Nanotechnology turns Bricks into Batteries
Research could pave way for cheap supercapacitor storage of renewable energy
A team of researchers at Washington University in St Louis created small prototypes of ‘power bricks’ which are able to power small LEDs. The bricks were made by using chemical vapours to react with the red iron oxides in the bricks which forms a network of plastic nanofibres. The energy density is only about 1% of that of lithium ion batteries, but is believed this can be increased by tenfold. A brick costs only about 3 dollars to make.
This article is taken from the Guardian and added upon. For the original, click here.
A brick supercapacitor powering an LED light. The porous nature of fired red house bricks has made it possible for researchers to fill the pores with nanofibres of conducting plastic. Photograph: D’Arcy Research Laboratory.
How it’s made
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. A team of researchers at Washington University in St Louis created small prototypes of the power bricks using chemical vapours to react with the red iron oxides in the bricks and which 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.
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. The bricks can be produced at 3 bucks a pop.
Not batteries but supercapacitors
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. 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. 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. “A solar cell on the roof of your house has to store electricity somewhere and typically we use batteries,” said Julio D’Arcy, at Washington University in St Louis, US, who was part of the research team. “What we have done is provide a new ‘food-for-thought’ option, but we’re not there yet.”
It ain’t much, but it’s honest work
The energy density of the first power bricks, reported in the journal Nature Communications, is just 1% of that of lithium ion batteries. D’Arcy believes this can be increased tenfold by adding materials such as metal oxides to store more charge in the brick, which would also make the power bricks a commercial proposition. But the hope is to eventually match the energy density of lithium ion batteries. “If so, this technology is way cheaper than lithium ion batteries,” D’Arcy said. “It would be a different world and you would not hear the words ‘lithium ion battery’ again.”
Dan Brett, a professor of electrochemical engineering at University College London, UK, said: “Heat has been the overriding area of interest when considering energy storage within the fabric of buildings. This study shows there is potential to store electrical energy as well. The performance is a long way short of bespoke supercapacitors, but the principle is proven and there is significant scope for improvement.”
Why are we not funding this?
The charge stored by the first bricks is too small to give a shock when touched. But a wall of connected bricks would need an insulating coating and the scientists demonstrated this using epoxy resin, which even allowed the bricks to work underwater. The reactions used to create the power bricks may have a small weakening effect on their structural properties, D’Arcy said, but in any case bricks were most commonly used today in houses as decorative facades.
Richard McMahon, a professor of power electronics at the University of Warwick, UK, said the research was intriguing. “Energy storage is of great contemporary interest, especially in the electrical form. [But] although this work is an interesting demonstration of a possibility, it is a long way from practical application.” What’s more, the cost of lithium ion batteries has plummeted by 90% since 2010, and heavy hitters in the industry like Tesla and Panasonic are pumping billions into lithium. This might leave many potential investors skeptical about this technology, as it would still need to be scaled to outside the lab.
Nevertheless, transforming commonly used building materials into energy storage devices might just be one of the keys in accelerating the energy transition.
A device comprising three Pedot-coated brick supercapacitors and connected in series lights up a white light-emitting diode, but quickly fades away. Credit: Wang et al.
References & Further Reading
SingularityHub - Scientists Found a Way to Turn Bricks Into Batteries
Futurism - They turned a brick into a battery
Scientific American - Bricks can be turned into batteries