Search for stable host materials as low-voltage anodes for lithium-ion batteries: A mini-review

The explosive demand for lithium-ion batteries (LIBs) in electric vehicles, portable electronics, and smart grids has spurred extensive research in recent years. The key to essential advances in LIBs depends on the search for stable host electrode materials with desirable energy and power densities. In the development of emerging stable host anode materials, the operating potential is an overlooked but crucial parameter because it deeply influences the energy, power, and safety of batteries. The ideal potential should not be too close to the lithium deposition potential like graphite (0.1 V vs. Li+/Li) which would trigger the formation of lithium dendrites under high rates, nor should be too high like spinel Li4Ti5O12 (> 1.5 V vs. Li+/Li) which compromises the batteries' power and energy density. This mini-review firstly gives an account of several types of titanium-based and vanadium-based compounds as stable host anodes with the average operating potentials around or below 1 V vs. Li+/Li. The mechanisms for stable lithium storage and the origins of the low operating potentials are discussed by combining various characterization technologies. The key barriers and corresponding approaches are summarized for progressive electrochemical performance. Furthermore, several concise perspectives and challenges aiming at further theoretical prediction and practical application are provided.