Improving Li reversibility in Li metal batteries through uniform dispersion of Ag nanoparticles on graphene
Yu Gao, Bingfeng Cui, Jiajun Wang, Zhao‐Yong Sun, Qiang Chen, Yida Deng, Xiaopeng Han, Wenbin Hu
Abstract
Abstract Li metal is the most attractive and promising anode material for next‐generation high‐energy batteries. However, uncontrolled Li dendrite growth during cycling remains a highly challenging drawback. To solve this problem, silver‐coated graphene (Ag/GH) was prepared via a simple liquid‐phase reduction method. The effect of Ag/GH on Li deposition behavior was investigated by adjusting the dispersion of Ag nanoparticles (Ag NPs). Subsequently, a composite electrode was fabricated via uniform deposition of metallic Li on Ag/GH. Ag was used as a lithiophilic nucleating agent to ensure uniform deposition of Li and inhibit the growth of Li dendrites on the anode. The prepared composite anode showed a significantly improved performance compared to the unmodified electrode. The symmetric cell comprising this composite electrode exhibited a stable cycling performance with a low hysteresis of ~ 40 mV and a lifetime of > 2000 h at a current density of 0.5 mA·cm −2 . Meanwhile, the discharge capacity reached 0.5 mAh·cm −2 . In addition, Ag/GH was found to be amenable to large‐scale synthesis. Thus, the composite Ag/GH anode exhibited improved performance and the preparation method showed significant potential for application in the manufacture of Li metal batteries.