Preparation of Li4Ti5O12 Nanosheets/Carbon Nanotube Composites and Application of Anode Materials for Lithium-Ion Batteries

Abstract

ABSTRACT: Li4Ti5O12 nanosheets (LTO NSs)/carbon nanotubes (CNTs) composites are synthesized using a facile, reproducible, and scalable strategy. In the hydrothermal process, the introduction of CNTs significantly improves the rate performance of LTO NSs. The incorporation of CNTs into the LTO NSs forms a delicate conductive network for rapid electron and lithium ions transport, resulting in excellent rate performance and superior cycling performance. LTO NSs/7.5%-CNTs composites show the highest reversible capacity and high-rate capability (a reversible capability of 157, 145, 132, 118, and 105 mA h g-1 at 1, 2, 3, 4, 5 A g-1, respectively) with good cycling performance (approximate 6.9% capacity loss after 1000 cycles at 2 A g-1 with a capacity retention of 135 mA h g-1), which is apparently larger than pristine LTO NSs. The significantly improved rate capability and cycling performance of the LTO NSs/CNTs composites are mainly attributed to their the lower polarization of potential difference, the larger diffusion coefficient of lithium ion and smaller charge-transfer resistance than pure LTO NSs. Keywords: Lithium titanate nanosheets; Carbon nanotubes; Rate performance; Lithium ion diffusion; Lithium ion batteries References [1] Y.-Q. Wang, L. Gu, Y.-G. Guo, H. Li, X.-Q. He, S. Tsukimoto, Y. Ikuhara, L.-J. Wan, Rutile-TiO2 Nanocoating for a High-Rate Li4Ti5O12 Anode of a Lithium-Ion Battery, J. Am. Chem. Soc. 134 (2012) 7874-7879. [2] G. Xu, W. Li, L. Yang, X. Wei, J. Ding, J. Zhong, P. Chu, Highly-crystalline ultrathin Li4Ti5O12 nanosheets decorated with silver nanocrystals as a high-performance anode material for lithium ion batteries, J. Power Sources 276 (2015) 247-254. [3] B. Li, C. Han, Y.-B. He, C. Yang, H. Du, Q.-H. Yang, F. Kang, Facile synthesis of Li4Ti5O12/C composite with super rate performance, Energy Environ. Sci. 5 (2012) 9595-9602. Acknowledgements This work was financially supported by the National Natural Science Foundation of China (Grant No. 21273195, 21511140282), a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions. The work was also sponsored by Qing Lan Project of Higher Learning Institutions in Jiangsu Province, the support of high-end talent plan of Yangzhou university, and Jiangsu Key Laboratory of Environmental Material and Environmental Engineering (K11032). The authors also acknowledge the Testing Center of Yangzhou University for SEM, TEM, XRD, and Raman experiments.