Tortuosity Modulation toward High‐Energy and High‐Power Lithium Metal Batteries

Abstract Lithium metal batteries (LMBs) are well recognized as potentially high‐energy systems to power portable electronics and electric vehicles. However, LMBs always undergo uncontrollable lithium deposition in metallic lithium anodes due to inhomogeneous lithium ion flux, which causes limited power output and impedes their practical applications. Low‐tortuous arrays in metallic lithium anodes have been intensively investigated to guide the fast transport of lithium ions and homogeneous growth of metallic lithium, thereby achieving high‐power LMBs. In this review, the correlation between the electrochemical kinetics and tortuosity of LMBs is first disclosed, especially in the metallic lithium anodes. Subsequently, the material design strategies for the low‐tortuous anodes are systematically summarized, including regulating lithium‐ion flux, electric field, and lithium nucleation by low‐tortuous insulating, conductive, and lithiophilic arrays, respectively. At the same time, low‐tortuous arrays are also efficient in guiding ion transport in the cathodes and solid composite electrolytes of LMBs. Finally, the currently existing challenges of modulating low‐tortuous structures to achieve high‐energy and high‐power LMBs are discussed.