The addition of optimumcetyl pyridiumchloride (CPC)modified montmorillonite (CM) increases the ionic conductivity of poly(acrylonitrile)-based electrolytes by roughly two orders of magnitude. Specific interactions between the silicate layer, the nitrile group, and the lithium cation were investigated by FTIR, solid-state NMR, dielectric analyzer, and alternating current impedance. IR and NMR spectra confirm that the negative charges in the silicate layers alter the ionic charge environment of the PAN-based electrolyte composites, which have the same function as the polar group in PAN. The optimum CM content to achieve the maximum ionic conductivity is 6 phr. However, untreated montmorillonite leads to insignificant polymer intercalation, the negative charges in the silicate layers fail to appreciably disturb the attractive force of the lithium salt, and the resulting conductivity improvement is also less than that of the CM additives.