材料期刊网

采用模板-电沉积法制备锂离子电池Sn-Co-C微孔负极。首先,采用聚合法制备PS球乳液。然后,再以柠檬酸、EDTA为络合剂,CoCl2、SnCl4为主盐,添加甲酸和PS球乳液的电解液中,电沉积制备Sn-Co-C微孔复合电极材料。随后采用EDS、XRD和SEM分析其元素成分、晶体结构和表面形貌。最后采用恒流充放电和交流阻抗测试其电化学性能。结果表明,电极表面的微孔可以缓解锂电池充放电过程中产生的体积变化所导致的活性物质脱落,提高循环性能和寿命。Sn-Co-C负极组成的电池首次充放电比容量分别为705.4和1105 mA.h.g-1,循环126次后充放电比容量分别为393.3和403.2 mA.h.g-1。

Sn-Co-C cathode with micro-pore structure used for lithium-ion battery was synthesized by template-assisted electrodeposition.Firstly,PS emulsion were synthesized by polymerization.Secondly,Sn-Co-C alloy negative electrodes were prepared by electrodeposition in a solution containing citric acid and EDTA（as the complexing agents）,CoCl2 and SnCl4（as the major salts）,formic acid and PS emulsion,and then EDS,XRD and SEM were used to analyse the element constituent,crystal structure and surface morphology of the deposits respectively.Finally,constant current charge and discharge system and EIS were employed to study their electrochemical performance.The experimental results show that the micropores structure on the surface of Sn-Co-C alloy electrode can improve the spalling behavior of active materials caused by volume changes during the charge and discharge procedures and enhance the cycle performance and life of the lithium-ion battery effectively.The first charge and discharge specific capacity is 705.4 mA·h·g-1 and 1105 mA·h·g-1,respectively.After cycling for 126 times,the charge and discharge specific capacity still had the values of 393.3 mA·h·g-1and 403.2 mA·h·g-1.