Copper Zinc Tin Sulfide Anode Materials for Lithium-Ion Batteries at Low Temperature

Developing novel materials is crucial to overcoming the performance degradation of lithium-ion batteries (LIBs) for low-temperature applications. In this work, we demonstrate a novel copper zinc tin sulfide (Cu2ZnSnS4, CZTS) thin film with nanowalls structure as the anode material in thin-film LIBs for low-temperature applications. The quaternary CZTS synthesized by a simple hydrothermal method shows a higher reversible capacity of 475 mAh g-1 after 200 cycles at -10 °C with the EC/DEC/DMC-based electrolyte in comparison with the graphite electrode (110 mAh g-1 after 100 cycles at -10 °C). The effects of temperature and electrolyte systems including EC/DEC- and EC/DEC/DMC-based electrolytes on the cycling performance are studied. The faster Li-ion transport in the electrolyte-electrode interface of the CZTS anode material is obtained in the EC/DEC/DMC-based electrolyte at -10 °C. In addition, the depth-profiling XPS results of the CZTS anode reveal that a solid electrolyte interphase (SEI) layer with less carbon content is formed in the EC/DEC/DMC-based electrolyte likely associated with the interfacial stability at low temperature. The enhanced cycling performance of CZTS could be attributed to its improved interfacial stability and Li+ diffusion, along with the formation of an interconnected active material architecture at low temperature.