Imagine a world where a rechargeable battery would never have to be replaced, at least not in your lifetime.
Such a world moved one step closer to this never-say-die rechargeable battery reality thanks to researchers at the University of California, Irvine (UCI). The UCI team recently developed a nanowire-based battery material that can be recharged hundreds of thousands of times, with next to no degradation.
And the amazing part is that the new rechargeable battery technology might have been developed by accident, albeit through a lot of determination.
The research study leader Mya Le Thai coated a gold nanowire in a manganese dioxide shell and encased the assembly in an electrolyte made of a Plexiglas-like gel.
She then cycled the testing electrode up to 200,000 times over three months without detecting any loss of capacity or power and without fracturing any nanowires, a technique which paid off handsomely according to the chair of UCI’s chemistry department Reginald Penner.
“Mya was playing around, and she coated this whole thing with a very thin gel layer and started to cycle it,” he said.
“She discovered that by using this gel, she could cycle it hundreds of thousands of times without losing any capacity. That was crazy, because these things typically die in dramatic fashion after 5000 or 6000 or 7000 cycles at most.”
“We started to cycle the devices, and then realised they weren’t going to die, and we don’t understand the mechanism of that yet.”
Gold or nickel could replace lithium in batteries
Thai and her team found that their system of using gold nanowires to store electricity is able to far outlast the traditional lithium battery storage construction, a discovery which could be a game changer for the electronics industry.
The new rechargeable battery breakthrough could lead to laptop, smartphone and tablet batteries that last forever, as well as commercial batteries that could last a lifetime for use in appliances, cars and spacecraft.
In describing the new technology, Penner used the analogy of pouring water back and forth between two cups; after a few hundred transfers from one cup to the other some water would spill out leaving less charge by the traditional lithium battery, whereas the new nanowire based technology could transfer the water between the cups 200,000 times while only losing 5% of the liquid.
UCI researchers think the nanowire batteries are so effective due to the electrolyte made of Plexiglas-like gel plasticizing the metal oxide battery, giving it flexibility and preventing it from cracking.
“The coated electrode holds its shape much better, making it a more reliable option,” Thai said.
“This research proves that a nanowire-based battery electrode can have a long lifetime and that we can make these kinds of batteries a reality.”
Commercial rechargeable battery still some time away
While this reality looks promising, this technology which promises consumer electronics that last 400 times longer relies on an initial test platform which isn’t a true rechargeable battery.
Batteries have an anode, which allows electricity into the system, and a cathode which outputs electricity.
UCI researchers linked two cathodes together which alternate charging each other instead of having both a cathode and an anode, with this continuous cycling between the two cathodes making a perfect system for repeated charging.
The potential reality of nanowire based batteries which use gold will be more expensive, no matter how small the gold nanowires are, which has resulted in the UCI research team experimenting with nickel to see if they can achieve similar results.
Experimenting with nickel will allow the team to try to modify the battery system to make it more practical and affordable for real-world applications such as mobile phone batteries.
UCI’s study which lead to the creation of the nanowire based technology was conducted in coordination with the Nanostructures for Electrical Energy Storage Energy Frontier Research Center at the University of Maryland, with funding from the Basic Energy Sciences division of the US Department of Energy.
The UCI team’s findings for a potential endlessly charging battery were recently published in the American Chemical Society’s Energy Letters.
The UCI research team’s future work will focus on building actual batteries with this technology and further investigating why the gold nanowire process works.
The UCI researchers hope that further work on their nanowire-based technology breakthrough will usher in a new era of rechargeable batteries that never need to be replaced.