Manufacture Of Lithium Ion Battery Based On New-Typed Lithium Iron Phosphate Nanomaterials

Among various alternative cathode materials, lithium iron phosphate (LiFePO4) is gaining significant attention because of its high specific capacity (170mAh/g), excellent cycling performance, thermal stability, safe nature, low cost and environmentally benign. Presently, research on LiFePO4is focused on the morphology of particles or nanoparticles. It is an important and meaningful subject of study to fabricate one-dimensional structured LiFePO4nanomaterials, to assemble and to determine the performances of lithium ion battery.In this thesis, LiFePO4/C nanofibers, nanobelts, LiFePO4/C nanofibers loaded with Ag nanospheres, LiFePO4/C hollow nanofibers and LiFePO4@Ag nanofibers were synthesized by electrospinning. The samples were characterized by XRD, SEM, TEM and BET specific surface area analyzer. The results showed that the mean diameter of LiFePO4/C nanofibers was179.08±29.66nm, the average width and thickness of the nanobelts were2.50±0.33μm and162nm, respectively. The average diameter of LiFePO4/C hollow nanofibers was171.78±29.02nm. Among the samples, LiFePO4/C hollow nanofibers have the largest BET specific surface area which was reached up to98.66m2/g.The galvanostatic charge and discharge test showed that at a current rate of0.2C, coin cells containing LiFePO4/C nanofibers, nanobelts and hollow nanofibers exhibit the initial discharge capacity of133.6mAh/g,123.38mAh/g and114.81mAh/g, respectively. The discharge plateau was ca.3.4V. All the cells exhibit an excellent cycling stability without obvious capacity fading after50cycles.