Composite Technology To Prepare Lithium-ion Battery Cathode Materials Of Limn <sub> 2 </ Sub> O <sub> 4 </ Sub>,

Due to its high cell voltage, low cost and environmental friendliness, LiMn₂O₄ is considered as the most promising cathode material for Li-ion battery. However, the capacity fading during cycling hinders their commercial applications. To improve the electrochemical performance of LiMn₂O₄, a composite technique that combined the optimization of synthesis, adulteration and surface modification together was used in this article.The main work of the research was as follows:(1) Co, which is smaller than Mn and has the strong bond energy of Co-O, is used as the adulterant to synthesize LiCoo.1Mn1.9O4 by soft chemical method. The adulterant of Co can stabilize the structure and prohibit the Jahn-Teller effect in LiMn₂O₄. The results showed that LiCo_0.1Mn_1.9O₄ had good electrochemical performances.(2) Using the organic materials that could be dissolved into water as the raw materials, C was homogeneously coated on LiMn₂O₄ and LiCo_0.1Mn_1.9O₄. In this way, C effectively prohibited the direct contact of LiMn₂O₄ with the electrolyte, which slowed the dissolution of Mn and improved the electrochemical performances of LiMn₂O₄ The new method provided a non-pollution and easy way for the industrialization of LiMn₂O₄.(3) H₃BO₃ was modified on LiMn₂O₄ by successive isochronical annealing method. But, solid solutions formed from the reaction of H₃BO₃ with spinel decreased the cyclic property of LiMn₂O₄.