Ethylene glycol bis (propionitrile) ether (EGBE) is used as an electrolyte additive to improve the cycling stability and rate capability of Li/Li1.2Mn0.54Ni0.13Co0.13O2 cells at high operating voltage (4.8 V). After 150 cycles, cells with 1.0 wt% of EGBE-containing electrolytes have remarkable cycling performance and 89.0% capacity retention, while the cells with baseline electrolytes only remain at 67.4% capacity retention. EGBE preferably oxidizes on the cathode surface compared to the LiPF6/carbonate electrolyte. The improved cycling performance can be attributed to more stable and robust surface layer yield via the incorporation of EGBE, which mitigates the oxidation of electrolytes on the cathode electrode and inhibits the dissolution of bulk transition metal ions upon cycling at high voltage[1].
The preparation method of ethylene glycol bis (propionitrile) ether is as follows: with ethylene glycol and acrylonitrile as reaction raw materials, reaction under the catalysis of reaction temperature 30 ℃～70 and aqueous catalyst solution generates ethylene glycol bis (propionitrile) ether. The described aqueous catalyst solution is the compound base catalyst aqueous solution, and this compound base catalyst aqueous solution is mixed with a triethyl benzyl ammonium hydroxide aqueous solution and sodium hydrate aqueous solution.
[1] Pengbo Hong . “Effect of ethylene glycol bis (propionitrile) ether (EGBE) on the performance and interfacial chemistry of lithium-rich layered oxide cathode.” Journal of Power Sources 329 (2016): Pages 216-224.
