Single-ion conducting polymer electrolytes(SIPEs)can be formed by anchoring charge delocalized anions on the side chains of a crosslinked polymer matrix,thereby eliminating the severe concentration polarization efect ...Single-ion conducting polymer electrolytes(SIPEs)can be formed by anchoring charge delocalized anions on the side chains of a crosslinked polymer matrix,thereby eliminating the severe concentration polarization efect in conventional dual-ion polymer electrolytes.Addition of a plasticizer into the polymer matrix confers advantages of both liquid and solid electrolytes.However,plasticized SIPEs usually face a trade-of between conductivity and mechanical strength.With insufcient strength,potentially there is short-circuiting failure during cycling.To address this challenge,a simple and mechanicallyrobust SIPE was developed by crosslinking monomer lithium(4-styrenesulfonyl)(trifuoromethylsulfonyl)imide(LiSTFSI)and crosslinker poly(ethylene glycol)diacrylate(PEGDA),with plasticizer propylene carbonate(PC),on electrospun polyacrylonitrile nanofbers(PAN-NFs).The well-fabricated polymer matrix provided fast and efective Li^(+) conductive pathways with a remarkable ionic conductivity of 8.09×10^(-4) S cm^(−1) and a superior lithium-ion transference number close to unity(t_(Li+)=0.92).The introduction of PAN-NFs not only improved the mechanical strength and fexibility but also endowed the plasticized SIPE with a wide electrochemical stability window(4.9 V vs.Li^(+)/Li)and better cycling stability.Superior longterm lithium cycling stability and dynamic interfacial compatibility were demonstrated by lithium symmetric cell testing.Most importantly,the assembled all-solid-state Li metal batteries showed stable cycling performance and remarkable rate capability both in low and high current densities.Therefore,this straightforward and mechanically reinforced SIPE exhibits great potential in the development of advanced all-solid-state Li-metal batteries.展开更多
基金This work was supported by the Samuel S.Walker Distinguished Professorship in the Wilson College of Textiles at North Carolina State University。
文摘Single-ion conducting polymer electrolytes(SIPEs)can be formed by anchoring charge delocalized anions on the side chains of a crosslinked polymer matrix,thereby eliminating the severe concentration polarization efect in conventional dual-ion polymer electrolytes.Addition of a plasticizer into the polymer matrix confers advantages of both liquid and solid electrolytes.However,plasticized SIPEs usually face a trade-of between conductivity and mechanical strength.With insufcient strength,potentially there is short-circuiting failure during cycling.To address this challenge,a simple and mechanicallyrobust SIPE was developed by crosslinking monomer lithium(4-styrenesulfonyl)(trifuoromethylsulfonyl)imide(LiSTFSI)and crosslinker poly(ethylene glycol)diacrylate(PEGDA),with plasticizer propylene carbonate(PC),on electrospun polyacrylonitrile nanofbers(PAN-NFs).The well-fabricated polymer matrix provided fast and efective Li^(+) conductive pathways with a remarkable ionic conductivity of 8.09×10^(-4) S cm^(−1) and a superior lithium-ion transference number close to unity(t_(Li+)=0.92).The introduction of PAN-NFs not only improved the mechanical strength and fexibility but also endowed the plasticized SIPE with a wide electrochemical stability window(4.9 V vs.Li^(+)/Li)and better cycling stability.Superior longterm lithium cycling stability and dynamic interfacial compatibility were demonstrated by lithium symmetric cell testing.Most importantly,the assembled all-solid-state Li metal batteries showed stable cycling performance and remarkable rate capability both in low and high current densities.Therefore,this straightforward and mechanically reinforced SIPE exhibits great potential in the development of advanced all-solid-state Li-metal batteries.
