Ionic transport and structural analysis of zinc chloride doped ί-carrageenan solid polymer electrolytes for energy storage devices

This study aims to develop a solid polymer electrolyte (SPE) with high ionic conductivity using ί-Carrageenan (iC) suitable for zinc-ion batteries. The SPEs are prepared through a straightforward solution-casting technique that employs ί-Carrageenan and zinc chloride, with deionized water as the solvent. Fourier-transform infrared (FTIR) spectroscopy is conducted to analyze the interactions between the polymer chains and ions, while X-ray diffraction (XRD) patterns are evaluated to determine crystallinity and confirm salt dissociation. Ionic conductivity is measured using impedance spectroscopy, achieving a maximum conductivity of ∼10 −4 S cm −1 . The contribution of cations to this conductivity is assessed using the Bruce-Vincent method, using a custom LabVIEW program on a sourcemeter and an LCR meter. A primary cell incorporating the SPE was fabricated and characterized to evaluate its feasibility, leading to the conclusion that, with some minor improvements, this SPE could serve effectively in zinc-ion batteries. • Developed ι-Carrageenan solid polymer electrolyte with high ionic conductivity. • Prepared SPEs via a simple solution-casting method using water as solvent. • FTIR and XRD analyzed polymer-ion interactions and crystallinity changes. • Achieved ionic conductivity of ∼10 −4 S cm −1 via impedance spectroscopy. • Fabricated primary cells shows SPE's potential for zinc-ion battery use.