In this work lithium modified silica (Li-SiO2) nano-particles were synthesized and used as a single ion lithium conductor source in gel electrolytes. It was found that Li-SiO2 exhibited good compatibility with DMSO, DMA/EC (a mixture of NN-dimethyl acetamide and ethylene carbonate) and the ionic liquid, N-methyl-N-propyl pyrrolidinium bis(trifluoromethylsulfonyl) amide ([C(3)mpyr][NTf2]). Several get electrolytes based on Li-SiO2 were obtained. These gel electrolytes were investigated by DSC, solid state NMR, conductivity measurements and cyclic voltammetry. Conductivities as high as 10(-3) S/cm at room temperature were observed in these nano-particle gel electrolytes. The results of electrochemical tests showed that some of these materials were promising for using as lithium conductive electrolytes in electrochemical devices, with high lithium cycling efficiency evident. (c) 2007 Elsevier Ltd. All rights reserved.