Advanced Polymer Materials for Protecting Lithium Metal Anodes of Liquid‐State and Solid‐State Lithium Batteries

Abstract Lithium metal batteries (LMBs) are considered as one type of the most promising next‐generation energy storage devices with high‐energy‐density, and stabilizing the lithium metal anodes (LMAs) to overcome LMBs’ safety concerns and performance degradation has attracted extensive attention. Introducing advanced polymer materials into the critical components of LMBs has proven to be an effective and promising approach for stabilizing LMAs toward practical application of LMBs. In addressing the lack of a timely review on the emerging progress of advanced polymer materials in LMBs for stabilizing LMAs, a comprehensive article summarizing the most recent developments of multiscale cellulose materials, including micron cellulose (MC) and nanocellulose (NC), in LMBs is reviewed. First, the basic structures of cellulose, characteristics comparison, and the development history of introducing cellulose into LMBs are presented. Furthermore, the roles of multiscale cellulose materials and functional mechanisms in various components of LMBs for stabilizing LMAs are summarized. A general conclusion and a perspective on the current limitations and future research directions of cellulose‐based stable LMBs are proposed. The aim of this review is not only to summarize the recent progress of multiscale cellulose materials in stabilizing LMAs but also to lighten the pathways for realizing LMBs’ practical application.