Graphene ultralow-temperature power lithium battery

Abstract

The invention discloses a graphene ultralow-temperature power lithium battery. The power lithium battery comprises a battery case, a negative electrode insulation sheet, a battery cell, a positive electrode insulation sheet and a cap. The battery cell comprises a positive electrode plate, a negative electrode plate and a diaphragm. The positive electrode plate comprises a positive electrode current collector, and positive electrode material coatings arranged on two side surfaces of the positive electrode current collector respectively; each positive electrode material coating is prepared by coating the surface of the positive electrode current collector with a positive electrode material mixture; and the positive electrode material mixture contains a nanoparticle positive electrode material, a positive electrode binder, a positive electrode mixed conductive agent and a positive electrode solvent, wherein the nanoparticle positive electrode material is a lithium iron phosphate nanoparticle, and the positive electrode mixed conductive agent contains, by weight, 97-99 parts of a positive electrode conductive agent base material, 0.2-0.4 parts of graphene, 0.2-0.4 parts of SP and 0.2-0.4 parts of KS-6.

Description

Technical field [0001] The invention belongs to the technical field of rechargeable batteries, and specifically relates to a lithium ion battery. Background technique [0002] Lithium iron phosphate battery refers to a lithium ion battery that uses lithium iron phosphate as a positive electrode material. Lithium iron phosphate has an olivine structure and has excellent resistance to overcharge and overdischarge. It is widely used in the field of power batteries. Lithium iron phosphate is considered to be the best at present due to its high safety, long cycle life, low price and environmental protection. A promising cathode active material for lithium-ion power batteries. [0003] However, low-temperature performance has always been the bottleneck of lithium iron phosphate power batteries. Compared with other positive electrode active materials, the inherent disadvantage of poor electrical conductivity of lithium iron phosphate materials greatly limits its dynamic characteristics a...

AI Technical Summary

Problems solved by technology

[0015] The purpose of the present invention is to overcome the above deficiencies in the prior art, to provide a graphene ultra-low temperature power lithium battery, to improve the low-temperature discharge performance of lithium iron phosphate power battery, and to solve the problem of low temperature of lithium iron phosphate power battery at a lower cost. Poor electrical conductivity of lithium iron phosphate, significant drop in electrical conductivity of positive / negative electrodes, poor electrolyte permeability, etc.

Images