One-Step Synthesis of Carbon Nanotubes-Modified and Carbon-Coated Li4Ti5O12 and Its Application to Li Half Cell and LiNi0.8Co0.1Mn0.1O2/Li4Ti5O12 Full Cell

• Published in: Journal of electronic materials 2020-04, Vol.49 (4), p.2529-2538
• Main Authors: Zhang, Pengfei, Liu, Yanxia, Chai, Fengtao, Fan, Yameng, Hou, Aolin
• Format: Article
• Language: English
• Subjects: Carbon; Carbon nanotubes; Characterization and Evaluation of Materials; Charge transfer; Chemistry and Materials Science; Coating; Composite materials; Diffusion coefficient; Diffusion rate; Electrochemical analysis; Electron conductivity; Electronics and Microelectronics; Instrumentation; Lithium; Lithium ions; Materials Science; Optical and Electronic Materials; Solid State Physics
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-020-07962-w

Li 4 Ti 5 O 12 (LTO) composites modified with carbon nanotubes (CNTs) and carbon coating (LTO@C/CNTs) were synthesized by a simple solid-state reaction. The carbon-coated layers reduce the growth of the primary particles, inhibit interface side reactions and increase electron conductivity, so CNTs-modified LTO can form a conductive network and improve the diffusion path of lithium ions. The LTO@C/CNTs composites show a high-rate capability (150 mAh g −1 at 10 C, 145 mAh g −1 at 20 C) with good cycling performance (90.1% and 82.8% capacity retentions after 1000 cycles at 10 C and 20 C, respectively). In addition, superior electrochemical performance is also demonstrated in a full cell with a LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) cathode and LTO@C/CNTs anode (97.1% capacity retentions after 200 cycles at 1 C). The carbon coating and CNTs-modified in LTO can reduce the polarization of potential difference and charge-transfer resistance, improve the diffusion coefficient of lithium ions, and lead to high rate performance and cycle stability.