Preparation, processing, and application of ultrathin lithium metal

Lithium metal is a promising electrode material for next‐generation high‐energy‐density rechargeable batteries with its high theoretical capacity (3860 mAh g−1) and low standard electrode potential (−3.04 V vs. SHE). However, the special physicochemical properties of lithium metal, including low tensile strength, viscoplastic creep, and high reactivity hinder the processing and preparation of lithium strips toward ultrathin thickness (≤20 μm). Developing new matrixes, interfaces, and processing methods can be promising for overcoming these problems. This review summarizes the physicochemical properties of lithium metal and the design principles for preparing the ultrathin Li metal, and concludes the recent development in this field from the perspective of processing design, and proposes to provide in‐depth understanding of reliable fabrication of ultrathin lithium metal strips, and prospects the challenges and opportunities of ultrathin‐scale preparation and processing of lithium metal.