关键词: 水系锌离子电池, 枝晶, 山梨醇添加剂, 溶剂化调节, 界面调节

Abstract: The unstable Zn interfaces caused by undesired dendrite and parasitic side reactions greatly hinder the development of aqueous Zn ion batteries. Herein, hydroxy-rich sorbitol was used as an additive to reshape the solvation structure and modulate the zinc interface chemistry. The strong interaction between sorbitol and both water molecules and Zn electrode can reduce the free water activity, optimize the solvation shell of water and Zn²⁺ ions, regulate the formation of local H₂O^-poor environment on the surface of Zn electrode, and effectively inhibit the decomposition of water molecules, thus the thermodynamically stable and highly reversible Zn electrochemistry is obtained. As a result, Zn/Zn symmetric cells with the sorbitol additive realized an excellent cycling life of 2000 h under 1 mA·cm^-2 and 1 mAh·cm^-2 and over 250 h under 5 mA·cm^-2 and 5 mAh·cm^-2. Moreover, the Zn/Cu asymmetric cells with the sorbitol additive achieved a high Coulomb efficiency of 99.6%, obtain elevated performance than that with pure 2 M ZnSO₄ electrolyte. And the constructed Zn/PNDA batteries can be stably discharged for 2300 cycles at 1 A·g^-1 with an excellent capacity retention rate. This result indicates that based-sorbitol addictive electrolytes under 1 M sorbitol successfully elevated reversible zinc electrochemistry.

Key words: aqueous zinc ion batteries, dendrite, sorbitol additive, solvation regulation, interface modulation