JOURNAL OF POWER SOURCES, cilt.672, ss.1-13, 2026 (SCI-Expanded, Scopus)
The pursuit of high-electrochemical-performance cathodes demands precise control over synthesis to manage stability-performance trade-offs. Here, we present a systematically optimized sol-gel-assisted solid-state method for synthesizing aluminum and zirconium co-doped high-nickel layered oxide containing cobalt and zinc (LiNi0.8Co0.05Zn0.05Al0.08Zr0.02O2), achieving a structure with minimized cation disorder. Electrochemical investigation reveals that the co-doped cathodes exhibit a remarkable initial discharge capacity of 214.7 mAh/g with good long-term cycling performance in the 2.7-4.4 V electrochemical window. However, Cyclic Voltammetry (CV) and rate performance tests reveal a critical performance trade-off. While co-doping enhances structural stability through a dual bulk and surface mechanism, it promotes the formation of tightly fused primary particles and a dense, low-porosity architecture. This morphology significantly constricts available electrolyte
diffusion pathways, although intrinsic ionic diffusivity is improved, Li+ ions must navigate extended distances through the secondary particle bulk. This increased diffusion length results in a substantial reduction in CV peak currents, ultimately limiting rate capability. These findings underscore that optimizing powder morphology through fine-tuned dopant concentrations is essential to balancing the stability-rate trade-off in future high-energy cathode designs.