Facile fabrication of NiO flakes and reduced graphene oxide (NiO/RGO) composite as anode material for lithium-ion batteries

A NiO flake and reduced graphene oxide sheet (NiO/RGO) composite was synthesized via an in situ ultrasonic agitation method after heat calcination in a nitrogen atmosphere. The NiO/RGO composite displayed a high reversible capacity of 825 mA h/g after 50 cycles at 100 mA/g, which was higher than the pure NiO flakes (197 mA h/g). The RGO sheets (115 mA h/g) used in lithium-ion batteries as anode materials. The NiO/RGO electrode showed excellent rate capacities that were higher than the pure NiO flakes and the RGO sheets electrodes within the same experimental conditions. These improvements could be attributed to the RGO sheets improved the electrical conductivity of NiO flakes and buffered the volume expansion of the NiO/RGO composite electrode during lithium cycling.