Battery cell, battery, battery module, battery pack, and electrical device

Abstract

An electrical device, the electrical device comprising a battery pack, the battery pack comprising a battery or a battery module, the battery module comprising the battery, the battery comprising a battery cell, and the battery cell comprising a casing, an electrode core, and a separation member. The electrode core is arranged within the casing; two ends of the electrode core in the length direction are a first end and a second end, where the first end is provided with a positive electrode tab and a negative electrode tab. The separation member is arranged within the casing, the separation member is located between the casing and the second end of the electrode core, and the separation member separates the electrode core from the casing.

Description

Battery cells, batteries, battery modules, battery packs and electrical devices

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on December 29, 2023, with application number 202323658353.4 and titled “Battery Cells, Batteries, Battery Modules, Battery Packs and Electrical Devices,” the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present application relates to the field of vehicle technology, and in particular to a battery cell, a battery, a battery module, a battery pack and an electrical device. Background Art

[0004] As the core component of power batteries, battery cells play a significant role in them. They determine the quality of power batteries and, of course, the battery life and capacity of vehicles.

[0005] In the related art, the battery cell contains a positive electrode tab and a negative electrode tab. When the positive electrode tab and the negative electrode tab are located at the same end in the length direction of the battery cell, that is, when the tabs are led out at the same end, the current carried by the battery cell does not need to pass through the shell, which can reduce the impedance of the battery. However, the end of the electrode core away from the positive electrode tab and the negative electrode tab is easily damaged, which shortens the service life of the electrode core.

[0006] Public content

[0007] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, one purpose of the present application is to provide a battery cell that separates the core from the housing by a separator, thereby protecting the core and extending the service life of the core.

[0008] The second objective of this application is to provide a battery using the above-mentioned battery cell.

[0009] The third object of this application is to provide a battery module using the above-mentioned battery.

[0010] The fourth object of the present application is to provide a battery pack using the above-mentioned battery or the above-mentioned battery module.

[0011] The fifth objective of this application is to provide an electrical device using the above-mentioned battery pack.

[0012] According to the battery cell of the first aspect embodiment of the present application, it includes: a shell; a pole core, which is arranged in the shell, and the two ends of the pole core in the length direction are respectively a first end and a second end, and the first end is provided with a positive pole tab and a negative pole tab; and a separator, which is arranged in the shell, and the separator is located between the second end of the pole core and the shell, and the separator separates the pole core from the shell.

[0013] According to the battery cell of the present application, a separator is provided to separate the second end of the pole core from the housing (e.g., the bottom wall of the housing). The separator has a protective effect on the pole core, preventing the pole core from direct contact with the housing and damage to the pole core, thereby extending the service life of the pole core and the battery cell. In addition, the separator is easy to install and operate, thereby improving the assembly efficiency of the battery cell. In addition, the positive and negative pole tabs are provided at the first end of the battery cell, so that the current on the pole core cannot pass through the housing, reducing the structural impedance of the battery cell.

[0014] According to some embodiments of the present application, at least one through hole is formed on the separator.

[0015] According to some embodiments of the present application, a pressure relief device is provided on the housing, and the pressure relief device is configured to release the internal pressure of the battery cell.

[0016] According to some embodiments of the present application, the housing includes a shell and a bottom cover plate connected to each other, the separator separates the pole core from the bottom cover plate, and the pressure relief device is provided on the bottom cover plate.

[0017] According to some embodiments of the present application, at least a portion of the pressure relief device is opposite to the through hole along the thickness direction of the partition.

[0018] According to some embodiments of the present application, the area where the projection of at least a portion of the pressure relief device on the separator along the thickness direction of the separator overlaps with the through hole is S1, and the cross-sectional area of ​​the pressure relief device along a plane perpendicular to the thickness direction of the separator is S2, wherein S1 and S2 satisfy: 50%≤S1 / S2≤100%.

[0019] According to some embodiments of the present application, the cross-sectional area of ​​the through hole along a plane perpendicular to the thickness direction of the separator is S3, and the cross-sectional area of ​​the separator along a plane perpendicular to the thickness direction of the separator is S4, wherein S3 and S4 satisfy: 30%≤S3 / S4≤80%.

[0020] According to some embodiments of the present application, there are multiple through holes, and the multiple through holes constitute at least one first through hole group and at least one second through hole group, the first through hole group includes multiple first through holes, and the multiple first through holes are arranged at radial intervals along the partition, the second through hole group includes multiple second through holes, and the multiple second through holes are arranged at circumferential intervals along the partition, and the multiple second through holes and the multiple first through holes are spaced apart from each other.

[0021] According to some embodiments of the present application, a cross-sectional area of ​​the second through hole along a plane perpendicular to the thickness direction of the separator is greater than a cross-sectional area of ​​the first through hole along a plane perpendicular to the thickness direction of the separator.

[0022] According to some embodiments of the present application, the cross-sectional areas of the plurality of first through holes along a plane perpendicular to the thickness direction of the partition are the same; or, the cross-sectional areas of at least two of the plurality of first through holes along a plane perpendicular to the thickness direction of the partition are different.

[0023] According to some embodiments of the present application, there are multiple first through hole groups, and the multiple first through hole groups are arranged at intervals along the circumference of the partition, and the second through hole is located between two adjacent groups of the first through hole groups.

[0024] According to some embodiments of the present application, the minimum distance between any second through-hole and the first through-hole of the adjacent first through-hole group adjacent to the edge of the separator is l1, where l1 satisfies the following conditions: 0.5 mm ≤ l1 ≤ 3 mm; and / or the minimum distance between two adjacent first through-holes of the first through-hole group adjacent to the edge of the separator is l2, where l2 satisfies the following conditions: 0.5 mm ≤ l2 ≤ 3 mm.

[0025] According to some embodiments of the present application, the thickness of the separator is h, wherein h satisfies: 0.3 mm ≤ h ≤ 2 mm.

[0026] According to some embodiments of the present application, the separator is a polyethylene terephthalate piece or a polypropylene piece.

[0027] The battery according to the second embodiment of the present application includes the battery cell according to the first embodiment of the present application.

[0028] The battery module according to the third embodiment of the present application includes the battery according to the above-mentioned second embodiment of the present application.

[0029] The battery pack according to the fourth embodiment of the present application includes the battery according to the above-mentioned second embodiment of the present application or the battery module according to the above-mentioned third embodiment of the present application.

[0030] An electrical device according to an embodiment of the fifth aspect of the present application includes a battery pack according to an embodiment of the fourth aspect of the present application.

[0031] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0033] FIG1 is a schematic diagram of a battery cell according to an embodiment of the present application;

[0034] FIG2 is an exploded view of a battery cell according to an embodiment of the present application;

[0035] FIG3 is a schematic diagram of a separator of a battery cell according to an embodiment of the present application;

[0036] FIG4 is a schematic diagram of a battery cell according to an embodiment of the present application from another angle;

[0037] FIG5 is an exploded view of a battery cell according to an embodiment of the present application from another angle;

[0038] FIG6 is a schematic diagram of the assembly of a separator and a pressure relief device of a battery cell according to an embodiment of the present application;

[0039] FIG7 is a schematic diagram of the assembly of a separator and a pressure relief device of a battery cell according to another embodiment of the present application;

[0040] FIG8 is a schematic diagram of the assembly of a separator and a pressure relief device of a battery cell according to yet another embodiment of the present application;

[0041] FIG9 is a schematic block diagram of a battery according to an embodiment of the present application;

[0042] FIG10 is a schematic block diagram of a battery module according to an embodiment of the present application;

[0043] FIG11 is a schematic block diagram of a battery pack according to an embodiment of the present application;

[0044] FIG12 is another schematic block diagram of a battery pack according to an embodiment of the present application;

[0045] FIG13 is a schematic block diagram of an electric device according to an embodiment of the present application.

[0046] Reference numerals:

[0047] Power device 4000, battery pack 3000, battery module 2000, battery 1000,

[0048] Battery Cell 100,

[0049] Shell 1, pressure relief device 11, shell 120, bottom cover 12, reinforcement rib 121, protective member 13,

[0050] Pole core 2, first end 21, positive pole tab 211, negative pole tab 212, second end 22,

[0051] Separator 3 , through hole 31 , first through hole group 32 , first through hole 321 , second through hole group 33 , second through hole 331 . DETAILED DESCRIPTION

[0052] The embodiments of the present application are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. The battery cell 100 according to the first embodiment of the present application is described below with reference to Figures 1 to 8 .

[0053] As shown in FIG1 and FIG2 , the battery cell 100 according to the embodiment of the first aspect of the present application includes a housing 1 , a pole core 2 and a separator 3 .

[0054] Specifically, the pole core 2 and the separator 3 are both disposed within the housing 1. The two ends of the pole core 2 in the longitudinal direction (e.g., the up and down directions indicated by the arrows in FIG1 ) are respectively a first end 21 and a second end 22. The first end 21 is provided with a positive electrode tab 211 and a negative electrode tab 212. The separator 3 is located between the second end 22 of the pole core 2 and the housing 1, and the separator 3 separates the pole core 2 from the housing 1. For example, in the examples of FIG1 and FIG2 , the upper end of the pole core 2 is the first end 21, and the lower end of the pole core 2 is the second end 22, that is, the separator 3 is located between the lower surface of the second end 22 of the pole core 2 and the bottom wall of the housing 1, and the pole core 2 is separated from the inner wall of the housing 1 by the separator 3.

[0055] With such a configuration, the battery cell 100 adopts the same-end lead-out, and the current carrying capacity of the battery cell 100 does not need to pass through the outer shell 1, which can reduce the structural impedance. Moreover, the battery cell 100 can be provided with an exhaust structure at only one end (such as the second end 22 mentioned above), thereby helping to improve the space utilization of the battery cell 100. In addition, the second end 22 of the pole core 2 is separated from the outer shell 1 by the separator 3, and the second end 22 of the pole core 2 does not contact the bottom wall of the outer shell 1. The separator 3 has a protective effect on the pole core 2, which can prevent the pole core 2 from being directly in contact with the outer shell 1 and causing damage to the pole core 2, thereby extending the service life of the pole core 2 and thus extending the service life of the battery cell 100. In addition, the installation operation of the separator 3 is simple, and the separator 3 can be placed in the outer shell 1, thereby improving the assembly efficiency of the battery cell 100.

[0056] According to the battery cell 100 of the present application, the second end 22 of the pole core 2 is separated from the housing 1 (e.g., the bottom wall of the housing 1) by providing a separator 3. The separator 3 has a protective effect on the pole core 2, preventing the pole core 2 from directly contacting the housing 1 and damaging the pole core 2, thereby extending the service life of the pole core 2 and the battery cell 100. In addition, the installation operation of the separator 3 is simple, thereby improving the assembly efficiency of the battery cell 100. In addition, the positive electrode tab 211 and the negative electrode tab 212 are provided at the first end 21 of the battery cell 100, so that the current on the pole core 2 cannot pass through the housing 1, thereby reducing the structural impedance of the battery cell 100.

[0057] According to some embodiments of the present application, referring to FIG. 2 and FIG. 3 , at least one through-hole 31 is formed in the separator 3. For example, in the example of FIG. 3 , the through-hole 31 extends through the separator 3 along its thickness (e.g., in the vertical direction indicated by the arrows in FIG. 3 ). This arrangement allows the electrolyte to be stored in the through-hole 31, thereby increasing the electrolyte storage space, reducing the risk of electrolyte overflow, and preventing damage to the battery cell 100.

[0058] According to some embodiments of the present application, referring to Figures 4 and 5 , a pressure relief device 11 is provided on the housing 1. The pressure relief device 11 is configured to release the internal pressure of the battery cell 100. With this arrangement, when the pressure or temperature inside the battery cell 100 reaches a threshold, the gas inside the battery cell 100 can be released through the pressure relief device 11, releasing the internal pressure of the battery cell 100 and facilitating normal use of the battery cell 100.

[0059] According to some embodiments of the present application, referring to FIG5 , the housing 1 includes a housing 120 and a bottom cover plate 12 connected to each other, a separator 3 separates the pole core 2 from the bottom cover plate 12, and a pressure relief device 11 is provided on the bottom cover plate 12. For example, in the example of FIG5 , the bottom cover plate 12 is located at the lower end of the housing 120, the bottom cover plate 12 and the housing 120 are connected by welding, and the pressure relief device 11 is provided on the side wall of the bottom cover plate 12 away from the separator 3. Thus, by providing the housing 1 as a separate body, the processing accuracy of the housing 120 and the bottom cover plate 12 is improved, thereby improving the processing accuracy of the housing 1. Exemplarily, the pressure relief device 11 is provided on the bottom cover plate 12 of the housing 120. The pressure relief device 11 and the bottom cover plate 12 can be an integrally formed structure or a separately provided structure. For example, the pressure relief device 11 is an area with a weak structure formed on the bottom cover plate 12, such as the pressure relief device 11 is an area with a notched groove provided on the bottom cover plate 12. Of course, the pressure relief device 11 and the bottom cover plate 12 may also be separate structures, and the pressure relief device 11 may be connected to the bottom cover plate 12 by welding or other methods. Accordingly, the pressure relief device 11 may be, for example, an explosion-proof valve, an explosion-proof disk, an air valve, a pressure relief valve, or a safety valve. It should be noted that the pressure relief device 11 may also be provided on the housing 120 to achieve pressure relief within the battery cell 100.

[0060] According to some embodiments of the present application, referring to FIG5 and FIG6 , at least a portion of the pressure relief device 11 is opposite to the through hole 31 along the thickness direction of the separator 3. For example, in the examples of FIG5 and FIG6 , at least a portion of the pressure relief device 11 is in communication with the through hole 31. With this arrangement, the through hole 31 functions as an exhaust channel. When the pressure inside the battery cell 100 is too high, the gas inside the battery cell 100 can flow through the through hole 31 to the pressure relief device 11 and then be discharged to the outside of the battery cell 100, thereby facilitating the pressure relief of the battery cell 100 and the smooth opening of the pressure relief device 11, thereby improving the safety of the battery cell 100.

[0061] Optionally, the area where the projection of the at least a portion of the pressure relief device 11 on the separator 3 along the thickness direction of the separator 3 overlaps with the through hole 31 is S1 (i.e., the area of ​​the pressure relief device 11 opposite the through hole 31 along the thickness direction of the separator 3), and the cross-sectional area of ​​the pressure relief device 11 along a plane perpendicular to the thickness direction of the separator 3 (i.e., the cross-sectional area of ​​the pressure relief device 11 along the vertical direction) is S2, where S1 and S2 satisfy the following: 50% ≤ S1 / S2 ≤ 100%. For example, when the ratio S1 / S2 of the area S1 where the at least a portion of the pressure relief device 11 opposite the through hole 31 along the thickness direction of the separator 3 to the cross-sectional area S2 of the pressure relief device 11 is less than 50%, the cross-sectional area of ​​the exhaust passage of the pressure relief device 11 is small. Therefore, after the pressure relief device 11 is opened, the amount of gas flowing through the exhaust passage of the pressure relief device 11 per unit time is small, thereby reducing the exhaust speed of the battery cell 100 and hindering the pressure relief of the battery cell 100. Therefore, by setting the area S1 where at least a portion of the pressure relief device 11 is opposite to the through hole 31 along the thickness direction of the separator 3 and the cross-sectional area S2 of the pressure relief device 11 to satisfy 50%≤S1 / S2≤100%, the pressure relief capacity of the pressure relief device 11 is effectively guaranteed, and the pressure relief area of ​​the battery cell 100 is guaranteed. Therefore, after the pressure relief device 11 is opened, the amount of gas flowing through the exhaust channel of the pressure relief device 11 per unit time is relatively large, thereby increasing the exhaust speed of the battery cell 100 and improving the safety of the battery cell 100.

[0062] According to some embodiments of the present application, the cross-sectional area of ​​the through-hole 31 along a plane perpendicular to the thickness of the separator 3 is S3, and the cross-sectional area of ​​the separator 3 along a plane perpendicular to the thickness of the separator 3 is S4, where S3 and S4 satisfy the following: 30% ≤ S3 / S4 ≤ 80%. For example, when the ratio S3 / S4 of the cross-sectional area S3 of the through-hole 31 along a plane perpendicular to the thickness of the separator 3 to the cross-sectional area S4 of the separator 3 along a plane perpendicular to the thickness of the separator 3 is less than 30%, the cross-sectional area of ​​the through-hole 31 is small, resulting in a small storage space for the electrolyte, which in turn makes it easy for the electrolyte to overflow during injection and damage the battery cell 100. In addition, the small size of the through-hole 31 makes it difficult to inject the electrolyte into the battery cell 100. When the ratio (S3 / S4) of the cross-sectional area S3 of through-hole 31 along a plane perpendicular to the thickness of separator 3 to the cross-sectional area S4 of separator 3 along a plane perpendicular to the thickness of separator 3 is greater than 80%, through-hole 31 occupies a large space in separator 3, reducing the structural strength of separator 3 and hindering the long-term use of separator 3. Therefore, by ensuring that the cross-sectional area S3 of through-hole 31 along a plane perpendicular to the thickness of separator 3 and the cross-sectional area S4 of separator 3 along a plane perpendicular to the thickness of separator 3 satisfy the relationship of 30% ≤ S3 / S4 ≤ 80%, electrolyte storage space is increased, the risk of electrolyte overflow is reduced, and thus damage to battery cell 100 is avoided. Furthermore, the structural strength of separator 3 is maintained, thereby enhancing the protective effect of separator 3 on electrode core 2 and thereby extending the service life of battery cell 100.

[0063] According to some embodiments of the present application, referring to FIG3 and FIG6-8, there are multiple through holes 31. In the description of the present application, "multiple" means two or more than two. The multiple through holes 31 constitute at least one first through hole group 32 and at least one second through hole group 33. The first through hole group 32 includes a plurality of first through holes 321, and the plurality of first through holes 321 are spaced apart along the radial direction of the separator 3. The second through hole group 33 includes a plurality of second through holes 331, and the plurality of second through holes 331 are spaced apart along the circumferential direction of the separator 3. The plurality of second through holes 331 and the plurality of first through holes 321 are spaced apart from each other.

[0064] For example, in the examples of Figures 3 and 6-8 , the second through-hole group 33 includes four second through-holes 331, which are spaced apart along the circumference of the separator 3. The first through-hole group 32 and the second through-hole group 33 are spaced apart from each other, with multiple first through-holes 321 disposed between adjacent second through-holes 331. This arrangement provides a suitable number and arrangement of through-holes 31, further increasing electrolyte storage space and thereby preventing electrolyte overflow and, consequently, damage to the battery cell 100. Furthermore, the material usage of the separator 3 is reduced, thereby lowering the production cost of the separator 3 and reducing the weight of the separator 3, thereby reducing the weight of the battery cell 100. Furthermore, at least one of the multiple through-holes 31 is positioned opposite the pressure relief device 11, ensuring communication between the through-hole 31 and the pressure relief device 11, improving smooth gas discharge, and facilitating assembly of the separator 3 (that is, even after the separator 3 is rotated along its central axis, the through-hole 31 can still be positioned opposite the pressure relief device 11). Furthermore, the rational layout of the first and second through-hole groups 33 and 33 ensures the normal operation of the separator 3 while also improving the structural strength of the separator 3, thereby enhancing the long-term stability of the separator 3 and improving its aesthetics. It should be noted that the number and arrangement of the first through-holes 321, as well as the number and arrangement of the second through-holes 331, can be specifically configured based on actual use to better meet practical requirements. For example, referring to Figures 7 and 8, schematic diagrams of the separator 3 relative to the pressure relief device 11 in different states after rotation are shown.

[0065] According to some embodiments of the present application, referring to FIG6 , the cross-sectional area of ​​the second through-hole 331, as measured along a plane perpendicular to the thickness of the separator 3, is greater than the cross-sectional area of ​​the first through-hole 321, as measured along a plane perpendicular to the thickness of the separator 3. For example, in the example of FIG6 , the first through-hole 321 can be circular, and the second through-hole 331 can be polygonal, with the second through-hole 331 extending in a curved manner along the circumference of the separator 3. This arrangement allows the separator 3 to be positioned at any angle along its circumference when assembled with the housing 1. Specifically, when the separator 3 is rotated relative to the housing 1, the second through-hole 331 can be aligned with the pressure relief device 11, thereby facilitating pressure relief for the battery cell 100 and effectively ensuring the proper operation of the pressure relief device 11, further enhancing the safety of the battery cell 100. Furthermore, the aesthetics of the separator 3 are enhanced. Furthermore, the simple structure of the first and second through-holes 321 and 331 facilitates production and processing, facilitating mass production of the separator 3. It should be noted that the shapes of the first through hole 321 and the second through hole 331 can be specifically set according to actual usage conditions to better meet practical applications.

[0066] According to some embodiments of the present application, referring to FIG6 , the cross-sectional areas of the plurality of first through holes 321 along a plane perpendicular to the thickness direction of the separator 3 are all the same. This improves the balance of the separator 3, thereby increasing the stability of the separator 3 after installation, and also simplifies the structure of the separator 3, facilitating mass production of the separator 3.

[0067] According to other embodiments of the present application, referring to FIG6 , at least two of the plurality of first through holes 321 have different cross-sectional areas along a plane perpendicular to the thickness direction of the separator 3. Thus, while ensuring the structural strength of the separator 3, multiple first through holes 321 with different cross-sectional areas can be provided to increase the cross-sectional areas of the multiple through holes 31, thereby facilitating the first through holes 321 to be opposite the pressure relief device 11, while also effectively increasing the electrolyte storage space. Furthermore, it is convenient to rationally arrange the first through holes 321 based on the arrangement of the second through holes 331, making the arrangement of the multiple first through holes 321 and the multiple second through holes 331 more compact, thereby optimizing the spatial design of the separator 3.

[0068] According to some embodiments of the present application, referring to FIG3 and FIG6 , there are multiple first through-hole groups 32 , and the multiple first through-hole groups 32 are arranged at intervals along the circumference of the separator 3 , and the second through-holes 331 are located between two adjacent first through-hole groups 32 . For example, in the examples of FIG3 and FIG6 , there are four first through-hole groups 32 , and the four first through-hole groups 32 and the four second through-holes 331 are arranged at intervals along the circumference of the separator 3 , and the first through-hole groups 32 and the second through-holes 331 are symmetrical along the center of the separator 3 . With such an arrangement, the weight of the separator 3 is further reduced and the electrolyte storage space is further increased through the combined action of the multiple first through-hole groups 32 . In addition, the aesthetics of the separator 3 is improved, and the stability of the separator 3 is improved, so that the separator 3 can better protect the electrode core 2 , and it is also conducive to the mass production of the separator 3 .

[0069] According to some embodiments of the present application, referring to FIG6 , the minimum distance between any second through hole 331 and a first through hole 321 of an adjacent first through hole group 32 adjacent to an edge of a separator 3 is l1, where l1 satisfies the following conditions: 0.5 mm ≤ l1 ≤ 3 mm. For example, when the minimum distance l1 between any second through hole 331 and a first through hole 321 of an adjacent first through hole group 32 adjacent to an edge of a separator 3 is less than 0.5 mm, the distance between the second through hole 331 and the first through hole 321 of an adjacent first through hole group 32 adjacent to an edge of a separator 3 is relatively close, thereby reducing the structural strength of the separator 3, making the separator 3 more susceptible to breakage, and thereby shortening the service life of the separator 3. When the minimum distance l1 between any second through hole 331 and the first through hole 321 of the adjacent first through hole group 32 adjacent to the edge of the separator 3 is greater than 3 mm, after the separator 3 is installed, the connection between any second through hole 331 and the first through hole 321 of the adjacent first through hole group 32 adjacent to the edge of the separator 3 is likely to block the pressure relief device 11, thereby affecting the exhaust of the pressure relief device 11 and, in turn, hindering the normal use of the battery cell 100. Therefore, by setting the minimum distance l1 between any second through hole 331 and the first through hole 321 of the adjacent first through hole group 32 adjacent to the edge of the separator 3 to meet 0.5 mm ≤ l1 ≤ 3 mm, the layout of the first through holes 321 and the second through holes 331 is rationalized, the structural strength of the separator 3 is improved, thereby enhancing the protective effect of the separator 3 on the battery cell 100 and extending the service life of the separator 3. In addition, the through hole 31 is advantageously opposite the pressure relief device 11, thereby increasing the exhaust channel of the pressure relief device 11 and allowing gas to be smoothly discharged out of the battery cell 100.

[0070] According to other embodiments of the present application, referring to FIG6 , the minimum distance l2 between two adjacent first through holes 321 of the first through hole group 32 adjacent to the edge of the separator 3 is l2, where l2 satisfies the following: 0.5 mm ≤ l2 ≤ 3 mm. For example, when the minimum distance l2 between two adjacent first through holes 321 of the first through hole group 32 adjacent to the edge of the separator 3 is less than 0.5 mm, the connection portion between the two adjacent first through holes 321 of the first through hole group 32 adjacent to the edge of the separator 3 is narrow, thereby reducing the structural strength of the separator 3, making the separator 3 susceptible to breakage and damage, and thus shortening the service life of the separator 3. When the minimum distance l2 between two adjacent first through holes 321 of the first through hole group 32 adjacent to the edge of the separator 3 is greater than 3 mm, after the separator 3 is installed, the connection portion between the two adjacent first through holes 321 of the first through hole group 32 adjacent to the edge of the separator 3 blocks a large area of ​​the pressure relief device 11, thereby easily affecting the exhaust of the pressure relief device 11 and being detrimental to the safe use of the battery cell 100. Thus, by ensuring that the minimum distance l2 between two adjacent first through holes 321 of the first through hole group 32, which are located adjacent to the edge of the separator 3, satisfies 0.5 mm ≤ l2 ≤ 3 mm, the distance between two adjacent first through holes 321 is moderate, thereby improving the structural strength of the separator 3 and facilitating the normal use of the separator 3. Furthermore, the through holes 31 are advantageously positioned opposite the pressure relief device 11, thereby increasing the exhaust passage of the pressure relief device 11 and allowing gas to be smoothly discharged outside the battery cell 100.

[0071] According to some further embodiments of the present application, the minimum distance between any second through hole 331 and the first through hole 321 of the adjacent first through hole group 32 adjacent to the edge of the separator 3 is l1, wherein l1 satisfies: 0.5mm≤l1≤3mm. At the same time, the minimum distance between two adjacent first through holes 321 of the adjacent edge of the separator 3 of the first through hole group 32 is l2, wherein l2 satisfies: 0.5mm≤l2≤3mm. As a result, the structural strength of the separator 3 is improved, thereby improving the protective effect of the separator 3 on the pole core 2 and extending the service life of the separator 3. In addition, the pressure relief device 11 is easily connected to the through hole 31, so that when the internal air pressure of the battery cell 100 is too high, the gas can be smoothly discharged through the through hole 31 and the pressure relief device 11, thereby improving the safety of the battery cell 100.

[0072] Further, referring to Figure 3, the thickness of the separator 3 is h, where h satisfies: 0.3mm≤h≤2mm. For example, when the thickness h of the separator 3 is less than 0.3mm, the spatial volume of the through hole 31 is small, so that the amount of electrolyte stored in the through hole 31 is small, which makes the electrolyte easy to overflow, causing the battery cell 100 to be easily damaged. When the thickness h of the separator 3 is greater than 2mm, the space occupied by the separator 3 in the outer shell 1 is large, which reduces the space utilization rate inside the outer shell 1. Therefore, by setting the thickness h of the separator 3 to satisfy 0.3mm≤h≤2mm, the storage space for the electrolyte is increased, thereby preventing the electrolyte from overflowing during injection, and rationalizing the space occupied by the separator 3 in the outer shell 1, thereby improving the space utilization rate inside the outer shell 1.

[0073] According to some optional embodiments of the present application, the separator 3 is a polyethylene terephthalate piece or a polypropylene piece. When the separator 3 is set to a polyethylene terephthalate piece, the polyethylene terephthalate piece has electrical insulation, thereby hindering the current on the pole core 2 from flowing to the housing 1, thereby reducing the structural impedance. When the separator 3 is set to a polypropylene piece, polypropylene also has electrical insulation, thereby reducing the structural impedance, and the material source is wide. In addition, polypropylene has high-strength mechanical properties and good high-wear-resistant processing performance, thereby improving the protective effect of the separator 3 on the pole core 2 and extending the service life of the separator 3. Optionally, the separator 3 is injection molded. Thereby, the molding quality of the separator 3 is improved, and the production efficiency and processing accuracy of the separator 3 are also improved.

[0074] Further optionally, referring to Figure 5, the pressure relief device 11 is welded to the housing 1, and a protective member 13 is provided on the side of the pressure relief device 11 away from the housing 1. For example, in the example of Figure 5, the protective member 13 is opposite to the pressure relief device 11, and the protective member 13 is assembled with the housing 1. This arrangement increases the connection strength between the pressure relief device 11 and the housing 1, and prevents the pressure relief device 11 from falling off from the housing 1. In addition, the protective member 13 can protect the pressure relief device 11, thereby extending the service life of the pressure relief device 11. For example, the protective member 13 is injection molded by polyester resin. As a result, the production and processing of the protective member 13 is facilitated, the processing efficiency of the protective member 13 is improved, and the structural strength of the protective member 13 is also improved, which is beneficial to the long-term use of the protective member 13.

[0075] According to some optional embodiments of the present application, the pressure relief device 11 is formed by stamping or laser scoring steel, and has an initiation pressure of P, where P satisfies the following conditions: 0.5 MPa ≤ P ≤ 2 MPa. This allows for high production efficiency and precision in the pressure relief device 11, thereby improving the assembly precision of the pressure relief device 11 and the housing 1 and facilitating the long-term use of the pressure relief device 11.

[0076] Optionally, the housing 120 is formed cylindrically by stamping steel or by winding and welding sheet material, and the bottom cover plate 12 is re-formed by stamping steel, where the steel is corrosion-resistant. This strengthens the connection between the bottom cover plate 12 and the circumferential sidewalls of the housing 120, thereby increasing the structural strength of the housing 1 and facilitating long-term, stable use of the housing 1. Furthermore, the steel stamping process improves the flatness of the bottom cover plate 12.

[0077] Further, referring to Figure 5 , a reinforcing rib 121 is formed on the lower surface of the bottom cover 12. For example, in the example shown in Figure 4 , the reinforcing rib 121 is recessed from the lower surface of the bottom cover 12 toward the upper surface of the bottom cover 12. The reinforcing rib 121 is radially opposite the installation location of the pressure relief device 11 on the bottom cover 12. Thus, the provision of the reinforcing rib 121 improves the structural strength of the bottom cover 12, thereby improving the structural strength of the housing 1.

[0078] The battery 1000 according to the second embodiment of the present application includes the battery cell 100 according to the first embodiment of the present application, as shown in FIG9 .

[0079] According to the battery 1000 of the present application, by adopting the above-mentioned battery cell 100 , the service life of the battery 1000 is extended and the safety of the battery 1000 is improved.

[0080] The battery module 2000 according to the third embodiment of the present application includes the battery 1000 according to the second embodiment of the present application, as shown in FIG10 .

[0081] According to the battery module 2000 of the present application, by adopting the above-mentioned battery 1000, the service life of the battery module 2000 is extended and the safety of the battery module 2000 is improved.

[0082] The battery pack 3000 according to the fourth embodiment of the present application includes the battery 1000 according to the second embodiment of the present application or the battery module 2000 according to the third embodiment of the present application, as shown in Figures 11 and 12.

[0083] According to the battery pack 3000 of the present application, by adopting the above-mentioned battery 1000 or the above-mentioned battery module 2000, the battery pack 3000 is prevented from being damaged, thereby extending the service life of the battery pack 3000, and the internal air pressure of the battery 1000 can be effectively released when it is too high, thereby improving the safety of the battery pack 3000.

[0084] The power-consuming device 4000 according to the fifth embodiment of the present application includes the battery pack 3000 according to the fourth embodiment of the present application, as shown in FIG13 .

[0085] According to the power consumption device 4000 of the present application, the performance of the power consumption device 4000 is improved by adopting the above-mentioned battery pack 3000. The power consumption device 4000 can be a vehicle, an electric two-wheeled vehicle, an electric multi-wheeled vehicle, an energy storage cabinet, a drone, a ship, etc.

[0086] Other structures and operations of the battery cell 100 , battery 1000 , battery module 2000 , battery pack 3000 and power-consuming device 4000 according to the embodiments of the present application are well known to those skilled in the art and will not be described in detail here.

[0087] In the description of this application, it should be understood that the terms "center", "length", "thickness", "up", "down", "inside", "outside", "axial", "radial", "circumferential", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on this application.

[0088] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "example," "specific example," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0089] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and intent of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A battery cell (100), characterized in that, Comprising: A housing (1); An electrode core (2), the electrode core (2) is disposed within the housing (1), the two ends of the electrode core (2) in the length direction are respectively a first end (21) and a second end (22), and a positive electrode tab (211) and a negative electrode tab (212) are provided at the first end (21); and A separator (3), the separator (3) is disposed within the housing (1), the separator (3) is located between the second end (22) of the electrode core (2) and the housing (1), and the separator (3) isolates the electrode core (2) from the housing (1).

2. The battery cell (100) according to claim 1, wherein, At least one through hole (31) that penetrates is formed on the separator (3).

3. The battery cell (100) according to claim 2, wherein, A pressure relief device (11) is provided on the housing (1), and the pressure relief device (11) is configured to be able to release the internal pressure of the battery cell (100).

4. The battery cell (100) according to claim 3, characterized in that, The housing (1) includes a housing body (120) and a bottom cover plate (12) connected to each other, the separator (3) isolates the electrode core (2) from the bottom cover plate (12), and the pressure relief device (11) is provided on the bottom cover plate (12).

5. The battery cell (100) according to claim 3 or 4, characterized in that, At least a part of the pressure relief device (11) is opposite to the through hole (31) along the thickness direction of the separator (3).

6. The battery cell (100) according to claim 5, characterized in that, The area of the overlap of the projection of at least a part of the pressure relief device (11) on the separator (3) along the thickness direction of the separator (3) and the through hole (31) is S1, and the cross-sectional area of the pressure relief device (11) cut along a plane perpendicular to the thickness direction of the separator (3) is S2, wherein S1 and S2 satisfy: 50% ≤ S1 / S2 ≤ 100%.

7. The battery cell (100) according to any one of claims 2-6, characterized in that, The cross-sectional area of the through hole (31) cut along a plane perpendicular to the thickness direction of the separator (3) is S3, and the cross-sectional area of the separator (3) cut along a plane perpendicular to the thickness direction of the separator (3) is S4, wherein S3 and S4 satisfy: 30% ≤ S3 / S4 ≤ 80%.

8. The battery cell (100) according to any one of claims 2-7, characterized in that, The through holes (31) are multiple, and the multiple through holes (31) form at least one first through hole group (32) and at least one second through hole group (33), the first through hole group (32) includes multiple first through holes (321), the multiple first through holes (321) are spaced apart along the radial direction of the separator (3), the second through hole group (33) includes multiple second through holes (331), the multiple second through holes (331) are spaced apart along the circumferential direction of the separator (3), and the multiple second through holes (331) and the multiple first through holes (321) are spaced apart from each other.

9. The battery cell (100) according to claim 8, characterized in that, The cross-sectional area of the second through hole (331) cut along a plane perpendicular to the thickness direction of the separator (3) is larger than the cross-sectional area of the first through hole (321) cut along a plane perpendicular to the thickness direction of the separator (3).

10. The battery cell (100) according to claim 8 or 9, characterized in that, The cross-sectional areas of the multiple first through holes (321) cut along a plane perpendicular to the thickness direction of the separator (3) are all the same; or The cross-sectional areas of at least two of the plurality of the first through holes (321) cut along a plane perpendicular to the thickness direction of the separator (3) are different.

11. The battery cell (100) according to any one of claims 8-10, characterized in that, There are a plurality of the first through hole groups (32), and the plurality of the first through hole groups (32) are arranged at intervals along the circumferential direction of the separator (3), and the second through hole (331) is located between two adjacent first through hole groups (32).

12. The battery cell (100) according to any one of claims 8-11, characterized in that, The minimum distance between any one of the second through holes (331) and the first through hole (321) adjacent to the first through hole group (32) near the edge of the separator (3) is l1, where l1 satisfies: 0.5 mm ≤ l1 ≤ 3 mm; and / or The minimum distance between two adjacent first through holes (321) adjacent to the edge of the separator (3) in the first through hole group (32) is l2, where l2 satisfies: 0.5 mm ≤ l2 ≤ 3 mm.

13. The battery cell (100) according to any one of claims 1-12, characterized in that, The thickness of the separator (3) is h, where h satisfies: 0.3 mm ≤ h ≤ 2 mm.

14. The battery cell (100) according to any one of claims 1-13, characterized in that, The separator (3) is a polyethylene terephthalate part or a polypropylene part.

15. A battery (1000), characterized in that, It includes the battery cell (100) according to any one of claims 1-14.

16. A battery module (2000), characterized in that, It includes the battery (1000) according to claim 15.

17. A battery pack (3000), characterized in that, It includes the battery (1000) according to claim 15 or the battery module (2000) according to claim 16.

18. An electrical device (4000), characterized in that, It includes the battery pack (3000) according to claim 17.

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