Elevating the operating voltage is an effective approach to improve the reversible capacity of ultra-high nickel layered oxide cathode LiNi_(x)Co_(y)Mn_(z)O_(2)(NCM,x≥0.8)and solve the"range anxiety"confusi...Elevating the operating voltage is an effective approach to improve the reversible capacity of ultra-high nickel layered oxide cathode LiNi_(x)Co_(y)Mn_(z)O_(2)(NCM,x≥0.8)and solve the"range anxiety"confusion of electric vehicles.However,the undesirable surface reconstruction induced by the high cut-off voltage has a fatal impact on the thermodynamic stability of the material,inevitably leading to fast capacity degradation.Herein,a mechanical fusion aided by alcohol is suggested to create a stable olivine structure for the single-crystal(SC)ultrahigh-nickel cathode LiNi_(0.92)Co_(0.04)Mn_(0.04)O_(2).The addition of nanoparticles effectively bridges the void of SC-NCM,builds an ideal particle grading,and significantly raises the cost efficiency,as well as promotes the cycling stability and safety of the full cell.Remarkably,the layered/olivine mixture forms a perfect shield by lowering the surface area between the NCM cathode and electrolyte,hence mitigating side reactions and contributing to an incredibly thin and stable cathode/electrolyte interface.Furthermore,the thermodynamic stability of highly delithiated NCM is improved,as both the particle cracks and structural degradation are simultaneously postponed.Consequently,the maximum temperature of the single-crystal LiNi_(0.92)Co_(0.04)Mn_(0.04)O_(2)@LiFePO_(4)‖graphite pouch full cell is dramatically reduced from 599.4 to 351.4℃,and the full cell achieves 88.2%capacity retention after 800 cycles,demonstrating excellent thermal stability and cycling stability.This facile strategy provides a feasible technical reference for further exploiting the ultrahigh-capacity,highsafety,and long-life Ni-rich cathode for commercial application of lithium-ion batteries(LIBs).展开更多
Purpose:As smartphones become ubiquitous,it is important to understand emerging information behavior as a result of wide spread use of smartphones.The purpose of this study is to investigate information behavior in th...Purpose:As smartphones become ubiquitous,it is important to understand emerging information behavior as a result of wide spread use of smartphones.The purpose of this study is to investigate information behavior in the mobile environment by studying undergraduate smartphone users in China.Design/methodology/approach:This study is based on a survey of 205 undergraduate students in China.Findings:Smartphones are used predominantly for accessing news and connecting to social media,rather than for academic purposes such as accessing library resources or researching.While students use smartphones for reading e-books,much of this reading is recreational during their spare time.Research limitations:The inherent limitations of self-reported measures and the small sample size of this study mean that the results cannot be generalized across different age groups and cultures.Practical implications:When targeting users on the move,information professionals should be aware that the needs and behaviors of smartphone readers are significantly different compared to users of fixed devices,and should provide services in a mobile-friendly way.Originality/value:The younger generation is accustomed to instant information access.For libraries to relevant,they must redesign their services.It is important for libraries to leverage the strengths of mobile technology and to balance traditional services with mobile delivery.Even though many mobile users will use desktop or laptop computers to access library resources,they will benefit from the availability of mobile-friendly library services.展开更多
基金the support from the Natural Science Foundation of Hunan Province,China(2024JJ7301)the science and technology innovation Program of Hunan Province(2024JK2097)+5 种基金the Project of the Scientific Research Fund of Hunan Provincial Education Department(No.22C0383)Changde Scientific and Technological Innovation Plan(CDKJJ20220517)Start-up Foundation for Doctors of Hunan University of Arts and Science(No.22BSQD22,21BSQD14 and 21BSQD15)Aid Program for Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Provincepartially supported by the Research Grants Council of the Hong Kong Special Administrative Region,China(PolyU152178/20E)the Innovation and Technology Commission of Hong Kong(MHP/080/22)。
文摘Elevating the operating voltage is an effective approach to improve the reversible capacity of ultra-high nickel layered oxide cathode LiNi_(x)Co_(y)Mn_(z)O_(2)(NCM,x≥0.8)and solve the"range anxiety"confusion of electric vehicles.However,the undesirable surface reconstruction induced by the high cut-off voltage has a fatal impact on the thermodynamic stability of the material,inevitably leading to fast capacity degradation.Herein,a mechanical fusion aided by alcohol is suggested to create a stable olivine structure for the single-crystal(SC)ultrahigh-nickel cathode LiNi_(0.92)Co_(0.04)Mn_(0.04)O_(2).The addition of nanoparticles effectively bridges the void of SC-NCM,builds an ideal particle grading,and significantly raises the cost efficiency,as well as promotes the cycling stability and safety of the full cell.Remarkably,the layered/olivine mixture forms a perfect shield by lowering the surface area between the NCM cathode and electrolyte,hence mitigating side reactions and contributing to an incredibly thin and stable cathode/electrolyte interface.Furthermore,the thermodynamic stability of highly delithiated NCM is improved,as both the particle cracks and structural degradation are simultaneously postponed.Consequently,the maximum temperature of the single-crystal LiNi_(0.92)Co_(0.04)Mn_(0.04)O_(2)@LiFePO_(4)‖graphite pouch full cell is dramatically reduced from 599.4 to 351.4℃,and the full cell achieves 88.2%capacity retention after 800 cycles,demonstrating excellent thermal stability and cycling stability.This facile strategy provides a feasible technical reference for further exploiting the ultrahigh-capacity,highsafety,and long-life Ni-rich cathode for commercial application of lithium-ion batteries(LIBs).
文摘Purpose:As smartphones become ubiquitous,it is important to understand emerging information behavior as a result of wide spread use of smartphones.The purpose of this study is to investigate information behavior in the mobile environment by studying undergraduate smartphone users in China.Design/methodology/approach:This study is based on a survey of 205 undergraduate students in China.Findings:Smartphones are used predominantly for accessing news and connecting to social media,rather than for academic purposes such as accessing library resources or researching.While students use smartphones for reading e-books,much of this reading is recreational during their spare time.Research limitations:The inherent limitations of self-reported measures and the small sample size of this study mean that the results cannot be generalized across different age groups and cultures.Practical implications:When targeting users on the move,information professionals should be aware that the needs and behaviors of smartphone readers are significantly different compared to users of fixed devices,and should provide services in a mobile-friendly way.Originality/value:The younger generation is accustomed to instant information access.For libraries to relevant,they must redesign their services.It is important for libraries to leverage the strengths of mobile technology and to balance traditional services with mobile delivery.Even though many mobile users will use desktop or laptop computers to access library resources,they will benefit from the availability of mobile-friendly library services.
