As a unique microprobe for structure and dynamics of materials,neutron possesses superior ability in penetration as well as sensitivity for light and magnetic elements in comparison with X-ray and electron.As for the ...As a unique microprobe for structure and dynamics of materials,neutron possesses superior ability in penetration as well as sensitivity for light and magnetic elements in comparison with X-ray and electron.As for the research and development of lithium-ion batteries(LIBs),neutron diffraction techniques play an indispensable role in exploring the structural properties of various electrode materials,especially the detailed structural evolution of cathode and anode materials during electrochemical cycling.Moreover,based on thorough analysis of neutron diffraction results,an in-depth and systematic understanding of some fundamental mechanisms,such as the formation mechanism of defects and migration mechanism of lithium ions,could also be established,which is essential for the development of high-performance electrode materials for the next-generation LIBs.Nevertheless,that technique would not seem to be widely applied yet in comparison with the application of X-ray diffraction and more attention should be paid.To demonstrate the advantages of neutron diffraction technique in research of LIBs materials,this work systematically summarizes representative neutron diffraction studies on exploring structural details hidden in electrode materials and on probing structural evolution of electrode materials during charge/discharge processes.Prospects for further applications of neutron diffraction techniques in research of LIBs are also put forward.展开更多
Ytterbium purification by an electrolysis reduction in sulfuric acid medium was investigated without nitrogen or argon protection, in which Ru-Ir-Ti alloy nets and mercury were used as anode and cathode, respectively....Ytterbium purification by an electrolysis reduction in sulfuric acid medium was investigated without nitrogen or argon protection, in which Ru-Ir-Ti alloy nets and mercury were used as anode and cathode, respectively. How the conditions such as the acidities of cathode and anode solutions, and the concentration of Yb（ Ⅲ ） to affect the circuit and ratio of Yb（ Ⅱ ）/Yb （ Ⅲ ） in electrolysis reduction were studied.展开更多
High voltage is necessary for high energy lithium-ion batteries but difficult to achieve because of the highly deteriorated cyclability of the batteries.A novel strategy is developed to extend cyclability of a high vo...High voltage is necessary for high energy lithium-ion batteries but difficult to achieve because of the highly deteriorated cyclability of the batteries.A novel strategy is developed to extend cyclability of a high voltage lithium-ion battery,LiNi_(0.5)Mn_(1.5)O_(4)/Graphite(LNMO/Graphite)cell,which emphasizes a rational design of an electrolyte additive that can effectively construct protective interphases on anode and cathode and highly eliminate the effect of hydrogen fluoride(HF).5-Trifluoromethylpyridine-trime thyl lithium borate(LTFMP-TMB),is synthesized,featuring with multi-functionalities.Its anion TFMPTMB-tends to be enriched on cathode and can be preferentially oxidized yielding TMB and radical TFMP-.Both TMB and radical TFMP can combine HF and thus eliminate the detrimental effect of HF on cathode,while the TMB dragged on cathode thus takes a preferential oxidation and constructs a protective cathode interphase.On the other hand,LTFMP-TMB is preferentially reduced on anode and constructs a protective anode interphase.Consequently,a small amount of LTFMP-TMB(0.2%)in 1.0 M LiPF6in EC/DEC/EMC(3/2/5,wt%)results in a highly improved cyclability of LNMO/Graphite cell,with the capacity retention enhanced from 52%to 80%after 150 cycles at 0.5 C between 3.5 and 4.8 V.The as-developed strategy provides a model of designing electrolyte additives for improving cyclability of high voltage batteries.展开更多
基金supported by National Key R&D Program of China(2020YFA0406203)National Natural Science Foundation of China(Nos.52072008 and U2032167)+1 种基金Shenzhen Fundamental Research Program(No.GXWD 20201231165807007-20200807125314001)Guangdong Basic and Applied Basic Research Foundation(No.2022B1515120070).
文摘As a unique microprobe for structure and dynamics of materials,neutron possesses superior ability in penetration as well as sensitivity for light and magnetic elements in comparison with X-ray and electron.As for the research and development of lithium-ion batteries(LIBs),neutron diffraction techniques play an indispensable role in exploring the structural properties of various electrode materials,especially the detailed structural evolution of cathode and anode materials during electrochemical cycling.Moreover,based on thorough analysis of neutron diffraction results,an in-depth and systematic understanding of some fundamental mechanisms,such as the formation mechanism of defects and migration mechanism of lithium ions,could also be established,which is essential for the development of high-performance electrode materials for the next-generation LIBs.Nevertheless,that technique would not seem to be widely applied yet in comparison with the application of X-ray diffraction and more attention should be paid.To demonstrate the advantages of neutron diffraction technique in research of LIBs materials,this work systematically summarizes representative neutron diffraction studies on exploring structural details hidden in electrode materials and on probing structural evolution of electrode materials during charge/discharge processes.Prospects for further applications of neutron diffraction techniques in research of LIBs are also put forward.
文摘Ytterbium purification by an electrolysis reduction in sulfuric acid medium was investigated without nitrogen or argon protection, in which Ru-Ir-Ti alloy nets and mercury were used as anode and cathode, respectively. How the conditions such as the acidities of cathode and anode solutions, and the concentration of Yb（ Ⅲ ） to affect the circuit and ratio of Yb（ Ⅱ ）/Yb （ Ⅲ ） in electrolysis reduction were studied.
基金supported by the National Natural Science Foundation of China(22179041)。
文摘High voltage is necessary for high energy lithium-ion batteries but difficult to achieve because of the highly deteriorated cyclability of the batteries.A novel strategy is developed to extend cyclability of a high voltage lithium-ion battery,LiNi_(0.5)Mn_(1.5)O_(4)/Graphite(LNMO/Graphite)cell,which emphasizes a rational design of an electrolyte additive that can effectively construct protective interphases on anode and cathode and highly eliminate the effect of hydrogen fluoride(HF).5-Trifluoromethylpyridine-trime thyl lithium borate(LTFMP-TMB),is synthesized,featuring with multi-functionalities.Its anion TFMPTMB-tends to be enriched on cathode and can be preferentially oxidized yielding TMB and radical TFMP-.Both TMB and radical TFMP can combine HF and thus eliminate the detrimental effect of HF on cathode,while the TMB dragged on cathode thus takes a preferential oxidation and constructs a protective cathode interphase.On the other hand,LTFMP-TMB is preferentially reduced on anode and constructs a protective anode interphase.Consequently,a small amount of LTFMP-TMB(0.2%)in 1.0 M LiPF6in EC/DEC/EMC(3/2/5,wt%)results in a highly improved cyclability of LNMO/Graphite cell,with the capacity retention enhanced from 52%to 80%after 150 cycles at 0.5 C between 3.5 and 4.8 V.The as-developed strategy provides a model of designing electrolyte additives for improving cyclability of high voltage batteries.
