Design Optimization of Saltwater Magnesium-Air Battery Using Activated Carbon Derived

Abstract

The advent of large-scale renewable energy generation is driving a growing need for new electrochemical energy storage systems. Metal-air batteries, having a promising technology that could address this need, faces challenges due to the costly and locally unavailable production of air-cathode. Thus, the proponents came up with the idea of designing portable metal-air battery with configured air-cathode layering technology using activated carbon derived from waste coffee grounds and saltwater as electrolyte. The design process involves genetic algorithm to optimize both performance and dimensions. In this study it has been proven that activated carbon derived from waste coffee grounds possess characteristics that is significant for the production of air-cathode and batteries such as microporosity and absorption property. The fabricated air-cathode improved conductivity, affordability, and promotes the passage of ambient air required for electrochemical reaction to occur. Result shows that genetic algorithm successfully optimized the dimension of the device making it portable yet with comparable performance. The device is capable of storing 285 mL of saltwater enough to power a radio for 4 hours, LED lightings for 11 hours and can fully charge mobile phones. The device has a rated output of DC 5-30V/ 2A / 10-60W, capacity of 60 Wh and optimized dimension of 130 mm x 80 mm x 172.25 mm.