Garnet-type Li₇La₃Zr₂O₁₂ (LLZO) is an attractive solid electrolyte material for lithium ion batteries. LLZO has good chemical stability and high ionic conductivity, but it is also rigid and brittle, which may result in poor contact with electrodes and mechanical failure. Composite electrolytes, which combine the advantages of both LLZO and solid polymer electrolyte, are promising solid electrolytes with high ionic conductivity, good chemical stability and mechanical properties. In this work, LLZO based composite electrolytes have been prepared and evaluated with materials characterization techniques and impedance spectroscopy.