First-Principles Characterization of Lithium Cobalt Pyrophosphate as a Cathode Material for Solid-State Li-Ion Batteries

Lithium cobalt pyrophosphate (LCPO) is a promising cathode material for solid-state batteries due to its intrinsic high-voltage characteristic. Using density functional theory calculations, we reveal the structural, magnetic, electronic, and lithium migration properties as well as the effects of silicon doping in LCPO. We found that the Li diffusion rate and charge capacity are strongly related to the intrinsic defects in LCPO, and reducing which could improve both the battery parameters. In addition, we showed that silicon doping on the phosphorus site can enhance the charge carrier mobility, while the dopant does not alter significantly other electronic characteristics in LCPO. Our results suggest that the overall performance of LCPO as a cathode material for solid-state Li-ion batteries can be improved by reducing the intrinsic defects and using silicon doping.