SBIR Phase II: High-Power and High-Energy-Density Enzymatic Fuel Cell through an In Vitro Synthetic Enzymatic Pathway

This Small Business Innovation Research Phase II project seeks the further development of metal-free enzymatic fuel cells (EFCs) that can completely oxidize sugar (maltodextrin) to yield electricity. Sugar-powered EFCs have received increasing interest as next-generation, environmentally friendly bio-batteries. These bio-batteries, which will be fully biodegradable, non toxic, and easily refillable, are envisioned as next-generation green power sources, particularly for portable electronic devices (e.g., smartphones, portable computers, tablets, and GPS systems to name a few). These Sugar-powered EFCs with a feed of 20% maltodextrin utilizing a proprietary synthetic cocktail of enzyme catalysts for sugar oxidation, have an energy storage density of approximately 800 Ah/kg, nearly 20-times that of lithium batteries. The technical objectives of this project are the following: (i) to further increase their power density to 10 mW/cm2, (ii) to prolong their lifetimes to months, and (iii) to develop a commercial cost competitive product. The use of a low-cost chemical ingredient along with the use of engineered redox enzymes in sugar biobatteries, could increase their power output, prolong their lifetime, and decrease their production cost. In this SBIR II project, Cell Free Bioinnovations Inc. will make prototype high energy density power banks that could charge smartphones directly by integrating synthetic biology, protein engineering, nanobiotechnology, and electrochemistry. The broader impact/commercial potential of this project is the demonstration of the prototype bio-inspired sugar-powered biobatteries featuring high-energy storage density (e.g., 800 Ah electricity/kg of 20% sugar solution, nearly twenty times that of lithium ion batteries), fast refilling by the addition of a sugar solution, non toxic and safe to handle and use. Because sugar-powered EFCs are based on low-cost biocatalysts and do not require costly or rare metals, they are disposable and biodegradable devices. High-energy storage density EFCs would have broad potential applications as rechargeable battery chargers (e.g., cellular phone chargers for outdoor use or for portable military devices), educational toy kits, and disposable (primary) batteries. In the future, sugar-powered EFCs could potentially replace some secondary (rechargeable) batteries and primary batteries. In addition, the innovation of EFCs equipped with this cell-free synthetic pathway would greatly promote the concept of cell-free biomanufacturing composed of synthetic enzymatic pathways.