Regulating Mechanical Fractures and Surface Reactivities to Achieve High Electrochemical Stability in Ni‐Rich Cathodes With Boron and Tin

Nickel‐rich layered oxides (LiNi x Co y Mn 1‐ x ‐ y O 2 , x > 0.8) are leading cathode materials for high‐energy‐density lithium‐ion batteries (LIBs). However, mechanical fracturing at both intergranular and intragranular levels, induced by anisotropic lattice strain during phase transitions at high states of charge, together with surface reactions between the cathode and electrolyte, leads to severe capacity fading during prolonged cycling. In this study, the codoping effect of boron (B) and tin (Sn) on the battery performance of the Ni‐rich cathode material, specifically Li(Ni 0.92 Co 0.03 Mn 0.05 )O 2 , is scrutinized with a focus on enhanced structural stability and conductivity. The synergistic B–Sn codoping markedly improves cycling stability, achieving 86.9% capacity retention after 150 cycles. Our findings highlight that a dual‐dopant strategy enabling simultaneous regulation of mechanical integrity and surface reactivity presents a promising pathway toward the development of next‐generation, high‐performance Ni‐rich cathodes for LIBs.