Battery pack

Abstract

To improve the vertical rigidity of a battery pack and to distribute a load input to the battery pack from below across a floor panel more reliably.SOLUTION: In a battery pack arranged below a floor panel of a vehicle, a housing of the battery pack includes an upper cover member covering a battery module from above, and a lower cover member covering the battery module from below. The upper cover member includes a first opposing part that lies, in a vertical direction, opposite at least one end plate part of a pair of end plate parts, and a second opposing part that lies opposite a cell part in the vertical direction. The lower cover member abuts on the one end plate part from below. In the vertical direction, a first distance between the one end plate part and the first opposing part is smaller than a second distance between the cell part and the second opposing part.SELECTED DRAWING: Figure 3

Description

[Technical Field]

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

[0002] Patent Document 1 below discloses a floor structure for an electric vehicle that has a lower floor that is separated from the upper floor and is located below the upper floor. The upper floor has side members and side sills on the outside of the upper floor, the lower floor has a battery mounting area formed by members arranged in a grid pattern, a frame is provided around the mounting area that is detachably attached to the side members of the upper floor, and an extension frame is provided at approximately the center of the frame in the front-to-rear direction, extending outward and detachably attached near the center pillar mounting area of ​​the side sill. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 2936959 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the case of a battery pack, even if the rigidity of the battery pack in the vertical direction is improved, there is a risk that the load input from below to the lower cover member of the battery pack may not be sufficiently distributed to the upper cover member or floor panel.

[0005] An object of the present invention is to improve the vertical rigidity of a battery pack and to more reliably distribute a load input to the battery pack from below to a floor panel. [Means for solving the problem]

[0006] A battery pack according to one aspect of the present invention is disposed below a floor panel of a vehicle, and the battery pack housing includes an upper cover member that covers the battery modules from above and a lower cover member that covers the battery modules from below. The upper cover member includes a first opposing portion that faces vertically at least one of a pair of end plate portions, and a second opposing portion that faces vertically the cell portion. The lower cover member abuts the one end plate portion from below. In the vertical direction, a first distance between the one end plate portion and the first opposing portion is smaller than a second distance between the cell portion and the second opposing portion. [Effects of the Invention]

[0007] According to the present invention, the rigidity of the battery pack in the vertical direction can be improved, and a load input to the battery pack from below can be more reliably distributed to the floor panel. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is a partial perspective view showing the arrangement relationship between the battery pack and a floor panel according to the embodiment. [Figure 2] FIG. 1 is a perspective view of a battery pack according to an embodiment. [Figure 3] FIG. 2 is a diagram for explaining the battery pack according to the embodiment, and is a partial perspective view showing the arrangement relationship between the lower cover member and the battery module. [Figure 4] FIG. 10 is a diagram for explaining the battery pack according to the embodiment, and is a partial plan view showing the arrangement relationship between the lower cover member and the battery module. [Figure 5] FIG. 2 is a perspective view illustrating a battery module housed in a housing of the battery pack according to the embodiment. [Figure 6] 10 is a diagram for explaining the battery pack according to the embodiment, and is a partial cross-sectional view taken along line AA in FIG. 9, showing the arrangement relationship between the floor panel, the upper cover member, the lower cover member, and the battery module. [Figure 7]10 is a diagram for explaining the battery pack according to the embodiment, and is a partial cross-sectional view taken along line BB in FIG. 9, showing the arrangement of the upper cover member, the lower cover member, and the battery module. [Figure 8] 10 is a diagram for explaining the battery pack according to the embodiment, and is a partial cross-sectional view taken along line CC in FIG. 9, showing the arrangement relationship between the upper cover member, the lower cover member, and the battery module. [Figure 9] FIG. 2 is a diagram for explaining a battery pack according to an embodiment, and is a partial plan view showing the arrangement relationship between a floor panel, a lower cover member, and a battery module. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, a battery pack according to an embodiment will be described with reference to the drawings. In each drawing, FR and RR indicate the front and rear in the longitudinal direction of the vehicle, LH and RH indicate the left and right in the width direction of the vehicle, and UP and DN indicate the top and bottom in the vertical direction of the vehicle. The center of the vehicle in the width direction is referred to as the inner side in the vehicle width direction, and the side opposite the inner side in the width direction is referred to as the outer side in the vertical direction of the vehicle. In each drawing, IS indicates the inner side in the width direction of the vehicle, and OS indicates the outer side in the width direction of the vehicle. In the following description, the front and rear in the longitudinal direction of the vehicle, and the top and bottom in the vertical direction of the vehicle will be simply referred to as the "front of the vehicle," "rear of the vehicle," "upper," and "lower," respectively. Elements having the same function will be assigned the same reference numerals, and redundant description will be omitted.

[0010] The battery pack 1 according to the embodiment includes a housing 5 and a battery module 20.

[0011] 1, the battery pack 1 is disposed below a floor panel 40 of a vehicle (not shown). The vehicle is an electric vehicle driven by an electric motor (not shown), and the battery pack 1 is used as a power source for supplying driving power to the vehicle. The battery pack 1 may be fixed to the underside of the vehicle by fastening the peripheral edge of the housing 5 to a vehicle body frame member 50 such as a side sill 51 using fasteners such as bolts (not shown).

[0012] As shown in Fig. 1, floor panel 40 is a plate-like member made of a metal such as iron or steel and having a generally rectangular shape in a plan view, which separates the interior and exterior of the vehicle. A vehicle body frame member 50 is disposed on floor panel 40. This increases the rigidity of floor panel 40 in the longitudinal and vertical directions of the vehicle. This in turn improves the rigidity of the vehicle body in the longitudinal and vertical directions.

[0013] In the illustrated example, the body frame members 50 include side sills 51, cross members 52a and 52b, front side member extensions 53, a front center member 54, and a floor member 55, which are joined to the floor panel 40 using joining means such as welding. Any of these members may be made of metal such as iron or steel.

[0014] The side sills 51 are a pair of left and right members that extend in the front-to-rear direction of the vehicle and are joined to both ends of the floor panel 40 in the vehicle width direction. The cross members 52a, 52b are joined to the upper surface of the floor panel 40 and extend in the vehicle width direction between the pair of side sills 51. The cross members 52a, 52b are elongated members that have a generally hat-shaped cross section that opens downward. In the front-to-rear direction of the vehicle, the cross member 52a is disposed on the front side of the floor panel 40, and the cross member 52b is disposed on the rear side of the cross member 52a.

[0015] The front center member 54 and the front side member extensions 53 are joined to the upper surface of the floor panel 40 and extend in the longitudinal direction of the vehicle on the vehicle front side of the cross member 52a. The front center member 54 is a member having a generally M-shaped cross section that opens downward, and is disposed in the center in the vehicle width direction. The front side member extensions 53 are elongated members having a generally hat-shaped cross section that opens downward, and are disposed as a pair to the left or right of the front center member 54 in the vehicle width direction, spaced a predetermined distance from the front center member 54. The front ends of the front center member 54 and the front side member extensions 53 are joined to a dash panel (not shown), and the rear ends of the front center member 54 are joined to the cross member 52a by joining means such as welding.

[0016] Floor member 55 is a long member having a generally hat-shaped cross section that opens downward and is joined to the upper surface of floor panel 40 between cross member 52a and cross member 52b. Floor members 55 form a pair on the left and right sides in the vehicle width direction, spaced a predetermined distance from the center of floor panel 40, and extend in the front-to-rear direction of the vehicle. The front end of floor member 55 is joined to cross member 52a, and the rear end of floor member 55 is joined to cross member 52b using joining means such as welding.

[0017] As shown in Fig. 2, the battery pack 1 has a housing 5 as an exterior member that houses the battery module 20. The housing 5 has a hollow rectangular box shape, and has a flat shape in which the overall dimension in the vehicle vertical direction is smaller than the dimensions in the vehicle longitudinal direction or width direction. The shape of the housing 5 can be appropriately set depending on the shape and dimensions of the battery pack 1, the installation method in the vehicle, etc. The housing 5 may also house auxiliary devices (not shown), such as a controller, switch, relay, etc., that manage the capacity, voltage, temperature, etc. of the battery module 20.

[0018] As shown in FIGS. 2 to 4 , the housing 5 includes an upper cover member 6 that covers the battery module 20 from above, and a lower cover member 10 that covers the battery module 20 from below. In the example shown in FIG. 2 , the housing 5 includes an upper case 7 as the upper cover member 6, and a lower case 11 as the lower cover member 10. The upper case 7 is a plate-like member having a substantially rectangular shape in a plan view, and is made of a metal such as iron. The lower case 11 is a box-shaped member with an open top and a bottom, having a substantially rectangular shape in a plan view, and is made of a metal such as aluminum. The housing 5 is sealed by fastening the peripheral edges of the upper case 7 and the lower case 11 together with fasteners such as bolts (not shown).

[0019] As shown in Figures 3 and 4, in the area of ​​the bottom 13 of the lower case 11 on the front side of the vehicle, battery modules 20 are stacked in one layer, with two rows in the vehicle width direction and four rows in the vehicle front-to-rear direction, and the upper case 7 covers the battery modules 20 from above.

[0020] In the vehicle rear region of the lower case 11, battery modules 20 are stacked in two rows, one above the other, in two rows in the vehicle width direction and one in the vehicle front-to-rear direction. Of the battery modules 20, an intermediate cover member 15 is disposed between the lower battery module 20a and the upper battery module 20b. The intermediate cover member 15 is a plate-like member having a substantially rectangular shape in a plan view, and is made of a metal such as iron.

[0021] The lower battery module 20a is placed on the bottom 13 of the lower case 11, and the middle cover member 15 covers the lower battery module 20a from above. The upper battery module 20b is placed on the upper surface of the middle cover member 15, and the upper case 7 covers the upper battery module 20b from above. In this way, the middle cover member 15 covers the lower battery module 20a from above and the upper battery module 20b from below. Therefore, the middle cover member 15 serves as both the upper cover member 6 and the lower cover member 10.

[0022] A sealing member (not shown) made of a rubber material or the like may be interposed at the contact portion between the upper cover member 6 and the lower cover member 10. Also, instead of the upper case 7, a floor panel 40 may be fastened to the peripheral edge of the lower case 11 to seal the housing 5. In that case, the floor panel 40 corresponds to the upper cover member 6. Also, in the example shown, the housing 5 houses multiple battery modules 20, but this is not limiting and the housing may house only one battery module 20.

[0023] A plurality of partition walls 12 that separate the interior of the housing 5 may be provided on the bottom 13 of the lower case 11, spaced apart at predetermined intervals in the vehicle longitudinal direction. In the illustrated example, the partition walls 12 are plate-like members that extend in the vehicle width direction and have a substantially rectangular shape when viewed in the vehicle longitudinal direction. A battery module 20 is disposed between each of the plurality of partition walls 12. This prevents the battery modules 20 from coming into contact with each other when an external force is applied to the battery pack 1.

[0024] 2, the region of the upper case 7 on the rear side of the vehicle may be formed to bulge outward toward the top of the vehicle more than the region on the front side of the vehicle, depending on the number of stages of battery modules 20 arranged in the lower case 11. This allows more battery modules to be arranged on the rear side of the vehicle, making the battery pack 1 thinner as a whole, saving space, and ensuring a larger battery capacity.

[0025] 5, the battery module 20 includes a cell section 21 made up of a plurality of battery cells (not shown), and a pair of end plate sections 22 that sandwich the cell section 21. In the illustrated example, the left side of the battery module 20 in the vehicle width direction corresponds to the outer side in the vehicle width direction, and the right side in the vehicle width direction corresponds to the inner side in the vehicle width direction.

[0026] The battery cells have a flat shape with a widthwise dimension shorter than the longitudinal dimension of the vehicle. The battery cells are configured by, for example, stacking a positive electrode plate and a negative electrode plate with a separator between them, and sealing the stacked power generating element together with an electrolyte in an exterior member such as an aluminum can. The cell section 21 is configured by stacking a plurality of battery cells in a predetermined direction and electrically connecting them to each other via a busbar unit (not shown). In some embodiments, the battery cells may be lithium-ion secondary batteries.

[0027] The pair of end plate portions 22 includes an end plate portion 22a on one side disposed on the outer side of the battery module 20 in the vehicle width direction, and an end plate portion 22b on the other side disposed on the inner side of the battery module 20 in the vehicle width direction. Each of the pair of end plate portions 22 is a plate-like member having a substantially rectangular shape when viewed in the vehicle width direction, and is made of a metal such as aluminum. Note that the end plate portion 22a on one side may be disposed on the inner side of the battery module 20 in the vehicle width direction, and the end plate portion 22b on the other side may be disposed on the outer side of the battery module 20 in the vehicle width direction.

[0028] A plurality of through holes 23 that penetrate in the up-down direction are formed in each of the pair of end plate portions 22. In the illustrated example, the through holes 23 have a substantially triangular cross-sectional shape in plan view. This reduces the weight of the end plate portion 22, and the ribs 24 that separate the through holes 23 ensure the rigidity of the end plate portion 22 in the up-down direction.

[0029] As illustrated in the figure, the battery module 20 may include a pair of end plate portions 22 and an outer peripheral member 27 that covers the horizontal side surfaces of the cell portion 21. The outer peripheral member 27 is a frame member made of a metal such as aluminum and has a substantially rectangular shape in a plan view. The pair of end plate portions 22 and the cell portion 21 may be integrally held by covering each of the pair of end plate portions 22 with the outer peripheral member 27 so that the pair of end plate portions 22 is pressed against the cell portion 21 with a predetermined pressure. In addition, the cell portion 21 may be protected from external forces by providing a protective plate 28 made of, for example, aluminum on the upper or lower side of the battery module 20.

[0030] When constructing the battery module 20, for example, a pair of end plate portions 22 are brought into contact with one side and the other side of the cell portion 21 in the stacking direction of the battery cells while applying a predetermined pressure, so that the cell portion 21 is sandwiched between the pair of end plate portions 22. Then, an outer peripheral member 27 is provided so as to cover the pair of end plate portions 22 and the horizontal side surfaces of the cell portion 21. The outer peripheral member 27 may be joined to the pair of end plate portions 22 by a joining means such as welding.

[0031] The battery module 20 has a connector portion 29 including terminals electrically connected to the internal battery cells. In the illustrated battery module 20, the connector portion 29 is disposed at the upper end portion of the other end plate portion 22b. The connector portions 29 of the multiple battery modules 20 can be electrically connected to each other via a bus bar unit (not shown), or the connector portion 29 can be electrically connected to an electrical component disposed inside the housing 5 via a bus bar unit (not shown).

[0032] 5 to 8, the end plate portion 22a on one side may include an additional portion 25 on the upper side. The additional portion 25 is a member made of a metal such as aluminum that extends in the vehicle front-rear direction above the end plate portion 22a on one side. For this reason, the vertical dimension of the end plate portion 22a on one side is set larger than the vertical dimension of the end plate portion 22b on the other side. Note that the end plate portion 22b on the other side may also include the additional portion 25.

[0033] The additional portion 25 illustrated in the figures has a substantially rectangular or Z-shaped cross section perpendicular to the vehicle longitudinal direction, but is not limited thereto. The cross-sectional shape of the additional portion 25 can be appropriately set depending on the shape, dimensions, or installation method of the battery pack 1 or the battery module 20. By including such an additional portion 25 and appropriately setting the vertical dimension of the additional portion 25, the vertical dimension of each of the pair of end plate portions 22 can be easily changed.

[0034] 6 and 7, one end plate portion 22a may include an elastic portion 26 on its upper side. In the illustrated example, one end plate portion 22a includes an additional portion 25 disposed on its upper side and an elastic portion 26 disposed above the additional portion 25. The elastic portion 26 may be made of, for example, foamed polyurethane. The other end plate portion 22b may also include an elastic portion 26 on its upper side. By including such an elastic portion 26, for example, when a thrust load (described later) is input to the battery pack 1 and one end plate portion 22a is pressed against the upper cover member 6 from below, the load can be absorbed by the elastic portion 26.

[0035] The additional portion 25 or the elastic portion 26 constitutes an upper end portion 30 of the one end plate portion 22a, which faces the upper cover member 6 in the vertical direction. The upper end portion of the additional portion 25 or the elastic portion 26 is located at a position higher than the upper surface of the cell portion 21 of the battery module 20 that includes the additional portion 25 or the elastic portion 26. In other words, the one end plate portion 22a extends above the upper surface of the cell portion 21. As illustrated in FIG. 3, the upper end portion 30 of the one end plate portion 22a and the upper end portion of the partition wall portion 12 are located at approximately the same height in the vertical direction.

[0036] With the battery module 20 disposed on the lower cover member 10, the lower cover member 10 abuts against at least one end plate portion 22a from below. In the example shown in FIGS. 5 to 8, the lower case 11 or the middle cover member 15 serving as the lower cover member 10 has a pedestal portion 14 that protrudes upward from the bottom surface. The pedestal portion 14 abuts against the lower end portion of each of the pair of end plate portions 22. This improves the rigidity of the lower cover member 10 in the vertical direction, and ultimately improves the rigidity of the battery pack 1 in the vertical direction.

[0037] In the illustrated example, a member made of, for example, aluminum is disposed on the lower cover member 10 to form the base portion 14. As shown in Fig. 5, each of the pair of end plate portions 22 is fastened and fixed to the base portion 14 via a fastening member such as a bolt. Note that the base portion 14 may be formed by molding a portion of the lower cover member 10 so that it extends upward.

[0038] Additionally, the additional portion 25 is fastened together with the end plate portion 22a on one side to the base portion 14 of the lower cover member 10 via fasteners such as bolts. The additional portion 25 and the end plate portion 22a on one side may be joined by a joining means such as welding.

[0039] As described above, the upper cover member 6 covers the battery module 20 from above. Therefore, as shown in Figures 6 to 8, the upper case 7 as the upper cover member 6 or the middle cover member 15 includes a first opposing portion 6a that faces vertically at least one end plate portion 22a of the pair of end plate portions 22, and a second opposing portion 6b that faces vertically the cell portion 21.

[0040] The upper cover member 6 illustrated in the drawings has a substantially flat cross section when viewed in the vehicle longitudinal direction, but is not limited to this. For example, the upper cover member 6 may further include a downwardly extending member in a portion thereof, or may have a portion thereof bulging downward, thereby forming a downwardly extending portion. Furthermore, the first opposing portion 6a or the second opposing portion 6b may be the downwardly extending portion.

[0041] In the battery pack 1 according to the embodiment, in the vertical direction, a first distance D1 between one end plate portion 22a of the battery module 20 and the first opposing portion 6a of the upper cover member 6 is smaller than a second distance D2 between the cell portion 21 of the battery module 20 and the second opposing portion 6b. That is, the relationship of first distance D1<second distance D2 is satisfied.

[0042] The first distance D1 refers to the minimum distance in the vertical direction between the end plate portion 22a on one side and the first opposing portion 6a of the upper cover member 6. The second distance D2 refers to the minimum distance in the vertical direction between the cell portion 21 and the second opposing portion 6b of the upper cover member 6.

[0043] 3 and 4, the battery modules 20 located in the second to fourth rows from the front of the vehicle on the vehicle front side of the lower case 11 satisfy the above-mentioned size relationship. Of the lower battery modules 20a arranged on the vehicle rear side of the lower case 11, the battery module 20 located in the second row from the rear of the vehicle satisfies the above-mentioned size relationship. Of the upper battery modules 20b arranged on the vehicle rear side of the lower case 11 and on the upper surface of the middle cover member 15, the battery modules 20 located in the first and second rows from the rear of the vehicle satisfy the above-mentioned size relationship.

[0044] 6, the battery module 20 is covered from above by the upper case 7 serving as the upper cover member 6. Therefore, the first distance D1 between the elastic portion 26, which is the upper end portion 30 of the end plate portion 22a on one side of the battery module 20, and the first opposing portion 6a of the upper case 7 is configured to be smaller than the second distance D2 between the cell portion 21 of the battery module 20 and the second opposing portion 6b of the upper case 7. In other words, the above-mentioned magnitude relationship is satisfied.

[0045] In the illustrated example, if the additional portion 25 is considered to constitute the upper end portion 30 of one end plate portion 22a of the battery module 20, the distance between the additional portion 25 and the first opposing portion 6a of the upper case 7 is the first distance D1. Even in such a case, the first distance D1 is configured to be smaller than the second distance D2. In other words, the above-mentioned magnitude relationship is satisfied.

[0046] 7, the lower battery module 20a is covered from above by an intermediate cover member 15 serving as the upper cover member 6. Therefore, the first distance D1 between the elastic portion 26, which is the upper end portion 30 of one end plate portion 22a of the lower battery module 20a, and the first opposing portion 6a of the intermediate cover member 15 is smaller than the second distance D2 between the cell portion 21 of the lower battery module 20a and the second opposing portion 6b of the intermediate cover member 15. In other words, the above-mentioned magnitude relationship is satisfied.

[0047] In the illustrated example, if the additional portion 25 is considered to constitute the upper end portion 30 of one end plate portion 22a of the battery module 20, the distance between the additional portion 25 and the first opposing portion 6a of the middle cover member 15 is the first distance D1. Even in such a case, the first distance D1 is configured to be smaller than the second distance D2. In other words, the above-mentioned magnitude relationship is satisfied.

[0048] Additionally, the upper battery module 20b is covered from above by the upper case 7, which serves as the upper cover member 6. Therefore, the first distance D1 between the additional portion 25, which is the upper end portion 30 of the end plate portion 22a on one side of the upper battery module 20b, and the first opposing portion 6a of the upper case 7 is configured to be smaller than the second distance D2 between the cell portion 21 of the upper battery module 20b and the second opposing portion 6b of the upper case 7. In other words, the above-mentioned magnitude relationship is satisfied.

[0049] 8, the upper battery module 20b is covered from above by the upper case 7 as the upper cover member 6. Therefore, the first distance D1 between the additional portion 25, which is the upper end portion 30 of the end plate portion 22a on one side of the upper battery module 20b, and the first opposing portion 6a of the upper case 7 is smaller than the second distance D2 between the cell portion 21 of the upper battery module 20b and the second opposing portion 6b of the upper case 7. In other words, the above-mentioned magnitude relationship is satisfied.

[0050] The upper end portion 30 of one end plate portion 22a and the first opposing portion 6a of the upper cover member 6 may be in contact with each other. That is, the value of the first distance D1 may be zero. The values ​​of the first distance D1 and the second distance D2 are not particularly limited and can be set appropriately depending on, for example, the vertical dimension, shape, or installation method of the battery pack 1 or the battery module 20. In one embodiment, the value of the second distance D2 may be 5 mm to 50 mm.

[0051] As shown in FIG. 9, when the battery pack 1 is disposed below the floor panel 40, at least a portion of the end plate portion 22a on one side overlaps with a vehicle body frame member 50 disposed on the floor panel 40 in a plan view.

[0052] In the illustrated example, a portion of the end plate portion 22a on one side of the battery module 20 that is arranged second from the front of the vehicle overlaps with the cross member 52a, which is a body frame member 50, in a plan view. Also, a portion of the end plate portion 22a on one side of the battery module 20 that is arranged third from the front of the vehicle overlaps with the cross member 52b, which is a body frame member 50, in a plan view.

[0053] The body frame member 50 with which a portion of the end plate portion 22a on one side overlaps in plan view can be set appropriately depending on the shape, dimensions, or installation position of the battery pack 1 or the body frame member 50. For example, at least a portion of the end plate portion 22a on one side may overlap with a side sill 51, a front side member extension 53, a front center member 54, or a floor member 55 in plan view.

[0054] The following describes the effects of the battery pack 1 according to the embodiment.

[0055] (1) A battery pack 1 according to an embodiment is a battery pack 1 disposed below a floor panel 40 of a vehicle, and includes a battery module 20 including a cell section 21 consisting of a plurality of battery cells and a pair of end plate sections 22 that sandwich the cell section 21, and a housing 5 that houses the battery module 20. The housing 5 includes an upper cover member 6 that covers the battery module 20 from above, and a lower cover member 10 that covers the battery module 20 from below. The upper cover member 6 includes a first opposing portion 6a that faces vertically at least one end plate section 22a of the pair of end plate sections 22, and a second opposing portion 6b that faces vertically the cell section 21. The lower cover member 10 abuts the one end plate section 22a from below, and a first distance D1 between the one end plate section 22a and the first opposing portion 6a in the vertical direction is smaller than a second distance D2 between the cell section 21 and the second opposing portion 6b.

[0056] For example, when a vehicle goes over a bump or the like while traveling, a thrust load, which is a load input from below, is input to the battery pack 1. Here, according to the battery pack 1 according to the embodiment, a load path, which is a path for transmitting the load input to the lower cover member 10 from below upward, is formed via at least one end plate portion 22a.

[0057] 6, a load path is formed as indicated by arrow D. Therefore, the load is transmitted from lower case 11, which is lower cover member 10, via end plate portion 22a on one side to upper case 7, which is upper cover member 6, and then dispersed to floor panel 40.

[0058] 7, a load path is formed as indicated by arrow E. Therefore, the load is transmitted from lower case 11, which is lower cover member 10, to middle cover member 15 via end plate portion 22a on one side, and then transmitted to upper case 7, which is upper cover member 6, via end plate portion 22a on one side, and is then dispersed to floor panel 40.

[0059] 8, a load path is formed as indicated by arrow F. Therefore, the load is transmitted from middle cover member 15, which serves as lower cover member 10, to upper case 7, which serves as upper cover member 6, via end plate portion 22a on one side, and then dispersed to floor panel 40.

[0060] In this way, the upward thrust load input to the battery pack 1 is transmitted from the lower cover member 10 to the upper cover member 6 via the end plate portion 22a on one side, and is then distributed to the floor panel 40. As a result, according to the battery pack 1 according to the embodiment, the rigidity of the battery pack 1 in the vertical direction is improved, and the load can be distributed to the floor panel 40 more reliably.

[0061] (2) In the battery pack 1 according to the embodiment, when the battery pack 1 is disposed below the floor panel 40, at least a portion of the end plate portion 22a on one side overlaps, in a plan view, with the body frame member 50 disposed on the floor panel 40.

[0062] In the battery pack 1 according to this embodiment, the end plate portion 22a on one side that constitutes the load path overlaps with the vehicle body frame members 50, such as cross members 52a and 52b, that are arranged on the floor panel 40, in a plan view. Therefore, when a thrust load is input to the battery pack 1, the load is transmitted to the highly rigid vehicle body frame member 50 via the end plate portion 22a on one side. Therefore, the load can be distributed to the floor panel 40 more reliably.

[0063] Although the above embodiment has been described taking an electric vehicle as an example, it goes without saying that the battery pack 1 according to the embodiment can also be applied to a battery pack that supplies driving power for a hybrid vehicle. [Explanation of symbols]

[0064] 1 battery pack 5. Cabinet 6 Upper cover member 6a 1st opposing part 6b 2nd opposing part 10 Lower cover member 20, 20a, 20b Battery modules 21 Cell section 22 End plate part 22a End plate part on one side 40 Floor Panel 50 Body frame members D1 First distance D2 2nd distance

Claims

1. A battery pack disposed below a floor panel of a vehicle, a battery module including a cell section made up of a plurality of battery cells and a pair of end plate sections that sandwich the cell section; a housing that houses the battery module; Equipped with the housing includes an upper cover member that covers the battery module from above and a lower cover member that covers the battery module from below, the upper cover member includes a first opposing portion that faces up and down with at least one of the pair of end plate portions, and a second opposing portion that faces up and down with the cell portion, the lower cover member abuts against the one end plate portion from below, The cell section is provided with a plate that covers the plurality of battery cells from above, A battery pack, wherein a first distance between the one end plate portion and the first opposing portion in the vertical direction is smaller than a second distance between the plate and the second opposing portion.

2. 2. The battery pack according to claim 1, wherein, when disposed below the floor panel, at least a portion of the end plate portion on one side overlaps, in a plan view, with a vehicle body frame member disposed on the floor panel.

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