2015 Volume 83 Issue 9 Pages 707-710
Ionic liquids are of interest for application in electrolytes of lithium-ion batteries, because of their non-flammability, thermal stability, and non-volatility. Electrolytes containing ionic liquids have therefore been used to improve the safety of lithium-ion cells. Both the liquid electrolyte and the gelled electrolyte, which was composed of 1-ethyl-3-methyl-imidazolium tetrafluoroborate and LiBF4, were shown to have good thermal and electrochemical stability and to be applicable for use in lithium-ion cells with Li[Li1/3Ti5/3]O4 as the negative electrode active material. Electrolytes containing a mixture of organic solvents and N-methyl-N-propylpiperidinium bis (trifluoromethane-sulfonyl) imide were also found to exhibit good discharge performance for use in lithium-ion cells and non-flammability for use as an electrolyte. Furthermore, it was found that graphite was able to perform in the electrolyte containing the ionic liquid.