Preparation method for lithium iron phosphate cathode slurry

Abstract

The invention provides a preparation method for lithium iron phosphate cathode slurry. All constituents of the slurry are uniformly dispersed within a short time by steps of powder dispersion, high-viscosity stirring, low-viscosity stirring, viscosity tests, vacuum defoaming and the like. The prepared slurry is high in uniformity and excellent in stability, meanwhile, the adhesive strength of a battery pole piece prepared according to the method is improved, and thus, the consistency and the electrochemical performance of the battery are enhanced. The preparation method has the characteristics of short preparation time, low device abrasion, low production energy consumption, high dispersion effect and the like. A lithium battery prepared from the lithium iron phosphate cathode slurry provided by the invention has low internal resistance, is difficult to generate heat, and also has the advantages of high energy density, good cycle performance and long service lifetime.

Description

Technical field [0001] This patent relates to the field of lithium ion batteries, and specifically relates to a preparation process and method of lithium iron phosphate cathode material slurry. Background technique [0002] With the global shortage of petroleum resources and the continuous deterioration of the climate environment, the development of human society is facing severe challenges. The development of clean and energy-saving new energy vehicles is highly valued by countries all over the world. The key to the development of new energy vehicles is its power source. Lithium-ion batteries have the advantages of high energy density, low self-discharge, no memory effect, wide operating voltage range, long service life, and no environmental pollution. They are currently the main power source for new energy vehicles. [0003] Lithium-ion batteries generally include a positive electrode sheet, a negative electrode sheet, and a separator spaced between the positive electrode sheet...

AI Technical Summary

Problems solved by technology

This method first requires a long time for the dispersion of the conductive agent, which takes a long time and the dispersion state is not ideal, especially for the preparation of the slurry using carbon nanotubes (CNT), graphene, etc. as the conductive agent; secondly, the traditional process requires During the slurry preparation process, the stirring system is kept in a vacuum state, causing the internal temperature of the slurry system to rise easily, and at the same time, circulating water is added to the outside for cooling, so the requirements and wear on the equipment are very high

The above results in low slurry preparation efficiency, poor stability, and unsatisfactory effects, which will affect the preparation of subsequent pole pieces and the performance of lithium batteries.

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