Chloride-Ion Batteries: Evolution of Electrolyte Systems and the Promise of Polymer-Based Conductors

The development of solid-state electrolytes represents a significant research focus in energy density, promising substantial improvements in safety and performance. This approach is particularly advantageous for chloride-ion batteries (CIBs), where the dissolution of electrode materials in conventional liquid electrolytes constitutes a persistent and critical challenge. In this regard, a gel polymer electrolyte (GPE) with its liquid components immobilized and stabilized by a solid matrix, capable of retaining almost all the advantageous natures of the liquid electrolytes and circumventing the interfacial issues that exist in the all-solid-state electrolytes, is of great significance to realize rechargeable batteries with an extended working temperature range. In this paper, we focus on developing a gel polymer electrolyte for a chloride-ion battery using ethylene carbonate (EC) and propylene carbonate (PC) plastcizers. The suitable ratio of EC and PC is determined based on the ionic conductivity and activation energy of the GPE membrane. The optimized GPE shows an activation energy of 0.22 eV and a conductivity of 8.99 × 10 -4 S cm -1 .