A Virginia Tech research team has developed a battery that runs on sugar and has an unmatched energy density, a development that could replace conventional batteries with ones that are cheaper, refillable, and biodegradable.
While other sugar batteries have been developed, Zhang said his has an energy density an order of magnitude higher than others, allowing it to run longer before needing to be refueled.
In as soon as three years, Zhang’s new battery could be running some of the cell phones, tablets, video games, and the myriad other electronic gadgets that require power in our energy-hungry world, Zhang said.
“Sugar is a perfect energy storage compound in nature,” Zhang said. “So it’s only logical that we try to harness this natural power in an environmentally friendly way to produce a battery.”
This is one of Zhang’s many successes in the last year that utilize a series of enzymes mixed together in combinations not found in nature. He has published articles on creating edible starch from non-food plants and developed a new way to extract hydrogen in an economical and environmentally friendly way that can be used to power vehicles.
In this newest development, Zhang and his colleagues constructed a non-natural synthetic enzymatic pathway that strips all charge potentials from the sugar to generate electricity in an enzymatic fuel cell. Then, low-cost biocatalyst enzymes are used as catalysts instead of costly platinum, which is typically used in conventional batteries.
Like all fuel cells, the sugar battery combines fuel — in this case, maltodextrin, a polysaccharide made from partial hydrolysis of starch — with air to generate electricity and water as the main byproducts.
“We are releasing all electron charges stored in the sugar solution slowly step-by-step by using an enzyme cascade,” Zhang said.
Different from hydrogen fuel cells and direct methanol fuel cells, the fuel sugar solution is neither explosive nor flammable and has a higher energy storage density. The enzymes and fuels used to build the device are biodegradable.
The battery is also refillable and sugar can be added to it much like filling a printer cartridge with ink.
High-energy-density, green, safe batteries are highly desirable for meeting the rapidly growing needs of portable electronics. The incomplete oxidation of sugars mediated by one or a few enzymes in enzymatic fuel cells suffers from low energy densities and slow reaction rates. Here we show that nearly 24 electrons per glucose unit of maltodextrin can be produced through a synthetic catabolic pathway that comprises 13 enzymes in an air-breathing enzymatic fuel cell. This enzymatic fuel cell is based on non-immobilized enzymes that exhibit a maximum power output of 0.8 mW cm−2 and a maximum current density of 6 mA cm−2, which are far higher than the values for systems based on immobilized enzymes. Enzymatic fuel cells containing a 15% (wt/v) maltodextrin solution have an energy-storage density of 596 Ah kg−1, which is one order of magnitude higher than that of lithium-ion batteries. Sugar-powered biobatteries could serve as next-generation green power sources, particularly for portable electronics.
Comparison of energy densities among batteries and EFCs.
Brian Wang is a Futurist Thought Leader and a popular Science blogger with 1 million readers per month. His blog Nextbigfuture.com is ranked #1 Science News Blog. It covers many disruptive technology and trends including Space, Robotics, Artificial Intelligence, Medicine, Anti-aging Biotechnology, and Nanotechnology.
Known for identifying cutting edge technologies, he is currently a Co-Founder of a startup and fundraiser for high potential early-stage companies. He is the Head of Research for Allocations for deep technology investments and an Angel Investor at Space Angels.
A frequent speaker at corporations, he has been a TEDx speaker, a Singularity University speaker and guest at numerous interviews for radio and podcasts. He is open to public speaking and advising engagements.