Constant-phase element identification in conductivity sensors using a single square wave

This paper proposes a novel method to measure the electrical conductivity of solutions in the time domain by using a single square-wave current and two titanium electrodes. This method allows us to determine both the conductivity (σ) of the solution and the two parameters of the constant-phase element (CPE) due to the electrodes. Experimental results show that the proposed method achieves conductivity measurement ranges close to those obtained with platinum probes or tetrapolar measurements, which are more expensive, and provides information about electrode condition.