Researchers at Michigan Technological University are working on it. Actually, their design is a twist on what’s called an asymmetric capacitor, a new type of electrical storage device that’s half capacitor, half battery. It may be a marriage made in heaven.
Capacitors store an electrical charge physically and have important advantages: they are lightweight and can be recharged (and discharged) rapidly and almost indefinitely. Plus, they generate very little heat, an important issue for electronic devices. However, they can only make use of about half of their stored charge.
Batteries, on the other hand, store electrical energy chemically and can release it over longer periods at a steady voltage. And they can usually store more energy than a capacitor. But batteries are heavy and take time to charge up, and even the best can’t be recharged forever.
Enter asymmetric capacitors, which bring together the best of both worlds. On the capacitor side, energy is stored by electrolyte ions that are physically attracted to the charged surface of a carbon anode. Combined with a battery-style cathode, this design delivers nearly double the energy of a standard capacitor.
Now, Michigan Tech researchers have incorporated a novel material on the battery side to make an even better asymmetric capacitor.
Their cathode relies on nickel oxyhydroxide, the same material used in rechargeable nickel-cadmium or nickel-metal hydride batteries. “In most batteries that contain nickel oxyhydroxide, metallic nickel serves as a mechanical support and a current collector,” said chemistry professor Bahne Cornilsen, who had been studying nickel electrodes for a number of years, initially with NASA support. A few years ago, the Michigan Tech team had a chance to experiment with something different: carbon foam. He suggested replacing the nickel with carbon foam.
Carbon foam has advantages over nickel. “It’s lighter and cheaper, so we thought maybe we could use it as a scaffold, filling its holes with nickel oxyhydroxide,” said Tony Rogers, associate professor of chemical engineering.
Carbon foam has a lot of holes to fill. “The carbon foam we are using has 72 percent porosity,” Rogers said. “That means 72 percent of its volume is empty space, so there’s plenty of room for the nickel oxyhydroxide. The carbon foam could also be made of renewable biomass, and that’s attractive.”
But how many times can you recharge their novel asymmetric capacitor? Nobody knows; so far, they haven’t been able to wear it out. “We’ve achieved over 127,000 cycles,” Rogers said.
Other asymmetric capacitors have similar numbers, but none have the carbon-foam edge that could make them even more desirable to consumers.
“Being lighter would give it a real advantage in handheld power tools and consumer electronics,” said Rogers. Hybrid electric vehicles are another potential market, since an asymmetric capacitor can charge and discharge more rapidly than a normal battery, making it useful for regenerative braking.
The group has applied for a patent on their new technology. Their research was funded by funded by the US Department of Energy, the Michigan Universities Commercialization Initiative, the Michigan Tech Research Excellence Fund and the Michigan Space Grant Consortium.
Michigan Tech chemical engineering professor Michael Mullins is also a member of the research team. Graduate students contributing to the project are PhD graduate Matthew Chye and PhD student Wen Nee Yeo of the chemical engineering department and MS student Padmanaban Sasthan Kuttipillai and PhD student Jinjin Wang of the chemistry department.
Marcia Goodrich | Newswise Science News
A big nano boost for solar cells
18.01.2017 | Kyoto University and Osaka Gas effort doubles current efficiencies
Multiregional brain on a chip
16.01.2017 | Harvard John A. Paulson School of Engineering and Applied Sciences
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).
Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...
10.01.2017 | Event News
09.01.2017 | Event News
05.01.2017 | Event News
18.01.2017 | Power and Electrical Engineering
18.01.2017 | Materials Sciences
18.01.2017 | Life Sciences