Novel 3D Nanocarbon Electrodes for High-Rate Li-Ion Batteries

Abstract

Portable electronic devices are negatively impacted by power density limitations of current Li-ion batteries (LIBs). Architectures or materials for faster ion and electron transport are required. Graphene-based electrodes with a 3D hierarchical structure have shown promise in LIBs due to their short ion diffusion distance, excellent electrical conductivity and high surface area. However, techniques for fabricating such hierarchical nanostructures with textural properties that can be easily tailored are still complicated and not fully developed. In this work, a low cost, green, facile, controllable and scalable approach for the fabrication of 3D hierarchical graphene-based electrodes is proposed. The 3D hierarchical structures with adjustable pores and nanowrinkles are prepared from graphene oxide or chemically functionalized graphene sheets via a wet chemical method using polymeric micro-gels as the template. The resulting 3D graphene electrodes have been used as a model 3D electrode system to establish correlations between the 3D properties (surface chemistry, defect density and textural properties) and the LIB performance (rate capability, energy capacity and durability).