Abstract:Aqueous zinc-ion batteries have become one of the best choices for the next generation of large-scale energy storage systems due to their abundant raw materials, excellent safety performance and low cost. However, due to the side reactions of zinc metal anode and the growth of dendrites, the cycle stability of zinc anode is poor, which reduces its material utilization rate and coulomb efficiency, and causes a series of safety problems, thereby restricting its commercial development. Therefore, it is necessary to find a reliable zinc anode modification method to overcome the above shortcomings. In this paper, chitosan was added as an electrolyte additive to the prepared zinc sulfate electrolyte to slow down the side reaction of zinc anode and inhibit the formation of dendrites. The results showed that the stable cycle of zinc anode could be extended by 600 weeks when the concentration of chitosan electrolyte additive was 0.5 mg/mL. In addition, when Zn-V2O5 full battery used chitosan-based ZnSO4 electrolyte, it also showed good electrochemical performance. For example, the reversible capacity after 50 cycles was still maintained at 120 mAh/g, which was higher than that of Zn-V2O5 full battery using blank electrolyte. Therefore, the use of chitosan as an electrolyte additive could stabilize Zn anode and greatly improve the cycle performance and service life of zinc-ion batteries.