Chitosan–lithium triflate electrolyte in secondary lithium cells

Films prepared from high molecular weight chitosan are shown to exhibit the highest electrical conductivity of 2.14×10−7 S cm−1. The electrical conductivity is further enhanced to 1.03×10−5 S cm−1 when ethylene carbonate (EC) is used as a plasticizer. X-ray diffraction (XRD) shows that EC disrupts the crystalline nature of chitosan acetate. Infrared (IR) spectroscopy reveals a shift in the amide band from 1590 to 1575 cm−1 on addition of LiCF3SO3. A film with a (chitosan+0.4 g EC) to LiCF3SO3 ratio of 80:20 gives the highest electrical conductivity of 3.0×10−4 S cm−1. This film is used as an electrolyte for the fabrication of chitosan-based secondary cells, viz., Li/chitosan–EC–LiCF3SO3/V2O5. The characteristics of the cells are presented in this paper.