Partial Atomic Disordered Ti ₂ Nb ₁₀ O ₂₉ <i> _‐x </i> Induced by Joule Thermal Shock for Superior Lithium‐Ion Storage

Abstract

ABSTRACT Nb 2 O 5 is a promising anode for high‐power lithium‐ion battery, but its relatively dense atomic packing limits Li + migration capacity exertion. Ti 2 Nb 10 O 29 with Wadsley‐Roth phase with more open crystal structure is considered a promising candidate. However, Ti/Nb atoms prefer to form an ordered arrangement to maintain local charge balance, resulting insufficient Li + migration and suppressing high‐rate performance. Herein, defective Ti 2 Nb 10 O 29‐ x anode with partial disordered Ti/Nb arrangement is developed by employing an amorphous precursor combined with Joule thermal shock. The random dispersion of Ti and Nb within the amorphous precursor is maintained to a certain extent during ultra‐fast Joule thermal heating (≈500°C s −1 ) and quenching (≈250°C s −1 ). Compared to traditional Ti 2 Nb 10 O 29 , the Li + diffusion coefficient and electronic conductivity of Ti/Nb‐disordered Ti 2 Nb 10 O 29‐ x are enhanced by tenfold and four orders of magnitude, respectively. As the anode of lithium‐ion batteries, the optimal Ti 2 Nb 10 O 29‐ x shows an ultra‐high capacity of 353 mAh g −1 and an excellent rate capability of 112 mAh g −1 at 150 C, an ultra‐long cycling lifespan of 5000 cycles, and a wide operating temperature range from 80°C to ‐40°C. The performance leap caused by the disordered structure may provide new paradigm for battery materials.