Lithium lanthanum titanate perovskite as an anode for lithium ion batteries.

Conventional lithium-ion batteries embrace graphite anodes which operate at potential as low as metallic lithium, subjected to poor rate capability and safety issues. Among possible alternatives, oxides based on titanium redox couple, such as spinel Li4Ti5O12, have received renewed attention. Here we further expand the horizon to include a perovskite structured titanate La0.5Li0.5TiO3 into this promising family of anode materials. With average potential of around 1.0 V vs. Li+/Li, this anode exhibits high specific capacity of 225 mA h g-1 and sustains 3000 cycles involving a reversible phase transition. Without decrease the particle size from micro to nano scale, its rate performance has exceeded the nanostructured Li4Ti5O12. Further characterizations and calculations reveal that pseudocapacitance dictates the lithium storage process and the favorable ion and electronic transport is responsible for the rate enhancement. Our findings provide fresh impetus to the identification and development of titanium-based anode materials with desired electrochemical properties.