Battery pack

Abstract

A battery pack is provided with: a plurality of battery cells; a case main body having an opening portion; and a cover attached to the case main body so as to close the opening, the cover forming, together with the case main body, a space in which the plurality of battery cells are accommodated. The battery cell is provided with: an exterior body that includes a top surface facing the cap cover and accommodates the electrode body and the electrolyte; and a gas outflow valve that causes the gas to flow out from the interior of the exterior body through the top surface to the space when the pressure inside the exterior body becomes equal to or greater than a predetermined value. The battery pack is further provided with a metal or ceramic plate member having a main part disposed between the top surface and the cover in the space, and a fixing part extending from the main part and fixed thereto, the main part being provided with a plurality of through-holes.

Description

Technical Field

[0001] The invention relates to a battery pack. Background Art

[0002] For example, International Publication No. 2020 / 189590 discloses a battery pack comprising: a secondary battery; a frame that accommodates the secondary battery; and a plate-shaped reinforcement portion that extends from one end to the other end of the frame in the long side direction and is arranged in the height direction of the secondary battery to reinforce the frame. Summary of the invention

[0003] In the battery pack disclosed in International Publication No. 2020 / 189590 mentioned above, a frame (casing) that accommodates a secondary battery is composed of a main body in a rectangular box shape with an open top and a cover that covers the opening of the main body.

[0004] In such a battery pack, when a high-pressure gas flows out from the battery cell into the housing when the battery is abnormal, there is a concern that the cover may be damaged due to the gas flowing out of the battery cell colliding with the cover. In addition, the plate-shaped reinforcement portion arranged in the height direction of the secondary battery can function as a baffle to prevent the gas from directly colliding with the cover, but since it blocks the high-pressure gas, there is a concern that an excessive load will be applied to the fixed portion of the reinforcement portion.

[0005] Therefore, an object of the present invention is to solve the above-mentioned problems and to provide a battery pack that can be appropriately protected when gas is generated in a battery cell.

[0006] [1] A battery pack, wherein the battery pack comprises: a plurality of battery cells; a shell body having an opening; and a cover, the cover being mounted on the shell body in a manner to close the opening and forming a space together with the shell body to accommodate the plurality of battery cells, the battery cells comprising: an outer casing, the outer casing including a top surface facing the cover and accommodating an electrode body and an electrolyte; and a gas outflow valve, the gas outflow valve allowing gas to flow from the interior of the outer casing through the top surface to the space when the pressure inside the outer casing becomes greater than a specified value, and further comprising a metal or ceramic plate member, the plate member comprising a main portion arranged between the top surface and the cover in the space and a fixing portion extending from the main portion and fixed thereto, the main portion being provided with a plurality of through holes.

[0007] According to the battery pack constructed in this way, by blocking the gas flowing out of the gas outflow valve with the main part, it is possible to suppress the direct collision of the gas with the cover, and to prevent the cover from being damaged. In this case, by providing a plurality of through holes in the main part, the pressure on the plate member from the gas is reduced, and it is possible to prevent excessive load from being applied to the fixing part. Therefore, the battery pack can be properly protected when gas is generated in the battery cell.

[0008] [2] The battery pack according to [1], further comprising a duct that forms a gas flow path communicating with the space and discharges gas from the space.

[0009] According to the battery pack structured in this way, the speed at which the space is filled with gas (gas filling speed) is reduced by providing a plurality of through holes in the main portion, thereby ensuring sufficient time for exhausting the gas from the space through the duct and suppressing the increase in the internal pressure of the space.

[0010] [3] The battery pack according to [1] or [2], wherein the plurality of through holes are provided at positions not facing the gas outflow valve.

[0011] According to the battery pack structured in this way, it is possible to more effectively suppress the gas flowing out from the gas outflow valve from directly colliding with the cover.

[0012] [4] The battery pack according to any one of [1] to [3], wherein the plate member further includes a deformation portion that is provided between the main portion and the fixing portion and is elastically deformable.

[0013] According to the battery pack structured in this way, when the gas flowing out from the gas outflow valve is blocked by the main portion, the deformable portion is elastically deformed, and it is possible to more reliably prevent an excessive load from being applied to the fixing portion.

[0014] [5] A battery pack as described in any one of [1] to [4], wherein the battery pack further comprises a connector mounted on the casing body, and the plate member further comprises a shielding portion extending from the main portion to shield the connector from the battery cell.

[0015] According to the battery pack configured in this way, the shielding portion can prevent high-temperature gas from heading toward the connector, thereby reducing the heat load on the connector.

[0016] The foregoing and other objects, features, configurations and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a perspective view showing a battery pack according to an embodiment of the present invention.

[0018] Figure 2It is shown Figure 1 Exploded assembly diagram of the battery pack in .

[0019] Figure 3 It is a perspective view showing a battery cell.

[0020] Figure 4 is Figure 1 A cross-sectional view of the battery pack is schematically shown when viewed in the direction of arrows along line IV-IV in FIG.

[0021] Figure 5 This is a graph showing changes in the amount of gas in a space associated with gas generation in a battery cell.

[0022] Figure 6 It is shown Figure 4 A cross-sectional view of a first variant of the battery pack.

[0023] Figure 7 It is shown Figure 4 A cross-sectional view of a second variant of the battery pack.

[0024] Figure 8 It is shown Figure 7 A three-dimensional view of a modified example of the plate member in FIG.

[0025] Fig. 9 It is shown Figure 4 A cross-sectional view of a third variant of the battery pack.

[0026] Fig.10 It is shown Fig. 9 A three-dimensional view of the plate component in FIG.

[0027] Fig.11 It is shown Fig. 9 A cross-sectional view of a modified example of the battery pack.

[0028] Fig.12 It is shown Fig.11 A three-dimensional view of the plate component in FIG. DETAILED DESCRIPTION

[0029] Embodiments of the present invention will be described with reference to the accompanying drawings. In the drawings referred to below, the same or corresponding components are denoted by the same reference numerals.

[0030] Figure 1 It is a perspective view showing a battery pack according to an embodiment of the present invention. Figure 2 It is shown Figure 1 Exploded assembly diagram of the battery pack in . Figure 3 It is a perspective view showing a battery cell. Figure 4 is Figure 1 A cross-sectional view of the battery pack is schematically shown when viewed in the direction of arrows along line IV-IV in FIG.

[0031] Reference Figures 1 to 4 The battery pack 100 can be used as a driving power source for vehicles such as hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (PHEV) or pure electric vehicles (BEV).

[0032] In this specification, for the convenience of explaining the structure of the battery pack 100, the axis extending in the horizontal direction in the stacking direction of the plurality of battery cells 11 described later is referred to as the "Y axis", the axis extending in the horizontal direction in a direction orthogonal to the Y axis is referred to as the "X axis", and the axis extending in the vertical direction is referred to as the "Z axis". Figure 4 As shown, the battery pack 100 has a substantially symmetrical structure with respect to an imaginary plane 110 parallel to the Y-axis-Z-axis plane.

[0033] The battery pack 100 includes a plurality of battery cells 11. The plurality of battery cells 11 are stacked in the Y-axis direction. The battery cells 11 are lithium-ion batteries. The battery cells 11 are square and have a rectangular thin plate shape. The plurality of battery cells 11 are stacked in such a way that the Y-axis direction is the thickness direction of the battery cells 11.

[0034] The battery cell 11 has an outer casing 12. The outer casing 12 is composed of a rectangular parallelepiped frame, and forms the appearance of the battery cell 11. The outer casing 12 accommodates an electrode assembly and an electrolyte solution.

[0035] The exterior body 12 has a pair of first side surfaces 14 ( 14 j , 14 k ), a pair of second side surfaces 13 ( 13 j , 13 k ), a top surface 15 , and a bottom surface 16 .

[0036] The first side surface 14 is composed of a plane orthogonal to the X-axis. The first side surface 14 is parallel to the Y-axis direction which is the stacking direction of the battery cells 11. The first side surface 14j and the first side surface 14k face opposite sides in the X-axis direction. The second side surface 13 is composed of a plane orthogonal to the Y-axis. The second side surface 13 has the largest area among the multiple side surfaces of the outer body 12. The second side surface 13j and the second side surface 13k face opposite sides in the Y-axis direction. Each of the top surface 15 and the bottom surface 16 is composed of a plane orthogonal to the Z-axis. The top surface 15 faces upward. The top surface 15 faces the cover 21 described later. The bottom surface 16 faces downward.

[0037] The battery cell 11 further includes a gas outflow valve 17. The gas outflow valve 17 is provided on the top surface 15. The gas outflow valve 17 is provided at the center of the top surface 15 in the X-axis direction. When the pressure inside the outer casing 12 becomes higher than a predetermined value, the gas outflow valve 17 allows the gas to flow out from the inside of the outer casing 12 through the top surface 15 to the outside of the outer casing 12 (a space 20 described later).

[0038] The battery cell 11 further includes a pair of electrode terminals 18, which are a positive terminal 18P and a negative terminal 18N. The electrode terminal 18 is provided on the top surface 15. The positive terminal 18P and the negative terminal 18N are provided to be separated from each other in the X-axis direction. The positive terminal 18P and the negative terminal 18N are provided on both sides of the gas outflow valve 17 in the X-axis direction.

[0039] The plurality of battery cells 11 are stacked in the following manner: between the battery cells 11, 11 adjacent in the Y-axis direction, the second side faces 13j face each other, and the second side faces 13k face each other. Thus, in the Y-axis direction of the stacked plurality of battery cells 11, the positive terminals 18P and the negative terminals 18N are arranged alternately. Between the battery cells 11, 11 adjacent in the Y-axis direction, the positive terminals 18P and the negative terminals 18N arranged in the Y-axis direction are connected to each other by a bus bar not shown. The plurality of battery cells 11 are electrically connected to each other in series.

[0040] In addition, the battery cell in the present invention is not limited to a square shape, but may also be a cylindrical shape. For example, a plurality of battery cells are arranged at intervals in the X-axis-Y-axis plane in an upright position with the cylindrical axis of each battery cell extending in the Z-axis direction. In this case, the gas outflow valve may also be provided on the inner side of the sealing body constituting the top surface of the battery cell.

[0041] like Figure 2 As shown, a single cell stack 120 is formed by a plurality of battery cells 11 stacked in the Y-axis direction. The single cell stack 120 is in the shape of a rectangular parallelepiped. The length of the single cell stack 120 in the Y-axis direction is greater than the length of the single cell stack 120 in the Z-axis direction, and greater than the length of the single cell stack 120 in the X-axis direction. The single cell stack 120 has a rectangular shape in which the Y-axis direction is the long side direction and the X-axis direction orthogonal to the Y-axis direction is the short side direction when viewed from above along the Z-axis direction. In addition, the single cell stack 120 arranged in the battery pack 100 is not limited to one row, but may be two or more rows.

[0042] The battery pack 100 also has a pair of end plates 91 and a pair of restraining rods 66 ( Figure 2 The diagram is omitted, see Figure 4). A pair of end plates 91 are respectively arranged at both ends of the monomer stack 120 (multiple battery cells 11) in the Y-axis direction. A pair of restraint rods 66 are arranged at both ends of the monomer stack 120 in the X-axis direction. The restraint rods 66 extend in the Y-axis direction and are connected to the pair of end plates 91 at both ends thereof. The multiple battery cells 11 are held together by the pair of end plates 91 and the pair of restraint rods 66.

[0043] The battery pack 100 further includes a shell body 31 and a cover 21. The shell body 31 and the cover 21 are made of metal. The shell body 31 and the cover 21 are formed of, for example, aluminum. The shell body 31 has an opening 30. The opening 30 opens upward. The cover 21 is mounted on the shell body 31 in a manner that closes the opening 30. The cover 21 and the shell body 31 together form a space 20 for accommodating a plurality of battery cells 11.

[0044] The housing body 31 has a bottom 51, a pair of first side portions 32, and a pair of second side portions 36. The bottom 51 has a wall shape in which the Z-axis direction is the thickness direction and is arranged along the X-axis-Y-axis plane. The bottom 51 has a rectangular shape when viewed from above along the Z-axis direction. The monomer stack 120 is placed on the bottom 51. A cooling plate 61 is inserted between the bottom 51 and the monomer stack 120. The cooling plate 61 is provided with a refrigerant passage 62 extending in the Y-axis direction.

[0045] A pair of first side portions 32 and a pair of second side portions 36 stand up from the periphery of the bottom portion 51. The pair of first side portions 32 face each other in the X-axis direction with the space 20 interposed therebetween. The first side portion 32 presents a wall shape in which the X-axis direction becomes the thickness direction and is arranged along the Y-axis-Z-axis plane. The pair of second side portions 36 face each other in the Y-axis direction with the space 20 interposed therebetween. The second side portion 36 presents a wall shape in which the Y-axis direction becomes the thickness direction and is arranged along the X-axis-Z-axis plane.

[0046] The bottom portion 51 is fastened to the pair of first side portions 32 and the pair of second side portions 36 by a plurality of bolts 52. The present invention is not limited to this configuration, and the bottom portion 51, the pair of first side portions 32, and the pair of second side portions 36 may be integrally formed of metal.

[0047] The space 20 is formed on the bottom 51 at a position surrounded by the pair of first side portions 32 and the pair of second side portions 36. The opening 30 is defined by the upper ends of the pair of first side portions 32 and the pair of second side portions 36. The space 20 is open to the space outside the housing body 31 through the opening 30.

[0048] The housing body 31 further includes a first flange portion 33. The first flange portion 33 extends in a flange shape in the surface direction of the X-axis-Y-axis plane from the upper ends of the pair of first side portions 32 and the pair of second side portions 36. The first flange portion 33 is provided in a frame shape along the upper ends of the pair of first side portions 32 and the pair of second side portions 36.

[0049] The cover 21 has a cover body 22 and a second flange 24. The cover body 22 constitutes the main part of the cover 21 and closes the opening 30. The cover body 22 has a tray shape with the Z-axis direction being the depth direction and opening downward. The second flange 24 extends in a flange shape from the lower end of the cover body 22 in the surface direction of the X-axis-Y-axis plane. The second flange 24 is arranged in a frame shape along the lower end of the cover body 22. The second flange 24 overlaps with the first flange 33 in the Z-axis direction. The first flange 33 and the second flange 24 are fastened to each other by a plurality of bolts 26, whereby the cover 21 is mounted on the housing body 31.

[0050] The battery pack 100 also has a plate member 41. The plate member 41 is formed of a material having a heat resistance to such an extent that it does not deform even when exposed to high-temperature gas or flames generated by the battery cell 11, and is preferably made of metal or ceramic. The plate member 41 is formed of, for example, a metal such as carbon steel, stainless steel, copper, aluminum, or titanium, or a ceramic such as alumina, zirconia, or silica. The plate member 41 may also be a member obtained by coating a resin material on the surface of these materials. The thickness of the plate member 41 is smaller than the thickness of the cover 21.

[0051] The plate member 41 has a main portion 42. The main portion 42 is provided in the space 20. The main portion 42 is arranged between the top surface 15 of the battery cell 11 and the cover 21 in the space 20. The main portion 42 faces the top surface 15 in the Z-axis direction. The main portion 42 faces the gas outflow valve 17 in the Z-axis direction. The main portion 42 faces the electrode terminal 18 (positive terminal 18P, negative terminal 18N) in the Z-axis direction. The main portion 42 is provided above the single-cell laminate 120 (battery cell 11).

[0052] The length of the main portion 42 in the X-axis direction is greater than the length of the cell stack 120 (battery cell 11) in the X-axis direction. The length of the main portion 42 in the Y-axis direction is greater than the length of the cell stack 120 in the Y-axis direction. The main portion 42 has a rectangular shape with the Y-axis direction as the long side direction and the X-axis direction as the short side direction when viewed from above along the Z-axis direction. The range of the cell stack 120 when viewed from above along the Z-axis direction is included in the range of the main portion 42 when viewed from above along the Z-axis direction.

[0053] The distance L between the top surface 15 and the main portion 42 in the Z-axis direction decreases as the distance from the gas outflow valve 17 in the X-axis direction is reduced. The distance L between the top surface 15 and the main portion 42 in the Z-axis direction is the largest at a position on the virtual plane 110, and decreases as the distance from the virtual plane 110 in the X-axis direction is reduced. The distance L between the top surface 15 and the main portion 42 in the Z-axis direction is constant regardless of the position in the Y-axis direction. The main portion 42 is inclined with respect to each direction of the X-axis direction and the Z-axis direction.

[0054] The battery pack 100 is cut along the X-axis-Z-axis plane. Figure 4 In the cross-sectional view in FIG. 4 , the main portion 42 has a curved cross section. The main portion 42 may also have an arc cross section formed with a certain curvature. The main portion 42 may also have a straight cross section.

[0055] The plate member 41 further includes a guide portion 44 and a fixing portion 45. The guide portion 44 extends from the periphery of the main portion 42 toward the bottom portion 51 in the Z-axis direction. Figure 4 In the cross-sectional view in FIG, the guide portion 44 extends from the peripheral edge of the main portion 42 toward the duct 70 described later. The guide portion 44, together with the main portion 42, has a tray shape with the Z-axis direction being the depth direction and opening downward.

[0056] The fixing portion 45 is extended from the main portion 42. The fixing portion 45 is provided along the periphery of the guide portion 44 when viewed from above in the Z-axis direction. The fixing portion 45 extends from the lower end of the guide portion 44 in a convex shape in the surface direction of the X-axis-Y-axis plane. The fixing portion 45 is provided in a frame shape along the lower end of the guide portion 44.

[0057] The fixing portion 45 is fixed. The fixing portion 45 is a fixing portion (connecting portion) of the plate member 41 for supporting the main portion 42 in the space 20. The fixing portion 45 is clamped by the housing body 31 and the cover 21. The fixing portion 45 is inserted between the first flange portion 33 and the second flange portion 24. The fixing portion 45 receives a tightening force generated by the plurality of bolts 26 between the first flange portion 33 and the second flange portion 24.

[0058] In this embodiment, the fixing portion 45 corresponds to the gasket 46 for sealing between the housing body 31 and the cover 21. That is, the main portion 42 and the gasket 46 are integrally formed by a metal or ceramic plate. According to such a structure, the number of components of the battery pack 100 can be reduced or the assembly man-hours of the battery pack 100 can be reduced.

[0059] The space 20 is divided into a space 20A and a space 20B by the plate member 41. The space 20B is surrounded by the plate member 41 and the cover 21. The space 20A is surrounded by the plate member 41 and the casing body 31. A plurality of battery cells 11 are accommodated in the space 20A.

[0060] The main part 42 is provided with a plurality of through holes 43. The through holes 43 penetrate the main part 42. The plurality of through holes 43 are arranged at intervals from each other. When viewed along the Z-axis direction, the plurality of through holes 43 are arranged at intervals from each other in the Y-axis direction and the X-axis direction. The plurality of through holes 43 are arranged at positions that are not opposed to the gas outflow valve 17 in the Z-axis direction. The space 20A and the space 20B are connected to each other through the plurality of through holes 43.

[0061] The battery pack 100 further includes a duct 70 . The duct 70 is provided facing the first side surface 14 of the battery cell 11 . The duct 70 forms a gas flow path 72 . The gas flow path 72 communicates with the space 20 . The duct 70 discharges the gas flowing out of the gas outflow valve 17 from the space 20 .

[0062] The housing body 31 further includes a rib 34. The rib 34 protrudes from the first side portion 32 in the X-axis direction and extends in a rib shape along the periphery of the first side portion 32. The duct 70 includes a pair of duct covers 71. The pair of duct covers 71 are respectively mounted on the pair of first side portions 32. The duct covers 71 are mounted on the first side portion 32 in a manner that abuts against the rib 34 in the X-axis direction.

[0063] The duct cover 71 forms a gas flow passage 72 together with the first side portion 32. A gas flow hole 35 is provided in the first side portion 32. The gas flow hole 35 is composed of a hole penetrating the first side portion 32, so that the space 20 (20A) and the gas flow passage 72 are connected. The gas flow passage 72 extends in the Y-axis direction and is open at one end thereof.

[0064] Assume the following situation: when a battery abnormality such as an internal short circuit of the battery cell 11 occurs, a flammable gas is generated inside the outer casing 12. The gas is discharged into the space 20 (20A) through the top surface 15 provided with the gas outflow valve 17 ( Figure 4 The gas collides with the plate member 41 and is guided by the main portion 42, thereby flowing from the central portion of the space 20 (20A) in the X-axis direction to both ends, and is further guided by the guide portion 44, thereby flowing downward through the gap between the single layer stack 120 and the first side portion 32 ( Figure 4 The gas flows as indicated by arrows B and C in FIG. 1 ). The gas is discharged from the space 20 (20A) through the gas flow holes 35 to the gas flow passage 72 ( Figure 4 The gas flows in the Y-axis direction through the gas flow path 72 and is discharged to the outside of the pipe 70 ( Figure 1 Gas flow as shown by arrow E in FIG.

[0065] As the capacity of batteries has increased in recent years, the amount of gas generated in the battery cells 11 has increased. As a result, high-pressure gas may be ejected from the battery cells 11, or the gas may become hot due to the increased pressure of the gas, or spontaneous combustion may occur. In response to such situations, the battery pack 100 of this embodiment is provided with a plate member 41.

[0066] In the space 20, the main part 42 disposed between the top surface 15 of the battery cell 11 and the cover 21 blocks the high-pressure gas ejected from the battery cell 11 or the shock wave accompanying the natural fire, thereby preventing the cover 21 from being damaged. In addition, the main part 42 also has a heat shielding function to prevent the cover 21 from being exposed to the high-temperature gas. In this case, a part of the gas blocked by the main part 42 enters the space 20B from the space 20A through the plurality of through holes 43. In this way, the pressure received by the plate member 41 from the gas can be reduced, and an excessive load can be prevented from being applied to the fixing part 45. In this way, the cover 21 and the plate member 41 can be prevented from being damaged.

[0067] In this embodiment, the plurality of through holes 43 are provided at positions not facing the gas outflow valve 17. This configuration can more effectively prevent the high-pressure gas ejected from the battery cell 11 or the shock wave accompanying the spontaneous combustion from directly colliding with the cover 21.

[0068] Figure 5 This is a graph showing the change in the amount of gas in the space when gas is generated in the battery cell. Figure 5 , the change in the amount of gas in the space 20 of the present embodiment is shown by a solid line 310. The change in the amount of gas in the space 20 in the comparative example is shown by a dotted line 320. In the comparative example, the plurality of through holes 43 are not provided in the plate member 41. The area Sa in the graph is equal to the area Sb in the graph.

[0069] The gas ejected from the battery cell 11 flows from the center of the space 20 (20A) in the X-axis direction to both ends, and then passes through the gap between the cell stack 120 and the first side portion 32 to finally reach the gas flow hole 35, so that the gas fills the space 20 just after the gas is generated. In this case, the internal pressure of the space 20 rises significantly, which may cause damage to the shell body 31 and the cover 21 that form the space 20. In contrast, in the present embodiment, a part of the gas blocked by the main portion 42 of the plate member 41 flows from the space 20A to the space 20B through the plurality of through holes 43, which can reduce the speed at which the gas fills the space 20 just after the gas is generated. As a result, the increase in the internal pressure of the space 20 can be suppressed, and the damage to the shell body 31 and the cover 21 can be more reliably prevented.

[0070] Figure 6 It is shown Figure 4A cross-sectional view of a first variant of the battery pack. Figure 7 It is shown Figure 4 A cross-sectional view of a second variation of the battery pack in FIG. Figure 6 as well as Figure 7 In these modified examples, the plate member 41 and the gasket 46 are provided separately. Figure 6 In the modified example, the fixing portion 45 is fixed to the housing body 31. Figure 7 In the modified example, the fixing portion 45 is fixed to the end plate 91 .

[0071] Figure 8 It is shown Figure 7 A perspective view of a modified example of the plate member in FIG. Figure 8 In this modification, the plate member 41 further includes a deformation portion 81. The deformation portion 81 is provided between the main portion 42 and the fixing portion 45. The deformation portion 81 is provided at both ends of the main portion 42 in the Y-axis direction.

[0072] The deformable portion 81 is configured to be elastically deformable and extends in a wave-like manner in the Y-axis direction while changing its direction to one direction and another direction along the Z-axis direction.

[0073] According to such a configuration, when the gas ejected from the battery cell 11 is blocked by the main portion 42 , the deformable portion 81 is elastically deformed. This can more reliably prevent an excessive load from being applied to the fixing portion 45 .

[0074] Fig. 9 It is shown Figure 4 A cross-sectional view of a third variant of the battery pack. Fig.10 It is shown Fig. 9 A perspective view of the plate member in FIG. Fig. 9 as well as Fig.10 In this modification, the plate member 41 and the gasket 46 are provided separately. The fixing portion 45 is fixed to the cover 21 .

[0075] The main part 42 is provided along the cover body 22. The fixing part 45 is provided in the surface of the main part 42. When the main part 42 is viewed along the Z-axis direction, the plurality of fixing parts 45 are provided at intervals from each other in the X-axis direction and the Y-axis direction. A bolt 83 is inserted through the fixing part 45. The bolt 83 is screwed with a nut 84 provided on the cover body 22.

[0076] The plate member 41 further includes a peripheral edge portion 86. The peripheral edge portion 86 is bent toward the peripheral edge of the main portion 42 toward the cover body 22. The peripheral edge portion 86 abuts against the cover body 22, thereby providing a space between the main portion 42 and the cover body 22.

[0077] Fig.11 It is shown Fig. 9A cross-sectional view of a modified example of the battery pack. Fig.12 It is shown Fig.11 A perspective view of the plate member in FIG. Fig.11 as well as Fig.12 The battery pack 100 further includes a connector 96. The connector 96 is mounted on the housing body 31. The connector 96 is mounted on the pair of second side portions 36. In the connector 96, various wirings such as power lines and voltage detection lines are inserted between the space 20 and the outside.

[0078] In the present modification, the plate member 41 further includes a shielding portion 88. The shielding portion 88 is provided to extend from the main portion 42. The shielding portion 88 is provided to shield the connector 96 and the battery cell 11.

[0079] The shielding portion 88 is provided at both ends of the main portion 42 in the Y-axis direction. The shielding portion 88 extends from the main portion 42 in a direction approaching the bottom portion 51 in the Z-axis direction. The shielding portion 88 is arranged in a gap between the connector 96 and the end plate 91 in the Y-axis direction. The connector 96 faces the shielding portion 88 in the Y-axis direction.

[0080] According to such a configuration, the shielding portion 88 can prevent high-temperature gas from heading toward the connector 96. Thus, the heat load on the connector 96 can be reduced.

[0081] In addition, the supporting structures of the various plate members 41 described above and the structures of the deforming portion 81 and the shielding portion 88 may be appropriately combined. Figure 6 The form shown is supported by a plate member 41 combination Figure 8 The structure of the deformation portion 81 in FIG.

[0082] To summarize the configuration of the battery pack 100 according to the embodiment of the present invention described above, the battery pack 100 according to the present embodiment includes: a plurality of battery cells 11; a housing body 31 having an opening 30; and a cover 21 attached to the housing body 31 so as to close the opening 30 and forming a space 20 for housing the plurality of battery cells 11 together with the housing body 31. The battery cells 11 include: an outer casing 12 including a top surface 15 facing the cover 21 and housing an electrode body and an electrolyte; and a gas outflow valve 17 for allowing gas to flow from the inside of the outer casing 12 to the space 20 through the top surface 15 when the pressure inside the outer casing 12 becomes higher than a predetermined value. The battery pack 100 further includes a plate member 41 made of metal or ceramic, the plate member 41 including a main portion 42 disposed between the top surface 15 and the cover 21 in the space 20 and a fixing portion 45 extending from the main portion 42 and fixed thereto, and a plurality of through holes 43 are provided in the main portion 42.

[0083] According to the battery pack 100 of the embodiment of the present invention configured in this manner, it is possible to prevent the battery pack 100 from being damaged when gas is generated in the battery cells 11 .

[0084] Although the embodiments of the present invention have been described, the embodiments disclosed this time should be considered to be illustrative in all aspects and not restrictive. The scope of the present invention is indicated by the claims, and it is intended to include all modifications within the meaning and scope equivalent to the claims.

Claims

1. A battery pack, wherein: The battery pack has: Multiple battery cells; a housing body having an opening; and a cover, which is mounted on the housing body in a manner to close the opening and forms a space for accommodating the plurality of battery cells together with the housing body; The battery cell has: an outer casing, the outer casing including a top surface facing the cover and accommodating the electrode body and the electrolyte; and a gas outflow valve that allows gas to flow out of the space from the interior of the outer casing through the top surface when the pressure inside the outer casing becomes greater than a predetermined value, Furthermore, the battery pack further includes a metal or ceramic plate member having a main portion disposed between the top surface and the cover in the space and a fixing portion extending from and fixed to the main portion, wherein the main portion is provided with a plurality of through holes.

2. The battery pack according to claim 1, wherein: The battery pack further includes a duct that forms a gas flow path communicating with the space and discharges gas from the space.

3. The battery pack according to claim 1 or 2, wherein: The plurality of through holes are provided at positions not facing the gas outflow valve.

4. The battery pack according to claim 1 or 2, wherein: The plate member further includes a deformation portion which is provided between the main portion and the fixing portion and is elastically deformable.

5. The battery pack according to claim 1 or 2, wherein: The battery pack further comprises a connector mounted on the housing body. The plate member further includes a shielding portion extending from the main portion to shield the connector and a space between the battery cells.

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