resistant sheet 620 located on the right side of the two lower heat-resistant sheets 620 will be referred to as the right lower heat-resistant sheet 620.

[0097] The following describes the lower heat-resistant sheet 620 on the left. Unless otherwise specified, the matters described regarding the lower heat-resistant sheet 620 on the left and the lower heat-resistant sheet 620 on the right are also applicable to the lower heat-resistant sheet 620 on the right when viewed from the Z direction.

[0098] like Figure 2 as well as Figure 3 As shown, the lower heat-resistant sheet 620 on the left covers the upper surface of the rear portion of the battery module 100 on the left front side and the upper surface of the front portion of the battery module 100 on the left rear side. Therefore, the lower heat-resistant sheet 620 on the left becomes a heat-resistant body disposed around the communicating space 350 on the upper surface of the rear portion of the battery module 100 on the left front side and the upper surface of the front portion of the battery module 100 on the left rear side. Therefore, compared to the case where the lower heat-resistant sheet 620 on the left is not provided, the temperature rise of the rear portion of the battery module 100 on the left front side and the front portion of the battery module 100 on the left rear side caused by the high-temperature gas passing through the communicating space 350 can be suppressed.

[0099] like Figure 3 As shown, the lower heat-resistant sheet 620 on the left exposes multiple gas vent holes 155a of the battery module 100 on the front left and the battery module 100 on the rear left. Therefore, compared to the case where these gas vent holes 155a are covered by the lower heat-resistant sheet 620 on the left, gas can be effectively discharged from these gas vent holes 155a.

[0100] The front of the lower heat-resistant sheet 620 on the left side and the battery module 100 on the left front side. Figure 5 At least one of the rear tab group 118 and the rear voltage detection device 140 shown overlaps in the Z direction. Therefore, the lower heat-resistant sheet 620 on the left side can protect the tab group 118 and the rear voltage detection device 140 from the high-temperature gas passing through the communication space 350 above the rear of the battery module 100 on the left front side.

[0101] The rear of the lower heat-resistant sheet 620 on the left side and the battery module 100 on the left rear side. Figure 5 The rear tab group 118 and the front voltage detection device 130 shown overlap in the Z direction. Therefore, the lower heat-resistant sheet 620 on the left side can protect the tab group 118 and the front voltage detection device 130 from the high-temperature gas passing through the communication space 350 above the front of the battery module 100 on the left rear side.

[0102] like Figure 2 as well as Figure 3As shown, the lower heat-resistant sheet 620 on the left extends from the rear of the left front battery module 100 to the front of the left rear battery module 100. Therefore, a single lower heat-resistant sheet 620 can cover the upper surface of the rear of the left front battery module 100 and the upper surface of the front of the left rear battery module 100. Thus, compared to using different lower heat-resistant sheets 620 to cover the upper surfaces of the rear of the left front battery module 100 and the upper surfaces of the front of the left rear battery module 100, the number of components in the battery pack 10 can be reduced.

[0103] There are no particular limitations on the mounting method of the lower front surface of the left-side lower heat-resistant sheet 620 and the upper rear surface of the left front battery module 100. For example, the lower front surface of the left-side lower heat-resistant sheet 620 and the upper rear surface of the left front battery module 100 can be bonded together via an adhesive layer provided on the lower surface side of the left-side lower heat-resistant sheet 620. The same applies to the lower rear surface of the left-side lower heat-resistant sheet 620 and the upper front surface of the left rear battery module 100.

[0104] The configuration of the upper heat-resistant plate 610 and the lower heat-resistant plate 620 is not limited to Figure 2 as well as Figure 3 The example shown demonstrates that heat-resistant materials such as the upper heat-resistant sheet 610 and the lower heat-resistant sheet 620 can be at least partially disposed around the communicating space 350. When heat-resistant materials are provided, compared to the case where no heat-resistant materials are provided, it is possible to suppress the temperature rise around the communicating space 350 caused by high-temperature gas passing through the communicating space 350.

[0105] Figure 6 This is a top view of the battery pack 10A in the modified example, with the wiring harness guide and upper housing removed. Figure 7 This is a perspective view of the cell top plate 155 and the first heat-resistant sheet 610A involved in the modified example. The battery pack 10A involved in the modified example is the same as the battery pack 10 involved in the embodiment, except for the following points.

[0106] exist Figure 6 In this embodiment, the spacers corresponding to the two spacers 500 involved in the embodiment are removed. The battery pack 10A involved in the modified example is also the same as the battery pack 10 involved in the embodiment, and may have spacers corresponding to the two spacers 500 involved in the embodiment.

[0107] like Figure 6As shown, the modified battery pack 10A includes four first heat-resistant sheets 610A and six second heat-resistant sheets 620A. The four first heat-resistant sheets 610A and the four battery modules 100 overlap each other in the Z direction. Each first heat-resistant sheet 610A covers the upper surface of the peripheral portion of the plurality of gas vent holes 155a of each battery module 100. The six second heat-resistant sheets 620A include two front-side second heat-resistant sheets 620A in the X direction, two central-side second heat-resistant sheets 620A in the X direction, and two rear-side second heat-resistant sheets 620A in the X direction. One of the two front-side second heat-resistant sheets 620A in the X direction covers the front portion of the left front-side battery module 100. The other of the two front-side second heat-resistant sheets 620A in the X direction covers the front portion of the right front-side battery module 100. One side of the two second heat-resistant sheets 620A on the central side in the X direction covers the rear of the left front battery module 100 and the front of the left rear battery module 100. The other side of the two second heat-resistant sheets 620A on the central side in the X direction covers the rear of the right front battery module 100 and the front of the right rear battery module 100. One side of the two second heat-resistant sheets 620A on the rear side in the X direction covers the rear of the left rear battery module 100. The other side of the two second heat-resistant sheets 620A on the rear side in the X direction covers the rear of the right rear battery module 100.

[0108] Hereinafter, as needed, the second heat-resistant sheet 620A located on the left front side among the six second heat-resistant sheets 620A will be referred to as the left front side second heat-resistant sheet 620A, the second heat-resistant sheet 620A located on the right front side among the six second heat-resistant sheets 620A will be referred to as the right front side second heat-resistant sheet 620A, and the second heat-resistant sheet 620A located on the left center side among the six second heat-resistant sheets 620A will be referred to as the left center side second heat-resistant sheet 620A. 20A, the second heat-resistant sheet 620A located on the right center side among the 6 second heat-resistant sheets 620A is called the second heat-resistant sheet 620A on the right center side; the second heat-resistant sheet 620A located on the left rear side among the 6 second heat-resistant sheets 620A is called the second heat-resistant sheet 620A on the left rear side; and the second heat-resistant sheet 620A located on the right rear side among the 6 second heat-resistant sheets 620A is called the second heat-resistant sheet 620A on the right rear side.

[0109] refer to Figure 7 To illustrate the first heat-resistant sheet 610A involved in the modified example.

[0110] The first heat-resistant sheet 610A has a central opening 612A. Multiple gas vent holes 155a are exposed from the central opening 612A. Therefore, compared with the case where the first heat-resistant sheet 610A covers the multiple gas vent holes 155a, gas can be effectively discharged from the multiple gas vent holes 155a.

[0111] The left and right ends of the first heat-resistant sheet 610A are bent downwards at approximately right angles relative to the left and right edges of the upper unit plate 155, respectively. Therefore, the left and right ends of the first heat-resistant sheet 610A can cover the left and right edges of the upper unit plate 155. A pair of notches 614A are provided at the bent portions at the left and right edges of the upper unit plate 155 at the leading edge of the first heat-resistant sheet 610A. Similarly, a pair of notches 614A are provided at the bent portions at the left and right edges of the upper unit plate 155 at the trailing edge of the first heat-resistant sheet 610A. Therefore, compared to the case where these notches 614A are not provided, the left and right ends of the first heat-resistant sheet 610A can be bent more easily.

[0112] The front and rear portions of the upper surface of the unit upper plate 155 are exposed from the first heat-resistant sheet 610A. The portions of the front and rear portions of the upper surface of the unit upper plate 155 exposed from the first heat-resistant sheet 610A can be used as allowance for mounting the second heat-resistant sheet 620A.

[0113] refer to Figure 6 To illustrate the modified example, the first heat-resistant sheet 610A and the second heat-resistant sheet 620A are described.

[0114] Each first heat-resistant sheet 610A serves as a heat-resistant body disposed around the communicating space 350 on the upper surface of the peripheral portion of the plurality of gas exhaust holes 155a of each battery module 100. Therefore, compared with the case where each first heat-resistant sheet 610A is not provided, the temperature rise of the peripheral portion of the plurality of gas exhaust holes 155a of each battery module 100 caused by the high-temperature gas passing through the communicating space 350 can be suppressed.

[0115] The second heat-resistant sheet 620A on the left central side serves as a heat-resistant material for the upper surface of the rear portion of the battery module 100 on the left front side and the upper surface of the front portion of the battery module 100 on the left rear side, which are disposed around the communicating space 350. Therefore, compared with the case where the second heat-resistant sheet 620A on the left central side is not provided, the temperature rise of the rear portion of the battery module 100 on the left front side and the front portion of the battery module 100 on the left rear side caused by the high-temperature gas passing through the communicating space 350 can be suppressed.

[0116] The front of the second heat-resistant sheet 620A on the left center side and the battery module 100 on the left front side. Figure 5 At least one of the rear tab group 118 and the rear voltage detection device 140 shown overlaps in the Z direction. Therefore, the second heat-resistant sheet 620A on the left central side can protect the tab group 118 and the rear voltage detection device 140 from the high-temperature gas passing through the communicating space 350 above the rear of the battery module 100 on the left front side.

[0117] The rear of the second heat-resistant sheet 620A on the left central side is adjacent to the battery module 100 on the left rear side. Figure 5 At least one of the front tab group 118 and the front voltage detection device 130 shown overlaps in the Z direction. Therefore, the second heat-resistant sheet 620A on the left central side can protect the tab group 118 and the front voltage detection device 130 from the high-temperature gas passing through the communicating space 350 above the front of the battery module 100 on the left rear side.

[0118] The same applies to the second heat-resistant sheet 620A on the left central side as well as the second heat-resistant sheet 620A on the right central side.

[0119] The second heat-resistant sheet 620A on the left front side serves as a heat-resistant body on the upper surface of the front portion of the battery module 100, which is disposed around the communicating space 350. Therefore, compared to the case where the second heat-resistant sheet 620A on the left front side is not provided, the temperature rise of the front portion of the battery module 100 on the left front side caused by the high-temperature gas passing through the communicating space 350 can be suppressed.

[0120] The second heat-resistant sheet 620A on the left front side and the battery module 100 on the left front side. Figure 5 At least one of the front tab group 118 and the front voltage detection device 130 shown overlaps in the Z direction. Therefore, the second heat-resistant sheet 620A on the left front side can protect the tab group 118 and the front voltage detection device 130 from the high-temperature gas passing through the communicating space 350 above the front of the battery module 100 on the left front side.

[0121] The same applies to the second heat-resistant sheet 620A on the left front side as well as the second heat-resistant sheet 620A on the right front side.

[0122] The second heat-resistant sheet 620A on the left rear side serves as a heat-resistant body on the upper surface of the rear portion of the battery module 100, which is disposed around the communicating space 350. Therefore, compared to the case where the second heat-resistant sheet 620A on the left rear side is not provided, the temperature rise of the rear portion of the battery module 100 on the left rear side caused by the high-temperature gas passing through the communicating space 350 can be suppressed.

[0123] The second heat-resistant sheet 620A on the left rear side and the battery module 100 on the left rear side. Figure 5 At least one of the rear tab group 118 and the rear voltage detection device 140 shown overlaps in the Z direction. Therefore, the second heat-resistant sheet 620A on the left rear side can protect the tab group 118 and the rear voltage detection device 140 from the high-temperature gas passing through the communicating space 350 above the rear of the battery module 100 on the left rear side.

[0124] The same applies to the second heat-resistant sheet 620A on the left rear side as well as the second heat-resistant sheet 620A on the right rear side.

[0125] As described above, in this embodiment, the gas discharged from the battery module 100 can be effectively discharged using the spacer 500.

[0126] The embodiments and variations of the present invention have been described above with reference to the accompanying drawings. However, these are merely illustrative examples of the present invention, and various other structures besides those described above are also possible.

[0127] This application claims priority based on Japanese Patent Application No. 2023-094020, filed on June 7, 2023, and all of its disclosures are incorporated herein by reference.

[0128] Explanation of reference numerals in the attached figures

[0129] 10, 10A: Battery pack; 100: Battery module; 110: Battery cell; 112: External component; 114: Positive electrode tab; 116: Negative electrode tab; 118: Tab group; 120: Compression pad; 130: Front voltage detection device; 131: Front protection component; 131a: Front opening; 132: Front voltage detection terminal; 133: Front voltage detection line; 134: Front connector; 135: Front busbar; 140: Rear voltage detection device; 141: Rear protection component; 141a: Rear opening; 142: Rear voltage detection terminal; 143: Rear voltage detection line; 144: Rear connector; 145: Rear busbar; 150: Cell housing; 151: Cell front plate; 152: Cell rear plate; 153: 154: Left plate of unit; 155: Right plate of unit; 155: Upper plate of unit; 155a: Gas vent hole; 156: Lower plate of unit; 156a: Thermally conductive adhesive; 210: Junction box; 212: Connecting terminal; 220: Wire harness guide; 300: Module housing; 310: Lower housing; 312: Lower plate of module; 314: Side frame; 316: Support frame; 320: Upper housing; 350: Communicating space; 400: Gas vent; 500: Spacer; 510: First spacer extension; 520: Second spacer extension; 610: Upper heat-resistant sheet; 610A: First heat-resistant sheet; 612A: Central opening; 614A: Notch; 620: Lower heat-resistant sheet; 620A: Second heat-resistant sheet.

Claims

1. A battery pack comprising: a battery module; a housing that houses the battery module; a gas discharge portion that discharges a gas discharged from the battery module from the housing; and a heat-resistant body that is at least partially disposed around a space in the housing that communicates with the battery module and the gas discharge portion.

2. The battery pack according to claim 1, wherein the heat-resistant body covers at least a portion of the battery module.

3. The battery pack according to claim 2, wherein the battery module has: a battery cell having a tab; and a voltage detection device electrically connected to the tab, and the heat-resistant body overlaps at least one of the tab and the voltage detection device.

4. The battery pack according to claim 2, wherein the battery module has a gas discharge portion that discharges the gas, and the gas discharge portion is exposed from the heat-resistant body.

5. The battery pack according to any one of claims 1 to 4, wherein the housing further houses another battery module, and the heat-resistant body covers at least a portion of the other battery module.

6. The battery pack according to any one of claims 1 to 4, wherein the heat-resistant body covers at least a portion of the housing. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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