The Exploration of Li + Transfer Kinetics Mechanism under the Dielectric Effect in Lithium Metal Anode: Unilateral and Bilateral Electrode Protection

Artificial protection layers (APLs) are an effective strategy to protect lithium metal anodes. Current research primarily focuses on applying APLs to the electrode surface where lithium deposition occurs. However, limited attention has been given to how adding APLs to the counter electrode surface impacts the performance of lithium metal batteries. In this study, we combine experimental and simulation approaches to investigate the effects of applying APLs either solely on the lithium deposition side or on both electrodes of the battery. Experimental results show that Li-LFP batteries cycled at 2 C without APLs exhibited a capacity retention below 80% after 245 cycles. When APLs were applied only to the lithium deposition side, the batteries could cycle for 464 cycles. Remarkably, when APLs were applied to both electrodes, the Li-LFP batteries retained over 80% capacity retention even after 800 cycles. These findings indicate that applying APLs to both the lithium deposition side and the counter electrode significantly enhances the electrochemical performance of the battery. This study breaks the current paradigm of focusing solely on the lithium metal electrode surface, providing valuable insights for the development of safer and higher-performance lithium metal anode battery systems in the future.