A new advancement from MIT researchers has drastically improved the energy storage capacity of supercapacitors made from concrete, potentially paving the way for everyday infrastructure to double as massive energy storage systems writes Andrew Paul Laurent for MIT News. This innovative material, referred to as electron-conducting carbon concrete, is created by combining cement, water, and ultrafine nanoscale carbon black particles with an electrolyte to form a conductive “nanonetwork.” The recent optimization of electrolytes and manufacturing processes has increased the energy storage capacity of these carbon-cement supercapacitors by a factor of ten. This means that the amount of concrete needed to power an average home for a day has shrunk from approximately 45 cubic meters—the volume of a typical basement—to about five cubic meters, roughly the volume of a single basement wall.
The jump in energy density was achieved through a deeper nanoscale understanding of how the carbon-cement material functions. Using a high-resolution imaging technique called FIB-SEM tomography, researchers from the MIT Electron-Conducting Carbon-Cement-Based Materials Hub were able to reconstruct the conductive nanonetwork, discovering that it forms a fractal-like “web” around the concrete pores. This web allows electrolytes to infiltrate the material and facilitates the flow of electrical current through the system. Armed with this knowledge, the team experimented with different electrolytes and concentrations, finding that a wide range, including seawater for potential coastal applications, could be viable. The best performance was achieved using organic electrolytes, specifically those combining quaternary ammonium salts with acetonitrile, which allows one cubic meter of this carbon-cement version to store over 2 kilowatt-hours of energy.
The researchers also streamlined the manufacturing process by adding the electrolyte directly into the mixing water instead of soaking the cured electrodes. This change eliminated electrolyte penetration as a limitation, allowing the team to cast thicker, more energy-dense electrodes. The development of this material is part of a larger push toward multifunctional concrete, which integrates abilities like self-healing, carbon sequestration, and energy storage into the world’s most-used construction material. Lead author Admir Masic argues that taking advantage of concrete’s ubiquitous scale offers significant benefits for sustainability and energy solutions. While conventional batteries maintain a higher energy density, this carbon-cement material can be incorporated directly into architectural elements and last for the lifetime of the structure itself.
The potential for this concrete goes beyond simple storage. Taking inspiration from Roman architecture, the team built a miniature arch prototype that not only supported a load and powered an LED light but also exhibited a unique self-monitoring capacity. The light flickered as the load increased, suggesting that the stress impacts the electrical contacts or charge distribution. Researchers envision using this phenomenon to monitor a large-scale structure’s health in real-time, detecting stressors like high winds. Ultimately, the team believes this carbon-cement supercapacitor is a viable substitute for traditional batteries in many applications, helping to solve the critical energy storage gap needed for the renewable energy transition and enabling future developments like roads that charge electric vehicles.
Read more here: https://news.mit.edu/2025/concrete-battery-now-packs-ten-times-power-1001