Inductive effects and A.C. measurements with solid electrolyte cells

Abstract

Apparently negative permittivities have been measured for β-alumina solid electrolytes above room temperature but these were shown to be caused by the presence of a lead inductance. The change from positive permittivities at low frequencies (<1.4 MHz) to negative permittivities at higher frequencies depended on resonance in the series L-C-R circuit, with L as the lead inductance, and C and R as the series capacitance and resistance of the cell, respectively. It is argued that care must be taken before interpreting similar inductive effects in “fast-ion” conductors in terms of electrolyte phenomena. Circuit simulations are used to show that inductive effects are however not a complication with electrolytes of low conductivity (<10 −6 Ω −1 cm −1) and hence do not interfere with various kinds of complex plane analysis.