1. Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources; Qinghai Institute of Salt Lakes, Chinese Academy of Sciences; Xining 810008 PR China) Fax: (+86)-971-6306002
2. Key Laboratory of Salt Lake Resources Chemistry of Qinghai Province; Xining 810008 PR China
3. University of Chinese Academy of Sciences; Beijing 100049 PR China
4. Qinghai Research Center of Low-temperature Lithium-ion Battery Technology Engineering; Qinghai Lvcaodi New Energy Technology Co. Ltd.; Xining 810000 PR China
5. Central South University; Changsha 410083 PR China