Porous CoFe2O4 nanowire arrays on carbon cloth as binder-free anodes for flexible lithium-ion batteries

Abstract A three-dimensional CoFe2O4 nanowire array on carbon cloth was fabricated with a hydrothermal method together with a post-annealing treatment. As a binder-free and flexible anode material for LIBs, it showed an improved electrochemical performance with high cycling stability and excellent rate capability. It exhibited an initial discharge capacity of 1615 mAh g−1 and retained a reversible capacity of about 1204 mAh g−1 after 200 cycles at a specific current of 500 mA g−1. The high capacity, outstanding rate performance and cycling stability can be attributed to the special configuration of hierarchal porous CoFe2O4 nanowires on carbon cloth, which possess many advantages like short diffusion length, easy strain relaxation and fast electron transport. Moreover, the integrated CoFe2O4 nanowires/carbon cloth electrode shows high flexibility and high areal capacity (2.41 mAh cm−2), which makes it suitable for use as a binder-free anode to build flexible LIBs.