The effect of Electrolyte Solvent on the Performance of the LiMn۲O۴ Cathodefor Lithium-ion Battery Application

Electrolyte solvents play a key role in battery performances and cyclic stability of lithium-ion batteries(LIBs). In this work, we have studied the effect of three solvents, including propylene carbonate (PC),ethylene carbonate (EC), and dimethyl carbonate (DMC), on the cyclic performance of theLiMn۲O۲/Celgard/Li half-cells. The electrolytes were prepared by dissolving LiClO۴ in PC and EC/DMCsolvents (۱ M). The cells assembled using PC solvent lost their initial specific capacity after a fewcharge/discharge cycles. To mitigate this issue, the combination of EC and DMC was used as an alternativeelectrolyte solvent and compared with PC. The electrochemical performance of Lithium manganese oxideLiMn۲O۲ half cells was significantly enhanced. The discharge capacity of cells containing EC/DMC andPC solvents was ۹۴.۹۳ mAh g-۱ and ۴۸.۷۶ mAhg-۱, respectively, after ۱۰۰ cycles of charge/discharge withthe current density of ۰.۵ C. The capacity retention of cells containing EC/DMC and PC solvents was ۶۷%and ۵۴.۷%, respectively. These enhancements mainly corresponded to the dielectric constant and viscosityof solvents that caused an increase in ionic conductivity of the electrolyte and overall performance of theassembled batteries.

Keywords:

Lithium-ion battery , Propylene carbonate , Ethylene carbonate , Dimethyl carbonate , LiMn۲O۲ , cathode