Modification method of graphite negative plate of lithium ion battery

Abstract

The invention provides a method for modifying a graphite negative plate by laser etching for a lithium ion battery. The prepared graphite negative electrode plate which is not treated is placed under a laser probe, and laser parameters are adjusted. And under the condition that the overall structure of the graphite negative plate is not damaged, the surface of the graphite negative plate is subjected to laser etching, so that gullies and defects are formed, and a final product is obtained. The problems that in the prior art, traditional heat treatment, chemical etching, mechanical activation and other procedures are complex, the environment is polluted, and energy consumption is large are solved. The electrochemical performance of the graphite electrode after laser etching is remarkably improved, the graphite electrode shows the specific discharge capacity of 300-450 mAh / g under the current density of 50 mA / g, still has the capacity of 120-350 mA / g after 300 cycles under the current density of 1 A / g, and has high specific discharge capacity and good cycle stability. The method provides a simple, green and universal strategy for structural modification and performance improvement of the graphite negative plate.

Description

Technical field: [0001] The invention relates to the field of lithium ion battery materials, and provides a method related to laser etching modified graphite negative electrode sheet and its application as a lithium ion battery negative electrode. Background technique: [0002] As an important part of the secondary energy storage battery, the anode material plays a decisive role in its performance. Among them, graphite has become the most commercialized negative electrode material due to its rich resources, low cost, environmental friendliness, low charge and discharge voltage platform, and good stability. Although there are many materials with high specific capacity to choose from (such as Si, Sn, Sb, and metal oxides), these materials are usually accompanied by disadvantages such as low density, low Coulombic efficiency, and high potential platform, which lead to their practical application. The value is far lower than that of graphite materials. In the next few decades,...

AI Technical Summary

Problems solved by technology

However, the specific surface area and defects of the sample increase, and the first Coulombic efficiency decreases

At the same time, there are still problems such as cumbersome process, high energy consumption, environmental pollution, equipment corrosion, product repeatability and poor controllability of morphology and structure.

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