Emerging natural clay-based materials for stable and dendrite-free lithium metal anodes: A review

Lithium metal is one of the most promising anodes for lithium batteries because of their high theoretical specific capacity and the low electrochemical potential. However, the commercialization of lithium metal anodes (LMAs) is facing significant obstacles, such as uncontrolled lithium dendrite growth and unstable solid electrolyte interface, leading to inferior Coulombic efficiency, unsatisfactory cycling stability and even serious safety issues. Introducing low-cost natural clay-based materials (NCBMs) in LMAs is deemed as one of the most effective methods to solve aforementioned issues. These NCBMs have received considerable attention for stabilizing LMAs due to their unique structure, large specific surface areas, abundant surface groups, high mechanical strength, excellent thermal stability, and environmental friendliness. Considering the rapidly growing research enthusiasm for this topic in the last several years, here, we review the recent progress on the application of NCBMs in stable and dendrite-free LMAs. The different structures and modification methods of natural clays are first summarized. In addition, the relationship between their modification methods and nano/microstructures, as well as their impact on the electrochemical properties of LMAs are systematically discussed. Finally, the current challenges and opportunities for application of NCBMs in stable LMAs are also proposed to facilitate their further development.