2, University of California, Los Angeles, Los Angeles, California, United States
Lithium metal anode has become one of the most promising candidates for energy storage system due to the highest theoretical specific capacity and lowest electrochemical potential. Although substantial progress has been made in recent years, unstable behavior of lithium plating and stripping still prevents its successful transformation to commercialization. To address this issue, robust and conformal coatings directly on lithium surface by vapor deposition under ambient condition were designed and constructed. The resulted coatings not only possess hard inorganic moiety to block the growth of dendrites and soft organic moiety to improve the robustness, but also move dynamically with lithium surface regardless of the infinite volumetric change of lithium metal anodes. As examples, the coated lithium metal anodes were assembled with lithium ion phosphate and sulfur cathodes into rechargeable batteries. These batteries demonstrated double cycling lifetime, as well as dramatically decreased capacity degradation rates, as compared with batteries with pristine lithium anodes. Such a simple approach opens an avenue to stabilize lithium metal anodes for high performance rechargeable lithium metal batteries.