Critical review on recently developed lithium and non-lithium anode-based solid-state lithium-ion batteries

The potential for lithium-ion solid-state battery (SSB) is of interest due to its high energy density, superior mechanical and thermal stability, and inherent safety. Currently, the majority of SSBs use lithium metal (Li) as the anode because of its high theoretical capacity, low density, and low potential. Nonetheless, Li is highly reactive, easily oxidized, and less abundant than potential alternatives. Additionally, Li dendrite formation has been observed even through some solid electrolytes (SE), compromising the battery's safety. Thus, alternative anodes such as Si, Sn, and Ti are under investigation. Among them, Si is a competitive candidate due to its high capacity, reduced dendrite formation and interphase growth when used with SE. Moreover, this material is stable in air, non-reactive, abundant, and cheap. As Si's significant pulverization remains an issue, several improvements are discussed here. Overall, this work analyzes state-of-the-art SSBs with lithium and non-lithium anodes; additional discussion provides an understanding of current gaps in the field along with proposed paths forward. Relatively few articles discuss anode materials for SSBs; thus, we provide a unique analysis of published candidates and their performance. Major points are conveyed in tabular and schematic representations, followed by outlook and recommendations for SSB anode research.