Synthesis of chitosan-LiOH polymer electrolyte membrane with addition of sodium tripolyphosphate

摘要

The rapid advancement of technology leads to an increase in battery demand, one of which is lithium ion batteries. Lithium batteries have flammable liquid electrolytes when electrolyte leaks, and lithium metals in the battery will react wit h water, producing explosive hydrogen gas. Currently electrolytic solids as battery electrolytes have been widely developed. Chitosan is one type of natural polymer that has the potential as a solid electrolyte material. The addition of a cation with a low atomic mass such as lithium ions (Li~+) inside the polymer membrane enables an efficient charge transfer process. This study is an experimental study aimed at synthesizing a chitosan-based solid electrolyte membrane. The chitosan sample used is chitosan which has deacetylation degree of 98%. The chitosan-LiOH electrolyte membrane was synthesized using blending method with the ratio of chitosan-LiOH concentration of (100: 0), (95: 5), (90:10), (85:15), and (84:16) % w/w. The membrane obtained was characterized by color and thickness, determination of conductivity using LCR meter, and degree of crystallinity analysis with X-Ray Diffraction (XRD) tool. From the result of the research, clear yellow chitosan-LiOH membrane was obtained with an average thickness of 0.1 mm, with the highest conductivity obtained with the ratio of chitosan-LiOH concentration of (85:15) % w/w. Addition of sodium tripolyphosphate did not increase the conductivity of electrolyte polymer membrane due to the higher degree of crystallinity.