Ni0.05Ti1.95Nb10O29: an advanced anode material for high-performance lithium-ion storage

Abstract

Abstract Ti2Nb10O29 (TNO) has garnered significant research attention due to its high specific capacity and excellent safety features, positioning it as a promising anode material for lithium-ion batteries (LIBs). Nevertheless, its rate capability is significantly hampered by poor electronic and ionic conductivity. In this paper, Ni2+ doping has been first applied to address these issues. A series of Ni2+ doped TNO (Nix-TNO (x = 0.03, 0.05, 0.07) electrode materials have been prepared to unveil the effects of Ni2+ content. The experimental results unveil that Ni2+ doping maintains the Wadsley-Roth shear structure of TNO while augmenting the single-cell volume and introducing additional oxygen vacancies in TNO. This generates a wider diffusion path and more active sites for lithium ions (Li+). Besides, the introduction of Ni2+ can alter the conductive field distribution of TNO, giving rise to a much higher electronic conductivity of Nix-TNO. Among the synthesized Nix-TNO, Ni0.05-TNO shows the best electrochemical performance, demonstrating a reversible capacity of 306 mAh g–1 with a Coulombic efficiency of 91.46% in the first cycle at 0.1 C and 146.19 mAh g–1 at 10 C after 500 cycles.