| This dissertation includes four parts.Part one: Some backgrounds about this dissertation are giving in this part. The recent situation and advances in the studies on the lithium ion mineral fast ion conductors and the electrode materials particularly the cathode materials for the lithium ion battery are reviewed.Part two: This part deals with the preparation and characterization of new perovskite-type lithium ion conductors. The three new lithium ion solid electrolyte systems of Li3xLa0.67-xMIIIyTi1-2yNbyO3, Li3XLa0.67-xMIIITi1-2yVyO3 and Li3xLa0.67-xMIIIyTi1-2yPyO3 (M=Sc3+, Y3+, Nd3+, Sm3+, Eu3+,Yb3, Cr3+, Fe3+, Al3+, In3+) were prepared by high temperature solid state reaction using M3+ and M5+ partly substituted Ti4+ in the perovskite parent. The compositions of above systems have been characterized by AC impedance, XRD, IR and DC polarizing measurements. The results show that the compositions doped with M3+ and M5+ have high conductivities with about 10-4s/cm at room temperature. The synthesis reaction temperatures of above three systems are lower than that of undoped perovskite parent. And the electrochemical stability for the compositions of above systems is getting much better. The decomposition voltages of the compositions that doped with M3+ and M5+ are higher than 1 .5V. The compositions doped with rare earth ion and Nb5+ are the most stable and their decomposition voltages are about 1 .8V-2.2V.The compositions which were prepared at 1290℃-1300℃ possess the highest conductivities. The preparing temperature for the compositions of Li3xLa0.67-xInyTi1-2yMvyO3 (Mv=Nb5+, V5+, P5+) system is about 1270℃ which is much lower than that of Li3xLa2/3-xTiO3 system (about 1350℃). The maximum conductivity is 5.81 × 10-4 S/cm at room temperature for the initial composition of x=0.10, y=0.050 in the Li3xLa0.67-xInyTii.2yNbyO3 system. The conductivities of other compositions are about 1.00×10-4-3.00× 10-4 S/cm. IR measurements indicate the compositions of the three systems are not so stable to CO2 and H2O in atmosphere.Part three: The preparation and characterization of mineral lithium fast ion conductors, which are based on LiTia(PO4)3, have been prepared by conventional solid state reaction using refined natural kaolinite as a starting material. Three minerallithium fast ion conductor systems of Li1+2xAlxScyNbyTi2-x-2ySixP3-xO12 system (referred as to Sc-Nb-Lisicons), Li 1+2x+3yAlxScyZnyTi2-x-2ySixP3-xO 12 system (referred as to Sc-Zn-Lisicons), Li1+2x+yAlxScy(Ti, Sn)1-x/2-y/2SixP3-xO12 system (referred as to Sc-Sn-Lisicons) were studied. For the Sc-Nb-Lisicons system, XRD results show that a R3c structure can be found in the composition range of x=0.1or x=0.2, y≤0.4 and x=0.3, y≤0.25. AC impedance measurements indicate that the initial compositions with x=0.1 , y=0.3 and x=0.2,y=0.15 possess higher conductivities in the system with 1.05×10-4S/cm and 2.78×10-4S/cm at room temperature, respectively and 8.00 × 10-3S/cm and 7.82× 10-3S/cm at 573K, respectively. Their activation energies are about 31.4kJ/mol and 34.8kJ/mol in the temperature range 423K-573K, respectively. For the Sc-Zn-Lisicons system, the initial composition with x=0.1, y=0.08 has the best ionic conductivity of 1 . 1 9× 1 0-4S/cm at room temperature, its activation energy is 30.6kJ/mol. While at 573K, the initial composition with x=0.1, y=0.18 possesses the maximum ionic conductivity of 2.08 × 10-2S/cm. X-ray diffraction analysis shows that a phase with space group R3c exists in the composition range of x=0. 1,0.2,y≤0.2. For the Sc-Sn-Lisicons system, the initial composition with x=0.3, y=0.1 hasmaximum ion conductivity of 4.50 × 10-5S/cm at room temperature and 4.56× 10-2 S/cm at 673K, its activation energy is 39.1kJ/mol in the temperature range of 423K-673K. X-ray diffraction analysis shows that a phase with space group R3c exists in the composition range of x≤0.3, y≤0.6. IR spectra analysis indicates that most compositions of the above three systems are not stable to H2O, but stable to CO2 in the air. Th...
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