Study of the Relaxational Polarization Dynamics of the LiPON Solid Electrolyte

The results of investigation of the polarization relaxation mechanism for the LiPON solid electrolyte by a discharge through an external load are presented. Test cells implemented in the form of encapsulated multilayer structures and previously studied by the standard techniques are tested on a special bench measuring discharge characteristics. The core of the method lies in charging the test cell from a stable voltage source up to saturation with the subsequent rapid switch to precision resistance and detection of the voltage drop. The measurements are taken in the load range from 0.1 MΩ to 10 Ω in the temperature range of –50 to 25°C. An equivalent electric circuit for the test cell is proposed, for which a mathematical model of the discharge process is constructed. In the context of the proposed model, the features of the experimental curves are explained by the processes of redox reactions of the lithium ions at the surface of the electrodes and generation of nonequilibrium charge carriers in the bulk upon the charging and discharging of the test cell.