TiFeNb 10 O 29- δ anode for high-power and durable lithium-ion batteries.

A new Fe-substituted TiFeNb 10 O 29- δ (TFNO) anode is proposed. TFNO possesses a defective and polycrystalline ReO 3 Roth-Wadsley shear structure with a slightly larger lattice volume. Electrochemical behavior results and density functional theory (DFT) calculations show that TFNO can facilitate the kinetics of electron/Li + transportation and demonstrates pseudocapacitive behavior. Consequently, TFNO exhibits superior high rate capacity and cycling stability compared to pristine TNO, offering 100 mA h g -1 at an ultrahigh rate of 50C and a high capacity retention of 86.7% over 1000 cycles at 10C. This work reveals that TFNO could be a promising anode material for fast-charging, stable, and safe LIBs.