Battery cell, battery pack and electrical device

Abstract

A battery cell, comprising a housing and an electrode core, an accommodating cavity being formed in the housing, and a pole being arranged at one end of the housing and insulated from the housing. The electrode core is mounted in the accommodating cavity, and is provided with a first tab and a second tab. The first tab is conductively connected to the pole, and the second tab is electrically connected to the housing. The thickness of the first tab is H1, and the thickness of the second tab is H2. The circle where the position from which the first tab extends is located is a first circle, and the circle where the position from which the second tab extends is located is a second circle, the first circle and the second circle being concentrically arranged. The radius of the first circle is r1, the radius of the second circle is r2, and the following relationship is satisfied: π*(H1*r1+H2*r2)≥6.6 mm2.

Description

Battery cells, battery packs and electrical equipment

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on the Chinese patent application with application number 202311438259.X and application date October 31, 2023, and claims the priority of the above-mentioned Chinese patent application. The entire content of the above-mentioned Chinese patent application is hereby introduced into this application as a reference. Technical Field

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

[0004] In related technology, a cylindrical battery consists of a core and a housing. A positive electrode sheet and a negative electrode sheet are located at the same end of the core, symmetrically arranged radially about the core. The housing is provided with a post. The positive electrode sheet is electrically connected to the housing via a busbar, while the negative electrode sheet is electrically connected to the post via a busbar and separated from the positive electrode sheet by an insulating sheet. Due to size limitations, the positive and negative electrode sheets are typically small, making them susceptible to heat collection due to insufficient flow area, which can damage the cylindrical battery.

[0005] Application Contents

[0006] The present application aims to solve one of the technical problems in the related art at least to a certain extent.

[0007] To this end, one purpose of the present application is to provide a battery cell with good current capacity, which can prevent heat accumulation and has a long service life.

[0008] According to an embodiment of the present application, a battery cell includes: a shell having an accommodating cavity formed therein, and a pole is provided at one end of the shell, the pole and the shell being insulated; a pole core, the pole core being installed in the accommodating cavity, and a first pole tab and a second pole tab being provided at one end of the pole core corresponding to the pole, the first pole tab being conductively connected to the pole, the second pole tab being conductively connected to the shell, the thickness of the first pole tab being H1, the thickness of the second pole tab being H2, the circle where the first pole tab extends is the first circle, the circle where the second pole tab extends is the second circle, the first circle and the second circle are concentrically arranged, the radius of the first circle is r1, and the radius of the second circle is r2, and the battery cell satisfies: π*(H1*r1+H2*r2)≥6.6mm 2 .

[0009] According to the battery cells of the embodiments of the present application, by setting the battery cells to satisfy the above relationship, the battery cells can have good current flow capacity, avoid heat collection due to insufficient current flow area, and increase the service life of the battery cells.

[0010] According to the battery cells of some embodiments of the present application, the first pole tab is a multi-layer structure, the thickness of a single layer of the first pole tab is e1, the number of layers of the first pole tab is d1, and the thickness of the first pole tab H1 = e1*d1; and / or the second pole tab is a multi-layer structure, the thickness of a single layer of the second pole tab is e2, the number of layers of the second pole tab is d2, and the thickness of the first pole tab H2 = e2*d2.

[0011] According to the battery cells of some embodiments of the present application, the value range of d1 is 5 to 30, and / or the value range of d2 is 5 to 30.

[0012] According to the battery cell of some embodiments of the present application, when the first tab is a negative electrode, the battery cell satisfies: π*H1*r1≥2.6mm 2 ; or when the first tab is a positive electrode, the battery cell satisfies: π*H1*r1≥4mm 2 .

[0013] According to the battery cells of some embodiments of the present application, the pole core is formed with a winding center hole, the protruding position of the first pole tab is located radially outside the winding center hole, and the first pole tab at least partially covers the winding center hole.

[0014] According to the battery cell of some embodiments of the present application, the radius of the winding center hole is r, the extension length of the first electrode tab is L1, and the following conditions are satisfied: r1-0.5r≤L1≤r+r1.

[0015] According to the battery cell of some embodiments of the present application, the radius of the winding center hole is r, satisfying: r1≥2r.

[0016] According to some embodiments of the present application, the battery cell further includes: a current collecting plate, which is clamped between the shell and the end of the pole core, the first pole ear is located on the side of the second pole ear close to the center of the pole core, and an avoidance through-hole is formed in the middle of the current collecting plate, the first pole ear is passed through the avoidance through-hole and is conductively connected to the pole column, and the current collecting plate is conductively connected to the second pole ear and the shell respectively.

[0017] According to the battery cells of some embodiments of the present application, the first side wall of the current collecting plate is provided with a connecting protrusion protruding toward the shell, and the connecting protrusion is conductively connected to the shell.

[0018] According to the battery cells of some embodiments of the present application, an escape space is provided between the first side wall of the current collecting plate and the inner wall of the shell, the current collecting plate is provided with a through hole, and the second pole tab extends into the escape space through the through hole and is conductively connected to the first side wall.

[0019] According to the battery cell of some embodiments of the present application, the portion of the second electrode tab that is conductively connected to the first side wall is located on a side of the through hole that is away from the center of the electrode core.

[0020] According to the battery cell of some embodiments of the present application, the radius of the pole core is R, the thickness of the collecting plate is D, and the extension length of the second pole tab is L2, which satisfies: 3.5 mm ≤ L2 ≤ R-r2+D.

[0021] According to the battery cells of some embodiments of the present application, the protruding height of the connecting protrusion is f, which satisfies: f≥H2+0.5mm.

[0022] According to the battery cells of some embodiments of the present application, the thickness of the connecting protrusion is 2 mm to 3 mm.

[0023] According to some embodiments of the present application, the battery cell further includes an insulating spacer, which is provided between the first electrode tab and the avoidance through-hole to insulate and separate the first electrode tab from the current collecting plate.

[0024] According to the battery cells of some embodiments of the present application, the radius of the avoidance through hole is r3, satisfying: r1+g≤r3≤r2-k; wherein, 2mm≤g≤3mm, 2mm≤k≤5mm.

[0025] According to the battery cells of some embodiments of the present application, there are multiple first pole tabs and they are spaced apart along the circumference of the pole core, and there are multiple second pole tabs and they are spaced apart along the circumference of the pole core.

[0026] According to the battery cells of some embodiments of the present application, the curvature of each of the first pole tabs ranges from 0.35 rad to 0.45 rad; and / or the curvature of each of the second pole tabs ranges from 0.35 rad to 0.45 rad.

[0027] This application also proposes a battery pack.

[0028] A battery pack according to an embodiment of the present application includes: a battery cell according to any of the above embodiments and a housing, wherein the battery cell is disposed in the housing.

[0029] The present application further proposes an electrical device.

[0030] According to an embodiment of the present application, the electric device includes: a battery pack according to any of the above embodiments or a battery cell according to any of the above embodiments, and an electric main body, wherein the battery pack or the battery cell is arranged in the electric main body.

[0031] The advantages of the battery pack, the electrical equipment and the battery cell compared to the prior art are the same and will not be described in detail here.

[0032] 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

[0033] FIG1 is a cross-sectional view 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 pole core according to an embodiment of the present application;

[0036] FIG4 is a schematic diagram of the installation of the pole core and the current collecting plate according to an embodiment of the present application;

[0037] FIG5 is a schematic diagram of an electrical device according to an embodiment of the present application;

[0038] FIG6 is a schematic diagram of an electrical device according to another embodiment of the present application.

[0039] Reference numerals:

[0040] Battery pack 1000, power-consuming entity 2000, power-consuming equipment 3000,

[0041] Battery cell 100, housing 200,

[0042] Shell 1, main body 11, welding groove 111, cover 12, pole 13, accommodating cavity 14,

[0043] Pole core 2, first pole ear 21, second pole ear 22, winding center hole 23,

[0044] The collecting plate 3 , the first side wall 3 a , the avoidance through hole 31 , the connecting protrusion 32 , the through hole 33 , the avoidance space 4 , the insulating spacer 5 , and the insulating sleeve 6 . DETAILED DESCRIPTION

[0045] The following describes in detail embodiments of the present application, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0046] Hereinafter, a battery cell 100 according to an embodiment of the present application will be described with reference to the accompanying drawings.

[0047] As shown in Figures 1 to 5, a battery cell 100 according to an embodiment of the present application includes: a shell 1 and a pole core 2, a housing 14 is formed in the shell 1, and a pole post 13 is provided at one end of the shell 1, and the pole post 13 is insulated from the shell 1; the pole core 2 is installed in the housing 14, and a first pole tab 21 and a second pole tab 22 are provided at one end of the pole core 2 corresponding to the pole post 13, the first pole tab 21 is conductively connected to the pole post 13, and the second pole tab 22 is conductively connected to the shell 1, the thickness of the first pole tab 21 is H1, the thickness of the second pole tab 22 is H2, the circle where the first pole tab 21 extends is the first circle, and the circle where the second pole tab 22 extends is the second circle, the first circle and the second circle are concentrically arranged, the radius of the first circle is r1, and the radius of the second circle is r2, and the battery cell 100 satisfies: π*(H1*r1+H2*r2)≥6.6mm 2 .

[0048] As a result, the battery cell 100 can have a good flow capacity, avoid heat collection due to insufficient flow area, and increase the service life of the battery cell 100.

[0049] For example, referring to Figures 1 to 4, the battery cell 100 includes a shell 1, which includes a main body 11 and a cover portion 12. The main body 11 is constructed in a cylindrical shape, and the main body 11 forms a accommodating cavity 14 with an open end. The cover portion 12 is covered on the main body 11 and is used to close the open end of the accommodating cavity 14. The other end of the main body 11 is provided with a pole 13, which penetrates the main body 11 axially and is insulated from the main body 11 by an insulating sleeve 6. One of the pole 13 and the shell 1 leads to the positive electrode and the other leads to the negative electrode.

[0050] The battery cell 100 further includes a core 2, which is configured to mate with the housing 14 and is intended to be mounted within the housing 14. A first tab 21 and a second tab 22 are provided at one end of the core 2 corresponding to the terminal post 13. One of the first tab 21 and the second tab 22 is a positive tab, and the other is a negative tab. The first tab 21 extends (i.e., protrudes from the surface of the core 2) within a first circle extending circumferentially along the core 2. The first tab 21 is configured to electrically connect to the terminal post 13. The second tab 22 extends within a second circle extending circumferentially along the core 2. The second tab 22 is configured to electrically connect to the housing 1, thereby causing one of the terminal post 13 and the housing 1 to be negatively charged and the other to be positively charged. Specifically, the second circle can be positioned radially outward of the first circle, radially inward of the first circle, or radially overlapped with the first circle. This is not a limitation of the present application.

[0051] The thickness of the first tab 21 can be set to H1, the thickness of the second tab 22 can be set to H2, the radius of the first circle can be set to r1, and the radius of the second circle can be set to r2. The battery cell 100 satisfies: π*(H1*r1+H2*r2)≥6.6mm 2 Here, it should be noted that the radius of the first circle and the second circle refers to the radius from the center of the circle where the extension position is located to the inner side of the corresponding tab, wherein the inner side is the side surface of the tab facing the center of the pole core 2.

[0052] Specifically, according to Joule's law, formula I is calculated 2 R1t = cmΔT, R1 = ρL / s; where R1 is the tab resistance, t is the charging time, c is the specific heat capacity, m is the mass, ΔT is the temperature rise, and ρ is the resistivity. cAluminum = 880J / kg / °C, cCopper = 390J / kg / °C; ρAluminum = 2.83×10-5Ω·mm, ρCopper = 1.75×10-5Ω·mm. Battery cell 100 must meet a 1C fast charge current of I = 15A. Calculation yields the following relationship to meet this overcurrent capability: π*(H1*r1+H2*r2)≥6.6mm 2 .

[0053] It can be understood that since the first tab 21 and the second tab 22 are ring-shaped structures and the number of tabs is small, the sum of the product of the thickness H1 of the first tab 21 and the radius r1 of the first circle plus the product of the thickness H1 of the second tab 22 and the radius r2 of the second circle is set to be greater than or equal to 6.6 mm. 2 , the battery cell 100 can have good current-carrying capacity, avoid heat collection caused by insufficient current-carrying area, and increase the service life of the battery cell 100.

[0054] According to the battery cell 100 of the embodiment of the present application, by setting the battery cell 100 to satisfy the above relationship, the battery cell 100 can have good current flow capacity, avoid heat collection due to insufficient flow area, and increase the service life of the battery cell 100.

[0055] In some embodiments of the present application, the first electrode tab 21 may be configured as a multi-turn electrode tab. The multi-turn first electrode tab 21 is sequentially arranged along the radial direction of the electrode core 2. The radii of the circles where the multi-turn first electrode tab 21 extends are r11, r12, r13, ..., respectively. The radius of the first circle where the first electrode tab 21 extends is r1 = (r11 + r12 + r13 + ...) / n. The second electrode tab 21 is similar and will not be further described here.

[0056] In some embodiments of the application, the first pole tab 21 is a multi-layer structure, the thickness of a single layer of the first pole tab 21 is e1, the number of layers of the first pole tab 21 is d1, and the thickness H1 of the first pole tab 21 is equal to e1*d1; and / or the second pole tab 22 is a multi-layer structure, the thickness of a single layer of the second pole tab 22 is e2, the number of layers of the second pole tab 22 is d2, and the thickness H2 of the first pole tab 21 is equal to e2*d2.

[0057] For example, the first pole tab 21 can be configured as a multi-layer structure, with a single layer thickness of e1 and a number of layers of d1. The thickness H1 of the first pole tab 21 is the product of the single layer thickness e1 and the number of layers d1. Simultaneously, the second pole tab 22 can be configured as a multi-layer structure, with a single layer thickness e2 and a number of layers d2. The thickness H2 of the second pole tab 22 is the product of the single layer thickness e2 and the number of layers d2. In this way, by adjusting the number of layers of the first and second pole tabs 21, 22, the thickness of the first and second pole tabs 21, 22 can be varied, thereby adjusting the current handling capacity of the battery cell 100. It should be noted that the greater the thickness of the first and second pole tabs 21, 22, the better the current handling capacity. This facilitates meeting different operating conditions.

[0058] In some embodiments of the present application, the value range of d1 is 5 to 30, and the value range of d2 is 5 to 30. For example, the number of layers d1 of the first electrode tab 21 can be 10, or the number of layers d1 of the first electrode tab 21 can be 15, or the number of layers d1 of the first electrode tab 21 can be 25, and this application does not impose any restrictions on this; the number of layers d2 of the second electrode tab 22 can be 10, or the number of layers d2 of the second electrode tab 22 can be 15, or the number of layers d2 of the second electrode tab 22 can be 25, and this application does not impose any restrictions on this.

[0059] The above arrangement can avoid undesirable situations such as tab breakage during welding due to too few layers, and can also avoid difficulty in installing the tabs due to too many layers, thereby improving the design rationality of the battery cell 100.

[0060] In some embodiments of the present application, when the first tab 21 is a negative electrode, the battery cell 100 satisfies: π*H1*r1≥2.6mm 2 ; Or when the first tab 21 is the positive electrode, the battery cell 100 satisfies: π*H1*r1≥4mm 2 Specifically, the first tab 21 can be set as the negative electrode, and the second tab 22 can be set as the positive electrode. In this case, the battery cell 100 satisfies: π*H1*r1≥2.6mm 2 ,π*H2*r2≥4mm 2 Alternatively, the first tab 21 may be set as the positive electrode, and the second tab 22 may be set as the negative electrode. In this case, the battery cell 100 satisfies: π*H1*r1≥2.6mm 2 ,π*H2*r2≥4mm 2 Through the above configuration, it is possible to ensure that both the first electrode tab 21 and the second electrode tab 22 have sufficient current capacity, which is beneficial to improving the reliability of the battery cell 100 .

[0061] In some embodiments of the present application, the pole core 2 is formed with a winding center hole 23, the protruding position of the first pole tab 21 is located radially outside the winding center hole 23, and the first pole tab 21 at least partially covers the winding center hole 23. For example, referring to Figures 1 to 4, the pole core 2 is wound, the winding center hole 23 is formed in the middle of the pole core 2, the pole post 13 is arranged opposite the winding center hole 23, the first pole tab 21 is located radially outside the winding center hole 23, the first pole tab 21 is tilted inward to extend toward the winding center hole 23, so that the winding center hole 23 is covered by at least a portion of the first pole tab 21, and the portion of the first pole tab 21 covering the winding center hole 23 is opposite to the pole post 13 and is used to be welded to the pole post 13 to achieve a conductive connection between the first pole tab 21 and the pole post 13.

[0062] Through the above-mentioned arrangement, the first pole ear 21 can be positioned to ensure that the first pole ear 21 can contact the pole post 13 after the pole core 2 is loaded into the accommodating cavity 14, thereby improving the connection reliability between the pole post 13 and the first pole ear 21. During the welding process, the welding head needle can extend from the other end of the pole core 2 through the winding center hole 23 to the first pole ear 21 for welding, which is conducive to reducing the difficulty of welding and improving the design rationality of the battery cell 100.

[0063] In some embodiments of the present application, the radius of the winding center hole 23 is r, and the extension length of the first electrode tab 21 is L1, which satisfies: r1-0.5r≤L1≤r+r1.

[0064] For example, as shown in FIG1 and FIG3 , the radius of the first circle where the first tab 21 extends can be set to r1, the radius of the winding center hole 23 can be set to r, and the extended length of the first tab 21 can be set to L1, satisfying the following: r1-0.5r≤L1≤r+r1. In other words, the extended length L1 of the first tab 21 can be set to be greater than or equal to the difference between the radius r1 of the first circle and 0.5 times the radius r of the winding center hole 23, so that the first tab 21 and the winding center hole 23 have an overlap dimension of at least 0.5r. The extended length L1 of the first tab 21 can be set to be less than or equal to the sum of the radius r1 of the first circle and the radius r of the winding center hole 23, so that the first tab 21 and the winding center hole 23 have an overlap dimension of exactly 2r.

[0065] Through the above arrangement, it is possible to ensure that the first pole tab 21 and the winding center hole 23 have sufficient overlapping area to improve the connection stability between the first pole tab 21 and the pole 13, and to avoid the first pole tab 21 being too long, which is beneficial to saving materials, facilitating layout, and improving the reliability of the battery cell 100.

[0066] In some embodiments of the present application, the radius of the first circle is set to r1, and the radius of the winding center hole 23 is set to r, satisfying the following: r1 ≥ 2r. This allows for sufficient spacing between the first tab 21 and the winding center hole 23, ensuring that the first tab 21 has sufficient bending space to fit onto the end surface of the electrode core 2, thereby covering the winding center hole 23. This improves the design rationality of the battery cell 100.

[0067] In some embodiments of the present application, the battery cell 100 of the embodiments of the present application further includes: a current collecting plate 3, which is clamped between the shell 1 and the end of the pole core 2, and the first pole ear 21 is located on the side of the second pole ear 22 close to the center of the pole core 2. An avoidance through-hole 31 is formed in the middle of the current collecting plate 3, and the first pole ear 21 is passed through the avoidance through-hole 31 and is conductively connected to the pole column 13. The current collecting plate 3 is conductively connected to the second pole ear 22 and the shell 1 respectively.

[0068] For example, referring to Figures 1 and 2, the battery cell 100 further includes a current collecting plate 3, which is sandwiched between the housing 1 and the end of the pole core 2. The first pole tab 21 is located on the side of the second pole tab 22 close to the center of the pole core 2. A relief hole 31 is provided in the middle of the current collecting plate 3. The two ends of the relief hole 31 are respectively opposite to the pole post 13 and the first pole tab 21. The first pole tab 21 is insulated and inserted into the relief hole 31 and welded to the pole post 13. For example, the first pole tab 21 and the pole post 13 can be connected by ultrasonic welding to achieve a conductive connection between the first pole tab 21 and the pole post 13. It is understandable that the first pole tab 21 needs to be insulated and inserted into the relief hole 31 to avoid short circuit between the first pole tab 21 and the current collecting plate 3. For example, the first pole tab 21 does not contact the inner wall of the relief hole 31, or an insulating member is provided between the first pole tab 21 and the relief hole 31. The current collecting plate 3 is arranged opposite to the second electrode tab 22 and is welded to the second electrode tab 22. The current collecting plate 3 can be welded to the end surface of the housing 1 so that the second electrode tab 22 can be electrically connected to the housing 1 through the current collecting plate 3. It should be noted that the housing 1 and the current collecting plate 3 can be welded by penetration welding.

[0069] It is understood that by arranging the second pole tab 22 on the side of the first pole tab 21 facing away from the center of the pole core 2, the pole post 13 will not be electrically connected to the second pole tab 22 at any installation angle, thereby preventing short circuits, reducing the difficulty of assembling the pole core 2, and improving the yield rate of the battery cell 100. In addition, by arranging the first pole tab 21 to be directly electrically connected to the pole post 13 and the second pole tab 22 to be electrically connected to the housing 1 through the current collecting plate 3, the number of parts is reduced, the difficulty of installation is reduced, and the yield rate of the battery cell 100 is improved.

[0070] In some embodiments of the present application, the first side wall 3a of the current collecting disc 3 is provided with a connecting protrusion 32 protruding toward the shell 1, and the connecting protrusion 32 is conductively connected to the shell 1. For example, referring to Figures 1 to 4, the side wall of the current collecting disc 3 facing the shell 1 can be set as the first side wall 3a, and the first side wall 3a is provided with a connecting protrusion 32. The connecting protrusion 32 is constructed as an annular structure, and the connecting protrusion 32 is arranged along the circumference of the current collecting disc 3 and protrudes toward the shell 1. When the pole core 2 is installed in the accommodating cavity 14, the connecting protrusion 32 can stop on the inner wall of the shell 1 and be welded to the shell 1 to achieve a conductive connection between the current collecting disc 3 and the shell 1. In this way, large-area contact between the current collecting disc 3 and the shell 1 can be avoided, which is conducive to improving the connection stability between the current collecting disc 3 and the shell 1.

[0071] Furthermore, as shown in Figure 2 , the connecting protrusions 32 may be arranged to extend along the inner edge of the current collecting plate 3. This helps to simplify the structure of the current collecting plate 3 and reduces the difficulty of processing the current collecting plate 3.

[0072] In the actual arrangement, as shown in Figures 1 and 2, a welding groove 111 can be provided on the side of the shell 1 away from the accommodating cavity 14. The welding groove 111 is constructed in a ring shape and is arranged opposite to the connecting protrusion 32. When the pole core 2 is installed in the accommodating cavity 14, the collecting plate 3 can be penetrated and welded at the welding groove 111 to achieve the connection between the shell 1 and the collecting plate 3.

[0073] In some embodiments of the present application, an escape space 4 is provided between the first side wall 3a of the collecting plate 3 and the inner wall of the shell 1, and the collecting plate 3 is provided with a through hole 33. The second pole ear 22 extends into the escape space 4 through the through hole 33 and is conductively connected to the first side wall 3a.

[0074] For example, as shown in Figures 1 and 2, the first side wall 3a of the current collecting tray 3 is spaced apart from the inner wall of the housing 1 and together define an escape space 4. A through hole 33 is provided on the current collecting tray 3 corresponding to the escape space 4. The through hole 33 is matched with the second pole tab 22, so that the second pole tab 22 can extend into the escape space 4 from the side of the current collecting tray 3 facing the pole core 2 through the through hole 33. The second pole tab 22 is suitable for falling radially inward or outward on the first side wall 3a of the current collecting tray 3 and being welded to the current collecting tray 3 to achieve a conductive connection between the current collecting tray 3 and the second pole tab 22. Through the above arrangement, the difficulty of welding between the current collecting tray 3 and the second pole tab 22 can be reduced, welding quality inspection can be facilitated, and the occurrence of cold welding and leaking welding can be prevented, thereby improving the quality of the battery cell 100.

[0075] In some embodiments of the present application, the portion of the second tab 22 electrically connected to the first sidewall 3a is located on the side of the through-hole 33 facing away from the center of the core 2. For example, as shown in FIG4 , the second tab 22 can be configured to fall radially outward, so that the portion electrically connected to the first sidewall 3a is located on the side of the through-hole 33 facing away from the center of the core 2. This prevents the second tab 22 from falling inward and contacting the first tab 21, and allows the second tab 22 to extend closer to the center of the core 2, thereby shortening the current path. This improves the practicality of the battery cell 100.

[0076] In some embodiments of the present application, the radius of the electrode core 2 is R, which can generally be 15 mm to 40 mm. The thickness of the current collecting plate 3 is D. The extended length of the second electrode tab 22 is L2, satisfying the following: 3.5 mm ≤ L2 ≤ R - r2 + D. For example, as shown in Figures 1 and 2, the radius of the second circle where the second electrode tab 22 extends is r2, the radius of the electrode core 2 is R, the thickness of the current collecting plate 3 is D, and the extended length of the second electrode tab 22 is L2, satisfying the following: 3.5 mm ≤ L2 ≤ R - r2 + D. In other words, the extended length L2 of the second electrode tab 22 is greater than or equal to 3.5 mm, ensuring sufficient contact area between the second electrode tab 22 and the current collecting plate 3, thereby reducing the overall resistance of the battery cell 100. It is also less than or equal to the total value of the radius R of the electrode core 2 minus the radius of the second circle plus the thickness of the current collecting plate 3. This prevents the second electrode tab 22 from extending radially outward from the electrode core 2 after being collapsed, thereby preventing the second electrode tab 22 from interfering with the installation process. As a result, the reliability of the battery cell 100 is improved.

[0077] In some embodiments of the present application, the radius of the electrode core 2 can be set to R, and the radius of the winding center hole 23 can be set to r, satisfying the following: r2 ≤ R-2r. In other words, the radius of the second circle can be set to be less than or equal to the radius of the electrode core 2 minus twice the radius of the winding center hole 23. This can prevent the spacing between the second electrode tab 22 and the winding center hole 23 from being too large. This helps shorten the current path and improves the current handling capacity of the battery cell 100.

[0078] In some embodiments of the present application, the protruding height of the connecting protrusion 32 can be set to f, satisfying: f ≥ H2 + 0.5 mm. For example, as shown in FIG1 , the protruding height of the connecting protrusion 32 can be set to f, and the thickness of the second pole tab 22 can be set to h, satisfying: f ≥ h + 0.5 mm, that is, the difference between the protruding height of the connecting protrusion 32 and the thickness of the second pole tab 22 is greater than or equal to 0.5 mm, such as 0.6 mm, 0.8 mm or 1 mm, and this application does not impose any restrictions on this. In this way, when the second pole tab 22 falls on the first side wall 3a, the side of the second pole tab 22 facing the shell 1 can maintain a distance from the shell 1 to prevent poor contact between the connecting protrusion 32 and the shell 1, thereby ensuring the connection reliability between the connecting protrusion 32 and the shell 1. As a result, the overall quality of the battery cell 100 is improved.

[0079] In some embodiments of the present application, as shown in FIG2 , the connecting protrusion 32 can be configured as a circular ring or a rectangular ring, and the thickness of the connecting protrusion 32 can be set to 2 mm to 3 mm, such as 2.1 mm, 2.2 mm, 2.3 mm, etc., where the thickness refers to the wall thickness of the connecting protrusion 32 in the direction from the center to the outside of the current collecting plate 3. Through the above configuration, the connecting protrusion 32 can have sufficient structural strength, which is beneficial to improving the reliability of the current collecting plate 3. The connecting protrusion 32 can also have a sufficient contact area with the housing 1, which is beneficial to improving the connection stability between the connecting protrusion 32 and the housing 1, reducing the resistance of the battery cell 100, and improving the reliability of the battery cell 100.

[0080] In some embodiments of the present application, the radius of the avoidance hole 31 can be set to r3, satisfying the following: r1+g≤r3≤r2-k; where 2mm≤g≤3mm, and 2mm≤k≤5mm. For example, the parameter g can be set to 2.5mm, so that the radius r3 of the avoidance hole 31 is greater than or equal to the sum of the radius r1 of the first circle plus 2.5mm, so that the inner wall of the avoidance hole 31 can maintain a sufficient distance from the first tab 21, thereby preventing the first tab 21 from being electrically connected to the current collecting plate 3. The parameter k can be set to 3.5mm, so that the radius r3 of the avoidance hole 31 is less than or equal to the difference between the radius r2 of the second circle minus 3.5mm, so that there is sufficient distance between the edge of the avoidance hole 31 and the second tab 22 to reserve sufficient processing space for the through hole 33. In this way, the reliability of the battery cell 100 can be improved.

[0081] Furthermore, as shown in Figures 1 and 2, the battery cell 100 also includes an insulating spacer 5, which is sandwiched between the end of the pole core 2 and the housing 1. The insulating spacer 5 is used to insulate the first pole tab 21 from the current collecting plate 3 to prevent conductive connection between the first pole tab 21 and the second pole tab 22. This improves the reliability of the battery cell 100.

[0082] In some embodiments of the present application, there are multiple first pole tabs 21 and they are spaced apart along the circumference of the pole core 2, and there are multiple second pole tabs 22 and they are spaced apart along the circumference of the pole core 2. For example, as shown in Figures 1, 3, and 4, there can be multiple first pole tabs 21, and the extension positions of the multiple first pole tabs 21 are all located on the first circle. The multiple first pole tabs 21 are spaced apart along the first circle and are used to be conductively connected to the pole post 13. At the same time, there can be multiple second pole tabs 22, and the extension positions of the multiple second pole tabs 22 are all located on the second circle. The multiple first pole tabs 21 are spaced apart along the second circle and are used to be conductively connected to the current collecting plate 3 respectively. Through the above arrangement, the resistance of the battery cell 100 can be reduced, which is conducive to improving the practicality of the battery cell 100.

[0083] In some embodiments of the present application, the radian of each first pole tab 21 is in the range of 0.35 rad to 0.45 rad; and / or the radian of each second pole tab 22 is in the range of 0.35 rad to 0.45 rad.

[0084] For example, as shown in Figures 1 to 4, the curvature of each first pole tab 21 can be set to a value range of 0.35 rad to 0.45 rad, such as the curvature of the first pole tab 21 can be set to 0.37 rad; or, the curvature of the first pole tab 21 can be set to 0.40 rad; or, the curvature of the first pole tab 21 can be set to 0.43 rad, and this application does not impose any restrictions on this. At the same time, the curvature of each second pole tab 22 can be set to a value range of 0.35 rad to 0.45 rad, such as the curvature of the second pole tab 22 can be set to 0.37 rad; or, the curvature of the second pole tab 22 can be set to 0.40 rad; or, the curvature of the second pole tab 22 can be set to 0.43 rad, and this application does not impose any restrictions on this.

[0085] Through the above arrangement, the first and second tabs 21 and 22 can have appropriate curvatures to avoid the curvature being too small and difficult to weld, and to avoid the curvature being too large and causing the first and second tabs 21 and 22 to tear during the falling process, thereby improving the design rationality of the battery cell 100.

[0086] Specifically, the manufacturing steps of the battery cell 100 are as follows:

[0087] In the first step, the positive and negative electrodes of the battery cell 100 are laser die-cut to form tabs on the same side of the positive and negative electrodes. The size of the tabs is calculated based on the first tab 21, the second tab 22, the diaphragm, and the desired effect after actual winding.

[0088] In the second step, the positive and negative electrode sheets are wound together with the separator to form a core 2. The positive and negative electrode sheets are separated by the separator. The tabs of the positive and negative electrode sheets are located at the same end of the core 2, and the tabs are wound into a multi-layer cylindrical shape. It should be noted that the separator is arranged to protrude from both ends of the core 2 to completely separate the positive and negative electrode sheets.

[0089] In the third step, the tab portion is processed using a metal tool or laser die-cutting to form a plurality of first tabs 21 and a plurality of second tabs 22 at the same end of the pole core 2. The plurality of first tabs 21 are evenly distributed in a circular pattern, and the second tabs 22 are located on the side of the first tab 21 away from the center of the pole core 2, and the plurality of second tabs 22 are evenly distributed in a circular pattern. It should be noted that both the first tab 21 and the second tab 22 have multiple layers distributed in the radial direction.

[0090] In the fourth step, ultrasonic pre-welding is performed on the first and second pole tabs 21, 22, respectively, so that the first and second pole tabs 21, 22 form an integral structure. Multiple first pole tabs 21 are radially tilted toward the winding center hole 23 and stacked in sequence. The second pole tab 22 is inserted into the through hole 33 and extends to the side of the current collecting plate 3 facing away from the pole core 2. The second pole tab 22 can be tilted radially outward onto the first sidewall 3a of the current collecting plate 3. A low-intensity laser is then used to weld the second pole tab 22 to the current collecting plate 3. Next, an insulating spacer 5 can be placed on the end face of the pole core 2. The pole core 2 is then inserted into the accommodating cavity 14 from the open end, so that the first pole tab 21 abuts against the pole post 13. A welding needle is then inserted from the other end of the pole core 2 through the winding center hole 23. The welding needle is used to perform ultrasonic torque welding on the welding position of the first pole tab 21 and the pole post 13 to weld the first pole tab 21 and the pole post 13 together.

[0091] In the fifth step, the cover 12 and the main body 11 are assembled. After assembly, laser sealing welding is performed along the circumference of the cover 12 at the connection point between the cover and the main body 11. Through-welding is then performed between the housing 1 and the current collecting plate 3 through the welding grooves 111. This completes the processing of the battery cell 100.

[0092] This application also proposes a battery pack 1000 .

[0093] As shown in Figure 6, the battery pack 1000 according to an embodiment of the present application includes: a battery cell 100 according to any of the above embodiments and a shell 200, the battery cell 100 is arranged in the shell 200, and the shell 200 is used to protect the battery cell 100, so as to prevent the battery cell 100 from being directly impacted when the battery pack 1000 collides.

[0094] According to the battery pack 1000 of the embodiment of the present application, by setting the battery cell 100 to satisfy the above relationship, the battery cell 100 can have good current flow capacity, avoiding heat collection due to insufficient flow area, increasing the service life of the battery cell 100, and improving the practicality of the battery pack 1000.

[0095] This application also proposes an electrical device 3000.

[0096] As shown in Figures 5 and 6, an electric device 3000 according to an embodiment of the present application includes: a battery pack 1000 according to any of the above embodiments or a battery cell 100 according to any of the above embodiments, and an electric device 2000, wherein the battery pack 1000 or the battery cell 100 is disposed within the electric device 2000. For example, the electric device 2000 may be a new energy vehicle, a hybrid vehicle, an aircraft, an energy storage cabinet, or the like.

[0097] According to the electrical equipment 3000 of the embodiment of the present application, by setting the battery cell 100 to satisfy the above-mentioned relationship, the battery cell 100 can have good current flow capacity, avoiding heat collection due to insufficient current flow area, increasing the service life of the battery cell 100, improving the practicality of the battery pack 1000, and improving the overall performance of the electrical equipment 3000.

[0098] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present 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, and therefore should not be understood as a limitation on the present application.

[0099] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means more than two, unless otherwise specifically defined.

[0100] In this application, unless otherwise expressly specified or limited, terms such as "mounted," "connected," "connect," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components or interactions between two components. Those skilled in the art will understand the specific meanings of these terms in this application based on specific circumstances.

[0101] In this application, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0102] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0103] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A battery cell (100), wherein: include: A shell (1), wherein a receiving cavity (14) is formed in the shell (1), and a pole (13) is provided at one end of the shell (1), and the pole (13) and the shell (1) are insulated from each other; A pole core (2), the pole core (2) being installed in the accommodating cavity (14), the pole core (2) being provided with a first pole ear (21) and a second pole ear (22) at one end corresponding to the pole column (13), the first pole ear (21) being electrically connected to the pole column (13), the second pole ear (22) being electrically connected to the shell (1), the thickness of the first pole ear (21) being H1, the thickness of the second pole ear (22) being H2, the circle where the first pole ear (21) is located is a first circle, the circle where the second pole ear (22) is located is a second circle, the first circle and the second circle are arranged concentrically, the radius of the first circle is r1, and the radius of the second circle is r2, the battery cell (100) satisfies: π*(H1*r1+H2*r2)≥6.6mm 2 .

2. The battery cell (100) according to claim 1, wherein: The first pole lug (21) is a multi-layer structure, the thickness of a single layer of the first pole lug (21) is e1, the number of layers of the first pole lug (21) is d1, and the thickness of the first pole lug (21) is H1=e1*d1; and / or The second pole tab (22) is a multi-layer structure, the thickness of a single layer of the second pole tab (22) is e2, the number of layers of the second pole tab (22) is d2, and the thickness of the first pole tab (21) is H2=e2*d2.

3. The battery cell (100) according to claim 2, wherein: The value range of d1 is 5-30, and / or the value range of d2 is 5-30.

4. The battery cell (100) according to any one of claims 1 to 3, wherein: When the first pole lug (21) is a negative pole, the battery cell (100) satisfies: π*H1*r1≥2.6mm 2 ;or When the first pole lug (21) is a positive pole, the battery cell (100) satisfies: π*H1*r1≥4mm 2 .

5. The battery cell (100) according to any one of claims 1 to 4, wherein: The pole core (2) is formed with a winding center hole (23), the protruding position of the first pole lug (21) is located radially outside the winding center hole (23), and the first pole lug (21) at least partially covers the winding center hole (23).

6. The battery cell (100) according to claim 5, wherein: The radius of the winding center hole (23) is r, and the extension length of the first pole tab (21) is L1, satisfying the following: r1-0.5r≤L1≤r+r1.

7. The battery cell (100) according to claim 5 or 6, wherein: The radius of the winding center hole (23) is r, satisfying: r1≥2r.

8. The battery cell (100) according to any one of claims 1 to 7, wherein: The invention also comprises: a current collecting plate (3), wherein the current collecting plate (3) is sandwiched between the shell (1) and the end of the pole core (2), the first pole lug (21) is located on the side of the second pole lug (22) close to the center of the pole core (2), an avoidance through hole (31) is formed in the middle of the current collecting plate (3), the first pole lug (21) is passed through the avoidance through hole (31) and is conductively connected to the pole column (13), and the current collecting plate (3) is conductively connected to the second pole lug (22) and the shell (1) respectively.

9. The battery cell (100) according to claim 8, wherein: The first side wall (3a) of the current collecting plate (3) is provided with a connecting protrusion (32) protruding toward the shell (1), and the connecting protrusion (32) is electrically connected to the shell (1).

10. The battery cell (100) according to claim 9, wherein: An escape space (4) is provided between the first side wall (3a) of the current collecting disk (3) and the inner wall of the shell (1); the current collecting disk (3) is provided with a through hole (33); the second pole lug (22) extends into the escape space (4) through the through hole (33) and is conductively connected to the first side wall (3a).

11. The battery cell (100) according to claim 10, wherein: The portion of the second pole tab (22) that is electrically connected to the first side wall (3a) is located on a side of the through hole (33) that is away from the center of the pole core (2).

12. The battery cell (100) according to claim 11, wherein: The radius of the pole core (2) is R, the thickness of the current collecting disk (3) is D, and the extension length of the second pole ear (22) is L2, satisfying: 3.5 mm ≤ L2 ≤ R-r2+D.

13. The battery cell (100) according to claim 10 or 11, wherein: The protruding height of the connecting protrusion (32) is f, which satisfies: f≥H2+0.5mm.

14. The battery cell (100) according to any one of claims 10 to 13, wherein: The thickness of the connecting protrusion (32) is 2 mm to 3 mm.

15. The battery cell (100) according to any one of claims 8 to 14, wherein: It also comprises an insulating spacer (5), wherein the insulating spacer (5) is arranged between the first pole lug (21) and the avoidance through hole (31) so as to insulate and separate the first pole lug (21) from the current collecting plate (3).

16. The battery cell (100) according to any one of claims 8 to 15, wherein: The radius of the avoidance through hole (31) is r3, which satisfies: r1+g≤r3≤r2-k; wherein, 2mm≤g≤3mm, 2mm≤k≤5mm.

17. The battery cell (100) according to any one of claims 1 to 16, wherein: The first pole lugs (21) are multiple and are arranged at intervals along the circumference of the pole core (2), and / or the second pole lugs (22) are multiple and are arranged at intervals along the circumference of the pole core (2).

18. The battery cell (100) according to claim 17, wherein: The curvature of each of the first pole lugs (21) ranges from 0.35 rad to 0.45 rad; and / or The radian of each of the second pole tabs (22) ranges from 0.35 rad to 0.45 rad.

19. A battery pack (1000), wherein: include: According to the battery cell (100) and the housing (200) according to any one of claims 1 to 18, the battery cell (100) is arranged in the housing (200).

20. An electrical device (3000), wherein: include: According to the battery pack (1000) according to claim 19 or the battery cell (100) according to any one of claims 1 to 18, and an electricity-consuming entity (2000), the battery pack (1000) or the battery cell (100) is arranged in the electricity-consuming entity (2000).

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