The conductivity of Mgl(2)-poly(ethylene oxide) mixtures can be increased if adducts of Mgl(2) and diethyl ether are used in place of pure Mgl(2). These materials show conductivities in the range of 10(-5) to 10(-6) S cm(-1) at 40 degrees C. The dependence of the conductivity on temperature and composition of the system was investigated.