نبذة مختصرة : Introduction: Cathode is an important component in the performance of Li-ion batteries. Various compounds have been used as cathodes in Li-ion batteries, among which NCA (LiNi0.8Co0.15Al0.05O2) has attracted a lot of attention due to its high specific capacity and capacity retention. However, the applied reversible capacity is lower than the theoretical value, which is because of the migration of Ni cation to the Li layer (cation mixing). Therefore, proper synthesis of this structure can help to increase the capacity and battery lifetimeMethods: In this research, the precursor of Ni0.8Co0.15Al0.05(OH)2 were synthesized by co-precipitation method using ammonia as complexing agent at the temperature and pH of 60˚C and 12 and then NCA cathode powder was obtained by solid state method and calcination and sintering at 550 and 800˚C respectively, under oxygen atmosphere. For comparison, the synthesis of Ni0.8Co0.15(OH)2 and then addition of aluminum hydroxide by solid state method was done. The effects of synthesis method and time were studied.Findings: Results showed that in the sample with a synthesis time of 4 days and then 2 sintering stages, anodic and cathodic peaks in cyclic voltammetry can be seen clearly. Besides, better capacity and capacity retention, lower charge resistance, and higher Li diffusion were achieved.Conclusion: Results indicate that ammonia as a complexing agent in co-precipitation synthesis is suitable for the Al ion. Moreover, increasing the synthesis time helps to have complete layered structures, which is followed by better capacity. Two times sintering is also effective in reducing the cation mixing.
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