Electrochemical exfoliation of graphene as an anode material for ultra-long cycle lithium ion batteries

Abstract

One of the key challenges in developing lithium ion batteries is the super-long cycles. Two-dimensional (2D) materials (especially graphene) with a layered crystal structure disclose many advantages and attract more interests in this field. Here we report a novel method through which the electrochemically exfoliated graphene (EG) is employed to construct an anode for ultra-long cycle Li-ion batteries. The high quality EG was directly sprayed onto the copper foil as a binder-free material, resulting in high conductivity, high volume capacity and bridging properties. The battery has exhibited a high capacity of 356 mA h g−1 at 1 A g−1, with ~100% capacity retention over 6500 cycles. This work demonstrates that the excellent graphene preparation process combined with binder-less spraying is effective strategy to significantly improve the cyclic stability of Li-ion batteries.