以氯化钴、氯化铝溶液精确配制的双元液为原料，碳酸氢铵溶液为沉淀剂，采用共沉淀合成法、干燥煅烧一体化工艺制备掺铝小粒径的四氧化三钴，将不同掺铝量的四氧化三钴和碳酸锂按照相同的比例混匀煅烧制备钴酸锂。研究不同铝含量掺杂四氧化三钴的均匀性对高容量电池循环和倍率性能的影响。XRD、SEM、表面和剖面EDS测试表明：掺铝0.2%的四氧化三钴表面和剖面铝分布最为均匀，表面一次颗粒最为细小，无条状晶型。电化学测试表明：掺铝均匀的小粒径四氧化三钴能改善正极材料的高容量性能及提高材料的循环性能。其中0.2%铝掺杂四氧化三钴制备的钴酸锂具有优异的循环寿命和倍率性能，1 C倍率下的首次放电容量为198.0 mAh/g,100次充放电后的放电容量仍为195.0 mAh/g，容量保持率为96.5%，以及0.2 C、0.5 C、2 C、3 C、5 C等不同倍率下的放电容量均明显优于不同掺杂量的正极材料。

Bimetallic raw materials composed of cobalt chloride solution and aluminum chloride solution, ammonium bicarbonate solution as the precipitating agent, the small-sized doped of aluminum Co_3O₄ was prepared for the co-precipitation method and high-temperature calcination, the Co_3O₄ about different aluminum doping and Li₂ CO₃,mixed evenly with Li₂ CO₃ and calcined to prepare for Al-Li₂ CoO₂. The study investigated the effect of the uniformity of Co_3O₄ doped with different aluminum contents on the battery cycling performance. XRD, SEM, surface and cross-sectional of EDS tests showed that doping of 0.2% aluminum Co_3O₄ had the most uniform aluminum distributionon its surface and cross-section, with the finest primary particles on the surface and no presence of striped crystal patterns. The electrochemical tests indicated that small-particle-sized cobalt tetroxide with uniform aluminum doping improved the high-capacity characteristics of the cathode materials and enhanced their cycling performance. Among of them, lithium cobaltate prepared with 0.2% aluminum doping demonstrated superior cycling life and rate performance, exhibiting a first discharge capacity of 198.0 mAh/g at 1 C, a discharge capacity of 195.0 mAh/g after 100 cycles, a capacity retention rate of 96.5%, and significantly better discharge capacities at different rates, such as 0.2 C, 0.5 C, 2 C, 3 C, and 5 C compared to cathode materials with varying doping levels.