钴掺杂Mn3O4作为模板制备锂离子电池正极LiMn2O4

以水热合成的钴掺杂Mn₃O₄作为模板，通过固相反应制备尖晶石LiMn₂O₄。XRD谱图和SEM照片显示制备的LiMn₂O₄具有岩石状结构并呈现良好的结晶性，同时Co的引入能够引起LiMn₂O₄晶格的收缩。作为锂离子电池正极材料，Co含量的增加能够提高循环稳定性但降低材料放电比容量，3% Co掺杂的LiMn₂O₄在0.5 C的电流密度下，经过100次循环后，剩余放电比容量达101.6 mAh·g^-1；在10 C的电流密度下，放电比容量可维持在81.0 mAh·g^-1，优于未掺杂的LiMn₂O₄。这是由于Co的引入能够稳定LiMn₂O₄晶体结构并抑制循环中的姜-泰勒扭曲。

SYNTHESIS OF Li-ION BATTERY CATHODE LiMn2O4 FROM Co DOPED Mn3O4

Spinel LiMn₂O₄ have been prepared by solid state reaction using Co doped Mn₃O₄ as template. XRD patterns and SEM images show that the LiMn₂O₄ with rock-like morphology has excellent crystallinity, and the introduction of Co results in the lattice shrinkage of LiMn₂O₄. As the cathode materials of lithium ion battery, the increase of the Co contents will decrease of the discharge capacity accompanying with the improvement of cycling stability. 3% Co doped LiMn₂O₄ can retain a discharge capacity of 101.6 mAh g^-1 after 100 cycles at a current density of 0.5 C, and a capacity value of 81.0 mAh·g^-1 can be maintained even at a high rate of 10 C. The overall electrochemical performances of 3% Co doped LiMn₂O₄ are better than that of bare LiMn₂O₄. The increased stability of LiMn₂O₄ and decreased Jahn-Teller distortion during cycling, resulting from Co doping, may be responsible for the improvements.