Anode Interface Engineering and Architecture Design for High-Performance Lithium-Sulfur Batteries

Abstract

Lithium-sulfur (Li-S) batteries are considered as one of the most promising options to realize rechargeable batteries with high energy capacity. Previously, research has mainly focused on solving the polysulfides' shuttle, cathode volume changes, and sulfur conductivity problems. However, the instability of anodes in Li-S batteries has become a bottleneck to achieving high performance. Herein, the main efforts to develop highly stable anodes for Li-S batteries, mainly including lithium metal anodes, carbon-based anodes, and alloy-based anodes, are considered. Based on these anodes, their interfacial engineering and structure design are identified as the two most important directions to achieve ideal anodes. Because of high reactivity and large volume change during cycling, Li anodes suffer from severe side reactions and structure collapse. The solid electrolyte interphase formed in situ by modified electrolytes and ex situ artificial coating layers can enhance the interfacial stability of anodes. Replacing common Li foil with rationally designed anodes not only suppresses the formation of dendritic Li but also delays the failure of Li anodes. Manipulating the anode interface engineering and rationally designing anode architecture represents an attractive path to develop high-performance Li-S batteries.

Keywords: Li metal anodes; Li-metal-free anodes; anodes; lithium-sulfur batteries; solid electrolyte interface.