Although showing huge potential in prospering the marketplace of all-solid-state lithium metal batteries(ASSLMBs),garnet-type solid electrolytes(Li6.5La3Zr1.5Ta0.6O12,LLZTO)are critically plagued by interface instabil...Although showing huge potential in prospering the marketplace of all-solid-state lithium metal batteries(ASSLMBs),garnet-type solid electrolytes(Li6.5La3Zr1.5Ta0.6O12,LLZTO)are critically plagued by interface instability with Li anode and the vulnerability to Li dendrite,which are attributed to poor Li diffusion kinetic in bulk Li metal.Herein,a LixAg solid solution alloy with high Li diffusion kinetic is reported as a mixed ionelectron conductor(MIEC)alloy anode.The high Li diffusion kinetic stemming from a low eutectic point and a high mutual solubility of LixAg could reduce the Li concentration gradient in the anode,regulate Li electrochemical potential,and change the relative local overpotential for Li stripping/plating in the anode.Notably,Li stripping/plating prefers energetically at the LixAg/current collector interface rather than the LLZTO/LixAg interface.Therefore,the contact loss is avoided at the LLZTO/LixAg interface.As a result,excellent cycling stability(~1,200 h at 0.2 mA/cm2),and dendrites tolerance(critical current density of 1.2 mA/cm2)are demonstrated by using LixAg as anode.Further research has elucidated that those alloys with low eutectic temperature and high mutual solubility with lithium should be focused on,as they would provide and maintain a soft lattice and a high lithium diffusion rate during composition change.This provides a basis for the selection of alloy phases in negative electrode materials,as well as their application in garnet-based ASSLMBs.展开更多
All-solid-state batteries(ASSBs)using sulfide electrolytes hold promise for next-generation battery technology.Although using a pure Li metal anode is believed to maximize battery energy density,numerous recent studie...All-solid-state batteries(ASSBs)using sulfide electrolytes hold promise for next-generation battery technology.Although using a pure Li metal anode is believed to maximize battery energy density,numerous recent studies have implicated that Li-ion anodes(e.g.,graphite and Si)are more realistic candidates due to their interfacial compatibility with sulfide electrolytes.However,those Li-ion ASSBs suffer from an issue similar to liquid Li-ion batteries,which is a loss of active Li inventory owing to interfacial side reactions between electrode components,resulting in reduced available capacities and shortened cycle life.Herein,for the first time,we explore the potential of Li_(3)P for cathode prelithiation of Li-ion ASSBs.We identify that the crystallized Li_(3)P(c-Li_(3)P)has room-temperature ionic and electronic conductivities of both over 1o-4 s/cm.Such a mixed ion-electron conduct-ing feature ensures that the neat c-LisP affords a high Li+-releasing capacity of 983 mAh/g in ASSBs during the first charging.Moreover,the electro-chemical delithiation of c-LisP takes place below 2 V versus Li+/Li,while its lithiation dominates below 1 V versus Lit/Li.Once used as a cathode prelithiation regent for ASSBs,c-Li_(3)P only functions as a Li+donor without lithiation activity and can adequately compensate for the Li loss with minimal dosage added.Besides mitigating first-cycle Li loss,c-LisP prelithiation can also improve the battery cyclability by sustained release of low-dosage Li+ions in subsequent cycles,which have been embodied in several full ASSBs by coupling a LiCoO2 cathode with various types of anodes(including graphite,in foil,Sb,and Si anode).Our work provides a universal cathode prelithiation strategy for high-efficiency Li-ion AsSBs.展开更多
基金supported by the Natural Science Foundation of China(Grant 51977097,52207234)the Science and Technology Project of State Grid Corporation of China(Grant No.5419-202199552A-0-5-ZN).
文摘Although showing huge potential in prospering the marketplace of all-solid-state lithium metal batteries(ASSLMBs),garnet-type solid electrolytes(Li6.5La3Zr1.5Ta0.6O12,LLZTO)are critically plagued by interface instability with Li anode and the vulnerability to Li dendrite,which are attributed to poor Li diffusion kinetic in bulk Li metal.Herein,a LixAg solid solution alloy with high Li diffusion kinetic is reported as a mixed ionelectron conductor(MIEC)alloy anode.The high Li diffusion kinetic stemming from a low eutectic point and a high mutual solubility of LixAg could reduce the Li concentration gradient in the anode,regulate Li electrochemical potential,and change the relative local overpotential for Li stripping/plating in the anode.Notably,Li stripping/plating prefers energetically at the LixAg/current collector interface rather than the LLZTO/LixAg interface.Therefore,the contact loss is avoided at the LLZTO/LixAg interface.As a result,excellent cycling stability(~1,200 h at 0.2 mA/cm2),and dendrites tolerance(critical current density of 1.2 mA/cm2)are demonstrated by using LixAg as anode.Further research has elucidated that those alloys with low eutectic temperature and high mutual solubility with lithium should be focused on,as they would provide and maintain a soft lattice and a high lithium diffusion rate during composition change.This provides a basis for the selection of alloy phases in negative electrode materials,as well as their application in garnet-based ASSLMBs.
基金support from the National Natural Science Foundation of China(Nos.51972257,52172229,and 21401145)the Guangdong_Key Areas Research and Development Program(Nos.2020B090904001and2019B090909003)the Fundamental Research Funds for the Central Universities(No.2022IVA197).
文摘All-solid-state batteries(ASSBs)using sulfide electrolytes hold promise for next-generation battery technology.Although using a pure Li metal anode is believed to maximize battery energy density,numerous recent studies have implicated that Li-ion anodes(e.g.,graphite and Si)are more realistic candidates due to their interfacial compatibility with sulfide electrolytes.However,those Li-ion ASSBs suffer from an issue similar to liquid Li-ion batteries,which is a loss of active Li inventory owing to interfacial side reactions between electrode components,resulting in reduced available capacities and shortened cycle life.Herein,for the first time,we explore the potential of Li_(3)P for cathode prelithiation of Li-ion ASSBs.We identify that the crystallized Li_(3)P(c-Li_(3)P)has room-temperature ionic and electronic conductivities of both over 1o-4 s/cm.Such a mixed ion-electron conduct-ing feature ensures that the neat c-LisP affords a high Li+-releasing capacity of 983 mAh/g in ASSBs during the first charging.Moreover,the electro-chemical delithiation of c-LisP takes place below 2 V versus Li+/Li,while its lithiation dominates below 1 V versus Lit/Li.Once used as a cathode prelithiation regent for ASSBs,c-Li_(3)P only functions as a Li+donor without lithiation activity and can adequately compensate for the Li loss with minimal dosage added.Besides mitigating first-cycle Li loss,c-LisP prelithiation can also improve the battery cyclability by sustained release of low-dosage Li+ions in subsequent cycles,which have been embodied in several full ASSBs by coupling a LiCoO2 cathode with various types of anodes(including graphite,in foil,Sb,and Si anode).Our work provides a universal cathode prelithiation strategy for high-efficiency Li-ion AsSBs.
