High-quality LiNi0.8Co0.15Al0.05O2 cathode with excellent structural stability: Suppressed structural degradation and pore defects generation

Although LiNi0.8Co0.15Al0.05O2 (NCA) cathode materials have been widely used for electric vehicles, the poor cycle performance still limits the further application. In this work, high-quality NCA with desired stoichiometric ratio and few structural defects is prepared by using N-methyl-2-pyrrolidone (NMP)- and urea-based solvothermal reaction. The as-prepared NCA exhibits high capacity (203 mAh g−1 at 0.1 C), excellent rate capability (117 mAh g−1 at 10 C, attributed to enhanced exposure of {010} planes), and good cycle performance (74.4% capacity retention at 300th cycle). Compared with NCA prepared by NaOH, NCA prepared by NMP and urea shows superior ability in suppressing structural degradation of R3‾m phase-to-Fd3‾m/Fm3‾m phase transformation, transition metal segregation, and pore defects generation after prolonged cycling, which can be used for ultrafast and long-lifespan lithium storage.