Advances in Air-Stable Silicon-Based Anodes and Their Application in Li–Air Batteries

In recent years, silicon-based anodes have become a model of commercial success among various high-capacity electrode materials. They also offer a promising substitute for the lithium metal anode (LMA) in lithium–air batteries (LABs), which have the highest specific energy. However, the poor air stability of lithiated silicon-based anodes makes pre-lithiation considerably more difficult and costly in mass production to improve their initial Coulombic efficiency and cyclability, which complicates their material design and electrode manufacturing. To address this issue, intensified efforts have been devoted in recent years, mainly by constructing encapsulation structures, such as core–shell, pomegranate-like or peapod-like architectures. These designs have achieved significantly boosted stability in dry air and, in some cases, even under prolonged exposure to ambient humidity. On the other hand, it was found that silicon-based anodes often provide better cyclic stability than LMAs in LABs and lithium–oxygen batteries (LOBs); however, in most cases, the silicon-based anodes were not optimized for air stability. This review summarizes the relevant works on improving the air stability of silicon-based anodes and LABs/LOBs that used a silicon-based anode, intending to shed light on future development of air-stable silicon-based anodes and bridge the gap between the electrodes’ air-stability and their application in LABs/LOBs.