The humble house brick has been turned into a battery that can store electricity, raising the possibility that buildings could one day become literal powerhouses. The new technology exploits the porous nature of fired red bricks by filling the pores with tiny nanofibres of a conducting plastic that can store charge. The first bricks store enough electricity to power small lights. But if their capacity can be increased, they may become a low-cost alternative to the lithium-ion batteries currently used.
Strictly speaking, the power bricks are supercapacitors rather than batteries. Supercapacitors store electricity as a static charge in solids, rather through chemical reactions as in batteries. The advantage of supercapacitors is that they charge and discharge far faster than batteries, but to date they can only hold a small fraction of the energy. Researchers around the world are working to increase the energy density of supercapacitors, as well as the charging speed of batteries. Finding better ways to store electricity is a crucial part of fighting the climate crisis, as it would allow abundant but intermittent renewable energy to be stored until it is needed.
The researchers created small prototypes of the power bricks using chemical vapours to react with the red iron oxides in the bricks and then to form a network of plastic nanofibres. A special plastic, called Pedot, was used as it is a very good conductor of electricity. The reactions turned the red bricks a dark blue colour. Another advantage of supercapacitors is that they can be charged and recharged many more times than batteries before losing their ability to store electricity. The power bricks can be cycled 10,000 times before their capacity falls significantly.
Source: Guardian
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