By combining cement, water, and carbon black, MIT researchers have created a unique, energy-storing substance. The design is adaptable, and it might be used to convert highways or buildings into renewable energy sources. The way of mixing the base materials to generate a supercapacitor, according to the experts, is the key to the novel design.
Researchers have already sought to imbue structural materials with battery-like capabilities by combining concrete with graphene-based carbon nanotubes. However, nanotubes are costly to manufacture and are not easily scalable for real-world applications. Carbon black, on the other hand, is a substance made from the incomplete combustion of coal, vegetable waste, or fuel, and it provides a more cost-effective alternative to nanotubes due to its widespread availability.
The researchers discovered that when carbon black is combined with water and cement, it produces a "fractal-like," electron-conducting network. They then formed the final product into small plates 1mm thick by 10mm wide and enclosed it in a potassium chloride membrane, a common electrolyte material, to form a sandwich-like structure.
According to the researchers, two electrodes composed of this material are separated by an insulating layer, allowing them to form a very powerful supercapacitor. When powered, the plates can illuminate a succession of LED lights. The researchers believe that the new substance might be used to store a day's worth of energy in roadways or buildings.
Even if the basic combination functions as a supercapacitor, keeping its energy-storing capability as well as structural strength can be difficult. Increasing the amount of carbon black increases the amount of stored energy, but the concrete weakens. The researchers discovered that using roughly 10% carbon black in the mix is the sweet spot for foundations or other structural elements.
When structural strength is not an issue, the amount of carbon black in the supercapacitors could be raised to make even more potent supercapacitors. Franz-Josef Ulm, a civil engineer at MIT, is now working on developing a 12V battery comparable for automotive purposes. The prototype might be ready in 18 months and could even be used as an elemental brick for energy storage in homes.