Toward safer lithium metal batteries: a review

Abstract

The energy density of conventional graphite anode batteries is insufficient to meet the requirement for portable devices, electric cars, and smart grids. As a result, researchers have diverted to lithium metal anode batteries. Lithium metal has a theoretical specific capacity (3,860 mAh·g-1) significantly higher than that of graphite. Additionally, it has a lower redox potential of -3.04 V compared to standard hydrogen electrodes. These properties make high-energy lithium metal batteries a promising candidate for next-generation energy storage devices, which have garnered significant interest for several years. However, the high activity of lithium metal anodes poses safety risks (e.g., short circuits and thermal runaway) that hinder their commercial growth. Currently, modification of reversible lithium anodes is the primary focus of lithium metal batteries. This article presents conceptual models and numerical simulations that address failure processes and offer specific techniques to mitigate the challenges of lithium metal anodes, including electrolyte design, interface engineering, and electrode modification. It is expected that lithium metal batteries will recover and become a feasible energy storage solution.