▎ 摘　　要

Sodium-ion batteries (SIBs) have gained more and more interest for grid-level energy storage applications compared with current lithium-ion batteries (LIBs). In this paper, well-uniform and dispersed spindle-shaped NiCo2O4 particles were synthesized by solvothermal method, and then grapheneencapsulated NiCo2O4 (NiCo2O4@G) was formed core-shell nanostructures, which greatly enhanced the electronic and ionic (electro-active) conduction and also effectively buffering to accommodate the strain. Benefit from its structure feature, the prepared NiCo2O4@G core-shell nanostructures composite shows good cycling with a capacity of up to similar to 400 mAh g (1) (100 mA g (1)) in 100 cycles for NIBs anode. The facile synthesis process and excellent SIBs behaviors in this paper are expected to be extended in developing other anode materials in battery system. (C) 2017 Elsevier B.V.All rights reserved.