Battery device and battery cell thereof

Abstract

This utility model discloses a battery cell, including a battery cell and an adapter plate. The battery cell includes at least a first sub-cell and a second sub-cell stacked together. The first sub-cell has a first tab bundle, and the second sub-cell has a second tab bundle. The first and second tab bundles are located at the same end of the battery cell. The first sub-cell is located on the side of the second sub-cell closer to the adapter plate. Both the first and second tab bundles include multiple layers of stacked tabs. The height of the second tab bundle is higher than that of the first tab bundle, and the height of the second tab bundle gradually increases from its position closer to the first tab bundle to its position further away from the first tab bundle. This battery cell avoids the problem of excessively long bent ends of the tab bundles on different sub-cells obstructing the welding area between the adapter plate and the terminal, ensuring the welding area between the adapter plate and the terminal, and improving the welding reliability of the adapter plate and the terminal. This utility model also discloses a battery device.

Description

Technical Field

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

[0002] A single battery cell includes a casing and a battery cell disposed inside the casing. The battery cell has multi-layered tabs, meaning each tab consists of multiple single-layer tabs. One end of each tab is connected to the battery cell, and the other end is welded to one end of an adapter plate, while the other end of the adapter plate is welded to a terminal post. Because of the radius (R) during winding, wound battery cells, if a single wound cell is too thick, are prone to lithium plating or high internal resistance. Therefore, it is necessary to combine at least two individual cells together. In the prior art, referring to... Figure 1 As shown, the battery cell includes a first sub-cell 01 and a second sub-cell 02. The first sub-cell 01 is provided with a first electrode bundle 03, and the second sub-cell 02 is provided with a second electrode bundle 04. Both the first electrode bundle 03 and the second electrode bundle 04 include multiple layers of electrode tabs, and the first electrode bundle 03 and the second electrode bundle 04 are at the same height. Since the adapter piece 05 is located on one side of the battery cell, when the multiple layers of electrode tabs are bent to one side and welded to the adapter piece 05, the distance between the electrode tabs of different layers and the adapter piece 05 is different, resulting in different end positions of the electrode tabs after bending. After bending, the ends of the electrode tabs will have layers of different lengths, i.e., a misaligned area. The misaligned area can easily block the area of ​​the adapter piece 05 used for welding with the terminal post, thereby affecting the welding of the adapter piece 05 and the terminal post, and reducing the reliability of the welding between the adapter piece 05 and the terminal post. Utility Model Content

[0003] In view of this, the present invention provides a battery cell that avoids the excessive length of the bent ends of the tab bundles on different cells from obstructing the area where the adapter plate and the terminal post are welded, thus ensuring the area of ​​the welding area between the adapter plate and the terminal post and improving the welding reliability between the adapter plate and the terminal post.

[0004] This utility model also provides a battery device.

[0005] To achieve the above objectives, this utility model provides the following technical solution:

[0006] A battery cell includes a battery cell and an adapter plate. The battery cell includes at least a first sub-cell and a second sub-cell stacked together. The first sub-cell has a first tab bundle, and the second sub-cell has a second tab bundle. The first and second tab bundles are located at the same end of the battery cell. The first sub-cell is located on the side of the second sub-cell closer to the adapter plate. Both the first and second tab bundles include multiple layers of stacked tabs. The height of the second tab bundle is higher than that of the first tab bundle. The height of the second tab bundle gradually increases from the position closer to the first tab bundle to the position farther away from the first tab bundle. Both the first and second tab bundles are electrically connected to the adapter plate.

[0007] As can be seen from the above technical solution, the battery cell provided by this utility model sets the tab bundles on different cells at different heights. The first tab bundle on the first cell closer to the adapter plate is lower in height, thus avoiding the first tab bundle from occupying the area on the adapter plate for welding with the terminal after bending. The second tab bundle on the second cell farther from the adapter plate is higher in height, thus solving the problem of its distance from the adapter plate after bending, ensuring the current carrying capacity, and making the end of the second tab bundle close to the end of the first tab bundle after bending. By setting the height of the second tab bundle to gradually increase from the position close to the first tab bundle to the position farther away, the end of the second tab bundle after bending is nearly flush, avoiding the end of the tab bundle after bending from blocking the area of ​​the adapter plate used for welding with the terminal, and not affecting the welding of the adapter plate and the terminal, the area of ​​the welding area between the adapter plate and the terminal is guaranteed, and the welding reliability between the adapter plate and the terminal is improved. The welding area is shown in the shaded area of ​​the grid in the figure.

[0008] This utility model also provides a battery device, including a plurality of battery cells arranged in a row, wherein the battery cells are those described above.

[0009] The battery device of this utility model includes the aforementioned battery cell, and therefore has the advantages of the aforementioned battery cell, which will not be repeated here. Attached Figure Description

[0010] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 This is a schematic diagram of the structure of a battery cell and electrode bundle in the prior art;

[0012] Figure 2A schematic diagram of the structure of the battery cell and electrode bundle at one angle according to an embodiment of the present invention;

[0013] Figure 3 for Figure 2 A schematic diagram of the battery cell and tab bundle from another angle provided in the embodiment;

[0014] Figure 4 for Figure 3 A partially enlarged structural diagram of part A in the diagram;

[0015] Figure 5 A schematic diagram of the structure of the electrode bundle and the adapter piece on the battery cell after welding at an angle according to an embodiment of this utility model;

[0016] Figure 6 A schematic diagram of the structure of the electrode bundle and the adapter piece on the battery cell after welding, provided in an embodiment of this utility model;

[0017] Figure 7 for Figure 6 A partially enlarged structural diagram of part B in the diagram;

[0018] Figure 8 A schematic diagram of the third angle of the electrode bundle and the adapter piece on the battery cell provided in this embodiment of the utility model;

[0019] Figure 9 A schematic diagram of the structure of the battery cell and the tab bundle at one angle, provided for another embodiment of the present invention;

[0020] Figure 10 for Figure 9 A schematic diagram of the battery cell and tab bundle from another angle provided in the embodiment;

[0021] Figure 11 for Figure 10 A partially enlarged structural diagram of part C in the diagram;

[0022] Figure 12 A schematic diagram of the structure of the battery cell and electrode bundle at one angle provided in the third embodiment of this utility model;

[0023] Figure 13 This is a structural schematic diagram of the battery cell and electrode bundle at one angle, provided in the fourth embodiment of this utility model.

[0024] in:

[0025] 01. First battery cell; 02. Second battery cell; 03. First electrode bundle; 04. Second electrode bundle; 05. Adapter plate.

[0026] 1. First battery cell,

[0027] 2. The second battery cell,

[0028] 3. First pole ear bundle,

[0029] 301. First pole piece,

[0030] 4. Second pole ear bundle,

[0031] 401. Second electrode ear piece; 402. First electrode ear bundle; 403. Second electrode ear bundle; 404. Third electrode ear bundle.

[0032] 5. Adapter plate. Detailed Implementation

[0033] This utility model discloses a battery cell that avoids the excessively long bent ends of the tab bundles on different cells from obstructing the area where the adapter plate and the terminal post are welded, thus ensuring the area of ​​the welding area between the adapter plate and the terminal post and improving the welding reliability of the adapter plate and the terminal post.

[0034] This utility model also discloses a battery device.

[0035] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0036] A single battery cell typically includes a battery casing, a battery cell, an adapter plate, and an electrolyte. The battery casing houses the battery cell and electrolyte, and generally includes a casing body and a cover plate. At least one positive electrode post and at least one negative electrode post are disposed on the casing and / or the cover plate. The battery cell includes one or more electrode assemblies, which are formed by stacking or winding positive electrode plates, negative electrode plates, and a separator. The separator is located between adjacent positive and negative electrode plates to insulate them. At least one end of the electrode assembly has a tab, and one end of the adapter plate is electrically connected to the tab, while the other end is electrically connected to the electrode post.

[0037] See Figures 2 to 13The battery cell of this utility model includes a battery cell and an adapter plate 5. The battery cell includes at least a first sub-cell 1 and a second sub-cell 2 stacked together. The first sub-cell 1 is provided with a first electrode bundle 3, and the second sub-cell 2 is provided with a second electrode bundle 4. The first electrode bundle 3 and the second electrode bundle 4 are located at the same end of the battery cell. The first sub-cell 1 is located on the side of the second sub-cell 2 close to the adapter plate 5. Both the first electrode bundle 3 and the second electrode bundle 4 include multiple layers of stacked electrode tabs. The height of the second electrode bundle 4 is higher than the height of the first electrode bundle 3. The height of the second electrode bundle 4 gradually increases from the position close to the first electrode bundle 3 to the position away from the first electrode bundle 3. The gradual increase in height here refers to the fact that the height of the tabs of the second electrode bundle 4 closest to the first electrode bundle 3 is lower than the height of the tabs farther away from the first electrode bundle 3. The heights of the tabs in the middle of the second electrode bundle 4 are the same, or the heights of the tabs in the middle of the second electrode bundle 4 change sequentially in layers or bundles: the heights are lower near the first electrode bundle 3 and higher far from the first electrode bundle 3. Both the first electrode bundle 3 and the second electrode bundle 4 are electrically connected to the adapter piece 5.

[0038] The first tab bundle 3 and the second tab bundle 4 are both composed of multiple stacked tabs. The height of the first tab bundle 3 and the second tab bundle 4 actually refers to the length of the tabs extending out of the battery cell. The height of the second tab bundle 4 is higher than the height of the first tab bundle 3, meaning that the height of the lowest tab in the second tab bundle 4 is also greater than the height of the tab in the first tab bundle 3.

[0039] This utility model's battery cell, by setting the tab bundles on different cells at different heights, features a lower height for the first tab bundle 3 on the first cell 1, closer to the adapter 5, thus preventing the first tab bundle 3 from occupying the area on the adapter 5 for welding to the terminal after bending. Conversely, a higher height for the second tab bundle 4 on the second cell 2, farther from the adapter 5, solves the problem of its greater distance from the adapter 5 after bending, ensuring current carrying capacity and ensuring that the end of the second tab bundle 4 is close to the bent end of the first tab bundle 3. The second tab bundle 4 is designed with a gradually increasing height from its position closer to the first tab bundle 3 to its position farther away, making the bent end of the second tab bundle 4 nearly flush. This prevents the bent end of the tab bundle from obstructing the area on the adapter 5 used for welding to the terminal, thus not affecting the welding of the adapter 5 and the terminal, ensuring the area of ​​the welding area between the adapter 5 and the terminal, and improving the welding reliability of the adapter 5 and the terminal. (See welding area...) Figure 5 The shaded area of ​​the grid.

[0040] In one specific embodiment, reference is made to Figures 2 to 4As shown, the first electrode bundle 3 includes several layers of first electrode tabs 301 stacked at the same height, and the second electrode bundle 4 includes several layers of second electrode tabs 401 stacked at different heights. The height of the second electrode tabs 401 increases sequentially from the position closest to the first electrode tabs 301 to the position furthest from the first electrode tabs 301, as shown. Figure 4 As shown, the ends of the multi-layered second electrode tabs 401 are connected to form a diagonal line. The further the second electrode tab 401 is from the first electrode tab 301, the longer it extends out of the second power distribution core 2, thus making the ends of the multi-layered second electrode tabs 401 more flush after bending. Figures 5 to 8 This is a schematic diagram of the structure where the first electrode ear bundle 3 and the second electrode ear bundle 4 are bent and welded to the adapter piece 5.

[0041] Furthermore, to ensure the flatness of the bent ends of the multi-layered second electrode lugs 401, the height difference between adjacent second electrode lugs 401 needs to be limited. Specifically, the height difference between adjacent second electrode lugs 401 is H1. The specific value of the height difference H1 is calculated by those skilled in the art based on the thickness of the second electrode lugs 401 and the distance between two adjacent second electrode lugs 401. This calculation method is commonly used in the art and will not be elaborated here. The height difference between the second electrode lug 401 closest to the first electrode lug 301 and the first electrode lug 301 is also H1, ensuring that the end of the second electrode lug 401 closest to the first electrode lug 301 is flush with the bent end of the first electrode lug 301 after bending. H1 ranges from 0.1mm to 2.1mm, specifically any value among 0.1mm, 0.8mm, and 2.1mm, or a value between any two values. If H1 is too small or too small, it will be difficult to meet the requirement of flush ends after bending.

[0042] In another specific embodiment, refer to Figures 9 to 11 The first electrode bundle 3 includes several layers of first electrode tabs 301 of the same height. The second electrode bundle 4 includes at least a first electrode bundle 402 and a second electrode bundle 403 of different heights. The first electrode bundle 402 and the second electrode bundle 403 are stacked, and both the first electrode bundle 402 and the second electrode bundle 403 include several layers of second electrode tabs 401. Specifically, the first electrode bundle 402 is located in the second electrode bundle 4 near the first electrode bundle 3, and the second electrode bundle 403 is located in the second electrode bundle 4 away from the first electrode bundle 3. Figure 9As shown, the second electrode bundle 4 includes a first electrode bundle 402 and a second electrode bundle 403 arranged in parallel. Since the second electrode bundle 403 is farther from the adapter piece 5 than the first electrode bundle 402, the height of the second electrode bundle 403 is greater than the height of the first electrode bundle 402 to avoid misalignment at the end of the second electrode bundle 4 after bending. At the same time, in order to improve the misalignment between the end of the first electrode bundle 402 after bending and the end of the first electrode bundle 3, the height of the first electrode bundle 402 is greater than the height of the first electrode bundle 3.

[0043] Furthermore, the height difference between the second polarity ear bundle 403 and the first polarity ear bundle 402 is H2, and the height difference between the first polarity ear bundle 402 and the first polarity ear bundle 3 is also H2, as shown below. Figure 11 As shown. H2 ranges from 2.5mm to 11mm, specifically any value from 2.5mm, 5mm, 8mm, 11mm, or any two values ​​in between. By limiting the height difference H2, the neatness of the bent rear end of the second pole ear bundle 4 is ensured to be within acceptable limits, while also guaranteeing the flow area, thus ensuring good flow.

[0044] In this design, the first electrode bundle 402 has n1 layers, and the second electrode bundle 403 has n2 layers. n1 is not less than n2, meaning n1 and n2 are the same, or n1 is greater than n2. The ratio of n1 / n2 ranges from 1 to 3, specifically any value from 1, 1.8, 3, or any value between two of these. Controlling n1 / n2 within this range ensures sufficient flow area and mitigates the misalignment at the end of the second electrode bundle 4. If n1 / n2 is too large, meaning the first electrode bundle 402 (which has a low height) has too many layers, the welding area between it and the adapter piece 5 will be small due to the short length of the first electrode bundle 402, resulting in poor current flow capacity. If n1 / n2 is too small, although the current flow capacity is good, the excessive number of layers in the second electrode bundle 403 will make the misalignment at the end of this electrode bundle more pronounced after bending.

[0045] In the third embodiment, based on the above embodiments, the second electrode ear bundle 4 further includes a third branch ear bundle 404, that is, the second electrode ear bundle 4 includes a first branch ear bundle 402, a second branch ear bundle 403, and a third branch ear bundle 404, as shown below. Figure 12As shown. The third electrode bundle 404 includes several layers of second electrode tabs 401. The third electrode bundle 404 is located on the side of the second electrode bundle 403 away from the first electrode bundle 402, and the height of the third electrode bundle 404 is greater than the height of the second electrode bundle 403. The first electrode bundle 402 has n1 layers, the second electrode bundle 403 has n2 layers, and the third electrode bundle 404 has n3 layers; specifically, n1 ≥ n2 ≥ n3. The specific values ​​of n1, n2, and n3 are set by those skilled in the art according to actual needs.

[0046] Specifically, the height difference between the second electrode bundle 403 and the first electrode bundle 402 is H3, the height difference between the first electrode bundle 402 and the first electrode bundle 3 is H3, and the height difference between the third electrode bundle 404 and the second electrode bundle 403 is H3, thus ensuring that the bent end of the second electrode bundle 4 is nearly flush. H3 ranges from 1.8mm to 7.5mm, specifically any value from 1.8mm, 3mm, 5mm, 7.5mm, or any two values. By limiting the height difference H3, the neatness of the bent end of the second electrode bundle 4 is ensured to be within acceptable limits, while also guaranteeing current carrying capacity, thus ensuring good current carrying capacity of the electrode bundle.

[0047] In the fourth embodiment, the first electrode bundle 3 includes several layers of first electrode tabs 301 with gradually increasing height, such as... Figure 13 As shown, the height of the first electrode tab 301 near the second electrode bundle 4 is higher than the height of the first electrode tab 301 away from the second electrode bundle 4. In this embodiment, the second electrode bundle 4 includes several layers of second electrode tabs 401 with different heights, and the height of the second electrode tabs 401 near the first electrode bundle 3 is lower than the height of the second electrode tabs 401 away from the first electrode bundle 3. In other embodiments, the second electrode bundle 4 may also include several sub-electrode bundles with different heights, and the height of the several sub-electrode bundles gradually increases from the side near the first electrode bundle 3 to the side away from it.

[0048] In one embodiment, the number of layers of the first ear bundle 3 is the same as the number of layers of the second ear bundle 4. In other embodiments, the number of layers of the first ear bundle 3 and the second ear bundle 4 may also be different, which is not limited here.

[0049] The first electrode bundle 3 and the second electrode bundle 4 have the same width, and the width direction of the electrode bundle is set perpendicular to its height direction.

[0050] The battery cell of this utility model sets the tab bundles on the cell at different distances from the adapter piece 5 to different heights, so that the ends of the tab bundles on different cells are basically flush after bending. While meeting the current flow area requirement, it avoids severe misalignment at the ends of the tab bundles, thereby avoiding the obstruction of the welding area of ​​the terminal post caused by misalignment and improving the welding reliability of the adapter piece 5 and the terminal post.

[0051] This utility model also provides a battery device, including a plurality of battery cells arranged in a row, wherein the battery cells are those described above.

[0052] In the description of this solution, it should be understood that 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 technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this solution, "multiple" means two or more, unless otherwise explicitly specified.

[0053] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0054] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A battery cell comprising a cell core and a tab, characterized in that, The battery cell includes at least a first branch cell and a second branch cell stacked together. The first branch cell is provided with a first electrode bundle, and the second branch cell is provided with a second electrode bundle. The first electrode bundle and the second electrode bundle are located at the same end of the battery cell. The first branch cell is disposed on the side of the second branch cell close to the adapter plate. Both the first electrode bundle and the second electrode bundle include multiple layers of stacked electrode tabs. The height of the second electrode bundle is higher than the height of the first electrode bundle. The height of the second electrode bundle gradually increases from the position close to the first electrode bundle to the position away from the first electrode bundle. Both the first electrode bundle and the second electrode bundle are electrically connected to the adapter plate.

2. The battery cell of claim 1, wherein, The first electrode bundle includes several layers of first electrode tabs stacked at the same height, and the second electrode bundle includes several layers of second electrode tabs stacked at different heights. The height of the second electrode tabs increases sequentially from the position closest to the first electrode tab to the position furthest from the first electrode tab.

3. The battery cell of claim 2, wherein, The height difference between adjacent second electrode tabs is H1, and the height difference between the second electrode tab closest to the first electrode tab and the first electrode tab is also H1; The range of H1 is 0.1mm-2.1mm.

4. The battery cell of claim 1, wherein, The first electrode bundle includes several layers of first electrode tabs of the same height. The second electrode bundle includes at least a first electrode bundle and a second electrode bundle of different heights. The first electrode bundle and the second electrode bundle are stacked. The first electrode bundle is located near the first electrode bundle of the second electrode bundle. The second electrode bundle is located away from the first electrode bundle of the second electrode bundle. The height of the second electrode bundle is greater than the height of the first electrode bundle.

5. The battery cell of claim 4, wherein, The height difference between the second polarizer bundle and the first polarizer bundle is H2, and the height difference between the first polarizer bundle and the first polarizer bundle is also H2, with H2 ranging from 2.5mm to 11mm.

6. The battery cell of claim 4, wherein, The first polarizer ear bundle has n1 layers, the second polarizer ear bundle has n2 layers, n1 is not less than n2, and the range of n1 / n2 is 1-3.

7. The battery cell of claim 4, wherein, The second electrode bundle also includes a third branch electrode bundle, which is located on the side of the second branch electrode bundle away from the first branch electrode bundle, and the height of the third branch electrode bundle is greater than the height of the second branch electrode bundle.

8. The battery cell of claim 7, wherein, The first polarizer bundle has n1 layers, the second polarizer bundle has n2 layers, and the third polarizer bundle has n3 layers, where n1 ≥ n2 ≥ n3.

9. The battery cell of claim 7, wherein, The height difference between the second polarity ear bundle and the first polarity ear bundle is H3, the height difference between the first polarity ear bundle and the first polarity ear bundle is H3, and the height difference between the third polarity ear bundle and the second polarity ear bundle is H3, with H3 ranging from 1.8mm to 7.5mm.

10. The battery cell of claim 1, wherein, The number of layers in the first ear bundle is the same as the number of layers in the second ear bundle.

11. The battery cell of claim 1, wherein, The first electrode bundle includes several layers of first electrode tabs with gradually increasing height, and the height of the first electrode tabs closer to the second electrode bundle is higher than the height of the first electrode tabs farther away from the second electrode bundle.

12. The battery cell of claim 11, wherein, The second electrode bundle includes several layers of second electrode tabs of different heights, with the height of the second electrode tabs closer to the first electrode bundle being lower than the height of the second electrode tabs farther away from the first electrode bundle.

13. A battery device comprising a plurality of battery cells arranged in series, characterized in that, The battery cell is the battery cell described in any one of claims 1-12.

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