We can’t live without batteries, but sometimes it’s almost as if we can’t live with them. You know that feeling if your cell phone has ever desperately needed charging in a place where there wasn’t a plug in sight. But wait. What if your body was the battery?
If you try to imagine the human body acting as its own battery, you might come up with something like that spectacle of a suit covered with flashing lights in The Electric Horseman. That isn’t exactly where this is going. For now, your body isn’t about to charge your dying phone, either. What it can do is use a futuristic new fuel cell that can keep medical implants powered by taking the glucose you consume every day and converting it into electricity.
This new fuel cell may be tiny, and appears almost indistinguishable from a computer chip, but it generates an amazing amount of power that could turn you into something of a moving battery. It was designed by engineers at MIT and Technical University of Munich who wanted a solution for delivering a constant stream of power to next-gen devices that are implanted to treat certain medical conditions. Researcher Philipp Simons of MIT led a study recently published in Advanced Materials.
"By designing this entirely new device, we also needed to invent all the characterization apparatus required to test it out in the lab," Simons told SYFY WIRE. "We built a custom experimentation setup that allowed us to measure up to 30 fuel cells in rapid sequence and under well-controlled conditions."
While fuel cells are nothing new, this one is revolutionary because it is the smallest and most powerful glucose fuel cell ever. The silicon chip has all the power of a battery with none of the bulk. For anyone who needs an assist from something like a sensor, or a drug-delivery system that dispenses medicine at just the right time, it’s groundbreaking.
Like a battery, the fuel cell has two electrodes, an anode and a cathode, with an electrolyte in the middle (which is what allows electricity to be transmitted from the cathode to the anode. The anode (made of platinum) comes into contact with a glucose solution while water is in contact with the cathode. There are two electrons and two protons released when glucose is morphed into electricity. These are separated by the electrolyte. Electrons head to a circuit on the outside of the device to give it a jolt of electricity. Protons are conducted, and the only byproduct of the process is water.
Simons and his team were able to prove that the design worked when they were able to get voltage and current out of it.
"The anode is made up of porous platinum, which serves as both the catalyst of the reaction of glucose to gluconic acid, and as the current collector of the power source," he said. "The reaction of glucose to gluconic acid releases protons and electrons."
You might not believe what this gadget’s electrolyte is made of. It’s ceramic, though not just any ordinary ceramic, but ceria, a dense ceramic nanomaterial. Simons' team improved on previous fuel cells by deciding to go with a ceramic instead of a polymer. Unlike polymers, ceria can hold on to its electrochemical properties and won’t degrade, even at scorching temperatures. The only other types of materials used on the chip were metals.This will allow it to remain stable in the form of this extremely thin fuel cell, so it can possibly be morphed into ultrathin coatings for medical implants (which will also be powered by glucose) in the future.
Such a device could really become a thing as electroceuticals — therapeutic devices that zap neural impulses to organs — and other medical implants fast-forward medicine into the future. Neural impulses are electrical signals (yes, your body does produce some electricity on its own) that are transmitted across a nerve when that nerve is affected by an outside stimulus. The fuel cell is only as thick as one hundredth of a human hair, but so resilient it can survive temperatures up to about 1,110 degrees Fahrenheit. The reason this matters is because it will be able to withstand the extremely high temperatures of mandatory implant sterilization.
The MIT and Technical University team’s implant is a huge improvement on an actual battery that would otherwise eat up 90 percent of an implant’s volume. It also does away with the size limit batteries would require, since they need enough space to store energy. However, would it be possible to use a device like this to power your cell phone someday, with only glucose for fuel? Simons thinks so.
"While our vision is that the main benefits of our invention are most useful in implantable applications, the technology could also be used as the platform for biomass-powered external fuel cells," he said. "This would definitely be an exciting way to use this technology as well."
Maybe, in the best possible way, we are turning ourselves into cyborgs.