Pole group and battery cell

Abstract

This utility model relates to the field of battery technology, and in particular to an electrode assembly and a battery cell. The electrode assembly has N tabs at its first axial end, where N ≥ 2. Some of the N tabs are designated as first tabs, and the remaining tabs as second tabs. The distance between the wall of the venting channel and the outer wall of the electrode assembly in the radial direction of the battery cell is D (in mm). The width of the tabs in the radial direction of the battery cell is W, where 4 mm ≤ W ≤ 0.5 × D. The distance between adjacent first and second tabs in the radial direction of the battery cell is M, where 1.5 mm ≤ M ≤ 10 mm. This utility model leads the positive and negative tabs out from the same side of the electrode assembly. After the battery cell is assembled, the flow does not need to pass through the large surface of the casing, effectively reducing the battery's internal resistance. It also improves the utilization rate of the internal space of the battery cell, increases the energy density of the battery cell, meets the power consumption and range requirements of devices, and ensures smooth welding of the tabs to the current collector, cover plate, or casing, avoiding interference between multiple tabs and ensuring the performance of the battery cell.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to an electrode assembly and a battery cell. Background Technology

[0002] Cylindrical batteries are characterized by high energy density and good rate performance, and are therefore widely used in mobile communication devices and portable electronic devices, as well as in large and medium-sized electric equipment such as electric vehicles, electric bicycles, and power tools.

[0003] In existing cylindrical batteries, after being wound and formed, the positive and negative tabs of the electrode assembly are respectively located on the two end faces of its axial direction. After the battery is assembled, the current will flow through the large surface of the battery casing, which will increase the internal resistance of the battery. At the same time, placing the battery tabs on both sides of the battery will occupy more internal space of the battery, reduce the utilization rate of the internal space of the battery, and result in low battery energy, which cannot meet the needs of electronic products or electric devices. Utility Model Content

[0004] In view of this, the purpose of this application is to provide a pole assembly and a battery cell to solve the problem that existing pole assemblies have tabs on both sides of the axial direction, which leads to increased internal resistance, low space utilization, and affects energy density, thus failing to meet the usage requirements of electrical products.

[0005] The first aspect of this utility model provides an electrode assembly, wherein an exhaust channel is provided at the center of the electrode assembly; the electrode assembly is provided with N electrode tabs at a first end in the axial direction, where N=2 or N>2, and a portion of the N electrode tabs are first electrode tabs, and the remaining electrode tabs are second electrode tabs, wherein the polarities of the first electrode tabs and the second electrode tabs are opposite. In the radial direction of the battery cell, the distance between the wall of the vent channel and the outer wall of the electrode assembly is D, in mm; in the radial direction of the battery cell, the width of the electrode tab is W, 4mm≤W≤0.5×D; In the radial direction of the cell, the distance between adjacent first and second tabs is M, where 1.5mm ≤ M ≤ 10mm.

[0006] Preferably, the tab is formed as an annular structure coaxially arranged with the exhaust channel, where W is the distance between the inner annular wall and the outer annular wall of the tab in the radial direction of the cell; N tabs are nested together.

[0007] Preferably, in the radial direction of the cell, the distance between the outermost tab and the outer wall of the electrode group is L1, where 0mm≤L1≤5mm.

[0008] Preferably, in the radial direction of the battery cell, the distance between the innermost tab and the wall of the exhaust channel is L2, where 0mm≤L2≤5mm.

[0009] Preferably, N is an even number.

[0010] Preferably, the number of the first electrode tabs is the same as the number of the second electrode tabs.

[0011] Preferably, the number of the first electrode tabs is different from the number of the second electrode tabs.

[0012] Preferably, when N≥2, the first electrode and the second electrode are arranged alternately in sequence, such that the second electrode is disposed between two adjacent first electrodes, and / or the first electrode is disposed between two adjacent second electrodes.

[0013] Preferably, the pole group is formed as a cylindrical structure, and the circumferential sidewalls of the pole group and the second end of the pole group opposite to the first end in the axial direction are not provided with pole tabs. The second aspect of this utility model provides a battery cell, including the electrode assembly described in any of the above technical solutions.

[0014] Compared with the prior art, the beneficial effects of this utility model are as follows: The electrode assembly of this invention has an exhaust channel at its center. The first end of the electrode assembly in the axial direction has N tabs, where N=2 or N>2. Some of the N tabs are designated as first tabs, and the remaining tabs as second tabs. This allows the positive and negative tabs to be drawn out from the same side of the electrode assembly. After the cells are assembled, the flow does not need to pass through the large surface of the casing, effectively reducing the battery's internal resistance, improving the utilization rate of the internal space of the cells, and increasing the energy density of the cells to meet the power consumption and range requirements of electronic products or electric devices. The distance between the wall of the exhaust channel and the outer wall of the electrode assembly in the radial direction of the cell is D (in mm). The width of the tabs in the radial direction of the cell is W, where 4mm≤W≤0.5×D. The distance between adjacent first and second tabs in the radial direction of the cell is M, where 1.5mm≤M≤10mm. This ensures that the tabs can be smoothly welded to the current collector, cover plate, or casing, and avoids interference between multiple tabs, guaranteeing the performance of the cells.

[0015] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the pole group provided in an embodiment of the present invention when N=2; Figure 2 An axial cross-sectional view of the pole assembly provided in an embodiment of this utility model when N=2; Figure 3 An axial cross-sectional view of the electrode assembly provided in this embodiment of the present invention when N=2 and the electrode tabs are spaced apart from the outer wall of the electrode assembly; Figure 4 An axial cross-sectional view of the electrode assembly provided in this embodiment of the present invention when N=2, with the electrode tabs spaced apart from the outer wall of the electrode assembly and from the wall of the exhaust channel. Figure 5 This is a schematic diagram of the pole assembly provided in an embodiment of the present invention when N > 2; Figure 6 A schematic diagram of the pole group provided in an embodiment of the present invention when N>2, and from another perspective; Figure 7 For along Figure 6 Cross-sectional view taken at point AA.

[0018] Icons: 10-Pole group; 101-Exhaust duct; 11-Pole tab; 111-First pole tab; 112-Second pole tab. Detailed Implementation

[0019] The following detailed embodiments are provided to help the reader gain a comprehensive understanding of the methods, apparatus, and / or systems described herein. However, various changes, modifications, and equivalents of the methods, apparatus, and / or systems described herein will be apparent after understanding the disclosure of this application. For example, the order of operations described herein is merely illustrative and is not limited to the order set forth herein; changes that will be apparent after understanding the disclosure of this application are possible, except for operations that must occur in a specific order. Furthermore, for clarity and brevity, descriptions of features known in the art may be omitted.

[0020] The features described herein may be implemented in different forms and should not be construed as being limited to the examples described herein. Rather, the examples described herein have been provided merely to illustrate some of the many feasible ways of implementing the methods, apparatus, and / or systems described herein that will be apparent upon understanding the disclosure of this application.

[0021] Throughout the specification, when an element (such as a layer, region, or substrate) is described as being "on" another element, "connected to" another element, "bonded to" another element, "on" another element, or "covering" another element, it may be directly "on" another element, "connected to" another element, "bonded to" another element, "on" another element, or "covering" another element, or there may be one or more other elements in between. In contrast, when an element is described as being "directly on" another element, "directly connected to" another element, "directly bonded to" another element, "directly on" another element, or "directly covering" another element, there may be no other elements in between.

[0022] As used herein, the term “and / or” includes any one of the relevant items listed and any combination of any two or more items.

[0023] Although terms such as “first,” “second,” and “third” may be used herein to describe individual components, assemblies, regions, layers, or parts, these components, assemblies, regions, layers, or parts are not limited by these terms. Rather, these terms are used only to distinguish one component, assembly, region, layer, or part from another. Therefore, without departing from the teachings of the examples described herein, the first component, assembly, region, layer, or part referred to as the second component, assembly, region, layer, or part may also be referred to as the second component, assembly, region, layer, or part.

[0024] For ease of description, spatial relation terms such as “above,” “upper,” “below,” and “lower” are used herein to describe the relationship between one element and another, as shown in the accompanying drawings. Such spatial relation terms are intended to include not only the orientation depicted in the drawings but also different orientations of the device during use or operation. For example, if the device in the drawings is flipped, an element described as being “above” or “upper” relative to another element will subsequently be “below” or “lower” relative to that other element. Therefore, the term “above” includes both “above” and “below” orientations depending on the spatial orientation of the device. The device may also be positioned in other ways (e.g., rotated 90 degrees or in other orientations), and the spatial relation terms used herein will be interpreted accordingly.

[0025] The terminology used herein is for the purpose of describing various examples only and is not intended to limit this disclosure. Unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. The terms “comprising,” “including,” and “having” enumerate the stated features, quantities, operations, components, elements, and / or combinations thereof, but do not exclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof.

[0026] Variations in the shapes shown in the accompanying drawings may occur due to manufacturing techniques and / or tolerances. Therefore, the examples described herein are not limited to the specific shapes shown in the accompanying drawings, but include changes in shape that may occur during manufacturing.

[0027] The features of the examples described herein can be combined in various ways that will be apparent upon understanding the disclosure of this application. Furthermore, although the examples described herein have a wide variety of constructions, other constructions are possible, as will be apparent upon understanding the disclosure of this application.

[0028] According to a first aspect of the present invention, an electrode assembly is provided. The specific structure of the pole group according to this embodiment will be described below.

[0029] Electrode group 10 can be formed by winding electrode sheets or stacking electrode sheets, such as Figures 1 to 7 As shown, the center of the electrode group 10 is provided with an exhaust channel 101, which runs through the electrode group 10 along the axial direction of the cell, making the exhaust channel 101 a through-hole structure. The electrode group 10 is provided with N tabs 11 at the first end in the axial direction, where N=2 or N>2 and N is a positive integer. Some of the tabs 11 are first tabs 111, and the remaining tabs 11 are second tabs 112. The first tabs 111 and the second tabs 112 have opposite polarities. One of the first tabs 111 and the second tabs 112 is used to lead out the positive electrode of the cell, and the other of the first tabs 111 and the second tabs 112 is used to lead out the negative electrode of the cell. In this way, the positive and negative tabs are led out from the same side in the axial direction of the electrode group 10, so that the cells do not need to flow through the large surface of the casing after being assembled, which can effectively reduce the internal resistance of the battery, improve the utilization rate of the internal space of the cell, improve the energy density of the cell, and meet the power consumption and range requirements of electronic products or electric devices.

[0030] Specifically, in this embodiment, such as Figures 1 to 7As shown, in the radial direction of the battery cell, the distance between the wall of the vent duct 101 and the outer wall of the electrode assembly 10 is D, in mm; in the radial direction of the battery cell, the width of the tab 11 is W, 4mm≤W≤0.5×D. The width W of the first tab 111 and the second tab 112 in the radial direction of the battery cell both satisfy 4mm≤W≤0.5×D. This avoids the tab 11 being too small, making it easy to weld to the outside of the tab 11 when welding it to the current collector, cover plate, or shell, and also avoids the tab 11 being too large, affecting the layout of other tabs 11 and preventing interference between multiple tabs 11. More specifically, as... Figures 1 to 7 As shown, in the radial direction of the cell, the distance between adjacent first tabs 111 and second tabs 112 is M, 1.5mm≤M≤10mm. This avoids the first tabs 111 and second tabs 112 from overlapping if the size of M is too small, and also avoids the tabs 11 from being too large, affecting the layout of the tabs 11 on the pole group 10, avoiding interference between multiple tabs 11, and ensuring the performance of the cell.

[0031] It should be noted that, in this embodiment, the axial direction is... Figures 2 to 4 and Figure 7 The vertical direction from the perspective of the radial direction is... Figures 2 to 4 and Figure 7 Horizontal direction from the perspective of viewpoint.

[0032] In a first optional embodiment, the first electrode 111 is a positive electrode 11 and the second electrode 112 is a negative electrode 11; in a second optional embodiment, the first electrode 111 is a negative electrode 11 and the second electrode 112 is a positive electrode 11.

[0033] In this embodiment, as Figures 1 to 7 As shown, the pole group 10 is formed into a cylindrical structure, and the circumferential sidewalls of the pole group 10 and the second end of the pole group 10 opposite to the first end in the axial direction are not provided with pole tabs 11.

[0034] In other alternative embodiments, the electrode assembly 10 may also be formed as a cuboid structure. When the electrode assembly 10 is formed as a cuboid structure, only one of the six faces of the electrode assembly 10 is provided with a tab 11.

[0035] Furthermore, the tab 11 is formed as a ring structure coaxially arranged with the exhaust channel 101. As described above, the width W of the tab 11 in the radial direction of the cell is the distance between the inner ring wall and the outer ring wall of the tab 11 in the radial direction of the cell. N ring-shaped tabs 11 are nested in a ring, and the axes of all the tabs 11 are collinear, which facilitates the design and layout of the tabs 11.

[0036] In this embodiment, as Figures 2 to 4 and Figure 7As shown, in the radial direction of the battery cell, among the N ring-shaped electrode tabs 11 arranged in a nested configuration, the distance between the outermost electrode tab 11 and the outer wall of the electrode group 10 is L1, where 0mm ≤ L1 ≤ 5mm. Specifically, as shown... Figure 2 As shown, L1=0mm; Figure 3 , Figure 4 and Figure 7 As shown, 0mm < L1 ≤ 5mm, which avoids damage to the tabs 11 when the electrode group 10 is inserted into the casing during cell assembly, and also avoids the size of L1 being too large and affecting the layout of the tabs 11 on the electrode group 10.

[0037] In this embodiment, as Figures 2 to 4 and Figure 7 As shown, in the radial direction of the battery cell, among the N ring-shaped tabs 11 arranged in a nested configuration, the distance between the innermost tab 11 and the wall of the exhaust channel 101 is L2, where 0mm ≤ L2 ≤ 5mm. Specifically, as shown... Figure 2 and Figure 3 As shown, L2 = 0 mm; Figure 4 and Figure 7 As shown, 0mm < L2 ≤ 5mm, thus avoiding the tab 11 from blocking the exhaust port 101 after installation and affecting the exhaust, and also avoiding the L2 being too large and affecting the layout of the tab 11 on the pole group 10.

[0038] In this embodiment, when N≥2, the number of first electrodes 111 is 1 to N-1, and the number of second electrodes 112 is 1 to N-1, as long as the number of first electrodes 111 + the number of second electrodes 112 = N. Preferably, when N≥4, the number of first electrodes 111 ≥2 and the number of second electrodes 112 ≥2, wherein all first electrodes 111 are connected in parallel, and all second electrodes 112 are connected in parallel; for example, when N=4, the number of first electrodes 111 = 2 and the number of second electrodes 112 = 2, two first electrodes 111 are connected in parallel, and two second electrodes 112 are connected in parallel.

[0039] Preferably, N is an even number. Based on this, making the number of first tabs 111 the same as the number of second tabs 112 helps reduce the internal resistance of the electrode group 10.

[0040] In other alternative implementations, when N≥2, the number of first tabs 111 is different from the number of second tabs 112.

[0041] When N≥2, in a preferred embodiment, the first tab 111 and the second tab 112 are arranged alternately in sequence. That is, among the N ring-shaped tabs 11 arranged in a nested manner, the arrangement of the tabs 11 from the outermost to the innermost can be the first tab 111, the second tab 112, the first tab 111... or the second tab 112, the first tab 111, the second tab 112..., so that the second tab 112 is placed between two adjacent first tabs 111, and / or the first tab 111 is placed between two adjacent second tabs 112, so that the arrangement of the positive and negative tabs is regular, easy to identify, and helpful for the assembly of the battery cell, thus improving the assembly efficiency.

[0042] According to this utility model, an electrode assembly has an exhaust channel in the center; the electrode assembly has N tabs at its first axial end, where N=2 or N>2, some of the tabs are first tabs, and the remaining tabs are second tabs. This allows the first and second tabs to be led out from the same side of the electrode assembly, so that the battery cells do not need to flow through the large surface of the casing after assembly, which can effectively reduce the internal resistance of the battery, improve the internal space utilization of the battery cells, and increase the energy density of the battery cells, thus meeting the power consumption and range requirements of electronic products or electric devices; the distance between the wall of the exhaust channel and the outer wall of the electrode assembly in the radial direction of the battery cell is D, in mm; the width of the tabs in the radial direction of the battery cell is W, 4mm≤W≤0.5×D; the distance between adjacent first and second tabs in the radial direction of the battery cell is M, 1.5mm≤M≤10mm; this ensures that the tabs can be smoothly welded to the current collector, cover plate, or casing, and avoids interference between multiple tabs, thus ensuring the performance of the battery cells.

[0043] The battery cell provided by this utility model includes the electrode group as described above, and thus has all the above-mentioned beneficial effects, which will not be repeated here.

[0044] Finally, it should be noted that the above-described embodiments are merely specific implementations of this application, used to illustrate the technical solutions of this application, and not to limit them. The protection scope of this application is not limited thereto. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the technical scope disclosed in this application. Such modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be covered within the protection scope of this application. Therefore, the protection scope of this application should be determined by the protection scope of the claims.

Claims

1. An electrode assembly, characterized in that, The center of the electrode assembly is provided with an exhaust channel; the electrode assembly is provided with N electrode tabs at the first end in the axial direction, where N=2 or N>2, some of the electrode tabs are the first electrode tabs, and the remaining electrode tabs are the second electrode tabs, and the polarities of the first electrode tabs and the second electrode tabs are opposite. In the radial direction of the battery cell, the distance between the wall of the vent channel and the outer wall of the electrode assembly is D, in mm; in the radial direction of the battery cell, the width of the electrode tab is W, 4mm≤W≤0.5×D; In the radial direction of the cell, the distance between adjacent first and second tabs is M, where 1.5mm ≤ M ≤ 10mm.

2. The electrode assembly according to claim 1, characterized in that, The tab is formed as a ring structure coaxially arranged with the exhaust channel, where W is the distance between the inner ring wall and the outer ring wall of the tab in the radial direction of the cell; N tab rings are nested together.

3. The electrode assembly according to claim 2, characterized in that, In the radial direction of the cell, the distance between the outermost tab and the outer wall of the electrode group is L1, where 0mm≤L1≤5mm.

4. The electrode assembly according to claim 2 or 3, characterized in that, In the radial direction of the cell, the distance between the innermost tab and the wall of the exhaust channel is L2, where 0mm≤L2≤5mm.

5. The electrode assembly according to claim 1, characterized in that, N is an even number.

6. The electrode assembly according to claim 1 or 5, characterized in that, The number of the first electrode tabs is the same as the number of the second electrode tabs.

7. The electrode assembly according to claim 1, characterized in that, The number of the first electrode tabs is different from the number of the second electrode tabs.

8. The electrode assembly according to claim 2, characterized in that, When N≥2, the first electrode and the second electrode are arranged alternately in sequence, such that the second electrode is placed between two adjacent first electrodes, and / or the first electrode is placed between two adjacent second electrodes.

9. The electrode assembly according to claim 1, characterized in that, The pole group is formed into a cylindrical structure, and the circumferential sidewalls of the pole group and the second end of the pole group opposite to the first end in the axial direction are not provided with pole tabs.

10. A battery cell, characterized in that, Includes the pole group according to any one of claims 1 to 9.

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