Cement and electrode mixture key to capturing energy in concrete structures
Researchers in Switzerland have created a rechargeable cement battery, a potentially significant advancement in sustainable infrastructure, according to a recent article published in the journal Buildings.
The battery is a mixture of cement, carbon fiber and electrodes, and could effectively turn buildings into self-sufficient energy capturers, similar to solar panels.
“We are convinced this concept makes for a great contribution to allowing future building materials to have additional functions such as renewable energy sources,” said Luping Tang, a professor at the Department of Architecture and Civil Engineering at Chalmers University of Technology.
Being able to harness energy with concrete is a significant step toward sustainable infrastructure, as buildings currently use over a third of all the world’s energy and account for 40% of carbon emissions.
“Concrete … is the world’s most commonly used building material. From a sustainability perspective, it is far from ideal, but the potential to add functionality to it could offer a new dimension,” said Emma Zhang, a researcher in the department of architecture and civil engineering at Chalmers University of Technology.
The cement batteries would capture energy from the sun and store it in a structure’s walls and roof, using the energy to power lights and other sources during the evening.
The batteries could also be used to power LEDs, provide 4G in remote areas with low connectivity, offer cathodic protection against corrosion in concrete, and work as self-sufficient infrastructure monitoring systems.
“The concept of using structures and buildings in this way could be revolutionary, because it would offer an alternative solution to the energy crisis, by providing a large volume of energy storage,” Zhang said.
The batteries are created by combining a cement mixture with carbon fiber that makes them conductive, and with electrodes comprised of metal-coated carbon fiber mesh with iron and nickel-coated mesh.
At an average energy density of 7 Watthours per square meter, the batteries’ capacity is lower than commercials batteries, but has researchers estimating it could be capable of performing around 10 times better than earlier concrete batteries.
“We have a vision that in the future this technology could allow for whole sections of multi-story buildings made of functional concrete,” Zhang said. “Considering that any concrete surface could have a layer of this electrode embedded, we are talking about enormous volumes of functional concrete.”
Barriers remain, such as how to go up about upgrading the technology once it inevitably advances.
“Since concrete infrastructure is usually built to last 50 or even 100 years, the batteries would need to be refined to match this, or to be easier to exchange and recycle when their service life is over,” Zhang said.