In another unusual creation, we now have functional blood batteries.
Scientists at the University of Córdoba found a way to incorporate haemoglobin – the most important bit in red blood cells – into a battery that runs between 20-30 days.
They published their findings in the journal Energy & Fuels.
The researchers based their creation on zinc-air batteries, as opposed to their more famous lithium-ion cousins. These batteries are powered by a chemical reaction where oxygen becomes water at the positive end of the battery, which releases electrodes that oxidize zinc at the negative end.
But to get a continuous reaction from the batteries, you need something to keep powering the chemical reaction.
This is where the haemoglobin comes in, the protein that carries oxygen around the body and gives blood its red colour.
‘To be a good catalyst, it has to have two properties,’ said senior author Manuel Cano Luna. ‘It needs to quickly absorb oxygen molecules, and form water molecules relatively easily.’
‘And haemoglobin met those requirements.’
In an impressive feat, haemoglobin turned out to be just the catalyst required, as just 0.165 milligrams of haemoglobin kept it alive for 20-30 days.
But don’t worry, this isn’t going to be like gold during the end times when we’re scrambling for a phone charge, but could prove revolutionary for medical equipment planted inside the body, such as pacemakers.
However, there is still some way to go. The batteries are not currently rechargeable (blood banks, anyone?), so the team is searching for something that can convert the spent material back into air.
They also won’t work in space where, of course, there’s no oxygen.
But given the drive to become more sustainable has come up with some creative ideas, we never know what the future holds.
And blood batteries may be it.