4-PROBE POLARIZATION TECHNIQUES AND THE APPLICATION TO INVESTIGATIONSOF SOLID-STATE ELECTROCHEMICAL DEVICES

The application of sequential, bipolar, square-wave, current pulses to a solid-state electrochemical device with two properly positioned ref erence electrodes, has greatly facilitated the characterization of cel l performance. This technique is particularly useful in identifying th e rate-limiting step by separation of polarization distributions among cell components. Additional utility of this technique includes fast r esults and easy data interpretation. In fact, the current pulse sequen ces can be superimposed on a cell under normal operation to determine the kinetic and transport properties of the electrolyte and electrode materials in situ during cell operation.