Mechanistic Insights into the Discharge Processes of Li-CO₂ Batteries

Li-CO₂ batteries facilitate renewable energy storage in a cost-effective, eco-friendly 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, particularly in terms of the theoretical aspect. First, the vital factors affecting the formation of discharge intermediates are highlighted, and a surface lithiation mechanism predominantly applicable to catalysts with weak CO₂ adsorption is proposed. Subsequently, the modeling of the chemical potential of Li⁺+e^-, which is crucial for the evaluation of the theoretical limiting voltage, is detailed. Finally, challenges and future directions pertaining to the further development of Li-CO₂ are discussed. In essence, this concept article seeks to inspire future experimental and theoretical studies in advancing the development of Li-CO₂ electrochemical technology.