CN220492073U - Battery box and battery pack - Google Patents

Abstract

The utility model belongs to the technical field of battery packs, and particularly relates to a battery box and a battery pack. The battery box body comprises a bottom plate and peripheral side wall plates, at least one side wall plate comprises a lower plate section and an upper plate section connected with the lower plate section, and the lower plate section is arranged close to the bottom plate and gradually contracts into the box body from top to bottom; the upper plate section is vertically arranged, or the upper plate section gradually contracts into the box body from bottom to top, and the projection of the upper end of the upper plate section in the horizontal plane is positioned at the outer side of the projection of the lower end of the lower plate section in the horizontal plane. According to the utility model, the lower plate section of the side wall is gradually contracted into the box body from top to bottom, so that the occupied space of the bottom of the box body in the width direction is effectively reduced; meanwhile, the upper plate section is vertically arranged or gradually contracts into the box body from bottom to top, and the projection of the upper end of the upper plate section in the horizontal plane is positioned at the outer side of the projection of the lower end of the lower plate section in the horizontal plane, so that the size of an opening at the upper end of the battery box body is reduced.

Description

Battery box and battery pack

Technical Field

The utility model belongs to the technical field of battery packs, and particularly relates to a battery box and a battery pack.

Background

With the development of new energy vehicles, sales of new energy vehicles are gradually increased, driving mileage requirements of new energy vehicles are gradually increased, and cost of the whole vehicle is gradually reduced. The battery pack is used as one of the core components of the new energy vehicle, and the size and the cost of the battery pack directly influence the product competitiveness of the whole vehicle. At present, a commercial vehicle battery system is mainly formed by assembling small battery packs in series and parallel, the system assembled by the small battery packs occupies a large space and the number of the battery packs is large, as the main parts of the battery packs, the battery lower box body is mainly formed by adopting a section welding process, for example, the Chinese patent with an authorized bulletin number of CN216288610U and an authorized bulletin day of 2022, 4 and 12 discloses an integrated liquid cooling battery lower box body, wherein a lower flanging (a fixed connecting part) is positioned at the outer side of the side wall of the box body, so that the width of the box body at the lower flanging is the widest part of the box body, the width of the lower flanging part is larger than the width of a sealing surface, the whole battery box body is in a 'soil' shape structure, and the box body structure has the problems of large occupied space of the lower flanging and large whole box body width requirement; meanwhile, the side wall plate of the box body is vertically connected with the bottom plate (liquid cooling plate) or the flanging at the lower part, so that a corresponding stress unloading structure is lacked, and when the box body is subjected to bending stress, the side wall of the box body is easy to break at the root part; and the size of the upper opening of the case is substantially identical to that of the bottom of the case, which also causes difficulty in loading the battery or causes the overall size of the case to be large, thereby reducing the energy density of the battery case.

As an improvement, chinese patent with grant number CN212848623U and grant date 2021, 3 and 30 discloses a battery pack case, a battery pack and a new energy vehicle, where the side wall and the bottom plate of the battery pack case are integrally formed by aluminum casting, and the side wall of the case is inclined relative to the bottom plate, so that the width dimension of the bottom of the case is reduced. However, since the side wall of the case is inclined as a whole, the size of the opening at the upper end of the case is large, which also results in a large size of the case and a large occupied space.

Disclosure of Invention

The utility model aims to provide a battery box body, which solves the problems that the size of an opening at the upper end of the box body is relatively large and the size of the box body is relatively large and the occupied space is relatively large due to the fact that the side wall of the existing battery box body is integrally inclined. The utility model also aims to provide a battery pack which solves the same problems.

In order to achieve the above purpose, the battery box body in the utility model adopts the following technical scheme:

the battery box body comprises a bottom plate and peripheral side wall plates, wherein at least one side wall plate comprises a lower plate section and an upper plate section connected with the lower plate section, and the lower plate section is arranged close to the bottom plate and gradually contracts into the box body from top to bottom; the upper plate section is vertically arranged, or the upper plate section gradually contracts into the box body from bottom to top, and the projection of the upper end of the upper plate section in the horizontal plane is positioned at the outer side of the projection of the lower end of the lower plate section in the horizontal plane.

The beneficial effects of the technical scheme are that: the utility model is improved based on the prior art, and the lower plate section of the side wall gradually contracts into the box body from top to bottom, so that the lower plate section of the side wall deflects inwards compared with the prior art, and the occupied space of the bottom of the box body in the width direction is effectively reduced; meanwhile, the upper plate section is vertically arranged or gradually contracts into the box body from bottom to top, and the projection of the upper end of the upper plate section in the horizontal plane is positioned at the outer side of the projection of the lower end of the lower plate section in the horizontal plane, so that the size of an opening at the upper end of the battery box body is reduced; therefore, the dimension of the whole width direction of the battery box body is ensured to be smaller, the structure of the battery box body is more compact on the premise that the effective dimension of the bottom of the battery box body for accommodating a battery is kept unchanged, and the energy density of the battery box is effectively improved.

Further, the lower plate section is arc-shaped.

The beneficial effects of the technical scheme are that: such setting is curved lower plate section side wall board, effectively reduces box width direction's occupation space, when guaranteeing battery box lateral wall intensity, provides more abundant installation space for the follow-up fixed mounting of battery box.

Further, the side wall plate and the bottom plate are arranged in a split mode, the side wall plate further comprises an inner connecting portion connected with the lower plate section and extending into the box body and an outer connecting portion extending out of the box body, the inner connecting portion is fixedly connected with the bottom plate, and the outer connecting portion forms a fixed connecting portion for fixedly mounting the battery box body.

The beneficial effects of the technical scheme are that: in this arrangement, the side wall plate is provided separately from the bottom plate, and the side wall plate is fixedly connected to the bottom plate via the inner connecting portion, so that the manufacturing process is easier than the case where the side wall plate is provided integrally with the bottom plate.

Further, a crack-stopping groove is formed in the transition position of the lower plate section and the outer connecting portion.

The beneficial effects of the technical scheme are that: by the arrangement, the problem of stress concentration caused by bending of the battery box body is effectively solved.

Further, a lightening hole is formed in the inner connecting portion.

The beneficial effects of the technical scheme are that: the arrangement meets the requirement of light weight of the battery box body while considering the strength of the side wall.

Further, the inner connecting part comprises an outer equal-thickness section which is connected with the outer connecting part and has equal thickness with the outer connecting part, the inner connecting part also comprises an inner equal-thickness section which is connected with the bottom plate and has equal thickness with the bottom plate, and the outer equal-thickness section is flush with the upper surface and connected with the lower surface of the inner equal-thickness section through inclined planes; the weight reducing holes are arranged at the transition part of the outer equal-thickness section and the inner equal-thickness section.

The beneficial effects of the technical scheme are that: in the arrangement, the battery box body is supported on the battery box body bearing component through the outer connecting part, and the arrangement of different thicknesses of the inner connecting part reduces the weight of the battery box body and simultaneously gives attention to strength; the bottom surface of the outer equal-thickness section of the inner connecting part is lower than the bottom surface of the bottom plate of the box body, so that a gap is formed between the bottom surface of the battery box body and the corresponding part of the bearing part of the battery box body, and due to the influence of the heat conductivity of air, the gap can form an air heat insulation layer, so that heat exchange between the battery box body and the corresponding part of the bearing part is avoided, and the cooling medium can effectively dissipate heat of the battery box body; the lightening hole is arranged at the transition part, so that the connection strength requirement of the inner connection part is guaranteed, and the battery box body is lighter.

Further, the inner connecting part is in butt joint with the bottom plate and is welded and fixed, and the upper surface and the lower surface of the butt joint part of the inner connecting part and the bottom plate are respectively flush with the upper surface and the lower surface of the bottom plate.

The beneficial effects of the technical scheme are that: by means of the arrangement, the side wall plate is welded and fixed with the bottom plate through the inner connecting portion, the butt joint portion is flush with the upper surface and the lower surface of the bottom plate, and the tightness of the battery box body is guaranteed while welding is easy.

Further, the inner connecting portion comprises an outer equal-thickness section which is connected with the outer connecting portion and is equal in thickness with the outer connecting portion, the inner connecting portion further comprises an inner equal-thickness section which is connected with the bottom plate and is equal in thickness with the bottom plate, and the outer equal-thickness section is flush with the upper surface and connected with the lower surface of the inner equal-thickness section through inclined plane transition.

The beneficial effects of the technical scheme are that: such setting, the setting of the different thickness of interior connecting portion is effective compromise the intensity demand when reducing battery box weight, makes the outer equal thickness section bottom surface of interior connecting portion be less than the bottom surface of box bottom plate simultaneously to form the space between the bottom surface of battery box and the corresponding part of battery box bearing part, because the heat conductivity influence of air, this space can form the air insulating layer, thereby avoid forming the heat exchange between battery box and the corresponding part of bearing part, make the cooling medium can dispel the heat to the battery box more effectively.

Further, the upper end of the upper plate section is provided with an outwardly extending connecting flange, the projection of the outer edge of the connecting flange in the horizontal plane being located outside or aligned with the projection of the outer edge of the outer connecting portion in the horizontal plane.

The beneficial effects of the technical scheme are that: such setting has reduced the demand of external connection portion at battery box width direction, reduces external connection portion at battery box width direction's occupation space, simultaneously, and the projection of flange outside edge in the horizontal plane is located the outside of the projection of external connection portion's outside edge in the horizontal plane or aligns with it for the upper end opening size of battery box compares prior art and diminishes, thereby makes battery box structure compacter, and then effectively improves the energy density of battery box.

In order to achieve the above purpose, the battery pack of the present utility model adopts the following technical scheme:

the battery pack comprises a battery module and a battery box body, wherein the battery box body comprises a bottom plate and peripheral side wall plates, at least one side wall plate comprises a lower plate section and an upper plate section connected with the lower plate section, and the lower plate section is arranged close to the bottom plate and gradually contracts into the box body from top to bottom; the upper plate section is vertically arranged, or the upper plate section gradually contracts into the box body from bottom to top, and the projection of the upper end of the upper plate section in the horizontal plane is positioned at the outer side of the projection of the lower end of the lower plate section in the horizontal plane.

The beneficial effects of the technical scheme are that: the utility model is improved based on the prior art, and the lower plate section of the side wall gradually contracts into the box body from top to bottom, so that the lower plate section of the side wall deflects inwards compared with the prior art, and the occupied space of the bottom of the box body in the width direction is effectively reduced; meanwhile, the upper plate section is vertically arranged or gradually contracts into the box body from bottom to top, and the projection of the upper end of the upper plate section in the horizontal plane is positioned at the outer side of the projection of the lower end of the lower plate section in the horizontal plane, so that the size of an opening at the upper end of the battery box body is reduced; therefore, the dimension of the whole width direction of the battery box body is ensured to be smaller, the structure of the battery box body is more compact on the premise that the effective dimension of the bottom of the battery box body for accommodating a battery is kept unchanged, and the energy density of the battery box is effectively improved.

Further, the lower plate section is arc-shaped.

The beneficial effects of the technical scheme are that: such setting is curved lower plate section side wall board, effectively reduces box width direction's occupation space, when guaranteeing battery box lateral wall intensity, provides more abundant installation space for the follow-up fixed mounting of battery box.

Further, the side wall plate and the bottom plate are arranged in a split mode, the side wall plate further comprises an inner connecting portion connected with the lower plate section and extending into the box body and an outer connecting portion extending out of the box body, the inner connecting portion is fixedly connected with the bottom plate, and the outer connecting portion forms a fixed connecting portion for fixedly mounting the battery box body.

The beneficial effects of the technical scheme are that: in this arrangement, the side wall plate is provided separately from the bottom plate, and the side wall plate is fixedly connected to the bottom plate via the inner connecting portion, so that the manufacturing process is easier than the case where the side wall plate is provided integrally with the bottom plate.

Further, a crack-stopping groove is formed in the transition position of the lower plate section and the outer connecting portion.

The beneficial effects of the technical scheme are that: by the arrangement, the problem of stress concentration caused by bending of the battery box body is effectively solved.

Further, a lightening hole is formed in the inner connecting portion.

The beneficial effects of the technical scheme are that: the arrangement meets the requirement of light weight of the battery box body while considering the strength of the side wall.

Further, the inner connecting part comprises an outer equal-thickness section which is connected with the outer connecting part and has equal thickness with the outer connecting part, the inner connecting part also comprises an inner equal-thickness section which is connected with the bottom plate and has equal thickness with the bottom plate, and the outer equal-thickness section is flush with the upper surface and connected with the lower surface of the inner equal-thickness section through inclined planes; the weight reducing holes are arranged at the transition part of the outer equal-thickness section and the inner equal-thickness section.

The beneficial effects of the technical scheme are that: in the arrangement, the battery box body is supported on the battery box body bearing component through the outer connecting part, and the arrangement of different thicknesses of the inner connecting part reduces the weight of the battery box body and simultaneously gives attention to strength; the bottom surface of the outer equal-thickness section of the inner connecting part is lower than the bottom surface of the bottom plate of the box body, so that a gap is formed between the bottom surface of the battery box body and the corresponding part of the bearing part of the battery box body, and the gap can form an air heat insulation layer due to the influence of the heat conductivity of air, so that heat exchange between the battery box body and the corresponding part of the bearing part is avoided, and the cooling medium can radiate the battery box body more effectively; the lightening hole is arranged at the transition part, so that the connection strength requirement of the inner connection part is guaranteed, and the battery box body is lighter.

Further, the inner connecting part is in butt joint with the bottom plate and is welded and fixed, and the upper surface and the lower surface of the butt joint part of the inner connecting part and the bottom plate are respectively flush with the upper surface and the lower surface of the bottom plate.

The beneficial effects of the technical scheme are that: by means of the arrangement, the side wall plate is welded and fixed with the bottom plate through the inner connecting portion, the butt joint portion is flush with the upper surface and the lower surface of the bottom plate, and the tightness of the battery box body is guaranteed while welding is easy.

Further, the inner connecting portion comprises an outer equal-thickness section which is connected with the outer connecting portion and is equal in thickness with the outer connecting portion, the inner connecting portion further comprises an inner equal-thickness section which is connected with the bottom plate and is equal in thickness with the bottom plate, and the outer equal-thickness section is flush with the upper surface and connected with the lower surface of the inner equal-thickness section through inclined plane transition.

The beneficial effects of the technical scheme are that: such setting, the setting of the different thickness of interior connecting portion is effective compromise the intensity demand when reducing battery box weight, simultaneously make the outer equal thickness section bottom surface of interior connecting portion be less than with the bottom surface of box bottom plate to form the space between the bottom surface of battery box and the corresponding part of battery box bearing part, because the heat conductivity influence of air, this space can form the air insulating layer, thereby avoid forming the heat exchange between battery box and the corresponding part of bearing part, make the cooling medium can dispel the heat to the battery box more effectively.

Further, the upper end of the upper plate section is provided with an outwardly extending connecting flange, the projection of the outer edge of the connecting flange in the horizontal plane being located outside or aligned with the projection of the outer edge of the outer connecting portion in the horizontal plane.

The beneficial effects of the technical scheme are that: such setting has reduced the demand of external connection portion at battery box width direction, reduces external connection portion at battery box width direction's occupation space, simultaneously, and the projection of flange outside edge in the horizontal plane is located the outside of the projection of external connection portion's outside edge in the horizontal plane or aligns with it for the upper end opening size of battery box compares prior art and diminishes, thereby makes battery box structure compacter, and then effectively improves the energy density of battery box.

Drawings

FIG. 1 is a schematic view of a battery case according to the present utility model;

FIG. 2 is a partial cross-sectional view of FIG. 1;

fig. 3 is a partial view of fig. 2.

In the figure: 100. a battery case; 1. a liquid cooling plate; 2. a side wall panel; 3. a rear wall panel; 4. a cross beam in the middle of the box body; 5. a front wall panel; 6. a water inlet and outlet joint; 7. a module middle cross beam;

21. an outer connection portion; 22. a crack stopper groove; 23. a connecting flange; 24. a lightening hole; 25. an inner connecting part; 26. an upper plate section; 27. a lower plate section;

251. an inner constant thickness section; 252. a transition section; 253. an outer equal thickness section.

Detailed Description

The features and capabilities of the present utility model are described in further detail below in connection with the examples.

Example 1 of battery case in the present utility model:

the battery box body comprises a bottom plate and peripheral side wall plates, wherein at least one side wall plate comprises a lower plate section and an upper plate section connected with the lower plate section, and the lower plate section is arranged close to the bottom plate and gradually contracts into the box body from top to bottom; the upper plate section is vertically arranged, or the upper plate section gradually contracts into the box body from bottom to top, and the projection of the upper end of the upper plate section in the horizontal plane is positioned at the outer side of the projection of the lower end of the lower plate section in the horizontal plane. According to the utility model, the lower plate section of the side wall is gradually contracted into the box body from top to bottom, so that the lower plate section of the side wall is deviated inwards compared with the prior art, and the occupied space of the bottom of the box body in the width direction is effectively reduced; meanwhile, the upper plate section is vertically arranged or gradually contracts into the box body from bottom to top, and the projection of the upper end of the upper plate section in the horizontal plane is positioned at the outer side of the projection of the lower end of the lower plate section in the horizontal plane, so that the size of an opening at the upper end of the battery box body is reduced; therefore, the dimension of the whole width direction of the battery box body is ensured to be smaller, the structure of the battery box body is more compact on the premise that the effective dimension of the bottom of the battery box body for accommodating a battery is kept unchanged, and the energy density of the battery box is effectively improved.

As shown in fig. 1 and 2, the battery case 100 includes a liquid cooling plate 1, a side wall plate 2, a front wall plate 5, and a rear wall plate 3, which are circumferentially enclosed in the liquid cooling plate 1. Specifically, the front wall plate 5 and the rear wall plate 3 are oppositely arranged at the short side edge of the liquid cooling plate 1, the side wall plate 2 comprises a left side wall plate and a right side wall plate which are oppositely arranged at the long side edge of the liquid cooling plate 1, the first ends of the side wall plate 2, the front wall plate 5 and the rear wall plate 3 are enclosed with the liquid cooling plate 1 to form a battery mounting cavity with an upper end opening for mounting a battery module, the adjacent two wall plates are welded by adopting friction stir welding, and each wall plate is welded with the liquid cooling plate 1 by adopting friction stir welding; the second ends of the side wall plate 2, the front wall plate 5 and the rear wall plate 3 are connected to the upper cover of the battery case 100. In this embodiment, the side wall plate 2, the front wall plate 5 and the rear wall plate 3 are extrusion-shaped members, the first ends of the side wall plate 2, the front wall plate 5 and the rear wall plate 3 are ends close to the liquid cooling plate 1 along the direction perpendicular to the liquid cooling plate 1, and the second ends of the side wall plate 2, the front wall plate 5 and the rear wall plate 3 are ends far from the liquid cooling plate 1 along the direction perpendicular to the liquid cooling plate 1. In other embodiments, the side wall plate 2 and the liquid cooling plate 1 may be integrally formed by integral extrusion of a profile.

The cross section of the liquid cooling plate 1 is rectangular, two section plates are welded by friction stir welding, a cooling runner (not shown in the figure) for cooling medium circulation is arranged in the liquid cooling plate 1, a medium inlet and a medium outlet (not shown in the figure) are respectively arranged at the inlet and the outlet of the runner, specifically, liquid inlet holes and liquid outlet holes (not shown in the figure) are formed in symmetrical positions on the left side and the right side of the front wall plate 5 and correspond to the positions of the medium inlet and the medium outlet, the liquid inlet holes and the liquid outlet holes are respectively communicated with a water inlet joint 6, and when the liquid inlet joint 6 respectively penetrates through the liquid inlet holes and the liquid outlet holes and are respectively in sealing connection with the medium inlet and the medium outlet, and the water inlet joint 6 is in sealing connection with the liquid inlet holes and the liquid outlet holes. The cooling medium is introduced into the cooling flow channel from the medium inlet, and flows out of the box body from the medium outlet after exchanging heat with the battery module in the box body, namely, the cooling medium enters from the medium inlet to the medium outlet and flows in a specific direction in the cooling flow channel, so that the cooling heat dissipation performance of the whole box body is ensured. In this embodiment, the liquid cooling plate 1 of the battery box 100 is equivalent to an integrated structure of the original box bottom plate and the liquid cooling plate, and has the functions of the bottom plate and the liquid cooling plate through one component, so that the number of components is reduced, the structure is more compact, the volume and the weight of the battery box cannot be increased, and the energy density of the battery box is ensured. In other embodiments, the liquid cooling plate 1 may be integrally formed by extrusion.

At least one of the side wall plates 2 comprises a lower plate section 27 and an upper plate section 26 connected with the lower plate section 27, wherein the lower plate section 27 is arranged close to the liquid cooling plate 1 and gradually contracts into the box body from top to bottom; the upper plate section 26 is arranged vertically and the projection of the upper end of the upper plate section 26 in the horizontal plane is located outside the projection of the lower end of the lower plate section 27 in the horizontal plane. Specifically, in the present embodiment, the lower plate section 27 is arcuate.

The side wall plate 2 further comprises an inner connecting portion 25 connected with the lower plate section 27 and extending into the box body and an outer connecting portion 21 extending out of the box body, specifically, a first end of the side wall plate 2, namely, the lower end of the side wall plate 2 is provided with the inner connecting portion 25 arranged horizontally and extending into the box body and the outer connecting portion 21 extending out of the box body, the inner connecting portion 25 is fixedly connected with the liquid cooling plate 1, a plurality of outer connecting portions 21 are arranged at intervals along the length direction of the battery box body 100, each outer connecting portion 21 is provided with at least one fixed connecting hole (not labeled in the figure), so that the outer connecting portions 21 form fixed connecting portions for the battery box body 100 to be fixedly mounted, and weight reducing gaps are arranged between the adjacent outer connecting portions 21.

In this embodiment, the outer connecting portion 21 is located at the outer side of the junction between the two ends of the middle cross beam 4 and the middle cross beam 7 of the box body and the side wall plate 2, that is, the outer connecting portion 21 is disposed corresponding to the middle cross beam 4 and the middle cross beam 7 of the box body; the outer connecting part 21 is made of a solid extrusion profile, and a press-riveting fastening screw sleeve or a locking nut at the upper part of a through hole is used for fixedly connecting the battery box body with the frame or the battery mounting bracket; in other embodiments, the outer connecting portion 21 may be formed into a hollow structure by extruding a profile, and the hollow structure may be further welded with a solid aluminum block, and a fastening screw sleeve is press-riveted on the solid aluminum block, a wire screw sleeve is inserted, or a locking nut is inserted in the upper portion of the through hole to form a connecting structure.

In this embodiment, the crack-stopping groove 22 is provided at the transition position of the side wall plate 2 and the outer connecting portion 21, and the side wall plate 2 and the outer connecting portion 21 smoothly transition at the transition position, so as to effectively solve the problem of stress concentration caused by bending of the case body.

The upper end of the upper plate section 26 is provided with a connecting flange 23 extending outwards of the box, the projection of the outer edge of the connecting flange 23 in the horizontal plane being located outside or aligned with the projection of the outer edge of the outer connecting portion 21 in the horizontal plane. Specifically, the second end of the side wall plate 2, that is, the upper end of the side wall plate 2 is formed with a connecting flange 23 disposed in a horizontal direction and extending outside the case body, the connecting flange 23 is provided with an upper cover mounting hole, and at the same time, the projection of the outer edge of the outer connecting portion 21 of the lower plate section 27 in the horizontal plane does not exceed the projection of the outer edge of the connecting flange 23 of the upper plate section 26 in the horizontal plane, so that the cross-sectional size of the battery mounting cavity at the second end is larger than that of the first end; the arc-shaped lower plate section 27 also plays a role in guiding the battery in the process of placing the battery into the battery mounting cavity conveniently.

In this embodiment, the left side wall plate and the right side wall plate each have a lower plate section 27 and an upper plate section 26 connected to the lower plate section 27, the lower plate section 27 is disposed close to the liquid cooling plate 1 and gradually contracts into the box from top to bottom, and the front wall plate 5 and the rear wall plate 3 are disposed vertically with respect to the liquid cooling plate 1. In other embodiments, at least one of the front wall plate 5 and the rear wall plate 3 has a lower plate section and an upper plate section connected to the lower plate section, the lower plate section is disposed near the liquid cooling plate 1 and gradually contracts from top to bottom into the box body; in still other embodiments, at least one side wall plate 2 has a lower plate section disposed adjacent to the liquid cooling plate 1 and gradually shrinking from top to bottom into the tank and an upper plate section connected to the lower plate section, and at least one of the front wall plate 5 and the rear wall plate 3 has a lower plate section disposed adjacent to the liquid cooling plate 1 and gradually shrinking from top to bottom into the tank and an upper plate section connected to the lower plate section. Since the lower plate section 27 of the side wall plate 2 is gradually retracted from top to bottom into the case, the outer connecting portion 21 is offset inward as compared with the prior art, so that the width of the case outer connecting portion 21 is reduced.

In this embodiment, the inner and outer connecting portions 25, 21 are integrally formed with the side wall plate 2.

As shown in fig. 3, the inner connecting portion 25 is butted with the liquid cooling plate 1 and welded and fixed, and the upper and lower surfaces of the butted portion of the inner connecting portion 25 and the liquid cooling plate 1 are respectively flush with the upper and lower surfaces of the liquid cooling plate 1. Specifically, the inner connecting portion 25 includes an outer equal thickness section 253 connected to the outer connecting portion 21 and having an equal thickness to the outer connecting portion 21, an inner equal thickness section 251 connected to the liquid cooling plate 1 and having an equal thickness to the liquid cooling plate 1, and a transition section 252 connecting the inner equal thickness section 251 and the outer equal thickness section 253, and the outer equal thickness section 253 is connected to the upper surface of the inner equal thickness section 251 in a flush and lower surface by a slope transition of the transition section 252.

In this embodiment, the side wall plate 2 is provided with a spoon-shaped lightening hole 24 at the inner connecting portion 25, specifically, the lightening hole 24 is provided at the transition portion of the outer equal thickness section 253 and the inner equal thickness section 251, so that the requirement of lightening the box body is satisfied while the strength of the box body is considered.

The bottom surface of the outer connection part 21 is lower than the bottom surface of the battery case 100, that is, the bottom surface of the outer connection part 21 is lower than the bottom surface of the liquid cooling plate 1, so that a gap is formed between the bottom surface of the liquid cooling plate 1 of the battery case 100 and the corresponding part of the bearing part of the battery case, and the gap can form an air heat insulation layer, so that heat exchange between the battery case and the corresponding part of the bearing part is avoided, and the cooling medium can be used for dissipating heat of the battery pack case more, so that the heat dissipation performance is improved.

A module middle cross beam 7 and a box middle cross beam 4 positioned between the module middle cross beams 7 are arranged on the bottom wall of the battery installation cavity, specifically, the box middle cross beam 4 divides the battery installation cavity into a plurality of battery accommodating units, the box middle cross beam 4 is perpendicular to the side wall plate 2, and two ends of the box middle cross beam 4 are respectively welded with the left side wall plate and the right side wall plate; the middle beam 7 of the module is parallel to the middle beam 4 of the box body, and two ends of the middle beam are respectively welded with the left side wall plate and the right side wall plate to divide the battery accommodating unit into a plurality of battery accommodating units. The battery module is fixedly installed in the battery accommodating unit, the bottom of the battery module is directly contacted with the liquid cooling plate 1 of the battery box body 100, and the battery module is cooled through the liquid cooling plate 1 of the battery box body 100. In this embodiment, four module middle cross beams 7 are provided, and one box middle cross beam 4 is provided.

Example 2 of battery case in the present utility model:

in embodiment 1, a crack stopper groove is provided at the junction of the side wall plate and the outer connecting portion. In this embodiment, no crack stop groove is provided.

Example 3 of battery case in the present utility model:

in embodiment 1, a weight-reducing gap is provided between adjacent outer connecting portions. In the embodiment, no weight reducing notch is arranged, and the supporting parts are not arranged at intervals; in other embodiments, a reinforcing connection plate is added between adjacent support portions.

Example 4 of battery case in the present utility model:

in embodiment 1, a scoop-shaped lightening hole is provided at the inner connecting portion. In this embodiment, no lightening holes are provided.

Example 5 of battery case in the present utility model:

in embodiment 1, the upper plate section of the side wall plate is disposed vertically, and the projection of the upper end of the upper plate section in the horizontal plane is located outside the projection of the lower end of the lower plate section in the horizontal plane. In this embodiment, the upper plate section gradually contracts from bottom to top into the box, and the projection of the upper end of the upper plate section in the horizontal plane is located outside the projection of the lower end of the lower plate section in the horizontal plane.

Example 6 of a battery case in the present utility model:

in embodiment 5, the side wall panel includes an upper plate section and a lower plate section, the upper plate section being disposed vertically, and the lower plate section being arcuate. In this embodiment, the upper plate section and the lower plate section of the side wall plate are integrally arc-shaped, that is, the lower plate section gradually contracts from top to bottom, and the upper plate section gradually contracts from bottom to top.

Example 7 of battery case in the present utility model:

in embodiment 6, the upper and lower plate sections of the side wall plate are curved as a whole. In this embodiment, the upper plate section and the lower plate section of the sidewall plate are integrally inclined, i.e., the lower plate section is gradually inclined from top to bottom, and the upper plate section is gradually inclined from bottom to top.

Example 8 of a battery case in the present utility model:

in embodiment 1, the inner connecting portion includes an outer equal thickness section connected to the outer connecting portion and having equal thickness with the outer connecting portion, an inner equal thickness section connected to the liquid cooling plate and having equal thickness with the liquid cooling plate, and a transition section connecting the outer equal thickness section and the inner equal thickness section, and upper and lower surfaces of the abutting portion of the inner connecting portion and the liquid cooling plate are flush with upper and lower surfaces of the liquid cooling plate, respectively. In this embodiment, the thickness of the inner connecting portion is equal to the thickness of the outer connecting portion, the upper surface of the abutting portion of the inner connecting portion and the liquid cooling plate is flush with the upper surface of the liquid cooling plate, and the lower surface of the abutting portion of the inner connecting portion and the liquid cooling plate is stepped with the lower surface of the liquid cooling plate.

Embodiments of the battery pack in the present utility model:

the battery pack comprises a battery module and a battery box body, wherein the battery box body is the battery box body recorded in any embodiment of the battery box body, and the description is omitted herein.

The above description is only a preferred embodiment of the present utility model, and the patent protection scope of the present utility model is defined by the claims, and all equivalent structural changes made by the specification and the drawings of the present utility model should be included in the protection scope of the present utility model.

Claims (10)

1. The battery box body comprises a bottom plate and peripheral side wall plates, and is characterized in that: at least one side wall plate comprises a lower plate section and an upper plate section connected with the lower plate section, wherein the lower plate section is arranged close to the bottom plate and gradually contracts into the box body from top to bottom; the upper plate section is vertically arranged, or the upper plate section gradually contracts into the box body from bottom to top, and the projection of the upper end of the upper plate section in the horizontal plane is positioned at the outer side of the projection of the lower end of the lower plate section in the horizontal plane.

2. The battery case according to claim 1, wherein: the lower plate section is arc-shaped.

3. The battery box according to claim 1 or 2, wherein: the side wall plate is arranged in a split mode with the bottom plate, the side wall plate further comprises an inner connecting portion connected with the lower plate section and extending into the box body and an outer connecting portion extending out of the box body, the inner connecting portion is fixedly connected with the bottom plate, and the outer connecting portion forms a fixed connecting portion for fixedly mounting the battery box body.

4. A battery compartment as claimed in claim 3, wherein: and a crack-stopping groove is formed in the transition position of the lower plate section and the outer connecting part.

5. A battery compartment as claimed in claim 3, wherein: the inner connecting part is internally provided with a lightening hole.

6. The battery case according to claim 5, wherein: the inner connecting part comprises an outer equal-thickness section which is connected with the outer connecting part and has equal thickness with the outer connecting part, the inner connecting part also comprises an inner equal-thickness section which is connected with the bottom plate and has equal thickness with the bottom plate, and the outer equal-thickness section is flush with the upper surface and the lower surface of the inner equal-thickness section and is in transitional connection through an inclined plane; the weight reducing holes are arranged at the transition part of the outer equal-thickness section and the inner equal-thickness section.

7. A battery compartment as claimed in claim 3, wherein: the inner connecting part is in butt joint with the bottom plate and is welded and fixed, and the upper surface and the lower surface of the butt joint part of the inner connecting part and the bottom plate are respectively flush with the upper surface and the lower surface of the bottom plate.

8. A battery compartment as claimed in claim 3, wherein: the inner connecting portion comprises an outer equal-thickness section which is connected with the outer connecting portion and is equal in thickness with the outer connecting portion, the inner connecting portion further comprises an inner equal-thickness section which is connected with the bottom plate and is equal in thickness with the bottom plate, and the outer equal-thickness section is flush with the upper surface and connected with the lower surface of the inner equal-thickness section through inclined plane transition.

9. A battery compartment as claimed in claim 3, wherein: the upper end of the upper plate section is provided with an outwardly extending connecting flange, and the projection of the outer side edge of the connecting flange in the horizontal plane is positioned outside or aligned with the projection of the outer side edge of the outer connecting part in the horizontal plane.

10. The battery package, including battery module and battery box, its characterized in that: the battery box is the battery box of any one of claims 1-9.