CN216928782U

CN216928782U - Power battery cell and battery pack

Info

Publication number: CN216928782U
Application number: CN202123027745.1U
Authority: CN
Inventors: 杨伟; 胡明江; 张耀; 陈辉
Original assignee: Sunwoda Electric Vehicle Battery Co Ltd
Current assignee: Xinwangda Power Technology Co ltd
Priority date: 2021-12-02
Filing date: 2021-12-02
Publication date: 2022-07-08
Anticipated expiration: 2031-12-02

Abstract

The utility model provides a power battery cell and a battery pack, wherein the power battery cell comprises: the battery cell comprises a battery cell body and a shell assembly, wherein the battery cell body is arranged in the shell assembly, and an expansion gap is formed between the battery cell body and the shell assembly; the elastic component is arranged in the expansion gap. The power battery cell solves the problem of instability of the power battery cell in the prior art.

Description

Power battery cell and battery pack

Technical Field

The utility model relates to the technical field of batteries, in particular to a power battery cell and a battery pack.

Background

The current power battery cell is a closed space formed by a shell, a top cover and a matched sealing element, and a winding core, electrolyte, active substances, an insulating film and other components and various substances required by electrochemical energy conversion are arranged in the closed space. And roll up the core and at the charge and later stage charge-discharge cycle in-process, can constantly expand, and electric core inside can slowly produce gas, above two kinds of reasons all can lead to electric core macroscopical production trouble, and electric core design also outwards releases through the bulging with inside inflation through the aluminum hull promptly. The design requirement leaves out electric core inflation space when the module design, and present method is realized through the form of adding back the shape frame between two electric cores, and the mode of this kind of adding back the shape frame returns the shape frame when using and easily appears sliding scheduling problem, and the module initial pretightning force is undulant big, can all cause phenomenons such as later stage electric core inflation atress inequality, module size fluctuation, and then influences electric core performance.

SUMMERY OF THE UTILITY MODEL

The utility model mainly aims to provide a power battery cell and a battery pack, and aims to solve the problem of instability of the power battery cell in the prior art.

In order to achieve the above object, according to one aspect of the present invention, there is provided a power cell including: the battery cell comprises a battery cell body and a shell assembly, wherein the battery cell body is arranged in the shell assembly, and an expansion gap is formed between the battery cell body and the shell assembly; the elastic component is arranged in the expansion gap.

Furthermore, the battery cell body is provided with a first side surface and a second side surface which are symmetrically arranged, the elastic assembly comprises a first elastic plate and a second elastic plate, the first elastic plate is clamped between the first side surface and the shell assembly, and the second elastic plate is clamped between the second side surface and the shell assembly.

Furthermore, the distance between the first side surface and the shell assembly is d1, the thickness of the first elastic plate and the thickness of the second elastic plate are both d2, wherein d2/d1 is more than or equal to 0.8 and less than or equal to 1.2.

Further, the first elastic plate and the second elastic plate each have a plurality of hole structures.

Further, the hole structure is a blind hole, and the blind hole is arranged towards one side of the shell assembly.

Furthermore, the cell body is provided with a third side face and a fourth side face which are symmetrically arranged, a group of opposite edges of the first elastic plate and the second elastic plate are bent towards one side of the cell body to form a first side edge and a second side edge, the first side edge and the third side face are correspondingly arranged and clamped between the third side face and the shell assembly, and the second side edge and the fourth side face are correspondingly arranged and clamped between the fourth side face and the shell assembly.

Further, the thickness H of the battery cell body is D3, the width D of the first side edge is D4, wherein D4/D3 is more than or equal to 0.3 and less than or equal to 0.5.

Further, the elastic component is made of an insulating material.

Further, the elastic component adopts fluororubber or silica gel.

Further, the compression ratio of the elastic component is a, wherein a is more than or equal to 0.2 and less than or equal to 0.95.

Further, the bottom of the cell body and the shell assembly are provided with insulating sheets or insulating films.

Further, casing assembly's bottom is equipped with explosion-proof mouthful, and the edge of explosion-proof mouthful and the one end that is located casing assembly inboard are equipped with a week mounting groove, and the mounting groove forms first counter bore structure with explosion-proof mouthful, and wherein, power electricity core still includes explosion-proof valve, and explosion-proof valve setting is on the mounting groove.

Further, the edge of the explosion-proof opening and the end located on the inner side of the shell assembly are provided with a circle of bosses, the mounting groove is formed on the inner side of the edge of the boss, and the boss and the explosion-proof opening form a second counter bore structure.

Further, power electricity core still includes the protection casing, and the protection casing setting is between electric core body and explosion-proof mouthful, and protection casing and explosion-proof mouthful interval ground set up.

Further, the bottom of protection casing is equipped with a plurality of archs, and a plurality of archs set up at intervals, and wherein, explosion-proof valve sets up between two adjacent archs.

Furthermore, the protective cover is provided with a vent hole which is communicated with the explosion-proof valve.

According to another aspect of the utility model, a battery pack is provided, which includes a plurality of power battery cells, where the power battery cells are the power battery cells described above.

In order to facilitate the installation of the battery core body, the power battery core adopting the technical scheme of the utility model has the advantages that the space in the arranged shell assembly is larger than the volume of the battery core body, so that the battery core body is conveniently inserted into the shell assembly, and further, the battery core body can be stably fixed in the shell assembly to prevent shaking, an elastic assembly is also arranged between the battery core body and the shell assembly, the elastic assembly is made of elastic materials and can expand and contract, the insertion of the battery core body is facilitated, the battery core body can be fixed to prevent shaking, and the problem of unstable structure of the battery core is solved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the utility model and, together with the description, serve to explain the utility model and not to limit the utility model. In the drawings:

fig. 1 shows an assembly diagram of an embodiment of a power cell according to the utility model;

fig. 2 shows an exploded view of an embodiment of the power cell of the present invention;

fig. 3 is a schematic diagram illustrating a cell body and casing assembly cooperating embodiment of the power cell of the present invention;

FIG. 4 shows an exploded view of the embodiment of FIG. 3;

fig. 5 shows a schematic view of an embodiment of the resilient assembly of the power cell of the present invention;

fig. 6 shows a schematic view of an assembled embodiment of the housing assembly and the resilient assembly of the power cell of the present invention;

FIG. 7 shows an enlarged view at A in FIG. 6;

fig. 8 shows a cross-sectional view of an embodiment of a power cell of the present invention;

fig. 9 shows a partial cross-sectional view of an embodiment of a power cell of the present invention;

FIG. 10 shows an enlarged view of the dashed box portion of FIG. 9;

fig. 11 shows a schematic view of an explosion vent in an embodiment of a power cell of the present invention.

Wherein the figures include the following reference numerals:

10. a cell body; 11. a first side surface; 12. a second side surface; 13. a third side; 14. a fourth side; 15. a positive post; 16. a negative pole post; 20. a housing assembly; 21. an explosion-proof port; 211. mounting grooves; 212. a boss;

30. a first elastic plate; 31. a first side edge; 32. a second side edge; 33. blind holes; 34. a second elastic plate; 40. a top cover; 50. a conductive sheet; 60. an insulating sheet; 70. an explosion-proof valve; 80. a protective cover; 81. and (4) protruding.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

In order to solve the problem of instability of a power battery cell in the prior art, the utility model provides the power battery cell and a battery pack.

Referring to fig. 1 to 7, a power battery cell includes a battery cell body 10, a casing assembly 20, and an elastic assembly, wherein the battery cell body 10 is disposed in the casing assembly 20, and an expansion gap is formed between the battery cell body 10 and the casing assembly 20; the elastic component is disposed between the cell body 10 and the casing component 20.

In order to facilitate installation of the battery cell body 10, the space in the casing assembly 20 is larger than the volume of the battery cell body 10, so that the battery cell body 10 can be conveniently inserted into the casing assembly 20, and further, in order that the battery cell body 10 can be stably fixed in the casing assembly 20 to prevent shaking, an elastic assembly is arranged between the battery cell body 10 and the casing assembly 20, and is made of elastic materials and can expand and contract, so that the power battery cell is convenient to insert the battery cell body 10, and can fix the battery cell body 10 to prevent shaking, and the problem of unstable battery cell structure is solved.

The cell body 10 has a first side surface 11 and a second side surface 12 which are symmetrically arranged, the elastic assembly includes a first elastic plate 30 and a second elastic plate 34, the first elastic plate 30 is sandwiched between the first side surface 11 and the casing assembly 20, and the second elastic plate 34 is sandwiched between the second side surface 12 and the casing assembly 20.

The battery cell body 10 in this embodiment is a rectangular structure, the first side surface 11 and the second side surface 12 are two large symmetric surfaces on the battery cell body 10, when assembling the battery cell structure, the first elastic plate 30 and the second elastic plate 34 may be installed in two side walls of the casing assembly 20 correspondingly, then the battery cell body 10 is inserted into a space between the first elastic plate 30 and the second elastic plate 34 for positioning, the casing assembly 20 is a box structure with an unsealed top, the battery cell body 10 is inserted from the top of the casing assembly 20, and the casing assembly 20 is also a rectangular structure.

In addition, the elastic component may also be filled between the cell body 10 and the casing component 20 in the form of filler.

The distance between the first side 11 and the shell assembly 20 is d1, the thickness of the first elastic plate 30 and the second elastic plate 34 is d2, wherein d2/d1 is more than or equal to 0.8 and less than or equal to 1.2.

Preferably, the thickness of the first elastic plate 30 and the second elastic plate 34 in this embodiment is slightly larger than the distance from the first side 11 to the portion of the housing assembly 20 corresponding to the first side 11, so as to achieve better stability.

The first and second

resilient plates

30, 34 each have a plurality of aperture configurations. The hole structure is a blind hole 33, and the blind hole 33 is disposed toward one side of the housing assembly 20.

As shown in fig. 4 to fig. 7, the hole structure may be a through hole or a blind hole 33, in this embodiment, it is preferable that the hole structure is the blind hole 33, the blind hole 33 is disposed on a side corresponding to the casing assembly 20, and a side of the first elastic plate 30 and the second elastic plate 34 facing the cell body 10 is not provided with the hole structure, so that a surface of the first elastic plate 30 and the second elastic plate 34, which is attached to the cell body 10, is a smooth plane, a force applied to each position on the first elastic plate 30 and the second elastic plate 34 when the cell body 10 expands is the same, and if the hole structure is the through hole or the surface of the first elastic plate 30 and the second elastic plate 34, which is attached to the cell body 10, is not smooth, the force applied to each position when the cell expands is different, which causes a shape of the cell body 10, or even damages the cell body 10.

In addition, the blind hole 33 is located at a side close to the casing assembly 20, so that when the cell body 10 expands, the first elastic plate 30 and the second elastic plate 34 are pushed to compress and fit on the casing assembly 20, and a negative pressure cavity is formed between the compressed blind hole 33 and the casing assembly 20, so that the first elastic plate 30 and the second elastic plate 34 are firmly attached to the inner surface of the casing assembly 20, which is favorable for fixing the cell body 10.

The cell body 10 further has a third side 13 and a fourth side 14 symmetrically disposed, a set of opposite edges of the first elastic plate 30 and the second elastic plate 34 are bent toward the cell body 10 to form a first side 31 and a second side 32, the first side 31 and the third side 13 are correspondingly disposed and sandwiched between the third side 13 and the case assembly 20, and the second side 32 and the fourth side 14 are correspondingly disposed and sandwiched between the fourth side 14 and the case assembly 20.

As shown in fig. 3, the thicknesses of the first side 31 and the second side 32 in this embodiment are designed according to the distance between the cell body 10 and the casing assembly 20, and the first side 31 and the second side 32 are coated on two opposite surfaces of the cell body 10, so that the cell body 10 and each surface of the casing assembly 20 can be in butt contact with each other through the elastic assembly in the horizontal direction, and the cell body 10 is prevented from shaking in each direction.

The thickness H of the cell body 10 is D3, the width D of the first side 31 is D4, wherein D4/D3 is not less than 0.3 and not more than 0.5.

The arrangement in this embodiment ensures that after the first elastic plate 30 and the second elastic plate 34 are assembled, the first side edges 31 of the first elastic plate 30 and the second elastic plate 34 opposite to each other are not pressed together, which causes a problem of non-assembly.

The elastic component is made of insulating materials and made of fluororubber or silica gel. The fluororubber or the silica gel not only has the buffering function, but also gives consideration to insulation.

The compression ratio of the elastic component is a, wherein a is more than or equal to 0.2 and less than or equal to 0.95. This compression ratio can guarantee that battery cell body 10 can not cause the casing subassembly 20 inflation grow of outside when a great within range inflation yet, has protected casing subassembly 20 and battery cell body 10.

The bottom of the cell body 10 and the case assembly 20 are provided with an insulating sheet 60 or an insulating film. In this embodiment, the first elastic plate 30 and the second elastic plate 34 are in insulation connection with the casing assembly 20 around the horizontal direction of the battery cell body 10, and the bottom of the battery cell body 10 is in insulation connection with the casing assembly 20 through the insulation sheet 60, so that the insulation arrangement between the battery cell body 10 and the casing assembly 20 is ensured.

The bottom of casing assembly 20 is equipped with explosion-proof mouth 21, and the edge of explosion-proof mouth 21 and the one end that is located the casing assembly 20 inboard are equipped with a week mounting groove 211, and the mounting groove forms first counter bore structure with the explosion-proof mouth, and wherein, power electricity core still includes explosion-proof valve 70, and explosion-proof valve 70 sets up on mounting groove 211. A circle of bosses 212 are arranged at the edge of the explosion-proof opening 21 and at one end of the inner side of the shell assembly 20, and the mounting grooves 211 are arranged at the inner side of the edges of the bosses 212, wherein the bosses 212 and the explosion-proof opening 21 form a second counter bore structure.

As shown in fig. 8 to 11, the top cover 40 of the power battery cell of the present invention is no longer provided with an explosion-proof opening, but the bottom of the housing assembly is provided with an explosion-proof opening 21, the explosion-proof opening 21 is designed as a concave explosion-proof valve protection structure, specifically, the outer surface of the bottom of the aluminum housing is provided with an annular inner groove of the explosion-proof opening, the inner side of the bottom of the aluminum housing is provided with an annular inner boss, i.e., the annular boss, the inner side of the annular inner boss is provided with an annular explosion-proof valve assembly sink, i.e., the mounting groove, the explosion-proof valve is fixed by matching with the annular sink, and then sealed connection is achieved by welding.

The power battery cell further comprises a protective cover 80, the protective cover 80 is arranged between the battery cell body 10 and the explosion-proof port 21, and the protective cover 80 and the explosion-proof port 21 are arranged at intervals. The protective cover 80 is provided with a vent hole.

The casing subassembly in this embodiment adopts the aluminum hull, be provided with independent explosion-proof valve insulation protection casing 80 above the inboard annular boss in aluminum hull bottom, explosion-proof valve insulation protection casing 80 can directly place at aluminum hull bottom internal surface, also can glue in aluminum hull bottom internal surface through the double faced adhesive tape, certain space is left with the upper surface of explosion-proof valve to the regional lower surface of explosion-proof valve that explosion-proof valve insulation protection casing 80 corresponds, avoid directly pressing the explosion-proof valve, leave gas passage simultaneously, gas passage and air vent intercommunication, so that the gas of electricity core body release passes through air vent and explosion-proof mouthful intercommunication.

Preferably, when the explosion-proof valve 70 is mounted on the top of the housing assembly 20, the bottom of the cell body 10 is provided with an insulating sheet without the protective cover 80, and when the explosion-proof valve 70 is mounted on the bottom of the housing assembly 20, the protective cover 80 is provided between the bottom of the cell body 10 and the housing assembly 20 without the insulating sheet 60.

The bottom of the protective cover 80 is provided with a plurality of protrusions 81, the plurality of protrusions 81 are arranged at intervals, wherein the explosion-proof valve 70 is arranged in a groove formed between two adjacent protrusions 81, a vent hole is arranged in the groove to be communicated with the explosion-proof valve to form a gas channel, the explosion-proof valve is clamped in the groove, the explosion-proof valve is further positioned, the protrusions are abutted against the bottom of the shell, so that the protective cover is ensured not to be directly pressed on the explosion-proof valve,

in addition, the protective cover is made of insulating materials.

The utility model also provides a battery pack which comprises a plurality of power battery cells, wherein the power battery cells are the power battery cells.

The cell tab switching form is kept unchanged in a conventional form, that is, the cell body 10 is connected with the positive pole post 15 and the negative pole post 16 on the top cover 40 through the conducting strip 50. Two self-absorption expansion part elastic plates are installed on two large faces of the battery cell body 10, an insulating sheet 60 is installed at the bottom of the battery cell body 10, and then the shell assembly 20 is installed in the shell assembly 20, and the shell assembly 20 is made of aluminum shells. When the design of electric core body 10 thickness, consider good charge-discharge process and change, leave clearance d1 between electric core body 10 and aluminum hull, be about to roll up the later stage inflation restraint of core in the inside of aluminum hull, reduce or avoid electric core macroscopic expansion deformation on the aluminum hull outside by a wide margin. For the atress that rocks when reducing electric core vehicle-mounted application, consequently design in the clearance of installing between electric core body 10 and the aluminum hull from the absorption inflation part elastic plate. The first elastic plate 30 and the second elastic plate 34 are made of elastic insulating materials such as fluororubber and silica gel, the initial thickness d2 is 0.8-1.2 times of the unilateral clearance d1 between the cell body 10 and the large surface of the aluminum shell, and the compressible proportion range of the first elastic plate 30 and the second elastic plate 34 is 20% -95%. First elastic plate 30 and second elastic plate 34 structural design are many empty structures, can make things convenient for electrolyte to get into at initial condition, play the effect of storing a certain amount of free electrolyte promptly, and when later stage electricity core body 10 slowly expanded, first elastic plate 30 and second elastic plate 34 received the extrusion attenuation, extruded a certain amount of electrolyte simultaneously, are convenient for roll up the core pole piece and absorb the utilization. First elastic plate 30 and second elastic plate 34 side all are provided with first side 31 and second side 32, the height suggestion scope of first side 31 and second side 32 is 0.3 ~ 0.5 times of electric core body 10 thickness, leave the small clearance between first side 31 and the second side 32 of first elastic plate 30 and second elastic plate 34 of the electric core body 10 left and right sides when initial mounting promptly, this clearance is through first elastic plate 30 of electric core body 10 inflation compression and second elastic plate 34, the marginal portion of first elastic plate 30 and second elastic plate 34 all walks the material and fills along first side 31 direction. The big back of first elastic plate 30 and second elastic plate 34 all is provided with a plurality of blind holes 33, after electric core body and elastic component assembled income shell, electric core body 10 compresses first elastic plate 30 and second elastic plate 34, blind hole 33 is compressed and the big internal face wall face contact of aluminum hull, form certain negative pressure cavity between the big internal face wall face of blind hole 33 and aluminum hull, be convenient for fix between the wall of first elastic plate 30 and second elastic plate 34 and aluminum hull, be about to electric core body 10, first elastic plate 30, second elastic plate 34, the aluminum hull forms a whole that has the certain power effect.

From the above description, it can be seen that the above-described embodiments of the present invention achieve the following technical effects:

1) according to the utility model, the external expansion of the current battery core application state is converted into the shell, namely, the roll core expansion gap is reserved between the roll core and the aluminum shell in the roll core thickness design, the design can avoid the phenomena of the slippage of a clip frame between two battery cores in the existing module, the large fluctuation of the initial pre-tightening force of the module, the large fluctuation of the module size and the like, the expansion stress of the battery cores can be more uniform, and the normal design performance of the battery cores can be ensured.

2) The self-absorption expansion part elastic plate material selection compressible proportion is defined between 20% and 95%, a winding core can be fixedly protected in the initial stage, and the expansion space of the winding core can be compressed and released when the winding core expands in the later stage;

3) the elastic plate has insulation effect, can replace the existing winding core insulation sheet 60, has better heat conduction effect than the existing winding core insulation sheet 60 to a certain extent, is convenient for the overcurrent temperature of the winding core to be conducted to the metal shell, and is beneficial to heat dissipation;

4) according to the utility model, the back surfaces of the large surfaces of the first elastic plate 30 and the second elastic plate 34 are respectively provided with the negative pressure suction ports, and after the negative pressure suction ports are arranged in the shell together with the winding core, the negative pressure suction ports can form negative pressure adsorption with the inner wall surface of the large surface of the aluminum shell through the extrusion of the winding core, so that the winding core, the self-absorption expansion part and the aluminum shell can be fixed together to a certain extent, and the winding core is better fixed and protected.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail, but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

In the description of the present invention, it is to be understood that the orientation or positional relationship indicated by the orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc. are usually based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and in the case of not making a reverse description, these orientation words do not indicate and imply that the device or element being referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore, should not be considered as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "above … … surface," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and the terms have no special meanings unless otherwise stated, and therefore, the scope of the present invention should not be construed as being limited.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A power cell, comprising:

a cell body (10) and a casing assembly (20), wherein the cell body (10) is arranged in the casing assembly (20), and an expansion gap is formed between the cell body (10) and the casing assembly (20);

an elastomeric component disposed within the expansion gap.

2. The power cell of claim 1, wherein the cell body (10) has a first side surface (11) and a second side surface (12) arranged symmetrically, the elastic assembly comprises a first elastic plate (30) and a second elastic plate (34), the first elastic plate (30) is sandwiched between the first side surface (11) and the casing assembly (20), and the second elastic plate (34) is sandwiched between the second side surface (12) and the casing assembly (20).

3. The power cell of claim 2, wherein the first and second resilient plates (30, 34) each have a plurality of hole structures.

4. The power cell of claim 3, wherein the aperture structure is a blind aperture (33), the blind aperture (33) being disposed toward a side of the housing assembly (20).

5. The power cell of claim 2, wherein the cell body (10) further has a third side surface (13) and a fourth side surface (14) which are symmetrically arranged, a set of opposite edges of the first elastic plate (30) and the second elastic plate (34) are bent towards one side of the cell body (10) to form a first side edge (31) and a second side edge (32), the first side edge (31) and the third side surface (13) are correspondingly arranged and clamped between the third side surface (13) and the casing assembly (20), and the second side edge (32) and the fourth side surface (14) are correspondingly arranged and clamped between the fourth side surface (14) and the casing assembly (20).

6. The power cell of claim 1, wherein an explosion-proof opening (21) is formed in the bottom of the casing assembly (20), a circumference installation groove (211) is formed in one end of the edge of the explosion-proof opening (21) and located inside the casing assembly (20), the installation groove (211) and the explosion-proof opening (21) form a first counter bore structure, and the power cell further comprises an explosion-proof valve (70), and the explosion-proof valve (70) is disposed on the installation groove (211).

7. The power cell of claim 6, wherein a circumference boss (212) is arranged at an edge of the explosion-proof port (21) and at an end inside the housing assembly (20), the mounting groove (211) is arranged inside an edge of the boss (212), and the boss (212) and the explosion-proof port (21) form a second counter bore structure.

8. The power cell of claim 7, further comprising a protective cover (80), wherein the protective cover (80) is disposed between the cell body (10) and the explosion-proof opening (21), and wherein the protective cover (80) is disposed at a distance from the explosion-proof opening (21).

9. The power cell of claim 8, wherein the bottom of the protective cover (80) is provided with a plurality of protrusions (81), the plurality of protrusions (81) are arranged at intervals, and the explosion-proof valve (70) is arranged between two adjacent protrusions (81).

10. The power cell of claim 8, wherein the protective cover (80) is provided with a vent hole, and the vent hole is communicated with the explosion-proof valve (70).

11. A battery pack comprising a plurality of power cells, wherein the power cells are according to any one of claims 1 to 10.