Characterization of multiple metals (Cr, Mg) substituted LiNi_(0.8)Co_(0.1)Mn_(0.1)O_2 cathode materials for lithium ion battery

摘要

Cr and Mg co-substituted LiNi_(0.5)Co_(0.1)Mn_(0.1)O_2 samples are synthesized by fast co-precipitation method and characterized by scanning electron microscope, X-ray diffraction, Rietveld refinement and electrochemical measurements. The Rietveld refinement results show that suitable Cr and Mg co-substitution could lead to synergistic reaction to form a kind of complementary structure, by full Cr occupying in Ni layer, and full Mg occupying in Li layer, respectively, and further attribute to highly ordered layered LiNi_(0.5)Co_(0.1)Mn_(0.1)O_2 with low cation mixing degree. Electrochemical studies demonstrate that Cr and Mg co-substitution in LiNi_(0.8)Co_(0.1)Mn_(0.1)O__2 also result in improved discharge capacity, initial coulombic efficiency, rate ability and cycling property compared to pristine LiNi_(0.8)Co_(0.1)Mn_(0.1)O_2. The improvements of electrochemical property resulted from the stabilized host structure by Cr and Mg incorporation into LiNi_(0.3)Co_(0.1)Mn_(0.1)O_2.