Lithium ion battery non-aqueous electrolyte and lithium ion battery

Abstract

The invention discloses a lithium ion battery non-aqueous electrolyte and a lithium ion battery, comprising an electrolyte, a non-aqueous organic solvent and an additive, wherein the additive comprises the mixture of a compound A, a compound B, vinylene carbonate and 1,3-propane sultone; the compound A introduces a cyano group based on a phosphate-containing group, and the compound B acts as a high-temperature heat stabilizer. The interaction between the compound A and the compound B effectively reduces the interfacial impedance of the lithium battery, and improves the high temperature and lowtemperature performance of the lithium battery while taking into account the thermal stability of the electrolyte.

Description

technical field [0001] The invention relates to a lithium ion battery electrolyte and a lithium ion battery, in particular to a lithium ion battery non-aqueous electrolyte and a lithium ion battery. Background technique [0002] At present, the electrolyte used in the existing industrial manufacturing of lithium-ion batteries is mainly LiPF 6 、LiBF 4 、LiCLO 4 , LiI, etc., the electrolyte concentration is 0.1-2.0mol / L, and EC-PC-DMC-DEC-EMC (where EC is ethylene carbonate, PC is propylene carbonate, DMC is dimethyl carbonate, DEC is diethyl carbonate , EMC is ethyl methyl carbonate) and other organic substances are solvents. [0003] The electrolyte has a great influence on the performance of lithium batteries, mainly because the composition, concentration, viscosity, and conductivity of the electrolyte are related to the electrode surface reaction. The conductivity of the electrolyte and the reversibility of the electrode reaction directly affect the discharge capacity o...

AI Technical Summary

Problems solved by technology

However, it has been found through research that the interface passivation film formed by additives containing phosphate groups is relatively thick, and the battery impedance is relatively large, resulting in poor low-temperature performance.

[0005] The high-nickel ternary lithium-ion battery electrolyte is currently unable to take into account the high and low temperature performance of the lithium battery. The interface impedance is high and the thermal stability of the electrolyte is poor, so it is easy to decompose at high temperature to produce HF, corrode the interface and diaphragm, and produce colored substances.

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