Solid-state lithium ion electrolytes of lithium silicate based composites are provided which contain an anionic framework capable of conducting lithium ions. An activation energy for lithium ion migration in the solid state lithium ion electrolytes is 0.5 eV or less and room temperature conductivities are greater than 10−5 S/cm. Composites of specific formulae are provided and methods to alter the composite materials with inclusion of aliovalent ions shown. Lithium batteries containing the composite lithium ion electrolytes are also provided.