Chromium-free anti-oxidation solution and anti-oxidation process for electrolytic copper foil for lithium ion batteries

Abstract

The invention relates to a chromium-free anti-oxidation solution and anti-oxidation process for electrolytic copper foil for lithium ion batteries. The chromium-free anti-oxidation solution per litercomprises, 0.2-2.0 g of benzotriazole, 0.1-1.2 g of benzoic acid, 0.1-1.0 g of propyl acetate, and water as a solvent. The process for performing anti-oxidation treatment on the electrolytic copper foil through the chromium-free anti-oxidation solution comprises the following steps that the original foil enters the chromium-free anti-oxidation solution for soaking through a guide roller after being stripped through a cathode roller, the temperature of the chromium-free anti-oxidation solution is controlled to be 20-35 DEG C in the soaking process, the soaking time is 3-10 s, then the foil is squeezed to be dry through a squeezing roller, a high-pressure air knife blows the foil to dry the foil at the normal temperature, and then the foil is directly coiled. The chromium-free anti-oxidationsolution has the beneficial effects that the solution does not contain the chromium element causing cancers to human beings or the zinc elementary substance reducing performance of the battery; by application of the anti-oxidation solution, powering on is avoided, and a passivation layer is formed completely in a chemical plating mode; and water washing is needed, and the situations that waste water pollutes the environment and cost is increased are avoided.

Description

technical field [0001] The invention relates to a chrome-free anti-oxidation solution and an anti-oxidation process for electrolytic copper foil used in lithium ion batteries, and belongs to the technical field of surface treatment of electrolytic copper foil. Background technique [0002] In recent years, the country has paid more and more attention to the new energy power lithium-ion battery industry, and introduced many preferential policies, which has promoted the rapid development of electrolytic copper foil for power lithium-ion batteries. Due to the special requirements for anti-oxidation of the surface of electrolytic copper foil for lithium-ion batteries, the traditional anti-oxidation process of copper foil surface is no longer suitable for the requirements of environmentally friendly lithium-ion batteries. [0003] At present, 8-micron single-sided and double-sided ultra-thin electrolytic copper foil is the mainstream of high-quality lithium-ion battery negative e...

AI Technical Summary

Problems solved by technology

[0005] (1) Contains chromium element that can cause cancer to the human body, which will cause harm to the operator's body;

[0006] (2) Some need to be dried in a high-temperature oven, and the high temperature leads to a particularly high temperature in the sealed winding house, which is not suitable for personnel operation;

[0008] (4) Some passivation solutions contain zinc, and metal zinc is formed on the surface of copper foil after electrodeposition. Zinc alone can form a primary battery under the electrolyte in the battery, reducing the capacity and charge-discharge performance of the battery, and even causing an explosion.

[0009] (5) Some copper foils need to be washed with water after passing through the anti-oxidation tank, which will produce chromium-containing wastewater, which will not only pollute the environment, but also increase the cost of water treatment

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