Rare earth-Mg-Ni-based alloys with superlattice structures are new generation negative electrode materials for the nickel metal hydride batteries.Among them,the novel AB_(4)-type superlattice structure alloy is suppos...Rare earth-Mg-Ni-based alloys with superlattice structures are new generation negative electrode materials for the nickel metal hydride batteries.Among them,the novel AB_(4)-type superlattice structure alloy is supposed to have superior cycling stability and rate capability.Yet its preparation is hindered by the crucial requirement of temperature and the special composition which is close to the other superlattice structure.Here,we prepare rare earth-Mg-Ni-based alloy and study the phase transformation of alloys to make clear the formation of AB_(4)-type phase.It is found Pr_(5)Co_(19)-type phase is converted from Ce_(5)Co_(19)-type phase and shows good stability at higher temperature compared to the Ce_(5)Co_(19)-type phase in the range of 930-970℃.Afterwards,with further 5℃increasing,AB_(4)-type superlattice structure forms at a temperature of 975℃by consuming Pr_(5)Co_(19)-type phase.In contrast with A_(5)B_(19)-type alloy,AB_(4)-type alloy has superior rate capability owing to the dominant advantages of charge transfer and hydrogen diffusion.Besides,AB_(4)-type alloy shows long lifespan whose capacity retention rates are 89.2%at the 100;cycle and 82.8%at the 200;cycle,respectively.AB_(4)-type alloy delivers 1.53 wt.%hydrogen storage capacity at room temperature and exhibits higher plateau pressure than Pr_(5)Co_(19)-type alloy.The work provides novel AB_(4)-type alloy with preferable electrochemical performance as negative electrode material to inspire the development of nickel metal hydride batteries.展开更多
The improvement of hydrogen storage materials is a key issue for storage and delivery of hydrogen energy before its potential can be realized. As hydrogen storage media, rare-earth hydrogen storage materials have been...The improvement of hydrogen storage materials is a key issue for storage and delivery of hydrogen energy before its potential can be realized. As hydrogen storage media, rare-earth hydrogen storage materials have been systematically studied in order to improve storage capacity, kinetics, thermodynamics and electrochemical performance. In this review, we focus on recent research progress of gaseous sorption and electrochemical hydrogen storage properties of rare-earth alloys and highlight their commercial applications including hydrogen storage tanks and nickel metal hydride batteries. Furthermore, development trend and prospective of rare-earth hydrogen storage materials are discussed.展开更多
The properties of La0.45Ce0.2Nd0.2Pr0.15Ni3.55Co0.75 alloy electrode com-pared with those of La0.65Nd0.2Pr0.15Ni3.55Co0.75Mn0.4Al0.3 have been investigated, in addition,the effects of Ce have been disscussed. The La0....The properties of La0.45Ce0.2Nd0.2Pr0.15Ni3.55Co0.75 alloy electrode com-pared with those of La0.65Nd0.2Pr0.15Ni3.55Co0.75Mn0.4Al0.3 have been investigated, in addition,the effects of Ce have been disscussed. The La0.65Nd0.2Pr0.15Ni3.55Co0.75Mn0.4 alloy electrodeshows a high discharge capacity and rate capability but low cycling stability. With partial sub-stitution for La by Ce, i.e. the La0.45Ce0.2Nd0.2Pr0.15Ni3.55Co0.75 alloy electrode showsa good cycling stability, which decays only 12% of maximum capacity （310 mA.h.g-1） after 300cycles.展开更多
基金financially supported by the Natural Science Foundation of Hebei Province(Nos.E2019203414,E2020203081 and E2019203161)the National Natural Science Foundation of China(Nos.51701175 and 51971197)+1 种基金the Innovation Fund for the Graduate Students of Hebei Province(No.CXZZBS2020062)the Doctoral Fund of Yanshan University(No.BL19031)
文摘Rare earth-Mg-Ni-based alloys with superlattice structures are new generation negative electrode materials for the nickel metal hydride batteries.Among them,the novel AB_(4)-type superlattice structure alloy is supposed to have superior cycling stability and rate capability.Yet its preparation is hindered by the crucial requirement of temperature and the special composition which is close to the other superlattice structure.Here,we prepare rare earth-Mg-Ni-based alloy and study the phase transformation of alloys to make clear the formation of AB_(4)-type phase.It is found Pr_(5)Co_(19)-type phase is converted from Ce_(5)Co_(19)-type phase and shows good stability at higher temperature compared to the Ce_(5)Co_(19)-type phase in the range of 930-970℃.Afterwards,with further 5℃increasing,AB_(4)-type superlattice structure forms at a temperature of 975℃by consuming Pr_(5)Co_(19)-type phase.In contrast with A_(5)B_(19)-type alloy,AB_(4)-type alloy has superior rate capability owing to the dominant advantages of charge transfer and hydrogen diffusion.Besides,AB_(4)-type alloy shows long lifespan whose capacity retention rates are 89.2%at the 100;cycle and 82.8%at the 200;cycle,respectively.AB_(4)-type alloy delivers 1.53 wt.%hydrogen storage capacity at room temperature and exhibits higher plateau pressure than Pr_(5)Co_(19)-type alloy.The work provides novel AB_(4)-type alloy with preferable electrochemical performance as negative electrode material to inspire the development of nickel metal hydride batteries.
基金supported by the National Natural Science Foundation of China(Grant No.21521092)the Major Scientific and Technological Developing Project of Changchun City(Grant No.17SS013)+1 种基金the Scientific and Technological Developing Project of Jilin Province(Grant No.20180201098GX)the Natural Science Foundation of Jiangsu Province(Grant No.BK20141174)
文摘The improvement of hydrogen storage materials is a key issue for storage and delivery of hydrogen energy before its potential can be realized. As hydrogen storage media, rare-earth hydrogen storage materials have been systematically studied in order to improve storage capacity, kinetics, thermodynamics and electrochemical performance. In this review, we focus on recent research progress of gaseous sorption and electrochemical hydrogen storage properties of rare-earth alloys and highlight their commercial applications including hydrogen storage tanks and nickel metal hydride batteries. Furthermore, development trend and prospective of rare-earth hydrogen storage materials are discussed.
文摘The properties of La0.45Ce0.2Nd0.2Pr0.15Ni3.55Co0.75 alloy electrode com-pared with those of La0.65Nd0.2Pr0.15Ni3.55Co0.75Mn0.4Al0.3 have been investigated, in addition,the effects of Ce have been disscussed. The La0.65Nd0.2Pr0.15Ni3.55Co0.75Mn0.4 alloy electrodeshows a high discharge capacity and rate capability but low cycling stability. With partial sub-stitution for La by Ce, i.e. the La0.45Ce0.2Nd0.2Pr0.15Ni3.55Co0.75 alloy electrode showsa good cycling stability, which decays only 12% of maximum capacity （310 mA.h.g-1） after 300cycles.
