Novel carbon coated core-shell heterostructure NiCo₂O₄@NiO grown on carbon cloth as flexible lithium-ion battery anodes

Binding-free NiCo₂O₄@NiO@C/cc electrode was prepared by hydrothermal method, annealing method and physical vapor deposition. In this composite, NiCo₂O₄@NiO was strongly grown on carbon cloth and formed a core-shell heterostructure, which can facilitate the transport of ions. What's more, the conductivity was dramatically improved after coating NiO nanofalkes. Additionally, carbon coating can inhibit volume expansion, improve material conductivity and structural stability. The free-standing electrode material showed an initial capacity of 1885 mAh g⁻¹ at a current density of 100 mA g⁻¹, after 100 cycles, the reversible capacity stabilized around 1051 mAh g⁻¹ with Coulomb efficiency of 99.9%. At a high rate of 1600 mA g⁻¹, the capacity exhibited about 721 mAh g⁻¹, indicating that the NiCo₂O₄@NiO@C/cc composite is an outstanding material as the anode electrode material for flexible lithium-ion batteries with broad application prospect.