| 초록 |
Alien atom doping has been adopted to modify the electrochemical performance of olivine type LiFePO4 for cathode material of the LIB. Here, we first report that transition-metal-doped (T=Fe,Co,Mn, La and Ce) cathode material synthesiztion for Li-Ion batteries. The results showed that they can improve the electrochemical performance of LiFePO4, the effects of T-doping have been studied by the measurements of X-ray diffraction pattern, Raman shifts and Scanning Electronic Microscopy (SEM) as sample characterizations. Li ion migration dynamics of doping systems are investigated from first principles calculations and also vacancy mediated Li migration and interstitial Li migration are considered. The vacancy formation energies and the site energies of the interstitial Li are calculated in advance in order to figure out reasonable migration pathways. Results shown that Li vacancy diffusion in the bulk phases can be fast, while the intrinsic vacancy formation is difficult. |
