硅/石墨负极中硅的体电阻率和掺杂类型对锂离子电池电化学性能的影响  

Effects of Bulk Electrical Resistivity and Doping Type of Silicon on the Electrochemical Performance of Lithium-ion Batteries with Silicon/Graphite Anodes

作　　者：金晨鑫 徐国军 刘烈凯 岳之浩[1] 李晓敏[1] 汤昊[1] 周浪[1] 

机构地区：[1]南昌大学光伏研究院,南昌330031

出　　处：《材料导报》2017年第22期10-14,共5页Materials Reports

基　　金：中国博士后基金(2016M592115);江西省博士后基金(2015KY12);江西教育厅项目(150184);国家自然科学基金(61464007);江西省自然科学基金(2015BAB207055);南昌大学研究生创新专项资金项目(cx2016014)

摘　　要：将电阻率为1Ω·cm、0.1Ω·cm、0.01Ω·cm、0.001Ω·cm的n型掺杂硅片以及电阻率为1Ω·cm、0.001Ω·cm的p型掺杂硅片球磨制成6种硅粉,并分别将其与石墨按照5∶95的质量比进行混合,用作锂离子电池负极材料并制成扣式电池,通过电化学阻抗谱和倍率性能测试来研究硅材料体电阻率和掺杂类型对锂离子电池电化学性能的影响规律。结果表明,硅材料体电阻率越低,其储锂容量越高,倍率性能越好。电阻率相同时,n型掺杂硅始终比p型掺杂硅具有更大的储锂容量和更好的倍率性能。但是,当p型掺杂硅的电阻率远低于n型掺杂硅时,p型掺杂硅电化学性能更佳。另外,0.001Ω·cm的n型掺杂硅样品具有最佳的充放电比容量和倍率性能,其首次充放电比容量分别为457.7mAh·g^(-1)和543.4mAh·g^(-1)。n-Type silicon wafers with bulk electrical resistivity of 1Ω·cm,0.1Ω·cm,0.01Ω·cm and 0.001Ω·cm and p-type silicon wafers with bulk electrical resistivity of 1Ω·cm and 0.001Ω·cm were separately ball-milled to form six different types of silicon powders,which were subsequently mixed with graphite powders at a weight ratio of 5∶95 respectively in order for serving as anode materials in lithium-ion batteries（LIBs）.The effects of bulk electrical resistivity and doping types of silicon materials on the anodes＇ electrochemical performances in LIBs were investigated through the electrochemical impedance spectra and rate tests.The results showed that silicon with lower bulk electrical resistivity exhibits higher capacity and better rate performance.Besides,n-type doped silicon has higher capacity and better rate performance than those of p-type doped silicon with the same bulk electrical resistivity.In addition,if the bulk electrical resistivity of p-type doped silicon is much lower than that of n-type doped silicon,p-type doped silicon can perform better in electrochemical properties.The sample prepared from 0.001 Ω·cm n-type-Si wafer achieves the highest discharge and charge capacities（543.4 mAh·g^（-1） and 457.7 mAh·g^（-1）,respectively）during the first cycle.

关 键 词：硅/石墨负极 体电阻率 N型掺杂 P型掺杂 锂离子电池 电化学性能 

分 类 号：TM911[电气工程—电力电子与电力传动]