Optimize solid‐state synthesis ofP2‐Na0.67Ni0.33Mn0.67O2cathode materials by using the orthogonal experimental design method

The P2-Na0.67Ni0.33Mn0.67O2 cathode materials were acquired by convenient solid-state method; the preparation conditions and electrochemical performance of materials were studied in this article. The optimal synthesis parameters are systematically studied via orthogonal experiments. The synthesis conditions, including factors of the excess Na content, calcination temperature, and calcination time, were optimized based on an orthogonal experimental design. Orthogonal experiment shows that the excess Na content has the greatest influence on the discharge capacity of the P2-Na0.67Ni0.33Mn0.67O2 materials. And the optimal technological parameters are determined as follows: the excess Na content of 3%, the calcining temperature of 900°C, and calcining time of 10 hours. The microstructure of the material was observed by scanning electron microscope (SEM) and transmission electron microscope (TEM), and then, we discussed the influence of different synthesis conditions on the microstructure of the material. Through the study of the electrochemical properties of P2-Na0.67Ni0.33Mn0.67O2 samples, we know that materials have good initial discharge capacity (159.3 mAh g−1) and excellent rate performance.