Mechanistic Insights into the Discharge Processes of Li-CO2 Batteries.

Li-CO2 batteries correspond to renewable energy storage in a cost-effective, eco-friendly CO2 fixation manner. However, an inadequate understanding of their reaction mechanism severely impedes their development. Here we outline recent mechanistic advances in the discharge processes of Li-CO2 batteries, especially from the theoretical aspect. We first highlight the vital factors affecting the formation of discharge intermediates and a surface lithiation mechanism that may dominate the catalysts with weak CO2 adsorption. Then, we discuss the modeling of the chemical potential of Li+ + e-, which is crucial for the evaluation of the theoretical limiting voltage. Finally, we describe challenges and future directions to facilitate the understanding of Li-CO2 electrochemistry. This concept article would inspire more experimental and theoretical studies to advance the development of Li-CO2 electrochemical technology.