Internal short circuits because of deformation or melting down of separators have been recognized as a root cause for many thermal runaway(TR)events of high-energy-density(HED)lithium-ion batteries(LIBs).Ceramic coati...Internal short circuits because of deformation or melting down of separators have been recognized as a root cause for many thermal runaway(TR)events of high-energy-density(HED)lithium-ion batteries(LIBs).Ceramic coating of the polyolefin separators is a promising strategy but generally hinders ionic conduction.In this study,we demonstrate that co-coating the separators with boehmite ceramics and Li_(1.5)Al_(0.5)Ti_(1.5)(PO_(4))_(3)(LATP)solid-state electrolytes could markedly improve the safety of LIBs while mitigating detrimental effects on electrochemical performance.We assembled HED(~350 Wh/kg)lithium-ion pouch cells with nickel-rich Li(Ni_(0.9)Co_(x)Mn_(0.1-x))O_(2) cathodes,silicon-based/graphite blended anodes,and co-coated separators of varying thicknesses.It is found that LATP reacts with the organic liquid electrolytes and lithium to generate a robust solid-electrolyte-interface-filled LATP layer during the formation,which can prevent the thermal deformation of separators.During the thermal abusive tests,the battery's TR failure thresholds raised from 146.2 to 162.0℃.Correspondingly,the direct failure cause of the cell TR hurdled the separator malfunction to the thermochemical reactions of the nickel-rich cathodes.Additionally,pouch cells exhibited impressive electrochemical performance,maintaining a capacity retention of 87.99%after 500 cycles at 1C.展开更多
基金supported by the National Natural Science Foundation of China(No.U21A2080)National Key Research and Development Program of China(No.2022YFE0202400)+3 种基金Beijing Natural Science Foundation(No.JQ22028)Jilin Province Science and Technology Major Project(No.20210301021GX)Youth Talent Support Program(No.SQ2022QB02427)Youth Foundation of China GRINM Group Corporation Limited(No.2023HX012).
文摘Internal short circuits because of deformation or melting down of separators have been recognized as a root cause for many thermal runaway(TR)events of high-energy-density(HED)lithium-ion batteries(LIBs).Ceramic coating of the polyolefin separators is a promising strategy but generally hinders ionic conduction.In this study,we demonstrate that co-coating the separators with boehmite ceramics and Li_(1.5)Al_(0.5)Ti_(1.5)(PO_(4))_(3)(LATP)solid-state electrolytes could markedly improve the safety of LIBs while mitigating detrimental effects on electrochemical performance.We assembled HED(~350 Wh/kg)lithium-ion pouch cells with nickel-rich Li(Ni_(0.9)Co_(x)Mn_(0.1-x))O_(2) cathodes,silicon-based/graphite blended anodes,and co-coated separators of varying thicknesses.It is found that LATP reacts with the organic liquid electrolytes and lithium to generate a robust solid-electrolyte-interface-filled LATP layer during the formation,which can prevent the thermal deformation of separators.During the thermal abusive tests,the battery's TR failure thresholds raised from 146.2 to 162.0℃.Correspondingly,the direct failure cause of the cell TR hurdled the separator malfunction to the thermochemical reactions of the nickel-rich cathodes.Additionally,pouch cells exhibited impressive electrochemical performance,maintaining a capacity retention of 87.99%after 500 cycles at 1C.
