Composite polymer electrolytes are developed towards nanosized fillers to improve electrochemical properties upon the decrease of the size of the filler grain. Further improvement can be achieved by means of chemical incorporation of the inorganic part into the polymeric backbone. By these means both branched and crosslinked structures can be achieved with strict control of crosslink density. The paper presented shows the possibilities of tailoring the properties of organic-inorganic composite towards its application in lithium batteries. The increase of conductivity has been proved together with the improvement of material homogeneity, lack of crystallization, improved thermal stability of the electrolyte and improved salt dissociation, efficient stabilization of lithium-CPE SEI and promising cycling properties. (C) 2013 Elsevier B.V. All rights reserved.