Fragmented cement composite with an electrical pattern on top. PNAS
A combination of cement and charcoal powder might allow homes to store enough energy for a whole day in their concrete basements. Both buildings and wind turbines might benefit from this novel approach to making a supercapacitor, which is an alternative to batteries that can discharge energy considerably quicker. Concrete road bases might one day be used to wirelessly recharge electric vehicles as they drive along, provided that this technology is combined with renewable energy sources.
“The materials are available for everyone all over the place, all over the world,” says MIT’s Franz-Josef Ulm. Which implies we’re not limited in the same way that batteries are.
Ulm and his team demonstrated that when carbon black (a finer type of charcoal) is combined with cement and water, it forms a solid block with numerous branching, wire-like structures packed with the carbon. Soaking the concrete in a common electrolyte solution, such potassium chloride, causes the electrolyte’s charged particles to settle on the carbon-wire structures, providing energy storage capacity.
Then, by placing a thin insulating layer between two 1 cm wide by 1 mm thick slabs of the material, they created a supercapacitor. By linking together three of these supercapacitors, we were able to create a 3-volt battery powerful enough to power a tiny LED light.
The researchers suggest that making 12-volt supercapacitors that can be linked together is the next logical step in order to provide additional charging power for bigger devices. A concrete cube of 3.5 metres on each side was found to be capable of storing 10 kilowatt-hours of energy, according to their calculations. That is nearly a third of the average daily home electricity usage in the US and about 1.25 times the average in the UK.
In principle, the material could store energy for a solar-powered home for more than 27 years, even after being charged and discharged 10,000 times.
Yury Gogotsi from Drexel University in Pennsylvania notes that one engineering challenge is that conventional concrete slabs would need to be replaced with what amounts to “concrete plywood” built with the supercapacitors. He speculated that it would be difficult to maintain the supercapacitor moist with the conductive salt solution over the life of the structure or road.
The MIT group was still upbeat about how many individuals could try out their own variations on this straightforward plan for a cheap supercapacitor.
Professor of Materials Science and Engineering at MIT, Admir Masic, says, “The fundamental aspect of this technology is it’s two historical, ancient materials that come together, that we have known for millennia.”
FAQs
1. What is the concept behind energy-storing concrete for solar-powered homes?
Energy-storing concrete combines cement and charcoal powder, forming wire-like structures filled with carbon that act as a supercapacitor, enabling concrete basements to store energy for extended periods.
2. How does the supercapacitor in concrete work as an alternative to batteries?
Supercapacitors discharge energy much quicker than traditional batteries, making them a promising alternative for energy storage in buildings and renewable energy applications.
3. What are the potential applications of energy-storing concrete beyond solar-powered homes?
The technology could benefit wind turbines, concrete road bases for wireless electric vehicle charging, and other devices requiring energy storage.
4. How much energy can a concrete cube store with this technology?
According to calculations, a 3.5-meter concrete cube could store 10 kilowatt-hours of energy, equivalent to a significant portion of average daily home electricity usage.
5. How long can the material store energy, and how many cycles of charging and discharging can it endure?
The material can theoretically store energy for more than 27 years and endure 10,000 charging and discharging cycles.
