Triphase electrode performance adjustment for rechargeable ion batteries

Triphase composite-structure materials Na2/3Ni1/3−xFexTi2/3O2 (0 ≤ x ≤ 1/3) were designed and studied by advanced in-situ XRD techniques. Tunnel-Na2.65Ti3.35Fe0.65O9, P2-Na2/3Ni1/3Ti2/3O2, and tunnel-NaFeTiO4 structures are balanced for electrochemical performance. In addition, better long-term performance for this material can be achieved by adjusting the proportion of these three structures.226