Li-storage of Li2ZnTi3O8@C-N anodes with high-performance in a wide temperature range.

Spinel Li₂ZnTi₃O₈ (LZTO) with a zero volumetric change, exhibits high safety as an anode of lithium-ion batteries. Nevertheless, the low electrical conductivity restricts its wide application. A facile one-step solid-state route has been used to synthesize LZTO@C-N composites with different N content. The existence of N-doped carbon improves the diffusion coefficients of Li⁺ ions and the electronic conductivity, and reduces the charge-transfer resistance and the side reactions between electrolyte and LZTO. The N content can affect the lattice constants and the appearance the new phases. The LZTO@C-N-2 composite with the proper N content of 2.2 w.% possesses the best electrochemical performance in wide temperature range from 0 to 55 °C. Discharging at 2 A g⁻¹ and charging at 0.5 A g⁻¹, 219.7 and 214.8 mAh g⁻¹ are obtained for LZTO@C-N-2 at the 1st and 150th cycles, respectively, with small capacity fade at 25 °C. 290.3 and 151 mAh g⁻¹ are delivered at the 1st and 150th cycles for LZTO@C-N-2 at 55 °C, respectively. Even at 0 °C, the LZTO@C-N-2 composite still shows good rate capability. The simple synthetic route and good electrochemical performance enable LZTO@C-N-2 to be a potential anode of LIBs. [ABSTRACT FROM AUTHOR]