An integrated highly stable anode enabled by carbon nanotube-reinforced all-carbon binder for enhanced performance in lithium-ion battery

Abstract

Conversion and alloy-type anode materials suffer from large volume expansion during lithiation process, which causes the destruction of intact electrode structure and loss of efficient electrical contact between current collector and particles of anode material, resulting in fast capacity decay and poor cycling stability. Herein, a combined slurry-casting and heat-treatment approach has been adopted to prepare highly stable integrated anode composed of anode materials particles and all-carbon binder consisting of commercial carbon nanotubes (CNTs) and polyvinylidene fluoride (PVDF) derived carbon. This all-carbon binder shows a strong cohesive ability to copper current collector compared with traditional PVDF binder, and could effectively bind anode material particles and current collector. Moreover, CNTs reinforced all-carbon binder provides a robust mechanical and high conductive network to ensure structural stability of integrated anode, in which volume expansion of anode materials could be effectively suppressed during lithiation process. The integrated electrode with tin dioxide and silicon as active materials exhibits remarkable long-term cycling stability, maintaining 861.4 mA h g−1 after 500 cycles and 902.4 mA h g−1 after 300 cycles at 0.5C, respectively. This simple yet effective strategy is compatible with the traditional anode manufacture process, demonstrating its great potential in the practical use.