Battery device

Abstract

The present invention provides a battery device that allows for easy and secure attachment of a heat-resistant insulating material to the battery module, and in which the heat-resistant insulating material is less likely to detach from the battery module even when exposed to high temperatures. [Solution] The battery module 40, 60 has a plurality of battery cells 48 arranged in a predetermined direction and a module case 42 that houses the plurality of battery cells, a heat-resistant insulating member 65 that is attached to the battery module so as to cover a first smoke exhaust hole formed in the module case and has a connection part 75 having an insertion groove, and a fixing member 85 that is detachably fitted into the insertion groove and supported by a fixing body.

Description

[Technical Field]

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

[0002] Patent Document 1 below discloses a battery device in which a heat-resistant layer facing the first smoke exhaust hole (emergency vent opening) of a battery cell is provided on an inner surface of a housing (battery case) that houses a battery module having a plurality of battery cells. [Prior Art Literature] [Patent Literature]

[0003] [Patent Document 1] Japanese National Publication of International Patent Application No. 2021-527914 [Summary of the Invention] [Problem to be Solved by the Invention]

[0004] A heat-resistant insulating member having heat resistance and electrical insulation can be attached to a battery cell. For example, the heat-resistant insulating member can be attached to the battery cell using double-sided adhesive tape. In this case, the heat-resistant insulating member suppresses contact of high-temperature debris discharged from the first smoke exhaust hole of another battery cell with the battery cell.

[0005] However, when the heat-resistant insulating member comes into contact with high-temperature debris, the chemical adhesive force of the double-sided adhesive tape decreases due to the heat of the debris, and there is a risk that the heat-resistant insulating member may peel off from the battery cell.

[0006] In view of the above facts, an object of the present invention is to obtain a battery device in which the heat-resistant insulating member can be easily and firmly attached to the battery module, and the heat-resistant insulating member is less likely to fall off from the battery module even when exposed to high temperatures. [Means for Solving the Problem]

[0007] The battery device of the first embodiment comprises a battery module having a plurality of battery cells arranged in a predetermined direction and a module case housing the plurality of battery cells; a heat-resistant insulating member mounted on the battery module so as to cover a first smoke exhaust hole formed in the module case and having a connection portion with an insertion groove; and a fixing member detachably fitted into the insertion groove and supported by a fixing body.

[0008] In the battery device of the first embodiment, a fixing member supported by a fixed body is detachably fitted into the insertion groove of the connection portion of the heat-resistant insulating member, which is mounted on the battery module so as to cover the first smoke exhaust hole. Therefore, the heat-resistant insulating member can be attached to the battery module easily and securely. Furthermore, since the insertion groove of the connection portion of the heat-resistant insulating member is mechanically coupled to the fixing member supported by the fixed body, the heat-resistant insulating member is less likely to fall off the battery module even when the battery device is placed under high temperatures.

[0009] In the battery device of the second embodiment, when the direction along a predetermined straight line is defined as the first direction, one end of the insertion groove in the first direction is open.

[0010] In the second embodiment, the insertion groove of the connection portion of the battery device allows for the mechanical connection of a fixed body facing the connection portion in the first direction with a heat-resistant insulating member using the fixed member.

[0011] In the third embodiment of the battery device, when the direction perpendicular to the first direction is defined as the second direction, both ends of the insertion groove in the second direction are open.

[0012] In the battery device of the third embodiment, the fixing member can be inserted into or removed from the insertion groove by moving the fixing member relative to the connection part in a second direction.

[0013] In the fourth embodiment, when the third direction is defined as the direction perpendicular to the first and second directions in the second or third embodiment, the connecting portion comprises a first plate-shaped portion and a second plate-shaped portion facing the first plate-shaped portion in the third direction such that an insertion groove is formed between the first plate-shaped portion and the second plate-shaped portion.

[0014] According to the battery device of the fourth embodiment, a connection part having an insertion groove can be realized with a simple configuration.

[0015] In the fifth embodiment of the battery device, the first plate-shaped portion and the second plate-shaped portion are elastically deformable in the third direction, and the dimension of the gap between the first plate-shaped portion and the second plate-shaped portion in the third direction when the first plate-shaped portion and the second plate-shaped portion are in a free state is smaller than the dimension of the fixing member in the third direction.

[0016] According to the battery device of the fifth embodiment, the fixing member and the connecting part can be mechanically connected easily and reliably.

[0017] In the sixth embodiment, the battery device, in the third embodiment, comprises a heat-resistant insulating member having a base facing the first smoke exhaust hole from above, and a pair of flanges that are separated from each other in the vertical direction and in the second direction perpendicular to the first direction, the upper part of the module case is located between the pair of flanges, and the pair of flanges are in contact with the upper part of the module case.

[0018] According to the battery device of the sixth embodiment, it is possible to prevent the heat-resistant insulating member from moving relative to the module case in a second direction.

[0019] In the seventh embodiment of the battery device, the connection portion is provided at one end of the base in the first direction, and a fixing bracket is fixed to the bottom plate portion of the battery case that houses the battery module, the heat-resistant insulating member, and the fixing member, and to the other end of the base in the first direction.

[0020] According to the battery device of the seventh aspect, it becomes possible to strengthen the mounting state of the heat-resistant insulating member to the battery module.

[0021] In the battery device of the eighth aspect, in any one of the first to third aspects, the connecting portion is formed of mica.

[0022] In the battery device of the eighth aspect, since the connecting portion is formed of mica, it is easy to manufacture the heat-resistant connecting portion at low cost.

[0023] In the battery device of the ninth aspect, in any one of the first to eighth aspects, a second smoke exhaust hole facing the first smoke exhaust hole is formed in the heat-resistant insulating member.

[0024] In the battery device of the ninth aspect, debris discharged from the battery cell and discharged to the outside of the battery module through the first smoke exhaust hole can be discharged to the outside of the heat-resistant insulating member through the second smoke exhaust hole.

[0025] In the battery device of the tenth aspect, in any one of the first to ninth aspects, the fixing member is made of metal.

[0026] In the battery device of the tenth aspect, the metal fixing member is covered by a part of the connecting portion. Therefore, an increase in temperature of the fixing member caused by the heat of high-temperature debris discharged from the battery cell can be suppressed by a part of the connecting portion.

[0027] In the battery device of the eleventh aspect, in any one of the first to tenth aspects, the battery device includes a plurality of the battery modules, and the connecting portion of the heat-resistant insulating member attached to at least one of the battery modules serves as the fixed body.

[0028] In the battery device of the eleventh aspect, the heat-resistant insulating member can be easily and firmly attached to each of two adjacent battery modules.

[0029] In the twelfth embodiment of the battery device, in any of the first to eleventh embodiments, the fixing member is fixed to the battery module to which the heat-resistant insulating member having the connecting portion, which is the fixing body, is attached.

[0030] According to the battery device of the twelfth embodiment, heat-resistant insulating members can be more easily attached to each of two adjacent battery modules.

[0031] In the 13th embodiment of the battery device, the battery case housing the battery module, the heat-resistant insulating member, and the fixing member is the fixing body, as can be found in any of the first to 12 embodiments.

[0032] In the battery device of the 13th embodiment, the battery case and the heat-resistant insulating member can be mechanically connected using a fixing member supported by the battery case. [Effects of the Invention]

[0033] As described above, the battery device according to the present invention has the excellent effect of allowing the heat-resistant insulating member to be easily and securely attached to the battery module, and preventing the heat-resistant insulating member from falling off the battery module even when exposed to high temperatures. [Brief explanation of the drawing]

[0034] [Figure 1] This is a cross-sectional view taken at the center in the width direction of a vehicle equipped with a battery pack according to the embodiment. [Figure 2] This is a schematic disassembled perspective view of the battery pack. [Figure 3] This is a schematic perspective view of the battery module and heat-resistant insulating material in a separated state. [Figure 4] This is a schematic disassembled perspective view of a battery module. [Figure 5] This is a schematic exploded perspective view of a heat-resistant insulating material. [Figure 6] This is a schematic cross-sectional view of the connection point between two adjacent battery modules. [Figure 7]This is a schematic cross-sectional view of a modified heat-resistant insulating member, a rear plate portion of the lower case, and a fixing member. [Modes for carrying out the invention]

[0035] The battery pack according to the embodiment will be described below with reference to the attached drawings. Note that the arrows UP, FR, and LH in each figure indicate the upper side in the vehicle's vertical direction (third direction), the front side in the vehicle's longitudinal direction (first direction), and the left side in the vehicle's lateral direction (predetermined direction) (second direction), respectively.

[0036] As shown in Figures 1 and 2, the battery pack (battery device) 20 of this embodiment is mounted on a vehicle (electric vehicle) 10. The vehicle 10 of this embodiment is an electric vehicle (BEV: Battery Electric Vehicle).

[0037] The vehicle 10 comprises a pair of left and right front wheels 11F, a pair of left and right rear wheels 11R, a pair of left and right rockers 12 which are part of the vehicle body frame and extend in the longitudinal direction of the vehicle, and a pair of front and rear cross members 14 which are part of the vehicle body frame and extend in the vehicle width direction (left and right direction), with both ends fixed to the left and right rockers 12.

[0038] The battery pack 20 of this embodiment includes a battery case 22, a battery module 40, and a battery module 60. Power from the battery pack 20 (battery cell 43) is supplied, for example, to an electric motor (not shown) that provides driving force to the front wheel 11F and the rear wheel 11R.

[0039] As shown in Figures 2 and 3, the battery case 22 has a lower case 24 and an upper case 35.

[0040] The lower case 24 is a hollow body with an opening 25 formed on its upper surface. The lower case 24 has a bottom plate portion 26, a peripheral wall portion 27, and an outer peripheral flange 28. The peripheral wall portion 27 has an annular planar shape, and its lower end is connected to the outer peripheral edge of the bottom plate portion 26. The outer peripheral flange 28 has an annular planar shape, and its inner peripheral edge is connected to the upper end of the peripheral wall portion 27.

[0041] The upper case 35 is a hollow body with an opening 36 formed on its lower surface. The upper case 35 has a top plate portion 37, a peripheral wall portion 38, and an outer peripheral flange 39. The peripheral wall portion 38 has an annular planar shape, and its upper end is connected to the outer peripheral edge of the top plate portion 37. The outer peripheral flange 39 has an annular planar shape, and its inner peripheral edge is connected to the lower end of the peripheral wall portion 38.

[0042] As shown in Figure 2, battery modules 40 and 60 are provided inside the lower case 24. Battery modules 40 and 60 are arranged in the front-to-back direction. More specifically, battery module 60 is located behind battery module 40. Battery modules 40 and 60 are electrically connected to each other.

[0043] As shown in Figures 1 and 2, the battery module 40 is a substantially rectangular parallelepiped-shaped member with its longitudinal direction in the vehicle's front-rear direction. As shown in Figures 3 and 4, the module case 42 that constitutes the outer shape of the battery module 40 is made of an aluminum alloy. The module case 42 comprises a case body 43 and a lid 45.

[0044] The case body 43 comprises a U-shaped body section 44B, a front panel section 44F, and a rear panel section 44R, with the top and front and rear surfaces open. The front panel section 44F is fixed to the front end surface of the body section 44B, and the rear panel section 44R is fixed to the rear end surface of the body section 44B.

[0045] Each laminated battery cell 48 comprises a positive electrode sheet, a negative electrode sheet, a separator, and a laminate film 49. As shown in Figure 4, the laminate film 49 has a left component and a right component. By welding the outer edges of the left and right components together, a bag-like member is formed, and this bag-like member covers the laminate having the positive electrode sheet, negative electrode sheet, and separator. A portion of the positive electrode terminal 48P and a portion of the negative electrode terminal 48N (see Figure 4) of the laminate are located outside the laminate film 49. The positive electrode terminal 48P and negative electrode terminal 48N of each battery cell 48 are joined to a busbar (not shown) by laser welding.

[0046] In this configuration, a smoke-venting section 51 is formed at the upper edge of the battery cell 48 by welding the upper edge of the left component and the upper edge of the right component of the laminate film 49 together. The smoke-venting section 51 is normally closed. That is, the bag-shaped member made of the laminate film 49 normally seals the positive electrode sheet, negative electrode sheet, separator and electrolyte. However, for example, when an internal short circuit occurs in the battery cell 48 and the internal pressure of the battery cell 48 reaches a predetermined value, the smoke-venting section 51 opens, and gases and other substances inside the battery cell 48 are discharged to the outside of the battery cell 48 through the smoke-venting section 51.

[0047] Multiple battery cells 48 arranged in a left-right direction are housed in the internal space of the case body 43. As shown in Figure 3, a lid 45 is placed over the top surface of the case body 43, which houses the multiple battery cells 48 and busbars, and the outer edge of the lid 45 is fixed to the upper end of the case body 43. As shown in Figures 3 and 4, multiple first exhaust holes 46, which are elongated holes, are formed in the lid 45.

[0048] Although detailed drawings and explanations are omitted, the battery module 60 has the same structure as the battery module 40. As shown in Figure 2, the battery modules 40 and 60 are placed on the bottom plate portion 26 of the lower case 24. Furthermore, the battery modules 40 and 60 are fixed to the bottom plate portion 26 by fixing means. These fixing means are, for example, bolts that pass through through holes provided in fixed portions (not shown) protruding from the outer surface of the case body 43 and are screwed into female threaded holes (not shown) provided in the bottom plate portion 26.

[0049] Furthermore, the battery pack 20 comprises a lower case 24, a battery module 40, and a cover unit 63 that is attached to the battery module 60. The cover unit 63 includes a heat-resistant insulating member (fixing body) 65 and a fixing bracket 80.

[0050] As shown in Figure 5, the heat-resistant insulating member 65 has a main member 66 and an auxiliary member (second plate-shaped part) 75. Both the main member 66 and the auxiliary member 75 are plate-shaped members made of mica. As is well known, mica has excellent electrical insulation and heat resistance. Furthermore, mica has low thermal conductivity.

[0051] The main body member 66 has a base portion 67 with a substantially rectangular planar shape, a pair of flanges 69 projecting downward from both side edges of the base portion 67, a fixing projection 70 projecting forward from the front edge of the base portion 67, and a connecting plate-like portion (first plate-like portion) 71 projecting rearward from the rear edge of the base portion 67. The planar shape of the base portion 67 is substantially the same as that of the case body 43 and the lid 45. Furthermore, a plurality of second smoke exhaust holes 68 are formed in the base portion 67. As shown in Figures 5 and 6, the connecting plate-like portion 71 has an inclined portion 72 extending diagonally upward from the base portion 67, and a first clamping portion 73 extending rearward from the rear end of the inclined portion 72. The left-right dimension of the connecting plate-like portion 71 is smaller than that of the base portion 67. The connecting plate-like portion 71 is elastically deformable in the vertical direction, which is the thickness direction of the plate.

[0052] The auxiliary member 75 has a fixed portion 76, an inclined portion 77 extending diagonally upward from the rear edge of the fixed portion 76, and a second clamping portion 78 extending rearward from the rear end of the inclined portion 77. The left-right dimensions of the auxiliary member 75 are larger than those of the connecting plate-like portion 71 and are approximately the same as those of the base portion 67. The auxiliary member 75 is elastically deformable in the vertical direction, which is the thickness direction of the plate.

[0053] As shown in Figure 6, the fixed portion 76 of the auxiliary member 75 is brought into contact with the lower surface of the rear end of the base 67. Furthermore, multiple bolts 87 are inserted from above into multiple through holes 67A formed in the rear end of the base 67 and multiple through holes 76A formed in the fixed portion 76, and the lower part of each bolt 87 is screwed into a weld nut 76B (see Figure 6) fixed to the lower surface of the fixed portion 76. In other words, the fixed portion 76 is fixed to the lower surface of the rear end of the base 67 using multiple bolts 87 and weld nuts 76B. When the fixed portion 76 is fixed to the base 67 in this way, a gap is formed between the inclined portion 72 and the inclined portion 77, and further, an insertion groove 79, which is a gap, is formed between the first clamping portion 73 and the second clamping portion 78. Here, the vertical distance between the lower surface of the first clamping portion 73 and the upper surface of the second clamping portion 78 when the connecting plate-shaped portion 71 and the auxiliary member 75 are in a free state is defined as H1. In other words, when the connecting plate-shaped portion 71 and the auxiliary member 75 are in a free state, the vertical dimension of the insertion groove 79 is H1.

[0054] As shown in Figure 5, the fixing bracket 80, which is a metal plate-shaped member, has a first fixed portion 81, an inclined portion 82 extending diagonally downward from the front end of the first fixed portion 81, and a second fixed portion 83 extending forward from the front end of the inclined portion 82. Multiple through holes 81A are formed in the first fixed portion 81, and one through hole 83A is formed in the second fixed portion 83.

[0055] As shown in Figure 3, the first fixed portion 81 of the fixing bracket 80 is placed on the upper surface of the fixing projection 70 of the main body member 66. Furthermore, multiple bolts 88 are inserted from above into each through hole 81A of the first fixed portion 81 and into multiple through holes 70A formed in the fixing projection 70, and the lower part of each bolt 88 is screwed into a weld nut (not shown) fixed to the lower surface of the fixing projection 70. In other words, the first fixed portion 81 is fixed to the upper surface of the fixing projection 70 using multiple bolts 88 and weld nuts.

[0056] Two main body members 66, integrated with the auxiliary member 75 and the fixing bracket 80, are mounted on the top of the battery module 40 and the battery module 60, respectively. That is, as shown in Figure 2, each base 67 is placed over the top surface of the corresponding module case 42 (lid 45), and the left and right flanges 69 contact the upper edges of both sides of the module case 42. This "contact" means that the left and right flanges 69 contact both sides of the module case 42 simultaneously, or that when one flange 69 contacts one side of the module case 42, the other flange 69 faces the other side of the module case 42 while forming a small gap. As shown in Figure 2, the fixing bracket 80 is connected to the front of the base 67 mounted on the battery module 40, and the fixing bracket 80 is connected to the rear of the base 67 mounted on the battery module 60. Furthermore, an auxiliary member 75 connected to the rear of the base 67 attached to the battery module 40 and an auxiliary member 75 connected to the front of the base 67 attached to the battery module 60 face each other in the front-rear direction. In addition, the second fixed portion 83 of the fixing bracket 80 attached to the base 67 attached to the battery module 40 and the second fixed portion 83 of the fixing bracket 80 attached to the base 67 attached to the battery module 60 contact the upper surface of the bottom plate portion 26 of the lower case 24. Furthermore, bolts 89 that pass through the through holes 83A formed in the second fixed portion 83 of each fixing bracket 80 are screwed into female screw holes 26A formed in the bottom plate portion 26 (see Figure 5. The illustration of the female screw holes for fixing the battery module 60 is omitted). In other words, each fixing bracket 80 is fixed to the bottom plate portion 26 using the bolts 89.

[0057] Furthermore, as shown in Figures 2 and 6, a metal plate fixing member 85 is inserted into the insertion groove 79 formed between the first clamping portion 73 and the second clamping portion 78 on the battery module 40 side, and into the insertion groove 79 formed between the first clamping portion 73 and the second clamping portion 78 on the battery module 60 side. Here, the plate thickness (vertical dimension) of the fixing member 85 is H2. Furthermore, the plate thickness H2 of the fixing member 85 is greater than the vertical dimension H1 of the insertion groove 79 when the connecting plate-shaped portion 71 and the auxiliary member 75 are in a free state.

[0058] For example, the fixing member 85 is inserted into the insertion groove 79 on the battery module 40 side and the insertion groove 79 on the battery module 60 side from the left opening of the insertion groove 79 on the battery module 40 side and the left opening of the insertion groove 79 on the battery module 60 side. As described above, the plate thickness H2 of the fixing member 85 is greater than the vertical dimension H1 of the insertion groove 79 when the connecting plate-shaped part 71 and the auxiliary member 75 are in a free state. Therefore, the connecting plate-shaped part 71 and the auxiliary member 75 are elastically deformed by the fixing member 85, and the first clamping part 73 of the connecting plate-shaped part 71 and the second clamping part 78 of the auxiliary member 75 are pressed against the upper and lower surfaces of the fixing member 85, respectively. That is, the fixing member 85 is fitted into the connecting part 74 which has a connecting plate-shaped part 71 having a first clamping part 73 and an auxiliary member 75 having a second clamping part 78.

[0059] When the heat-resistant insulating members 65 are attached to the battery modules 40 and 60 in this manner, the first smoke exhaust holes 46 of each cover 45 and the second smoke exhaust holes 68 of each main body member 66 face each other in the vertical direction.

[0060] A sealing material (not shown) is provided over the entire upper surface of the outer flange 28 of the lower case 24, which houses the battery modules 40 and 60, and the outer flange 39 of the upper case 35 rests on the upper surface of the outer flange 28 and the sealing material. Furthermore, multiple points on the outer flange 28 and outer flange 39 are fixed together by multiple fixing members. This completes the battery pack 20.

[0061] In this configuration, the battery case 22 of the battery pack 20 is supported by the rockers 12 and the cross members 14. That is, as shown in Figures 1 and 2, with the top plate portion 37 and peripheral wall portion 38 of the upper case 35 located in the space enclosed by the rockers 12 and the cross members 14, the outer peripheral flange 39 is brought into contact with the lower surface of each rocker 12 and each cross member 14 from below. Furthermore, the lower surface of the rockers 12 and multiple points on the outer peripheral flanges 28 and 39 are fixed together by multiple fixing members.

[0062] (Mechanism of action and effect) Next, the operation and effects of the embodiment will be described.

[0063] For example, if an internal short circuit occurs in either one of the battery cells 48 of battery module 40 or battery module 60, the internal pressure of this battery cell 48 will rise. When the internal pressure of this battery cell 48 reaches a predetermined value, the smoke exhaust portion 51 of the laminate film 49 opens. That is, the upper edge of the left component and the upper edge of the right component of the laminate film 49 separate. As a result, the high-temperature debris inside the battery cell 48 is discharged upward to the heat-resistant insulating member 65 through the first smoke exhaust hole 46 of the lid 45 and the second smoke exhaust hole 68 of the main body member 66. Therefore, the risk of the high-temperature debris filling the module case 42 and causing high heat to other battery cells 48 is small. Consequently, when one of the battery cells 48 of battery module 40 or battery module 60 experiences thermal runaway, the risk of a heat chain occurring among the multiple battery cells 48 contained in the battery modules 40 and 60 having this battery cell 48 is small. Therefore, there is little risk of the battery pack 20 catching fire if one of the battery cells 48 in either the battery module 40 or the battery module 60 experiences thermal runaway. The high-temperature debris includes, for example, the internal electrodes, electrolyte, and gas (smoke) of the battery cell 48.

[0064] Furthermore, if high-temperature debris from any of the battery cells 48 of the battery module 40 is forcefully discharged above the heat-resistant insulating member 65, this debris may adhere to the upper surface of the base 67 of the heat-resistant insulating member 65 of the battery module 60. However, as mentioned above, since the base 67 is made of mica, the base 67 has excellent heat resistance. Therefore, even if high-temperature debris adheres to the upper surface of the base 67, there is little risk of the base 67 being significantly deformed or damaged. As a result, there is little risk of the high heat transmitted from the debris to the base 67 being transmitted to the battery cells 48 located inside the module case 42 of the battery module 60. In other words, there is little risk of a heat chain occurring between the multiple battery cells 48 contained in the battery module 60 due to debris discharged from the battery module 40. Moreover, even if debris comes into contact with the base 67, the heat from the debris is unlikely to be transmitted from the mica base 67, which has low thermal conductivity, to the fixing bracket 80. Therefore, the fixed state between the fixing bracket 80 and the lower case 24 (bottom plate portion 26) is easily maintained.

[0065] Furthermore, since the base 67 has electrical insulating properties, there is little risk of a short circuit occurring between the debris and the battery cells 48 of the battery module 60 via the base 67 when the debris is charged.

[0066] Furthermore, in the battery pack 20, a fixing member 85 is detachably fitted into an insertion groove 79 formed between the connecting plate-shaped portion 71 of the heat-resistant insulating member 65 and the auxiliary member 75, which are attached to the battery modules 40 and 60. In other words, the fixing member 85 is supported by the connecting portion 74 of the two heat-resistant insulating members 65 that are attached to the battery modules 40 and 60, respectively. As described above, each heat-resistant insulating member 65 attached to the battery modules 40 and 60 is fixed to the lower case 24 via bolts 89. Then, each heat-resistant insulating member 65 fixed to the lower case 24 in this manner is mechanically connected to each other by the fixing member 85. Therefore, the heat-resistant insulating member 65 can be easily and securely attached to each battery module 40 and 60. Accordingly, even if, for example, debris forcefully ejected upward from one battery cell 48 of the battery module 40 collides with the base 67, there is little risk of the main body member 66 falling off the module case 42 or the auxiliary member 75 falling off the main body member 66.

[0067] Furthermore, if the heat-resistant insulating member 65 (main body member 66) is attached to the battery modules 40 and 60 by double-sided tape, the heat inside the battery case 22 may cause the adhesive strength of the double-sided tape to disappear, potentially causing the heat-resistant insulating member 65 to detach from the battery modules 40 and 60. In contrast, in this embodiment, the fixing member 85 is mechanically connected to the insertion groove 79 (connecting plate-shaped part 71, auxiliary member 75) of the heat-resistant insulating member 65. Therefore, even when the inside of the battery case 22 becomes hot, there is less risk of each heat-resistant insulating member 65 detaching from the battery modules 40 and 60 compared to the case where the heat-resistant insulating member 65 is attached to the battery modules 40 and 60 using double-sided tape.

[0068] Furthermore, when using double-sided tape, it is necessary to ensure that the adhesive areas of the double-sided tape on the lid 45 and base 67 do not overlap with the first smoke exhaust hole 46 and the second smoke exhaust hole 68 in the vertical direction. In other words, when using double-sided tape, the position and size of the first smoke exhaust hole 46 provided on the lid 45, and the position and size of the base 67 provided on the main body member 66 are constrained by the double-sided tape. In contrast, this problem does not occur in this embodiment.

[0069] Furthermore, while the adhesion of the double-sided tape to the lid 45 and base 67 is performed manually by an operator, the attachment and detachment of the fixing member 85 to the insertion groove 79 can be performed automatically using an attachment / detachment device (not shown).

[0070] Furthermore, when using double-sided tape, the lid 45 and the main body member 66 must be manufactured so that the flatness of the upper surface of the lid 45 and the lower surface of the base 67 is high. In this case, when mica is used as the material for the main body member 66, only a specific type of mica can be selected. For example, in this case, only flexible mica can be selected as the material for the main body member 66. In contrast, when using the connecting plate-shaped part 71, auxiliary member 75 and fixing member 85 as in this embodiment, it is not necessary to increase the flatness of the upper surface of the lid 45 and the lower surface of the base 67. Therefore, when using mica as the material for the main body member 66, various types of mica can be selected.

[0071] Furthermore, as is clear from Figures 1 and 2, in a plan view, the fixing member 85 closes the gap between the connecting plate-shaped part 71 (first clamping part 73) and auxiliary member 75 (second clamping part 78) on the battery module 40 side and the connecting plate-shaped part 71 (first clamping part 73) and auxiliary member 75 (second clamping part 78) on the battery module 60 side. Therefore, the fixing member 85 can prevent high-temperature debris moving from above the battery module 40 or battery module 60 towards this gap from passing through the gap downwards and contacting at least one of the rear end of the battery module 40 and the front end of the battery module 60. Moreover, even if high-temperature debris comes into contact with the fixing member 85, which has high thermal conductivity because it is made of metal, the heat from the fixing member 85 is not easily transferred to the mica-made connecting plate-shaped part 71 and auxiliary member 75, which have low thermal conductivity. Therefore, even if high-temperature debris comes into contact with the fixing member 85, there is little risk that the heat from the fixing member 85 will be transferred to at least one of the battery cells 48 of the battery module 40 and the battery module 60.

[0072] Furthermore, by moving the fixing member 85 relative to the insertion grooves 79 of the battery modules 40 and 60 in the left-right direction, the fixing member 85 can be inserted into each insertion groove 79 or removed from each insertion groove 79. For example, if the left-right dimension of the fixing member 85 is smaller than the left-right distance DS (see Figure 2) between the left side of the auxiliary member 75 of the heat-resistant insulating member 65 attached to the battery modules 40 and 60 and the inner surface of the left side 27L of the peripheral wall portion 27 of the lower case 24, it is possible to insert the fixing member 85 into the insertion groove 79 of each heat-resistant insulating member 65 or move the fixing member 85 to the left from the insertion groove 79, even when the battery modules 40 and 60 are fixed to the bottom plate portion 26.

[0073] Furthermore, the connecting portion 74 having an insertion groove 79 is composed of a connecting plate-shaped portion 71 and an auxiliary member 75 that are elastically deformable in the vertical direction. Therefore, in this embodiment, the connecting portion 74 having an insertion groove 79 is realized with a simple structure.

[0074] Furthermore, when the connecting plate-shaped portion 71 and the auxiliary member 75 are in a free state, the vertical distance between the lower surface of the first clamping portion 73 and the upper surface of the second clamping portion 78 is H1, and the plate thickness (vertical dimension) of the fixing member 85, which is a metal plate, is H2, which is greater than H1. Therefore, when the fixing member 85 is inserted into the insertion groove 79 formed between the first clamping portion 73 and the second clamping portion 78, the first clamping portion 73 and the second clamping portion 78 elastically deform vertically and press against the upper and lower surfaces of the fixing member 85, respectively. As a result, the connecting portion 74 and the fixing member 85 can be mechanically joined easily and reliably.

[0075] Furthermore, the left and right flanges 69 of the main body member 66 of the heat-resistant insulating member 65 contact the upper left and right sides of the corresponding module case 42. Therefore, even if the vehicle 10 vibrates or debris ejected forcefully by the battery cell 48 collides with the main body member 66, there is little risk of the main body member 66 moving relative to the corresponding module case 42 in the left-right direction.

[0076] Furthermore, since the connecting plate-shaped part 71 and the auxiliary member 75 are made of mica, the heat-resistant connecting part 74 to which the fixing member 85 is connected can be manufactured at low cost.

[0077] Furthermore, the front and rear of the metal fixing member 85 are covered from above and below by the mica-made connecting plate portion 71 and auxiliary member 75. Therefore, the connecting plate portion 71 and auxiliary member 75 can suppress the fixing member 85 from becoming hot due to the heat of the high-temperature debris discharged from the battery cell 48.

[0078] Although battery devices according to each embodiment have been described above, these can be modified as appropriate without departing from the spirit of the present invention.

[0079] For example, the main body member 66 and the auxiliary member 75 may be made of materials other than mica. For example, at least one of the main body member 66 and the auxiliary member 75 may be made of at least one of glass, silica (a substance containing silicon as a constituent element), and alumina (aluminum oxide).

[0080] A portion of the fixing member 85 may be fixed to the battery module. For example, the fixing member 85 may be fixed to the case body 43 of the module case 42 of the battery module 60. In this way, the heat-resistant insulating member 65 can be attached to each of two adjacent battery modules 40 and 60 more easily.

[0081] The number of battery modules housed in the battery case 22 may be one or more, including three or more. Furthermore, the arrangement of the battery modules may differ from the front-to-back direction.

[0082] As shown in Figure 7, for example, the battery pack 20 may consist of only one battery module 40, with the rear part of the fixing member 85 fixed to the rear plate portion 27B of the peripheral wall portion 27 of the lower case (fixing body) 24, and the front part of the fixing member 85 fitted into the insertion groove 79 of the heat-resistant insulating member 65 attached to the battery module 40. Alternatively, the battery pack 20 may consist of multiple battery modules, with the fixing member 85 fixed to the inner surface of the peripheral wall portion 27 fitted into the insertion groove 79 of the heat-resistant insulating member 65 attached to one of the battery modules facing the inner surface of the peripheral wall portion 27.

[0083] The number, position, and size of the first exhaust holes 46 formed in the cover 45, and the number, position, and size of the second exhaust holes 68 formed in the base 67, may differ from those described above.

[0084] The battery cell 48 may be a battery cell of a different type than the laminated type. Preferably, this battery cell is equipped with a release valve (safety valve) that opens when the internal pressure of the battery cell reaches a predetermined value.

[0085] The vehicle may be an electric vehicle other than an electric vehicle. For example, the vehicle may be a hybrid electric vehicle (HEV) or a plug-in hybrid electric vehicle (PHEV). [Explanation of Symbols]

[0086] 20 Battery pack (battery device) 22 Battery Case 24 Lower case (fixed body) 26 Bottom plate part 40 Battery Modules 42 Module Cases 46 1st smoke exhaust hole 48 battery cells 60 Battery Modules 65 Heat-resistant insulating material (fixed body) 67 Base 68 2nd smoke exhaust hole 69 Flange 71 Connecting plate-shaped part (first plate-shaped part) 74 Connection part 75 Auxiliary member (second plate-shaped part) 79 Insertion groove 80 Fixing bracket 85 Fixing member

Claims

1. A battery module having a plurality of battery cells arranged in a predetermined direction, and a module case that houses the plurality of battery cells, A heat-resistant insulating member is attached to the battery module so as to cover the first smoke exhaust hole formed in the module case, and has a connection portion with an insertion groove. A fixing member that is detachably fitted into the aforementioned insertion groove and supported by a fixing body, A battery device equipped with the following features.

2. When the direction along a predetermined straight line is defined as the first direction, The battery device according to claim 1, wherein one end of the insertion groove in the first direction is open.

3. When the direction perpendicular to the first direction is defined as the second direction, The battery device according to claim 2, wherein both ends of the insertion groove in the second direction are open.

4. When the direction perpendicular to the first and second directions is defined as the third direction, The aforementioned connection part, The first plate-like portion and The first plate-shaped portion and the second plate-shaped portion facing the third direction are arranged so as to form the insertion groove between them, The battery device according to claim 3, comprising:

5. The first plate-like portion and the second plate-like portion are elastically deformable in the third direction, The battery device according to claim 4, wherein the dimension of the gap between the first plate-shaped portion and the second plate-shaped portion in the third direction when the first plate-shaped portion and the second plate-shaped portion are in a free state is smaller than the dimension of the fixing member in the third direction.

6. The heat-resistant insulating member is From above, the base facing the first smoke exhaust port, A pair of flanges that are separated from each other in the vertical direction and in a second direction perpendicular to the first direction, Equipped with, The battery device according to claim 3, wherein the upper part of the module case is located between a pair of flanges, and the pair of flanges are in contact with the upper part of the module case.

7. The connecting portion is provided at one end of the base in the first direction. The battery device according to claim 6, wherein a fixing bracket is fixed to the bottom plate portion of the battery case housing the battery module, the heat-resistant insulating member, and the fixing member, and to the other end of the base portion in the first direction.

8. The battery device according to any one of claims 1 to 3, wherein the connection portion is made of mica.

9. The battery device according to any one of claims 1 to 3, wherein a second smoke exhaust hole facing the first smoke exhaust hole is formed in the heat-resistant insulating member.

10. The battery device according to any one of claims 1 to 3, wherein the fixing member is made of metal.

11. The battery comprises multiple such modules, The battery device according to any one of claims 1 to 3, wherein the connection portion of the heat-resistant insulating member attached to at least one of the battery modules is the fixed body.

12. The battery device according to any one of claims 1 to 3, wherein the fixing member is fixed to the battery module to which the heat-resistant insulating member having the connection portion which is the fixing body is attached.

13. The battery device according to any one of claims 1 to 3, wherein the battery case housing the battery module, the heat-resistant insulating member, and the fixing member is the fixing body.

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