Sodium cations solvated by polyethylene oxide have been confined by intercalation in the interlamellar space of an insulating layered solid, CdPS3. The frequency-dependent conductivity and the associated conductivity relaxation in the intercalated polymer electrolyte have been investigated. The temperature-dependent conductivity displays a distinct change in behavior at T similar to 225 K. Below 225 K the dc conductivity, sigma(dc), shows an Arrhenius temperature dependence, while for T > 225 K sigma(dc) rises sharply and follows the Vogel-Tamann-Fulcher relation, characteristic of ionic motion coupled to polymer relaxation modes. An analysis of the frequency-dependent conductivity using the electrical modulus representation showed that the electrical conductivity relaxation may be described in terms of the stretched exponential correlation function in the time domain, phi(t) = exp(-t/tau(sigma))(beta). The absence of any anionic contribution to the electrical response makes these intercalated polymer electrolyte systems attractive for fundamental studies on ionic motion in disordered polymeric media.