Quasi-solid-state composite electrolytes(QSCEs)show promise for high-performance solid-state batteries,while they still struggle with interfacial stability and cycling performance.Herein,a F-grafted QSCE(F-QSCE)was de...Quasi-solid-state composite electrolytes(QSCEs)show promise for high-performance solid-state batteries,while they still struggle with interfacial stability and cycling performance.Herein,a F-grafted QSCE(F-QSCE)was developed via copolymerizing the F monomers and ionic liquid monomers.The F-QSCE demonstrates better overall performance,such as high ionic conductivity of 1.21 mS cm^(-1)at 25℃,wide electrochemical windows of 5.20 V,and stable cycling stability for Li//Li symmetric cells over 4000 h.This is attributed to the significant electronegativity difference between C and F in the fluorinated chain(-CF_(2)-CF-CF_(3)),which causes the electron cloud to shift toward the F atom,surrounding it with a negative charge and producing the inductive effect.Furthermore,the interactions between Li^(+)and F,TFSI~-,and C are enhanced,reducing ion pair aggregation(Li^(+)-TFSI~--Li^(+))and promoting Li^(+)transport.Besides,-CF_(2)-CF-CF_(3)decomposes to form Li F preferentially over TFSI~-,resulting in better interfacial stability for F-QSCE.This work provides a pathway to enable the development of high-performance Li metal batteries.展开更多
基金conducted in a project within M-ERA.NET 3 with support from the European Union’s Horizon 2020 research,innovation program under grant agreement No.958174,Vinnova(Swedish Governmental Agency for Innovation Systems)the financial support from the LTU CREATERNITY program+1 种基金the J.Gust Richert Foundationthe National Natural Science Foundation of China(No.U23A20122)。
文摘Quasi-solid-state composite electrolytes(QSCEs)show promise for high-performance solid-state batteries,while they still struggle with interfacial stability and cycling performance.Herein,a F-grafted QSCE(F-QSCE)was developed via copolymerizing the F monomers and ionic liquid monomers.The F-QSCE demonstrates better overall performance,such as high ionic conductivity of 1.21 mS cm^(-1)at 25℃,wide electrochemical windows of 5.20 V,and stable cycling stability for Li//Li symmetric cells over 4000 h.This is attributed to the significant electronegativity difference between C and F in the fluorinated chain(-CF_(2)-CF-CF_(3)),which causes the electron cloud to shift toward the F atom,surrounding it with a negative charge and producing the inductive effect.Furthermore,the interactions between Li^(+)and F,TFSI~-,and C are enhanced,reducing ion pair aggregation(Li^(+)-TFSI~--Li^(+))and promoting Li^(+)transport.Besides,-CF_(2)-CF-CF_(3)decomposes to form Li F preferentially over TFSI~-,resulting in better interfacial stability for F-QSCE.This work provides a pathway to enable the development of high-performance Li metal batteries.
