To inhibit rapid capacity attenuation of Bi2Mn4O10 anode material in high-energy lithium-ion batteries,a novel high-purity anode composite material Bi2Mn4O10/ECP-N(ECP-N:N-doped Ketjen black)was prepared via an uncomp...To inhibit rapid capacity attenuation of Bi2Mn4O10 anode material in high-energy lithium-ion batteries,a novel high-purity anode composite material Bi2Mn4O10/ECP-N(ECP-N:N-doped Ketjen black)was prepared via an uncomplicated ball milling method.The as-synthesized Bi2Mn4O10/ECP-N composite demonstrated a great reversible specific capacity of 576.2 m A·h/g after 100 cycles at 0.2 C with a large capacity retention of 75%.However,the capacity retention of individual Bi2Mn4O10 was only 27%.Even at 3 C,a superior rate capacity of 236.1 m A·h/g was retained.Those remarkable electrochemical performances could give the credit to the introduction of ECP-N,which not only effectively improves the specific surface area to buffer volume expansion and enhances conductivity and wettability of composites but also accelerates the ion transfer and the reversible conversion reaction.展开更多
Li_(3)VO_4 has been considered as a promising insertion-type anode for lithium-ion batteries due to its high theoretical specific capacity and suitable operating voltage platform. However, this promising anode still s...Li_(3)VO_4 has been considered as a promising insertion-type anode for lithium-ion batteries due to its high theoretical specific capacity and suitable operating voltage platform. However, this promising anode still suffers from poor electrical conductivity. To address this issue, herein, a porous carbon supported Li_(3)VO_4 composites(Li_(3)VO_4/C) via a facile agitation-drying method combined with subsequent calcination is reported, in which Ketjen black carbon with high porosity, easy dispersion and excellent conductivity can serve as one of carbon sources. The Li_(3)VO_4/C composite prepared at 700 ℃ with a carbon content of~10% exhibits the optimized structure. The void space of the composite accommodates the volume changes during the charge/discharge process.Meanwhile, the carbon shell serves as a conductive skeleton to provide bi-continuous Li ions and electrons pathways. Electrochemical results reveal that the composite delivers a high initial discharge capacity of 572 m Ahág^(-1) and maintains a capacity of 442.9 m Ahág^(-1) after 100 cycles at 100 m Aág^(-1). Even at a high current density of 2 Aág^(-1), a considerable capacity of 243.8 m Ahág^(-1) can still be obtained. This work provides a promising approach for the practical application of Li_(3)VO_4 as anode material for LIBs.展开更多
基金Project(2019zzts502)supported by the Fundamental Research Funds for the Central Universities of Central South University,ChinaProject(2018GK4001)supported by the Scientific and Technological Breakthrough and Major Achievements Transformation of Strategic Emerging Industries of Hunan Province,China。
文摘To inhibit rapid capacity attenuation of Bi2Mn4O10 anode material in high-energy lithium-ion batteries,a novel high-purity anode composite material Bi2Mn4O10/ECP-N(ECP-N:N-doped Ketjen black)was prepared via an uncomplicated ball milling method.The as-synthesized Bi2Mn4O10/ECP-N composite demonstrated a great reversible specific capacity of 576.2 m A·h/g after 100 cycles at 0.2 C with a large capacity retention of 75%.However,the capacity retention of individual Bi2Mn4O10 was only 27%.Even at 3 C,a superior rate capacity of 236.1 m A·h/g was retained.Those remarkable electrochemical performances could give the credit to the introduction of ECP-N,which not only effectively improves the specific surface area to buffer volume expansion and enhances conductivity and wettability of composites but also accelerates the ion transfer and the reversible conversion reaction.
基金National Natural Science Foundation of China(51372113,51772148)Top-notch Academic Programs Project of Jiangsu Higher Education Institutions(TAPP,PPZY2015B128)Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
基金financially supported by the National Natural Science Foundation of China (Nos. 51874362 and51872334)the Natural Science Foundation of Hunan Province,China(No. 2018JJ1036)the National Key Research and Development Program of China (No. 2018YFB0104200)。
文摘Li_(3)VO_4 has been considered as a promising insertion-type anode for lithium-ion batteries due to its high theoretical specific capacity and suitable operating voltage platform. However, this promising anode still suffers from poor electrical conductivity. To address this issue, herein, a porous carbon supported Li_(3)VO_4 composites(Li_(3)VO_4/C) via a facile agitation-drying method combined with subsequent calcination is reported, in which Ketjen black carbon with high porosity, easy dispersion and excellent conductivity can serve as one of carbon sources. The Li_(3)VO_4/C composite prepared at 700 ℃ with a carbon content of~10% exhibits the optimized structure. The void space of the composite accommodates the volume changes during the charge/discharge process.Meanwhile, the carbon shell serves as a conductive skeleton to provide bi-continuous Li ions and electrons pathways. Electrochemical results reveal that the composite delivers a high initial discharge capacity of 572 m Ahág^(-1) and maintains a capacity of 442.9 m Ahág^(-1) after 100 cycles at 100 m Aág^(-1). Even at a high current density of 2 Aág^(-1), a considerable capacity of 243.8 m Ahág^(-1) can still be obtained. This work provides a promising approach for the practical application of Li_(3)VO_4 as anode material for LIBs.