Electrolyte and lithium ion battery

By using specific compounds to form a stable SEI film in lithium-ion batteries, the problem of electrolyte degradation during cycling at room temperature and high temperature is solved, achieving high-efficiency cycle performance and long lifespan of the battery.

CN116130763BActive Publication Date: 2026-06-30EVE POWER CO LTD
View PDF 4 Cites 0 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
EVE POWER CO LTD
Filing Date
2022-11-29
Publication Date
2026-06-30

AI Technical Summary

Technical Problem

Existing lithium-ion batteries experience side reactions in the electrolyte during both room temperature and high temperature cycling, which damages the SEI film structure, deteriorates cycle performance, and shortens battery life.

Method used

An electrolyte containing specific compounds is used to form a dense and stable SEI film. Through rapid ring-opening polymerization on the negative electrode surface, an elastic SEI film is formed preferentially over carbonate solvents, which captures hydrofluoric acid, repairs the SEI film damaged during cycling, and improves the cycle performance of the battery.

Benefits of technology

It significantly improves the room temperature and high temperature cycle performance of lithium-ion batteries. At 25℃, the capacity retention rate is higher than 92% after 2000 cycles of 0.5C/5C, and at 45℃, the capacity retention rate reaches 88% after 1500 cycles of 1C/1C, thus extending battery life.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure QLYQS_1
    Figure QLYQS_1
  • Figure QLYQS_2
    Figure QLYQS_2
  • Figure QLYQS_3
    Figure QLYQS_3
Patent Text Reader

Abstract

This invention provides an electrolyte and a lithium-ion battery. The electrolyte includes a primary electrolyte and a secondary electrolyte. The primary electrolyte includes a compound as shown in Formula 1, an organic solvent, a lithium salt, and an additive. The secondary electrolyte includes a compound as shown in Formula 1, an organic solvent, and a lithium salt. The primary electrolyte is used for primary electrolyte filling, and the secondary electrolyte is used for secondary electrolyte filling. When R1 and R2 are linked, R1, R2, and carbon atoms form a multi-component nitrogen heterocycle or a multi-component ring, with the number of carbon atoms ≥ 0. When R1 and R2 are not linked, R1 and R2 are independently selected from alkyl, olefinic, alkyneic, or phenyl groups. R3 is selected from hydrogen atoms, alkyl, olefinic, alkyneic, or benzyl groups. The lithium-ion battery electrolyte prepared by this invention can form a stable and dense SEI film at the negative electrode, improving the battery's room temperature and high temperature cycle performance.
Need to check novelty before this filing date? Find Prior Art