Preparation And Electrochemical Performance Of Nano-sized Limn₂O₄and Lini_0.5Mn_1.5O₄

LiMn2O4and LiNio.5Mn1.5O4has the extremely application prospect of lithium ion battery anode materials, and Nano-sized materials will significantly improve the electrochemical performance.This paper firstly using the theory of complex oxide, established a nanometer single crystal Mn3O4rapid preparation technology. Established process method, the use of manganese ion in the alkaline ammonia complexation of ethanol solution, directly to the bivalent manganese ion complex oxide to Mn3O4solid particles (4.5nm), and avoid the traditional wet method for manganese hydroxide of the intermediate filtration of Mn3O4, beating, oxidation and other steps. Process for gas liquid reaction, the reaction rate than traditional wet method of gas-solid reaction rate greatly improved, the preparation time of Mn3O4is reduced from the traditional several hours to five minutes.On this basis, the homemade Mn3O4as raw material, the preparation of the kinds of lithium ion battery cathode material:nano LiMn2O4and nano LiNio.5Mn1.5O4two, and through XRD, SEM/TEM, electrochemical test methods such as the performances have been characterized. The as-synthesized LiMn2O4nanoparticles with the average particle size of about24rm. The cycle performance of LiMn2O4/Li cells with0.5C of discharge rate at room temperature shows good cycle performance initially delivers135.4mAh·g-1and retains91.4mAh.g-1(79.2%) at the300th cycle, and with the discharge capacities of133mAhg-1and90mAh.g-1at rates of0.1C and2C. The nanosized LiNi0.5Mn1.5O4prepared by the new method is made up of many three-dimensional nanoscale particles, with the average particle size of about80-100nm. The cycle performance of LiNi0.5Mn1.5O4/L1cells with0.5C of discharge rate at room temperature shows good cycle performance initially delivers128mAh·g*1and retains108mAhg-1(84.4%) at the250th cycle and the nanoscale granular LiNi0.5Mn1.5O4spinels exhibits discharge capacities of131mAhg-1and118mAh.g-1at0.2C and2C rates, respectively.The preparation technology of nano Mn3O4, nano LiMn2O4and nano LiNi0.5Mn1.5O4has a simple process and easy to industrialization.