Abstract: The invention relates to high-ionic conductivity electrolyte compositions. The invention particularly relates to high-ionic conductivity electrolyte compositions of semi-interpenetrating polymer networks and their nanocomposites as quasi-solid/solid electrolyte matrix for energy generation, storage and delivery devices, in particular for hybrid solar cells, rechargeable batteries, capacitors, electrochemical systems and flexible devices. The binary or ternary component semi-interpenetrating polymer network electrolyte composition comprises: a) a polymer network with polyether backbone (component I); b) a low molecular weight linear, branched, hyper-branched polymer or any binary combination of such polymers with preferably non-reactive end groups (component-ll and/or component-Ill, for formation of ternary semi-IPN system); c) an electrolyte salt and/or a redox pair, and optionally d) a bare or surface modified nanostructured material to form a nanocomposite.