The weird future of batteries
Researchers are looking to odd sources of inspiration for battery innovation, from nuclear waste to your gut. We reveal five of the strangest projects
Innovation inspired by mould and... your gut.
Inspiration for new battery tech comes from the weirdest places: tattoos, intestines and a girl’s best friend. Here are five ways researchers are looking to spark innovation.
Easy to digest
We have a gut feeling you’d be pleased if your phone battery lasted five times longer. It’s an improvement promised by researchers at the University of Cambridge, who have solved one of the hurdles holding back lithiumsulphur batteries: degradation of the materials in the electrodes, which reduces their longevity.
Inspired by the villi cells lining the intestine, the researchers added tiny fingers of zinc oxide to the surface of one of the electrodes, helping to trap the material inside the battery and keep it working for longer. “By taking our inspiration from the natural world, we were able to come up with a solution that we hope will accelerate the development of next-generation batteries,” said the lead author, PhD student Teng Zhao, in a statement.
Such lithium-sulphur batteries offer five times the energy density of lithium-ion versions, but won’t be commercially ready for years to come.
Mouldy bread
Speaking of stomach-turning, the fungus that causes bread mould could lead to rechargeable batteries, say researchers at the University of Dundee. The fungus Neurospora crassa – or red bread mould – can manage the trick of transforming manganese into biomass materials that work well as supercapacitors.
“In comparison to other reported manganese oxides in lithium-ion batteries, the carbonised fungal biomass-mineral composite showed an excellent cycling stability and more than 90% capacity was retained after 200 cycles,” said Professor Geoff Gadd, head of the Geomicrobiology Group at the University of Dundee, suggesting mould could help extend the lifespan of rechargeable batteries as it shortens the life of your bread.
Diamonds are nuclear waste’s best friend
If you shove nuclear waste inside a diamond, it can power low-current devices without any recharging or emissions. That extreme idea comes via experts at the University of Bristol, who showed a working prototype at the end of 2016, embedding Nickel-63 inside a man-made diamond and using it to generate a small current. The aim is to shift to a new nuclear material, Carbon-14, which is a waste material created in nuclear power plants.
“There are no moving parts involved, no emissions generated and no maintenance required, just direct electricity generation,” said Tom Scott, professor in materials at the Interface Analysis Centre, in a statement. “By encapsulating radioactive material inside diamonds, we turn a long-term problem of nuclear waste into a nuclear-powered battery and a long-term supply of clean energy.”
The nuclear-powered diamond batteries generate a tiny amount of current but last a phenomenal time: a battery with one gram of Carbon-14 would offer less power than an AA battery, but would take 5,730 years to reach 50% power. That means they won’t be used in your phone, instead finding a home where it’s more difficult to replace batteries. “Obvious applications would be in low-power electrical devices where long life of the energy source is needed, such as pacemakers, satellites, high-altitude drones or even spacecraft,” said Scott.
Clear vision, fast charges
Slow charge times are a pain point for power-hungry devices, but experts from the universities of Bristol and Surrey have found one solution – inspired by contact lenses. Working with local firm Augmented Optics, they developed a supercapacitor, which is an alternative to batteries for holding power. They charge and recharge quickly, but have poor energy density so require larger form factors to be useful.
Researchers believe they’ve found a way to change that by boosting density using flexible polymers, similar to those in soft contact lenses. These could let phones or electric cars be recharged in seconds. Jim Heathcote, CEO of Augmented Optics, hopes we won’t have to wait long: “The test results from the new polymers suggest that extremely high energy density supercapacitors could be constructed in the very near future.”
Mould could help extend the lifespan of rechargeable batteries as it shortens the life of your bread
Biofuel tattoo
Sadly, the reminder of the affection you hold for your mother that’s inked on your skin won’t power a smartphone, but researchers at the University of California, San Diego, have created a temporary tattoo that’s also a biofuel battery cell.
The researchers were looking for a way to measure lactate in sweat to avoid subjecting people to blood tests, but found a way to create power from the chemicals on your skin gathered via a temporary tattoo.
“The current produced isn’t that high, but we are working on enhancing it so that eventually we could power some small devices,” said Wenzhao Jia, a postdoctoral fellow at the university.
Don’t worry if you’re out of shape: those who were less fit produced more power because they form more lactate.