• • W doping refines primary particle size and stacking, increasing average particle hardness from 68 MPa (PCNCM98) to 104 MPa (W-PCNCM98), a 1.5-fold improvement that suppresses microcrack formation during H2–H3 phase transition, directly addressing mechanical degradation in ultrahigh-nickel cathodes.
• • W-PCNCM98 achieves 73% capacity retention after 2000 cycles at 1 C and 25 °C in pouch full cells, a 54% relative improvement over PCNCM98, demonstrating enhanced cycling stability critical for EV longevity.
• • Thermal stability is improved: exothermic peak shifts from 190 °C (PCNCM98) to 203 °C (W-PCNCM98), with heat generation reduced from 1528 J g−1 to 1287 J g−1, mitigating safety risks from oxygen release.
• • W6+ doping suppresses transition metal dissolution and reduces leak current density in floating charge tests, indicating robust electrode–electrolyte interfacial stability, which is essential for long-term reliability.