The Application Of Rotor-Stator Reactor In The Preparation Of Spinel Lithium Maganese Oxide Microsphere

The microsphere spinel LiMn2O4 is synthesized and the material is applied in Lithium-ion batteries as the cathode material. A two-step solid state method is introduced, while latest papers adopt a three-step solid state method, which is complex and hard to control the available conditions.The conditions of preparation of microsphere MnCO3 are researched and it is the first time to apply Rotor-stator Reactor in the preparation of microsphere MnCO3. Based on these conditions, microsphere MnCO3 is used as Manganese source to produce microsphere LiMn2O4 with Li2CO3 via solid state method. The products are characterized by XRD and SEM. The electrochemical property of LiMn2O4 is also investigated.At first, the conditions of preparation of microsphere MnCO3 are explored. The microsphere MnCO3 could be obtained from NaHCO3 and MnSO4 under these conditions:room temperature, rapid mixing,10ml ethyl alcohol is added in per 100ml MnSO4 solution and the male ratio between NaHCO3 and MnSO4 is 20:1. The concentration of reactants has close relationship with the diameter of microsphere LiMn2O4.A Rotor-stator Reactor is introduced to improve the mass transport between these two reactants, and the rotating speed, feed rate and reaction time is taken into consideration during this experiment. The microsphere MnCO3 synthesized by Rotor-stator Reactor presents uniform diameter and excellent dispersibility. The diameter of microsphere MnCO3 could be controlled through changing the concentration of reactants.As-prepared microsphere MnCO3 is used for the synthesis of microsphere LiMn2O4 via solid state method under 750℃. The morphology of LiMn2O4 has close bonds with the morphology of its precursor and the mole ratio between Li2CO3 and MnCO3 influence the electrochemical property of LiMn2O4. The lattice parameters could be used as a symbol to characterize the electrochemical property of LiMn2O4. LiMn2O4 with smaller lattice parameters presents better electrochemical property.The initial discharge capacity of Li rich material synthesized through Li2CO3:MnCO3=1:3 (mole ratio) could reach 132mAh/g, which is outweigh the figure in latest literature, and the figure could reserve 105mAh/g after 100 cycles under 0.1C.