Battery cell, battery and electric equipment
By designing a bent section in the tab connection structure that passes through a perforation and connects to the adjacent tab metal layer, the problem of the non-conductivity of the metals on both sides of the composite foil is solved, thereby improving the energy density and safety performance of lithium-ion batteries.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHENZHEN HIGHPOWER TECH CO LTD
- Filing Date
- 2025-05-14
- Publication Date
- 2026-04-24
AI Technical Summary
In existing technologies, effective electrical conductivity cannot be achieved between the metals on both sides of the composite foil, which affects the energy density and safety performance of lithium-ion batteries.
Design a tab connection structure, wherein the first tab has a bending part and the second tab has a through hole. The bending part passes through the through hole in the thickness direction of the battery cell and connects with the metal layer of the adjacent tab, so as to realize that the two tab metal layers of the composite foil tab are mutually conductive.
Effective conductivity between the two tab metal layers of the composite foil tab is achieved, improving the energy density and safety performance of lithium-ion batteries.
Smart Images
Figure CN224164229U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of battery technology, and in particular relates to a battery cell, a battery and an electrical device. Background Technology
[0002] In the new energy consumer market, lithium-ion batteries have rapidly occupied the 3C digital consumer market, the new energy vehicle market, and the energy storage application market due to their high energy density. With the development of the industry, the requirements for the electrical energy stored per unit mass of lithium-ion batteries are also getting higher and higher, that is, the requirements for the energy density of batteries are getting higher and higher.
[0003] To improve the energy density of lithium-ion batteries, composite current collectors are often used instead of traditional metal foil current collectors. Composite current collectors have a lower areal density, which reduces the weight of the current collector and thus increases the energy density of the battery. On the other hand, because polymer materials have high ductility, when a lithium-ion battery is impacted by a foreign object, the polymer material can wrap the fracture surface, thereby preventing the fracture from piercing the separator and causing a short circuit, reducing the risk of thermal runaway and improving the safety performance of lithium-ion batteries. However, due to the low conductivity of polymer materials, effective conductivity cannot be achieved between the tab metal layers on both sides of the polymer material. Utility Model Content
[0004] This utility model provides a battery cell to solve the problem in related technologies where effective electrical conductivity cannot be achieved between the metals on both sides of a composite foil.
[0005] The battery cell of this embodiment includes a first polarity electrode, a second polarity electrode, and a separator. At least one of the first polarity electrode and the second polarity electrode includes a tab connection structure. The tab connection structure includes a plurality of composite foil tabs, and the plurality of composite foil tabs include first tabs and second tabs alternately arranged in the thickness direction of the battery cell.
[0006] The first electrode includes a first electrode substrate layer and a first electrode metal layer and a second electrode metal layer disposed on both sides of the first electrode substrate layer;
[0007] The second electrode includes a second electrode substrate layer and a third electrode metal layer and a fourth electrode metal layer disposed on both sides of the second electrode substrate layer;
[0008] The first electrode tab has the bent portion, and the second electrode tab has the perforation;
[0009] In the thickness direction of the battery cell, the free end of the bent portion of the first tab located on one side of the second tab passes through the perforation of the second tab and extends to the other side of the second tab;
[0010] The second electrode metal layer of the first electrode located on one side of the second electrode is connected to the third electrode metal layer of the second electrode, and the first electrode metal layer of the first electrode located on the other side of the second electrode is connected to the fourth electrode metal layer of the second electrode.
[0011] The first electrode metal layer of the portion of the bent part located on the other side of the second electrode is connected to the fourth electrode metal layer of the second electrode.
[0012] The portion of the bent section located on the other side of the second electrode tab has its second electrode tab metal layer connected to the first electrode tab metal layer located on the other side of the second electrode tab.
[0013] Thus, the first tab metal layer, the second tab metal layer, the third tab metal layer, and the fourth tab metal layer are interconnected, thereby achieving the effect that the two tab metal layers of the composite foil tab are mutually conductive and all tab metal layers of adjacent composite foil tabs are mutually conductive, thereby achieving the effect that the tab metal layers on both sides of the composite foil are mutually conductive.
[0014] In some embodiments, the ratio between the size of the perforation in the width direction of the second electrode tab and the width of the second electrode tab is 0.1-0.9.
[0015] In some embodiments, the ratio between the size of the perforation along the length of the second electrode tab and the width of the second electrode tab is 0.1-0.8.
[0016] In some embodiments, the ratio between the dimension of the bent portion in the width direction of the second tab and the dimension of the perforation in the width direction of the second tab is 0.5-0.9.
[0017] In some embodiments, the ratio between the center of the perforation and one end of the second electrode in the length direction of the second electrode tab and the length direction of the second electrode tab is 0.1-0.9.
[0018] In some embodiments, the bent portion of the first electrode tab forms a receiving groove on the first electrode tab after bending, and the bent portion of the first electrode tab located on one side of the second electrode tab is adapted to fit into the receiving groove on the first electrode tab located on the other side of the second electrode tab.
[0019] In some embodiments, the battery cell is a wound battery cell, wherein the first polarity electrode, the separator, and the second polarity electrode are stacked and wound along the winding direction to form the wound battery cell.
[0020] In some embodiments, the battery cell is a laminated battery cell, wherein the first polarity electrode, the separator, and the second polarity electrode are stacked to form the laminated battery cell.
[0021] This utility model embodiment also provides a battery.
[0022] The battery of this utility model embodiment includes the battery cell described in the above embodiment.
[0023] This utility model embodiment also provides an electrical device.
[0024] The electrical equipment in this embodiment includes the battery described in the above embodiment. Attached Figure Description
[0025] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model 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.
[0026] Figure 1 This is a schematic diagram of the structure of the battery cell according to an embodiment of this utility model;
[0027] Figure 2 This is a side view of the battery cell according to an embodiment of the present invention;
[0028] Figure 3 This is a cross-sectional view of the battery cell according to an embodiment of this utility model.
[0029] In the picture:
[0030] 1. Electrode connection structure;
[0031] 2. Composite foil current collector;
[0032] 3. Composite foil electrode tabs;
[0033] 4. Perforation;
[0034] 5. Bending section;
[0035] 6. First electrode tab; 601. First electrode tab metal layer; 602. Second electrode tab metal layer; 603. First electrode tab substrate layer; 604. Receiving groove;
[0036] 7. Second tab; 701. Third tab metal layer; 702. Fourth tab metal layer; 703. Second tab substrate layer. Detailed Implementation
[0037] To make the technical problems solved, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.
[0038] In the description of this utility model, it should be understood that the terms "longitudinal," "radial," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.
[0039] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal encapsulation of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0040] To address the problem of ineffective electrical conductivity between the metals on both sides of composite foil in related technologies.
[0041] This utility model provides a battery cell.
[0042] The battery cell of this utility model embodiment includes a first polarity electrode, a second polarity electrode, and a separator, wherein at least one of the first polarity electrode and the second polarity electrode includes a tab connection structure 1.
[0043] In other words, the first polarity electrode may include the tab connection structure 1, the second polarity electrode may include the tab connection structure 1, or both the first polarity electrode and the second polarity electrode may include the tab connection structure 1.
[0044] As shown in the figure, the electrode connection structure 1 includes multiple composite foil electrodes 3, each of which includes an electrode substrate layer and two electrode metal layers respectively disposed on both sides of the electrode substrate layer.
[0045] It is understandable that when the first polar electrode includes the tab connection structure 1, the first polar electrode should also include the composite foil current collector 2. The composite foil current collector 2 includes a current collector substrate layer and two current collector metal layers respectively disposed on both sides of the current collector substrate layer. The current collector substrate layer is connected to the tab substrate layer of the composite foil tab 3, and the two current collector metal layers are respectively connected to the corresponding tab metal layers.
[0046] When the second polarity electrode includes the tab connection structure 1, the second polarity electrode should also include the composite foil current collector 2. The composite foil current collector 2 includes a current collector substrate layer and two current collector metal layers respectively disposed on both sides of the current collector substrate layer. The current collector substrate layer is connected to the tab substrate layer of the composite foil tab 3, and the two current collector metal layers are respectively connected to the corresponding tab metal layers.
[0047] When both the first polar electrode and the second polar electrode include the tab connection structure 1, both the first polar electrode and the second polar electrode should also include a composite foil current collector 2. The composite foil current collector 2 includes a current collector substrate layer and two current collector metal layers respectively disposed on both sides of the current collector substrate layer. The current collector substrate layer is connected to the tab substrate layer of the composite foil tab 3, and the two current collector metal layers are respectively connected to the corresponding tab metal layers.
[0048] Both the tab metal layer and the current collector metal layer can be made of copper foil or aluminum foil. It is worth noting that both the tab metal layer and the current collector metal layer should be made of copper foil or aluminum foil.
[0049] The composite foil current collector 2 and the composite foil electrode 3 can be installed as a single unit.
[0050] It is understandable that, in order to integrate the composite foil current collector 2 and the composite foil tab 3, the first polarity electrode and / or the second polarity electrode can be made of composite foil, and multiple composite foil tabs 3 can be cut out on the composite foil using a die-cutting tool.
[0051] Multiple composite foil tabs 3 include a first tab 6 and a second tab 7 alternately arranged in the thickness direction of the cell. The first tab 6 includes a first tab substrate layer 603 and a first tab metal layer 601 and a second tab metal layer 602 disposed on both sides of the first tab substrate layer 603. The second tab 7 includes a second tab substrate layer 703 and a third tab metal layer 701 and a fourth tab metal layer 702 disposed on both sides of the second tab substrate layer 703.
[0052] Among them, the first electrode 6 has a bent part 5, and the second electrode 7 has a perforation 4;
[0053] In the thickness direction of the battery cell, the free end of the bent portion 5 of the first tab 6 located on one side of the second tab 7 passes through the perforation 4 of the second tab 7 and extends to the other side of the second tab 7.
[0054] The second electrode metal layer 602 of the first electrode 6 located on one side of the second electrode 7 is connected to the third electrode metal layer 701 of the second electrode 7, and the first electrode metal layer 601 of the first electrode 6 located on the other side of the second electrode 7 is connected to the fourth electrode metal layer 702 of the second electrode 7.
[0055] The first tab metal layer 601 of the bent portion 5 located on the other side of the second tab 7 is connected to the fourth tab metal layer 702 of the second tab 7;
[0056] The portion of the bent part 5 located on the other side of the second tab 7, the second tab metal layer 602, is connected to the first tab metal layer 601 located on the other side of the first tab 6.
[0057] Thus, the first tab metal layer 601, the second tab metal layer 602, the third tab metal layer 701 and the fourth tab metal layer 702 are interconnected, thereby achieving the effect that the two tab metal layers of the composite foil tab 3 are mutually conductive and all tab metal layers of adjacent composite foil tab 3 are mutually conductive, thereby achieving the effect that the tab metal layers on both sides of the composite foil are mutually conductive.
[0058] In some embodiments, the ratio between the dimension of the perforation 4 in the width direction of the second electrode 7 and the width of the second electrode 7 is 0.1-0.9.
[0059] By setting the ratio between the dimension of the perforation 4 in the width direction of the second electrode 7 and the width of the second electrode 7 to 0.1-0.9, the contact area between the bending portion 5 of the first electrode 6 and the second electrode 7 can be increased, thereby increasing the current-carrying area between the first electrode 6 and the second electrode 7.
[0060] In some embodiments, the ratio between the dimension of the perforation 4 in the length direction of the second electrode 7 and the width of the second electrode 7 is 0.1-0.8.
[0061] Preferably, the ratio between the dimension of the perforation 4 in the length direction of the second electrode 7 and the width of the second electrode 7 is 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7 or 0.8.
[0062] By setting the ratio between the dimension of the perforation 4 in the length direction of the second electrode 7 and the width of the second electrode 7 to 0.1-0.8, it is easier for the bending part 5 of the first electrode 6 to pass through the perforation 4, thus reducing the processing difficulty.
[0063] Preferably, the ratio between the dimension of the perforation 4 in the length direction of the second electrode 7 and the width of the second electrode 7 is 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8 or 0.9.
[0064] In some embodiments, the ratio between the dimension of the bent portion 5 in the width direction of the second electrode lug 7 and the dimension of the perforation 4 in the width direction of the second electrode lug 7 is 0.5-0.9.
[0065] It is understandable that if the ratio between the size of the bent portion 5 in the width direction of the second electrode lug 7 and the size of the perforation 4 in the width direction of the second electrode lug 7 is too small, it will be easier for the bent portion 5 to pass through the perforation 4, but it will reduce the current carrying area between the first electrode lug 6 and the second electrode lug 7; if the ratio between the size of the bent portion 5 in the width direction of the second electrode lug 7 and the size of the perforation 4 in the width direction of the second electrode lug 7 is too large, it will increase the current carrying area between the first electrode lug 6 and the second electrode lug 7, but it will be difficult for the bent portion 5 to pass through the perforation 4.
[0066] The inventors discovered through research that if the ratio between the dimension of the bent portion 5 in the width direction of the second electrode ear 7 and the dimension of the perforation 4 in the width direction of the second electrode ear 7 is 0.5-0.9, it is possible to facilitate the bending portion 5 to pass through the perforation 4 while meeting the requirements of the current carrying area.
[0067] Optionally, the ratio between the dimension of the bent portion 5 in the width direction of the second electrode lug 7 and the dimension of the perforation 4 in the width direction of the second electrode lug 7 is 0.5, 0.6, 0.7, 0.8 or 0.9.
[0068] It is understandable that the ratio between the dimension of the bent portion 5 in the width direction of the second electrode lug 7 and the dimension of the perforation 4 in the width direction of the second electrode lug 7 can be set according to actual needs.
[0069] In some embodiments, the ratio between the dimension between the center of the perforation 4 and the free end of the second electrode plate in the length direction of the second electrode tab 7 and the dimension in the length direction of the second electrode tab 7 is 0.1-0.9.
[0070] It is understandable that the dimension between the center of perforation 4 and the free end of the second electrode is essentially the position of perforation 4 on the second electrode.
[0071] Preferably, the ratio between the dimension between the center of the perforation 4 and the free end of the second pole piece and the dimension in the length direction of the second pole piece 7 is 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8 or 0.9.
[0072] The ratio between the center of the perforation 4 and the free end of the second pole piece and the length of the second pole piece 7 can be set according to actual needs.
[0073] In some embodiments, after the bending portion 5 of the first electrode 6 is bent, a receiving groove 604 is formed on the first electrode 6. The bending portion 5 of the first electrode 6 located on one side of the second electrode 7 is adapted to fit into the receiving groove 604 on the first electrode 6 located on the other side of the second electrode 7, which can avoid the local thickness of the battery cell from increasing due to the setting of the bending portion 5.
[0074] In some embodiments, the battery cell is a wound battery cell, wherein a first polarity electrode, a separator, and a second polarity electrode are stacked and wound along the winding direction to form a wound battery cell.
[0075] In some embodiments, the battery cell is a laminated battery cell, wherein a first polarity electrode, a separator, and a second polarity electrode are stacked to form a laminated battery cell.
[0076] This utility model also provides a battery.
[0077] The battery of this utility model embodiment includes the battery cell described in the above embodiment.
[0078] This utility model embodiment also provides an electrical device. The electrical device of this utility model embodiment includes the battery described in the above embodiment.
[0079] The above-described embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model, and should all be included within the protection scope of this utility model.
Claims
1. A battery cell, characterized in that, The battery includes a first polar electrode, a second polar electrode, and a separator. At least one of the first polar electrode and the second polar electrode includes a tab connection structure (1). The tab connection structure (1) includes a plurality of composite foil tabs (3). The plurality of composite foil tabs (3) include a first tab (6) and a second tab (7) alternately arranged in the thickness direction of the battery cell. The first electrode (6) includes a first electrode substrate layer (603) and a first electrode metal layer (601) and a second electrode metal layer (602) disposed on both sides of the first electrode substrate layer (603). The second electrode (7) includes a second electrode substrate layer (703) and a third electrode metal layer (701) and a fourth electrode metal layer (702) disposed on both sides of the second electrode substrate layer (703). The first electrode (6) has a bent portion (5), and the second electrode (7) has a perforation (4); In the thickness direction of the battery cell, the free end of the bent portion (5) of the first tab (6) located on one side of the second tab (7) passes through the perforation (4) of the second tab (7) and extends to the other side of the second tab (7); The second electrode metal layer (602) of the first electrode (6) located on one side of the second electrode (7) is connected to the third electrode metal layer (701) of the second electrode (7), and the first electrode metal layer (601) of the first electrode (6) located on the other side of the second electrode (7) is connected to the fourth electrode metal layer (702) of the second electrode (7). The first electrode metal layer (601) of the portion of the bent part (5) located on the other side of the second electrode (7) is connected to the fourth electrode metal layer (702) of the second electrode (7); The second electrode metal layer (602) of the bent portion (5) located on the other side of the second electrode (7) is connected to the first electrode metal layer (601) of the first electrode (6) located on the other side of the second electrode (7).
2. The battery cell according to claim 1, characterized in that, The ratio between the dimension of the perforation (4) in the width direction of the second electrode (7) and the width of the second electrode (7) is 0.1-0.
9.
3. The battery cell according to claim 2, characterized in that, The ratio between the dimension of the perforation (4) in the length direction of the second electrode (7) and the width of the second electrode (7) is 0.1-0.
8.
4. The battery cell according to claim 1, characterized in that, The ratio between the dimension of the bent portion (5) in the width direction of the second tab (7) and the dimension of the perforation (4) in the width direction of the second tab (7) is 0.5-0.
9.
5. The battery cell according to claim 1, characterized in that, In the length direction of the second electrode tab (7), the ratio between the center of the perforation (4) and one end of the second electrode in its length direction and the length direction of the second electrode tab (7) is 0.1-0.
9.
6. The battery cell according to claim 4, characterized in that, After the bending portion (5) of the first electrode (6) is bent, a receiving groove (604) is formed on the first electrode (6). The bending portion (5) of the first electrode (6) located on one side of the second electrode (7) is adapted to fit into the receiving groove (604) on the first electrode (6) located on the other side of the second electrode (7).
7. The battery cell according to claim 1, characterized in that, The battery cell is a wound battery cell, wherein the first polarity electrode, the separator, and the second polarity electrode are stacked and wound along the winding direction to form the wound battery cell.
8. The battery cell according to claim 1, characterized in that, The battery cell is a laminated battery cell, wherein the first polarity electrode, the separator, and the second polarity electrode are stacked to form the laminated battery cell.
9. A battery, characterized in that, The battery comprises the cell according to any one of claims 1-8.
10. An electrical appliance, characterized in that, The electrical device includes the battery as described in claim 9.