Battery and electric equipment

Abstract

The utility model discloses a battery which comprises a shell, a top cover and a battery cell arranged in a closed space defined by the shell and the top cover, the shell comprises a bottom plate opposite to the top cover; a through mounting hole is formed in the bottom plate, and an anti-explosion valve is arranged in the mounting hole; gummed paper is arranged on the inner surface of the bottom plate; in a section perpendicular to the first direction, the projection of the gummed paper completely covers the projection of the mounting hole; the first direction is parallel to the direction from the top cover to the bottom plate. The explosion-proof valve is arranged on the bottom plate of the shell, the space distribution of all parts on the top of the shell is more reasonable, no hole needs to be formed in the top cover to install the explosion-proof valve, and the machining difficulty of the top cover is reduced; according to the explosion-proof valve, the gummed paper is adhered to the inner surface of the bottom plate, the gummed paper is opposite to the mounting hole for mounting the explosion-proof valve, and the area of the gummed paper is larger than that of the mounting hole, so that the gummed paper completely covers the mounting hole, electrolyte can be effectively prevented from corroding the explosion-proof valve and a connecting gap between the explosion-proof valve and the mounting hole, the explosion-proof valve can be protected, and the stability of the explosion value of the explosion-proof valve is improved.

Description

Technical Field

[0001] The present application relates to the technical field of lithium-ion batteries, and more specifically to a battery, and also to an electrical device including the battery. Background Art

[0002] When the battery fails abnormally and the pressure inside the battery increases to a certain level, the explosion-proof valve will rupture, exhausting gas and liquid, thereby preventing the battery from exploding. The explosion-proof valve of traditional batteries is often set on the top cover, which increases the difficulty of processing the top cover and reduces the structural strength of the top cover. Utility Model Content

[0003] In view of this, the present application provides a battery and also provides an electrical device including the above-mentioned battery, which solves the problems of difficult top cover processing and low structural strength.

[0004] In order to achieve the above objectives, this application provides the following technical solutions:

[0005] A battery comprises a shell, a top cover, and a battery cell arranged in a closed space enclosed by the shell and the top cover; the shell comprises a bottom plate opposite to the top cover;

[0006] The bottom plate is provided with a through installation hole, and an explosion-proof valve is arranged in the installation hole; the inner surface of the bottom plate is provided with adhesive tape;

[0007] In a cross section perpendicular to a first direction, a projection of the adhesive tape completely covers a projection of the mounting hole; the first direction is parallel to a direction from the top cover to the bottom plate.

[0008] Optionally, in the above battery, in a cross section perpendicular to the first direction, the projection area of ​​the adhesive tape is S1, the projection area of ​​the mounting hole is S2, and the projection area of ​​the inner surface of the bottom plate is S3, and S1, S2, and S3 satisfy:

[0009] 1.2≤S1 / S2≤5;

[0010] S1<S3.

[0011] Optionally, in the above battery, the battery cell includes a plurality of bare battery cells;

[0012] The explosion-proof valve has a first area; in a cross section perpendicular to the first direction, the projected area of ​​all the bare cells is S4, the projected area of ​​the first area is S5, and S4 and S5 satisfy:

[0013] 3≤S4 / S5≤10.

[0014] Optionally, in the above battery, the outer surface of the bare cell is covered with a Mylar film;

[0015] The inner surface of the bottom plate is provided with a bottom support plate;

[0016] The bottom support plate is provided with a first through hole, and the side surface of the Mylar film opposite to the bottom support plate is provided with a second through hole, and the first through hole is connected to the second through hole.

[0017] Optionally, in the above battery, an extension length of the first through hole and an extension length of the second through hole are parallel to the first direction;

[0018] In a cross section perpendicular to the first direction, the mounting hole has a first projection, the area of ​​the first projection is S2, and the sum of the projection areas of the plurality of first through holes located in the first projection is S6; S2 and S6 satisfy:

[0019] 1.5≤S2 / S6≤5.

[0020] Optionally, in the above battery, the mounting hole is a stepped hole, the stepped hole has a plurality of hole segments, wherein the first hole segment close to the outer surface of the bottom plate has the largest hole diameter, and a stepped surface is formed at the junction of the first hole segment and the adjacent hole segment;

[0021] The explosion-proof valve is fixedly arranged on the step surface, and the explosion-proof valve does not protrude from the outer surface of the bottom plate.

[0022] Optionally, in the above battery, the explosion-proof valve includes a middle area and an edge area arranged around the middle area, and the edge area is at least partially fixedly arranged on the step surface;

[0023] Along the first direction, the thickness of the edge region is h, the depth of the first hole segment is a, and h and a satisfy:

[0024] 0.05mm≤ah≤2mm.

[0025] Optionally, in the above battery, the battery cell comprises a plurality of bare battery cells, the bare battery cell comprises a pole piece, and the pole piece comprises a current collector and a pole ear connected to the current collector;

[0026] Along the first direction, the electrode tab includes a first portion and a second portion, and the first portion is close to the current collector.

[0027] Optionally, in the above battery, the first portion includes a tab shoulder portion that is not connected to the second portion;

[0028] The top cover is provided with a through injection hole; in a cross section perpendicular to the first direction, the projection of the injection hole is located within the projection of the tab shoulder.

[0029] An electrical device comprises the battery cell described above.

[0030] In the battery and electrical equipment provided by the present application, the explosion-proof valve is arranged on the bottom plate of the shell, and the spatial distribution of various components on the top of the shell is more reasonable. There is no need to open a hole in the top cover to install the explosion-proof valve, the processing difficulty of the top cover is reduced, and the structural strength of the top cover is improved; further, adhesive tape is adhered to the inner surface of the bottom plate, the adhesive tape is opposite to the mounting hole for installing the explosion-proof valve, and the area of ​​the adhesive tape is larger than the area of ​​the mounting hole, so that the adhesive tape completely covers the mounting hole, which can effectively prevent the electrolyte from corroding the explosion-proof valve and the connecting gap between the explosion-proof valve and the mounting hole, can protect the explosion-proof valve and improve the stability of its explosion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0032] Figure 1 A three-dimensional diagram of a battery in this application;

[0033] Figure 2 A three-dimensional diagram of the battery in this application from another angle;

[0034] Figure 3 An exploded view of the battery in this application;

[0035] Figure 4 This is a schematic diagram of the structure of the top cover and the battery cell in this application;

[0036] Figure 5 This is a cross-sectional view of the explosion-proof valve and base plate assembly in this application.

[0037] Figure 1-Figure 5 middle:

[0038] 1. Top cover; 2. Bottom plate; 3. Explosion-proof valve; 4. Adhesive tape; 5. Mylar film; 6. Bottom support plate; 7. First through hole; 8. Tab; 9. Electrode adapter; 10. Pole;

[0039] 101, injection hole;

[0040] 201, mounting hole;

[0041] 301, middle area; 302, edge area;

[0042] 801, first part; 802, second part; 803, ear shoulder. DETAILED DESCRIPTION

[0043] The present application provides a battery and also provides an electrical device including the battery.

[0044] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0045] like Figure 1-5 As shown, a battery comprises a shell, a top cover 1, and a battery cell. The shell and the top cover 1 enclose a closed space, and the battery cell is placed in the closed space. The shell comprises a bottom plate 2 opposite to the top cover 1. The bottom plate 2 is provided with a through mounting hole 201, and an explosion-proof valve 6 is arranged in the mounting hole 201. The inner surface of the bottom plate 2 is provided with adhesive tape 4. In a cross section perpendicular to the first direction, the projection of the adhesive tape 4 completely covers the projection of the mounting hole 201. The first direction is parallel to the direction from the top cover 1 to the bottom plate 2.

[0046] Please refer to the attached Figure 3 , the first direction is attached Figure 3 The explosion-proof valve 3 is welded to the mounting hole 201. The housing is a three-dimensional structure with an opening at the top, and the top cover 1 is sealed to the top opening of the housing.

[0047] Full coverage means that the projection of the mounting hole 201 falls within the projection range of the adhesive tape 4, and the projection of the mounting hole 201 does not have an area beyond the projection of the adhesive tape 4. In the cross section perpendicular to the first direction, the projection of the adhesive tape 4 completely covers the projection of the mounting hole 201, that is, the area of ​​the adhesive tape 4 is not less than the area of ​​the mounting hole 201, and the adhesive tape 4 bonded to the inner surface of the bottom plate 2 happens to be able to completely cover the mounting hole 201.

[0048] The explosion-proof valve 3 is arranged on the bottom plate 2 of the shell, and the spatial distribution of the various components on the top of the shell is more reasonable. There is no need to open a hole on the top cover 1 to install the explosion-proof valve, so the processing difficulty of the top cover 1 is reduced, and the structural strength of the top cover 1 is improved. Furthermore, adhesive tape 4 is adhered to the inner surface of the bottom plate 2, and the adhesive tape 4 is opposite to the installation hole 201 for installing the explosion-proof valve 3, and the area of ​​the adhesive tape 4 is larger than the area of ​​the installation hole 201, so that the adhesive tape 4 completely covers the installation hole 201, which can effectively prevent the electrolyte from corroding the explosion-proof valve 3 and the connection gap between the explosion-proof valve 3 and the installation hole 201, and can protect the explosion-proof valve 3, ensure the reliable connection effect of the explosion-proof valve 3 in the installation hole 201, and improve the stability of its explosion value.

[0049] Please refer to the attached Figure 3In certain embodiments of the present application, in a cross section perpendicular to the first direction, the projection area of ​​the adhesive tape 4 is S1, the projection area of ​​the mounting hole 201 is S2, and the projection area of ​​the inner surface of the base plate 2 is S3, and S1, S2, and S3 satisfy: 1.2≤S1 / S2≤5; S1<S3.

[0050] 1.2≤S1 / S2≤5, for example, S1 / S2 can be any one of 1.2, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, and 5.

[0051] The projection area of ​​the adhesive tape 4 in the cross section perpendicular to the first direction is the area of ​​the adhesive tape 4; the projection area of ​​the mounting hole 201 in the cross section perpendicular to the first direction is the opening area of ​​the mounting hole 201; the projection area of ​​the inner surface of the base plate 2 in the cross section perpendicular to the first direction is the area of ​​the inner surface of the base plate 2.

[0052] As can be seen from the above, the area of ​​the adhesive tape 4 is larger than the area of ​​the mounting hole 201, and the ratio of the two is between 1.2-5, which can ensure that the adhesive tape 4 has a sufficiently large size to ensure the complete coverage of the mounting hole 201. At the same time, the area of ​​the adhesive tape 4 is smaller than the area of ​​the inner surface of the bottom plate 2, ensuring that the adhesive tape 4 is bonded to the inner surface of the bottom plate 2 in a single layer, and will not cause multi-layer folding due to the excessive size of the adhesive tape 4, thereby ensuring the energy density of the battery.

[0053] Please refer to the attached Figure 3 In some embodiments of the present application, the battery cell includes a plurality of bare battery cells; the explosion-proof valve 3 has a first region. In a cross section perpendicular to the first direction, the projected area of ​​all bare battery cells is S4, and the projected area of ​​the first region is S5, and S4 and S5 satisfy: 3≤S4 / S5≤10, for example, S4 / S5 can be any one of 3, 4, 5, 6, 7, 8, 9, and 10.

[0054] It should be noted that the first area is at least a part of the explosion-proof valve 3; in some embodiments, the first area may be the valve opening area of ​​the explosion-proof valve 3; the valve opening area refers to the area of ​​the explosion opening of the explosion-proof valve 3 after the explosion of the explosion-proof valve 3, that is, the actual pressure relief area of ​​the explosion-proof valve 3; the projection area of ​​the valve opening area in the cross section perpendicular to the first direction, that is, the area of ​​the valve opening area, is also the area of ​​the actual pressure relief area.

[0055] It should be further explained that only one bare cell can be provided, in which case the projection area of ​​the bare cell in the cross section perpendicular to the first direction is the top surface area or the bottom surface area of ​​the bare cell. Of course, multiple bare cells can also be provided, and the multiple bare cells are arranged in sequence, and the arrangement direction of the bare cells is perpendicular to the first direction. In this case, the projection area of ​​all bare cells in the cross section perpendicular to the first direction is the sum of the top surface area or the sum of the bottom surface area of ​​all bare cells.

[0056] The ratio of the bottom surface area S4 of all bare cells to the area S5 of the valve opening area is limited to the range of 3-10. Under the premise of ensuring the supporting performance of the shell, the area of ​​the actual pressure relief area of ​​the explosion-proof valve 3 can be matched with the size of the cell and the required flow rate of the exhaust gas. When the internal pressure of the battery exceeds the safety threshold, the shell is guaranteed to have sufficient pressure relief area to quickly release excessive pressure in a short time to prevent the battery from exploding.

[0057] Please refer to the attached Figure 3 In some embodiments of the present application, the outer surface of the bare cell is covered with a Mylar film 5. A bottom support plate 6 is provided on the inner surface of the bottom plate 2. The bottom support plate 6 is provided with a first through hole 7, and a second through hole is provided on the side opposite to the Mylar film 5 and the bottom support plate 6, and the first through hole 7 is connected to the second through hole.

[0058] Further, a plurality of first through holes 7 are provided; a plurality of second through holes are provided; the plurality of first through holes are connected to the plurality of second through holes. Preferably, the plurality of first through holes 7 are connected to the plurality of second through holes one-to-one.

[0059] In addition to arranging the multiple first through holes 7 and the multiple second through holes in a one-to-one connection setting, other forms of settings can also be used, that is, the multiple first through holes 7 and the multiple second through holes are staggered to ensure that each first through hole 7 has a second through hole connected to it, so as to ensure normal pressure relief and exhaust effects.

[0060] It should be noted that the bottom support plate 6 and the Mylar film 5 are connected together by hot melt; the first through hole 7 and the second through hole which are positioned opposite to each other are spliced ​​into a through communication channel, so the bottom support plate 6 and the Mylar film 5 form a total of multiple communication channels, and the multiple communication channels are arranged at intervals.

[0061] A plurality of through-going communication channels are provided on the Mylar film 5 and the bottom support plate 6 to facilitate the electrolyte to flow in the shell and better infiltrate the battery core; when the battery is abnormal, the explosion-proof valve 3 can better explode and release pressure.

[0062] Please refer to the attached Figure 3 In some embodiments of the present application, the extension length of the first through hole 7 and the extension length of the second through hole are both parallel to the first direction. In a cross section perpendicular to the first direction, the mounting hole 201 has a first projection, the area of ​​the first projection is S2, and the sum of the projection areas of the first through hole 7 located in the first projection is S6; S2 and S6 satisfy: 1.5≤S2 / S6≤5, for example, S2 / S6 can be any one of 1.5, 2, 2.5, 3, 3.5, 4, 4.5, and 5.

[0063] The ratio of the area S2 of the mounting hole 201 to the area of ​​all the first through holes 7 under the corresponding area of ​​the mounting hole 201 and S6 is limited to a range of 1.5-5, so as to ensure that the bottom support plate 6 has sufficient supporting strength and at the same time ensure the discharge speed of the electrolyte and the gas, so that when the battery is abnormal, the explosion-proof valve 3 can be better exploded and depressurized.

[0064] Please refer to the attached Figure 5 In some embodiments of the present application, the mounting hole 201 is a stepped hole having a plurality of hole sections, wherein the first hole section close to the outer surface of the bottom plate 2 has the largest hole diameter, and a stepped surface is formed at the junction of the first hole section and the adjacent hole section. The explosion-proof valve 3 is fixedly arranged on the stepped surface, and the explosion-proof valve 3 does not protrude from the outer surface of the bottom plate 2.

[0065] It should be noted that the step hole may have two hole sections or more than two hole sections. The explosion-proof valve 3 is welded to the step surface.

[0066] The step surface of the step hole provides a welding area for the explosion-proof valve 3, and the first hole section provides a storage space for the explosion-proof valve 3, so as to prevent the explosion-proof valve 3 from increasing the volume of the battery too much; the explosion-proof valve 3 does not protrude from the outer surface of the bottom plate 2, thereby ensuring the energy density of the battery and avoiding collision damage to the explosion-proof valve 3 caused by external factors.

[0067] Please refer to the attached Figure 5 In some embodiments of the present application, the explosion-proof valve 3 includes a middle area 301 and an edge area 302 arranged around the middle area 301, and the edge area 302 is at least partially fixedly arranged on the step surface. Along the first direction, the thickness of the edge area 302 is h, the depth of the first hole section is a, and h and a satisfy: 0.05mm≤ah≤2mm.

[0068] Please refer to the attached Figure 5 It should be further explained that, along the first direction, the thickness of the middle area 301 is smaller than the thickness of the edge area 302. The opening area of ​​the explosion-proof valve 3 is located in the middle area 301. The thickness of the edge area 302 is relatively large, which can ensure the welding effect of the explosion-proof valve 3 on the step surface of the mounting hole 201 and avoid the risk of accidental detachment of the battery during normal use; the size of the middle area 301 is thinned, and when the battery is abnormal, the normal explosion of the explosion-proof valve 3 can be ensured to avoid battery explosion.

[0069] As described above, it is ensured that the hole depth of the first hole section is greater than the thickness of the edge region 302, and it can be well ensured that the edge region 302 welded to the step surface of the mounting hole 201 does not protrude from the outer surface of the bottom plate 2. When the difference between the hole depth a of the first hole section and the thickness h of the edge region 302 is less than 0.05 mm, the welding process of the edge region 302 on the step surface is required to be relatively high; when the difference between the hole depth a of the first hole section and the thickness h of the edge region 302 is greater than 2 mm, the supporting strength of the bottom plate 2 will be excessively attenuated.

[0070] Please refer to the attached Figure 4 In certain embodiments of the present application, the bare cell includes a pole piece, which includes a current collector and a pole ear 8 connected to the current collector; along a first direction, the pole ear 8 includes a first part 801 and a second part 802, the first part 801 is close to the current collector, and the second part 802 is connected to the electrode adapter sheet 9.

[0071] It should be noted that the first portion 801 of the pole tab 8 is welded to the current collector; the second portion 802 is welded to the electrode adapter 9. The electrode adapter 9 is welded to the pole 10 provided on the top cover 1. The pole piece can be a positive pole piece or a negative pole piece; accordingly, the pole tab 8 can be a positive pole tab or a negative pole tab; the pole tab 8 can be a pole tab welded in the pole tab groove of the current collector, or a pole tab roll-welded with the current collector, which will not be listed one by one here.

[0072] The pole tab 8 is divided into a first portion 801 and a second portion 802 , which ensures the welding effect between the first portion 801 and the current collector, and at the same time ensures the welding effect between the second portion 802 and the electrode adapter 9 , thereby ensuring the current carrying capacity of the pole tab 8 .

[0073] Please refer to the attached Figure 4 In some embodiments, the first portion 801 includes a tab shoulder 803 that is not connected to the second portion 802. A through injection hole 101 is provided on the top cover 1. In a cross section perpendicular to the first direction, the projection of the injection hole 101 is located within the projection of the tab shoulder 803.

[0074] It should be noted that the width of the first portion 801 is greater than the width of the second portion 802, and in a cross section perpendicular to the first direction, the projection of the first portion 801 includes an area that does not overlap with the projection of the second portion 802, and the area is the pole ear shoulder 803. Further, a step structure is formed at the junction of the first portion 801 and the second portion 802, and the step surface of the step structure is located at the pole ear shoulder 803.

[0075] As mentioned above, the width of the first portion 801 is greater than the width of the second portion 802, thereby ensuring the welding effect between the first portion 801 and the current collector, and the width of the second portion 802 is reduced, which is convenient for welding with the adapter.

[0076] The present application realizes the staggered setting of the injection hole 101 and the second part 802; when the electrolyte is injected into the shell through the injection hole 101, the electrolyte can avoid the weld mark between the second part 802 and the electrode adapter 9, avoiding the impact on the above-mentioned weld mark, thereby ensuring the electrical connection effect between the second part 802 and the electrode adapter 9.

[0077] In summary, the present application also provides an electrical device, which includes the battery described above.

[0078] Since the electrical device has the battery as described above, the beneficial effects of the battery on the electrical device can be found above and will not be described in detail here.

[0079] The components and devices involved in this application are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the drawings. As will be appreciated by those skilled in the art, these components and devices can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open words, meaning "including but not limited to", and can be used interchangeably with them. The words "or" and "and" used here refer to the words "and / or" and can be used interchangeably with them, unless the context clearly indicates otherwise. The word "such as" used here refers to the phrase "such as but not limited to", and can be used interchangeably with it.

[0080] It should also be noted that in the device of the present application, each component can be decomposed and / or reassembled, and these decompositions and / or reassemblies should be regarded as equivalent solutions of the present application.

[0081] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present application. Therefore, the present application is not intended to be limited to the aspects shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0082] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

[0083] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A battery, characterized in that: It comprises a shell, a top cover (1), and a battery cell arranged in a closed space enclosed by the shell and the top cover (1); the shell comprises a bottom plate (2) opposite to the top cover (1); The bottom plate (2) is provided with a through installation hole (201), and an explosion-proof valve (3) is arranged in the installation hole (201); and adhesive tape (4) is arranged on the inner surface of the bottom plate (2); In a cross section perpendicular to a first direction, the projection of the adhesive tape (4) completely covers the projection of the mounting hole (201); the first direction is parallel to a direction from the top cover (1) to the bottom plate (2).

2. The battery according to claim 1, characterized in that In a cross section perpendicular to the first direction, the projection area of ​​the adhesive tape (4) is S1, the projection area of ​​the mounting hole (201) is S2, and the projection area of ​​the inner surface of the bottom plate (2) is S3, and S1, S2, and S3 satisfy: 1.2≤S1 / S2≤5; S1<S3.

3. The battery according to claim 1, characterized in that The battery cell includes a plurality of bare battery cells; The explosion-proof valve (3) has a first area; in a cross section perpendicular to the first direction, the projected area of ​​all the bare cells is S4, the projected area of ​​the first area is S5, and S4 and S5 satisfy: 3≤S4 / S5≤10.

4. The battery according to claim 3, characterized in that The outer surface of the bare battery core is covered with a Mylar film (5); The inner surface of the bottom plate (2) is provided with a bottom support plate (6); The bottom support plate (6) is provided with a first through hole (7), and the side surface of the Mylar film (5) opposite to the bottom support plate (6) is provided with a second through hole, and the first through hole (7) is connected to the second through hole.

5. The battery according to claim 4, characterized in that The extension length of the first through hole (7) and the extension length of the second through hole are parallel to the first direction; In a cross section perpendicular to the first direction, the mounting hole (201) has a first projection, the area of ​​the first projection is S2, and the sum of the projection areas of the plurality of first through holes (7) located in the first projection is S6; S2 and S6 satisfy: 1.5≤S2 / S6≤5.

6. The battery according to claim 1, characterized in that The mounting hole (201) is a stepped hole having a plurality of hole sections, wherein the first hole section close to the outer surface of the bottom plate (2) has the largest hole diameter, and a stepped surface is formed at the junction between the first hole section and its adjacent hole section; The explosion-proof valve (3) is fixedly arranged on the step surface, and the explosion-proof valve (3) does not protrude from the outer surface of the bottom plate (2).

7. The battery according to claim 6, characterized in that The explosion-proof valve (3) comprises a middle area (301) and an edge area (302) arranged around the middle area (301), and the edge area (302) is at least partially fixedly arranged on the step surface; Along the first direction, the thickness of the edge region (302) is h, the depth of the first hole segment is a, and h and a satisfy: 0.05mm≤ah≤2mm.

8. The battery according to claim 1, characterized in that The battery cell comprises a plurality of bare battery cells, each of which comprises a pole piece, and each pole piece comprises a current collector and a pole ear (8) connected to the current collector; Along the first direction, the electrode tab (8) includes a first portion (801) and a second portion (802), wherein the first portion (801) is close to the current collector.

9. The battery according to claim 8, characterized in that The first portion (801) includes a tab shoulder (803) that is not connected to the second portion (802); The top cover (1) is provided with a through injection hole (101); in a cross section perpendicular to the first direction, the projection of the injection hole (101) is located within the projection of the tab shoulder (803).

10. An electrical device, characterized in that: A battery comprising the battery according to any one of claims 1 to 9.

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