锌离子凝胶态电解质对锌负极界面稳定化研究  

Stabilization study of hydrogel Zn^(2+) electrolyte on interface of zinc anode

作　　者：程颖博 杨程 杨建华[1] 刘宇[1] CHENG Yingbo;YANG Cheng;YANG Jianhua;LIU Yu(Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai 200050,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院上海硅酸盐研究所,上海200050 [2]中国科学院大学,北京100049

出　　处：《电源技术》2022年第4期425-428,共4页Chinese Journal of Power Sources

摘　　要：通过在水系锌离子电解液中分散气相二氧化硅,设计了一类凝胶态锌离子电解质,在锌电极界面为锌离子沉积提供了均匀的成核位点,有效抑制锌枝晶形成,同时降低锌离子沉积的成核过电势,提高锌电池倍率性能。测试表明制备的凝胶态电解质的电导率为25.31 mS/cm,采用凝胶电解质组装成的锌对称电池在2 mA/cm^(2)电流密度以及2 mAh/cm^(2)面积比容量的条件下,循环100 h未发生短路现象;以金属钛为对电极的半电池库仑效率可达98.25%。进一步基于该电解质,采用锰酸锂为正极、锌为负极组装的全电池,在50 C高倍率下保持52.4 mAh/g的比容量(基于锰酸锂活性材料,1 C=140 mA/g),在10 C下,1000次循环后容量保持率为43.6%。This work developed a hydrogelZn^(2+)electrolyte by dispersing SiO_(2) fumed silica through aqueousZn^(2+)electrolyte.As expected,the formation of dendrite at the interface of Zn electrode could be highly restrained due to homogeneous nucleation sites forZn^(2+)deposition.The rate capability of Zn cell could be improved because of the reduce on the nucleation overpotential forZn^(2+)deposition.The conductivity of the hydrogel electrolyte is 25.31 mS/cm,and the Zn/Zn symmetric cells with the hydrogel electrolyte can keep stable for 100 h under current density of 2 mA/cm^(2)and areal specific capacity of 2 mAh/cm^(2).The Zn/Ti half-cell possesses a high coulombic efficiency of 98.25%.The full cell based on LiMn_(2)O_(4)cathode and Zn possesses a high specific capacity of 52.4 mAh/g at a high rate of 50 C.The capacity retention of the cell after 1000 cycles at a rate of 10 C is still 43.6%.

关 键 词：气相二氧化硅 锌离子凝胶态电解质 锌电极 界面稳定化 

分 类 号：TM912.9[电气工程—电力电子与电力传动]