The characterization of charge-discharge and initial impedance of $LiMn_{2-y}Mg_yO_4$ by change of temperature

온도 변화에 따른 $LiMn_{2-y}Mg_yO_4$의 충방전 및 초기 임피던스 특성

Spinel $LiMn_{2-y}Mn_{y}O_4$ powder was prepared solid-state method by calcining the mixture of $LiOH{\cdot}H_2O$, $MnO_2$ and MgO at $800^{\circ}C$ for 36h. To investigate the effect of temperature for cycle behaviour of cathode material during cycling, charge-discharge experiments and initial impedance spectroscopy performed by the condition of the charge-discharge temperature. Initial charge-discharge capacity was gradually increased by rising charge-discharge temperature. However, capacity was suddenly decreased at high temperature during cycling. Capacity at low temperature was almost constant during cycling. It confirmed because Mn dissolution is more serious at high temperature than at low temperature.