为抑制高能锂离子电池负极材料Bi2Mn4O10容量的快速衰减,通过简单球磨法制备新型高纯Bi2Mn4O10/ECP-N(ECP-N为氮掺杂科琴黑)负极复合材料。所合成的Bi2Mn4O10/ECP-N复合材料在0.2C倍率下循环100次后可保持576.2m A·h/g的比容量,容...为抑制高能锂离子电池负极材料Bi2Mn4O10容量的快速衰减,通过简单球磨法制备新型高纯Bi2Mn4O10/ECP-N(ECP-N为氮掺杂科琴黑)负极复合材料。所合成的Bi2Mn4O10/ECP-N复合材料在0.2C倍率下循环100次后可保持576.2m A·h/g的比容量,容量保持率为75%,而纯Bi2Mn4O10的容量保持率仅为27%。3C倍率下Bi2Mn4O10/ECP-N复合材料的放电容量仍保持在236.1 m A·h/g。引入氮掺杂的科琴黑ECP-N不仅可以有效地提高比表面积以缓冲体积膨胀,增强材料的电导率和可湿性,而且还可以促进离子传输和可逆转化反应。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。
文摘为抑制高能锂离子电池负极材料Bi2Mn4O10容量的快速衰减,通过简单球磨法制备新型高纯Bi2Mn4O10/ECP-N(ECP-N为氮掺杂科琴黑)负极复合材料。所合成的Bi2Mn4O10/ECP-N复合材料在0.2C倍率下循环100次后可保持576.2m A·h/g的比容量,容量保持率为75%,而纯Bi2Mn4O10的容量保持率仅为27%。3C倍率下Bi2Mn4O10/ECP-N复合材料的放电容量仍保持在236.1 m A·h/g。引入氮掺杂的科琴黑ECP-N不仅可以有效地提高比表面积以缓冲体积膨胀,增强材料的电导率和可湿性,而且还可以促进离子传输和可逆转化反应。
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.
