Advances in silane-bridging engineering for stable lithium metal batteries

Lithium metal batteries (LMBs) using metallic lithium have garnered considerable attention as a prominent battery technology with high energy density. Nonetheless, the commercialization of LMBs has been hindered by rapid capacity decay and potential safety risks. These impediments stem from challenges during cycling processes, including unstable solid electrolyte interface (SEI) layer and uncontrollable lithium dendrites growth. To tackle the above-mentioned issues, silane coupling agents (SCAs), which contain both organic functional groups and alkoxy groups, have emerged as one of the preferred pivotal materials for enhancing LMBs performance, and is seen as a popular interface adhesion promoter. Specifically, by incorporating various SCAs into the artificial SEI layer, the liquid electrolyte, the separator, and the solid-state composite electrolyte, stable long-term cycling of LMBs has been achieved. This review comprehensively summarizes and discusses the latest advancements in the design and application of SCAs into LMBs, aiming to reveal both the structure-function relationship and the key role in optimizing the performance of LMBs. Moreover, existing challenges and future prospects for the expanded utilization of SCAs in LMBs are provided. Ultimately, the authors envisage that this review can provide theoretical guidance for the design of multifunctional SCAs, and inspire researchers to further explore the potential of SCAs applied to energy storage systems.