Positive electrode material for lithium battery

Abstract

The invention discloses a positive electrode material for a lithium battery, and the material comprises a positive electrode active substance, a binder, a conductive agent, a conductive enhancer, a dispersing agent and a slurry mixing solvent, wherein the mass percentages of all components are as follows: 60-80% of the positive electrode active substance; 5-10% of the binder, 6-12% of the conductive agent, 4-6% of the conductive enhancer, 0.25-1% of the dispersing agent, 1-3% of an auxiliary agent and 3-6% of the slurry mixing solvent. The slurry mixing solvent is a mixed solvent formed by mixing N, N-dimethylacetamide, dimethyl sulfoxide, tetramethylurea, trimethyl phosphate, dimethylformamide and water. The material achieves the purposes that the lithium battery is moderate in cost, thehigh-temperature performance is excellent, the capacity retention ratio is high, the cycle performance is good and the service life is long.

Description

technical field [0001] The invention relates to the technical field of lithium batteries, in particular to a lithium battery cathode material. Background technique [0002] With the wide application and rapid development of lithium batteries, people have higher and higher performance requirements for lithium-ion batteries, which not only require lithium batteries to have a higher capacity, but also require better capacity retention during repeated charging and discharging. rate, exhibits good cycle performance, and has a long service life. The main constituent materials of lithium batteries include electrolyte, isolation materials, positive and negative electrode materials, etc. The positive electrode material occupies a large proportion (the mass ratio of positive and negative electrode materials is 3: 1 ~ 4: 1), because the performance of the positive electrode material directly affects the performance of the lithium-ion battery, and its cost also directly determines the ...

AI Technical Summary

Problems solved by technology

Lithium cobalt oxide has the advantages of high working voltage, stable charge and discharge voltage, and high conductivity, but it is expensive and has poor overcharge resistance.

Lithium manganese oxide has the advantages of cheap price and high safety, but its capacity is not high, and it is prone to structural deformation during charging and discharging, making it unstable.

Lithium iron phosphate has the advantages of high safety, moderate price and environmental protection, but the capacity is not high and the conductivity is not high

Ternary materials have the advantages of excellent cycle performance and high capacity, but the price is slightly expensive, and the rate performance and energy density are low