1. School of Metallurgy and Environment, Central South University, Changsha 410083, P. R. China
2. Engineering Research Center of the Ministry of Education for Advanced Battery Materials, Central South University, Changsha 410083, P. R. China
3. Hunan Provincial Key Laboratory of Nonferrous Value-Added Metallurgy, Central South University, Changsha 410083, P. R. China
4. National and Local Joint Engineering Laboratory for Lithium-ion Batteries and Materials Preparation Technology, Key Laboratory of Advanced Battery Materials of Yunnan Province, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China