High-recovery battery negative electrode slurry, preparation method thereof and lithium battery

Abstract

The invention relates to a preparation method of high-restorability battery negative electrode slurry, which comprises the following steps: mixing negative electrode graphite and a conductive agent, stirring and dispersing to obtain a dry powder mixture; preparing a CMC solution and dividing the CMC solution into a first CMC solution and a second CMC solution, wherein the first CMC solution accounts for 40-60% of the mass fraction of the prepared CMC solution; adding a first CMC solution into the dry powder mixture, and stirring and dispersing to obtain a first mixed solution; adding a second CMC solution and water into the first mixed solution, performing stirring and dispersing, obtaining a second mixed solution, wherein the solid content of the second mixed solution is 50%-60%; and adding an SBR solution into the second mixed solution, and stirring and dispersing to obtain the product. Through the mode, the viscosity of the battery negative electrode slurry is increased, the slurry leveling property is reduced, the sagging becomes good, the infiltration angle becomes large in the sagging and die head extrusion process, then a thin area is shortened, and the battery capacity is correspondingly increased.

Description

technical field [0001] The invention relates to the technical field of batteries, in particular to a high recovery battery negative electrode slurry, a preparation method thereof and a lithium battery. Background technique [0002] The formation of negative electrode coating thinning area-the coating process is actually a spreading and wetting process of the slurry on the substrate, and the slurry can be spread on the substrate, requiring its surface tension to be lower than the surface energy of the substrate. There is a contact angle at the edge of the coating slurry, which is defined as the angle between the gas-liquid interface tangent and the solid-liquid interface at the intersection of gas, liquid and solid. When the included angle is less than 90 degrees, the slurry can wet the substrate, and the distance from the three-phase intersection point to the stable point of wet film thickness is the thinning zone. The schematic diagram of the contact angle and the thinned ...

AI Technical Summary

Problems solved by technology

This adjustment method is complicated and cumbersome to operate, and the parameters need to be adjusted continuously until the required thin zone length is reached. Secondly, this adjustment method is greatly affected by the properties of the slurry and the assembly of the die head, and the adjustment range is limited.

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