The high safety of aqueous magnesium ion batteries(AMIBs)contrasts with their limited electrochemical performance.To overcome electrolyte-induced parasitic reactions,it is essential to understand the dynamic evolution...The high safety of aqueous magnesium ion batteries(AMIBs)contrasts with their limited electrochemical performance.To overcome electrolyte-induced parasitic reactions,it is essential to understand the dynamic evolution of concentration-dependent metal ion solvation structures(MISSs).This study systematically reveals the solvation structure evolution of MgCl_(2) aqueous solutions across a full concentration range(0-30 M)and its impact on electrochemical properties using molecular dynamics simulations and density functional theory calculations.Results indicate that six characteristic solvation configurations exist,exhibiting a dynamic,concentration-dependent inter-evolution defined as the solvation structure evolutionary processes(SSEP).The four-phase glass transition mechanism in solvation structure evolution is revealed by analyzing the percentage of each type of solvation structure in different concentrations.The study shows that conductivity is directly related to the dynamic transitions of dominant solvation structures,with a shift in the Mg^(2+) coordination mode—from octahedral through pentahedral intermediates to tetrahedral—revealing a concentration-dependent ion transport mechanism.At low concentrations,free-state stochastic diffusion predominates,reaching a maximum conductivity before transitioning to relay transport within a restricted network at high concentrations.Key contributions include:a general strategy for electrolyte design based on the solvation structure evolution process,which quantitatively correlates structural occupancy with migration properties,and the“Concentration Window”regulation model that balances high conductivity with reduced side reactions.These findings clarify the structural origins of anomalous conductivity in highly concentrated electrolytes and establish a mapping between microstructural evolution and macroscopic performance,providing a theoretical basis for engineering high-security electrolytes of AMIBs.展开更多
Recently,aqueous rechargeable batteries have played an essential role in developing renewable energy due to the merits of low cost,high security,and high energy density.Among various aqueous-based batteries,aqueous ma...Recently,aqueous rechargeable batteries have played an essential role in developing renewable energy due to the merits of low cost,high security,and high energy density.Among various aqueous-based batteries,aqueous magnesium ion batteries(AMIBs)have rich reserves and high theoretical specific capacity(3833 mAh cm3).However,for future industrialization,AMIBs still face many scientific issues to be solved,such as the slow diffusion of magnesium ions in the material structure,the desolvation penalty at electrode-electrolyte interfaces,the cost of water-in-salt electrolyte,the low voltage of traditional aqueous electrolyte,etc.And yet a comprehensive summary of the components of AMIBs is lacking in the research community.This review mainly introduces the exploration and development of AMIB systems and related components.We conduct an in-depth study of the cathode materials appropriate for magnesium ion batteries from their crystal structures,focusing primarily on layered structures,spinel structures,tunnel structures,and three-dimensional framework structures.We also investigate the anode materials,ranging from inorganic materials to organic materials,as well as the electrolyte materials(from the traditional electrolyte to water-in-salt electrolyte).Finally,some perspectives on ensuing optimization design for future research efforts in the AMIBs field are summarized.展开更多
基金supported by the National Natural Science Foundation of China(No.11047164)the National Key Laboratory of Infrared Detection Technologies(No.IRDT-23-S01)the Shanghai Explorer Program(No.24TS1403400)。
文摘The high safety of aqueous magnesium ion batteries(AMIBs)contrasts with their limited electrochemical performance.To overcome electrolyte-induced parasitic reactions,it is essential to understand the dynamic evolution of concentration-dependent metal ion solvation structures(MISSs).This study systematically reveals the solvation structure evolution of MgCl_(2) aqueous solutions across a full concentration range(0-30 M)and its impact on electrochemical properties using molecular dynamics simulations and density functional theory calculations.Results indicate that six characteristic solvation configurations exist,exhibiting a dynamic,concentration-dependent inter-evolution defined as the solvation structure evolutionary processes(SSEP).The four-phase glass transition mechanism in solvation structure evolution is revealed by analyzing the percentage of each type of solvation structure in different concentrations.The study shows that conductivity is directly related to the dynamic transitions of dominant solvation structures,with a shift in the Mg^(2+) coordination mode—from octahedral through pentahedral intermediates to tetrahedral—revealing a concentration-dependent ion transport mechanism.At low concentrations,free-state stochastic diffusion predominates,reaching a maximum conductivity before transitioning to relay transport within a restricted network at high concentrations.Key contributions include:a general strategy for electrolyte design based on the solvation structure evolution process,which quantitatively correlates structural occupancy with migration properties,and the“Concentration Window”regulation model that balances high conductivity with reduced side reactions.These findings clarify the structural origins of anomalous conductivity in highly concentrated electrolytes and establish a mapping between microstructural evolution and macroscopic performance,providing a theoretical basis for engineering high-security electrolytes of AMIBs.
基金supported by the National Natural Science Foundation of China(No.52071171,52202248)Liaoning Revitalization Talents Program-Pan Deng Scholars(XLYC1802005)+7 种基金Liaoning BaiQianWan Talents Program(LNBQW2018B0048)Natural Science Fund of Liaoning Province for Excellent Young Scholars(2019-YQ-04)Key Project of Scientific Research of the Education Department of Liaoning Province(LZD201902)Shenyang Science and Technology Project(21-108-9-04)the Research Fund for the Doctoral Program of Liaoning Province(2022-BS-114)Australian Research Council(ARC)through Future Fellowship(FT210100298)Discovery Project(DP220100603)Linkage Project(LP210200504)schemes,CSIRO Energy Centre and Kick-Start Project.
文摘Recently,aqueous rechargeable batteries have played an essential role in developing renewable energy due to the merits of low cost,high security,and high energy density.Among various aqueous-based batteries,aqueous magnesium ion batteries(AMIBs)have rich reserves and high theoretical specific capacity(3833 mAh cm3).However,for future industrialization,AMIBs still face many scientific issues to be solved,such as the slow diffusion of magnesium ions in the material structure,the desolvation penalty at electrode-electrolyte interfaces,the cost of water-in-salt electrolyte,the low voltage of traditional aqueous electrolyte,etc.And yet a comprehensive summary of the components of AMIBs is lacking in the research community.This review mainly introduces the exploration and development of AMIB systems and related components.We conduct an in-depth study of the cathode materials appropriate for magnesium ion batteries from their crystal structures,focusing primarily on layered structures,spinel structures,tunnel structures,and three-dimensional framework structures.We also investigate the anode materials,ranging from inorganic materials to organic materials,as well as the electrolyte materials(from the traditional electrolyte to water-in-salt electrolyte).Finally,some perspectives on ensuing optimization design for future research efforts in the AMIBs field are summarized.
