Crystalline Li3Po4/Li4SiO4 solid solutions as an electrolyte for film batteries using sputtered cathode layers

Crystalline solid solutions of 1:1 Li3PO4/Li4SiO4 were synthesized and tested electrochemically using thin film physical vapor deposited electrodes. After cathode deposition, the electrolyte/cathode structures were annealed at 700 °C for 2 h—a process that resulted in cathode crystallization without encouraging deleterious interfacial reactions. Results indicate that the electrolyte functioned well in this configuration. Test cells were taken through multiple charge/discharge cycles at different rates and temperatures and demonstrated a marked enhancement in performance parameters in comparison to previous reports. It is suggested that this material could function well in Li batteries fabricated using proper form factors.