CN220065869U - Cover plate, battery monomer, battery and electric equipment - Google Patents

Abstract

The utility model relates to a cover plate, a battery monomer, a battery and electric equipment. The cover plate comprises an explosion-proof area and a non-explosion-proof area distributed around the explosion-proof area, wherein the explosion-proof area is provided with explosion-proof nicks, the non-explosion-proof area is provided with a supporting boss protruding out of one side surface of the cover plate, and the supporting boss is used for being abutted with the collecting disc. Therefore, the support boss is arranged in the non-explosion-proof area, so that on one hand, the explosion-proof area of the cover plate is prevented from being directly contacted with the current collecting disc, the explosion-proof area of the cover plate cannot be subjected to the pressure of the current collecting disc, namely, the explosion-proof nick cannot be in a stressed state when thermal runaway does not occur, and the service life of the cover plate is greatly prolonged; on the other hand, the supporting boss can play a role in reinforcing the rigidity of the cover plate, so that the cover plate can be thinned as much as possible on the premise that the rigidity of the cover plate meets the requirement, and the weight of the battery monomer can be reduced.

Description

Cover plate, battery monomer, battery and electric equipment

Technical Field

The utility model relates to the technical field of batteries, in particular to a cover plate, a battery monomer, a battery and electric equipment.

Background

Batteries are widely used in various devices such as cellular phones, notebook computers, battery cars, electric vehicles, electric airplanes, electric ships, electric toy vehicles, electric toy ships, electric toy airplanes, electric tools, and the like. The battery cell is an important component of the battery and generally comprises a shell, and an electric core assembly and a current collecting disc which are accommodated in the shell. One end of the housing has an opening that is sealed by a cover plate to enclose the cell assembly and current collecting tray within the interior of the housing. In order to prevent explosion when the battery cell body is out of control, an explosion-proof notch needs to be formed in the cover plate, and when the pressure in the shell reaches a threshold value, the explosion-proof notch bursts to release pressure.

Conventionally, the cover plate is directly attached to and tightly pressed against the current collecting disc, and as the battery cell assembly expands in the process of electrolyte infiltration and subsequent use, the current collecting disc is further pushed to be attached to the cover plate, so that an explosion-proof nick area on the cover plate is mutually abutted to the current collecting disc, and the explosion-proof nick is always in a stressed state. The explosion-proof nicks are in a stressed state for a long time, micro defects such as micro cracks, material fatigue and the like are easily generated at the explosion-proof nicks, and the service life of the cover plate is greatly reduced.

Disclosure of Invention

Based on this, it is necessary to provide a cover plate, a battery cell, a battery and electric equipment for improving the above-mentioned defects, aiming at the problem that the explosion-proof nick on the cover plate is mutually abutted with the current collecting disc in the prior art, so that the explosion-proof nick is always in a stress state, and the service life of the cover plate is greatly reduced.

The utility model provides a apron, includes explosion-proof district and around explosion-proof district that the explosion-proof district laid, explosion-proof nick has been seted up in explosion-proof district, explosion-proof district be provided with protruding in the support boss of one side surface of apron, the apron is used for through support boss and mass flow disk butt.

In one embodiment, the cover plate further has a first side and a second side opposite to each other, and the support boss protrudes from the first side surface of the cover plate;

the explosion-proof area is arranged from the second side of the cover plate to the first side in a protruding mode, and the height of the explosion-proof area protruding out of the surface of the first side is lower than the height of the supporting boss protruding out of the surface of the first side.

In one embodiment, the difference between the height of the explosion-proof area protruding from the first side surface and the height of the supporting boss protruding from the first side surface is 0.2mm to 0.8mm.

In one embodiment, the support boss is annular in shape and is disposed around the explosion-proof area.

In one embodiment, the support boss includes at least two, at least two of which are each disposed around the explosion-proof area and spaced apart from each other in a radial direction of the cover plate.

In one embodiment, each of the support bosses comprises a plurality of sub-segments, the respective sub-segments of each of the support bosses being commonly spaced around the explosion-proof area.

In one embodiment, in any set of two adjacent support bosses, each of the subsections of one of the support bosses is arranged offset from each of the subsections of the other support boss in the radial direction of the cover plate.

In one embodiment, the cover plate further has a first side and a second side opposite to each other, and a portion of the non-explosion-proof area is protruded from the second side toward the first side to form a groove at the second side and the support boss at the first side.

A battery cell comprising:

a housing having an opening;

the battery cell assembly is accommodated in the shell;

the current collecting disc is accommodated in the shell and is positioned at one side of the battery cell assembly, which faces the opening;

the cover plate according to any one of the above embodiments, wherein the cover plate is sealingly disposed at the opening of the housing, and abuts against the collecting tray through the supporting boss.

A battery comprising a battery cell as described in any one of the embodiments above.

A powered device comprising a battery cell as described in any of the embodiments above or a battery cell as described in any of the embodiments above.

According to the cover plate, the battery monomer, the battery and the electric equipment, the supporting boss is arranged in the non-explosion-proof area, and the cover plate is abutted to the current collecting disc through the supporting boss, so that the explosion-proof area of the cover plate is prevented from being directly contacted with the current collecting disc, the pressure of the current collecting disc cannot be applied to the explosion-proof area of the cover plate, namely, the explosion-proof nick cannot be in a stress state when thermal runaway does not occur, and the service life of the cover plate is greatly prolonged; on the other hand, the supporting boss can play a role in reinforcing the rigidity of the cover plate, so that the cover plate can be thinned as much as possible on the premise that the rigidity of the cover plate meets the requirement, and the weight of the battery monomer can be reduced.

Drawings

Fig. 1 is a cross-sectional view of a battery cell according to an embodiment of the present utility model;

fig. 2 is a front view of a cap plate of the battery cell shown in fig. 1;

fig. 3 is a partial enlarged view of the battery cell shown in fig. 1 at the opening of the case;

fig. 4 is a cross-sectional view of the cover plate shown in fig. 2 along A-A.

Detailed Description

In order that the above objects, features and advantages of the utility model will be readily understood, a more particular description of the utility model will be rendered by reference to the appended drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present utility model. The present utility model may be embodied in many other forms than described herein and similarly modified by those skilled in the art without departing from the spirit of the utility model, whereby the utility model is not limited to the specific embodiments disclosed below.

In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present utility model.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present utility model, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

In the present utility model, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present utility model, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

It will be understood that when an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like are used herein for illustrative purposes only and are not meant to be the only embodiment.

In one embodiment of the utility model, a battery is provided that refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery referred to in the present utility model may include a battery module, a battery pack, or the like. In particular, the battery generally includes a case for enclosing one or more battery cells. The case body can prevent liquid or other foreign matters from affecting the charge or discharge of the battery cells. Specifically, in the battery, the number of the battery cells may be one or more. If the number of the battery cells is multiple, the multiple battery cells can be connected in series or in parallel or in series-parallel connection, and the series-parallel connection means that the multiple battery cells are connected in series or in parallel. The battery modules can be formed by connecting a plurality of battery monomers in series or in parallel or in series-parallel connection, and the battery modules are connected in series or in parallel or in series-parallel connection to form a whole and are accommodated in the box body. Or all the battery cells can be directly connected in series or in parallel or in series-parallel, and then the whole formed by all the battery cells is accommodated in the box body.

It is understood that the battery cell may include a lithium ion secondary battery cell, a lithium ion primary battery cell, a lithium sulfur battery cell, a sodium ion battery cell, or a magnesium ion battery cell, which is not limited in the embodiment of the utility model. The battery cell may be in a cylindrical shape, a flat shape, a rectangular parallelepiped shape, or other shapes, which is not limited in this embodiment of the utility model. The battery cells are generally classified into three types according to the packaging method: the cylindrical battery cell, the square battery cell and the soft package battery cell are not limited in this embodiment.

Referring to fig. 1 to 4, an embodiment of the utility model provides a battery cell, which includes a housing 10, a cell assembly 20, a current collecting plate 30 and a cover plate 40. The housing 10 has an opening 11, the cell assembly 20 and the current collecting plate 30 are disposed inside the housing 10 through the opening 11, and the current collecting plate 30 is located at a side of the cell assembly 20 facing the opening 11. The cap plate 40 is sealingly disposed at the opening 11 of the case 10, thereby preventing the electrolyte within the case 10 from leaking out of the opening 11 of the case 10.

The cover plate 40 includes an explosion-proof area 41 and a non-explosion-proof area 42 disposed around the explosion-proof area 41. The explosion-proof area 41 is provided with an explosion-proof notch 43, a large amount of gas or jet is generated when the battery cell assembly 20 is in thermal runaway, and the explosion-proof area 41 of the cover plate 40 bursts along the explosion-proof notch 43 under the impact of the high-pressure air flow or jet, so that pressure relief is realized, and explosion of the battery cell is avoided. The non-explosion-proof area 42 of the cap plate 40 has a support boss 44 protruding from one side surface of the cap plate 40, and the cap plate 40 abuts against the collecting tray 30 through the support boss 44.

In this way, the support boss 44 is arranged in the non-explosion-proof area 42, and the cover plate 40 is abutted against the current collecting disc 30 through the support boss 44, so that on one hand, the explosion-proof area 41 of the cover plate 40 is prevented from directly contacting with the current collecting disc 30, the explosion-proof area 41 of the cover plate 40 is prevented from being subjected to the pressure of the current collecting disc 30, namely, the explosion-proof nicks 43 are prevented from being in a stress state when thermal runaway does not occur, and the service life of the cover plate 40 is greatly prolonged; on the other hand, the supporting boss 44 can play a role in reinforcing the rigidity of the cover plate 40, so that the cover plate 40 can be thinned as much as possible on the premise that the rigidity of the cover plate 40 meets the requirement, and the weight of the battery cell can be reduced.

It should be noted that, in the prior art, the cover plate 40 and the collecting tray 30 are in a large-surface contact manner, so that the requirement on the flatness of the cover plate 40 is high. In contrast, in the embodiment of the present utility model, the cover plate 40 contacts the current collecting plate 30 through the supporting boss 44, so that the contact area between the cover plate and the current collecting plate is reduced, the requirement on the flatness of the cover plate 40 is reduced, and the processing difficulty and the processing cost of the cover plate 40 are saved.

In particular to the embodiment, the cover 40 is welded to the opening 11 of the housing 10, so that on one hand, the cover 40 is fixedly connected to the housing 10, and on the other hand, the cover 40 seals the opening 11.

In the embodiment, the peripheral edge of the collecting tray 30 is turned towards the same side of the collecting tray 30 to form a flange 32, and the flange 32 is attached to and welded with the inner wall of the casing 10, so that the collecting tray 30 is fixedly connected with the casing 10. Of course, in other embodiments, the collecting tray 30 may be tightly fitted to the inner wall of the housing 10 by the flange 32, so as to fix the collecting tray 30 to the housing 10.

In particular, in the embodiment, the current collecting disc 30 is provided with a through hole 31, and the through hole 31 is opposite to the explosion-proof area 41 on the cover plate 40, so that high-pressure air flow or jet can pass through the through hole 31 when the cell assembly 20 is in thermal runaway, and act on the explosion-proof area 41 of the cover plate 40, and further the explosion-proof area 41 bursts along the explosion-proof notch 43 to release pressure.

In the embodiment of the present utility model, the cover plate 40 has a first side a1 and a second side a2 as opposite sides thereof. The first side a1 of the cover plate 40 faces the collector plate 30 and the second side a2 of the cover plate 40 faces away from the collector plate 30. The support boss 44 protrudes from the surface of the first side a1 of the cap plate 40, so that the cap plate 40 abuts against the collecting tray 30 through the support boss 44. The explosion-proof area 41 protrudes outward from the second side a2 of the cover plate 40 toward the first side a1, so that the explosion-proof area 41 is recessed inward at the surface of the second side a2 of the cover plate 40 and protrudes outward at the surface of the first side a1 of the cover plate 40. And, the height that explosion-proof area 41 protrusion is higher than the height that support boss 44 protrusion is in the first side a1 surface of apron 40 in apron 40 to support boss 44 and current collecting tray 30 butt, and explosion-proof area 41 can not contact with current collecting tray 30, prevents explosion-proof area 41 and receives current collecting tray 30's pressure and reduce apron 40's life.

It should be noted that, since the explosion-proof area 41 protrudes outward from the second side a2 of the cover plate 40 toward the first side a1, the surface of the explosion-proof area 41 on the second side a2 of the cover plate 40 is recessed inward, so that the explosion-proof area 41 can be prevented from being directly contacted with other components on the second side a2 of the cover plate 40, and the service life of the cover plate 40 is further prevented from being shortened due to the fact that the explosion-proof area 41 of the cover plate 40 is in a stressed state.

Alternatively, the difference between the height of the explosion-proof area 41 protruding from the surface of the first side a1 of the cover plate 40 and the height of the support boss 44 protruding from the surface of the first side a1 of the cover plate 40 is 0.2mm to 0.8mm. I.e., the gap between the burst region 41 and the current collecting plate 30 is 0.2mm to 0.8mm. Specifically, the difference between the height of the explosion-proof area 41 protruding from the surface of the first side a1 and the height of the supporting boss 44 protruding from the surface of the first side a1 may be 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, or the like.

Alternatively, the thickness of the cover 40 at the explosion vent 43 is 0.025mm to 0.1mm. The thickness of the cover plate 40 at the explosion-proof notch 43 may be related to the pressure threshold of the explosion-proof opening, and may be designed according to the specific situation, and is not limited herein.

In particular, in the embodiment, the explosion-proof area 41 is provided with a liquid injection hole 410, and the liquid injection hole 410 is sealed by the sealing nail 60. In this way, the cover plate 40 can be used to dock with the injection nozzle of the injection device during injection, and then the injection nozzle of the injection device injects electrolyte into the casing 10 through the injection hole 410 of the explosion-proof area 41. After the injection is completed, the injection hole 410 is sealed by the sealing pin 60. On the one hand, when the electrolyte is injected, the electrolyte leaks outwards, and as the explosion-proof area 41 is recessed inwards at the second side a2 of the cover plate 40, the leaked electrolyte can be gathered in the recess so as to be convenient for cleaning; on the other hand, since the explosion-proof area 41 is recessed inward on the second side a2 of the cover plate 40, the non-explosion-proof area 42 of the cover plate 40 mainly receives the acting force of abutting against the liquid injection nozzle of the liquid injection device during liquid injection, so as to avoid the reduction of the service life of the cover plate 40 caused by the larger acting force received by the explosion-proof nick 43 of the explosion-proof area 41.

Further, the injection hole 410 of the cover plate 40, the through hole 31 of the current collecting plate 30, and the central hole 21 of the cell assembly 20 are arranged substantially coaxially. Thus, on the one hand, the electrolyte injected from the injection hole 410 can enter the central hole 21 of the cell assembly 20 through the through hole 31, and then enter the interior of the cell assembly 20 again, so as to infiltrate the cell assembly 20; on the other hand, in the event of thermal runaway of the cell assembly 20, high pressure air flow or jets can pass through the through-holes 31 and act on the explosion-proof area 41 of the cover plate 40 such that the explosion-proof area 41 bursts along the explosion-proof score 43 to relieve pressure.

In the embodiment of the present utility model, the portion of the non-explosion-proof area 42 protrudes from the second side a2 of the cover plate 40 toward the first side a1 of the cover plate 40, so as to form a groove on the second side a2 of the cover plate 40, and form the supporting boss 44 on the first side a1 of the cover plate 40. Thus, the supporting boss 44 can be formed by a stamping process, which is simple and efficient.

Referring to fig. 2, in the embodiment of the present utility model, the supporting boss 44 is annular and is disposed around the explosion-proof area 41, so that the abutting structure of the cover plate 40 and the collecting tray 30 is more stable and reliable, and the rigidity of the cover plate 40 is better enhanced.

In particular embodiments, the support boss 44 includes at least two support bosses 44, each of which is disposed about the explosion-proof region 41. And, each support boss 44 is arranged at intervals in the radial direction of the cover plate 40, so that the support bosses 44 are arranged by fully utilizing the space of the non-explosion-proof area 42, the abutting structure of the cover plate 40 and the collecting plate 30 is more stable and reliable, and the rigidity of the cover plate 40 can be better enhanced.

Optionally, each support boss 44 includes a plurality of sub-segments 441, the respective sub-segments 441 of each support boss 44 being commonly spaced around the explosion-proof area 41. In this way, by designing each support boss 44 as a plurality of sub-sections 441 surrounding the explosion-proof area 41 with a gap between two adjacent sub-sections 441, it is advantageous to eliminate residual stress generated when the support boss 44 is press-molded on the cover plate 40.

Further, in any one set of adjacent two support bosses 44, each sub-section 441 of one support boss 44 is arranged offset from each sub-section 441 of the other support boss 44 in the radial direction of the cover plate 40. That is, in any adjacent two support bosses 44, any one subsection 441 of one support boss 44 is opposed to a gap between the two subsections 441 of the other support boss 44.

In particular to the embodiment shown in fig. 2, the number of support bosses 44 of the non-explosion-proof area 42 of the cover plate 40 is two, both support bosses 44 being arranged around the explosion-proof area 41. For convenience of description, one support boss 44 closer to the explosion-proof area 41 is named as an inner-ring support boss 44a, and one support boss 44 farther from the explosion-proof area 41 is named as an outer-ring support boss 44b. The inner race support ledge 44a includes four subsections 441 and the outer race support ledge 44b also includes four subsections 441. Four gaps are formed between the four subsections 441 of the outer race support boss 44b. In the radial direction of the cover plate 40, four sub-sections 441 of the inner ring support boss 44a are opposed to four gaps formed between the four sub-sections 441 of the outer ring support boss 44b, respectively. Therefore, each subsection can better strengthen the rigidity of the cover plate, and deformation of the cover plate caused by residual stress is avoided.

In an embodiment of the present utility model, the cell assembly 20 is composed of a positive electrode sheet, a negative electrode sheet, and an isolating film. The battery cell mainly relies on metal ions to move between the positive pole piece and the negative pole piece to work. The positive electrode plate comprises a positive electrode current collector and a positive electrode active material layer, wherein the positive electrode active material layer is coated on the surface of the positive electrode current collector, the positive electrode current collector without the positive electrode active material layer protrudes out of the positive electrode current collector coated with the positive electrode active material layer, and the positive electrode current collector without the positive electrode active material layer is used as a positive electrode lug. Taking a lithium ion battery as an example, the material of the positive electrode current collector may be aluminum, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate or the like. The negative electrode plate comprises a negative electrode current collector and a negative electrode active material layer, wherein the negative electrode active material layer is coated on the surface of the negative electrode current collector, the negative electrode current collector without the negative electrode active material layer protrudes out of the negative electrode current collector coated with the negative electrode active material layer, and the negative electrode current collector without the negative electrode active material layer is used as a negative electrode tab. The material of the negative electrode current collector may be copper, and the negative electrode active material may be carbon, silicon, or the like. The material of the separator may be polypropylene (PP) or Polyethylene (PE). In addition, the cell assembly 20 may be a winding type structure or a lamination type structure, and the embodiment of the present utility model is not limited thereto.

Alternatively, the material of the case 10 and the cover 40 may be steel. The material of the current collecting plate 30 may be copper, and the outer surface of the current collecting plate 30 has a nickel plating layer. Of course, in other embodiments, other conductive materials may be used for the housing 10, the cover plate 40, and the current collecting plate 30, which are not limited herein.

Specifically, the battery cell further includes an electrode terminal 50 (see fig. 1), and the electrode terminal 50 is disposed on the case 10 in an insulating manner and electrically connected to the cell assembly 20, so that the electrode terminal 50 serves as another electrode of the battery cell and has a polarity opposite to that of the case 10, i.e., the electrode terminal 50 and the case 10 together serve as positive and negative two stages of the battery cell to achieve power input or output of the battery cell.

Optionally, the current collecting plate 30 is electrically connected to the negative electrode tab of the cell assembly 20, so that the housing 10 is the negative electrode of the battery cell. The electrode terminal 50 is electrically connected with the positive electrode tab of the cell assembly 20 such that the electrode terminal 50 serves as the positive electrode of the battery cell. Of course, in other embodiments, the case 10 may also be used as a positive electrode of a battery cell, and the electrode terminal 50 may be used as a negative electrode of the battery cell, which is not limited herein. The assembly structure of the electrode terminal 50 and the case 10 may be a well-known structure, and is not limited thereto.

Based on the battery, the utility model further provides electric equipment. The powered device includes a battery or battery cell as described in any of the embodiments above, with the powered device utilizing the battery or battery cell as a power source. In particular, the electrical consumer may be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy, an electric tool, and the like. The vehicle can be a fuel oil vehicle, a fuel gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle or a range-extended vehicle; spacecraft including airplanes, rockets, space planes, spacecraft, and the like; the electric toy includes fixed or mobile electric toys, such as a game machine, an electric car toy, an electric ship toy, and an electric airplane toy; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railroad power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete shakers, and electric planers, among others. The embodiment of the utility model does not limit the electric equipment in particular.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples illustrate only a few embodiments of the utility model, which are described in detail and are not to be construed as limiting the scope of the utility model. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the utility model, which are all within the scope of the utility model. Accordingly, the scope of protection of the present utility model is to be determined by the appended claims.

Claims (11)

1. The utility model provides a apron, its characterized in that includes explosion-proof district (41) and around non-explosion-proof district (42) that explosion-proof district (41) laid, explosion-proof nick (43) have been seted up in explosion-proof district (41), non-explosion-proof district (42) be provided with protrusion in support boss (44) of one side surface of apron (40), apron (40) are used for through support boss (44) and current collecting tray (30) butt.

2. The cover plate according to claim 1, wherein the cover plate (40) further has a first side (a 1) and a second side (a 2) opposite to each other, the support boss (44) protruding from a surface of the first side (a 1) of the cover plate (40);

the explosion-proof area (41) is arranged from the second side (a 2) of the cover plate (40) to the first side (a 1) in a protruding mode, and the height of the explosion-proof area (41) protruding out of the surface of the first side (a 1) is lower than the height of the supporting boss (44) protruding out of the surface of the first side (a 1).

3. Cover plate according to claim 2, wherein the difference between the height of the explosion-proof area (41) protruding from the surface of the first side (a 1) and the height of the support boss (44) protruding from the surface of the first side (a 1) is 0.2mm to 0.8mm.

4. A cover plate according to any one of claims 1 to 3, wherein the support boss (44) is annular in shape arranged around the explosion-proof area (41).

5. The cover plate according to claim 4, wherein the support bosses (44) comprise at least two, at least two of the support bosses (44) each being arranged around the explosion-proof area (41) and being spaced from each other in a radial direction of the cover plate (40).

6. The cover plate of claim 5, wherein each of said support bosses (44) includes a plurality of sub-segments (441), the respective sub-segments (441) of each of said support bosses (44) being spaced apart around said explosion-proof area (41).

7. The cover plate according to claim 6, wherein in any one set of two adjacent support bosses (44), each of the subsections (441) of one of the support bosses (44) is arranged offset from each of the subsections (441) of the other support boss (44) in the radial direction of the cover plate (40).

8. A cover plate according to any one of claims 1 to 3, wherein the cover plate (40) further has a first side (a 1) and a second side (a 2) opposite each other, a portion of the non-explosion-proof area (42) protruding outwardly from the second side (a 2) towards the first side (a 1) to form a recess in the second side (a 2) and the support boss (44) in the first side (a 1).

9. A battery cell, comprising:

a housing (10) having an opening (11);

a battery cell assembly (20) housed in the housing (10);

a current collecting plate (30) accommodated in the shell (10) and positioned at one side of the battery cell assembly (20) facing the opening (11);

cover plate (40) according to any one of claims 1 to 8, sealingly arranged at the opening (11) of the housing (10) and abutting the collecting tray (30) through the support boss (44).

10. A battery comprising the battery cell of claim 9.

11. A powered device comprising a battery cell as defined in claim 9 or a battery cell as defined in claim 10.