A facile and efficient ball-milling assisted sol-gel synthesis route was developed to prepare triclinic e-LiVOPO_(4)(LVOP)material with lanthanum(La)and cerium(Ce)modification individually as well as simultaneously.An...A facile and efficient ball-milling assisted sol-gel synthesis route was developed to prepare triclinic e-LiVOPO_(4)(LVOP)material with lanthanum(La)and cerium(Ce)modification individually as well as simultaneously.An LVOP/LaPO_(4)/CePO_(4)composite cathode material was successfully synthesized and results show that La and Ce co-modification noticeably improves the electrochemical performance by enhancing the high voltage capacity upon cycling,which indicates contributions from the good ionic conductors LaPO_(4)and CePO_(4).The simultaneous La and Ce modification improves the high voltage performance significantly with an increase of 50%in high voltage capacity after 20 cycles compared to pure LVOP.It also shows stabilized cycling perfo rmance with 91%capacity rete ntion after 50 cycles at 0.1 C rate,along with high-rate capability with a capacity of 83.1 mAh/g compared to the pristine sample showing the capacity of 51.6 mAh/g at a high rate of 5C.This can be attributed to the good conductivity of LaPO_(4)and CePO_(4).In addition,the LVOP/LaPO_(4)/CePO_(4)composite and the pristine LVOP give a charge transfer resistance of-105 and-212Ω,respectively,showing much lower impedance due to a combination of La and Ce addition.展开更多
Lithium batteries(LIBs) with low capacity graphite anode(~372 mAh g-1) cannot meet the ever-growing demand for new energy electric vehicles and renewable energy storage.It is essential to replace graphite anode with h...Lithium batteries(LIBs) with low capacity graphite anode(~372 mAh g-1) cannot meet the ever-growing demand for new energy electric vehicles and renewable energy storage.It is essential to replace graphite anode with higher capacity anode materials for high-energy density LIBs.Silicon(Si) is well known to be a possible alternative for graphite anode due to its highest capacity(~4200 mAh g-1).Unfortunately,large volume change during lithiation and delithiation has prevented the Si anode from being commercialized.Metal silicides are a promising type of anode materials which can improve cycling stability via the accommodation of volume change by dispersing Si in the metal inactive/active matrix,while maintain greater capacity than graphite.Here,we present a classification of Si alloying with metals in periodic table of elements,review the available literature on metal silicide anodes to outline the progress in improving and understanding the electrochemical performance of various metal silicides,analyze the challenges that remain in using metal silicides,and offer perspectives regarding their future research and development as anode materials for commercial LIBs application.展开更多
基金the Anhui Natural Science Foundation(1908085ME151,KJ2020A0263)China Po stdoctoral Science Foundation(2020M673404)+2 种基金Anhui Province High-end Talent Grant(DT18100044)the National Level Foreign Expert Introduction Plan(G20190219004)the National Natural Science Foundation of China(52207246)。
文摘A facile and efficient ball-milling assisted sol-gel synthesis route was developed to prepare triclinic e-LiVOPO_(4)(LVOP)material with lanthanum(La)and cerium(Ce)modification individually as well as simultaneously.An LVOP/LaPO_(4)/CePO_(4)composite cathode material was successfully synthesized and results show that La and Ce co-modification noticeably improves the electrochemical performance by enhancing the high voltage capacity upon cycling,which indicates contributions from the good ionic conductors LaPO_(4)and CePO_(4).The simultaneous La and Ce modification improves the high voltage performance significantly with an increase of 50%in high voltage capacity after 20 cycles compared to pure LVOP.It also shows stabilized cycling perfo rmance with 91%capacity rete ntion after 50 cycles at 0.1 C rate,along with high-rate capability with a capacity of 83.1 mAh/g compared to the pristine sample showing the capacity of 51.6 mAh/g at a high rate of 5C.This can be attributed to the good conductivity of LaPO_(4)and CePO_(4).In addition,the LVOP/LaPO_(4)/CePO_(4)composite and the pristine LVOP give a charge transfer resistance of-105 and-212Ω,respectively,showing much lower impedance due to a combination of La and Ce addition.
基金financially supported by the School-Enterprise cooperation Project(RD18200058)the Anhui Natural Science Foundation(No.1908085ME151)+2 种基金the Anhui province high-end talent Grant(DT18100044)the Key Laboratory of Marine Materials and Related Technologies,CAS(2019K07)the National Foreign Expert Introduction Plan Project(G20190219004)。
文摘Lithium batteries(LIBs) with low capacity graphite anode(~372 mAh g-1) cannot meet the ever-growing demand for new energy electric vehicles and renewable energy storage.It is essential to replace graphite anode with higher capacity anode materials for high-energy density LIBs.Silicon(Si) is well known to be a possible alternative for graphite anode due to its highest capacity(~4200 mAh g-1).Unfortunately,large volume change during lithiation and delithiation has prevented the Si anode from being commercialized.Metal silicides are a promising type of anode materials which can improve cycling stability via the accommodation of volume change by dispersing Si in the metal inactive/active matrix,while maintain greater capacity than graphite.Here,we present a classification of Si alloying with metals in periodic table of elements,review the available literature on metal silicide anodes to outline the progress in improving and understanding the electrochemical performance of various metal silicides,analyze the challenges that remain in using metal silicides,and offer perspectives regarding their future research and development as anode materials for commercial LIBs application.
