CN221176452U - Single battery, battery pack and power utilization system - Google Patents

Abstract

The application discloses a single battery, a battery pack and an electric system, and belongs to the technical field of batteries. Comprising the following steps: the shell is provided with a containing cavity for containing the battery cell, and the containing cavity is provided with an opening; the cover body is provided with a limit groove on one surface close to the accommodating cavity, at least part of the shell is arranged in the limit groove, and a connecting space is formed between the outer wall of the shell, which is away from the accommodating cavity, and the inner wall of the limit groove, which is towards the accommodating cavity; and the melting piece is positioned in the connecting space and is used for sealing and connecting the shell and the cover body, so that the cover body seals the opening of the accommodating cavity. The shell and the cover body which are clamped with each other through the limiting groove have the beneficial effect of improving the connection strength between the cover body and the shell. After placing the fusion piece in the connecting space, melt the fusion piece through laser and weld casing and lid, laser melts the fusion piece into fluid, and the fluid flows in the fit clearance department of casing and lid in the spacing groove, has the beneficial effect that improves welding uniformity and battery cell structural strength.

Description

Single battery, battery pack and power utilization system

Technical Field

The application belongs to the technical field of batteries, and particularly relates to a single battery, a battery pack and an electric system.

Background

The functional device for providing kinetic energy for the new energy automobile is a battery pack, wherein the battery pack is formed by combining a plurality of battery monomers, and the weight of the battery monomers influences the weight of the battery pack.

In the prior art, in order to meet the light weight index requirements of the automobile industry and reduce the weight of a battery pack, a battery monomer outer shell body starts to adopt thinner and lighter aluminum or steel materials. In the actual welding process, the cover body is directly covered on the shell and is welded and connected.

However, in the welding process, the cover body and the housing are deformed by the thermal stress, so that the connection strength of the cover body and the housing is low, and the formed welding consistency is poor (low yield and poor penetration consistency), thereby affecting the welding quality, the welding appearance and the tightness of the battery cell.

Disclosure of utility model

The embodiment of the application aims to provide a single battery, a battery pack and an electric system, which can solve the problem of poor welding consistency of the single battery in the prior art.

In order to solve the technical problems, the application is realized as follows:

In a first aspect, embodiments of the present application provide a single battery, including a housing having a housing cavity for housing a battery cell, the housing cavity having an opening; the cover body is provided with a limit groove on one surface close to the accommodating cavity, at least part of the shell is arranged in the limit groove, and a connecting space is formed between the outer wall of the shell, which is away from the accommodating cavity, and the inner wall of the limit groove, which is towards the accommodating cavity; and the melting piece is positioned in the connecting space and is used for sealing and connecting the shell and the cover body, so that the cover body seals the opening of the accommodating cavity.

In an embodiment of the application, the housing forms a receiving cavity, which is arranged to receive the battery cell. The shell is also provided with an opening, and the shell is used for being matched with the cover body and mutually connected with the cover body through laser brazing so as to seal the opening, so that a sealed placing space is provided for the battery cell to protect the battery cell. The spacing groove has been seted up to the one side that the lid is close to holding the chamber, and at least part casing sets up in the spacing inslot in order to realize the cooperation between lid and the casing, and wherein, the casing joint has the connection space after the spacing groove, and the casing deviates from and holds the outer wall in chamber and the spacing groove orientation holds between the inner wall in chamber. The arrangement of the connecting space is used for providing a placing space for the fusion piece during welding. In practical application, before welding casing and lid, earlier with casing joint in the spacing groove, casing and lid through spacing groove mutual joint have the beneficial effect that improves joint strength between lid and the casing, have also improved the welding stability between lid and the casing for subsequent welding. Then, after placing the melting piece in the connecting space again, melt the melting piece through laser and weld casing and lid, laser melts the melting piece into fluid, and the fluid flows in the fit clearance department of casing and lid in the spacing groove, and wherein, the melting piece mobility is good, and the filling performance to the connecting space is good, and the setting of spacing groove has carried out the restriction of certain degree to the fluid flow position for weld seam penetration uniformity after the welding is accomplished is higher, and welding quality is good, has the beneficial effect that improves welding uniformity, and then has still improved single battery structural strength's beneficial effect.

The application adopts the laser brazing welding technology to weld the shell and the cover body, and compared with the laser welding, the laser brazing has the advantages of low welding power and no welding slag basically. Therefore, the laser welding has an advantageous effect of reducing welding defects generated due to welding spatter.

It should be noted that the laser brazing has flexible requirements on the laser position, the laser light emitting device can be opposite to the center position of the melting piece, a certain angle exists between the laser light emitting device and the center position of the melting piece, the design and manufacturing difficulty of the welding equipment platform can be reduced, and the space of the welding equipment platform can be saved.

In a second aspect, embodiments of the present application provide a battery pack including a single battery as described above.

In the battery pack with the single battery, the connection between the cover body and the shell is realized by arranging the limiting groove and the protruding part with the inclined side wall and adopting the laser brazing process, so that the welding consistency of the single battery is improved, the tightness of the single battery is improved, and the matching tolerance of the cover body and the shell is reduced.

In a third aspect, embodiments of the present application also provide an electrical system comprising a battery pack as described above or a single battery as described above.

In the embodiment of the present application, the power consumption system may be an energy storage device or a vehicle, which is not limited in this embodiment.

Drawings

Fig. 1 is a schematic structural view of a single battery according to an embodiment of the present application;

Fig. 2 is a schematic diagram of a front view structure of a single battery according to an embodiment of the present application;

FIG. 3 is a schematic side view of a cell in an embodiment of the application;

FIG. 4 is a schematic cross-sectional view of a connection between a cover and a housing according to an embodiment of the present application;

fig. 5 is an enlarged schematic view of the structure a in fig. 4 according to an embodiment of the present application.

Reference numerals illustrate:

10. a housing; 20. a cover body; 21. a limit groove; 22. a boss; 23. coaming plate; x, first direction.

Detailed Description

The following description of the embodiments of the present application will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are some, but not all embodiments of the application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

The terms first, second and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged, as appropriate, such that embodiments of the present application may be implemented in sequences other than those illustrated or described herein, and that the objects identified by "first," "second," etc. are generally of a type, and are not limited to the number of objects, such as the first object may be one or more. Furthermore, in the description and claims, "and/or" means at least one of the connected objects, and the character "/", generally means that the associated object is an "or" relationship.

The unit cell, the battery pack and the power utilization system provided by the embodiment of the application are described in detail below through specific embodiments and application scenes thereof with reference to the accompanying drawings.

Referring to fig. 1 to 5, an embodiment of the present application provides a battery cell including a case 10, the case 10 having a receiving cavity for receiving a battery cell, the receiving cavity having an opening; the cover body 20, one side of the cover body 20 close to the accommodating cavity is provided with a limit groove 21, at least part of the shell 10 is arranged in the limit groove 21, and a connecting space is reserved between the outer wall of the shell 10, which is away from the accommodating cavity, and the inner wall of the limit groove 21, which is towards the accommodating cavity; and a fusing member disposed in the connection space and sealing-connecting the case 10 and the cover 20 such that the cover 20 seals the receiving chamber opening.

In an embodiment of the application, the housing 10 forms a receiving chamber arranged to receive the battery cell. The housing 10 also has an opening, and the housing 10 is configured to cooperate with the cover 20 and to seal the opening by being connected to each other by laser brazing to provide a sealed placement space for the cells to protect the cells. The spacing groove 21 has been seted up to the one side that lid 20 is close to the chamber of holding, and at least part casing 10 sets up in spacing groove 21 in order to realize the cooperation between lid 20 and the casing 10, and wherein, casing 10 joint is after spacing groove 21, and the casing 10 deviates from the outer wall that holds the chamber and spacing groove 21 has the connection space towards holding between the inner wall in chamber. The arrangement of the connecting space is used for providing a placing space for the fusion piece during welding. In practical application, before welding the shell 10 and the cover 20, the shell 10 is clamped in the limiting groove 21, and the shell 10 and the cover 20 clamped with each other through the limiting groove 21 have the beneficial effect of improving the connection strength between the cover 20 and the shell 10, and also improve the welding stability between the cover 20 and the shell 10 for subsequent welding. Then, after placing the fusion piece in the connecting space again, melt the fusion piece through laser and weld casing 10 and lid 20, laser melts the fusion piece into fluid, the fluid flows in the cooperation clearance department of casing 10 and lid 20 in spacing groove 21, wherein, the fusion piece mobility is good, the filling performance to the connecting space is good, and the setting of spacing groove 21 has carried out the restriction of certain degree to the flow position of fluid, make the welding seam penetration uniformity after the welding is accomplished higher, welding quality is good, have the beneficial effect that improves the welding uniformity, and then still improved the beneficial effect of monomer battery structural strength.

It should be noted that, the present application adopts the laser brazing welding technique to weld the case 10 and the cover 20, and laser brazing has advantages of low welding power and substantially no slag generation compared with laser welding. Therefore, the laser welding has an advantageous effect of reducing welding defects generated due to welding spatter.

It should be noted that the laser brazing has flexible requirements on the laser position, the laser light-emitting position can be opposite to the center position of the melting piece, a certain angle exists between the laser light-emitting position and the center position of the melting piece, the design and manufacturing difficulty of the welding equipment platform can be reduced, and the space of the welding equipment platform can be saved.

In addition, it should be noted that, in the embodiment of the present application, the shell 10 and the cover 20 are connected only by melting the melting member, so that the melting member melts at a temperature relatively lower than that of directly welding the shell 10 and the cover 20, thereby reducing the thermal stress between the shell 10 and the cover 20 and improving the consistency of welding.

In addition, in the embodiment of the present application, the molten member is formed by melting the brazing material filled in the joint space. In general, the brazing material is selected to have a melting point lower than that of the material of the cover 20 and that of the material of the housing 20, and may be in the form of a block, a bar, a ring, or the like.

In the embodiment of the present application, the case 10 may be made of aluminum or an aluminum alloy, or may be made of steel, and the present application is not limited thereto.

Alternatively, in the embodiment of the present application, the limiting groove 21 is an annular groove that is connected end to end and penetrates, and at least part of the housing 10 is located in the annular groove.

In the embodiment of the present application, it can be understood that the annular grooves that are connected end to end and pass through are closed grooves, and the closed grooves have higher stability, and can provide clamping positions for the housing 10 in a circle around the housing 10. In the embodiment of the application, the annular groove encircling the circumference of the shell 10 is arranged to realize the clamping connection with the shell 10 from the outer circumference of the shell 10, so that the connecting strength and the connecting stability between the shell 10 and the cover 20 are improved.

Optionally, in the embodiment of the present application, the cover 20 includes a substrate, a coaming 23 and a protruding portion 22, the protruding portion 22 is disposed on a surface of the substrate near the accommodating cavity, the coaming 23 is disposed on an outer periphery of the substrate, and the coaming 23 and the protruding portion 22 are disposed opposite to each other, where the substrate, the coaming 23 and the protruding portion 22 jointly enclose to form a limiting groove 21; the casing 10 is connected to the limiting groove 21 through a melting piece, and the casing 10 is sleeved on the periphery of the protruding portion 22 and is abutted against part of the protruding portion 22.

In the embodiment of the present application, the protruding portion 22 is provided to provide a certain supporting and limiting effect for the housing 10 when the housing 10 and the cover 20 are matched, and the protruding portion 22 is provided to block laser during the welding process, so as to avoid the damage of the laser during the welding to the battery cell. Specifically, the boss 22 is disposed on a side of the base plate close to the accommodating chamber, the coaming 23 is disposed on an outer periphery of the base plate, and the coaming 23 and the boss 22 are disposed opposite to each other. Wherein, the base plate, the coaming plate 23 and the protruding part 22 jointly enclose to form a limit groove 21. It can be understood that the protruding portion 22 is disposed inside the limiting groove 21, and the limiting groove 21 is formed on the periphery of the protruding portion 22. In practical application, the casing 10 is sleeved on the periphery of the boss 22 and is clamped with the limiting groove 21. The protruding portion 22 extends in a direction approaching the battery cell, when the housing 10 and the cover 20 are assembled, the housing 10 is clamped in a limit groove 21 formed by the joint of the base plate, the coaming 23 and the protruding portion 22, and the housing 10 is sleeved on the periphery of the protruding portion 22 and is abutted against part of the protruding portion 22. Specifically, the position of the housing 10 is not shifted by the limiting action of the limiting groove 21. Further, the melting member is located in the connecting space, and the connection between the case 10 and the cover 20 is achieved by laser brazing.

Alternatively, in the embodiment of the present application, the gap between the inner wall of the housing 10 toward the accommodation chamber and the outer wall of the boss 22 toward the shroud 23 gradually decreases in the first direction X; the first direction X is a direction perpendicular to the opening. The gap between the inner wall of the housing 10 facing the accommodating chamber and the outer wall of the boss 22 facing the shroud 23 is the distance between two points on the same horizontal line along the opposite direction of the shroud 23 to the boss 22, where the inner wall of the housing 10 facing the accommodating chamber and the outer wall of the boss 22 facing the shroud 23.

In the embodiment of the present application, in one case, the outer wall of the boss 22 is a slope, the inner wall of the housing 10 facing the accommodation chamber is a vertical surface, and the gap between the slope as the outer wall and the vertical surface as the inner wall in the first direction X is gradually increased. In another case, the outer wall of the boss 22 is a vertical surface, the inner wall of the housing 10 facing the accommodating chamber is a slope, and a gap between the slope as the inner wall and the vertical surface as the outer wall is gradually increased in the first direction X.

Further, in the above two cases, the gap between the inner wall of the housing 10 facing the accommodating cavity and the outer wall of the boss 22 facing the coaming 23 gradually decreases along the first direction X, and the setting of the gap provides a certain accommodating space for the cooperation between the housing 10 and the cover 20, thereby reducing the required cooperation tolerance between the housing 10 and the cover 20, and having the beneficial effects of reducing the manufacturing process difficulty of the housing 10 and the cover 20 and the cooperation requirement between the cover 20 and the housing 10.

Alternatively, in the embodiment of the present application, the convex portion 22 is provided obliquely toward the outer wall of the shroud 23, and the orthographic projection area of the convex portion 22 in the first direction X is gradually increased in the first direction X; the first direction X is a direction perpendicular to the opening. In the embodiment of the application, the outer wall is obliquely arranged, so that a certain included angle is formed between the outer wall and the first direction X. Specifically, the projection 22 has a gradually increasing forward projection area along the first direction X, that is, the projection 22 has a gradually increasing peripheral shape along the first direction X. In practice, in order to reduce the space occupied by the battery cells, the surface of the casing of the battery cells is typically a vertical plane along the first direction X. It will be appreciated that the vertical faces of the cells and the outer walls of the obliquely arranged bosses 22 are naturally also spaced apart. Since the outer periphery of the boss 22 is gradually increased in the first direction X, the interval between the outer wall and the case 10 is gradually decreased in the first direction X. In the embodiment of the application, the arrangement of the space formed between the outer wall of the inclined arrangement and the first direction X provides a certain accommodating space for the cooperation between the housing 10 and the cover 20, which has the beneficial effect of having low requirements on the dimensional tolerance of the material fed from the housing 10 and the cover 20, and is more beneficial to the clamping connection between the housing 10 and the limiting groove 21.

Alternatively, in an embodiment of the present application, the projection 22 has a predetermined angle alpha between the plane of the outer wall of the shroud 23 and the plane of the inner wall of the housing 10 facing the receiving chamber, and 2 DEG alpha is less than or equal to 15 deg.

In the embodiment of the application, the included angle between the protruding part 22 and the housing 10 is a preset included angle between the outer wall of the protruding part 22 facing the coaming 23 and the inner wall of the housing 10 facing the accommodating cavity, and when the housing 10 and the cover 20 are matched, the preset included angle has the beneficial effect of facilitating the clamping connection of the housing 10 and the limiting groove 21. In practical applications, the material of the housing 10 is generally aluminum or steel, and in order to reduce the space occupied by the unit cells, the thickness of the housing 10 is generally about 0.05mm to 0.25mm. According to the thickness of the housing 10, limiting the range of the preset included angle to be 2 degrees or more and 15 degrees or less does not affect the strength of the single battery housing 10, and has the beneficial effect of facilitating the cooperation of the housing 10 and the cover 20.

Further, the setting of the preset angle can also be used for realizing the matching action between the shell 10 and the cover 20 through an automation device, and has the beneficial effect of improving the automation degree of the manufacturing process.

In the embodiment of the application, the thickness of the shell 10 is D, wherein D is more than or equal to 0.05mm and less than or equal to 0.25mm. The shell thickness in the range can reduce the cost and improve the energy density of the single battery. And the cover 20 is connected with the housing 10 by brazing because the housing 10 is thin.

In the embodiment of the application, the thickness of the shell 10 is D, and the distance a from any position of the protruding part 22 facing the outer wall of the coaming 23 to the surface of the coaming 23 facing the protruding part 22 is 0.1 D.ltoreq.a.ltoreq.0.3D.

Further, in the embodiment of the application, the distance a from any position of the boss 22 toward the outer wall of the shroud 23 to the surface of the shroud 23 facing the boss 22 is 0.05 mm.ltoreq.a.ltoreq.0.1 mm.

In the embodiment of the present application, the arrangement of the connection space provides the placement space and the filling width for the molten part on the one hand, and the fit clearance between the case 10 and the cover 20 on the other hand, so that the effect of reducing the dimensional tolerance of the materials fed from the case 10 and the cover 20 and the effect of reducing the fit tolerance between the case 10 and the cover 20 is achieved. In the embodiment of the application, the width of the connecting space a is set to be in the range of 0.1D or more and 0.3D or less, so that the above-described advantageous effects of preventing the melting member and reducing the tolerance can be achieved.

In the embodiment of the application, the thickness of the coaming 23 along the extending direction of the base plate is b, wherein, D is less than or equal to b and less than or equal to 2D.

In the embodiment of the application, the thickness of the coaming plate 23 along the extending direction of the base plate is b, and b is more than or equal to 0.05mm and less than or equal to 0.15mm.

In the embodiment of the application, in actual welding, the position of the coaming 23 is a laser heating position, and the width dimension of the coaming 23 has a certain influence on the input of laser energy, so that the welding quality is affected. Setting the thickness of the coaming 23 to be in the range of the thickness of the shell 10 being greater than or equal to the thickness of the shell 10 and less than or equal to twice the thickness of the shell 10 has the beneficial effect of better utilizing laser energy and further improving welding quality.

It should be noted that the requirement of the improved laser brazing on the laser position is more flexible, the external laser light can directly face the center position of the melting piece, and a certain angle exists between the external laser light and the center position of the melting piece, the embodiment is not limited in this way, and the welding quality is not affected by the change of the laser position.

In the embodiment of the application, the coaming 23 has a first preset height along the first direction X, wherein the first preset height is c, and c is more than or equal to 0.5D and less than or equal to 1.5D.

In the embodiment of the application, the coaming 23 has a first preset height along the first direction X, wherein the first preset height is c, and c is more than or equal to 0.05mm and less than or equal to 0.2mm.

In the embodiment of the present application, the height of the coaming 23 has a limiting effect on the position of the housing 10, so that the connection strength of the housing 10 and the cover 20 when being matched is improved. On the other hand, the device also has the function of limiting the melting piece, and is embodied before and after laser welding. Setting the height of the apron 23 to be in the range of 0.5D or more and 1.5D or less, the apron 23 having a certain height has the function of preventing the molten metal from coming out of the stopper groove 21 before laser welding, and in laser welding, the apron 23 having a certain height has the function of preventing the molten metal from running off.

Alternatively, in the embodiment of the present application, the coaming 23 has a first preset height along the first direction X, the first preset height is c, and the boss 22 has a second preset height along the first direction X, the second preset height is h, where h is greater than or equal to c.

In the embodiment of the present application, the protruding portion 22 with the second preset height may provide a certain support for the housing 10 along the outer circumference of the protruding portion 22, and meanwhile, the limiting groove 21 cooperates with the protruding portion 22 with the second preset height to fix the position of the housing 10 to a certain extent. Setting the second preset height to be within a range where the depth of the limit groove 21 in the first direction X is equal to or greater has the advantage of preventing the housing 10 from being inclined toward the boss 22 to cause unstable fit between the housing 10 and the cover 20.

Alternatively, in an embodiment of the present application, there is provided a battery pack including the unit cells as described above.

In the embodiment of the application, the battery pack with the single battery has the beneficial effects that the connection between the cover body 20 and the shell 10 is realized by adopting a laser brazing process through the arrangement of the limiting groove 21 and the protruding part 22 with the inclined side wall, so that the welding consistency of the single battery is improved, the tightness of the single battery is improved, and the matching tolerance of the cover body 20 and the shell 10 is reduced.

It should be noted that, the battery cell further includes a cover spacer, a cover pull-out piece, a pole assembly, and other structural members, where the cover spacer abuts against one end of the boss 22 near the battery cell, the explosion-proof valve heat dissipation hole is opened in the cover spacer, the cover pull-out piece is disposed at one end of the cover spacer near the battery cell, and covers part of the cover spacer. The post assembly extends from the cover tab through the cover 20 in a first direction X and at least partially protrudes out of the outer surface of the cover 20. In practical application, the cover 20 and the housing 10 are connected by laser brazing, specifically, the battery cell is put into the accommodating cavity of the housing 10 from the opening, and then the cover 20 is covered on the housing 10, at this time, the cover 20 and the housing 10 are mutually matched, and a certain included angle is formed between the outer wall of the protruding portion 22 and the inner wall of the housing 10, so that the matching tolerance of the cover 20 and the housing 10 is reduced. At least part of the housing 10 is placed in the limiting groove 21, a connecting space is provided between the outer wall of the housing 10 facing away from the receiving chamber and the inner wall of the limiting groove 21 facing toward the receiving chamber, and a melting part is placed in the connecting space to wait for welding. The case 10 face and the cover 20 face are pressed by a tool to fix the positions of the case 10 and the cover 20, and a laser melts a molten material placed in a connecting space to complete welding of the case 10 and the cover 20.

Optionally, in an embodiment of the present application, there is also provided an electrical system comprising a battery pack as described above or a single battery as described above.

In the embodiment of the present application, the power consumption system may be an energy storage device or a vehicle, which is not limited in this embodiment.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element. Furthermore, it should be noted that the scope of the methods and apparatus in the embodiments of the present application is not limited to performing the functions in the order shown or discussed, but may also include performing the functions in a substantially simultaneous manner or in an opposite order depending on the functions involved, e.g., the described methods may be performed in an order different from that described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

The embodiments of the present application have been described above with reference to the accompanying drawings, but the present application is not limited to the above-described embodiments, which are merely illustrative and not restrictive, and many forms may be made by those having ordinary skill in the art without departing from the spirit of the present application and the scope of the claims, which are to be protected by the present application.

Claims (13)

1. A single cell, characterized by comprising:

A housing (10), the housing (10) having a receiving chamber for receiving a battery cell, the receiving chamber having an opening;

The cover body (20), one side of the cover body (20) close to the accommodating cavity is provided with a limit groove (21), at least part of the shell (10) is arranged in the limit groove (21), and a connecting space is reserved between the outer wall of the shell (10) deviating from the accommodating cavity and the inner wall of the limit groove (21) facing the accommodating cavity;

And the melting piece is positioned in the connecting space and is used for sealing and connecting the shell (10) and the cover body (20), so that the cover body (20) seals the opening of the accommodating cavity.

2. The unit cell according to claim 1, characterized in that the limiting groove (21) is an annular groove, at least part of the housing (10) being located in the annular groove.

3. The unit cell according to any one of claims 1 or 2, wherein the cover body (20) comprises a base plate, a surrounding plate (23) and a protruding portion (22), the protruding portion (22) is arranged on one surface of the base plate, which is close to the accommodating cavity, the surrounding plate (23) is arranged on the periphery of the base plate, and the base plate, the surrounding plate (23) and the protruding portion (22) jointly enclose to form the limit groove (21);

The shell (10) is connected to the limiting groove (21) through the melting piece, and the shell (10) is sleeved on the periphery of the protruding portion (22) and is abutted to part of the protruding portion (22).

4. A single cell according to claim 3, the gap between the housing (10) towards the inner wall of the receiving cavity and the boss (22) towards the outer wall of the shroud (23) decreasing gradually in a first direction (X);

Wherein the first direction (X) is a direction perpendicular to the opening.

5. A cell according to claim 3, wherein the protrusions (22) are arranged obliquely towards the outer wall of the shroud (23), the orthographic projection area of the protrusions (22) along a first direction (X) increasing gradually along the first direction (X);

Wherein the first direction (X) is a direction perpendicular to the opening.

6. A single cell according to any one of claims 4 or 5, wherein the projection (22) has a predetermined angle α between the plane of the outer wall of the enclosure (23) and the plane of the inner wall of the housing (10) towards the receiving chamber, and 2 ° - α -15 °.

7. A cell according to claim 3, wherein the thickness of the case (10) is D, and the distance from any position of the boss (22) facing the outer wall of the shroud (23) to the surface of the shroud (23) facing the boss (22) is a, wherein 0.1 d.ltoreq.a.ltoreq.0.3D.

8. A unit cell according to claim 3, wherein the thickness of the casing (10) is D, and the thickness of the shroud (23) in the direction in which the substrate extends is b, wherein d.ltoreq.b.ltoreq.2d.

9. A cell according to claim 3, wherein the thickness of the housing (10) is D, and the shroud (23) has a first predetermined height in a first direction, the first predetermined height being c, wherein 0.5D is less than or equal to c is less than or equal to 1.5D.

10. A cell according to claim 3, wherein the shroud (23) has a first predetermined height in a first direction, the first predetermined height being c _, and the boss (22) has a second predetermined height in the first direction, the second predetermined height being h, wherein h is equal to or greater than c.

11. A cell according to claim 3, wherein the thickness of the housing (10) is D, wherein 0.05mm +.d +.0.25 mm.

12. A battery pack comprising the single battery according to any one of claims 1 to 11.

13. An electrical system comprising a battery pack according to claim 12 or a cell according to any one of claims 1 to 11.