Evaluation of ionic mobility and transference number in a polymeric solid electrolyte by isothermal transient ionic current method

We proposed a new method for evaluating mobilities of both Li+ and SCN− ions in a polymeric solid electrolyte formed by poly (ethylene succinate) and LiSCN. The method is based on the isothermal transient ionic current (ITIC) technique by using an ion‐blocking platinum electrode and an ion‐reversible lithium electrode. The differences of the ITIC profiles, depending on the kind of the electrodes, provided both mobilities of Li+ and SCN− ions, and their assignment. The mobilities of Li+ and SCN− ions at 90 °C were 1.3–4.2×10−6 cm2 V−1 s−1 and 5.3–10.7×10−8 cm2 V−1 s−1, respectively. The transference number of Li+ ions was 0.92–0.99.