### 锂离子电池Sn30Co30C40三元合金负极材料的制备与性能研究

1. a 北京科技大学材料科学与工程学院 北京 100083;
b 上海空间电源研究所 上海 200245;
c 新能源材料与技术北京市重点实验室 北京 100083
• 投稿日期:2013-03-12 发布日期:2013-05-02
• 通讯作者: 解晶莹, E-mail: xiejingying2007@126.com;赵海雷, hlzhao@ustb.edu.cn. E-mail:xiejingying2007@126.com; hlzhao@ustb.edu.cn.
• 基金资助:

项目受国家基础研究(973, No. 2013CB934003);国家自然科学基金(21273019);上海市科技人才计划(No. 12XD1421900)和上海市科委科技创新项目(Nos. 10dz2250900, 12dz1200503)资助.

### Synthesis and Properties of Sn30Co30C40 Ternary Alloy Anode Material for Lithium Ion Battery

Liu Xina, Xie Jingyingb, Zhao Haileia,c, Wang Keb, Tang Weipingb, Pan Yanlinb, Feng Zhenheb, Lv Pengpenga

1. a School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083;
b Shanghai Institute of Space Power Sources, Shanghai 200245;
c Beijing Key Lab of New Energy Materials and Technology, Beijing 100083
• Received:2013-03-12 Published:2013-05-02
• Supported by:

Project supported by the National Key Basic Research Development Program of China (973 special preliminary study plan, No. 2013CB934003), the National Natural Science Foundation of China (No. 21273019), Shanghai Science and Technology Talent Project Funds (No. 12XD1421900) and Shanghai Science and Technology Development Funds (Nos. 10dz2250900, 12dz1200503).

With the development of advanced lithium ion batteries, electrode materials with higher capacity are urgently in demand. With respect to the anode materials, Sn-based alloy materials with high theoretical capacity (990 mAh/g) have the potential to replace the traditional, low capacity carbon-based materials. However, the practical application of Sn-based anode materials is severely retarded due to the poor cycling stability of electrode, which is believed to be caused by the pulverization of active particles resulting from the large volume of Sn during lithiation/delithiation process. The Sn-Co-C ternary alloy with amorphous or nano microstructure can overcome this problem and therefore display attractive electrochemical performance, including high capacity and good cycle stability. In the present work, amorphous Sn30Co30C40 alloy material was synthesized through a simple and scalable two-step method (carbothermal reduction-high energy ball milling method). CoSn2 alloy was firstly prepared by the carbothermal reduction route from low cost metal oxide and activated carbon. Then the prepared CoSn2 were mixed with metal cobalt and graphite in a molar ratio of 3:3:8 via a high energy ball milling process to synthesize the final Sn30Co30C40 material. The preferential synthesis of CoSn2 alloy was important to get Sn30Co30C40 material with much smaller CoSn grain dispersed in carbon matrix and thus critical to the better electrochemical performance. XRD, SEM, TEM, HR-TEM, S-TEM and electrochemical tests were used to evaluate the structure and electrochemical performance of the CoSn2 and Sn30Co30C40 materials. The synthesized Sn30Co30C40 material displayed micro-sized particle morphology, which in fact was composed of 10 nm CoSn grains distributed well in amorphous carbon matrix. The Sn30Co30C40 material showed high specific capacity of 550 mAh/g with an initial coulombic efficiency of 80%, good cycling stability and excellent rate-capability. The specific capacity of 430, 380, 280 mAh/g could be achieved at the rate of 1 C, 2 C and 5 C, respectively.