NOVELTY - A single-ionic conductor comprising silicon dioxide lithium preparing method involves preparing mono-dispersed sphere-shaped functional type silicon dioxide by stirring a silicon source and aqueous ethanol solution in the presence of a catalyst under magnetic force by controlling reaction temperature to obtain uniform solution. The uniform solution is subjected to sol-gel or suspension filter or centrifugal separation to obtain a solid product, which is added with an oil-soluble azo containing free radical initiator and organic sodium salt solution to carry out free radical polymerization.    USE - Method for preparing single-ionic conductor with core-shell structure in polymer electrolyte.    ADVANTAGE - The method enables preparing single-ionic conductor with high lithium-ion transference number, better multiplying power and better cycle performance.    DETAILED DESCRIPTION - A single-ionic conductor comprising silicon dioxide lithium (SiO2Li+) preparing method involves preparing mono-dispersed sphere-shaped functional type silicon dioxide by stirring a silicon source and aqueous ethanol solution in the presence of a catalyst under magnetic force by controlling reaction temperature at 20-80 degrees C to obtain uniform solution. The uniform solution is subjected to sol-gel or suspension filter or centrifugal separation to obtain a solid product. The solid product is added with an oil-soluble azo containing free radical initiator and organic sodium salt solution to carry out free radical polymerization at 60-100 degrees C to obtain a free radical polymerization product. The free radical polymerization product is filtered or centrifuged to obtain a supernatant. The supernatant is dried under vacuum to prepare silicon dioxide-sodium (SiO2Na+) product, which is heated with lithium salt at 60-120 degrees C to carry out ion exchange. The heated product is dried under vacuum to obtain a finished product, where the catalyst comprises water, sodium hydroxide, sodium acetate and/or sodium oxalate.