Breaking the capacity bottleneck of lithium-oxygen batteries through reconceptualizing transport and nucleation kinetics

Author：Zhang, Z. J., Xiao, X., Yan, A. J., Sun, K., Yu, J. W., Tan, P.

Journal：Nature Communications

DOI:  10.1038/s41467-024-54366-z

Keywords: cathode microstructure, electron-microscopy, li-o-2 battery, discharge, strategies, criteria, growth, scale, Science & Technology - Other Topics

Abstract: 

The practical capacity of lithium-oxygen batteries falls short of their ultra-high theoretical value. Unfortunately, the fundamental understanding and enhanced design remain lacking, as the issue is complicated by the coupling processes between Li2O2 nucleation, growth, and multi-species transport. Herein, we redefine the relationship between the microscale Li2O2 behaviors and the macroscopic electrochemical performance, emphasizing the importance of the inherent modulating ability of Li+ ions through a synergy of visualization techniques and cross-scale quantification. We find that Li2O2 particle distributed against the oxygen gradient signifies a compatibility match for the nucleation and transport kinetics, thus enabling the output of the electrode's maximum capacity and providing a basis for evaluating operating protocols for future applications. In this case, a 150% capacity enhancement is further achieved through the development of a universalizing methodology. This work opens the door for the rules and control of energy conversion in metal-air batteries, greatly accelerating their path to commercialization. To realize the theoretical energy density of lithium-oxygen batteries, this work uses the relationship between microscopic phenomena and macroscopic performance. By adjusting lithium-ion concentration, alignment of transport and nucleation kinetics improves and discharge capacity of the electrodes maximized.