Composite current collector with high adhesive force and lithium ion battery

Abstract

The utility model provides a composite current collector with high adhesive force and a lithium ion battery. The composite current collector comprises a middle insulating layer, a first electrode and a second electrode, the adhesion promoting layers are arranged on the two sides of the middle insulating layer; the sputtering metal layer is arranged on the surface of the adhesion promoting layer in a sputtering mode; the electroplated metal layer is arranged on the surface of the sputtered metal layer in a sputtering manner; and the high adhesive force layer is arranged on the surface of the electroplated metal layer. According to the composite current collector, the high-adhesion layer with high adhesion is coated on the surface of the electroplated metal layer, so that the contact area and the binding force of the composite current collector and an active material are improved, and the performance of the lithium ion battery is improved.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and more specifically, to a composite current collector with high adhesion and a lithium-ion battery. Background Technology

[0002] Traditional negative electrode current collector materials are pure metal foils, such as copper foil and aluminum foil. Composite current collectors, on the other hand, are sandwich structures formed by an insulating polymer layer in the middle and metal layers plated on both sides. Composite current collectors can improve the safety performance of lithium-ion batteries and increase battery energy density by reducing weight. Current collectors play an important role in lithium-ion battery systems, including collecting electrons and transporting current.

[0003] The interface between the current collector and the active material has a significant impact on the performance of lithium-ion batteries. The effective contact between the current collector and the active material is limited, the bonding strength is not high enough, and the current collector is corroded by contact with the electrolyte. These problems severely limit the further improvement of the performance of lithium-ion batteries. Traditional pure metal foil materials can be improved by surface roughening. However, chromium is a toxic heavy metal that easily creates contact area between the current collector and the active material during the preparation process. Moreover, the metal layer of the composite current collector is relatively thin, making it difficult to perform roughening treatment. Utility Model Content

[0004] This invention discloses a composite current collector with high adhesion and a lithium-ion battery to improve the above-mentioned problems.

[0005] The present invention adopts the following solution:

[0006] A composite current collector with high adhesion, comprising:

[0007] Intermediate insulating layer;

[0008] An adhesion-promoting layer is disposed on both sides of the intermediate insulating layer;

[0009] A sputtered metal layer is deposited on the surface of the adhesion-promoting layer by sputtering.

[0010] An electroplated metal layer is deposited on the surface of the sputtered metal layer by sputtering.

[0011] A high-adhesion layer is disposed on the surface of the electroplated metal layer.

[0012] Preferably, the material of the intermediate insulating layer is one of PET, PP, or PI.

[0013] Preferably, the thickness of the intermediate insulating layer is 2-12 μm.

[0014] Preferably, the adhesion promoting layer is made of an existing copper-nickel alloy or nickel-chromium alloy.

[0015] Preferably, the thickness of the adhesion promoting layer is 1-50 nm.

[0016] Preferably, the sputtered metal layer is made of copper and has a thickness of 30-100 nm.

[0017] Preferably, the material of the electroplated metal layer is copper, and its thickness is 500-5000 nm.

[0018] Preferably, the high adhesion layer is a nano-metal coating.

[0019] Preferably, the thickness of the high adhesion layer is 1-5 μm.

[0020] This utility model embodiment also provides a lithium-ion battery, which includes the composite current collector with high adhesion as described above.

[0021] In summary, this embodiment of the invention improves the performance of lithium-ion batteries by coating a high-adhesion layer with a high-adhesion layer on the surface of the electroplated metal layer, thereby increasing the contact area and bonding force between the composite current collector and the active material. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the structure of the composite current collector with high adhesion provided in the embodiment of this utility model. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model. Therefore, the following detailed description of the embodiments of this utility model provided in the accompanying drawings is not intended to limit the scope of the claimed utility model, but merely represents selected embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0025] Please see Figure 1 The first embodiment of this utility model provides a composite current collector with high adhesion, which includes:

[0026] Intermediate insulation layer 10.

[0027] In this embodiment, the material of the intermediate insulating layer 10 is selected from PET, PP, and PI, and its thickness can be 2-12μm.

[0028] For example, a 6μm thick PET film can be selected. By testing the insulation resistivity of the PET film, if it reaches 10^15 Ω·cm or higher, it meets the insulation performance requirements.

[0029] An adhesion promoting layer 20 is disposed on both sides of the intermediate insulating layer 10.

[0030] In this embodiment, the adhesion promoting layer 20 may be made of copper-nickel alloy or nickel-chromium alloy, and its thickness is 1-50 nm.

[0031] For example, a 12nm thick copper-nickel alloy layer can be sputtered on both sides of a PET film as an adhesion promoting layer 20 using magnetron sputtering.

[0032] It should be noted that the copper-nickel alloy or nickel-chromium alloy used in the adhesion promoting layer 20 are existing technologies and are conventional composite current collector preparation processes. They do not involve any improvement to the components, and will not be described in detail here.

[0033] A sputtered metal layer 30 is deposited on the surface of the adhesion promotion layer 20 by sputtering.

[0034] The sputtered metal layer can be made of copper and has a thickness of 30-100 nm.

[0035] For example, a 40 nm thick copper layer can be sputtered on the surface of the adhesion promotion layer 20 as the sputtering metal layer 30.

[0036] An electroplated metal layer 40 is deposited on the surface of the sputtered metal layer 30 by sputtering.

[0037] The material of the electroplated metal layer 40 can be copper, and its thickness is 500-5000nm.

[0038] For example, a 1 μm thick copper layer can be electroplated onto the surface of the sputtered metal layer 30 to form an electroplated metal layer 40.

[0039] A high adhesion layer 50 is disposed on the surface of the electroplated metal layer 40.

[0040] The high adhesion layer 50 can be made of conductive coating slurry, which can be applied to the surface of the electroplated metal layer 40 by spraying, roller coating, brushing or spraying, and has a thickness of 1-5μm.

[0041] In this embodiment, specifically, the conductive coating slurry may be composed of nanoparticle conductive agents, binders, deionized water, and neutralizing agents. For example, the conductive coating slurry disclosed in Chinese Patent CN113248989A is composed of 150-400 parts binder, 20-100 parts conductive agent, 100-600 parts deionized water, and 2-10 parts neutralizing agent.

[0042] Of course, additional components, such as pore-forming agents, can be added to the conductive coating slurry. Furthermore, the composition of the conductive coating slurry can be adjusted according to actual needs, all of which are within the scope of protection of this utility model.

[0043] This utility model embodiment also provides a lithium-ion battery, which includes the composite current collector with high adhesion as described above.

[0044] In summary, this embodiment of the invention improves the contact area and bonding force between the composite current collector and the active material by coating a high-adhesion layer 50 with a high-adhesion layer 40 on the surface of the electroplated metal layer 40, thereby enhancing the performance of the lithium-ion battery.

[0045] The above are merely preferred embodiments of this utility model. The protection scope of this utility model is not limited to the above embodiments. All technical solutions that fall within the scope of this utility model's concept are protected by this utility model.

Claims

1. A composite current collector having high adhesion, characterized by, Comprise: An intermediate insulation layer; An adhesion promotion layer disposed on both sides of the intermediate insulation layer; A sputtered metal layer disposed on the surface of the adhesion promotion layer by sputtering; An electroplated metal layer disposed on the surface of the sputtered metal layer by sputtering; A high adhesion layer disposed on the surface of the electroplated metal layer.

2. The composite current collector with high adhesion according to claim 1, wherein the material of the intermediate insulation layer is one of PET, PP and PI.

3. The composite current collector with high adhesion according to claim 1, wherein the thickness of the intermediate insulation layer is 2-12 μm. The adhesion promotion layer uses existing copper-nickel alloy or nickel-chromium alloy. The thickness of the adhesion promotion layer is 1-50 nm.

4. The composite current collector with high adhesion according to claim 1, wherein 6. The composite current collector with high adhesion according to claim 1, wherein the material of the sputtered metal layer is copper, and the thickness is 30-100 nm.

5. The composite current collector with high adhesion according to claim 1, wherein 7. The composite current collector with high adhesion according to claim 1, wherein the material of the electroplated metal layer is copper, and the thickness is 500-5000 nm. The high adhesion layer is a nano-metal coating. The thickness of the high adhesion layer is 1-5 μm. A battery comprising the composite current collector with high adhesion according to any one of claims 1 to 9. ​ 8. The composite current collector with high adhesion according to claim 1, wherein ​ 9. The composite current collector with high adhesion according to claim 1, wherein ​ 10. A lithium-ion battery, characterized by, ​

Images