Commercial-level sodium metal batteries require electrolytes with high ionic mobility and excellent thermo-mechanical and electrochemical stability.Conventional flammable liquid electrolytes,prone to dendrite growth a...Commercial-level sodium metal batteries require electrolytes with high ionic mobility and excellent thermo-mechanical and electrochemical stability.Conventional flammable liquid electrolytes,prone to dendrite growth and unstable interfacial reactions,rarely perform beyond coin-cell demonstrations.To address these shortcomings,a multifunctional composite quasi-solid polymer electrolyte(QSPE)that incorporates boron nitride(BN)as an engineered filler in a highly conductive polymer blend system has been developed.The optimized formation(15BN QSPE)delivers a room-temperature ionic conductivity of 2.15 m S cm^(-1)and a sodium-ion transference number of 0.80.Molecular dynamics simulations elucidate the coordination environment and show improved transport in the presence of BN.BN is chemically active and bifunctional:boron acts as an electron acceptor,interacting with solvents and macromolecules,while nitrogen coordinates with sodium ions,tailoring the solvation environment and transport pathways to promote efficient ion migration.The 15BN QSPE is self-extinguishing,resists oxidative thermal degradation,and enables stable cycling in symmetric sodium cells for>1400 h at0.5 m A cm^(-2).A Prussian blue full cell achieves>1500 stable cycles at 1C with -99% Coulombic efficiency in coin-cell configuration.A two-layer pouch cell with dual 15BN QSPE layers delivers 600 stable cycles at 0.125C and withstands rigorous mechanical abuse.These results position 15BN QSPE as a scalable,highperformance electrolyte offering enhanced safety and efficiency for next-generation sodium metal batteries.展开更多
基金a seed grant from IIT Delhi(SGNF148)supported by the JST-ERATO Yamauchi Materials SpaceTectonics Project(JPMJER2003)+2 种基金the ARC Australian Laureate Fellowship(FL230100095)the UQ-Yonsei International Joint Research Projectthe support from JSPS Postdoctoral Fellowships for Research in Japan。
文摘Commercial-level sodium metal batteries require electrolytes with high ionic mobility and excellent thermo-mechanical and electrochemical stability.Conventional flammable liquid electrolytes,prone to dendrite growth and unstable interfacial reactions,rarely perform beyond coin-cell demonstrations.To address these shortcomings,a multifunctional composite quasi-solid polymer electrolyte(QSPE)that incorporates boron nitride(BN)as an engineered filler in a highly conductive polymer blend system has been developed.The optimized formation(15BN QSPE)delivers a room-temperature ionic conductivity of 2.15 m S cm^(-1)and a sodium-ion transference number of 0.80.Molecular dynamics simulations elucidate the coordination environment and show improved transport in the presence of BN.BN is chemically active and bifunctional:boron acts as an electron acceptor,interacting with solvents and macromolecules,while nitrogen coordinates with sodium ions,tailoring the solvation environment and transport pathways to promote efficient ion migration.The 15BN QSPE is self-extinguishing,resists oxidative thermal degradation,and enables stable cycling in symmetric sodium cells for>1400 h at0.5 m A cm^(-2).A Prussian blue full cell achieves>1500 stable cycles at 1C with -99% Coulombic efficiency in coin-cell configuration.A two-layer pouch cell with dual 15BN QSPE layers delivers 600 stable cycles at 0.125C and withstands rigorous mechanical abuse.These results position 15BN QSPE as a scalable,highperformance electrolyte offering enhanced safety and efficiency for next-generation sodium metal batteries.
