Residual stress-tailored lithium deposition and dissolution behaviors for safe lithium metal anode

Abstract

The commercial applications of lithium metal anode (LMA) have been severely hindered due to the capacity fading and safety hazards caused by Li dendrites. The formation of dendrites is attributed to the electrode/electrolyte interface degradation resulted from the electrodeposition-induced stress. Herein, we take advantage of a facile mechanical-pressing method to build the residual stress field in Li surface to neutralize the deposition stress and construct the insulated polygonal array using the broken native film fragments to redistribute electric field. It is found that the preferential plating/stripping of Li at the edge of the debris due to the synergistic effects of residual stress field and the insulated polygonal array. Therefore, the mechanical-pressed Li (MPLi) exhibits excellent electrochemical performance in symmetric cell and half-type cell when paired with LiFePO4 (LFP). The method for constructing residual stress field and insulated polygonal array through compressing provides new ideas for the development of the stress-related regulation strategies on LMA.