Solid electrolyte system compared to a liquid electrolyte is desirable for some electrochemical applications. Natural polymers like polysaccharides were explored as polymer matrix in the development of solid electrolyte system. Among the polysaccharides screened, k- carrageenan showed promising results. Cyclic voltammetry of the I3 -/I- redox couple in k- carrageenan gel showed improved performance compared to aqueous medium. Composite films of k-carrageenan with KI and I2 as triiodide sources and polymer electrolytes based on k- carrageenan and ionic liquid, 1,3-dimethyl imidazolium iodide (DMII) with I2 were prepared and characterized.