Aminoalkyldisiloxane compound as efficient high-temperature electrolyte additive for LiMn2O4/graphite batteries

LiMn2O4 batteries have been widely used as power batteries due to the advantages of high safety, low cost, and higher capacities as compared to their LiFePO4 counterparts. However, their cycling stabilities under elevated temperatures remain a significant challenge in practical applications. We herein report an effective electrolyte additive of (3-(N, N-dimethylamino) diethoxypropyl) pentamethyldisiloxane (DSON) to improve the high-temperature electrochemical performance of LiMn2O4 cells. The LiMn2O4/graphite cell using an optimized addition level of 0.5 wt% shows an increased capacity retention of 56.8% compared to 36.8% for that using the baseline electrolyte after 50 cycles at 60 degrees C. X-ray photoelectron spectra reveal that DSON compound can also form a robust cathode electrolyte interface on the surface of LiMn2O4 cathode. The dissolution of Mn from LiMn2O4 cathode is effectively suppressed in LiMn2O4/Li cell after 200 cycles at 60 degrees C, due to the formed cathode electrolyte interface and the inhibited hydrolysis of LiPF6 salt in the electrolyte at the presence of DSON additive. This work demonstrates that DSON is a promising electrolyte additive for improving the cycling stability of LiMn2O4 batteries at high temperatures.

Automated summary

This study reports an electrolyte additive, DSON, that can improve the electrochemical performance of LiMn2O4 batteries at high temperatures. LiMn2O4/graphite cells using DSON additive show higher capacity retention and effective suppression of manganese dissolution.