Battery monomer, battery pack and electric device
By incorporating extended tabs within the battery cell to connect electrically with the external circuitry, the problems of low energy density caused by the space occupied by the tab leads and bending operations are solved, thereby improving the energy density of the battery cell.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HUIZHOU LIWINON NEW ENERGY TECH CO LTD
- Filing Date
- 2025-06-23
- Publication Date
- 2026-07-10
AI Technical Summary
The low energy density of a single battery cell is mainly due to the space occupied by the tab leads and the redundant space caused by bending operations.
An extended tab is provided inside the battery cell. Both the extended tab and the original tab are connected to the electrode plate. The distance of the extended tab extending from the electrode plate is greater than that of the original tab. It is designed to be electrically connected to the external circuit, avoiding the need for additional connection of the tab lead-out component and reducing the need for tab bending operations.
By extending the tab design, the thickness of the tab lead-out component is reduced, the volume of the electrode sheet is increased, the energy density of the battery cell is further increased, and the redundant space caused by tab bending is reduced.
Smart Images
Figure CN224481166U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of battery technology, and in particular to a battery cell, battery pack and power supply device. Background Technology
[0002] With the development of new energy sources, more and more fields are adopting new energy as a power source. Due to its advantages such as high energy density, rechargeability, safety, and environmental friendliness, battery devices are widely used in new energy vehicles, consumer electronics, energy storage systems, and other fields. Battery cells typically have tabs connected to leads welded together. After welding, the tabs are bent at the head of the cell, causing them to occupy part of the cell's internal space, resulting in a lower energy density for the battery cell. Utility Model Content
[0003] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a battery cell, a battery pack, and an electrical device that can solve the problem of low energy density in battery cells.
[0004] The battery cell according to the first aspect of this application includes:
[0005] An electrode assembly includes interconnected electrode plates and tabs. There are two electrode assemblies, one of which is a positive electrode assembly with interconnected tabs, and the other is a negative electrode assembly with interconnected tabs.
[0006] Extended tabs, both the positive electrode assembly and the negative electrode assembly are connected to the extended tabs;
[0007] In this configuration, at least one of the electrode plates corresponding to the positive electrode assembly is connected to a tab and an extension tab, and at least one of the electrode plates corresponding to the negative electrode assembly is connected to a tab and an extension tab. The extension tab is electrically connected to the tab corresponding to the corresponding electrode assembly, and the extension tab extends beyond the electrode plate by a greater distance than the tab extends beyond the electrode plate. The extension tab is used for electrical connection to an external circuit.
[0008] The battery cell according to the embodiments of this application has at least the following beneficial effects:
[0009] In the embodiments of this application, the battery cell is provided with an extended tab connected to the electrode assembly. Both the extended tab and the tab are connected to the corresponding electrode sheet, and the length of the extended tab extending beyond the electrode sheet is greater than the length of the tab extending beyond the electrode sheet. By enabling electrical conduction with the outside through the extended tab, it is possible to avoid connecting additional tab leads within the battery cell, thereby saving the thickness of the tab leads. Since both the extended tab and the tab are connected to the electrode sheet, the extended tab does not increase the thickness of the electrode assembly, and the volume of the electrode sheet within the electrode assembly can be increased, thereby increasing the energy density of the battery cell. Furthermore, since the tabs of the electrode assembly need to be bent twice before welding, enabling electrical conduction with the outside through the extended tab eliminates the need for bending the tab, thereby further shortening the size of the tab in the arrangement direction between the electrode sheet and the tab, and further increasing the size of the electrode sheet, thereby increasing the energy density of the battery cell.
[0010] According to some embodiments of this application, the thickness of the extended tab is greater than or equal to the thickness of the tab.
[0011] According to some embodiments of this application, the ratio between the thickness of the extended tab and the thickness of the tab is greater than or equal to 1 and less than or equal to 5.
[0012] According to some embodiments of this application, the electrode assembly further includes a diaphragm attached to the electrode sheet, the sum of the thicknesses of all the tabs is a first distance D1, the distance by which the tabs extend beyond the diaphragm is a second distance D2, and the first distance D1 and the second distance D2 satisfy D1≤D2≤2D1.
[0013] According to some embodiments of this application, the electrode assembly further includes a diaphragm attached to the electrode sheet, the sum of the thicknesses of all the tabs is a first distance D1, the distance by which the extended tab extends beyond the diaphragm is a third distance D3, the thickness of the extended tab is a fourth distance D4, and the first distance D1, the third distance D3 and the fourth distance D4 satisfy D1+D4≤D3≤2*(D1+D4).
[0014] According to some embodiments of this application, the width of the electrode tab ranges from 2mm to 10mm.
[0015] According to some embodiments of this application, the distance between the projected area of the electrode and the projected area of the extended electrode along the thickness direction of the battery cell and along the width direction of the electrode tab ranges from 2mm to 10mm.
[0016] According to some embodiments of this application, the battery cell is a stacked cell.
[0017] A second aspect of this application provides a battery pack, comprising:
[0018] Box;
[0019] The battery cell of any of the above, wherein the battery cell is located inside the casing.
[0020] A third aspect of this application provides an electrical device, comprising:
[0021] Main body of the device;
[0022] The battery pack of any of the above is used to power the main body of the device.
[0023] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description
[0024] The present application will be further described below with reference to the accompanying drawings and embodiments, wherein:
[0025] Figure 1 This is a side view of the structure of a single battery cell in one embodiment of this application;
[0026] Figure 2 This is a top view of the structure of a single battery cell in one embodiment of this application;
[0027] Figure 3 This is a schematic diagram of the assembly of the electrode plate, electrode tab, and extended electrode tab in one embodiment of this application;
[0028] Figure 4 This is a structural side view of a battery cell in one embodiment of this application.
[0029] Figure label:
[0030] 100, Electrode assembly; 110, Electrode sheet; 120, Electrode tab; 130, Diaphragm; 200, Extended electrode tab; 210, First electrode tab; 220, Second electrode tab; 300, Housing. Detailed Implementation
[0031] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.
[0032] In the description of this application, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., indicating the orientation or position relationship, are based on the orientation or position relationship 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, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.
[0033] In the description of this application, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.
[0034] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.
[0035] In the description of this application, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0036] Currently, judging from market trends, the application of battery devices is becoming increasingly widespread. Battery devices are not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power plants, but also widely applied in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in aerospace and other fields. With the continuous expansion of the application areas of battery devices, the market demand is also constantly increasing.
[0037] In related technologies, multiple layers of foil tabs and tab leads need to be welded together inside the battery cell for conductivity. The tab leads occupy a portion of the battery cell's thickness. Furthermore, to accommodate the aluminum-plastic film encapsulation space and for welding with the tab leads, the tabs must undergo two bends (the first bend makes the tab parallel to the main plane of the casing, and the second bend makes it fit against the sidewall of the casing). These two bending operations create redundant space in the tab area, resulting in smaller electrode sizes and lower energy density in the battery cell. Typically, the tab extension length of a battery cell is 3mm~5mm, and after the tab bending, along the tab-electrode alignment direction, the tab size is 2.0mm~2.5mm.
[0038] In this embodiment, an extended tab 200 with a relatively long extension length is provided within the battery cell, thereby eliminating the need for the tab 120 lead-out component. The battery cell can compress the space occupied by the tab 120, and the volume of the electrode 110 can be increased accordingly, thereby improving the energy density of the battery cell.
[0039] This application provides an electrical device, which includes a device body and a battery pack, the battery pack being used to supply power to the device body.
[0040] Electrical devices can be, for example, mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships, and spacecraft.
[0041] The technical solutions described in this application are not limited to the devices described above, but can also be applied to all devices that use battery devices.
[0042] The battery apparatus mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells connected in series, parallel, or mixed connections via a busbar.
[0043] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells.
[0044] As an example, a battery cell assembly can be a battery module, which is formed by arranging and fixing multiple battery cells together to form an independent module. As another example, a battery module can be formed by bundling multiple battery cells together with cable ties.
[0045] In some embodiments, the battery device may be a battery pack, which includes a housing and one or more individual battery cells housed within the housing.
[0046] This application also provides a battery pack, which includes a housing and at least one battery cell, with the battery cell located inside the housing.
[0047] In some embodiments of this application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.
[0048] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.
[0049] This application provides a single battery cell; please refer to [link / reference]. Figure 1 and Figure 2 The battery cell includes an electrode assembly 100 and extended tabs 200. The electrode assembly 100 includes interconnected electrode plates 110 and tabs 120. There are two electrode assemblies 100: one is a positive electrode assembly 100 with interconnected tabs 120, and the other is a negative electrode assembly 100 with interconnected tabs 120. Both the positive and negative electrode assemblies 100 are connected to extended tabs 200. In this configuration, at least one electrode 110 of the positive electrode assembly 100 is connected to a tab 120 and an extension tab 200. Similarly, at least one electrode 110 of the negative electrode assembly 100 is connected to a tab 120 and an extension tab 200. The extension tab 200 is electrically connected to the tab 120 of its corresponding electrode assembly 100. The extension tab 200 extends beyond the electrode 110 by a greater distance than the tab 120 extends beyond the electrode 110. The extension tab 200 is used for electrical connection to an external circuit. For example, the extension tab 200 connected to the positive electrode assembly 100 is a first tab 210. The first tab 210 is connected to the corresponding electrode 110, and the first tab 210 extends beyond the electrode 110 by a greater distance than the tab 120 extends beyond the electrode 110. The extended tab 200 connected to the negative electrode assembly 100 is a second tab 220. The second tab 220 is connected to the corresponding electrode 110, and the distance by which the second tab 220 extends out of the electrode 110 is greater than the distance by which the tab 120 extends out of the electrode 110. For example, the tabs 120 of the positive electrode assembly 100 are connected to each other by adhesive bonding, and the tabs 120 of the negative electrode assembly are connected to each other by adhesive bonding.
[0050] The distance by which the extended tab 200 extends beyond the electrode 110 refers to the length of the area in which the projected area of the extended tab 200 does not overlap with the projected area within the electrode 110, projected along the thickness direction of the battery cell and along the arrangement direction of the extended tab 200 and the electrode 110.
[0051] For example, the length direction of the extended tab 200 is as follows Figure 1 The direction indicated by the middle arrow R1.
[0052] For example, the extension tab 200 and the tab 120 are located on the same side of the corresponding electrode 110.
[0053] In the embodiment of this application, the battery cell is provided with an extended tab 200 connected to the electrode assembly 100. Both the extended tab 200 and the tab 120 are connected to the corresponding electrode sheet 110. The length of the extended tab 200 extending out of the electrode sheet 110 is greater than the length of the tab 120 extending out of the electrode sheet 110. By enabling electrical conduction with the outside through the extended tab 200, it is possible to avoid connecting an additional tab 120 lead-out component inside the battery cell, thereby saving the thickness of the tab 120 lead-out component. Since both the extended tab 200 and the tab 120 are connected to the electrode sheet 110, the extended tab 200 does not additionally increase the thickness of the electrode assembly 100, and the volume of the electrode sheet 110 inside the electrode assembly 100 can be increased, thereby increasing the energy density of the battery cell. Furthermore, since the tab 120 of the electrode assembly 100 needs to be bent twice before welding, extending the tab 200 to conduct electricity with the outside can eliminate the need to bend the tab 120. This can further shorten the size of the tab 120 in the arrangement direction of the electrode sheet 110 and the tab 120, and the size of the electrode sheet 110 can be further increased, thereby increasing the energy density of the battery cell.
[0054] In one embodiment, the battery cell further includes a housing 300, an electrode assembly 100 located inside the housing 300, and an extended tab 200 partially bonded to the housing 300.
[0055] In one embodiment, the thickness of the extended tab 200 is greater than or equal to the thickness of the tab 120. The thickness directions of the extended tab 200, the tab 120, and the battery cell are all arranged parallel to each other, with the thickness direction of the battery cell perpendicular to its large surface area. The large surface area of the battery cell is a surface with a much larger surface area than other surfaces, and the battery cell has two opposing large surfaces. During the assembly of the battery cell, the extended tab 200 needs to be encapsulated with an external aluminum-plastic film. A larger thickness of the extended tab 200 increases its strength, thereby reducing the likelihood of breakage during assembly and ultimately increasing the yield rate of the battery cell.
[0056] For example, the thickness direction of a single battery cell is as follows: Figure 1 The direction indicated by the middle arrow R2.
[0057] It is understood that other embodiments of this application do not limit the thickness of the extended tab 200 to be greater than the thickness of the tab 120. Exemplarily, the thickness of the extended tab 200 is less than the thickness of the tab 120.
[0058] In one embodiment, the ratio between the thickness of the extended tab 200 and the thickness of the tab 120 is greater than or equal to 1 and less than or equal to 5.
[0059] For example, the ratio between the thickness of the extension tab 200 and the thickness of the tab 120 is 1.0, 1.1, 2.0, 3.0, 4.0 or 5.0.
[0060] For example, the thickness of the tab 120 ranges from 4 μm to 20 μm.
[0061] In the embodiments of this application, the thickness of the extended tab 200 and the thickness of the tab 120 are within a suitable range, which can make the extended tab 200 have high strength, and also reduce the size occupied by the extended tab 200 in the thickness direction of the battery cell, thereby increasing the number of layers of the electrode 110 and reducing the energy density loss of the battery cell.
[0062] It is understood that other embodiments of this application do not limit the ratio between the thickness of the extended tab 200 and the thickness of the tab 120.
[0063] In one embodiment, please refer to Figure 4 The electrode assembly 100 also includes a diaphragm 130 attached to the electrode 110. The sum of the thicknesses of all the tabs 120 is a first distance D1, and the distance by which the tabs 120 extend beyond the diaphragm 130 is a second distance D2. The first distance D1 and the second distance D2 satisfy D1≤D2≤2D1. The diaphragm 130 is made of insulating material and is used to suppress short circuits between adjacent electrode assemblies. The appropriate distance by which the tabs 120 extend beyond the electrode 110 allows sufficient connection space for the tabs 120 to connect with each other, resulting in a high connection strength between the tabs 120. It also reduces the space occupied by the tabs 120 in the direction extending beyond the electrode 110, thereby reducing the impact of the tabs 120 on energy density. For example, the tabs 120 extend beyond the electrode 110 along their length direction, and the length direction of the tabs 120 is parallel to the length direction of the extended tabs 200.
[0064] Understandably, the sum of the thicknesses of all tabs 120 and the distance by which tabs 120 extend beyond the electrode plate 110 can be obtained by measuring with vernier calipers under normal temperature and pressure conditions before the first charge of the battery cell.
[0065] It is understood that other embodiments of this application do not limit the relationship between the first distance and the second distance.
[0066] In one embodiment, please refer to Figure 4The electrode assembly 100 also includes a separator 130 attached to the electrode 110. The sum of the thicknesses of all the tabs 120 is a first distance D1, the distance by which the extended tab 200 extends beyond the separator 130 is a third distance D3, and the thickness of the extended tab 200 is a fourth distance D4. The first distance D1, the third distance D3, and the fourth distance D4 satisfy D1+D4≤D3≤2*(D1+D4). The appropriate range of the distance the extended tab 200 extends beyond the electrode 110 ensures sufficient connection space on the extended tab 200 to encapsulate it with the aluminum-plastic film, resulting in a high connection strength between the extended tab 200 and the aluminum-plastic film. This also helps control the manufacturing cost of the battery cell to some extent.
[0067] Understandably, the distance by which the extension tab 200 extends beyond the electrode 110 can be measured by vernier calipers under normal temperature and pressure conditions before the first charge of the battery cell.
[0068] It is understood that other embodiments of this application do not limit the distance by which the extension tab 200 extends beyond the electrode 110.
[0069] In one embodiment, projected along the thickness direction of the battery cell, the width of the tab 120 ranges from 2mm to 10mm. It is understood that the width of the tab 120 affects the current-carrying capacity of the battery cell to some extent. Furthermore, during charging and discharging, the tab 120 generates heat due to its resistance, and its width affects the distribution of this heat. A suitable width for the tab 120 allows for high current-carrying capacity while also reducing the manufacturing cost of the battery cell to some extent. Moreover, since the width of the electrode 110 is limited, a suitable width for the tab 120 facilitates its arrangement in the width direction.
[0070] For example, the width of tab 120 is 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 10 mm. It is understood that the width of tab 120 can be measured with a ruler under normal temperature and pressure conditions before the first charge of the battery cell.
[0071] For example, the width of the tab 120 is as follows Figure 3 As shown in the medium dimension D5.
[0072] For example, the width direction of the tab 120 is as follows: Figure 2 The direction indicated by the middle arrow R3.
[0073] It is understood that other embodiments of this application do not limit the width of the tab 120.
[0074] In one embodiment, please refer to Figure 3 The distance between the projection area of tab 120 and the projection area of extended tab 200 along the thickness direction of the battery cell and along the width direction of tab 120 is 2mm to 10mm.
[0075] It should be noted that, along the width direction of the tab 120, the distance between the projection area of the tab 120 and the projection area of the extended tab 200 refers to the distance between the outline of the projection area of the tab 120 toward the projection area of the extended tab 200 and the outline of the projection area of the extended tab 200 toward the projection area of the tab 120.
[0076] For example, the distance between the projection area of tab 120 and the projection area of extension tab 200 is 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 10 mm. It is understood that the distance between tab 120 and extension tab 200 along the width direction of tab 120 can be obtained by measuring with a ruler under normal temperature and pressure.
[0077] For example, along the width direction of the tab 120, the distance between the projection area of the tab 120 and the projection area of the extended tab 200 is as follows: Figure 3 As shown in the medium dimension D6.
[0078] In the embodiment of this application, the distance between the electrode 120 and the extended electrode 200 is within a suitable range along the width direction of the electrode 120. This not only reduces the interference between the electrode 120 and the extended electrode 200 during the processing, but also allows the arrangement of the electrode 120 and the extended electrode 200 to better adapt to the width of the electrode 110.
[0079] In one embodiment, the battery cell is a stacked cell. When the battery cell is a stacked cell, the positive electrode assembly 100 of the battery cell includes multiple positive electrode plates 110 and multiple tabs 120, each positive electrode plate 110 is connected to a corresponding tab 120, and one of the positive electrode plates 110 in the positive electrode assembly 100 is also connected to a first tab 210. The negative electrode assembly 100 of the battery cell includes multiple negative electrode plates 110 and multiple tabs 120, each negative electrode plate 110 is connected to a corresponding tab 120, and one of the negative electrode plates 110 in the negative electrode assembly 100 is also connected to a second tab 220.
[0080] It is understood that other embodiments of this application do not limit the type of battery cell to a stacked cell. Exemplarily, the type of battery cell is a square wound cell.
[0081] The above embodiments are merely illustrative of the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and all should be covered within the scope of the specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of protection.
Claims
1. A battery cell, characterized in that, include: An electrode assembly includes interconnected electrode plates and tabs. There are two electrode assemblies, one of which is a positive electrode assembly with interconnected tabs, and the other is a negative electrode assembly with interconnected tabs. Extended tabs, both the positive electrode assembly and the negative electrode assembly are connected to the extended tabs; In this configuration, at least one of the electrode plates corresponding to the positive electrode assembly is connected to a tab and an extension tab, and at least one of the electrode plates corresponding to the negative electrode assembly is connected to a tab and an extension tab. The extension tab is electrically connected to the tab corresponding to the corresponding electrode assembly, and the extension tab extends beyond the electrode plate by a greater distance than the tab extends beyond the electrode plate. The extension tab is used for electrical connection to an external circuit.
2. The battery cell according to claim 1, characterized in that, The thickness of the extended tab is greater than or equal to the thickness of the tab itself.
3. The battery cell according to claim 2, characterized in that, The ratio between the thickness of the extended tab and the thickness of the tab is greater than or equal to 1 and less than or equal to 5.
4. The battery cell according to any one of claims 1 to 3, characterized in that, The electrode assembly also includes a diaphragm attached to the electrode sheet. The sum of the thicknesses of all the tabs is a first distance D1, and the distance by which the tabs extend beyond the diaphragm is a second distance D2. The first distance D1 and the second distance D2 satisfy D1≤D2≤2D1.
5. The battery cell according to any one of claims 1 to 3, characterized in that, The electrode assembly further includes a diaphragm attached to the electrode sheet. The sum of the thicknesses of all the tabs is a first distance D1. The distance by which the extended tab extends beyond the diaphragm is a third distance D3. The thickness of the extended tab is a fourth distance D4. The first distance D1, the third distance D3, and the fourth distance D4 satisfy D1+D4≤D3≤2*(D1+D4).
6. The battery cell according to any one of claims 1 to 3, characterized in that, The width of the electrode tab ranges from 2mm to 10mm.
7. The battery cell according to any one of claims 1 to 3, characterized in that, Projecting along the thickness direction of the battery cell, the distance between the projected area of the electrode and the projected area of the extended electrode along the width direction ranges from 2mm to 10mm.
8. The battery cell according to any one of claims 1 to 3, characterized in that, The battery cell is a stacked cell.
9. A battery pack, characterized in that, include: Box; At least one battery cell as described in any one of claims 1 to 8, wherein the battery cell is located within the housing.
10. An electrical device, characterized in that, include: Main body of the device; The battery pack of claim 9 is used to power the main body of the device.