CN217507568U

CN217507568U - Battery pack

Info

Publication number: CN217507568U
Application number: CN202221548488.8U
Authority: CN
Inventors: 许久凌; 张勇杰; 张璐璐
Original assignee: China Lithium Battery Technology Co Ltd
Current assignee: China Lithium Battery Technology Co Ltd
Priority date: 2022-06-20
Filing date: 2022-06-20
Publication date: 2022-09-27
Anticipated expiration: 2032-06-20

Abstract

The utility model relates to a battery technology field provides a battery pack, including battery box and battery, the battery sets up in the battery box, and the battery includes: the battery comprises a battery shell, wherein a flange structure is arranged on the circumferential edge of the battery shell; the explosion-proof valve is arranged on the battery shell and faces the bottom surface of the battery box body; the flange structure is connected with the bottom surface of the battery box body, so that a gap is formed between the explosion-proof valve and the bottom surface of the battery box body. Through setting up the explosion-proof valve in battery case to the bottom surface towards battery box sets up, and has the clearance between the bottom surface of explosion-proof valve and battery box, thereby can avoid the bottom surface of battery box to block bursting of explosion-proof valve, with this assurance when battery case internal pressure reaches the default, explosion-proof valve bursts, and the battery can reliably release pressure, thereby guarantees the security performance of battery package.

Description

Battery pack

Technical Field

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

Background

In the related art, the battery inside the battery pack needs to release internal gas in time under the condition of thermal runaway, but the pressure release of the battery is sometimes influenced due to the limitation of the installation positions of the battery and the battery box.

SUMMERY OF THE UTILITY MODEL

The utility model provides a battery pack to improve the performance of battery pack.

The utility model provides a battery pack, including battery box and battery, the battery sets up in the battery box, and the battery includes:

the battery comprises a battery shell, wherein a flange structure is arranged on the circumferential edge of the battery shell;

the explosion-proof valve is arranged on the battery shell and faces the bottom surface of the battery box body;

the flange structure is connected with the bottom surface of the battery box body, so that a gap is formed between the explosion-proof valve and the bottom surface of the battery box body.

The utility model discloses the battery package includes battery box and battery, and the battery sets up in the battery box, through setting up the explosion-proof valve in battery case, and set up towards the bottom surface of battery box, and have the clearance between the bottom surface of explosion-proof valve and battery box, thereby can avoid the bottom surface of battery box to block the explosion-proof valve, guarantee with this when battery case internal pressure reaches the default, explosion-proof valve explodes, and the battery can reliably release pressure, thereby guarantee the security performance of battery package.

Drawings

For a better understanding of the present disclosure, reference may be made to the embodiments illustrated in the following drawings. The components in the drawings are not necessarily to scale, and related elements may be omitted in order to emphasize and clearly illustrate the technical features of the present disclosure. In addition, the relevant elements or components may be arranged differently as is known in the art. Further, in the drawings, like reference characters designate the same or similar parts throughout the several views. Wherein:

fig. 1 is a schematic diagram illustrating a structure of a battery pack according to an exemplary embodiment;

fig. 2 is a schematic structural view illustrating a battery pack according to another exemplary embodiment;

fig. 3 is a partial schematic structural view of a battery pack according to an exemplary embodiment;

FIG. 4 is a schematic diagram illustrating a plurality of batteries of a battery pack, according to an exemplary embodiment;

FIG. 5 is a schematic diagram illustrating a first perspective of a battery according to an exemplary embodiment;

FIG. 6 is a schematic diagram illustrating a second perspective of a battery according to an exemplary embodiment;

fig. 7 is an exploded view of a battery according to an exemplary embodiment.

The reference numerals are explained below:

1. a gap; 10. a battery case; 11. a heat exchange plate; 12. a gas flow channel; 20. a battery; 21. a battery case; 211. a flange structure; 212. a first surface; 213. a second surface; 214. recessing; 22. an explosion-proof valve; 23. a positive pole post assembly; 24. a negative pole post assembly; 25. a first housing member; 26. a second housing member; 30. an electric core; 31. a cell main body; 32. the pole ear portion.

Detailed Description

The technical solutions in the exemplary embodiments of the present disclosure will be clearly and completely described below with reference to the drawings in the exemplary embodiments of the present disclosure. The example embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the present disclosure, and it is, therefore, to be understood that various modifications and changes may be made to the example embodiments without departing from the scope of the present disclosure.

In the description of the present disclosure, unless otherwise explicitly specified or limited, the terms "first", "second", and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance; the term "plurality" means two or more; the term "and/or" includes any and all combinations of one or more of the associated listed items. In particular, reference to "the" object or "an" object is also intended to mean one of many such objects possible.

The terms "connected," "secured," and the like are to be construed broadly and unless otherwise stated or indicated, and for example, "connected" may be a fixed connection, a removable connection, an integral connection, an electrical connection, or a signal connection; "connected" may be directly connected or indirectly connected through an intermediate. The specific meaning of the above terms in the present disclosure can be understood by those skilled in the art as the case may be.

Further, in the description of the present disclosure, it is to be understood that the directional words "upper", "lower", "inner", "outer", etc., which are described in the exemplary embodiments of the present disclosure, are described at the angles shown in the drawings, and should not be construed as limiting the exemplary embodiments of the present disclosure. It will also be understood that, in this context, when an element or feature is referred to as being "on", "under", or "inner", "outer" with respect to another element(s), it can be directly on "," under ", or" inner "," outer "with respect to the other element(s), or indirectly on", "under", or "inner", "outer" with respect to the other element(s) via intervening elements.

An embodiment of the utility model provides a battery pack, please refer to fig. 1 to fig. 7, and battery pack includes battery box 10 and battery 20, and battery 20 sets up in battery box 10, and battery 20 includes: a battery case 21, a circumferential edge of the battery case 21 being provided with a flange structure 211; an explosion-proof valve 22, the explosion-proof valve 22 being provided in the battery case 21 and facing the bottom surface of the battery case 10; wherein the flange structure 211 is connected with the bottom surface of the battery case 10 such that the explosion-proof valve 22 has a gap 1 with the bottom surface of the battery case 10.

The utility model discloses a battery package includes battery box 10 and battery 20, battery 20 sets up in battery box 10, through setting up explosion-proof valve 22 in battery box 21, and set up towards the bottom surface of battery box 10, and have clearance 1 between the bottom surface of explosion-proof valve 22 and battery box 10, thereby can avoid the bottom surface of battery box 10 to block explosion-proof valve 22's explosion, guarantee with this when battery box 21 internal pressure reaches the default, explosion-proof valve 22 explodes, battery 20 can reliably release pressure, thereby guarantee the security performance of battery package.

It should be noted that, as shown in fig. 1 and fig. 2, there is a gap 1 between the explosion-proof valve 22 and the battery case 10, that is, the battery case 10 does not stop the explosion-proof valve 22, so that the explosion-proof valve 22 can be reliably opened, thereby ensuring the pressure relief capability of the battery.

The peripheral edge of the battery case 21 is provided with a flange structure 211, that is, the flange structure 211 may be provided on at least one side of the peripheral edge of the battery case 21, so that the flange structure 211 can be connected with the bottom surface of the battery case 10 to ensure that the explosion-proof valve 22 has a gap 1 with the battery case 10. The flange structure 211 may be in contact with only the bottom surface of the battery case 10, and the battery case 21 may be connected to the battery case 10 by other structures. Alternatively, the flange structure 211 can be fixedly connected to the battery case 10, for example, the flange structure 211 can be snapped into the battery case 10.

The flange structure 211 is provided not only to ensure the clearance 1 between the explosion-proof valve 22 and the battery case 10, but also to allow the flange structure 211 to dissipate heat from the battery 20.

The flange structure 211 may be formed by connecting the first and

second housing members

25 and 26, thereby improving the connection stability of the first and

second housing members

25 and 26. For example, the first and

second shells

25 and 26 may be welded, and the flange of the first shell 25 may be welded to the flange of the second shell 26, thereby forming a flange structure 211, thereby ensuring the connection stability of the first and

second shells

25 and 26.

In one embodiment, the explosion-proof valve 22 and the battery case 21 may be separated, that is, the battery case 21 may be provided with an explosion-proof hole, and the explosion-proof valve 22 is connected to the battery case 21, so as to shield the explosion-proof hole, and when the internal pressure of the battery case 21 reaches a preset value, the explosion-proof valve 22 is exploded, so as to implement pressure relief.

In one embodiment, the explosion-proof valve 22 and at least a portion of the battery case 21 are integrally formed, which not only simplifies the structure, but also reduces the number of manufacturing processes, thereby improving the forming efficiency of the explosion-proof valve 22.

The explosion-proof valve 22 is formed integrally with at least a part of the battery case 21, and for example, a part of the battery case 21 may be thinned to form the explosion-proof valve 22. Alternatively, the battery case 21 may be locally thinned during the molding process to serve as the explosion-proof valve 22, thereby achieving the pressure relief function, and the process is relatively simple, so that the molding efficiency of the explosion-proof valve 22 may be improved.

It should be noted that the explosion-proof valve 22 may be formed by scoring on the battery case 21, and the explosion-proof valve 22 may have a substantially linear structure, or the explosion-proof valve 22 may have a substantially annular structure, or the explosion-proof valve 22 may include straight and curved sections, etc., and the structural form of the explosion-proof valve 22 is not limited herein.

In one embodiment, as shown in fig. 5, the battery case 21 includes two opposing first surfaces 212 and four second surfaces 213 disposed around the first surfaces 212; wherein, the area of the first surface 212 is larger than that of the second surface 213, and the explosion-proof valve 22 is disposed on the second surface 213, so that the first surfaces 212 of the adjacent batteries 20 can be oppositely disposed, thereby improving the energy density of the battery pack, and ensuring that the explosion-proof valve 22 on the second surface 213 can face the bottom surface of the battery case 10.

It should be noted that the battery case 21 may be a square case, the two opposite first surfaces 212 are large surfaces of the battery case 21, the four second surfaces 213 are small surfaces of the battery case 21, the four second surfaces 213 include two pairs of small surfaces, that is, a first pair of small surfaces extending along the length direction of the battery case 21, and a second pair of small surfaces extending along the width direction of the battery case 21, and the area of the first pair of small surfaces is larger than that of the second pair of small surfaces, but smaller than that of the large surfaces.

In one embodiment, the battery 20 is bonded to the battery case 10, so that it is possible to ensure reliable connection of the battery 20 to the battery case 10. The battery case 21 of the battery 20 may be bonded to the battery case 10.

In one embodiment, a bonding layer is disposed between the battery 20 and the bottom surface of the battery case 10, and the bonding layer exposes at least a portion of the explosion-proof valve 22, so that the gap 1 is formed between the explosion-proof valve 22 and the bottom surface of the battery case 10, thereby preventing the bonding layer from shielding the explosion-proof valve 22 while ensuring reliable connection between the battery 20 and the battery case 10.

The bonding layer can be a heat-conducting adhesive, so that heat transfer between the battery 20 and the battery box body 10 is realized, and reliable connection between the battery 20 and the battery box body 10 can be realized, thereby improving the stability of the battery 20. The tie coat can be glued for the heat conduction structure, and battery 20 bonds through heat conduction structure glue with battery box 10, not only can guarantee the intensity of connecting to heat conduction structure glue can realize the heat transfer to this heat-sinking capability that improves battery 20.

In one embodiment, as shown in fig. 3, the battery box 10 includes a heat exchange plate 11, and the flange structure 211 is connected to the bottom surface of the heat exchange plate 11, so that a gap 1 is formed between the explosion-proof valve 22 and the heat exchange plate 11, thereby preventing the heat exchange plate 11 from blocking the explosion-proof valve 22, and thus ensuring that the explosion-proof valve 22 can be effectively exploded, thereby ensuring the safety performance of the battery.

The flange structure 211 is connected with the bottom surface of the heat exchanger plate 11, so that heat transfer between the battery case 21 and the heat exchanger plate 11 can be achieved through the flange structure 211.

The heat exchange plate 11 may be a heat exchange structure in the related art for achieving rapid heating or cooling of the battery 20. For example, the heat exchange plate 11 may be a liquid cooled plate.

In one embodiment, the battery case 10 includes a bottom plate, and the flange structure 211 is connected to a bottom surface of the bottom plate such that the explosion-proof valve 22 has a gap 1 therebetween. The bottom plate may not be integrated with the heat exchange channel, and the top of the battery 20 may be provided with the heat exchange structure.

In one embodiment, the bottom surface of the battery case 10 is provided with a gas flow channel 12 for the gas discharged from the inside of the battery 20 to flow, so that the gas discharged from the inside of a certain battery 20 can be ensured to be dispersed in time, and the problem of heat concentration can be avoided.

The bottom surface of the battery case 10 may be provided with a recess structure to form the gas flow channel 12, for example, the bottom surface of the battery case 10 may be provided with a recess structure at a position directly opposite to the explosion-proof valve 22 so that gas can be discharged through the gas flow channel 12 after the gas is discharged from the inside of the battery 20. When the adhesive layer is provided between the battery 20 and the bottom surface of the battery case 10, the adhesive layer avoids the gap 1, so that gas can enter the gas flow channel 12 through the gap 1.

In one embodiment, as shown in fig. 3, a gas flow channel 12 is formed between the bottom surface of the battery case 10 and the batteries 20 for the gas discharged from the interior of the batteries 20 to flow through, so that the gas discharged from the interior of one of the batteries 20 can be ensured to be dispersed in time, thereby avoiding the problem of heat concentration.

The flange structures 211 of two adjacent cells 20 may form a gas flow channel 12 therebetween, and the gap 1 may be a part of the gas flow channel 12. When a bonding layer is provided between the battery 20 and the bottom surface of the battery case 10, a gas flow channel 12 may be formed in the bonding layer to ensure rapid gas dispersion, thereby ensuring the safety of the battery pack.

In one embodiment, the battery 20 may include a plurality of explosion-proof valves 22, the plurality of explosion-proof valves 22 are disposed at intervals on the battery case 21, and the plurality of explosion-proof valves 22 are each disposed toward the bottom surface of the battery case 10.

In some embodiments, the battery 20 may include a plurality of explosion-proof valves 22, at least one explosion-proof valve 22 is disposed toward the top surface of the battery case 10, so that the upper and lower surfaces of the battery 20 may be provided with the explosion-proof valves 22, at least one explosion-proof valve 22 is disposed toward the bottom surface of the battery case 10, and at least one explosion-proof valve 22 is disposed toward the top surface of the battery case 10, as shown in fig. 2, so as to ensure that when thermal runaway occurs inside the battery 20, rapid pressure relief may be achieved through the plurality of explosion-proof valves 22, and when the adjacent batteries 20 are connected in series, the battery 20 may be connected in series by rotating 180 degrees, so that two types of batteries 20 are not specially designed, thereby reducing the difficulty of assembly.

In one embodiment, the number of the batteries 20 is multiple, and the explosion-proof valve 22 of each battery 20 is disposed toward the bottom surface of the battery box 10, so that it can be ensured that the gas discharged from the inside of the battery 20 can flow through the bottom of the battery box 10, and the top surface of the battery box can be protected to some extent, thereby preventing the gas from breaking through the top surface of the battery box 10 and causing injury to the driver of the vehicle body.

In one embodiment, as shown in fig. 3 to 5, the battery 20 further includes a positive electrode post assembly 23 and a negative electrode post assembly 24, the positive electrode post assembly 23 and the negative electrode post assembly 24 being respectively disposed at two ends of the battery case 21; two adjacent batteries 20 are connected in series, and the positive pole assembly 23 of one battery 20 and the negative pole assembly 24 of the other battery 20 face to the same side of the battery box body 10, so that the adjacent batteries 20 can be conveniently connected in series.

Considering that each of the batteries 20 is disposed toward the bottom surface of the battery box 10, and two adjacent batteries 20 are connected in series, the positive electrode post assembly 23 of one battery 20 and the negative electrode post assembly 24 of the other battery 20 face the same side of the battery box 10, that is, when the batteries 20 are grouped, the two adjacent batteries 20 are not in agreement in similarity, that is, the structural disposition positions of the batteries 20 are not in agreement, that is, the positive electrode post assembly 23 and the negative electrode post assembly 24 of the batteries 20 need to be switched.

In one embodiment, as shown in fig. 3 and 4, the positive pole assembly 23 of one battery 20 and the negative pole assembly 24 of the other battery 20 face the sides of the battery case 10; the battery case 21 is provided with a recess 214, the positive electrode post assembly 23 of one battery 20 is accommodated in the recess 214 of another battery 20, and the negative electrode post assembly 24 of one battery 20 is accommodated in the recess 214 of another battery 20, so that the space utilization rate of the batteries 20 in a group is improved, and the energy density of the battery pack is improved.

As shown in fig. 6, two recesses 214 are disposed on the battery housing 21, the two recesses 214 are respectively located at two ends of the battery housing 21, and the positive electrode post assembly 23 and the negative electrode post assembly 24 are respectively disposed on the surface of the battery housing 21 deviating from the recesses 214, so that when the batteries 20 are grouped, in two adjacent batteries 20, the positive electrode post assembly 23 of one battery 20 is accommodated in the recess 214 of another battery 20, and the negative electrode post assembly 24 of one battery 20 is accommodated in the recess 214 of another battery 20, thereby improving the space utilization rate when the batteries 20 are grouped, and thus improving the energy density of the battery pack.

In one embodiment, as shown in fig. 7, the battery cell 30 includes a battery cell main body 31 and two tab portions 32, where the tab portions 32 extend from a length direction of the battery cell main body 31; the two pole ear portions 32 are respectively connected to the positive pole post assembly 23 and the negative pole post assembly 24.

Two utmost point ear portions 32 can the direct weld with anodal utmost point post subassembly 23 and negative pole post subassembly 24 respectively, perhaps two utmost point ear portions 32 respectively with anodal utmost point post subassembly 23 and negative pole post subassembly 24 can be connected through the metal switching piece, and concrete connected mode can be the welding, also do not exclude to use modes such as riveting, do not limit here.

It should be noted that the battery cell main body 31 includes more than two pole pieces, the tab portion 32 includes more than two single-piece tabs, the single-piece tabs respectively extend from the pole pieces corresponding to the single-piece tabs, the width of the single-piece tabs is smaller than the width of the pole pieces, and the multiple single-piece tabs are stacked together to form the tab portion 32. Wherein the single tab is made of a metal foil having good electrical and thermal conductivity, such as aluminum, copper, nickel, or the like.

In one embodiment, as shown in fig. 7, the battery case 21 includes: a first housing piece 25; a second housing part 26, the second housing part 26 being connected to the first housing part 25 to enclose the electric core 30; the first housing member 25 is a flat plate, the positive electrode pole assembly 23 and the negative electrode pole assembly 24 are disposed on the first housing member 25, and the explosion-proof valve 22 is disposed on the second housing member 26.

In one embodiment, the battery case 21 may be made of stainless steel or aluminum, and has good corrosion resistance and sufficient strength.

It should be noted that the first housing member 25 and the second housing member 26 may be provided independently, as shown in fig. 5. In some embodiments, it is not excluded that the first and

second casing members

25, 26 may be a unitary structure, with the space for accommodating the battery core 30 being formed by stamping and subsequently being closed by welding.

In one embodiment, the thickness of the battery case 21 is 0.1mm to 0.5mm, so that the weight of the battery case 21 can be reduced, thereby increasing the energy density of the battery. The first shell 25 and the second shell 26 have a thickness of 0.1mm to 0.5 mm. The thickness of the battery case 21 is small, and in this embodiment, the explosion-proof valve 22 may be directly provided on the battery case 21, thereby facilitating molding.

The thickness of the battery case 21 may be 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, or 0.5mm, or the like.

In one embodiment, the length of the cell is a, 400mm a 2500mm, the width of the cell is b, the height of the cell is c, 2b a 50b, and/or 0.5c b 20 c.

Furthermore, b is more than or equal to 50mm and less than or equal to 200mm, and c is more than or equal to 10mm and less than or equal to 100 mm.

Preferably, 4 b.ltoreq.a.ltoreq.25 b, and/or 2 c.ltoreq.b.ltoreq.10 c.

In the battery in the above embodiment, the ratio of the length to the width of the battery is large, and further, the ratio of the width to the height of the battery is large, while sufficient energy density is ensured.

In one embodiment, the length of the battery is a, the width of the battery is b, the a is more than or equal to 4b and less than or equal to 7b, namely, the ratio of the length to the width of the battery is larger in the embodiment, so that the energy density of the battery is increased, and the battery pack is convenient to form subsequently.

In one embodiment, the height of the battery is c, b is more than or equal to 3c and less than or equal to 7c, and the ratio of the width to the height of the battery is larger, so that the battery is convenient to form under the condition of ensuring enough energy density.

Alternatively, the length of the cell may be 500mm to 1500mm, the width of the cell may be 80mm to 150mm, and the height of the cell may be 15mm to 25 mm.

The length of the battery is a dimension in the battery length direction, the width of the battery is a dimension in the battery width direction, and the height of the battery is a dimension in the battery height direction, that is, the thickness of the battery.

In one embodiment, the batteries are laminated batteries, which are convenient to pack and can be processed to obtain batteries with longer length.

The battery includes a cell and an electrolyte, and a minimum unit capable of performing an electrochemical reaction such as charge/discharge. The cell refers to a unit formed by winding or laminating a stacking part, wherein the stacking part comprises a first pole piece, a partition and a second pole piece. When the first pole piece is a positive pole piece, the second pole piece is a negative pole piece. And the polarities of the first pole piece and the second pole piece can be interchanged.

Specifically, the battery cell 30 is a laminated battery cell, and the battery cell 30 has a first pole piece, a second pole piece opposite to the first pole piece in electrical property, and a diaphragm piece disposed between the first pole piece and the second pole piece, so that a plurality of pairs of the first pole piece and the second pole piece are stacked to form the laminated battery cell.

Optionally, the battery may be a winding battery, that is, a first pole piece, a second pole piece opposite to the first pole piece in electrical property, and a diaphragm piece disposed between the first pole piece and the second pole piece are wound to obtain a winding battery cell.

It should be noted that a plurality of batteries may be formed into a battery module and then disposed in the battery case 10, and the plurality of batteries may be fixed by end plates and side plates. A plurality of cells may be directly provided in the battery case 10, i.e., without grouping the plurality of cells, and at this time, the end plates and the side plates may be removed.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and example embodiments be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

It will be understood that the present disclosure is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A battery pack characterized by comprising a battery case (10) and a battery (20), the battery (20) being provided to the battery case (10), the battery (20) comprising:

a battery case (21), wherein the peripheral edge of the battery case (21) is provided with a flange structure (211);

an explosion-proof valve (22), wherein the explosion-proof valve (22) is arranged on the battery shell (21) and faces the bottom surface of the battery box body (10);

wherein the flange structure (211) is connected with the bottom surface of the battery box body (10) so that a gap (1) is formed between the explosion-proof valve (22) and the bottom surface of the battery box body (10).

2. A battery pack according to claim 1, wherein the explosion-proof valve (22) is of integral construction with at least part of the battery housing (21).

3. The battery pack according to claim 1, wherein the battery case (21) includes two opposing first surfaces (212) and four second surfaces (213) disposed around the first surfaces (212);

wherein the area of the first surface (212) is larger than the area of the second surface (213), and the explosion-proof valve (22) is arranged on the second surface (213).

4. The battery pack according to claim 1, wherein the battery (20) is bonded to the battery case (10);

wherein a bonding layer is arranged between the battery (20) and the bottom surface of the battery box body (10), and the bonding layer exposes at least part of the explosion-proof valve (22) so that the gap (1) is reserved between the explosion-proof valve (22) and the bottom surface of the battery box body (10).

5. The battery pack according to claim 1, wherein the battery case (10) includes a heat exchange plate (11), and the flange structure (211) is coupled with a bottom surface of the heat exchange plate (11) such that the explosion-proof valve (22) and the heat exchange plate (11) have the gap (1) therebetween.

6. The battery pack according to claim 1, wherein a gas flow channel (12) is provided in a bottom surface of the battery case (10) to allow gas discharged from the inside of the battery (20) to flow therethrough.

7. The battery pack according to claim 1, wherein a gas flow passage (12) is formed between the bottom surface of the battery case (10) and the battery (20) to allow gas discharged from the inside of the battery (20) to flow therethrough.

8. The battery pack according to claim 1, wherein the battery (20) is plural, and the explosion-proof valve (22) of each battery (20) is provided toward the bottom surface of the battery case (10).

9. The battery pack according to claim 8, wherein the battery (20) further comprises a positive electrode post assembly (23) and a negative electrode post assembly (24), the positive electrode post assembly (23) and the negative electrode post assembly (24) being respectively disposed at two ends of the battery case (21);

the two adjacent batteries (20) are connected in series, and the positive pole post component (23) of one battery (20) and the negative pole post component (24) of the other battery (20) face to the same side of the battery box body (10).

10. A battery pack, according to claim 9, characterized in that the positive pole assembly (23) of one of the batteries (20) and the negative pole assembly (24) of the other battery (20) are directed towards the sides of the battery case (10);

wherein, be provided with sunken (214) on battery casing (21), positive pole post subassembly (23) of one battery (20) is held in sunken (214) of another battery (20).

11. The battery pack according to claim 1, wherein the explosion-proof valve (22) is plural, and at least one of the explosion-proof valves (22) is provided toward the top surface of the battery case (10).