High-Performance Zn-TiC-C Nanocomposite Alloy Anode with Exceptional Cycle Life for Lithium-Ion Batteries.

A Zn-based nanocomposite has been prepared through a facile, low-cost high-energy mechanochemical process and employed as an anode material for lithium-ion batteries. Structural characterization reveals that the micrometer-sized Zn-TiC-C nanocomposite is composed of Zn nanocrystals uniformly dispersed in a multifunctional TiC and conductive carbon matrix with a tap density of 1.3 g cm(-3). The Zn-TiC-C nanocomposite exhibits high reversible volumetric capacity (468 mA h cm(-3)), excellent cyclability over 800 cycles (79.2% retention), and good rate performance up to 12.5C (75% of its capacity at 0.25C rate). The enhanced electrochemical performance is mainly due to the presence of the well-mixed TiC+C matrix that plays an important role in providing high conductivity as well as mechanical buffer that mitigates the huge volume expansion and contraction during prolonged cycling. In addition, it prevents the particle growth by uniformly dispersing nanosized Zn within itself during cycling, maintaining high utilization (∼100%) and fast reaction kinetics of Zn anode.