Three-dimensional porous composite framework assembled with CuO microspheres as anode current collector for lithium-ion batteries

Abstract

The surface structure and material composition of current collectors have significant effects on the electrochemical performances of lithium-ion batteries (LIBs). In this work, a three-dimensional (3D) porous composite framework is applied as the anode current collector in LIBs. This unique 3D skeleton is composed of conductive carbon fiber/Cu core/shell fibrous structure. With an oxidation treatment upon the copper shell, the porous framework is assembled with CuO microspheres. Using mesocarbon microbead (MCMB) graphite powders as the active material, the cell with this 3D porous composite current collector shows an improved reversible discharge-charge capacity of 415 mAh g–1 at a current rate of 0.1 C after 50 cycles, which is much higher than that of the cell with a flat Cu foil ( 127 mAh g–1 ). It is demonstrated that this unique fibrous network of the 3D current collector coupled with the morphological effects of the CuO microspheres greatly improve the cell performance in terms of electrical conductivity, reversible capacity and cycling stability.