Concrete walls could store electricity like giant batteries

After water, concrete is the most-used material on Earth. And researchers at MIT just gave it an unexpected superpower: the ability to store and release electricity.

Imagine your basement wall doing double duty—supporting your house and powering it at the same time. That's what this new concrete formulation makes possible. About 5 cubic meters of the material (roughly the volume of a typical basement wall) can hold enough energy to meet the daily electricity needs of an average American household.

The breakthrough matters because buildings are energy hogs. They account for over a third of global energy use and 40% of carbon emissions. Much of that footprint comes from concrete itself—making cement requires intense heat and chemical reactions that release CO2. If walls could store energy directly from solar panels instead of relying on separate batteries (which depend on scarce, environmentally costly materials to mine), the math changes.

How they did it

MIT researchers combined cement and water with ultra-fine carbon black particles and specially formulated electrolytes. The key innovation was switching the electrolyte—they found that organic electrolytes made from ammonium salts and acetonitrile performed 10 times better than previous attempts. They also changed the manufacturing process, mixing electrolytes into the water used to make concrete rather than soaking finished concrete in liquid. This created thicker, more powerful electrodes.

The result: one cubic meter of this concrete (about the size of a refrigerator) can store over 2 kilowatt-hours of energy—enough to power an actual refrigerator for a day.

This isn't the first attempt at energy-storing concrete. Researchers have previously filled bricks with conductive materials and added carbon fibers to concrete blocks. But the MIT team's 10-fold improvement in energy density represents a meaningful step toward practical application.

"What excites us most is that we've taken a material as ancient as concrete and shown that it can do something entirely new," said James Weaver, one of the researchers. "By combining modern nanoscience with an ancient building block of civilization, we're opening a door to infrastructure that doesn't just support our lives, it powers them."

The research was published in the Proceedings of the National Academy of Sciences in 2025. The next phase will be testing whether this concrete maintains its electrical properties over time and whether it can be manufactured at scale without dramatically raising costs. If it works, your future home's foundation might be doing more than holding up the walls.