Development of a Synthesis Reactor with High Production Rate of Lithium Manganese Oxide Fine Particles

开发了一种利用流态化和喷雾热解相结合的系统从液体溶液中直接制备超细陶瓷粉末的新技术。在不同表观气速U_0=0.30~0.91m/S，前驱液浓度C_0=0.45~4.50mol/dm^3，静态床层高度L_S=50~150 mm的条件下，制备了最有前途的锂离子电池正极材料锂锰氧化物LiMn_2O_4。制备的样品为纯立方尖晶石结构，X射线衍射谱中没有任何杂质，制备的粉末的化学组成与前驱体溶液的化学组成一致。将制备的LiMn2O4粒子用作锂离子电池正极活性材料，并对Li/LiMn2C4电池的充放电性能进行了电化学研究。结果表明，在沸腾床中喷雾热解合成的LiMn2O4具有比传统喷雾热解和固相反应更好的放电容量和循环性能。

A novel technique has been developed to directly produce fine ceramics powders from liquid solution by a fluidized bed and spray pyrolysis hybrid system. Using this technique, the preparation of lithium manganese oxides LiMn_2O_4, which are the most promising cathode materials for lithium ion battery, has been carried out for various superficial gas velocities U_0=0.30-0.91 m/s, concentrations of precursor solution C_0=0.45-4.50 mol/dm^3 and static bed heights L_s=50-150 mm. The as-prepared samples exhibited a pure cubic spinel structure without any impurities in the XRD patterns, and the chemical composition of as-prepared powders showed in a good agreement with the one of precursor solution.The as-prepared LiMn_2O_4 particles were used as cathode active materials for lithium-ion battery and electrochemical studies were carried out on the charge/discharge characteristics of the Li/LiMn_2C_4 cells. As a result, the LiMn_2O_4 particles, synthesized by the spray pyrolysis in a fluidized bed reactor, exhibited better discharge capacity and cycling behavior than those by the conventional spray pyrolysis and solid state reaction.