Process for preparing Lithium ionic cell electrode slurry using ultrasonic-mechanical raking combination method

Abstract

The invention discloses a process for preparing lithium ion battery electrode paste by employing supersonic-mechanical stirring combining method, including following steps: binder and solvent are filled into a material tank to process mechanical stirring treatment with speed of 300 to 400 rpm, and after the binder is fully dissolved, conductive agent is added in, keeping on stirring for 0.5 to 1 hour; the mixed liquid is transferred into a hydrodynamic supersonic generator by a liquid pump for executing supersonic treatment, wherein the outlet pressure of the liquid pump is 0.1 to 2 MPa, the flowing speed is 1 to 40 m, the sound intensity of the supersonic is 180 to 240 dB; the mixed liquid treated by supersonic is returned to the material tank for stirring, in this manner, the mixed liquid needs to be circulated between the supersonic generator and the material tank for 1 to 1.5 hours; at last, battery active material is added into the material tank, going on stirring for 1.5 to 2 hours, and then well-mixed electrode paste can be obtained. The invention principally employs the supersonic cavitation to disperse the agglomerate conductive agent particles in short time, and to prevent agglomeration again thereby realizing high dispersion of the conductive agent in the electrode paste.

Description

technical field [0001] The invention relates to a preparation process of lithium ion batteries, in particular to a process for preparing electrode slurry in the production of lithium ion batteries. Background technique [0002] In the production process of lithium-ion batteries, the preparation of electrode paste is the first step. At present, the pulping process commonly used at home and abroad is to add electrode active materials, conductive agents, binders, binder solvents, etc. into the mixing tank in a certain proportion, and use mechanical stirring to mix the electrode slurry evenly. Since the particles of commonly used conductive agent carbon black or acetylene black are very small, generally around 50nm, it is easy to form agglomerated particles, and the serious agglomeration of conductive agent particles often leads to cracking of the coated electrode sheet during charging and discharging, and further The cycle life of the battery is reduced. Although the current ...

AI Technical Summary

Problems solved by technology

Since the particles of commonly used conductive agent carbon black or acetylene black are very small, generally around 50nm, it is easy to form agglomerated particles, and the serious agglomeration of conductive agent particles often leads to cracking of the coated electrode sheet during charging and discharging, and further Decrease the cycle life of the battery

Although the current pulping process can play a certain role in the dispersion of the conductive agent, the effect is not good

There are also some pulping processes that use ball milling and colloid milling to further disperse the conductive agent after the slurry is formed, but the effect is not ideal

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