阅读说明：本技术 一种锂电池铝箔的表面涂碳方法 (Surface carbon coating method for lithium battery aluminum foil ) 是由 杜洪彦 宁宏军 赵海刚 于 2019-09-03 设计创作，主要内容包括：本发明公开了一种锂电池铝箔的表面涂碳方法,属于锂电池铝箔加工技术领域,包括以下步骤：S1、选溶液：选取一定浓度的弱碱性溶液,待用；S2、浸泡：将铝箔置入弱碱性溶液中,浸泡,待用；S3、风干：将浸泡后的铝箔取出,使用工业冷风机对其进行风干,待用；S4、涂碳：在特定环境下,在铝箔表面连接导电层,本发明提高了导电能力、降低了界面电阻、提高了电池的低温放电能力、延长了循环寿命,工序科学合理。(The invention discloses a surface carbon coating method of a lithium battery aluminum foil, belonging to the technical field of lithium battery aluminum foil processing, comprising the following steps: s1, selecting a solution: selecting a weak alkaline solution with a certain concentration for later use; s2, soaking: putting the aluminum foil into a weak alkaline solution, and soaking for later use; s3, air drying: taking out the soaked aluminum foil, and air-drying the aluminum foil by using an industrial air cooler for later use; s4, carbon coating: in a specific environment, the surface of the aluminum foil is connected with the conductive layer, so that the conductive capacity is improved, the interface resistance is reduced, the low-temperature discharge capacity of the battery is improved, the cycle life is prolonged, and the process is scientific and reasonable.)

1. The surface carbon coating method of the lithium battery aluminum foil is characterized by comprising the following steps of:

s1, selecting a solution: selecting a weak alkaline solution with a certain concentration for later use;

s2, soaking: putting the aluminum foil into a weak alkaline solution, and soaking for later use;

s3, air drying: taking out the soaked aluminum foil, and air-drying the aluminum foil by using an industrial air cooler for later use;

s4, carbon coating: and under a specific environment, connecting a conductive layer on the surface of the aluminum foil.

2. The method as claimed in claim 1, wherein the weak alkaline solution includes but is not limited to Ca (OH) in step S1₂Solution, Na (OH)₂And (3) solution.

3. The method as claimed in claim 2, wherein the Ca (OH) is added with carbon on the surface of the aluminum foil₂The concentration of the solution is 10-15%, the Na (OH)₂The concentration of the solution is 10-15%.

4. The method as claimed in claim 1, wherein the soaking time in step 2 is 45-60 min.

5. The method as claimed in claim 1, wherein the air drying time is 20-30min in step S3.

6. The method as claimed in claim 1, wherein the specific atmosphere is vacuum or inert gas in step S4.

7. The method as claimed in claim 6, wherein the inert gas includes but is not limited to helium, neon, and argon.

8. The method as claimed in claim 1, wherein the conductive layer is formed as a layer and the conductive layer is connected by sputtering or chemical deposition in step S4.

9. The method as claimed in claim 1, wherein in step S4, the conductive layer is made of materials selected from carbon nanotubes, graphene, and carbon black.

Technical Field

The invention relates to the technical field of lithium battery aluminum foil processing, in particular to a method for coating carbon on the surface of a lithium battery aluminum foil.

Background

The Battery aluminum foil (Battery aluminum foil) is used as a current collector of a lithium ion Battery, generally, the lithium ion Battery industry uses rolled aluminum foil hot rolling as a positive electrode of a negative electrode current collector, the thickness of the rolled foil is different from 10 to 50 micrometers, and common pure aluminum foils of lithium batteries have various alloy designations such as 1060, 1050, 1145 and 1235, and have the states of-O, H14, -H24, -H22 and-H18.

The carbon coating treatment needs to be carried out on the lithium battery aluminum foil in the processing process of the lithium battery aluminum foil, but the existing carbon coating method is convenient, but effective treatment on an oxide layer and oil stains on the surface of the lithium battery is neglected, so that the carbon coating is directly carried out, the conductive capacity is poor, the interface resistance cannot be reduced, the low-temperature discharge capacity of the battery is reduced, the cycle life is shortened, and meanwhile, the carbon coating method is not reasonable, so that the result is unsatisfactory.

Disclosure of Invention

1. Technical problem to be solved

Aiming at the problems in the prior art, the invention aims to provide a method for coating carbon on the surface of an aluminum foil of a lithium battery, which improves the conductivity, reduces the interface resistance, improves the low-temperature discharge capacity of the battery, prolongs the cycle life and has scientific and reasonable working procedures.

2. Technical scheme

In order to solve the problems, the invention adopts the following technical scheme:

a surface carbon coating method for an aluminum foil of a lithium battery comprises the following steps:

s1, selecting a solution: selecting a weak alkaline solution with a certain concentration for later use;

s2, soaking: putting the aluminum foil into a weak alkaline solution, and soaking for later use;

s3, air drying: taking out the soaked aluminum foil, and air-drying the aluminum foil by using an industrial air cooler for later use;

s4, carbon coating: and under a specific environment, connecting a conductive layer on the surface of the aluminum foil.

As a preferred embodiment of the present invention, in step S1, the weak alkaline solution includes but is not limited to Ca (OH)₂Solution, Na (OH)₂And (3) solution.

As a preferred embodiment of the present invention, the Ca (OH)₂The concentration of the solution is 10-15%, the Na (OH)₂The concentration of the solution is 10-15%.

As a preferable embodiment of the present invention, in step S2, the soaking time is 45-60 min.

In a preferred embodiment of the present invention, in step S3, the air drying time is 20-30 min.

As a preferable aspect of the present invention, in step S4, the specific atmosphere is in vacuum or in an inert gas.

As a preferred embodiment of the present invention, the inert gas includes, but is not limited to, helium, neon, and argon.

As a preferable aspect of the present invention, in step S4, the conductive layer is provided as a layer, and the connection manner of the conductive layer is sputtering or chemical deposition.

As a preferred aspect of the present invention, in step S4, the conductive layer may be made of materials including, but not limited to, carbon nanotubes, graphene, and carbon black.

3. Advantageous effects

Compared with the prior art, the invention has the advantages that:

(1) the invention firstly adopts alkaline solution to soak the aluminum foil to remove the oxide layer and oil stain on the surface.

(2) The invention has good effect by sputtering or chemically depositing a conducting layer on the surface of the aluminum foil in vacuum or inert gases such as helium, neon, argon and the like.

(3) After the aluminum foil is coated with the carbon coating layer, the conductivity is improved, the interface resistance is reduced, the low-temperature discharge capacity of the battery is improved, and the cycle life is prolonged.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and all other embodiments obtained by those skilled in the art without any inventive work are within the scope of the present invention.