Co-doped Li4Ti5O12 nanosheets with enhanced rate performance for lithium-ion batteries. (10th October 2017)

• Record Type: Journal Article
• Authors: Liang, Qiu; Cao, Ning; Song, Zhonghai; Gao, Xuejiao; Hou, Lina; Guo, Tirong; Qin, Xue
• Is Part Of: Electrochimica acta. Volume 251(2017)
• Page Start: 407
• Page End: 414
• Publication Date: 2017-10-10
• Subjects: Co2+-doped Li4Ti5O12 -- High rate performance -- Good electrochemical reversibility -- Lithium ion batteries; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2017.08.121
• Languages: English
• ISSNs: 0013-4686

Abstract

Highlights: Li4 Ti5 O12 and Co 2+ -doped Li4 Ti5 O12 nanosheets are prepared and investigated in LIBs. A capacity of 112.6 mAh g −1 for the Li4 Ti4.85 Co0.15 O12 electrode is obtained in LIBs at 50C. A capacity of 150.8 mAh g −1 (95.1% retention) for the Li4 Ti4.85 Co0.15 O12 electrode is obtained in LIBs at 5C after 3000 cycles. Abstract: Co 2+ -doped Li4 Ti5 O12 (LTO) in the form of Li4 Ti5-x Cox O12 (x = 0, 0.10, 0.15, 0.20) is prepared using a facile hydrothermal method. The doping of Co 2+ leads to a decrease of the charge transfer resistance and improvement of the lithium ion diffusion coefficient. The as-prepared samples, Li4 Ti5-x Cox O12 (x = 0.15) exhibits the best cycling stability and rate capability as anode material for lithium ion batteries, which delivers the initial specific capacity of 168.3, 163, 159, 156.4, 145.9, 140.4, 130.9 and 112.6 mAh g −1 at 1, 2, 5, 10, 15, 20, 30 and 50C (1C = 175 mAh g −1 ) rate in the voltage range of 1.0-2.5 V respectively, and a discharge capacity of 109.3 mAh g −1 after 1000 cycles at 50C. In addition, it keeps a discharge capacity of 150.8 mAh g −1 (95.1% retention) at 5C even after 3000 cycles. Therefore, Co 2+ doping technique provides an effective approach to improve electrochemical performances of LTO.