Improved Stability of Zinc Anodes by a Trace Amount of Xylitol

Zn-ion batteries (ZIBs) have great potential in energy storage systems. However, the parasitic side reactions and dendrite growth during the reversible plating/stripping process limit their practical applications. Electrolyte engineering provides an effective solution to these issues. Herein, a trace amount of xylitol (only 2 mM) is used as an additive to the common ZnSO 4 electrolyte. The results show that xylitol can modulate the solvation coordination between Zn 2+ and H 2 O, reducing the number of active H 2 O molecules. Moreover, the xylitol molecule tends to adsorb on the Zn foil more effectively than H 2 O, thus increasing the Zn nucleation overpotential and suppressing the 2D diffusion of Zn 2+ ions. For these reasons, the side reactions and Zn dendrites can be effectively inhibited in the electrolyte with xylitol. The cycling performance of a Zn||Zn symmetric cell, Zn||Cu asymmetric cell and Zn||VO 2 full cell in electrolyte with xylitol was also enhanced compared with the bare ZnSO 4 electrolyte. Therefore, the green and low-cost xylitol is an effective and promising additive to improve the stability of Zn anodes in ZIBs. Graphical Abstract