Battery cell and battery
By adopting the design of the first and second tab groups in the battery, the problems of uneven current distribution and poor packaging are solved, faster charging and lower temperature rise are achieved, and the packaging effect is improved.
Patent Information
- Application Number
- CN202511070056.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-31
- Publication Date
- 2025-09-09
AI Technical Summary
The uneven current distribution in existing batteries leads to long charging time and large charging temperature rise, and the increased length of the electrode sheets leads to poor packaging.
The design of the first tab group and the second tab group is adopted. The tab groups are arranged at intervals along the thickness direction of the core, and steps are formed at the edges of the tab groups to improve the uniformity of current distribution and reduce the risk of poor packaging through the steps.
The uniformity of current distribution is improved, charging time and charging temperature rise are reduced, and the packaging effect of the shell and the tab group is improved to avoid poor packaging.
Smart Images
Figure CN120613562A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of battery technology, and in particular to a battery cell and a battery. Background Art
[0002] With the development of electronic products, the capacity of batteries in these products has continued to increase. One key way to achieve this increase in battery capacity is to increase the length of the electrode tabs. However, this increase in length also leads to thicker battery cells, which in turn impairs heat dissipation. Existing battery cells typically consist of a positive and a negative tab. As the length of the electrode tabs increases, this can lead to uneven current distribution in the battery, resulting in longer charging times and higher temperature rises. Summary of the Invention
[0003] The embodiments of the present application provide a battery cell and a battery that can solve the problems in the related art of long charging time and large charging temperature rise caused by uneven current distribution in the battery.
[0004] In a first aspect, a battery cell is provided, comprising:
[0005] A housing, wherein a housing is provided with a housing cavity, and a first end of the housing is provided with a first opening and a second opening communicating with the housing cavity;
[0006] a winding core, the winding core being disposed in the accommodating cavity;
[0007] a first tab group, the first tab group including a first tab and a second tab of the same polarity, the first tab and the second tab being arranged at intervals along the thickness direction of the winding core, one end of the first tab group being electrically connected to the winding core, the other end of the first tab group extending out of the shell through the first opening, the first tab group forming a first step along the thickness direction of the winding core, the first step being located at an edge region of the first tab group, the shell being sealedly connected to the first tab group, and the region where the first tab group is sealedly connected to the shell including the region where the first step is located;
[0008] A second electrode tab group, wherein the second electrode tab group includes at least one of a third electrode tab and a fourth electrode tab with the same polarity, wherein one of the first electrode tab and the third electrode tab is a positive electrode tab and the other is a negative electrode tab; one end of the second electrode tab group is electrically connected to the winding core, and the other end of the second electrode tab group extends out of the shell through the second opening.
[0009] In a second aspect, a battery is provided, comprising the battery cell described in the first aspect.
[0010] In the embodiment of the present application, by making the battery cell include a first tab group and a second tab group, since the battery cell can be charged and discharged simultaneously through the first tab group and the second tab group, it is beneficial to improve the uniformity of the current distribution in the battery cell, thereby reducing the charging time during the charging process of the battery cell, and reducing the temperature rise during the charging process. In addition, since the first tab and the second tab in the first tab group are stacked in the thickness direction of the winding core, the thickness of the first tab group is relatively large. During the packaging process of the shell and the first tab group, the edge of the first tab group is prone to poor packaging. Based on this, in the embodiment of the present application, by making the first tab group form a first step position along the thickness direction of the winding core, and the first step position is located at the edge area of the first tab group, the thickness at the edge of the first tab group can be reduced, thereby improving the packaging effect of the shell and the first tab group. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Figure 1 This is one of the structural schematic diagrams of a battery cell provided in this application;
[0012] Figure 2 yes Figure 1 Schematic diagram of the structure of the winding core inside the battery cell;
[0013] Figure 3 yes Figure 1 A top view at point A in FIG;
[0014] Figure 4 yes Figure 1 Side view of;
[0015] Figure 5 This is the second structural diagram of a battery cell provided by this application;
[0016] Figure 6 yes Figure 5 Schematic diagram of the structure of the winding core inside the battery cell;
[0017] Figure 7 yes Figure 5 A top view of point B in FIG.
[0018] Figure 8 yes Figure 5 Side view of;
[0019] Figure 9 This is the third structural diagram of a battery cell provided by this application;
[0020] Figure 10 yes Figure 9 Schematic diagram of the structure of the winding core inside the battery cell;
[0021] Figure 11 yes Figure 9 Top view at point C in the figure;
[0022] Figure 12 yes Figure 9 Side view of;
[0023] Figure 13 This is the fourth structural diagram of a battery cell provided by this application;
[0024] Figure 14 yes Figure 13 Schematic diagram of the structure of the winding core inside the battery cell;
[0025] Figure 15 yes Figure 13 The top view at D in FIG.
[0026] Figure 16 yes Figure 13 Side view of;
[0027] Figure 17 yes Figure 13 Exploded structural diagram of the first tab group;
[0028] Figure 18 This is a schematic structural diagram of a comparative example provided in the embodiments of the present application;
[0029] Figure 19 yes Figure 18 Schematic diagram of the structure of the winding core inside the battery cell;
[0030] Figure 20 yes Figure 18 The top view at E in FIG.
[0031] Figure 21 yes Figure 18 side view. DETAILED DESCRIPTION
[0032] The following will be combined with the accompanying drawings in the embodiments of this application to clearly describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of this application.
[0033] The terms "first," "second," and the like in this application are used to distinguish similar objects, and are not used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable, where appropriate, so that the embodiments of this application can be implemented in an order other than that illustrated or described herein. Furthermore, the objects distinguished by "first" and "second" generally refer to a class and do not limit the number of objects. For example, the first object can be one or more. Furthermore, "or" in this application represents at least one of the connected objects. For example, the scope of protection for "A or B" covers at least three options: Option 1: includes A but not B; Option 2: includes B but not A; and Option 3: includes both A and B. Furthermore, the terms "A and / or B," "at least one of A and B," and "at least one of A or B" also cover at least the above three options, respectively. The character " / " generally indicates that the objects associated with each other are in an "or" relationship.
[0034] The following describes in detail the battery cells and batteries provided in the embodiments of the present application through some embodiments and their application scenarios in conjunction with the accompanying drawings.
[0035] See Figures 1 to 17 , an embodiment of the present application provides a battery cell, comprising:
[0036] A housing 100 is provided with a receiving cavity 110 therein, and a first opening 120 and a second opening 130 are formed at a first end of the housing 100 and communicate with the receiving cavity 110;
[0037] A winding core 200 is disposed in the accommodating cavity 110;
[0038] A first tab group 300, the first tab group 300 includes a first tab 310 and a second tab 320 of the same polarity, the first tab 310 and the second tab 320 are arranged at intervals along the thickness direction of the winding core 200, and one end of the first tab group 300 is electrically connected to the winding core 200, and the other end of the first tab group 300 extends out of the shell 100 through the first opening 120, the first tab group 300 forms a first step 710 along the thickness direction of the winding core 200, and the first step 710 is located at an edge area of the first tab group 300, the shell 100 is sealed and connected to the first tab group 300, and the area where the first tab group 300 is sealed and connected to the shell 100 includes the area where the first step 710 is located;
[0039] The second electrode tab group 400 includes at least one of a third electrode tab 410 and a fourth electrode tab 420 with the same polarity, and one of the first electrode tab 310 and the third electrode tab 410 is a positive electrode tab and the other is a negative electrode tab; one end of the second electrode tab group 400 is electrically connected to the winding core 200, and the other end of the second electrode tab group 400 extends out of the shell 100 through the second opening 130.
[0040] The battery cell can be used as a battery cell in various electronic devices. The housing 100 can be an aluminum-plastic film shell of the battery cell.
[0041] The winding core 200 includes a positive electrode sheet 210, a separator 220, and a negative electrode sheet 230 stacked in sequence, and the winding core 200 is in a wound shape. Specifically, the winding core 200 can be formed by flattening the stacked positive electrode sheet 210, separator 220, and negative electrode sheet 230, and then winding the entire winding core 200 from one end of the winding core 200 to the other end of the winding core 200 in the longitudinal direction. That is, one end of the winding core 200 in the longitudinal direction is located at the innermost end of the winding core 200, and the other end of the winding core 200 in the longitudinal direction is located at the outermost end of the winding core 200.
[0042] It is understandable that the positive electrode tab can be welded to the positive electrode sheet 210 in the winding core 200 , and the negative electrode tab can be welded to the negative electrode sheet 230 in the winding core 200 .
[0043] The first end of the shell 100 may be an open end. The first opening 120 and the second opening 130 may be openings from which the first tab group 300 and the second tab group 400 extend after the first end is packaged. The first tab group 300 closes the first opening 120 , and the second tab group 400 closes the second opening 130 .
[0044] The above-mentioned battery cell may further include a protective plate, which may include a solder pad, wherein the tabs in the first tab group 300 and the tabs in the second tab group 400 extend from one end of the open end of the shell 100 outside the shell 100, and the tabs in the first tab group 300 and the tabs in the second tab group 400 are respectively electrically connected to the solder pad in the protective plate.
[0045] The above-mentioned sealed connection between the housing 100 and the first tab group 300 may refer to: the outer side wall of the housing 100 surrounding the first tab group 300 is adhered to the outer side wall of the first tab group 300, so that the connection between the first tab group 300 and the first opening 120 of the housing 100 is sealed. The first tab group 300 may include tab glue for sealed connection with the housing 100. Since the area where the first tab group 300 and the housing 100 are sealed includes the area where the first step 710 is located, a portion of the tab glue included in the first tab group 300 may form the surface of the first step 710, so that the housing 100 can cover the surface of the first step 710. The tab glue at the first step 710 is adhered to the surface of the first step 710, thereby achieving the encapsulation of the edge area of the housing 100 and the first tab group 300. The tab glue included in the first tab group 300 may include a first tab glue layer 500 , a third tab glue layer 700 , and a fourth tab glue layer 900 in the embodiment of the present application.
[0046] Since the first tab 310 and the second tab 320 in the first tab group 300 are stacked along the thickness direction of the winding core 200, the thickness dimension of the first tab group 300 is relatively large. If the thickness of the edge of the first tab group 300 is the same as the thickness of other positions of the first tab group 300, a large height difference will result between the edge of the first tab group 300 and other areas on both sides of the first tab group 300. In this way, during the packaging process of the shell 100 and the first tab group 300, the tab glue on both sides of the first tab group 300 may be poorly fused, thereby causing leakage problems, and further making it easy for poor packaging problems to occur on both sides of the first tab group 300.
[0047] It is understood that in some embodiments of the present application, the first stepped portion 710 may be formed only on the edge of one side of the first tab assembly 300. In other embodiments of the present application, one first stepped portion 710 may be formed simultaneously on both sides of the first tab assembly 300. For ease of understanding, the present embodiment uses the example of forming one first stepped portion 710 on each side of the first tab assembly 300 to further illustrate the structure of the battery cell in the present embodiment. In some embodiments of the present application, the thickness of the edge regions on both sides of the first tab assembly 300 is made smaller than the thickness of the central region of the first tab assembly 300, thereby forming one first stepped portion 710 on each side of the first tab assembly 300. Because the thickness of the edge regions on both sides of the first tab assembly 300 is smaller than the thickness of the central region of the first tab assembly 300, the height difference between the first tab assembly 300 and other regions on both sides of the first tab assembly 300 can be reduced, thereby improving the fusion sealing effect between the first stepped portion 710 and the housing 100.
[0048] In some embodiments of the present application, the battery cell may be a three-electrode tab battery cell. In this case, the second electrode tab group 400 includes a third electrode tab 410. That is, the three electrode tabs of the battery cell are the first electrode tab 310, the second electrode tab 320, and the third electrode tab 410. In this case, if the first electrode tab 310 and the second electrode tab 320 are both positive electrode tabs, the third electrode tab 410 is a negative electrode tab. If the first electrode tab 310 and the second electrode tab 320 are both negative electrode tabs, the third electrode tab 410 is a positive electrode tab.
[0049] In some embodiments of the present application, the battery cell may be a three-electrode tab battery cell. In this case, the second electrode tab group 400 includes a fourth electrode tab 420. That is, the three electrode tabs of the battery cell are the first electrode tab 310, the second electrode tab 320, and the fourth electrode tab 420. In this case, if the first electrode tab 310 and the second electrode tab 320 are both positive electrode tabs, the fourth electrode tab 420 is a negative electrode tab. If the first electrode tab 310 and the second electrode tab 320 are both negative electrode tabs, the fourth electrode tab 420 is a positive electrode tab.
[0050] In some embodiments of the present application, the battery cell may be a four-tab battery cell. In this case, the second tab group 400 includes a third tab 410 and a fourth tab 420. That is, the four tabs of the battery cell are the first tab 310, the second tab 320, the third tab 410, and the fourth tab 420. If the first tab 310 and the second tab 320 are both positive tabs, the third tab 410 and the fourth tab 420 are negative tabs. If the first tab 310 and the second tab 320 are both negative tabs, the third tab 410 and the fourth tab 420 are positive tabs.
[0051] In addition, the distance between the first and second electrode tabs 310 and 320 along the length of the core 200 may range from L / 4 to 3L / 4. Accordingly, when the second electrode tab assembly 400 includes a third electrode tab 410 and a fourth electrode tab 420, the distance between the third and fourth electrode tabs 410 and 420 along the length of the core 200 may range from L / 4 to 3L / 4, where L represents the length of the core 200. The length of the core 200 refers to the distance between the two ends of the core 200 in the length direction after the core 200 is flattened.
[0052] For ease of understanding, some embodiments of the present application take the first pole tab 310 and the second pole tab 320 as positive pole tabs, and the third pole tab 410 and the fourth pole tab 420 as negative pole tabs as an example to further explain the structure of the battery cell in the embodiments of the present application. Specifically, since the purpose of setting two positive pole tabs in the embodiments of the present application is to reduce the internal resistance of the battery cell, if the distance between the two positive pole tabs is too close, it will cause some areas in the positive electrode sheet 210 to be far away from both positive pole tabs, thereby causing the internal resistance in the positive electrode sheet 210 to still be large. Based on this, in the embodiments of the present application, by making the distance between the first pole tab 310 and the second pole tab 320 along the length direction of the winding core 200 range from L / 4 to 3L / 4, it can avoid the distance between the two positive pole tabs being too close, which is beneficial to reducing the internal resistance in the positive electrode sheet 210. Accordingly, by making the distance between the third electrode tab 410 and the fourth electrode tab 420 along the length direction of the winding core 200 range from L / 4 to 3L / 4, the distance between the two negative electrode tabs can be avoided from being too close, which is beneficial to reducing the internal resistance in the negative electrode sheet 230.
[0053] See Figure 3 The edge region of the first tab group 300 may refer to the recessed regions on both sides of the first tab group 300, which are also the regions where the first step positions 710 are located. Correspondingly, the middle region of the first tab group 300 is the region between the two first step positions 710. Figure 1 , both sides of the first tab group 300 refer to: both sides of the first tab group 300 in the width direction of the battery cell, wherein the width direction of the battery cell is Figure 1 Horizontal direction in .
[0054] In this embodiment, by making the battery cell include the first tab group 300 and the second tab group 400, since the battery cell can be charged and discharged through the first tab group 300 and the second tab group 400 at the same time, it is beneficial to improve the uniformity of current distribution in the battery cell, thereby reducing the charging time of the battery cell during charging and reducing the temperature rise during the charging process. In addition, since the first pole tab 310 and the second pole tab 320 in the first pole tab group 300 are stacked in the thickness direction of the winding core 200, the thickness dimension of the first pole tab group 300 is relatively large. During the packaging process of the shell 100 and the first pole tab group 300, poor packaging problems are likely to occur on both sides of the first pole tab group 300. Based on this, in an embodiment of the present application, by forming a first step position 710 along the thickness direction of the winding core 200 of the first pole tab group 300, and the first step position 710 is located in the edge area of the first pole tab group 300, the thickness at the edges of both sides of the first pole tab group 300 can be reduced, which is beneficial to improving the packaging effect of the shell 100 and the first pole tab group 300.
[0055] Optionally, when the second pole tab group 400 includes the third pole tab 410 and the fourth pole tab 420, the third pole tab 410 and the fourth pole tab 420 are arranged at intervals along the thickness direction of the winding core 200, and the second pole tab group 400 forms a second step position 810 along the thickness direction of the winding core 200, and the second step position 810 is located in the edge area of the second pole tab group 400, the shell 100 is sealed and connected to the second pole tab group 400, and the area where the second pole tab group 400 is sealed and connected to the shell 100 includes the area where the second step position 810 is located.
[0056] The above-mentioned sealed connection between the housing 100 and the second tab group 400 may mean that the outer wall of the housing 100 surrounding the second tab group 400 is adhered to the outer wall of the second tab group 400, so that the connection between the second tab group 400 and the second opening 130 of the housing 100 is sealed. The second tab group 400 may include tab glue for sealed connection with the housing 100. Since the area where the second tab group 400 is sealed with the housing 100 includes the area where the second step 810 is located, a portion of the tab glue included in the second tab group 400 may form the surface of the second step 810 to facilitate the housing 100 covering the surface of the second step 810. The tab glue at the second step 810 is adhered to the surface of the second step 810, thereby achieving the sealing of the edge area of the housing 100 and the second tab group 400. The tab glue included in the second tab group 400 may include the second tab glue layer 600, the fifth tab glue layer 800, and the sixth tab glue layer in the embodiment of the present application.
[0057] Since the third pole tab 410 and the fourth pole tab 420 in the second pole tab group 400 are stacked along the thickness direction of the winding core 200, the thickness dimension of the second pole tab group 400 is relatively large. If the thickness of the edge of the second pole tab group 400 is the same as the thickness of other positions of the second pole tab group 400, a large height difference will result between the edge of the second pole tab group 400 and other areas on both sides of the second pole tab group 400. In this way, during the packaging process of the shell 100 and the second pole tab group 400, the pole tab glue on both sides of the second pole tab group 400 may be poorly fused, thereby causing leakage problems, and further making it easy for poor packaging problems to occur on both sides of the second pole tab group 400.
[0058] It is understandable that in some embodiments of the present application, the second step position 810 can be formed only on the edge of one side of the second tab group 400. In other embodiments of the present application, one second step position 810 can also be formed on both sides of the second tab group 400 at the same time. For ease of understanding, the embodiment of the present application takes the formation of one second step position 810 on both sides of the second tab group 400 as an example to further explain the structure of the battery cell in the embodiment of the present application. In some embodiments of the present application, the thickness of the edge areas on both sides of the second tab group 400 can be made smaller than the thickness of the middle area of the second tab group 400. Therefore, the height difference between the second tab group 400 and other areas on both sides of the second tab group 400 can be reduced, thereby improving the fusion sealing effect between the second step position 810 and the shell 100.
[0059] See Figure 1 The edge region of the second tab group 400 may refer to the recessed regions on both sides of the second tab group 400, which are also the regions where the second step positions 810 are located. Correspondingly, the middle region of the second tab group 400 is the region between the two second step positions 810. Figure 1 , the two sides of the second tab group 400 refer to: the two sides of the second tab group 400 in the width direction of the battery cell, wherein the width direction of the battery cell is Figure 1 Horizontal direction in .
[0060] In this embodiment, a second step position 810 is formed along the thickness direction of the winding core 200 on the second tab group 400. The second step position 810 is located in the edge area of the second tab group 400, thereby reducing the thickness of the edges on both sides of the second tab group 400, thereby facilitating improving the packaging effect of the shell 100 and the second tab group 400.
[0061] Optionally, the width of the first electrode tab 310 is smaller than or equal to the width of the second electrode tab 320 .
[0062] Correspondingly, the width of the third electrode tab 410 is smaller than or equal to the width of the fourth electrode tab 420 .
[0063] In some embodiments of the present application, the width difference between the first electrode tab 310 and the second electrode tab 320 ranges from 0 mm to 5 mm. Correspondingly, the width difference between the third electrode tab 410 and the fourth electrode tab 420 ranges from 0 mm to 5 mm.
[0064] The width direction of the first pole tab 310, the second pole tab 320, the third pole tab 410 and the fourth pole tab 420 are the same, and the width direction of the first pole tab 310 is the width direction of the battery cell, wherein the width direction of the battery cell is Figure 1 Horizontal direction in .
[0065] In this embodiment, by making the width dimension of the first pole lug 310 smaller than or equal to the width dimension of the second pole lug 320, when the width dimension of the first pole lug 310 is smaller than the width dimension of the second pole lug 320, there is a width difference between the first pole lug 310 and the second pole lug 320, and the first pole lug 310 and the second pole lug 320 in the first pole lug group 300 are arranged at intervals along the thickness direction of the winding core 200. Therefore, by adjusting the relative position between the first pole lug 310 and the second pole lug 320, the thickness of the two side edges of the first pole lug group 300 can be made smaller than the thickness of the middle area of the first pole lug group 300, which is conducive to forming two first step positions 710 on both sides of the first pole lug group 300. Correspondingly, when the width dimension of the first pole tab 310 is equal to the width dimension of the second pole tab 320, the positions of the first pole tab 310 and the second pole tab 320 in the width direction can be relatively staggered to form the first step positions 710 on both sides of the first pole tab group 300, respectively, wherein the width direction is perpendicular to the thickness direction.
[0066] Optionally, the first tab group 300 further includes a first tab adhesive layer 500 , and the first tab 310 and the second tab 320 are connected via the first tab adhesive layer 500 .
[0067] Correspondingly, the second tab group 400 further includes a second tab adhesive layer 600 , and the third tab 410 and the fourth tab 420 are connected via the second tab adhesive layer 600 .
[0068] It is understood that the first tab 310, the first tab adhesive layer 500, and the second tab 320 in the first tab group 300 can be stacked sequentially along the thickness direction of the battery cell. Correspondingly, the third tab 410, the second tab adhesive layer 600, and the fourth tab 420 in the second tab group 400 can be stacked sequentially along the thickness direction of the battery cell.
[0069] It should be noted that the tab glue in the embodiment of the present application can be various common tab glues in battery cells, for example, it can be polypropylene (PP) glue.
[0070] In this embodiment, by making the first pole tab group 300 further include the first pole tab adhesive layer 500, the first pole tab 310 and the second pole tab 320 are connected through the first pole tab adhesive layer 500. In this way, the first pole tab 310 and the second pole tab 320 can be connected to form a whole, and the first pole tab adhesive layer 500 can relatively separate the first pole tab 310 and the second pole tab 320 to avoid a short circuit between the first pole tab 310 and the second pole tab 320.
[0071] Optionally, the first tab adhesive layer 500 includes: a first sub-adhesive layer 510 located on an end surface of the first tab 310 facing one end of the second tab 320, and a second sub-adhesive layer 520 located on an end surface of the second tab 320 facing one end of the first tab 310, wherein the first sub-adhesive layer 510 and the second sub-adhesive layer 520 are bonded together;
[0072] The battery cell further includes a third tab adhesive layer 700 and a fourth tab adhesive layer 900. The third tab adhesive layer 700 is located on a side of the first tab 310 facing away from the second tab 320, and the first tab 310 is bonded to the housing 100 through the third tab adhesive layer 700. The fourth tab adhesive layer 900 is located on a side of the second tab 320 facing away from the first tab 310, and the second tab 320 is bonded to the housing 100 through the fourth tab adhesive layer 900.
[0073] The width dimension of the first sub-glue layer 510 is equal to the width dimension of the third pole ear glue layer 700, and the first sub-glue layer 510 is aligned with the third pole ear glue layer 700, the width dimension of the second sub-glue layer 520 is equal to the width dimension of the fourth pole ear glue layer 900, and the second sub-glue layer 520 is aligned with the fourth pole ear glue layer 900, the width dimension of the first sub-glue layer 510 is smaller than the width dimension of the second sub-glue layer 520, and a first step position 710 is formed on both sides of the connection between the first sub-glue layer 510 and the second sub-glue layer 520.
[0074] See Figure 3In some embodiments of the present application, the first tab 310 is located between the first sub-glue layer 510 and the third tab glue layer 700, and the width of the first sub-glue layer 510 and the width of the third tab glue layer 700 are both greater than the width of the first tab 310, so that both sides of the first sub-glue layer 510 in the width direction can extend from both sides of the first tab 310 in the width direction, and both sides of the third tab glue layer 700 in the width direction can extend from both sides of the first tab 310 in the width direction. In this way, the portions of the first sub-glue layer 510 extending from both sides of the width direction of the first tab 310 can be stacked and bonded with the portions of the third tab glue layer 700 extending from both sides of the width direction of the first tab 310. Accordingly, the second tab 320 is located between the second sub-glue layer 520 and the fourth tab glue layer 900, and the width of the second sub-glue layer 520 and the width of the fourth tab glue layer 900 are both greater than the width of the second tab 320. This allows both sides of the second sub-glue layer 520 to extend from both sides of the width of the second tab 320, and both sides of the fourth tab glue layer 900 to extend from both sides of the width of the second tab 320. In this way, the portion of the second sub-glue layer 520 extending from both sides of the width of the second tab 320 can be stacked and bonded with the portion of the fourth tab glue layer 900 extending from both sides of the width of the second tab 320. This achieves the sequential stacking of the third tab glue layer 700, the first tab glue layer 500, and the fourth tab glue layer 900.
[0075] See Figure 3 Since the width of the first sub-glue layer 510 is smaller than the width of the second sub-glue layer 520, and the first sub-glue layer 510 and the second sub-glue layer 520 are stacked, it is only necessary to make the two sides of the first sub-glue layer 510 in the width direction be located on the inner sides of the two sides of the second sub-glue layer 520 in the width direction, so that the first step positions 710 on both sides of the first tab group 300 can be formed at the connection between the first sub-glue layer 510 and the second sub-glue layer 520.
[0076] Correspondingly, the fourth tab adhesive layer 900 includes: a third sub-adhesive layer located on the end surface of the third tab 410 facing one end of the fourth tab 420, and a fourth sub-adhesive layer located on the end surface of the fourth tab 420 facing one end of the third tab 410, wherein the third sub-adhesive layer is bonded to the fourth sub-adhesive layer;
[0077] The battery cell further includes a fifth tab adhesive layer 800 and a sixth tab adhesive layer, wherein the fifth tab adhesive layer 800 is located on a side of the third tab 410 facing away from the fourth tab 420, and the third tab 410 is bonded to the housing 100 through the third tab adhesive layer 700, and the sixth tab adhesive layer is located on a side of the fourth tab 420 facing away from the third tab 410, and the fourth tab 420 is bonded to the housing 100 through the sixth tab adhesive layer;
[0078] The width dimension of the third sub-glue layer is equal to the width dimension of the fifth tab glue layer 800, and the third sub-glue layer is aligned with the fifth tab glue layer 800, the width dimension of the fourth sub-glue layer is equal to the width dimension of the sixth tab glue layer, and the fourth sub-glue layer is aligned with the sixth tab glue layer, the width dimension of the third sub-glue layer is smaller than the width dimension of the fourth sub-glue layer, and a second step position 810 is formed on both sides of the connection between the third sub-glue layer and the fourth sub-glue layer.
[0079] In some embodiments of the present application, the third pole tab 410 is located between the third sub-glue layer and the third pole tab glue layer 700, and the width dimension of the third sub-glue layer and the width dimension of the third pole tab glue layer 700 are both larger than the width dimension of the third pole tab 410, so that the two sides of the third sub-glue layer in the width direction can extend from the two sides of the width direction of the third pole tab 410, and the two sides of the third pole tab glue layer 700 in the width direction can extend from the two sides of the width direction of the third pole tab 410. In this way, the portion of the third sub-glue layer extending from the two sides of the width direction of the third pole tab 410 can be stacked and bonded with the portion of the third pole tab glue layer 700 extending from the two sides of the width direction of the third pole tab 410. Accordingly, the fourth tab 420 is located between the fourth sub-glue layer and the fourth tab glue layer 900, and the width of the fourth sub-glue layer and the width of the fourth tab glue layer 900 are both greater than the width of the fourth tab 420. This allows both sides of the fourth sub-glue layer in the width direction to extend from both sides of the width direction of the fourth tab 420, and both sides of the fourth tab glue layer 900 in the width direction to extend from both sides of the width direction of the fourth tab 420. In this way, the portion of the fourth sub-glue layer extending from both sides of the width direction of the fourth tab 420 can be stacked and bonded with the portion of the fourth tab glue layer 900 extending from both sides of the width direction of the fourth tab 420. This achieves the sequential stacking of the third tab glue layer 700, the third tab glue layer 700, and the fourth tab glue layer 900.
[0080] Since the width dimension of the third sub-glue layer is smaller than the width dimension of the fourth sub-glue layer, and the third sub-glue layer and the fourth sub-glue layer are stacked, it is only necessary to make the two sides of the width direction of the third sub-glue layer respectively located on the inner sides of the two sides of the width direction of the fourth sub-glue layer, so that the second step positions 810 on both sides of the third electrode tab 410 group can be formed at the connection between the third sub-glue layer and the fourth sub-glue layer.
[0081] See Figures 9 to 12 , in some embodiments of the present application, is a structural diagram of the connection between the first pole tab 310 and the second pole tab 320 when the width of the first pole tab 310 is equal to the width of the second pole tab 320. Figures 9 to 12 In the illustrated embodiment, the widths of the two tabs in the first tab group 300 are consistent, the second sub-glue layer 520 and the fourth tab glue layer 900 are the tab glue layers on the second tab 320, and the third tab glue layer 700 and the first sub-glue layer 510 are the tab glue layers on the first tab 310, that is, the widths of the tab glue layers on the two tabs are inconsistent, the width of the tab glue layer on the first tab 310 is 7 mm to 9 mm, and the width of the tab glue layer on the second tab 320 is 2 mm to 5 mm wider than the width of the tab glue layer on the first tab 310. The center lines of the tab glue layers of the two tabs overlap. After stacking, the edges of the tab glue layers of the two tabs do not overlap, forming two thickness steps, which can avoid poor fusion and leakage caused by excessive thickness difference of a single step when the four-layer tab glue layer and the aluminum-plastic film PP after pre-welding are fused.
[0082] Accordingly, see Figures 1 to 4 , in some embodiments of the present application, it is a structural diagram of the connection between the first pole tab 310 and the second pole tab 320 when the width of the first pole tab 310 is smaller than the width of the second pole tab 320 .
[0083] In this embodiment, by making the width dimension of the first sub-glue layer 510 equal to the width dimension of the third pole tab glue layer 700, and the first sub-glue layer 510 is aligned with the third pole tab glue layer 700, the width dimension of the second sub-glue layer 520 is equal to the width dimension of the fourth pole tab glue layer 900, and the second sub-glue layer 520 is aligned with the fourth pole tab glue layer 900, the width dimension of the first sub-glue layer 510 is smaller than the width dimension of the second sub-glue layer 520, and the first step position 710 on both sides of the first pole tab group 300 is formed at the connection between the first sub-glue layer 510 and the second sub-glue layer 520. In this way, a first step position 710 can be formed on both sides of the first pole tab group 300.
[0084] Optionally, the thickness of the first sub-glue layer 510 is equal to the thickness of the second sub-glue layer 520 , and the thickness of the third tab glue layer 700 is equal to the thickness of the fourth tab glue layer 900 .
[0085] Correspondingly, the thickness of the third sub-glue layer is equal to the thickness of the fourth sub-glue layer, and the thickness of the fifth tab glue layer 800 is equal to the thickness of the sixth tab glue layer.
[0086] The thickness of the first sub-glue layer 510 and the third tab glue layer 700 can be set as needed.
[0087] In this embodiment, since the thickness of the first sub-glue layer 510 is equal to the thickness of the second sub-glue layer 520, the bonding effect between the first sub-glue layer 510 and the second sub-glue layer 520 can be improved. Accordingly, by making the thickness of the third tab glue layer 700 equal to the thickness of the fourth tab glue layer 900, the bonding effect between the two end surfaces connecting the first tab group 300 and the housing 100 can be made relatively consistent, thereby facilitating an improved packaging effect between the first tab group 300 and the housing 100.
[0088] Optionally, the thickness of the first sub-glue layer 510 is smaller than the thickness of the third tab glue layer 700 .
[0089] Correspondingly, the thickness of the third sub-glue layer is smaller than the thickness of the fifth tab glue layer 800 .
[0090] In some embodiments of the present application, the thickness of the third tab adhesive layer 700 is 10 μm to 30 μm thicker than the thickness of the first sub-adhesive layer 510. In the embodiments of the present application, the thickness of the third tab adhesive layer 700 ranges from 800 μm to 100 μm, and the thickness of the first sub-adhesive layer 510 ranges from 50 μm to 70 μm. In the embodiments of the present application, by making the thickness of the first sub-adhesive layer 510 thinner than the thickness of the third tab adhesive layer 700, the overall thickness of the first tab assembly 300 is reduced, thereby further improving the packaging effect between the first tab assembly 300 and the housing 100.
[0091] Specifically, since the third tab adhesive layer 700 and the fourth tab adhesive layer 900 are located on the outside of the first tab group 300 and are used to bond with the housing 100, and since the thickness of the third tab adhesive layer 700 and the fourth tab adhesive layer 900 are relatively thin, in order to achieve a better fusion effect of the tab adhesive layer connecting the first tab group 300 and the housing 100, the thickness of the third tab adhesive layer 700 and the fourth tab adhesive layer 900 cannot be reduced. The first sub-adhesive layer 510 and the second sub-adhesive layer 520 are located on the inside of the first tab group 300, and the first sub-adhesive layer 510 and the second sub-adhesive layer 520 are fused together, and the two themselves have a good fusion effect. Therefore, the thickness of the first sub-adhesive layer 510 and the second sub-adhesive layer 520 is appropriately reduced, and the first sub-adhesive layer 510 and the second sub-adhesive layer 520 are also deliberately satisfied with the overflow glue fusion requirement. Based on this, in the embodiment of the present application, by making the thickness of the first sub-glue layer 510 smaller than the thickness of the third tab glue layer 700 , it is beneficial to reduce the overall thickness of the first tab group 300 .
[0092] Accordingly, since the fifth and sixth tab adhesive layers 800 and 600 are located on the outside of the second tab group 400 and are used to bond with the housing 100, and since the thickness of the fifth and sixth tab adhesive layers is relatively thin, in order to achieve a better fusion effect of the tab adhesive layers connecting the second tab group 400 and the housing 100, the thickness of the fifth and sixth tab adhesive layers cannot be reduced. The third and fourth sub-adhesive layers are located on the inside of the second tab group 400, and the third and fourth sub-adhesive layers are fused together, and the two themselves have a better fusion effect. Therefore, the thickness of the third and fourth sub-adhesive layers is appropriately reduced, and the third and fourth sub-adhesive layers are also deliberately designed to meet the requirements of overflow fusion. Based on this, in the embodiment of the present application, by making the thickness of the third sub-adhesive layer less than the thickness of the fifth tab adhesive layer 800, it is beneficial to achieve a reduction in the overall thickness of the second tab group 400.
[0093] In this embodiment, by making the thickness of the first sub-glue layer 510 smaller than the thickness of the third tab glue layer 700 , the overall thickness of the first tab group 300 can be reduced, thereby improving the packaging effect between the first tab group 300 and the housing 100 .
[0094] Optionally, the battery cell further includes a third tab adhesive layer 700 and a fourth tab adhesive layer 900, wherein the third tab adhesive layer 700 is located on a side of the first tab 310 facing away from the second tab 320, and the first tab 310 is bonded to the housing 100 through the third tab adhesive layer 700, and the fourth tab adhesive layer 900 is located on a side of the second tab 320 facing away from the first tab 310, and the second tab 320 is bonded to the housing 100 through the fourth tab adhesive layer 900;
[0095] The third tab adhesive layer 700, the first tab adhesive layer 500 and the fourth tab adhesive layer 900 are stacked in sequence, the width of the first tab adhesive layer 500 is equal to the width of the fourth tab adhesive layer 900, and the first tab adhesive layer 500 is aligned with the fourth tab adhesive layer 900, the width of the third tab adhesive layer 700 is smaller than the width of the first tab adhesive layer 500, and a first step position 710 is formed on both sides of the connection between the third tab adhesive layer 700 and the first tab adhesive layer 500.
[0096] In some embodiments of the present application, before the first tab group 300 is packaged, the first tab adhesive layer 500 may be provided on the side of the first tab 310 facing the second tab 320, while the tab adhesive may not be provided on the side of the second tab 320 facing the first tab 310. During the packaging process, the first tab 310 may be bonded to the second tab 320 via the first tab adhesive layer 500 on its surface. Correspondingly, in other embodiments of the present application, before the first tab group 300 is packaged, the first tab adhesive layer 500 may be provided on the side of the second tab 320 facing the first tab 310, while the tab adhesive may not be provided on the side of the first tab 310 facing the second tab 320. During the packaging process, the second tab 320 may be bonded to the first tab 310 via the first tab adhesive layer 500 on its surface.
[0097] See Figure 7The first tab 310 is located between the first tab adhesive layer 500 and the third tab adhesive layer 700, and the width of the first tab adhesive layer 500 and the width of the third tab adhesive layer 700 are both greater than the width of the first tab 310, so that both sides of the first tab adhesive layer 500 in the width direction can extend from both sides of the first tab 310 in the width direction, and both sides of the third tab adhesive layer 700 in the width direction can extend from both sides of the first tab 310 in the width direction. In this way, the portions of the first tab adhesive layer 500 extending from both sides of the width direction of the first tab 310 can be stacked and bonded with the portions of the third tab adhesive layer 700 extending from both sides of the width direction of the first tab 310. Accordingly, the second tab 320 is located between the first tab adhesive layer 500 and the fourth tab adhesive layer 900, and the widths of the first tab adhesive layer 500 and the fourth tab adhesive layer 900 are both greater than the width of the second tab 320. This allows both sides of the first tab adhesive layer 500 to extend from both sides of the width of the second tab 320, and both sides of the fourth tab adhesive layer 900 to extend from both sides of the width of the second tab 320. In this way, the portions of the first tab adhesive layer 500 extending from both sides of the width of the second tab 320 can be stacked and bonded to the portions of the fourth tab adhesive layer 900 extending from both sides of the width of the second tab 320. This results in the third tab adhesive layer 700, the first tab adhesive layer 500, and the fourth tab adhesive layer 900 being stacked in sequence.
[0098] Correspondingly, the battery cell further includes a fifth tab adhesive layer 800 and a sixth tab adhesive layer, the fifth tab adhesive layer 800 being located on the side of the third tab 410 facing away from the fourth tab 420, and the third tab 410 being bonded to the housing 100 via the fifth tab adhesive layer 800, and the sixth tab adhesive layer being located on the side of the fourth tab 420 facing away from the third tab 410, and the fourth tab 420 being bonded to the housing 100 via the sixth tab adhesive layer;
[0099] The fifth tab adhesive layer 800, the second tab adhesive layer 600 and the sixth tab adhesive layer are stacked in sequence, the width of the second tab adhesive layer 600 is equal to the width of the sixth tab adhesive layer, and the second tab adhesive layer 600 is aligned with the sixth tab adhesive layer, the width of the fifth tab adhesive layer 800 is smaller than the width of the second tab adhesive layer 600, and a second step position 810 is formed on both sides of the fifth tab adhesive layer 800 and the second tab adhesive layer 600.
[0100] In some embodiments of the present application, before the second tab group 400 is packaged, the second tab adhesive layer 600 may be provided on the side of the third tab 410 facing the fourth tab 420, while the tab adhesive may not be provided on the side of the fourth tab 420 facing the third tab 410. During the packaging process, the third tab 410 may be bonded to the fourth tab 420 via the second tab adhesive layer 600 on its surface. Correspondingly, in other embodiments of the present application, before the second tab group 400 is packaged, the second tab adhesive layer 600 may be provided on the side of the fourth tab 420 facing the third tab 410, while the tab adhesive may not be provided on the side of the third tab 410 facing the fourth tab 420. During the packaging process, the fourth tab 420 may be bonded to the third tab 410 via the second tab adhesive layer 600 on its surface.
[0101] The third pole tab 410 is located between the second pole tab adhesive layer 600 and the fifth pole tab adhesive layer 800, and the width of the second pole tab adhesive layer 600 and the width of the fifth pole tab adhesive layer 800 are both greater than the width of the third pole tab 410, so that both sides of the second pole tab adhesive layer 600 in the width direction can extend from both sides of the width direction of the third pole tab 410, and both sides of the fifth pole tab adhesive layer 800 in the width direction can extend from both sides of the width direction of the third pole tab 410. In this way, the portions of the second pole tab adhesive layer 600 extending from both sides of the width direction of the third pole tab 410 can be stacked and bonded with the portions of the fifth pole tab adhesive layer 800 extending from both sides of the width direction of the third pole tab 410. Accordingly, the fourth tab 420 is located between the second tab adhesive layer 600 and the sixth tab adhesive layer, and the widths of the second tab adhesive layer 600 and the sixth tab adhesive layer are both greater than the width of the fourth tab 420. This allows both sides of the second tab adhesive layer 600 in the width direction to extend from both sides of the fourth tab 420, and both sides of the sixth tab adhesive layer in the width direction to extend from both sides of the fourth tab 420. In this way, the portion of the second tab adhesive layer 600 extending from both sides of the width direction of the fourth tab 420 can be stacked and bonded with the portion of the sixth tab adhesive layer extending from both sides of the width direction of the fourth tab 420. This results in the fifth tab adhesive layer 800, the second tab adhesive layer 600, and the sixth tab adhesive layer being stacked in sequence.
[0102] See Figures 13 to 17 , in some embodiments of the present application, is a structural diagram of the connection between the first pole tab 310 and the second pole tab 320 when the width of the first pole tab 310 is equal to the width of the second pole tab 320. Figures 13 to 17In the illustrated embodiment, the widths of the two tabs in the first tab group 300 are consistent. The first tab adhesive layer 500 and the fourth tab adhesive layer 900 are tab adhesive layers on the second tab 320, and the third tab adhesive layer 700 is tab adhesive layers on the first tab 310. That is, the tab adhesive layers on the two tabs have different widths. The first tab 310 has a tab adhesive layer on only one side, and the width of the tab adhesive layer is 7mm to 9mm. The second tab 320 has tab adhesive layers on both sides, and the width of the tab adhesive layer on the second tab 320 is 2mm to 5mm wider than the width of the tab adhesive layer on the first tab 310. The center lines of the tab adhesive layers of the two tabs overlap. After stacking, the edges of the tab adhesive layers of the two tabs do not overlap, forming two thickness steps. This can prevent the three-layer tab adhesive layer from being fused with the aluminum-plastic film PP after pre-welding due to the excessive thickness difference of a single step, resulting in poor fusion and leakage. Accordingly, please refer to Figures 5 to 8 , in some embodiments of the present application, it is a structural diagram of the connection between the first pole tab 310 and the second pole tab 320 when the width of the first pole tab 310 is smaller than the width of the second pole tab 320 .
[0103] In this embodiment, the third tab adhesive layer 700, the first tab adhesive layer 500 and the fourth tab adhesive layer 900 are stacked in sequence, the width of the first tab adhesive layer 500 is equal to the width of the fourth tab adhesive layer 900, and the first tab adhesive layer 500 is aligned with the fourth tab adhesive layer 900, the width of the third tab adhesive layer 700 is smaller than the width of the first tab adhesive layer 500, and the connection between the third tab adhesive layer 700 and the first tab adhesive layer 500 forms the first step position 710 on both sides of the first tab group 300. In this way, a first step position 710 can be formed on both sides of the first tab group 300.
[0104] Optionally, the thickness of the third tab adhesive layer 700 is equal to the thickness of the fourth tab adhesive layer 900 , and the thickness of the first tab adhesive layer 500 is greater than the thickness of the third tab adhesive layer 700 .
[0105] Correspondingly, the thickness of the fifth tab adhesive layer 800 is equal to the thickness of the sixth tab adhesive layer, and the thickness of the second tab adhesive layer 600 is greater than the thickness of the fifth tab adhesive layer 800 .
[0106] In some embodiments of the present application, the thickness of the first tab adhesive layer 500 may be 0-30 μm thicker than the thickness of the third tab adhesive layer 700. Correspondingly, the thickness of the second tab adhesive layer 600 may be 0-30 μm thicker than the thickness of the fifth tab adhesive layer 800.
[0107] In this embodiment, since the first tab group 300 only includes the first tab adhesive layer 500, the third tab adhesive layer 700 and the fourth tab adhesive layer 900, relative to Figures 1 to 4 In the illustrated embodiment, the first tab group 300 is required to include four tab adhesive layers, namely, the first sub-adhesive layer 510, the second sub-adhesive layer 520, the third tab adhesive layer 700, and the fourth tab adhesive layer 900. This helps reduce the thickness of the tab adhesive in the first tab group 300, thereby further reducing the thickness of the first tab group 300 and improving the packaging effect of the first tab group 300. Furthermore, since only one tab adhesive layer is included between the first tab 310 and the second tab 320, the thickness of the first tab adhesive layer 500 is greater than the thickness of the third tab adhesive layer 700, thereby improving the fusion effect of the tab adhesive between the first tab 310 and the second tab 320.
[0108] Optionally, the melting point of the third tab adhesive layer 700 is equal to the melting point of the fourth tab adhesive layer 900 , and the melting point of the first tab adhesive layer 500 is lower than the melting point of the third tab adhesive layer 700 .
[0109] Accordingly, the melting point of the fifth tab adhesive layer 800 is equal to the melting point of the sixth tab adhesive layer, and the melting point of the second tab adhesive layer 600 is lower than the melting point of the fifth tab adhesive layer 800 .
[0110] It is understandable that the melting point of the tab glue can be changed by changing the material or internal molecular chain structure of the tab glue, thereby obtaining tab glues with different melting points.
[0111] In some embodiments of the present application, the melting point of the first tab glue 310 may be in the range of 110° C. to 130° C., and the melting point of the third tab glue layer 700 may be in the range of 130° C. to 140° C. Correspondingly, the melting point of the second tab glue 320 may be in the range of 110° C. to 130° C., and the melting point of the fifth tab glue layer 800 may be in the range of 130° C. to 140° C.
[0112] Specifically, during the packaging process of the first tab group 300, the first tab 310 and the second tab 320 are usually stacked together first, and then two metal heating blocks are used to clamp the two stacked tabs. The heating blocks directly contact the tab glue layer located on the outer surface of the first tab group 300, that is, the heating blocks directly contact the third tab glue layer 700 and the fourth tab glue layer 900. Then, heat is conducted from the outside to the inside to the tab glue layer inside the first tab group 300, wherein the first tab glue layer 500 is the tab glue layer inside the first tab group 300. Therefore, the first tab glue layer 500 located inside the first tab group 300 is subjected to relatively less heat. In order to increase the fusion effect between the tab glues on the inside, it is usually necessary to increase the amount of melted glue overflow of the inner tab glue. There are two solutions to achieve this effect: one is to increase the heat transferred from the heating block, and the other is to lower the melting point of the inner tab glue so that it can also increase the amount of melted glue overflow at a lower temperature. However, due to the limitation that increasing the heat of the heating block may cause the outer ear glue to melt severely due to direct contact with the heating block, resulting in poor appearance, the embodiment of the present application sets the inner ear glue to a low melting point so as not to affect the appearance of the outer ear glue.
[0113] In the embodiment of the present application, for the tabs in the first tab group 300 and the second tab 320, the tab glue on both sides of a single tab has different melting points and thicknesses. The high melting point of the tab glue on one side is designed to be 130°C to 140°C, and the low melting point of the tab glue on the other side is designed to be 110°C to 130°C. The low melting point tab glue is placed on the inside to solve the problem of poor fusion of the two tabs when pre-welding the tab glue. The high melting point tab glue is 10um to 30um thicker than the low melting point tab glue, in order to reduce the overall thickness of the tab glue after stacking. The thickness of the high melting point tab glue on the outside is 80um to 100um, and the low melting point tab glue on the inside is designed to be 50 to 70um. The design purpose is that the outer tab glue is directly fused with the aluminum-plastic film PP, and because the thickness of PP is relatively thin, in order to achieve a good fusion interface, the fusion is mainly achieved through the overflow glue bite after the tab glue and the PP layer melt each other, and the thickness of the outer tab glue cannot be reduced. The two inner tab glues fuse the two tabs together. Due to their low melting point, the thickness of the two tab glues can be designed to be thinner to meet the requirements of overflow fusion. Reducing the overall tab glue thickness can reduce the step where the entire tab fuses with the aluminum-plastic film PP, further improving the fusion and sealing effect of the step edge.
[0114] In this embodiment, by making the melting point of the third tab adhesive layer 700 equal to the melting point of the fourth tab adhesive layer 900, and the melting point of the first tab adhesive layer 500 is lower than the melting point of the third tab adhesive layer 700, it is possible to ensure that the first tab adhesive layer 500 has a better fusion effect while ensuring that the appearance of the third tab adhesive layer 700 and the fourth tab adhesive layer 900 are not affected.
[0115] Optionally, the first step positions 710 on both sides of the first electrode tab group 300 are symmetrically arranged on both sides of the first electrode tab 310 .
[0116] Correspondingly, the second step positions 810 on both sides of the second electrode tab group 400 are symmetrically arranged on both sides of the third electrode tab 410 .
[0117] In this embodiment, since the first step positions 710 on both sides of the first tab group 300 are symmetrically arranged on both sides of the first tab 310, that is, the structures of the first step positions 710 on both sides of the first tab group 300 are symmetrical, it can be ensured that the first step positions 710 on both sides of the first tab group 300 have a good packaging effect, avoiding the problem that one side has a better packaging effect and the other side has a poor packaging effect due to the different structures of the first step positions 710 on both sides.
[0118] Please refer to Table 1 below for some examples of this application. Figure 3 、 Figure 7 、 Figure 11 、 Figure 15 The illustrated embodiment, and Figures 18 to 21 The comparison case shown in the figure was tested and the test results were compared. Figures 18 to 21 The main structural features of the comparative example shown are: the first tab group 300 includes two stacked positive tabs, the second tab group 400 includes two stacked negative tabs, the two positive tabs in the first tab group 300 have the same tab width, the two negative tabs in the second tab group 400 have the same tab width, and the first sub-glue layer 510, the second sub-glue layer 520, the third tab glue layer 700, the fourth tab glue layer 900, the fifth tab glue layer 800, and the sixth tab glue layer are all of uniform width and thickness. The tab glue width is 6 mm to 12 mm, the thickness of each single tab glue layer is 50 μm to 100 μm, and the melting point of the tab glue is a conventional high melting point design, for example, the melting point of the tab glue is 130°C to 140°C.
[0119] Table 1:
[0120]
[0121]
[0122] As can be seen from Table 1, Figures 9 to 12 The embodiment shown is optimally designed to meet packaging requirements.
[0123] An embodiment of the present application also provides a battery, comprising the battery cell described in the above embodiment.
[0124] In this embodiment, since the battery includes the battery cells described in the above embodiments, the battery can implement the various processes of the battery cells in the above embodiments and has the same beneficial effects. To avoid repetition, they will not be described here.
[0125] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of this application, ordinary technicians in this field can also make many forms without departing from the purpose of this application and the scope of protection of the claims, all of which are within the protection of this application.
Claims
1. A battery cell, characterized in that: include: A housing, wherein a housing is provided with a housing cavity, and a first end of the housing is provided with a first opening and a second opening communicating with the housing cavity; a winding core, the winding core being disposed in the accommodating cavity; a first tab group, the first tab group including a first tab and a second tab of the same polarity, the first tab and the second tab being arranged at intervals along the thickness direction of the winding core, one end of the first tab group being electrically connected to the winding core, the other end of the first tab group extending out of the shell through the first opening, the first tab group forming a first step along the thickness direction of the winding core, the first step being located at an edge region of the first tab group, the shell being sealedly connected to the first tab group, and the region where the first tab group is sealedly connected to the shell including the region where the first step is located; A second electrode tab group, wherein the second electrode tab group includes at least one of a third electrode tab and a fourth electrode tab with the same polarity, wherein one of the first electrode tab and the third electrode tab is a positive electrode tab and the other is a negative electrode tab; one end of the second electrode tab group is electrically connected to the winding core, and the other end of the second electrode tab group extends out of the shell through the second opening.
2. The battery cell according to claim 1, characterized in that In the case where the second pole tab group includes the third pole tab and the fourth pole tab, the third pole tab and the fourth pole tab are arranged at intervals along the thickness direction of the winding core, and the second pole tab group forms a second step position along the thickness direction of the winding core, and the second step position is located in the edge area of the second pole tab group. The shell is sealed and connected to the second pole tab group, and the area where the second pole tab group is sealed and connected to the shell includes the area where the second step position is located.
3. The battery cell according to claim 1, characterized in that The width of the first electrode tab is smaller than or equal to the width of the second electrode tab.
4. The battery cell according to claim 3, characterized in that The first tab group further includes a first tab adhesive layer, and the first tab and the second tab are connected via the first tab adhesive layer.
5. The battery cell according to claim 4, characterized in that: The first tab adhesive layer includes: a first sub-adhesive layer located on an end surface of the first tab facing one end of the second tab, and a second sub-adhesive layer located on an end surface of the second tab facing one end of the first tab, wherein the first sub-adhesive layer is bonded to the second sub-adhesive layer; The battery cell further includes a third tab adhesive layer and a fourth tab adhesive layer, wherein the third tab adhesive layer is located on a side of the first tab facing away from the second tab, and the first tab is bonded to the housing via the third tab adhesive layer, and the fourth tab adhesive layer is located on a side of the second tab facing away from the first tab, and the second tab is bonded to the housing via the fourth tab adhesive layer; The width dimension of the first sub-glue layer is equal to the width dimension of the third tab glue layer, and the first sub-glue layer is aligned with the third tab glue layer, the width dimension of the second sub-glue layer is equal to the width dimension of the fourth tab glue layer, and the second sub-glue layer is aligned with the fourth tab glue layer, the width dimension of the first sub-glue layer is smaller than the width dimension of the second sub-glue layer, and a first step position is formed on both sides of the connection between the first sub-glue layer and the second sub-glue layer.
6. The battery cell according to claim 5, characterized in that The thickness of the first sub-glue layer is equal to the thickness of the second sub-glue layer, and the thickness of the third tab glue layer is equal to the thickness of the fourth tab glue layer.
7. The battery cell according to claim 5 or 6, characterized in that: The thickness of the first sub-glue layer is smaller than the thickness of the third tab glue layer.
8. The battery cell according to claim 4, characterized in that The battery cell further includes a third tab adhesive layer and a fourth tab adhesive layer, wherein the third tab adhesive layer is located on a side of the first tab facing away from the second tab, and the first tab is bonded to the housing via the third tab adhesive layer, and the fourth tab adhesive layer is located on a side of the second tab facing away from the first tab, and the second tab is bonded to the housing via the fourth tab adhesive layer; The third pole tab adhesive layer, the first pole tab adhesive layer and the fourth pole tab adhesive layer are stacked in sequence, the width of the first pole tab adhesive layer is equal to the width of the fourth pole tab adhesive layer, and the first pole tab adhesive layer is aligned with the fourth pole tab adhesive layer, the width of the third pole tab adhesive layer is smaller than the width of the first pole tab adhesive layer, and a first step is formed on both sides of the connection between the third pole tab adhesive layer and the first pole tab adhesive layer.
9. The battery cell according to claim 8, characterized in that The thickness of the third tab adhesive layer is equal to the thickness of the fourth tab adhesive layer, and the thickness of the first tab adhesive layer is greater than the thickness of the third tab adhesive layer.
10. The battery cell according to any one of claims 5 to 9, characterized in that: The melting point of the third tab adhesive layer is equal to the melting point of the fourth tab adhesive layer, and the melting point of the first tab adhesive layer is lower than the melting point of the third tab adhesive layer.
11. A battery, characterized in that: A battery cell comprising the battery cell according to any one of claims 1 to 10.