Lithiophilicity: The key to efficient lithium metal anodes for lithium batteries

Lithium metal anode of lithium batteries, including lithium-ion batteries, has been considered the anode for next-generation batteries with desired high energy densities due to its high theoretical specific capacity (3860 mA h g−1) and low standards electrode potential (−3.04 V vs. SHE). However, the highly reactive nature of metallic lithium and its direct contact with the electrolyte could lead to severe chemical reactions, leading to the continuous consumption of the electrolyte and a reduction in the cycle life and Coulombic efficiency. In addition, the solid electrolyte interface formed during battery cycling is mainly inorganic, which is too fragile to withstand the extreme volume change during the plating and stripping of lithium. The uneven flux of lithium ions could lead to excessive lithium deposition at local points, resulting in needle-like lithium dendrites, which could pierce the separator and cause short circuits, battery failure, and safety issues. In the last five years, tremendous efforts have been dedicated to addressing these issues, and the most successful improvements have been related to lithiophilicity optimizations. Thus, this paper comprehensively reviewed the lithiophilicity regulation in lithium metal anode modifications and highlighted the vital effect of lithiophilicity. The remaining challenges faced by the lithiophilicity optimization for lithium metal anodes are discussed with the proposed research directions for overcoming the technical challenges in this subject.