All-Solid-State Chloride-Ion Battery with Inorganic Solid Electrolyte

Chloride-ion batteries have some attractive properties such as high energy density and low cost. However, they have poor cycle performance because chloride as an active material tends to dissolve into a polar solvent. Herein, an all-solid-state chloride-ion battery is demonstrated with KCl-doped PbCl2 as a solid electrolyte to suppress the dissolution of chloride. The all-solid-state cell with BiCl3 as the cathode had an initial discharge capacity of 187 mAh g(-1), which corresponds to 73 % of the theoretical capacity of BiCl3. Moreover, it exhibited better cyclability compared to the previously reported non-aqueous cell with BiCl3 cathode. During the charge-discharge process, XRD and XPS analysis confirmed the unique behavior of conversion reaction by Cl- anion, where Bi is produced by discharging and BiCl3 returns by charging.