Concrete battery turns walls into power banks with 10x energy boost

MIT researchers have developed a groundbreaking electron-conducting carbon concrete (ec3) that can store and release electricity, effectively turning building materials like walls, sidewalks, and bridges into large-scale energy storage systems. This new concrete battery offers a tenfold increase in energy density compared to earlier versions, reducing the volume needed to power a household from 45 cubic meters to about 5 cubic meters—roughly the size of a basement wall. The ec3 material integrates cement, water, ultra-fine carbon black, and electrolytes to form a conductive nanonetwork, enabling efficient energy storage and flow. Key innovations include mixing electrolytes directly into the concrete before casting, which creates thicker, more powerful electrodes, and the use of organic electrolytes that allow a cubic meter of ec3 to store over 2 kilowatt-hours—enough to power a refrigerator for a day. The material’s design was inspired by ancient Roman concrete techniques combined with modern nanoscience, and it has demonstrated multifunctional uses