LiPF6-EC-MPC electrolyte for LiMn2O4 cathode in lithium-ion battery

Methyl propyl carbonate (MPC) is a promising single solvent for lithium-ion battery without addition of ethylene carbonate (EC), but it is unstable upon cycling because of exposure to the spinel LiMn2O4 cathode. Thus, we attempted to add EC to MPC in order to form LiPF6-EC-MPC electrolyte; the effects of solvent ratio and salt concentration on the cycling performance of LiMn2O4 cathode were also investigated. The experiments were characterized by conductivity measurements, charge-discharge at a constant current density and voltage–capacity curves at low temperature. To further enhance our understanding of the performance improvement of LiMn2O4/Li cells, the electrochemical characterization techniques (such as, LSV, EIS) were performed on these cells. The results show that the ionic conductivity of the electrolyte and the cycling performance of the spinel LiMn2O4 cathode have been dramatically enhanced. From the point of view of operation at low temperature (− 20 °C), 1 M LiPF6 EC/MPC (1/3) electrolyte is highly recommended for spinel LiMn2O4 cathode in lithium-ion battery.