Synthesis and properties of nickel-doped Li₄Ti₅O₁₂/C nano-composite: an anode for lithium ion batteries

Composite of nickel-doped Li₄Ti₅O₁₂ and carbon (designated as Ni–Li₄Ti₅O₁₂/C) is synthesized by solid-state reaction with sucrose added as the conductive carbon source. For comparison, nickel-doped Li₄Ti₅O₁₂ (designated as Ni–Li₄Ti₅O₁₂) is obtained under similar conditions. Both materials are characterized by x-ray diffraction, scanning electron microscopy, energy-dispersive x-ray spectroscopy, charge–discharge cycling and cyclic voltammetry. Analysis of SEM images shows that Ni–Li₄Ti₅O₁₂/C consists of smaller particles than Ni–Li₄Ti₅O₁₂. Charge/discharge cycling as well as cyclic voltammetry studies prove that Ni–Li₄Ti₅O₁₂/C electrodes perform much better than those made from Ni–Li₄Ti₅O₁₂. The specific capacities of the Ni–Li₄Ti₅O₁₂/C composite are close to the theoretical capacity of Li₄Ti₅O₁₂ even at high current rates—the discharge capacity of Ni–Li₄Ti₅O₁₂/C at 2C is equal to 164 mA h g⁻¹. (paper)