Regulation Engineering of Alkali Metal Interlayer Pillar in P2-Type Cathode for Ultra-High Rate and Long-Term Cycling Sodium-Ion Batteries

Abstract

A novel “Na–Y” interlayer aggregate is proposed, which acts as a robust interlayer pillar, distinct from previously reported single-ion-based pillar structures. The coexistence of ordered and disordered Na⁺/vacancy states resulting from Cu/Y dual-site doping can stimulate rapid Na⁺ diffusion. The designed Na0.67Y0.05Ni0.18Cu0.1Mn0.67O2 electrode exhibits outstanding long-term cycling performance (~3000 cycles) and high-rate capability (~ 70 mAh g−1 at 50 C).