Charge your devices with a sweaty run in the sun
Image of a proposed prototype of a wearable electric power biodevice in the form of a bracelet.
Just imagine a wearable device that is powered by the sun you soak up while you take a jog, then uses the sweat you perspired as a power source when the sun has faded. It is the ambition of a Malmö University professor with a goal to provide a greener alternative to existing batteries.
Replacing batteries — which we are using at an unsustainable level — is the aim of Professor Sergey Shleev, a researcher at Biofilms Research Center for Biointerfaces.
If you are using both chemical and solar energy, you are more or less ‘fuel independent’.
Professor Sergey Shleev
“The problem is that we use batteries in many different ways, and they are not environmentally friendly. There are many disadvantages with batteries, such as how heavy they are, and it is predicted that in the near future we will have more and more demand for them in our lives. If we really want something portable, something useful, we have to think how to get rid of batteries,” says Shleev.
As it stands, it is “scientifically difficult” to replace, for example, lithium batteries because they have so many positive attributes; greener, more sustainable alternatives have the main drawback of low power and output.
“While we are unable right now to replace any battery, we are driving this research and we are hoping that one day we will be able to do so. Many different scientific groups are working in this direction, but I think ours has quite unique selling points.”
The research team utilise a supercapacitor which can not only transform different types of energy into electrical energy but can also simultaneously store this energy in the same unit, this is one of the its unique selling points, the other is the fact that it uses dual energy sources.
“We are trying to utilise two different types of energies: chemical and solar. Both have their advantages and disadvantages. We know, solar energy is not constantly with us, so when it is dark, no energy!
“If you are using both chemical and solar energy, you are more or less ‘fuel independent’. If you have enough energy to accumulate it and store it in the same model, it is not wasted, and you can use it later on.
“We are working with mostly biological energy sources; sweat, for instance, contains a lot of energy-rich compounds like lactate and glucose, and these compounds are how your body functions as you oxidise glucose. You have this process inside your body; similarly we use glucose and lactate to generate electrical energy but use electrodes and not cell processes,” says Shleev.
The research team has now designed and tested several different types of prototypes and are aiming to make electric power biodevices for harvesting and storage of chemical and solar energies more portable and more powerful.
“We want as high as possible voltage and as high as possible power. Our ultimate goal is to power real gadgets,” he adds.
Text: Adrian Grist