Utilization of Methylene Blue and Banana Peels as RFB Components (Redox Flow Battery)

RFB (Redox Flow Battery) is a secondary battery that provides energy conversion between chemistry and electricity through an alternating redox reaction by 2 pairs of electrons and protons. RFB with active ingredient Vanadium (VRB) is a type of RFB that is widely used and has problems such as the price of Vanadium is expensive, is toxic and the solvent (H2SO4) is corrosive. Therefore, an inexpensive and environmentally friendly organic electrolyte component emerged, namely Methylene Blue and banana peels. Methylene Blue has 2 electron-proton pairs which provide a reversible redox reaction and have the potential as an active ingredient in the RFB electrolyte. Banana peels have potential as an electrolyte solvent because they contain carbohydrates, citric acid and mineral electrolytes (potassium, sodium salt, phosphorus and magnesium) which support the electrolyte properties of banana peels. The stages of making electrolytes by fermentation of banana peel solution, addition of Methylene Blue and testing (galvanostatic and stress). The test results showed that Methylene Blue was able to provide the best performance (efficiency) on RFB and banana peels as an electrolyte in the battery was able to produce a voltage exceeding the VRB output voltage.