Composite foil tab, battery cell, and battery

Abstract

The utility model provides a kind of composite foil tab, battery and electric core.The utility model embodiment's composite foil tab includes substrate layer and respectively being located in the first conductive layer and the second conductive layer of substrate layer two sides;Composite foil tab is equipped with torsion line, first cutting line and second cutting line;One end of first cutting line is located in one end of torsion line, the other end of first cutting line is located in the one side outer edge of composite foil tab;One end of second cutting line is located in the other end of torsion line, the other end of second cutting line is located in the other side outer edge of composite foil tab;First cutting line, second cutting line and torsion line will be divided into fixed part and torsion part for composite foil tab, fixed part has the fixed end for connecting composite foil current collector;Torsion part is folded 180 ° along torsion direction around torsion line, can make that first conductive layer and second conductive layer can form effective electrical connection between when composite foil tab is stacked.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a composite foil tab, a battery cell, and a battery. 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 foil current collectors are often used instead of traditional metal foil current collectors. Composite foil current collectors have two main advantages: firstly, they have a lower areal density, reducing the weight of the current collector and thus increasing the battery's energy density; secondly, due to the high ductility of polymer materials, when a lithium-ion battery is impacted by a foreign object, the polymer material can wrap around the fracture surface, preventing the fracture from puncturing the separator and causing a short circuit, reducing the risk of thermal runaway, and improving the safety performance of the lithium-ion battery.

[0004] However, due to the low conductivity of polymer materials, effective electrical conduction cannot occur between the conductive layers on both sides of the polymer material.

[0005] Therefore, the composite foil tabs in related technologies suffer from the problem that effective electrical conduction cannot occur between the conductive layers on both sides. Utility Model Content

[0006] This utility model provides a composite foil tab to solve the problem in related technologies where effective conductivity cannot be achieved between the conductive layers on both sides of the composite foil tab.

[0007] The composite foil tab of this utility model includes a substrate layer and a first conductive layer and a second conductive layer respectively disposed on both sides of the substrate layer;

[0008] The composite foil tabs are provided with a twist line, a first cutting line, and a second cutting line;

[0009] One end of the first cutting line is located at one end of the twisted line, and the other end of the first cutting line is located at the outer edge of one side of the composite foil tab.

[0010] One end of the second cutting line is located at the other end of the twisted line, and the other end of the second cutting line is located at the outer edge of the other side of the composite foil tab;

[0011] The first cutting line, the second cutting line, and the twisting line divide the composite foil tab into a fixed part and a twisting part. The fixed part has a fixed end for connecting the composite foil current collector.

[0012] The twisted portion is folded 180° around the twist line along the twist direction.

[0013] The above configuration allows the first and second conductive layers of the composite foil tabs to be located on the same side. When multiple composite foil tabs are overlapped, the first and second conductive layers of the composite foil tabs can be electrically connected, that is, an effective electrical connection can be formed between the first and second conductive layers of the composite foil tabs.

[0014] For example, in adjacent composite foil tabs, the first conductive layer of the twisted portion of one composite foil tab is electrically connected to the first conductive layer of the fixed portion and the second conductive layer of the twisted portion of the other composite foil tab, thereby achieving the effect of electrically connecting the first and second conductive layers of the other composite foil tab.

[0015] The first conductive layer of the fixing part of one of the composite foil tabs is electrically connected to the first conductive layer of the twisting part and the second conductive layer of the fixing part of one of the composite foil tabs, thereby achieving the effect of electrically connecting the first conductive layer and the second conductive layer in one of the composite foil tabs.

[0016] Therefore, by providing a twisting portion, the composite foil electrode tabs of this utility model embodiment enable an effective electrical connection to be formed between the first conductive layer and the second conductive layer when the composite foil electrode tabs are stacked.

[0017] In some embodiments, one end of the first cutting line and one end of the second cutting line are sequentially spaced apart in a direction away from the fixed end;

[0018] Along the length of the composite foil tab,

[0019] The distance between the connection point of one end of the first cutting line and the twisted line and the free end of the composite foil tab is 0.3-0.7 times the length of the composite foil tab; and / or

[0020] The distance between the connection point of one end of the second cutting line and the twisted line and the free end of the composite foil tab is 0.3-0.7 times the distance between the connection point of one end of the first cutting line and the twisted line and the free end of the composite foil tab.

[0021] In some embodiments, the angle A between the twisted line and the length direction of the composite foil tab satisfies 0°≤A<90°.

[0022] In some embodiments, the angle A between the twisted line and the length direction of the composite foil tab is 0°.

[0023] In some embodiments, in the width direction of the composite foil tab, the distance between the twist line and the side edge in the width direction of the composite foil tab is 0.3-0.7 times the width of the composite foil tab.

[0024] In some embodiments, the twisted line is centered in the width direction of the composite foil tab.

[0025] In some embodiments, the first cutting line is a straight groove or the first cutting line is an arc groove, and / or

[0026] The second cutting line is either a straight groove or an arc groove.

[0027] In some embodiments, the first cutting line is a straight groove, which extends in the width direction of the composite foil tab; the second cutting line is a straight groove, which extends in the width direction of the composite foil tab.

[0028] This utility model also provides a battery cell.

[0029] The battery cell of this utility model embodiment includes a composite foil current collector and a plurality of composite foil tabs as described in the above embodiment, wherein the fixed end of the composite foil tab is connected to the composite foil current collector;

[0030] Multiple composite foil tabs are stacked together. In two adjacent composite foil tabs, the first conductive layer of the fixing portion of one composite foil tab is connected to the second conductive layer of the fixing portion of the other composite foil tab; the second conductive layer of the twisted portion of one composite foil tab is connected to the second conductive layer of the fixing portion of the other composite foil tab, and connected to the first conductive layer of the twisted portion of the other composite foil tab.

[0031] This utility model also provides a battery.

[0032] The battery of this embodiment includes the battery cell described in the above embodiment.

[0033] By providing the battery cell described in the above embodiments, the battery of this utility model can form an effective electrical connection between the first conductive layer and the second conductive layer of the composite foil electrode tab. Attached Figure Description

[0034] 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.

[0035] Figure 1 This is a cross-sectional view of the composite foil electrode tab of this utility model embodiment;

[0036] Figure 2 This is a schematic diagram of the composite foil electrode tab of this utility model embodiment;

[0037] Figure 3 This is a schematic diagram of the composite foil electrode tab after folding according to an embodiment of the present invention;

[0038] Figure 4 This is one of the structural schematic diagrams of the composite foil electrode tab of another embodiment of this utility model;

[0039] Figure 5 This is a second schematic diagram of the structure of the composite foil electrode tab in another embodiment of this utility model;

[0040] Figure 6 This is the third schematic diagram of the composite foil electrode tab of another embodiment of this utility model;

[0041] Figure 7 This is the fourth schematic diagram of the composite foil electrode tab of another embodiment of this utility model;

[0042] Figure 8 This is a schematic diagram of the structure of the battery cell according to an embodiment of this utility model;

[0043] Figure 9 This is a schematic diagram of the stacked battery cells according to an embodiment of the present invention.

[0044] In the picture:

[0045] 100. Battery cells;

[0046] 1. Composite foil tabs;

[0047] 101. Twist line; 102. First cutting line; 103. Second cutting line; 104. Twist portion; 105. Fixing portion; 1051. Fixing end;

[0048] 2. First conductive layer;

[0049] 3. Second conductive layer;

[0050] 4. Substrate layer;

[0051] 5. Composite foil current collector. Detailed Implementation

[0052] 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.

[0053] 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.

[0054] 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.

[0055] In order to solve the problem that the conductive layers on both sides of the composite foil tab 1 cannot conduct electricity effectively.

[0056] This utility model provides a composite foil electrode tab 1.

[0057] The composite foil tab 1 of this utility model embodiment includes a substrate layer 4 and a first conductive layer 2 and a second conductive layer 3 respectively disposed on both sides of the substrate layer 4.

[0058] The composite foil tab 1 is provided with a twist line 101, a first cutting line 102, and a second cutting line 103;

[0059] One end of the first cutting line 102 is located at one end of the twisted line 101, and the other end of the first cutting line 102 is located at the outer edge of one side of the composite foil tab 1;

[0060] One end of the second cutting line 103 is located at the other end of the twisted line 101, and the other end of the second cutting line 103 is located at the outer edge of the other side of the composite foil tab 1;

[0061] The first cutting line 102, the second cutting line 103 and the twisting line 101 divide the composite foil tab 1 into a fixed part 105 and a twisting part 104.

[0062] The twisting part 104 is folded 180° around the twisting line 101 in the twisting direction, and the twisting part 104 and the partial fixing part 105 are stacked to form a stacked part.

[0063] The above arrangement allows the first conductive layer 2 and the second conductive layer 3 of the composite foil tab 1 to be located on the same side. When multiple composite foil tabs 1 are overlapped, the first conductive layer 2 and the second conductive layer 3 of the composite foil tab 1 can be electrically connected, that is, an effective electrical connection can be formed between the first conductive layer 2 and the second conductive layer 3 of the composite foil tab 1.

[0064] For example, in adjacent composite foil tabs 1, the first conductive layer 2 of the twisted portion 104 of one composite foil tab 1 is electrically connected to the first conductive layer 2 of the fixed portion 105 and the second conductive layer 3 of the twisted portion 104 of the other composite foil tab 1, which can achieve the effect of electrically connecting the first conductive layer 2 and the second conductive layer 3 of the other composite foil tab 1.

[0065] The first conductive layer 2 of the fixing part 105 of another composite foil tab 1 is electrically connected to the first conductive layer 2 of the twisting part 104 and the second conductive layer 3 of the fixing part 105 of one of the composite foil tabs 1, thereby achieving the effect of electrically connecting the first conductive layer 2 and the second conductive layer 3 in one of the composite foil tabs 1.

[0066] Therefore, by providing the twisting part 104, the composite foil tab 1 of this utility model embodiment can enable an effective electrical connection to be formed between the first conductive layer 2 and the second conductive layer 3 when the composite foil tab 1 is stacked.

[0067] In some embodiments, one end of the first cutting line 102 and one end of the second cutting line 103 are sequentially spaced apart in a direction away from the fixed end.

[0068] Along the length direction of the composite foil tab 1

[0069] The distance between the connection point of one end of the first cutting line and the twisted line 101 and the free end of the composite foil tab 1 is 0.3-0.7 of the length of the composite foil tab 1; and / or

[0070] The distance between the connection point of one end of the second cutting line and the twist line 101 and the free end of the composite foil tab 1 is 0.3-0.7 times the distance between the connection point of one end of the first cutting line and the twist line 101 and the free end of the composite foil tab 1.

[0071] In some embodiments, the angle A between the twisted line 101 and the longitudinal direction of the composite foil tab 1 satisfies 0°≤A<90°.

[0072] Preferably, the angle A between the twisted line 101 and the length direction of the composite foil tab 1 is 0°.

[0073] It is understandable that when the angle A between the twisted line 101 and the length direction of the composite foil tab 1 is 0°, the twisted line 101 extends along the length direction of the composite foil tab 1.

[0074] Furthermore, in the width direction of the composite foil tab 1, the distance between the twist line 101 and the side edge in the width direction of the composite foil tab 1 is 0.3-0.7 of the width of the composite foil tab 1.

[0075] Furthermore, the twist line 101 is centered in the width direction of the composite foil tab 1.

[0076] By setting the angle A between the twist line 101 and the length direction of the composite foil tab 1 to 0 degrees, and centering the twist line 101 in the width direction of the composite foil tab 1, the edge of the twisted part 104 will not exceed the edge of the composite foil tab 1 after twisting, which facilitates the subsequent assembly of the battery cell into a battery.

[0077] In some embodiments, the first cutting line 102 is a straight groove or an arc groove, and / or the second cutting line 103 is a straight groove or an arc groove.

[0078] For example, such as Figure 2 , Figure 4 and Figure 5 The first cutting line 102 is a straight groove, and the second cutting line 103 is a straight groove;

[0079] For example, such as Figure 7 As shown, the first cutting line 102 is a straight groove, and the second cutting line 103 is an arc groove;

[0080] For example, such as Figure 6 As shown, the first cutting line 102 is an arc groove, and the second cutting line 103 is a straight groove;

[0081] For example, the first cutting line 102 is an arc groove, and the second cutting line 103 is an arc groove.

[0082] In some embodiments, the first cutting line 102 is a straight groove, and the first cutting line 102 extends in the width direction of the composite foil tab 1; the second cutting line 103 is a straight groove, and the second cutting line 103 extends in the width direction of the composite foil tab 1.

[0083] This utility model also provides a battery cell.

[0084] The battery cell 100 of this utility model embodiment includes a composite foil current collector 5 and a plurality of composite foil tabs 1 as described in the above embodiment. The fixed end 1051 of the composite foil tab 1 is connected to the composite foil current collector 5.

[0085] Multiple composite foil tabs 1 are stacked. In two adjacent composite foil tabs 1, the first conductive layer of the fixing part of one composite foil tab 1 is connected to the second conductive layer of the fixing part of the other composite foil tab 1; the second conductive layer of the twisted part of one composite foil tab 1 is connected to the second conductive layer of the fixing part of the other composite foil tab 1, and connected to the first conductive layer of the twisted part of the other composite foil tab 1, so that the first conductive layer and the second conductive layer of the other composite foil tab 1 are connected.

[0086] Therefore, an effective electrical connection can be formed between the first conductive layer 2 and the second conductive layer 3 of the composite foil tab 1 of the battery cell in this embodiment of the present invention.

[0087] This utility model also provides a battery.

[0088] The battery of this embodiment includes the battery cell described in the above embodiment.

[0089] By setting the battery cell described in the above embodiment, an effective electrical connection can be formed between the first conductive layer 2 and the second conductive layer 3 of the composite foil tab 1 of the battery in this embodiment.

[0090] The above 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 composite foil electrode tab, characterized in that, It includes a substrate layer and a first conductive layer and a second conductive layer respectively disposed on both sides of the substrate layer; The composite foil tabs are provided with a twist line, a first cutting line, and a second cutting line; One end of the first cutting line is located at one end of the twisted line, and the other end of the first cutting line is located at the outer edge of one side of the composite foil tab. One end of the second cutting line is located at the other end of the twisted line, and the other end of the second cutting line is located at the other outer edge of the composite foil tab. The first cutting line, the second cutting line, and the twisting line divide the composite foil tab into a fixed part and a twisting part. The fixed part has a fixed end for connecting the composite foil current collector. The twisted portion is folded 180° around the twist line along the twist direction.

2. The composite foil tab according to claim 1, characterized in that, One end of the first cutting line and one end of the second cutting line are arranged at intervals in a direction away from the fixed end; Along the length of the composite foil tab, The distance between the connection point of one end of the first cutting line and the twisted line and the free end of the composite foil tab is 0.3-0.7 times the length of the composite foil tab; and / or The distance between the connection point of one end of the second cutting line and the twisted line and the free end of the composite foil tab is 0.3-0.7 times the distance between the connection point of one end of the first cutting line and the twisted line and the free end of the composite foil tab.

3. The composite foil tab according to claim 1, characterized in that, The angle A between the twist line and the length direction of the composite foil tab satisfies 0°≤A<90°.

4. The composite foil tab according to claim 3, characterized in that, The angle A between the twist line and the length direction of the composite foil tab is 0°.

5. The composite foil tab according to claim 4, characterized in that, In the width direction of the composite foil tab, the distance between the twist line and the side edge in the width direction of the composite foil tab is 0.3-0.7 times the width of the composite foil tab.

6. The composite foil tab according to claim 5, characterized in that, The twist line is centered in the width direction of the composite foil tab.

7. The composite foil tab according to claim 1, characterized in that, The first cutting line is a straight groove or the first cutting line is an arc groove, and / or The second cutting line is either a straight groove or an arc groove.

8. The composite foil tab according to claim 1, characterized in that, The first cutting line is a straight groove, which extends in the width direction of the composite foil tab; the second cutting line is a straight groove, which extends in the width direction of the composite foil tab.

9. A battery cell, characterized in that, It includes a composite foil current collector and a plurality of composite foil tabs as described in any one of claims 1-8, wherein the fixed end of the composite foil tab is connected to the composite foil current collector; Multiple composite foil tabs are stacked together. In two adjacent composite foil tabs, the first conductive layer of the fixing portion of one composite foil tab is connected to the second conductive layer of the fixing portion of the other composite foil tab; the second conductive layer of the twisted portion of one composite foil tab is connected to the second conductive layer of the fixing portion of the other composite foil tab, and connected to the first conductive layer of the twisted portion of the other composite foil tab.

10. A battery, characterized in that, Including the battery cell as described in claim 9.

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