This work reports the synthesis and characterisation of two new electrolytes based on polyethers (PEG and PPO) and polyphosphazene (PPz). In the structural study, the existence of new crystalline phases becomes apparent as a consequence of the co-ordination of the lithium salt (lithium triflate) and the ether group of the polymeric chain. The electrical and electrochemical study revealed good conductivity at 110 degrees C and excellent electrochemical stability and cyclability of the synthesised samples.