Concrete battery achieves tenfold storage capacity: Buildings as energy storage

Concrete is the most widely used building material in the world. In future, it could not only serve as an all-purpose building material, but also store energy like a battery. Researchers at the Massachusetts Institute of Technology (MIT) have further refined a "concrete battery", which stores electrical energy and is structurally resilient at the same time. The results have been published in the Proceedings of the National Academy of Sciences (PNAS).

How the concrete battery works

This type of battery consists of cement, water, ultrafine carbon black and electrolytes. This creates a conductive nanocarbon network in the concrete. Admir Masic, lead author of the study and co-director of the MIT EC³ Hub, explains:

Understanding how these materials ‘assemble’ themselves at the nanoscale is key to achieving these new functionalities.

This network allows electrolytes to penetrate the pores and promote current flow.

Increasing energy density

In experiments, optimized electrolytes enabled the energy storage capacity of concrete to be increased tenfold. In 2023, around 45 cubic meters of concrete were needed to meet a household's daily energy needs. Today, only around 5 cubic meters are sufficient, which is comparable to the volume of a basement wall.

Damian Stefaniuk, lead author of the study, explains:

A cubic meter of this version of ec3 — about the size of a refrigerator — can store over 2 kilowatt-hours of energy.

This is roughly equivalent to the electricity consumption of a refrigerator for one day.

Architecture and practical applications

Concrete batteries can be integrated directly into building elements such as walls, floors or domes. Inspired by Roman architecture, the researchers built a miniature arch that supported its own load while also powering an LED. Masic explains:

There may be a kind of self-monitoring capacity here.

Light intensity varies depending on the load, allowing conclusions to be drawn about structural integrity in real time.

Outlook

Concrete batteries offer potential for parking lots, roads and coastal infrastructure. As Stefaniuk explains:

With these higher energy densities and demonstrated value across a broader application space, we now have a powerful and flexible tool that can help us address a wide range of persistent energy challenges.

It combines load-bearing architecture with energy storage, opening up perspectives for a sustainable, multifunctional construction of the future.