With so much excess carbon dioxide in the atmosphere, researchers from every corner of the globe are working on innovative ways to soak it up. Penn State University scientists have gone a step further with a powerful new battery that not only soaks up CO2, but also repurposes it to make more energy. Their pH-gradient flow cell battery is not the first of its kind, but it is the most powerful – take a closer look after the jump.
In an article published by Environmental Science and Technology Letters, the Penn State researchers note the discrepancy between CO2 concentrations in regular air and exhaust gases created by fossil fuel combustion results in an “untapped energy source for producing electricity.”
“One method of capturing this energy is dissolving CO2 gas into water and then converting the produced chemical potential energy into electrical power using an electrochemical system,” they write.
While previous attempts to convert CO2 into electricity have been successful, the researchers say power densities were limited, and ion-exchange technology expensive. They said their ph-gradient flow cell battery is considerably more powerful.
“In this approach, two identical supercapacitive manganese oxide electrodes were separated by a nonselective membrane and exposed to
an aqueous buffer solution sparged with either CO2 gas or air,” they write. “This pH-gradient flow cell produced an average power density of 0.82 W/m2, which was nearly 200 times higher than values reported using previous approaches.”
Engadget breaks this down for lay readers: “As ions are exchanged between the denser CO2 solution and normal air solution, the voltage changes at the manganese oxide electrodes in either tank. This stimulates the flow of electrons between the two connected electrodes and voilà: electricity.”
They also report that the process can essentially be reversed to recharge the battery, and that Penn State was able to repeat this process 50 times without losing performance.
For now, the researchers aren’t ready to scale their technology, but when they do, they envision it embedded in power plants, diverting atmospheric CO2, and slowly chipping away at one of the most epic challenges humans have ever faced: climate change.
Images via Environmental Science and Technology Letters, Pexels