First published July 1, 2022.
Researchers at the University of California, Irvine (UCI) built a nanowire battery electrode that survived around 200,000 charge and discharge cycles over three months without measurable loss of capacity or power. Similar nanowire electrodes usually fail after 5,000 to 7,000 cycles. The trick was a thin coating of a Plexiglas-like gel. The work was announced in April 2016 and published in the American Chemical Society journal ACS Energy Letters.
The result is often summarised as "a battery that lasts a lifetime". That headline goes further than the science. Here is what the team actually made, why it matters, and what it does not yet mean for your phone or car.
What the UC Irvine team discovered
The study was led by Mya Le Thai, then a doctoral candidate at UCI, with chemistry department chair Reginald Penner as senior author. Thai was experimenting with electrodes built from extremely thin wires and decided to coat one of them in a gel electrolyte before cycling it. To the team's surprise, the coated electrode simply kept going.
Penner described the outcome in UCI's announcement in one memorable phrase: "That was crazy." The usual expectation for this kind of structure, he explained, is a sudden and dramatic failure after a few thousand cycles. Thai's sample passed 200,000 cycles with no fractured nanowires.
The research was carried out with the Nanostructures for Electrical Energy Storage Energy Frontier Research Center at the University of Maryland and funded by the Basic Energy Sciences programme of the US Department of Energy.
Why nanowires are attractive, and why they usually break
A single nanowire is far narrower than a strand of hair, by a factor of thousands. That tiny diameter gives them an enormous surface area relative to their volume, which is attractive for energy storage: more surface means more places where ions and electrons can move in and out, allowing fast charging and high power.
The downside is fragility. Every time a battery charges and discharges, the electrode material swells and shrinks slightly as ions enter and leave. In a thin wire, those repeated stresses lead to cracking. Once the wires fracture, they lose electrical contact and the electrode's capacity falls quickly. This is the main reason nanowire batteries have stayed in the laboratory despite decades of interest.
How the gel coating changed the result
The UCI electrode used a gold nanowire as a conducting core, wrapped in a shell of manganese dioxide, a common battery material that stores the charge. The whole structure was then encased in a gel electrolyte based on poly(methyl methacrylate), or PMMA, the polymer better known as Plexiglas or acrylic.
The researchers believe the gel softens, or plasticises, the manganese dioxide shell, making it flexible enough to cope with repeated swelling and shrinking without cracking. Thai summed up the benefit simply: "The coated electrode holds its shape much better, making it a more reliable option."
A common mix-up in coverage of this story is worth clearing up: the shell material is manganese dioxide, not magnesium oxide. The two are easily confused in print but are entirely different compounds.
Myth check: does this mean a battery that never dies?
Not yet, and possibly not in this form. Several points are often lost in the headlines:
- It was an electrode, not a finished battery. A working cell needs two electrodes, a separator, packaging and safe operation across temperatures and loads. The test showed that one component could survive extreme cycling.
- Lab conditions are gentle. Controlled tests do not include the heat, vibration, deep discharges and years of calendar ageing that real devices face.
- Gold is expensive. Cheaper conducting cores, such as nickel, have been suggested, but they would need to be shown to perform as well.
- Energy capacity matters too. Long life is only one requirement. A useful battery also needs to store enough energy for its size and weight.
- It was not 2022 news. The result dates from 2016 and has been recirculated many times since.
UCI suggested the work could eventually lead to much longer-lasting batteries for computers, smartphones, appliances, cars and spacecraft. That remains a possibility rather than a product.
How this compares with the batteries we use today
The lithium-ion batteries in phones and laptops are usually designed to keep about 80% of their original capacity for a few hundred to around a thousand full cycles, after which users notice shorter runtimes. Electric vehicle batteries are built to last far longer, often many years, partly through careful thermal management and by avoiding the extremes of full and empty charge.
Against that background, 200,000 cycles sounds astonishing, and in materials terms it is. The real significance of the UCI study is that it challenged a long-held assumption that nanowire electrodes are inherently too fragile to be practical. It showed that the right surrounding material can dramatically change how a nanostructure behaves under stress.
Making your current batteries last longer
While lifetime batteries remain a research goal, a few habits genuinely help the lithium-ion cells you already own:
- Avoid leaving devices in hot places such as a car dashboard in summer; heat speeds up chemical ageing.
- Where your phone or laptop offers an optimised or limited charging setting, use it, as it reduces time spent at 100%.
- Store devices you will not use for a while at partial charge rather than full or empty.
- Use reputable chargers; fast charging is generally fine on modern devices designed for it.
The nanowire research is a reminder that battery progress often comes from small, unexpected discoveries in the lab. Turning those discoveries into everyday products is the slow and expensive part.
Sources: UC Irvine News, 20 April 2016: All powered up; ACS Energy Letters (2016): the published study. The story was first shared via IFLScience.
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