Simplified Spray Pyrolysis Synthesis Enabling a Novel Dual‐Doping Strategy for Ultrahigh‐Rate Ni‐Rich Cathode Materials for Lithium‐Ion Batteries

ABSTRACT Elemental doping has been extensively explored to address key challenges associated with Ni‐rich cathode material, such as Li/Ni cation mixing and anisotropic lattice strain, which hinder rapid Li ⁺ transport and accelerate mechanical degradation. However, single‐atom dopants typically improve only limited aspects of structural and electrochemical performance. In this study, we introduce a rational Zr─Ti co‐doping strategy via spray pyrolysis, in which Ti ⁴⁺ selectively modulates the local transition‐metal environment and the Ni oxidation state, while Zr ⁴⁺ strengthens the Ni‐rich lattice through robust Zr─O bonding. This synergistic doping suppresses detrimental phase transitions, stabilizes the oxygen sublattice, and mitigates microcrack formation, without aggravating Li/Ni disorder. To ensure homogeneous dopant incorporation, a spray pyrolysis approach utilizing Li‐containing precursor droplets was employed. This method offers uniform elemental distribution, simplified synthesis, and a reduced environmental footprint compared with conventional co‐precipitation techniques. As a result, Zr─Ti co‐doped Ni‐rich NCA microspheres (LiNi _0.85 Co _0.10 Al _0.04 Zr _0.007 Ti _0.003 O ₂ ) synthesized via short‐time, low‐temperature calcination, exhibit excellent high‐rate capability (161 mA h g ⁻¹ at 10C). This work demonstrates that integrating dual‐dopant chemistry with a scalable spray pyrolysis process offers a promising pathway to concurrently enhance rate performance and structural integrity, providing a generalizable framework for the next generation of Ni‐rich cathode materials.