CN218731381U

CN218731381U - Battery pack

Info

Publication number: CN218731381U
Application number: CN202222868681.6U
Authority: CN
Inventors: 王留杰; 纪文旭; 马豪
Original assignee: China Lithium Battery Technology Co Ltd
Current assignee: China Lithium Battery Technology Co Ltd
Priority date: 2022-10-28
Filing date: 2022-10-28
Publication date: 2023-03-24
Anticipated expiration: 2032-10-28

Abstract

The utility model relates to the technical field of batteries, in particular to a battery pack, which comprises a battery pack and a battery box body, wherein the battery pack is accommodated in the battery box body and comprises a plurality of battery units and a plurality of heat exchange plates, the battery units are arranged along a first direction, each battery unit is provided with a top surface, a bottom surface, two first side surfaces and two second side surfaces, the two first side surfaces are arranged oppositely, the two second side surfaces are arranged oppositely, the area of each first side surface is larger than that of each second side surface, the first side surface of each battery unit is provided with the heat exchange plate, and one heat exchange plate is shared between every two adjacent battery units; the battery box body comprises a bottom plate, the battery pack is borne on the bottom plate, and a plurality of cavities which are arranged at intervals are formed in the bottom plate. Through the structure design, the utility model discloses the bottom plate that utilizes to have the die cavity supports the group battery, when guaranteeing cooling performance, can promote the support effect to the group battery.

Description

Battery pack

Technical Field

The utility model relates to a battery technology field especially relates to a battery package.

Background

In the existing battery pack design, transverse beams and longitudinal beams for fixing a battery pack are arranged in a battery box body. However, when the battery pack adopts a battery to exchange heat on a large surface, that is, when a heat exchange plate is arranged between adjacent batteries, the battery pack cannot distinguish a plurality of regions, that is, transverse beams and longitudinal beams cannot be arranged, so that the battery box body of the battery pack has a poor support effect on the battery pack.

SUMMERY OF THE UTILITY MODEL

The utility model discloses a main aim at overcomes above-mentioned prior art's at least defect, provides the battery package to the support effect preferred of the group battery that adopts big face heat transfer.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

according to an aspect of the present invention, a battery pack is provided, wherein the battery pack includes a battery pack and a battery box, the battery pack is accommodated in the battery box and includes a plurality of battery units and a plurality of heat exchange plates, the plurality of battery units are arranged along a first direction, the battery units have a top surface, a bottom surface, and two first side surfaces and two second side surfaces arranged between the top surface and the bottom surface, the two first side surfaces are arranged oppositely, the two second side surfaces are arranged oppositely, the area of the first side surface is larger than that of the second side surface, the first side surface of the battery unit is provided with the heat exchange plate, and two adjacent battery units share one heat exchange plate; the battery box body comprises a bottom plate, the battery pack is borne on the bottom plate, and a plurality of cavities are arranged in the bottom plate at intervals.

According to the above technical scheme, the utility model provides an advantage and positive effect of battery package lie in:

the utility model provides a group battery of battery package adopts the group battery of "big face" heat transfer, is provided with the heat transfer board between the adjacent battery cell promptly. On the basis, a bottom plate for bearing the battery pack is provided with a plurality of cavities which are arranged at intervals. Through the structure design, the utility model discloses the bottom plate that the utilization has the die cavity supports the group battery, when guaranteeing cooling performance, can promote the support effect to the group battery.

Drawings

The various objects, features and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments of the invention, when considered in conjunction with the accompanying drawings. The drawings are merely exemplary of the invention and are not necessarily drawn to scale. In the drawings, like reference characters designate the same or similar parts throughout the different views. Wherein:

fig. 1 is a schematic perspective view illustrating a battery pack according to an exemplary embodiment;

fig. 2 is an enlarged schematic view of a portion a in fig. 1;

FIG. 3 is an enlarged schematic view of portion B of FIG. 1;

fig. 4 is an enlarged schematic view of portion C of fig. 1;

fig. 5 is a perspective view of a battery case of the battery pack shown in fig. 1;

FIG. 6 is an exploded perspective view of the battery housing shown in FIG. 5;

FIG. 7 is a partial cross-sectional view of the base plate shown in FIG. 5;

FIG. 8 is a partial cross-sectional view of the splice of two daughter boards of the backplane shown in FIG. 5;

fig. 9 is a perspective view of one of the battery cells shown in fig. 1;

fig. 10 and 11 are partial cross-sectional views of a splice of two sub-panels of a bottom panel of a battery pack according to two other exemplary embodiments, respectively;

fig. 12 is a partial cross-sectional view of a bottom plate of a battery pack according to another exemplary embodiment;

fig. 13 is a schematic perspective view illustrating one battery cell of a battery pack according to another exemplary embodiment;

FIG. 14 is a partial cross-sectional view of a splice of two sub-panels of a bottom panel of a battery pack according to another exemplary embodiment;

fig. 15 is a partial cross-sectional view of a battery pack according to another exemplary embodiment;

FIG. 16 is a partial cross-sectional view of a splice of two sub-panels of a bottom panel of a battery pack according to another exemplary embodiment;

fig. 17 is a partial sectional view of a battery pack according to another exemplary embodiment.

The reference numerals are explained below:

100. a battery pack;

110. a battery cell;

111. a battery cell;

112. a glue layer;

120. a heat exchange plate;

200. a battery case;

201. an end beam;

210. a base plate;

2101. a daughter board;

2102. welding marks;

211. a cavity;

212. a protrusion;

213. recessing;

214. lapping steps;

220. a bottom guard plate;

221. a second connecting member;

230. a frame;

231. a boss;

232. welding marks;

240. a seal member;

H1. wall thickness;

H2. wall thickness;

s1, a first side surface;

s2, a second side surface;

x. a first direction;

y. a second direction.

Detailed Description

Exemplary embodiments that embody features and advantages of the invention are described in detail below. It is to be understood that the invention is capable of other and different embodiments and its several details are capable of modification without departing from the scope of the invention, and that the description and drawings are to be regarded as illustrative in nature and not as restrictive.

In the following description of various exemplary embodiments of the invention, reference is made to the accompanying drawings, which form a part hereof, and in which are shown by way of illustration various exemplary structures, systems, and steps in which aspects of the invention may be practiced. It is to be understood that other specific arrangements of parts, structures, example devices, systems, and steps may be utilized, and structural and functional modifications may be made without departing from the scope of the present invention. Moreover, although the terms "over," "between," "within," and the like may be used in this specification to describe various example features and elements of the invention, these terms are used herein for convenience only, e.g., in accordance with the orientation of the examples described in the figures. Nothing in this specification should be construed as requiring a specific three dimensional orientation of structures to fall within the scope of the invention.

Referring to fig. 1, a schematic perspective view of a battery pack according to the present invention is representatively illustrated. In this exemplary embodiment, the present invention provides a battery pack that is applied to an in-vehicle battery as an example. It will be readily appreciated by those skilled in the art that various modifications, additions, substitutions, deletions, or other changes may be made to the embodiments described below in order to adapt the inventive arrangements to other types of battery devices, and still fall within the scope of the principles of the battery pack as set forth herein.

As shown in fig. 1, in an embodiment of the present invention, the battery pack provided by the present invention includes a battery pack 100 and a battery box 200, and the battery pack 100 is accommodated in the battery box 200. Referring to fig. 2 to 8 in combination, fig. 2 representatively illustrates an enlarged schematic view of portion a of fig. 1;

an enlarged schematic view of portion B of fig. 1 is representatively illustrated in fig. 3; an enlarged schematic view of portion C of fig. 1 is representatively illustrated in fig. 4; fig. 5 representatively illustrates a perspective view of the battery case 200; representatively illustrated in fig. 6 is a perspective exploded schematic view of the battery case 200; a partial cross-sectional view of the base plate 210 is representatively illustrated in fig. 7; a partial cross-sectional view of the splice of the two daughter boards 2101 is representatively illustrated in fig. 8. The structure, connection mode and functional relationship of the main components of the battery pack according to the present invention will be described in detail below with reference to the drawings.

As shown in fig. 1 to 6, in an embodiment of the present invention, a battery pack 100 includes a plurality of battery cells 110 and a plurality of heat exchange plates 120, and the battery cells 110 are arranged along a first direction X. Referring to fig. 9, each of the battery cells 110 has a top surface, a bottom surface, and two first side surfaces S1 and two second side surfaces S2 disposed between the top surface and the bottom surface, the two first side surfaces S1 are oppositely disposed, the two second side surfaces S2 are oppositely disposed, and the area of the first side surface S1 is larger than that of the second side surface S2. The first side surface S1 of the battery unit 110 (i.e., the "large surface" of the battery unit 110) is provided with a heat exchange plate 120, and one heat exchange plate 120 is shared between two adjacent battery units 110, that is, the battery pack 100 adopts a structural design of "large surface" heat exchange of the battery unit 110. On this basis, the battery box 200 includes a bottom plate 210, the battery unit 110 and the heat exchange plate 120 are carried on the bottom plate 210, and the bottom plate 210 has a plurality of cavities 211 arranged at intervals therein. Because the battery box 200 can't set up violently when the group battery 100 of "big face" heat transfer and group battery 100 does not have end plate isotructure to fix battery unit 110, through above-mentioned structural design, the utility model discloses the utilization has bottom plate 210 support group battery 100 of die cavity 211, when guaranteeing cooling performance, can promote the supporting effect to group battery 100.

As shown in fig. 5 to 7, in an embodiment of the present invention, the bottom plate 210 may include a plurality of sub-plates 2101, the sub-plates 2101 are spliced to form the bottom plate 210, and the sub-plates 2101 have cavities 211 therein. Because the restriction of the existing technology (for example extrusion moulding technology) of the panel of making to have die cavity 211 is difficult to the great panel of one shot forming size, through above-mentioned structural design, the utility model discloses can realize the manufacturing of the bottom plate 210 of the so-called large size, reduce the processing degree of difficulty, improve production efficiency. In some embodiments, for a small-medium sized battery pack or other processes, the bottom plate 210 may also be a unitary structure made of a single plate, and is not limited to this embodiment.

As shown in fig. 5 and 6, based on the structural design that the bottom plate 210 is formed by splicing a plurality of sub-boards 2101, in an embodiment of the present invention, the plurality of sub-boards 2101 may be arranged along the first direction X. On this basis, the cavities 211 may extend in a second direction Y perpendicular to the first direction X, and the cavities 211 may penetrate the sub-board 2101 in the second direction Y. Through the structure design, the utility model discloses can be perpendicular mutually with the extending direction design of die cavity 211 for the array orientation with a plurality of battery unit 110, further promote the supporting effect of bottom plate 210 to group battery 100 in view of the above. In some embodiments, when the backplane 210 is formed by splicing a plurality of daughter boards 2101, the plurality of daughter boards 2101 may be arranged in other directions, such as the second direction Y, although other arrangements of daughter boards 2101 may be used. Whether the bottom plate 210 is a single integral structure or a split structure of the sub-plates 2101, the extending direction of the cavity 211 of the bottom plate 210 may be other directions, for example, but not limited to, the arrangement direction (i.e., the first direction X) of the plurality of battery cells 110 of the battery pack 100, which is not limited to the embodiment.

As shown in fig. 6, based on the structural design that the bottom plate 210 is formed by splicing a plurality of sub-plates 2101, in an embodiment of the present invention, a plurality of cavities 211 may be provided in each sub-plate 2101, and a plurality of cavities 211 belonging to the same sub-plate 2101 may be arranged at intervals along the first direction X. Through the structure design, the utility model discloses can further promote the structural strength and the support stability of every daughter board 2101. In some embodiments, any one of the sub-boards 2101 may have only one cavity 211, which is not limited to this embodiment.

As shown in fig. 8, based on the structural design that the bottom plate 210 is formed by splicing a plurality of sub-boards 2101, in an embodiment of the present invention, a welded connection can be adopted between two adjacent sub-boards 2101, for example, two opposite end surfaces of two sub-boards 2101 shown in the drawings are respectively a spliced end surface, and two adjacent sub-boards 2101 are welded and connected via two opposite spliced end surfaces.

As shown in fig. 8, based on the design of the welded connection between two adjacent sub-boards 2101, in an embodiment of the present invention, two adjacent sub-boards 2101 are welded only on the surface facing away from the battery cell, which can be specifically understood by referring to the weld trace 2102 shown in fig. a. Through the structure design, because current welding process such as friction stir welding produces the pit in the welding department easily, the utility model discloses can avoid bottom plate 210 to produce the pit towards the surface of battery cell, guarantee bottom plate 210 towards the flatness on the surface of battery cell, further promote the support effect to battery cell.

Referring to fig. 14, a schematic partial cross-sectional view of a splice of two daughter boards 2101 of a backplane 210 of another exemplary embodiment of a battery pack that can embody principles of the present disclosure is representatively illustrated in fig. 14.

As shown in fig. 14, in an embodiment of the present invention, two adjacent sub-boards 2101 may be welded on both the surface facing the battery cell and the surface facing away from the battery cell, and may be specifically understood by referring to the welding trace 2102 shown in fig. a. Through the structure design, the utility model discloses can strengthen the joint strength of two adjacent daughter boards 2101, further promote bottom plate 210's structural strength from this.

Referring to fig. 15, a schematic partial cross-sectional view of a battery pack in another exemplary embodiment that can embody principles of the present invention is representatively illustrated in fig. 15.

As shown in fig. 15, in an embodiment of the present invention, still taking a design in which two adjacent sub-boards 2101 are welded on both surfaces facing and facing away from the battery unit as an example, a glue layer 112 may be disposed between the bottom board 210 (i.e., the sub-boards 2101) and the battery unit 110, i.e., the bottom board 210 and the battery unit 110 are adhered by the glue layer 112. Through the structure design, the utility model discloses can utilize glue film 112 to cover two blocks of daughter boards 2101 because of the pit that the welding produced towards battery unit 110's surface on the joint strength basis of strengthening two adjacent daughter boards 2101, can utilize glue film 112 to promote simultaneously with battery unit 110's joint strength.

As shown in fig. 8, in an embodiment of the present invention, two adjacent sub-boards 2101 respectively have opposite splicing end surfaces, and the cavity 211 of the sub-board 2101 is a cavity structure that is not opened at the splicing end surfaces. Through the structure design, the utility model discloses two blocks of daughter boards 2101's welding of can being convenient for avoids producing the warpage because of welding ability is too high, promotes welding quality. In some embodiments, referring to fig. 16, the cavity 211 of the sub-board 2101 may also be a cavity structure opened at the splicing end face, which is not limited to this embodiment.

As shown in fig. 8, in an embodiment of the present invention, a width of a weld between two adjacent sub-boards 2101 (for example, refer to a width of a weld mark 2102 shown in the figure) may be 5mm to 10mm, for example, 5mm, 6mm, 8mm, 10mm, and the like. In some embodiments, the width of the weld may also be less than 5mm, or may be greater than 10mm, such as 4mm, 11mm, and the like.

Referring to fig. 10, a schematic partial cross-sectional view of a splice of two adjacent daughter boards 2101 of a backplane 210 of another exemplary embodiment of a battery pack that can embody principles of the present disclosure is representatively illustrated in fig. 10.

As shown in fig. 10, in an embodiment of the present invention, a splicing structure may be disposed between two splicing end faces of two adjacent daughter boards 2101. Specifically, the plugging structure may include a protrusion 212 and a recess 213, the protrusion 212 is disposed on one of the splicing end surfaces, the recess 213 is disposed on the other splicing end surface, and the protrusion 212 and the recess 213 are plugged and matched. Through the structure design, the utility model discloses can further strengthen the welded connection's of two adjacent daughter boards 2101 intensity to further optimize the structural strength and the wholeness of bottom plate 210.

Referring to fig. 11, a schematic partial cross-sectional view of a splice of two adjacent daughter boards 2101 of a backplane 210 of another exemplary embodiment of a battery pack that can embody principles of the present disclosure is representatively illustrated in fig. 11.

As shown in fig. 11, in an embodiment of the present invention, an overlapping structure may be disposed between two splicing end faces of two adjacent sub-boards 2101. Specifically, the overlapping structure may include two overlapping steps 214 with matching shapes, the two overlapping steps 214 are respectively disposed on the two splicing end surfaces, and the two overlapping steps 214 are in overlapping engagement. Through the structure design, the utility model discloses can further strengthen the welded connection's of two adjacent daughter boards 2101 intensity to further optimize the structural strength and the wholeness of bottom plate 210.

As shown in fig. 6, in an embodiment of the present invention, the battery box 200 may further include a bottom protection plate 220, the bottom protection plate 220 is disposed at the bottom of the bottom plate 210, and the bottom protection plate 220 is connected to the plurality of sub-plates 2101 respectively. Through the structure design, the utility model discloses can utilize end backplate 220 to connect polylith daughter board 2101 respectively, strengthen the structural strength and the wholeness of the bottom plate 210 that constitutes by the concatenation of polylith daughter board 2101 from this.

Based on the structural design of the battery box 200 including the bottom guard plate 220, in an embodiment of the present invention, the bottom guard plate 220 and the sub-plate 2101 may be connected via a first connector, such as but not limited to a rivet bolt. On this basis, the first connector may correspond to the position of the cavity 211, i.e., the first connector is partially received in the cavity 211. Through the structure design, the utility model discloses can utilize the die cavity 211 to provide the usefulness of arranging the first connecting piece of part, the assembly of the first connecting piece of being convenient for especially utilizes first die cavity 211 to provide required inflation space when its assembly for the first connecting piece that adopts the blind rivet bolt. In some embodiments, when the battery box 200 includes the bottom cover 220, the bottom cover 220 can be connected to the sub-boards 2101 by other methods, such as welding, bonding, clipping, etc. Moreover, when the bottom protection plate 220 is connected to the sub-board 2101 via the first connecting member, the first connecting member may also correspond to a position where the cavity 211 is not disposed on the sub-board 2101, which is not limited by the present embodiment.

Based on the structural design that the battery box 200 includes the bottom protection plate 220, in an embodiment of the present invention, the battery box 200 may further include a frame 230, and the frame 230 is disposed around the bottom plate 210. On the basis, the bottom guard plate 220 and the frame 230 may be connected via a second connecting member. Through the structure design, the utility model discloses can further strengthen battery box 200's joint strength and structural integrity.

Referring to fig. 17, a schematic partial cross-sectional view of a battery pack in another exemplary embodiment that can embody principles of the present invention is representatively illustrated in fig. 17.

As shown in fig. 17, in an embodiment of the present invention, taking the battery case 200 as an example including the frame 230, the cavity 211 penetrates the bottom plate 210 along the extending direction thereof, and a cavity opening is formed at a side of the bottom plate 210. On this basis, the bezel 230 may be provided with a boss 231, and the boss 231 is inserted into the cavity 211 via the cavity opening. Through the structure design, the utility model discloses can further promote bottom plate 210 and frame 230's fixed strength.

As shown in fig. 17, based on the structural design that the frame 230 is inserted into the cavity 211 via the boss 231, in an embodiment of the present invention, the portion of the frame 230 provided with the boss 231 may be welded to the bottom plate 210.

As shown in fig. 17, based on the design that the frame 230 and the bottom plate 210 are welded, in an embodiment of the present invention, the portion of the frame 230 provided with the boss 231 and the bottom plate 210 may be welded only on the surface facing away from the battery cell, and specifically, the weld mark 232 shown in fig. may be referred to. Through the structure design, because current welding processes such as friction stir welding produce the pit in the welding department easily, the utility model discloses can avoid bottom plate 210 and frame 230's welding department to produce the pit towards the surface of battery cell, guarantee bottom plate 210 and frame 230's welding department towards the flatness on battery cell's surface, further promote the supporting effect to battery cell. In some embodiments, the portion of the frame 230 provided with the boss 231 and the bottom plate 210 may also be welded and connected at two surfaces facing and facing away from the battery cell, and the present embodiment is not limited thereto.

As shown in fig. 17, based on the design that the frame 230 and the bottom plate 210 are welded, in an embodiment of the present invention, the second connecting member 221 may be located outside the welding position of the frame 230 and the bottom plate 210.

As shown in fig. 17, based on the structural design that the second connection member 221 is located at the outer side of the welding position of the frame 230 and the bottom plate 210, in an embodiment of the present invention, a sealing member 240 may be disposed between the bottom plate 220 and the frame 230, and the sealing member 240 may be located between the bottom plate 210 and the second connection member 221.

Based on the structural design that battery box 200 includes frame 230, in the utility model discloses an embodiment, two tip along second direction Y can be fixed in two sides of frame 230 respectively for same piece daughter board 2101. Through the structure design, the utility model discloses can share the atress of bottom plate 210 to frame 230 along two sides that second direction Y is relative to this further promotes bottom plate 210's support intensity.

As shown in fig. 7, in an embodiment of the present invention, the wall thickness H1 of the bottom plate 210 at the top of the cavity 211 may be greater than or equal to 1.5mm, such as 1.5mm, 2mm, 3mm, 5mm, etc. Through the structure design, the utility model discloses can further promote bottom plate 210's structural strength, guarantee bottom plate 210 to group battery 100's supporting effect. In some embodiments, the wall thickness H1 of the bottom plate 210 at the top of the cavity 211 may also be less than 1.5mm, for example, 1.4mm, which is not limited to this embodiment.

As shown in fig. 7, in an embodiment of the present invention, the wall thickness H2 of the bottom plate 210 at the bottom of the cavity 211 may be greater than or equal to 1.5mm, for example, 1.5mm, 2mm, 3mm, 5mm, etc. Through the structure design, the utility model discloses can further promote bottom plate 210's structural strength, guarantee bottom plate 210 to group battery 100's supporting effect. In some embodiments, the wall thickness H2 of the bottom plate 210 at the top of the cavity 211 may also be less than 1.5mm, for example, 1.4mm, which is not limited to this embodiment.

As shown in fig. 7, in an embodiment of the present invention, the cross section of the cavity 211 may be rectangular. Through the structure design, the utility model has the advantages of simple structure, the processing of being convenient for etc. In some embodiments, the cavity 211 may have other shapes, such as, but not limited to, a trapezoid, and the like.

Referring to fig. 12, a partially cut-away schematic view of a bottom plate 210 of another exemplary embodiment of a battery pack that can embody principles of the present invention is representatively illustrated in fig. 12.

As shown in fig. 12, in an embodiment of the present invention, the cross section of the cavity 211 may be an oblong shape, and the term "oblong" refers to a shape formed by a rectangle and two semi-circles at both ends of the rectangle.

As shown in fig. 9, in an embodiment of the present invention, each battery unit 110 may include a plurality of battery cells 111, and the battery cells 111 are arranged along a second direction Y perpendicular to the first direction X. On the basis of this, the cavity 211 may extend in the second direction Y.

Referring to fig. 13, a schematic perspective view of a battery cell 110 in another exemplary embodiment of a battery pack that embodies principles of the present invention is representatively illustrated in fig. 13.

As shown in fig. 12, in an embodiment of the present invention, each battery unit 110 may also be a single battery cell 111.

It should be noted herein that the battery packs illustrated in the drawings and described in the present specification are but a few examples of the many types of battery packs that can employ the principles of the present invention. It should be clearly understood that the principles of the present invention are by no means limited to any details or any components of the battery pack as shown in the drawings or described in the present specification.

For example, as shown in fig. 3 to fig. 6, in an embodiment of the present invention, the battery box 200 may further include two end beams 201, where the two end beams 201 are respectively located at two ends of the battery pack 100 along the first direction X, and the battery pack 100 can be positioned in the first direction.

To sum up, the utility model provides a group battery 100 of battery package adopts the group battery 100 of "big face" heat transfer, is provided with heat transfer board 120 between the adjacent battery cell 110 promptly. On this basis, the bottom plate 210 for carrying the battery pack 100 has a plurality of cavities 211 arranged at intervals therein. Through the structure design, the utility model discloses the bottom plate 210 that utilizes to have die cavity 211 supports group battery 100, when guaranteeing cooling performance, can promote the supporting effect to group battery 100.

Exemplary embodiments of a battery pack proposed by the present invention are described and/or illustrated in detail above. Embodiments of the invention are not limited to the specific embodiments described herein, but rather, components and/or steps of each embodiment may be utilized independently and separately from other components and/or steps described herein. Each component and/or step of one embodiment can also be used in combination with other components and/or steps of other embodiments. When introducing elements/components/etc. described and/or illustrated herein, the articles "a," "an," and "the" are intended to mean that there are one or more of the elements/components/etc. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements/components/etc. other than the listed elements/components/etc. Furthermore, the terms "first" and "second" and the like in the claims and the description are used merely as labels, and are not numerical limitations of their objects.

While the present invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.

Claims

1. A battery pack is characterized by comprising a battery pack and a battery box body, wherein the battery pack is accommodated in the battery box body and comprises a plurality of battery units and a plurality of heat exchange plates, the battery units are arranged along a first direction, each battery unit is provided with a top surface, a bottom surface, two first side surfaces and two second side surfaces, the two first side surfaces and the two second side surfaces are arranged oppositely, the area of each first side surface is larger than that of each second side surface, the heat exchange plates are arranged on the first side surfaces of the battery units, and one heat exchange plate is shared between every two adjacent battery units; the battery box body comprises a bottom plate, the battery pack is borne on the bottom plate, and a plurality of cavities are arranged in the bottom plate at intervals.

2. The battery pack of claim 1, wherein the base plate comprises a plurality of sub-plates that are joined to form the base plate, the sub-plates having the cavities therein.

3. The battery pack of claim 2, wherein the plurality of sub-sheets are arranged in the first direction, the cavity extends in a second direction perpendicular to the first direction, and the cavity extends through the sub-sheets in the second direction.

4. A battery pack, as recited in claim 3, wherein each of the sub-plates has a plurality of cavities therein, the cavities being spaced apart along the first direction.

5. The battery pack of claim 2, wherein the sub-plates are welded to each other.

6. The battery pack according to claim 5, wherein two adjacent sub-plates are welded at both a surface facing the battery cell and a surface facing away from the battery cell.

7. The battery pack of claim 6, wherein a glue layer is disposed between the bottom plate and the battery cell, and the bottom plate and the battery cell are bonded via the glue layer.

8. The battery pack according to claim 5, wherein two adjacent sub-plates are welded only at a surface facing away from the battery cell.

9. The battery pack according to claim 5, wherein two adjacent sub-plates respectively have opposite spliced end faces, and the cavity is a cavity structure which is not opened at the spliced end faces.

10. The battery pack according to claim 5, wherein the width of the weld between two adjacent sub-plates is 5mm to 10mm.

11. The battery pack according to claim 5, wherein two adjacent daughter boards respectively have opposite splicing end faces, an insertion structure is disposed between the two splicing end faces, the insertion structure includes a protrusion and a recess, the protrusion is disposed on one of the splicing end faces, the recess is disposed on the other splicing end face, and the protrusion is inserted into and matched with the recess.

12. The battery pack according to claim 5, wherein two adjacent sub-boards respectively have opposite splicing end faces, an overlapping structure is arranged between the two splicing end faces, the overlapping structure comprises two overlapping steps with matched shapes, the two overlapping steps are respectively arranged on the two splicing end faces, and the two overlapping steps are in overlapping fit.

13. The battery pack according to any one of claims 2 to 12, wherein the battery case further includes a bottom cover plate disposed at a bottom of the bottom plate, and the bottom cover plate is connected to the plurality of sub-boards, respectively.

14. The battery pack of claim 13, wherein the bottom guard plate and the sub-plate are connected via a first connector; the first connecting piece corresponds to the position of the cavity and is partially accommodated in the cavity.

15. The battery pack of claim 13, wherein the battery case further comprises a frame disposed around the bottom plate; the bottom guard plate is connected with the frame through a second connecting piece.

16. The battery pack according to claim 15, wherein the cavity extends through the bottom plate in the extending direction of the cavity, and a cavity opening is formed at a side edge of the bottom plate; the frame is provided with a boss, and the boss is inserted into the cavity through the cavity opening.

17. The battery pack according to claim 16, wherein the portion of the frame on which the boss is provided is welded to the base plate.

18. The battery pack according to claim 17, wherein the portion of the frame on which the bosses are provided is welded to the base plate only at a surface facing away from the battery cell.

19. The battery pack of claim 17, wherein the second connecting member is located outside a weld of the frame and the base plate.

20. The battery pack of claim 19, wherein a seal is disposed between the backplate and the rim, the seal being positioned between the base plate and the second connector.

21. The battery pack according to any one of claims 1 to 12, wherein:

the wall thickness of the bottom plate positioned at the top of the cavity is greater than or equal to 1.5mm; and/or

The wall thickness of the bottom plate at the bottom of the cavity is greater than or equal to 1.5mm.

22. The battery pack according to any one of claims 1 to 12, wherein the cavity has a rectangular, oblong or trapezoidal cross-section.

23. The battery pack according to any one of claims 1 to 12, wherein the battery unit includes a plurality of battery cells arranged in a second direction perpendicular to the first direction; wherein the cavity extends in the second direction.