The commercialization of lithium-sulfur(Li-S)batteries faces several challenges,including poor conductivity,unexpected volume expansion,and continuous sulfur loss from the cathode due to redox shuttling.In this study,...The commercialization of lithium-sulfur(Li-S)batteries faces several challenges,including poor conductivity,unexpected volume expansion,and continuous sulfur loss from the cathode due to redox shuttling.In this study,we introduce a novel polymer via a simple cross-linking between poly(ether-thioureas)(PETU)and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)(PEDOT:PSS)as a bifunctio nal binder for Li-S batteries(devotes as"PPTU").Compared to polyvinylidene fluoride(PVDF),as-prepared PPTU exhibits significantly higher electrical conductivity,facilitating electrochemical reactions.Additionally,PPTU demonstrates effective adsorption of lithium polysulfides,leading to improved cycling stability by suppressing the shuttling effect.We investigate this behavior by monitoring morphological changes at the cell interface using synchrotron X-ray tomography.Cells with PPTU binders exhibit remarkable rate performance,desired reversibility,and excellent cycling stability even under stringent bending and twisting conditions.Our work represents promising progress in functional polymer binder development for Li-S batteries.展开更多
Although lithium iodide(LiI)as a redox mediator(RM)can decrease the overpotential in Li-O_(2)batteries,the stability of the Li anode is still one critical issue due to the redox shuttling.Here,we firstly present a nov...Although lithium iodide(LiI)as a redox mediator(RM)can decrease the overpotential in Li-O_(2)batteries,the stability of the Li anode is still one critical issue due to the redox shuttling.Here,we firstly present a novel approach for generating Ag and LiTFSI enriched Li anode(designated as ALE@Li anode)via a spontaneous substitution between pure Li and bis(trifluoromethanesulfonyl)imide silver,in a LiI-participated Li-O_(2)cell.It can induce the generation of a lithiophilic solid electrolyte interphase(SEI)enriched with Ag,F,and N species(e.g.,Ag_(2)O,Li-Ag alloy,LiF,and Li_(3)N)during cell operation,which contributes to promoting the electrochemical performance through the shuttling inhibition.Compared to a cell with a bare Li anode,the one with as-prepared ALE@Li anode shows an enhanced cyclability,a considerable rate capability,and a good reversibility.In addition,a synchrotron X-ray computed tomography technique is employed to investigate the inhibition mechanism for shuttling effect by monitoring the morphological evolution on the cell interfaces.Therefore,this work highlights the deliberate design in the modified Li anode in an easy-to-operate and cost-effective way as well as providing guidance for the construction of artificial SEI layers to suppress the redox shuttling of RMs in Li-O_(2)batteries.展开更多
基金supported by the Science and Technology Project of Jilin Provincial Education Department (JJKH20221160KJ)the Jilin Province Science and Technology Department (20230402059GH)the National Natural Science Foundation of China (22279014)。
文摘The commercialization of lithium-sulfur(Li-S)batteries faces several challenges,including poor conductivity,unexpected volume expansion,and continuous sulfur loss from the cathode due to redox shuttling.In this study,we introduce a novel polymer via a simple cross-linking between poly(ether-thioureas)(PETU)and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)(PEDOT:PSS)as a bifunctio nal binder for Li-S batteries(devotes as"PPTU").Compared to polyvinylidene fluoride(PVDF),as-prepared PPTU exhibits significantly higher electrical conductivity,facilitating electrochemical reactions.Additionally,PPTU demonstrates effective adsorption of lithium polysulfides,leading to improved cycling stability by suppressing the shuttling effect.We investigate this behavior by monitoring morphological changes at the cell interface using synchrotron X-ray tomography.Cells with PPTU binders exhibit remarkable rate performance,desired reversibility,and excellent cycling stability even under stringent bending and twisting conditions.Our work represents promising progress in functional polymer binder development for Li-S batteries.
基金supported by Science and Technology Project of Jilin Provincial Education Department(grant no.JJKH20221160KJ)Jilin Province Science and Technology Department(grant no.20230402059GH)+1 种基金The Swedish Foundation for International Cooperation in Research and Higher Education(grant no.KO2017-7351)Swedish Energy Agency(Project no.P2020-90216).
文摘Although lithium iodide(LiI)as a redox mediator(RM)can decrease the overpotential in Li-O_(2)batteries,the stability of the Li anode is still one critical issue due to the redox shuttling.Here,we firstly present a novel approach for generating Ag and LiTFSI enriched Li anode(designated as ALE@Li anode)via a spontaneous substitution between pure Li and bis(trifluoromethanesulfonyl)imide silver,in a LiI-participated Li-O_(2)cell.It can induce the generation of a lithiophilic solid electrolyte interphase(SEI)enriched with Ag,F,and N species(e.g.,Ag_(2)O,Li-Ag alloy,LiF,and Li_(3)N)during cell operation,which contributes to promoting the electrochemical performance through the shuttling inhibition.Compared to a cell with a bare Li anode,the one with as-prepared ALE@Li anode shows an enhanced cyclability,a considerable rate capability,and a good reversibility.In addition,a synchrotron X-ray computed tomography technique is employed to investigate the inhibition mechanism for shuttling effect by monitoring the morphological evolution on the cell interfaces.Therefore,this work highlights the deliberate design in the modified Li anode in an easy-to-operate and cost-effective way as well as providing guidance for the construction of artificial SEI layers to suppress the redox shuttling of RMs in Li-O_(2)batteries.
