A mattress made of tree pulp could one day charge your mobile phone, according to cutting-edge research from KTH, the Swedish Royal Institute of Technology. Source: The ABC
The researchers published a scientific paper in the latest issue of Nature Communications describing the process of turning trees into squishy foam that has the current-holding ability of batteries.
The creators of these batteries say the technology is scalable and if it is economically viable we could see flexible, shock-resistant batteries providing a spongy filling for clothes, cars and even mattresses.
One of the researchers on the project, Dr Mahiar Hamedi, described the properties of the new battery.
“The result is a material that is strong, light and soft,” Dr Hamedi said. “The material resembles foam in a mattress, though it is a little harder, lighter and more porous. You can touch it without it breaking.”
The scientists built the batteries out of nanocellulose, an extremely dense yet light gel derived from wood fibres.
The process involved first reducing wood pulp by about a million times in order to produce nanocellulose, freezing it, then transforming the liquid into a gas through freeze-drying, thereby creating what is called an ‘aerogel’.
The result is a flexible and compressible, porous material that is quite hardy.
The batteries are produced by coating the entire interior surface area of the aerogel with ink that conducts electricity.
While similar technologies are currently available, they lack the shock resistance that makes these batteries so useful.
“We use already lots of materials in products to add shock absorbance, insulation, or making the products soft. For example in beds, toys, cushions, foams in the interior of cars, and so on,” Dr Hamedi said.
“The main advantage, I think, is to now allow for function to be added to these materials that already have to be there anyway. In cars this could mean extra energy storage with almost no increase in weight or compromise with function.”
This advance is the culmination of a three-year study, where scientists in Sweden and the US have been researching the production of 3D batteries.
One of the biggest benefits of these 3D batteries is the increased surface area, allowing for huge energy storage potential.
“We are no longer restricted to two dimensions,” Dr Hamedi said. “We can build in three dimensions, enabling us to fit more electronics in a smaller space.”
As attention shifts towards renewable energy, solar power in particular, we will see an increasing need for versatile battery production that can be sourced from renewable materials. This new technology could be a first step towards that goal.
“The aerogel is renewable. In the systems we have presented all the materials are renewable,” Dr Hamedi said.
The push for novel battery technology coupled with the relative low cost of the materials may mean that these batteries are available sooner than we might expect. Dr Hamedi says that we will probably see the technology in 5 to 10 years, a relatively short turnaround in the world of scientific discovery.
