Synergistic effects of microwave irradiation and CeF3 surface coating of lithium titanate for stable, high-capacity, and high-rate lithium-ion batteries

The low theoretical specific capacity and rapid capacity degradation, especially during long cycling, have been the key challenges to the practical application of lithium titanate (Li4Ti5O12) as an anode material for stable, high-energy and high-power density lithium-ion batteries (LIBs). This study reports a novel strategy of the synergy of surface lattice plane engineering by microwave irradiation and CeF3 surface coating to synthesize a high-specific-capacity, high-rate and durable LTO–CeF3–mw anode material for LIBs. The innovative anode material shows outstanding specific capacity, rate capability and long-term cycle stability. It is of interest to note that the LTO–CeF3–mw anode material has a specific capacity of 191.1 mAh g−1 at 175 mA g−1 (1C), which is greater than the theoretical specific capacity of LTO (175 mAh g−1). Furthermore, LTO–CeF3–mw has specific capacities of 168.3 and 119.9 mAh g−1 at 875 mA g−1 (5C) and 1750 mA g−1 (10C), respectively. Remarkably, it shows a specific capacity of 166.5 mAh g−1 after 1000 cycles at 5C and a capacity retention of 98.9%. This notable electrochemical performance of LTO–CeF3–mw is attributed to the synergy of surface lattice plane engineering by microwave irradiation and CeF3 surface coating that transformed the surface lattice plane (111) of LTO to (220) and (310) in LTO–CeF3–mw, resulting in high surface area which significantly improved mass transport. Therefore, the unique structure of the LTO–CeF3–mw anode material is a key development for achieving safe, durable, high-energy and high-power lithium-ion batteries, with potential applications in large-scale energy storage.