Boring old bricks might not seem like something that can really be made high-tech, but researchers keep proving us wrong. Now, a team has found a way to turn bricks into energy storage devices, using them to power a green LED in a proof of concept study. A brick wall doesn’t exactly do much – sure it holds up the roof and keeps the cold out, but maybe the bricks could pull their weight a bit more. That was the goal for a team of scientists at Washington University in St Louis, who wanted to test whether bricks could be used to store electricity. The team started with regular red bricks, then gave them extra abilities by coating them in a conductive polymer called PEDOT. This stuff is made up of nanofibers that work their way inside the porous structure of the bricks, eventually turning the whole into “an ion sponge” that conducts and stores energy. In particular, these bricks become supercapacitors, which can store larger amounts of energy and be charged and discharged more quickly than batteries. They can be stacked together to make a bigger or smaller energy storage device, and the whole wall is then finished off with a coat of epoxy to keep the elements out and the electricity in. In tests, the team showed that a brick could charge to 3 volts in 10 seconds, and then light up a green LED for 10 minutes. It even worked underwater. Scaling it up, the team says that these power bricks could be hooked up to renewable sources like solar cells, to run an array of microelectronic sensors and lights. And as a supercapacitor, the bricks could be recharged hundreds of thousands of times every hour. “PEDOT-coated bricks are ideal building blocks that can provide power to emergency lighting,” says Julio D’Arcy, lead author of the study. “We envision that this could be a reality when you connect our bricks with solar cells – this could take 50 bricks in close proximity to the load. These 50 bricks would enable powering emergency lighting for five hours.” The method is reportedly simple and inexpensive to perform, and can be done on brand new bricks or to recycle old ones. The research was published in the journal Nature Communications.