Pole piece structure, battery and electric device
By spraying a conductive layer onto the electrode structure, the impact of overlapping multiple tabs on the cell thickness was resolved, thereby improving battery performance and reducing manufacturing difficulty and cost.
Patent Information
- Application Number
- CN202423012204.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-06
- Publication Date
- 2026-01-13
- Estimated Expiration
- 2034-12-06
AI Technical Summary
The existing composite current collectors with overlapping tabs can affect the cell thickness, leading to a decrease in battery performance.
An optimized electrode structure is adopted, and the electrical connection between the upper and lower conductive layers is achieved by spraying a conductive layer in the first and second directions of the composite current collector, avoiding the overlap of multiple tabs. The conductive layer can be formed by low-pressure cold spraying, magnetron sputtering or electron beam evaporation.
This reduces the difficulty of electrode preparation, improves the assembly efficiency of battery tabs, reduces equipment energy consumption and labor costs, and improves battery quality.
Smart Images
Figure CN223797340U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the technical field of battery manufacturing, specifically relating to an electrode structure, a battery, and an electrical device. Background Technology
[0002] Today, lithium-ion batteries, as a new type of rechargeable battery, have advantages such as high energy density, high operating voltage, light weight, small size, long cycle life, good safety, and environmental friendliness. They have broad application prospects in portable electrical appliances, power tools, large-scale energy storage, and electric transportation power supplies.
[0003] Composite current collectors typically employ a three-layer sandwich structure of metal-polymer-metal, but this results in high resistance.
[0004] In the process of developing this utility model, the inventors discovered at least the following problems in the prior art.
[0005] Existing composite current collectors typically use multiple tabs to conduct between upper and lower layers, but overlapping multiple tabs can affect the cell thickness. Utility Model Content
[0006] One of the objectives of this invention is to address the shortcomings of existing technologies by providing an electrode structure that optimizes the electrode structure to solve the problem of overlapping tabs affecting cell thickness, thereby improving battery quality.
[0007] To achieve the above objectives, the present invention adopts the following technical solution:
[0008] An electrode structure includes a composite current collector and an active material layer. The composite current collector includes an intermediate layer and a conductive layer. The conductive layer is disposed on the surface of the intermediate layer. The active material layer is disposed on the surface of the conductive layer away from the intermediate layer. The composite current collector has a first direction and a second direction perpendicular to the first direction. The composite current collector has a first end and a second end opposite to each other in the first direction. The first end and / or the second end is covered with a conductive layer. The two sides of the composite current collector in the second direction are electrically connected through the conductive layer.
[0009] In some possible implementations, at least a portion of the conductive layer is sprayed onto one side of the composite current collector in the second direction, the area of the portion of the conductive layer being S, and the area of the composite current collector on one side in the second direction being S, satisfying the relationship: S1 / S2 = 0.6~1; or S1 / S2 = 0.9.
[0010] In some possible implementations, the thickness of the conductive layer sprayed along the second direction is 0.1–2 μm; or
[0011] The thickness of the conductive layer sprayed along the second direction is 1 μm.
[0012] In some possible implementations, the conductive layer is a metal layer, and the conductive layer is one of aluminum, copper, nickel, titanium, silver, or a nickel-copper alloy. The peel strength between the conductive layer and the composite current collector is 200-1000 N / m; or
[0013] The peel strength between the conductive layer and the composite current collector is 500 N / m.
[0014] In some possible implementations, the conductive layer is sprayed onto the peripheral and end sides of the first end; and / or
[0015] The conductive layer is sprayed onto the peripheral and end sides of the second end.
[0016] In some possible embodiments, the interlayer is polypropylene or polyethylene terephthalate, and the thickness of the interlayer is 1 μm to 10 μm; or
[0017] The thickness of the intermediate layer is 4 μm.
[0018] In some possible implementations, the conductive layer is a metal layer, the metal layer being aluminum or copper, and the thickness of the conductive layer is 0.5 μm to 8 μm; or
[0019] The thickness of the conductive layer is 1 μm.
[0020] In some possible implementations, the active material layer is a positive electrode active material or a negative electrode active material, and the thickness of the active material layer is 10 to 200 μm.
[0021] The second objective of this utility model is to provide a battery that includes the above-mentioned electrode structure.
[0022] The third objective of this utility model is to provide an electrical device, including the aforementioned battery.
[0023] One of the above technical solutions has the following beneficial effects.
[0024] This application optimizes the electrode structure by spraying a conductive layer onto the electrode. This conductive layer covers the first and second ends of the composite current collector, achieving conductivity between the upper and lower conductive layers of the composite current collector and avoiding the impact of overlapping tabs on cell thickness found in existing multi-tab systems. Furthermore, the conductive layer can be formed at the first and second ends, which are opposite each other in the first direction, using low-pressure cold spraying, magnetron sputtering, or electron beam evaporation, which helps reduce the difficulty of electrode fabrication. In addition, spraying offers advantages over welding, such as simpler operation and easier assembly, thereby improving the assembly efficiency of battery tabs and reducing equipment energy consumption and labor costs. Attached Figure Description
[0025] The features, advantages and technical effects of exemplary embodiments of the present invention will now be described with reference to the accompanying drawings.
[0026] Figure 1 This is a schematic diagram of the structure of this utility model.
[0027] The reference numerals in the attached figures are explained as follows:
[0028] 1-Intermediate layer;
[0029] 2-Conductive layer;
[0030] 3-Active substance layer;
[0031] 4-Conducting layer;
[0032] X - First direction; Y - Second direction. Detailed Implementation
[0033] If certain terms are used in the specification and claims to refer to specific components, those skilled in the art will understand that hardware manufacturers may use different names to refer to the same component. This specification and claims do not distinguish components based on differences in name, but rather on differences in function. The term "comprising" as used throughout the specification and claims is an open-ended term and should be interpreted as "comprising but not limited to." "Approximately" means that within an acceptable margin of error, those skilled in the art can solve the technical problem and substantially achieve the technical effect within a certain margin of error.
[0034] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be interpreted as indicating or implying relative importance.
[0035] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., 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 connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0036] The present invention will be further described in detail below with reference to the accompanying drawings, but this is not intended to limit the present invention.
[0037] like Figure 1As shown, an embodiment provides an electrode structure including a composite current collector and an active material layer 3. The composite current collector includes an intermediate layer 1 and a conductive layer 2. The conductive layer 2 is disposed on the surface of the intermediate layer 1. The active material layer 3 is disposed on the surface of the conductive layer 2 away from the intermediate layer 1. The intermediate layer 1 has conductive layers 2 disposed on both sides in the thickness direction. The two surfaces of the conductive layer 2 away from the intermediate layer 1 are coated with the active material layer 3. In some embodiments, the surface of the conductive layer 2 away from the intermediate layer 1 is coated with the active material layer 3, while the other side is not coated with the active material layer 3. This can be adjusted according to the actual battery structure.
[0038] In this embodiment, the composite current collector has a first direction X and a second direction Y perpendicular to the first direction X. The first direction X is parallel to the length direction of the composite current collector, meaning that conductive layers 2 are sprayed onto both sides after the electrode is slit. Spraying conductive layers 2 helps to improve the conductivity of the composite current collector electrode. In other embodiments, the first direction X may also be parallel to the width direction of the composite current collector; this is not a limitation. The second direction Y is parallel to the thickness direction of the composite current collector and is perpendicular to the first direction X.
[0039] The composite current collector has a first end and a second end opposite to each other in the first direction X. The conductive layer 4 can be disposed at the first end and the second end, which helps to improve the overall conductivity of the composite current collector. In some embodiments, the conductive layer 4 can be disposed only at the first end or the second end, which is sufficient to satisfy the electrical connection between the upper and lower conductive layers 2 of the composite current collector.
[0040] In this embodiment, the first end and / or the second end are covered with a conductive layer 4, and the two sides of the composite current collector in the second direction Y are electrically connected through the conductive layer 4. Thus, the upper and lower conductive layers 2 of the composite current collector can be made conductive.
[0041] Compared to existing electrode sheets that use multiple tabs for upper and lower layer conduction, this application optimizes the electrode structure by spraying a conductive layer 4 onto the electrode. This conductive layer 4 covers the first and second ends of the composite current collector, achieving conduction between the upper and lower conductive layers 2 of the composite current collector and avoiding the impact of overlapping tabs on the cell thickness. Furthermore, the conductive layer 4 can be formed at the first and second ends opposite each other in the first direction X using low-pressure cold spraying, magnetron sputtering, or electron beam evaporation, which helps reduce the difficulty of electrode fabrication. In addition, spraying has advantages over welding, such as simple operation and convenient assembly, thereby improving the assembly efficiency of the battery tabs and reducing equipment energy consumption and labor costs.
[0042] In this embodiment, at least a portion of the conductive layer 4 is sprayed onto one side of the composite current collector in the second direction Y, i.e., the conductive layer 4 is sprayed onto one side in the thickness direction of the composite current collector. The area of this portion of the conductive layer 4 is S1, and the area of the composite current collector on the side in the second direction Y is S2, satisfying the relationship: S1 / S2 = 0.6~1. This limits the sprayed area of the conductive layer 4 to 60%~100% of the side surface area of the electrode, thereby ensuring effective connection between the conductive layer 4 and the composite current collector, maximizing the contact area between the conductive layer 4 and the composite current collector, and helping to reduce internal resistance. Preferably, the conductive layer 4 is sprayed with a metallic material, but it can also be other non-metallic materials with conductive properties.
[0043] For example, in some embodiments, S1 / S2 can be set to 0.6, 0.7, 0.8, 0.9 or 1, or any other value from 0.6 to 1.
[0044] Preferably, in other embodiments, the area of the composite current collector on one side in the second direction Y is S2, satisfying the relationship: S1 / S2 = 0.9. That is, the area of the conductive layer 4 is limited to 90% of the side area of the electrode, which ensures effective connection between the conductive layer 4 and the composite current collector while reducing the coating cost of the conductive layer 4.
[0045] In some embodiments, the thickness of the conductive layer 4 sprayed along the second direction Y is 0.1 to 2 μm. That is, the thickness of the conductive layer 4 sprayed on one side of the composite current collector in the thickness direction meets the above range, which can ensure effective connection between the conductive layer 4 and the composite current collector and help reduce internal resistance.
[0046] For example, in some embodiments, the thickness of the conductive layer 4 sprayed along the second direction Y can be set to 0.1μm, 0.2μm, 0.3μm, 0.4μm, 0.5μm, 0.6μm, 0.7μm, 0.8μm, 0.9μm, 1μm, etc., or can be set to any other value from 0.1 to 2μm.
[0047] Preferably, in other embodiments, the thickness of the conductive layer 4 sprayed along the second direction Y is 1 μm. This ensures effective connection between the conductive layer 4 and the composite current collector while reducing the spraying cost of the conductive layer 4.
[0048] In some embodiments, the conductive layer 4 is a metal layer, and the conductive layer 4 is one of aluminum, copper, nickel, titanium, silver, and nickel-copper alloy. In other embodiments, the conductive layer 4 is selected from at least one of aluminum, copper, nickel, titanium, silver, and nickel-copper alloy. It can be formed on the composite current collector by at least one of low-pressure cold spraying, magnetron sputtering, and electron beam evaporation.
[0049] In this embodiment, the peel strength between the conductive layer 4 and the composite current collector is 200-1000 N / m. This ensures the connection strength between the conductive layer 4 and the composite current collector, reducing the probability of the conductive layer 4 detaching during use.
[0050] For example, in some embodiments, the peel strength between the conductive layer 4 and the composite current collector can be set to 200 N / m, 300 N / m, 400 N / m, 500 N / m, 600 N / m, 700 N / m, 800 N / m, 900 N / m, 1000 N / m, etc., or can be set to any other value in the range of 200-1000 N / m.
[0051] Preferably, in other embodiments, the peel strength between the conductive layer 4 and the composite current collector is 500 N / m. This ensures the connection strength between the conductive layer 4 and the composite current collector while reducing the cost of the conductive layer 4.
[0052] In some embodiments, a conductive layer 4 is sprayed onto the peripheral and end sides of the first end. This can increase the electrical contact area between the composite current collector and the conductive layer 4, and reduce the internal resistance.
[0053] Preferably, in other embodiments, the conductive layer 4 is sprayed on the peripheral and end sides of the first end, and simultaneously on the peripheral and end sides of the second end. This can further increase the electrical contact area between the composite current collector and the conductive layer 4, and reduce the internal resistance. The peripheral side of the first or second end includes both sides of the composite current collector in the thickness direction and both sides of the composite current collector in the width direction, while the end side of the first or second end includes both sides of the composite current collector in the length direction.
[0054] In some embodiments, the intermediate layer 1 is polypropylene or polyethylene terephthalate, and the thickness of the intermediate layer 1 is 1 μm to 10 μm. This avoids the intermediate layer 1 being too thick, which would affect the overall thickness of the composite current collector.
[0055] For example, in some embodiments, the thickness of the intermediate layer 1 can be set to 1μm, 2μm, 3μm, 4μm, 5μm, 6μm, 7μm, 8μm, 9μm, 10μm, etc., or can be set to any other value from 1μm to 10μm.
[0056] Preferably, in some other embodiments, the thickness of the intermediate layer 1 is 4 μm. This avoids making the intermediate layer 1 too thick while reducing its cost.
[0057] In some embodiments, the conductive layer 2 is preferably a metal layer, preferably aluminum or copper. The conductive layer 2 can also be other conductive metallic or non-metallic materials; there are no limitations on this. The thickness of the conductive layer 2 is 0.5 μm to 8 μm. This ensures that the thickness of the composite current collector is within a preset range, reducing internal resistance.
[0058] For example, in some embodiments, the thickness of the conductive layer 2 is 0.5μm, 1.5μm, 2.5μm, 3.5μm, 4.5μm, 5.5μm, 6.5μm, 7.5μm, 8μm, etc., and can also be set to any other value from 0.5μm to 8μm.
[0059] Preferably, in some other embodiments, the thickness of the conductive layer 2 is 1 μm. This ensures that the thickness of the composite current collector is within a preset range while reducing the cost of the conductive layer 2.
[0060] In some embodiments, the active material layer 3 is a positive or negative electrode active material, and the composite current collector can be applied to either the positive or negative electrode sheet of the battery. The thickness of the active material layer 3 is 10–200 μm. This ensures the energy density of the composite current collector while reducing internal resistance.
[0061] For example, in some embodiments, the thickness of the active material layer 3 can be set to 10μm, 20μm, 30μm, 40μm, 50μm, 60μm, 70μm, 80μm, 90μm, 100μm, 110μm, 120μm, 130μm, 140μm, 150μm, 160μm, 170μm, 180μm, 190μm, 200μm, etc., or can be set to any other value from 10 to 200μm.
[0062] Battery
[0063] The battery includes a first electrode, a separator, and a second electrode. The first electrode, the separator, and the second electrode are sequentially wound to form a bare cell. At least one of the first electrode and the second electrode adopts the above-described structure.
[0064] The battery is packaged in an aluminum-plastic film or a metal shell, or other materials such as packaging shells or bags; there are no restrictions on this.
[0065] A battery may include at least two electrodes stacked on top of each other with opposite polarities, which are the positive and negative electrodes of the battery, respectively. To prevent short circuits between the positive and negative electrodes, a separator is provided between each pair of adjacent electrodes, and the electrodes with opposite polarities are electrically isolated by the separator.
[0066] To prevent short circuits between the positive and negative electrodes, electrodes with opposite polarities are electrically isolated by a diaphragm. The first and second electrodes have opposite polarities and are stacked on top of each other.
[0067] The first electrode can be a positive electrode and the second electrode can be a negative electrode; or, the first electrode can be a negative electrode and the second electrode can be a positive electrode, without any restrictions.
[0068] Electrical appliances
[0069] Batteries incorporating the electrode structure of this invention can also be used in electrical devices, including automobiles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools. Automobiles can be gasoline-powered, natural gas-powered, or new energy vehicles; new energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles. Spacecraft include airplanes, rockets, space shuttles, and spacecraft. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers. This application does not impose any special limitations on the aforementioned electrical devices.
[0070] Based on the disclosure and teachings of the above specification, those skilled in the art can make changes and modifications to the above embodiments. Therefore, this utility model is not limited to the specific embodiments described above, and any obvious improvements, substitutions, or modifications made by those skilled in the art based on this utility model are within the protection scope of this utility model. Furthermore, although some specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any limitation on this utility model.
Claims
1. An electrode structure, characterized in that, It includes a composite current collector and an active material layer (3), wherein the composite current collector includes an intermediate layer (1) and a conductive layer (2); The conductive layer (2) is disposed on the surface of the intermediate layer (1); The active material layer (3) is disposed on the surface of the conductive layer (2) away from the intermediate layer (1); The composite current collector has a first direction (X) and a second direction (Y) perpendicular to the first direction (X). The composite current collector has a first end and a second end opposite to each other in the first direction (X). The first end and / or the second end is covered with a conductive layer (4). The two sides of the composite current collector in the second direction (Y) are electrically connected through the conductive layer (4).
2. The electrode structure as described in claim 1, characterized in that: At least a portion of the conductive layer (4) is sprayed onto one side of the composite current collector in the second direction (Y), the area of the portion of the conductive layer (4) is S1, and the area of the composite current collector on the second direction (Y) is S2, satisfying the relationship: S1 / S2 = 0.6~1; or S1 / S2 = 0.
9.
3. The electrode structure as described in claim 2, characterized in that: The thickness of the conductive layer (4) sprayed along the second direction (Y) is 0.1–2 μm; or The thickness of the conductive layer (4) sprayed along the second direction (Y) is 1 μm.
4. The electrode structure as described in claim 3, characterized in that: The conductive layer (4) is a metal layer, and the conductive layer (4) is one of aluminum, copper, nickel, titanium, silver, and nickel-copper alloy. The peel strength between the conductive layer (4) and the composite current collector is 200-1000 N / m; or The peel strength between the conductive layer (4) and the composite current collector is 500 N / m.
5. An electrode structure as described in any one of claims 1-4, characterized in that: The conductive layer (4) is sprayed onto the peripheral and end sides of the first end; and / or The conductive layer (4) is sprayed on the peripheral and end sides of the second end.
6. An electrode structure as described in any one of claims 1-4, characterized in that: The intermediate layer (1) is polypropylene or polyethylene terephthalate, and the thickness of the intermediate layer (1) is 1 μm to 10 μm; or The thickness of the intermediate layer (1) is 4 μm.
7. An electrode structure as described in any one of claims 1-4, characterized in that: The conductive layer (2) is a metal layer, which is aluminum or copper, and the thickness of the conductive layer (2) is 0.5 μm to 8 μm; or The thickness of the conductive layer (2) is 1 μm.
8. An electrode structure as described in any one of claims 1-4, characterized in that: The active material layer (3) is a positive electrode active material or a negative electrode active material, and the thickness of the active material layer (3) is 10-200 μm.
9. A battery, characterized in that: Includes the electrode structure described in any one of claims 1-8.
10. An electrical appliance, characterized in that: Includes the battery as described in claim 9.