Nonaqueous electrolyte of lithium ion battery and lithium ion battery

Abstract

The invention provides nonaqueous electrolyte of a lithium ion battery and the lithium ion battery. The nonaqueous electrolyte is prepared from an organic solvent, lithium salt and an additive. The nonaqueous electrolyte is characterized that the additive is prepared from tris(trimethylsiloxy)boron, tert-butyl peroxybenzoate and trimethylsilyldiethylamine. According to the nonaqueous electrolyte of the lithium ion battery, disclosed by the invention, by jointly adding the tris(trimethylsiloxy)boron, the tert-butyl peroxybenzoate and the trimethylsilyldiethylamine into the nonaqueous electrolyte, the side reaction between an electrode and electrolyte is greatly reduced; meanwhile, the prepared battery shows good high-temperature storage ability and high-temperature cycling performance.

Description

technical field [0001] The invention belongs to the field of lithium ion batteries, in particular to a nonaqueous electrolytic solution for a lithium ion battery and a lithium ion battery containing the nonaqueous electrolytic solution. Background technique [0002] Lithium-ion batteries are widely cited for their advantages of high voltage, high capacity, low consumption, no memory effect, no pollution, and small size; but in non-aqueous electrolyte secondary batteries, the electrodes will react with the electrolyte and generate gas. It has a great impact on the charging and discharging performance and safety performance of the battery. [0003] In the prior art, there are literatures disclosing that by adding fluorobenzene ring, hexylbenzene or cyclohexylfluorobenzene in the electrolyte to achieve the purpose of inhibiting the reaction of the positive or negative electrode with the non-aqueous electrolyte, although this method can inhibit the The reaction between the posi...

AI Technical Summary

Problems solved by technology

[0002] Lithium-ion batteries are widely cited for their advantages of high voltage, high capacity, low consumption, no memory effect, no pollution, and small size; but in non-aqueous electrolyte secondary batteries, the electrodes will react with the electrolyte and generate gas. It has a great impact on the charging and discharging performance and safety performance of the battery

[0003] In the prior art, there are literatures disclosing that by adding fluorobenzene ring, hexylbenzene or cyclohexylfluorobenzene in the electrolyte to achieve the purpose of inhibiting the reaction of the positive or negative electrode with the non-aqueous electrolyte, although this method can inhibit the The reaction between the positive and negative active materials and the non-aqueous electrolyte, but due to the high viscosity and low stability of this type of addition, it will also affect the overall performance of the non-aqueous electrolyte; Adding sulfonic acid ester, sulfuric acid ester or sulfonic acid ester or sulfuric acid ester and tri(trimethylsilyl) phosphate in the electrolyte can solve the above-mentioned technical problems, because this type of additive can form a dense interfacial film on the surface of the negative electrode, which can be easily Good barrier negative electrode and the side reaction between non-aqueous electrolyte; patent CN201510952221.3 discloses a kind of non-aqueous electrolyte, in its disclosed non-aqueous electrolyte, add fluoroethylene carbonate, three (trimethyl Silane) borate and sulfuric acid ester form a stable SEI film on the surface of the silicon-carbon negative electrode through synergistic action. Although the above two methods can suppress the side reaction between the electrode and the electrolyte to a certain extent, the method is prepared. The high-temperature storage and high-temperature cycle of the battery are poor, and there are problems of gas production and rapid capacity decay in high-temperature environments