New cement technology could turn buildings into batteries

Researchers from Chalmers University of Technology in Sweden have developed a concept for a rechargeable cement-based battery. One day the technology could turn an entire building into a massive energy storage device akin to a giant battery. The technology has some interesting possibilities as cement is one of the most commonly used building materials in the entire world.The concept involves a cement-based mixture with small amounts of short carbon fibers added to increase the conductivity and flexural toughness of the material. Also embedded inside the cement mixture is a metal-coated carbon-fiber mesh with iron for the anode and nickel for the cathode. Other research has investigated concrete batteries in the past, but they had very low performance.

Researchers at Chalmers had to come up with a new way to produce the electrode. The idea they came up with created a rechargeable system using an idea that hadn't been explored. The cement-based battery has an average energy density of seven watthours per square meter, which is about ten times better than previous concrete batteries can produce.

The researchers point out the energy density is still very low in comparison to commercial batteries. Still, they believe that limitation can be overcome thanks to the huge volume the battery would offer when used to produce buildings. The benefits of having a huge multistory building that is essentially a massive battery are apparent, including things like powering lighting inside the building, providing cellular connectivity in remote areas, or any of many other power needs.

Scientists working on the project are clear that the idea is at a very early stage. There are numerous major questions remaining that must be solved before the cement battery could become a reality, with one of the main challenges being extending the service life for the battery and developing recycling techniques.