Suppress voltage decay of lithium-rich materials by coating layers with different crystalline states

Abstract

Li-rich oxides are considered as the most commercial potential cathode materials due to the high theoretical specific discharge capacity. Here, ZrO2 in different crystalline states are applied as the coating layers to enhance the electrochemical performance of hollow Li[Li0.2Mn0.54Ni0.13Co0.13]O2 materials. Meanwhile, a series of characterizations (XRD, SEM, TEM, EDX etc.) are conducted to compare the effects of ZrO2 coating layer with different crystalline states on the host material. The results elucidate that the Li-rich Mn-based material with the polycrystal ZrO2 coating layer has a slight advantage in rate performance, while the host material with the single crystal ZrO2-coating layer has a better cycling performance and effectively suppresses voltage decay with the effect of excellently inhibiting layered to spinel-like phase transition and metal dissolution during charging and discharging process.