| Ionic conductors have extensive and valuable use in the energy and material fields. The research of the new and high conductivity material of lithium ionic conductor is always an interesting issue in the material field due to its low potential, light weight and providing high cell voltage and energy density.In this work, the solid solution of Li3.4Sio.4Vo.6O4 as the matrix was chosen because of its suitable path for the mobility of Li ions and the different material as the second phase to synthesize a series of lithium ionic conductor composites by sol-gel method, which bases on the opinion of the composites having higher ionic conductivity, and to research the synthetics method, compound-structure-function and so on. The following is the primary results:1. The research system and method were established through analyses and summing-up of documents of this field. The basic results include three aspects:The interests of lithium ionic conductors focused on the simple compounds, solid solution (substitution by aliovalent and isovalent) and the small composites which mostly are Al2O3 as the second phase and somesimple compounds as the matrix. The questions the researcher concerned are which system will be chosen and how to obtain the good lithium ionic conductor materials, which is the basic departure of the paper.The addition of second phase in composite can change the interface structure and the conduction mechanism, improve the matrix conductivity and other function such as the sintering, crisping and so on, so the research of composites are an interesting field of the ionic conductors.The synthesis of lithium ionic conductor is often by solid state reaction, but this method needs high temperature and leads to the volatility of lithium which not only causes the drift of the compounds but gets the no well-distributed materials. The above shows that a new and suitable method for the multi-compound lithium ionic conductors should be found.2. The solid solution matrix of Li3.4Sio.4Vo.eO4 was synthesized by the better sol-gel method and the ultra-fine powder and density pellet were acquired. During the preparation process of the solid solution, a series of effect conditions were discussed such as pH value, Si/H2O, the content of ligant, the surface active agent, the aging temperature, the drying means, the drier gel calcine and their effects on the gel quality, the process of sol-gel, the granular of powder and the density of the pellets, from which the best reaction condition was found.3. A series of ultra-fine, homogeneous powders and density pellets were synthesized, Li3.4Si0.4V0.6O4 as the matrix and the lithium salt and other oxides as the second phase. The effects of the second phase of its state, type, and the addition content on the ionic conductivity were discussed.4. The sol-gel method was improved by the following aspects:Thecombing of the traditional method and the inorganic polymer gel, avoids the usage of the expensive organic salt. Citric acid, taking the place of HNO3, solutes the substance which does not solute in solution, and it acts as the ligand of metallic ionic and the hydrolysis catalyst of Si(OC2H5)4, which reduces the pollution caused by NO2 which forms at the decompose process of the hot treatment.By changing the means of calcine of the drier gel, choosing the suitable temperature to burn the gel, the high temperature calcine time is shorted, which solves the question of the long period calcine. So the preparation process of the matrix and composite was finished by using more lower temperature than the traditional solid state reaction and more shorter time than the traditional sol-gel process.5. The matrix and the gel, powder and pellets of composites are characterized by IR, DTA, XRD, SEM. The following is the results:At the transition process, existing the polymerization of Si(OC2H5)4 and citric slats. (2)The transition temperature of the drier gel to powder at 400-600.(3)The solid solution matrix of Li3.4Sio.4V0.6O4 has the structure of Li3VO3 (high temperat...
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