Constructing dual silsesquioxane-crosslinked network channels in hybrid polymer membranes for dendrite-free and durable high-power LMBs

Abstract

The practical implementation of high-energy-density lithium metal batteries remains a challenging task due to the instability of conventional solid electrolyte interphase (SEI) layers. To satisfy interfacial performance and ionic conductivities of non-dendritic lithium electrodeposition, battery membranes can be considered a paradigm shift for lithium anode protection. Here, we present an effective membrane engineering strategy that leverages the integrated structure of dual silsesquioxane-crosslinked polymer networks on nanofibers for in situ controlled manipulation of SEI chemistry. The functional hybrid polymer membranes (FHMs), which feature a hierarchical porous architecture, an abundance of lipophilic groups, and a high modulus, exhibit high Li-ion conductivity (∼2.56 mS cm⁻¹), near-single ion conduction (∼0.93), and remarkable electrochemical stability over 5.7 V. Furthermore, the FHM-based cells displayed an impressive coulombic efficiency of over 91% in Cu‖Li cells at 10 mA cm⁻², remarkable cyclability exceeding 2200 h in Li‖Li symmetric cells, and noteworthy capacity retention (∼83%) after 200 cycles at an ultra-high 10C rate. This study offers valuable insights from the perspective of polymer electrolyte engineering to form robust non-dendritic lithium-supported SEIs and achieve durable application of high-performance batteries.