Method for preparing high capacity lithium ion cell

Abstract

The invention relates to a high capacity Li ion battery preparing method, mixing anode active matter, conductive additive mixed of two materials, Hypermer as electrode additive and adhesive in mass percent, mixing the mixture into anode paste by solvent, coating the anode paste on aluminum foil, automatically drying into electrode plate on coating machine and grinding into anode and cutting into anode plate; mixing cathode active matter, conductive agent and adhesive into paste by solvent and coating the paste on copper foil, drying into electrode plate, cutting out white edge and grinding into cathode, and cutting into cathode plate; coiling anode plate, cathode plate and diaphragm together into electric core, putting in a case, injecting electrolyte and sealing. And it increases battery capacity, and effectively reduces electrode thicknesses. And it provides beneficial help for research and production of high capacity Li ion batteries.

Description

technical field [0001] The invention belongs to the technical field of lithium-ion batteries, in particular to a preparation method of a high-capacity lithium-ion battery. Background technique [0002] At present, taking the ICR1865 lithium-ion battery that is widely used in the market as an example, the preparation method is: [0003] The production of the positive electrode: the mass percentage is 89%-92% of lithium cobaltate, 4%-9% of acetylene black, carbon powder, graphite as a conductive additive, 3%-6% of polytetrafluoroethylene, poly Vinylidene fluoride, one of the polymeric resins, is used as a binder, and N-methylpyrrolidone or dimethylamide, dimethylacetamide is used as a solvent to make a paste, and a 20um thick aluminum foil is used as a current collector. The paste is applied to the aluminum foil and dried, and the pole piece is rolled, and the density of the rolled electrode is 3.3g / cm 3 -3.4g / cm 3 , cut to make a positive electrode sheet; negative electrod...

AI Technical Summary

Problems solved by technology

[0003] The production of the positive electrode: the mass percentage is 89%-92% of lithium cobaltate, 4%-9% of acetylene black, carbon powder, graphite as a conductive additive, 3%-6% of polytetrafluoroethylene, poly Vinylidene fluoride, one of the polymeric resins, is used as a binder, and N-methylpyrrolidone or dimethylamide, dimethylacetamide is used as a solvent to make a paste, and a 20um thick aluminum foil is used as a current collector. The paste is applied to the aluminum foil and dried, and the pole piece is rolled, and the density of the rolled electrode is 3.3g / cm 3 -3.4g / cm 3 , cut to make a positive electrode sheet; negative electrode production: 89%-90% of artificial graphite, modified natural graphite as the negative electrode active material, such as with 2% to 7% of the conductive agent (same as above), 4% to 9% The binder (same as above), using N-methylpyrrolidone (same as above) as a solvent, adjust it into a paste, use a 10um thick copper foil as a current collector, apply the paste on the copper foil, and dry, grind Pressing, shearing and other operations to make negative electrode sheets; the positive and negative electrode sheets processed above are wound into batteries with a composite film of polypropylene resin and polyethylene resin as a diaphragm, put into the shell, and inject organic non-aqueous electrolyte And seal, this organic non-aqueous electrolyte, it is carried out after chemical conversion; The preparation of this method, because the problem of the amount of inactive material in electrode density, battery system, causes lithium-ion battery capacity can not improve, is difficult to meet practical needs