Preparation Of Transitional Metal Oxide Nanomaterials And Their Applications In Lithium-ion Battery

Lithium-ion batteries (LIBs), owing to their high energy density, light weight, long cycle life, have attracted a lot of researchers and enterprises, and have shown considerable potential for energy storage device. The successful utilization of LIBs depends strongly on the preparation of nanomaterials with outstanding lithium storage properties. As the popularity of mobile phones, tablet PC, digital camera, electric bicycles, and other small or medium-sized electronics, as well as electric cars, large extension, in the performance and safety of LIBs put forward higher requirements. Nowadays carbon anode materials is widely used, but it can't meet the needs of next-generation LIBs'anode material in many respects, therefore, the development of new high specific capacity, high security, high stability, low-cost lithium-ion battery anode material is particularly urgent. Compared with conventional carbon anode material, transition metal oxide materials have higher capacity, and the energy density is 5 to 7 times of the theoretical capacity of carbon materials which is widely used at present. What's more, it can withstand high power discharge meet power tool batteries and battery needs. The current common transition metal oxide electrode materials include Fe2O3, Fe3O4, TiO2, Mn2O3, Mn3O4, and so on, but because they are low initial coulomb efficiency, low high-rate charge and discharge capacity and cycle stability is poor and other deficiencies that limit its wider application.Therefore, how to adopt simple method step tosynthesis of new composite transition met al electrode materials will be a very meaningful research subject. So this paper carried out the iron oxide and tin doped manganese carbonate composite iron ox ide nanorods preparation, characterization and electrochemical performance of the research, a nd the compound and doping nano material effect on the electrochemical properties are discus sed:First, we used FeCl3, MnCl2 and urea to synthesis rhombohedral a-Fe2O3/MnCO3 composite nanoparticles by one-step hydrothermal process under alkaline conditions. At the constant current density of 200 m/g, nanoparticles displayed 1640 mAh/g discharge capacity at first cycle. The reversible capacity maintained 527 mAh/g after 100 cycles. Both exhibited high specific capacity and good cycling performance, which were promising anode materials for LIBs.Second, we prepared Sn doped Fe2O3 nanorods by one-step hydrothermal method without surfactants. The nanorods have excellent dispersion performance. Discharge capacity has reached 1260 mAh/g at the first cycle. After 100 cycles, the reversible capac-ity remained 952.5 mAh/g. Moreover, it showed excellent rate capability and overcomed the shortcoming of pure Fe2O3 cycle performance and rate capability, it is an excellent anode material for LIBs.