Bio-sourced Black Soldier Fly (Hermetia illucens) Maggot Chitosan/PVA/PAN-based Polymer Electrolyte Membrane for Sustainable Energy Storage Applications

The global energy crisis sparked by dwindling fossil fuel reserves has precipitated efforts to develop sustainable battery technologies, as conventional dry cell batteries utilize toxic lead, graphite, and manganese oxide components that pollute the environment. Chitosan derived from black soldier fly (Hermetia illucens) maggot presents a biodegradable substitute. This study fabricated chitosan-based polymer electrolyte membranes by blending chitosan with polyvinyl alcohol (PVA) and polyacrylonitrile (PAN), then doping with ammonium chloride (NH4Cl) using the solvent-casting method. Varying NH4Cl compositions aimed to maximize ionic conductivity. Chitosan (13.455% water, 27.810% ash) was subsequently combined with PVA/PAN (20:80 w/w), NH4Cl, and casted onto petri dishes. Electrolyte membranes exhibited a maximum conductivity of 0.19612 ± 0.01572 S/cm with 0.9 g NH4Cl. FTIR spectroscopy verified the incorporation of chitosan (peaks at 3446.79 cm–1, 1643.35 cm–1, and 1151.50 cm–1), PVA (3446.79 cm–1 and 1136.07 cm–1), and NH4Cl (3371.57 cm–1 and 721.38 cm–1). SEM imaging visualized the incorporation of NH4Cl within the membrane. The chitosan-based biodegradable approach is compelling but limited by 0.19612 S/cm ionic conductivity, necessitating further compositional and processing optimizations for viable applications. Though it is promising for sustainable bio-sourced energy storage, challenges remain in enhancing conductivity through advanced polymer blends/dopants and scaling up for commercial biobattery manufacturing.