Role of moderate strain engineering in Nickel Sulfide anode for advanced sodium-ion batteries

The lattice strain engineering of sodium storage materials is of great significance for developing reliable sodiumion batteries (SIBs). Lattice strain engineering controls the structural evolution during sodium ion insertion/ extraction and minimizes the aggregation of active material and volume expansion during cycling. Herein, the ball milling technique is used to tune the lattice strain of NiS nanocomposite, which was later employed as anode material in SIBs. The structurally tuned anode exhibits high sodiation capacity, good rate capability (495.7 mAh g-1 at 0.2 A g-1, 383.2 mAhg- 1 at 15 Ag-1), and exceptional cycling performance (16,000 cycles at 5 A g-1). Significantly, introducing a considerable amount of moderate strain into the structure by the ball milling technique, researchers can solve the problem of structure instability, volume expansion, and high-capacity loss of the electrode materials during repeated cycling. Therefore, lattice strain engineering using ball milling is a potential approach that may open the door to more sustainable and functional SIBs.