Facile synthesis of Ni-NiO/C anode with enhanced lithium storage and long cycling life

A novel Ni-NiO embedded amorphous carbon (Ni-NiO/C) composite was synthesized by simple carbothermal reduction followed by low-temperature oxidation. Benefiting from the embedded metallic nickel, the Ni-NiO/C composite showed improved electrical conductivity and reduced electrochemical polarization when used as anode material of lithium-ion batteries. The Ni-NiO/C electrode can be reversibly discharged and charged for more than 1000 cycles at a high current density of 5 A g⁻¹, maintaining a discharge/charge capacity of ~ 335.9/335.8 mAh g⁻¹. When the current density returns from 5 to 0.25 A g⁻¹, the composite still exhibits a high reversible capacity of 751.9/747.6 mAh g⁻¹ at the 120th cycle. This work provides guidance to understand the impact of metallic particles on lithium storage.