S. Bae, Won-Kyung Shin, Dong‐Won Kim
Apr 10, 2014
Citations
2
Influential Citations
37
Citations
Journal
Electrochimica Acta
Abstract
Abstract Dimethylacetamide (DMAc) and triethyl(2-methoxyethyl)phosphonium bis(trifluoromethylsulfonyl)imide (TEMEP-TFSI) are investigated as protective additives for high voltage LiNi 0.5 Mn 1.5 O 4 cathode materials. The capacity retention of Li/LiNi 0.5 Mn 1.5 O 4 cells is improved by adding these additives to the base liquid electrolyte. The self-extinguishing time and DSC results demonstrate that the addition of TEMEP-TFSI to the base electrolyte is effective in reducing the flammability of the electrolyte solution and improving the thermal stability of the LiNi 0.5 Mn 1.5 O 4 electrode. TEM and XPS analyses of the LiNi 0.5 Mn 1.5 O 4 electrode reveal that DMAc and TEMEP-TFSI participate in the formation of a stable solid electrolyte interphase (SEI) on the LiNi 0.5 Mn 1.5 O 4 electrode, and the resulting SEI layer effectively suppresses electrolyte decomposition.