Synergy Between Experiment and Simulation in Describing the Electrochemical Performance of Mg-doped LiNi_xCo_yMn_zO₂ Cathode Material of Lithium Ion Battery

摘要

Electrically powered vehicles (EV) are the next promising transportation candidate. However, energystorage in EVs is a critical issue if transportation needs are to be met. Recently, three element-layeredstructure materials of the type LiNi0.5Co0.2Mn0.3O2 have found application as cathodes in lithium ionbatteries. However, the performance of this battery type over a wide temperature range is poor, andthis limits its development into the EV market. We report the synthesis of Mg-dopedLi1.1Ni0.497Mg0.003Co0.2Mn0.3O2, prepared by solid-state methods for the improvement of batteryperformance for EV applications. Differential scanning calorimetry (DSC) analysis revealed thatdoping with Mg significantly enhances the thermal structural stability of LiNi0.5Co0.2Mn0.3O2.Additionally, Mg doping increases discharge capacity by 5% and 10% for room- and low-temperature o (10 C) operation, respectively. The increase in thermal stability provided a 66% improvement in theo cycle life at high-temperature (60 C) operation.