A flexible copper sulfide @ multi-walled carbon nanotubes cathode for advanced magnesium-lithium-ion batteries

• Published in: Journal of colloid and interface science 2019-10, Vol.553, p.239-246
• Main Authors: Zhang, Yali, Li, Yong, Wang, Yong, Guo, Rui, Liu, Wen, Pei, Haijuan, Yin, Geping, Ye, Daixin, Yu, Shengxue, Xie, Jingying
• Format: Article
• Language: English
• Subjects: Copper sulfide; Flexible; Magnesium-lithium-ion batteries; Multi-walled carbon nanotubes
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2019.06.027

The flexible F-CuS-CNT electrode exhibits improved electrochemical performance in Li-Mg hybrid battery, which is ascribed to the stable electrode structure and excellent conductive network. [Display omitted] The hybrid magnesium-lithium-ion batteries (MLIBs) are promising alternatives in large-scale energy storage field owing to low cost and high safety of magnesium batteries and fast diffusion rate of Li-ion in the electrode. Herein, a free-standing and binder-free copper sulfide/Multi-walled carbon nanotubes film cathode (F-CuS-CNT), along with Mg-Li dual-salt electrolyte and dendrite-free Mg anode, is employed to construct the MLIBs. At room temperature (25 °C), the F-CuS-CNT electrode with a CuS content up to 70% exhibits a high initial specific capacity of 479 mAh g−1 (∼85.5% of the theoretical capacity) and a considerable cycling stability (165 mAh g−1 even after 100 cycles at the current density of 30 mA g−1), which far surpasses those of conventional CuS electrode. The excellent electrochemical performances of the F-CuS-CNTs electrode can be attributed to its excellent flexible network architecture as well as abundant pores, which provide more stable conductive buffering layers for CuS particles and higher Li+ diffusion dynamics during the charging/discharging process. This work demonstrates that constructing a flexible and free-standing film electrode could improve the electrochemical performances of MLIBs and may be an appropriate select of preparing flexible MLIBs.