The effect of type of the inorganic filler and dopant salt concentration on the PEO–LiClO4 based composite electrolyte–lithium electrode interfacial resistivity

In the present paper the effect of the type of inorganic filler on the composite polymeric electrolyte–lithium electrode interfacial behavior is analyzed. Studies are performed in the wide LiClO4 concentration range using poly(ethylene oxide)dimethyl ether (PEODME) as an electrolyte matrix. It is demonstrated that both the formation and the growth of the resistive layers at the polymer electrolyte–lithium electrode interface are determined by the salt concentration range and depend also on the type of the filler used. It is demonstrated that for salt concentrations lower than 10−3 mol kg−1 or higher than 1 mol kg−1 addition of filler results in the suppression of the growth of the resistance of the interfacial layer. This effect has been related to an increase in lithium cation transference number observed in these salt concentration ranges in composite electrolytes compared to the pure PEODME–LiClO4 analogues. The effect of the filler on conductivity, microstructure and thermal characteristic of electrolytes studied is also discussed.