锂离子电池背景介绍及研究进展.ppt

锂离子电池背景介绍及研究进展 锂离子电池背景介绍及研究进展 Recent developments in cathode materials for lithium ion batteries Review Cathode materials Composite cathodes Effect of doping Introduction Cathode performance Effect of microstructure and morphology Conclusions 1 1. Introduction battery performance electrode material Lithium-ion batteries：widely utilized Future：light weight,small volume, high energy density, safety cathode materials 2. Cathode materials LiCoO2：α-NaFeO2 structure，commonly used，more costly，less stable，rapid decrease； LiNiO2：α-NaFeO2 structure，lower in cost, higher energy density, less stable，less ordered; LiMnO2：monoclinic structure，less ordered; Li(Ni1/3Mn1/3Co1/3)O2:commonly used, high capacity, good rate capability,higher charging voltage,rapid loss of capacity; LiMn2O4:spinel structure, lower cost and safer than LiCoO2, lower capacity,easy phase changes; V2O5、LiV3O8:low voltages LiFePO4:olivine structure,two-phase(FePO4 and LiFePO4), relatively constant voltage,low electronic conduction; LiMnPO4、LiCoPO4:higher open circuit voltages(4.1v,4.8v), lower capacities; Li(Mn,Fe,Co)PO4、Li3V2(PO4)3:high operating voltage，good performance at high discharge currents; 3. Cathode performance Fig. 2. Plateau voltage and capacity (see Fig. 1) for LiFePO4 [123,153–162] and LiCoO2 [163–167] with a charging voltage of 4.2V and discharge current of 1C. Fig. 3. Plateau voltage and capacity for LiFePO4 [123,150,153,156,158–161,168–174] with a charging voltage of 4.2V and discharge current of 0.1C. The operating voltage for LiCoO2 is higher than that for LiFePO4 ，LiFePO4 has a narrower voltage range. A reduction in the discharge current increases the capacity of LiFePO4. Fig. 4. Plateau voltage and capacity for Li(Ni1/3Mn1/3Co1/3)O2 ,LiCoO2, LiFePO4 , and LiMn2O4 with a charging voltage of 4.3V and discharge current of 1C. Fig. 5. Plateau voltage and capacity (see Fig. 1) for Li(Ni1/3Mn1/3Co1/3)O2,LiMn2O4 and LiCoO2 with a charging voltage of 4.3V and discharge current of 0