Silicon(Si)is a competitive anode material owing to its high theoretical capacity and low electrochemical potential.Recently,the prospect of Si anodes in solid-state batteries(SSBs)has been proposed due to less solid ...Silicon(Si)is a competitive anode material owing to its high theoretical capacity and low electrochemical potential.Recently,the prospect of Si anodes in solid-state batteries(SSBs)has been proposed due to less solid electrolyte interphase(SEI)formation and particle pulverization.However,major challenges arise for Si anodes in SSBs at elevated temperatures.In this work,the failure mechanisms of Si-Li_(6)PS_(5)Cl(LPSC)composite anodes above 80℃are thoroughly investigated from the perspectives of interface stability and(electro)chemo-mechanical effect.The chemistry and growth kinetics of Lix Si|LPSC interphase are demonstrated by combining electrochemical,chemical and computational characterizations.Si and/or Si–P compound formed at Lix Si|LPSC interface prove to be detrimental to interface stability at high temperatures.On the other hand,excessive volume expansion and local stress caused by Si lithiation at high temperatures damage the mechanical structure of Si-LPSC composite anodes.This work elucidates the behavior and failure mechanisms of Si-based anodes in SSBs at high temperatures and provides insights into upgrading Si-based anodes for application in SSBs.展开更多
Compared to commercial lithium-ion batteries, all-solid-state batteries can greatly increase the energy density, safety, and cycle life of batteries. The development of solid-state electrolyte with high lithium-ion co...Compared to commercial lithium-ion batteries, all-solid-state batteries can greatly increase the energy density, safety, and cycle life of batteries. The development of solid-state electrolyte with high lithium-ion conductivity and wide electrochemical window is the key for all-solid-state batteries. In this work, we report on the achievement of high ionic conductivity in the PAN/LiClO_(4)/BaTiO_(3) composite solid electrolyte (CSE) prepared by solution casting method. Our experimental results show that the PAN-based composite polymer electrolyte with 5 wt% BaTiO_(3) possesses a high room-temperature lithium-ion conductivity (9.85 × 10^(−4) S⋅cm^(−1)), high lithium-ion transfer number (0.63), wide electrochemical window (4.9 V vs Li+/Li). The Li|Li symmetric battery assembled with 5 wt% BaTiO_(3) can be stably circulated for 800 h at 0.1 mA⋅cm^(−2), and the LiFePO_(4)|CSE|Li battery maintains a capacity retention of 86.2% after 50 cycles at a rate of 0.3 C. The influence of BaTiO_(3) ceramic powder on the properties of PAN-based polymer electrolytes is analyzed. Our results provide a new avenue for future research in the all-solid-state lithium battery technology.展开更多
基金Project supported by the Major Program of the National Natural Science Foundation of China (Grant No.22393904)the National Key Research and Development Program of China (Grant No.2022YFB2502200)+1 种基金Beijing Municipal Science&Technology Commission (Grant No.Z221100006722015)the New Energy Vehicle Power Battery Life Cycle Testing and Verification Public Service Platform Project (Grant No.2022-235-224)。
文摘Silicon(Si)is a competitive anode material owing to its high theoretical capacity and low electrochemical potential.Recently,the prospect of Si anodes in solid-state batteries(SSBs)has been proposed due to less solid electrolyte interphase(SEI)formation and particle pulverization.However,major challenges arise for Si anodes in SSBs at elevated temperatures.In this work,the failure mechanisms of Si-Li_(6)PS_(5)Cl(LPSC)composite anodes above 80℃are thoroughly investigated from the perspectives of interface stability and(electro)chemo-mechanical effect.The chemistry and growth kinetics of Lix Si|LPSC interphase are demonstrated by combining electrochemical,chemical and computational characterizations.Si and/or Si–P compound formed at Lix Si|LPSC interface prove to be detrimental to interface stability at high temperatures.On the other hand,excessive volume expansion and local stress caused by Si lithiation at high temperatures damage the mechanical structure of Si-LPSC composite anodes.This work elucidates the behavior and failure mechanisms of Si-based anodes in SSBs at high temperatures and provides insights into upgrading Si-based anodes for application in SSBs.
文摘Compared to commercial lithium-ion batteries, all-solid-state batteries can greatly increase the energy density, safety, and cycle life of batteries. The development of solid-state electrolyte with high lithium-ion conductivity and wide electrochemical window is the key for all-solid-state batteries. In this work, we report on the achievement of high ionic conductivity in the PAN/LiClO_(4)/BaTiO_(3) composite solid electrolyte (CSE) prepared by solution casting method. Our experimental results show that the PAN-based composite polymer electrolyte with 5 wt% BaTiO_(3) possesses a high room-temperature lithium-ion conductivity (9.85 × 10^(−4) S⋅cm^(−1)), high lithium-ion transfer number (0.63), wide electrochemical window (4.9 V vs Li+/Li). The Li|Li symmetric battery assembled with 5 wt% BaTiO_(3) can be stably circulated for 800 h at 0.1 mA⋅cm^(−2), and the LiFePO_(4)|CSE|Li battery maintains a capacity retention of 86.2% after 50 cycles at a rate of 0.3 C. The influence of BaTiO_(3) ceramic powder on the properties of PAN-based polymer electrolytes is analyzed. Our results provide a new avenue for future research in the all-solid-state lithium battery technology.
