World's first quantum battery charges faster the bigger it gets
Quantum battery upends the rules of charging

Scientists at Australia's CSIRO have unveiled the world's first working quantum battery prototype. Unlike conventional batteries, it charges faster as it grows larger, thanks to a quantum effect called superabsorption. The battery uses an optical microcavity filled with organic dye molecules and a laser, and works at room temperature. While it currently stores only a tiny amount of energy for nanoseconds, researchers believe such batteries could one day power quantum computers or even electric vehicles, though skeptics question their real-world viability.
It's very counterintuitive.
- jillesvangurp
This sounds more like a capacitor than a battery. That might still be interesting but probably not for automotive applications any time soon.
> Everyone knows that the larger the battery, the longer it takes to charge
This is actually not entirely correct. Batteries are made out of cells. If you configure them in parallel, they can all charge at the same time. Increasing the number of cells doesn't increase the time to charge them. Also the charge time of individual cells has a lot to do with the chemistry of the battery.
The so called C-rate is what matters here, this is the rate at which a battery charges/discharges its capacity. C rate of 1 means its capacity (e.g. 50kwh) is charged in an hour. State of the art batteries can charge at C rates up to 8-10 now, which means they charge well below 10 minutes. What matters here is how much power you can dump in a battery without damaging it. Also, the speed at which batteries charge is usually not linear. 10-80% is usually a lot faster than the last few percent. Some Chinese batteries get to 80% in as little as 3 minutes now. The remaining 20% can take another 6 minutes.
- alasano
Put the battery in a box, when you open the box it's either charged or not charged.
Get 7 boxes and 7 batteries and you have a 99% chance of getting a charged battery every morning.
- cbondurant
I feel like (as is usual with nontechnical reporting on cutting edge science) this article isn't doing a great job at communicating the underlying tech well here. Had to independently look up some descriptions of what super absorption is, and what actually makes it a quantum effect.
Sounds like the idea is, if you've got a bunch of light emitters spaced far closer to each other than the wavelength of light they are emitting, the light output becomes quadratic on the number of emitters. as opposed to linear on the number of emitters in the standard case. And the reverse becomes true as well.
Based on that, I'm pessimistic on the potential of this, as it sounds like charging requires a conversion from electricity to light, and then discharging would also be a conversion from light back to electricity, and we don't exactly have the most lossless processes for that conversion.
Maybe useful in certain kinds of optics or laser work though, where directly dumping the stored energy as light would be desired?
- Someone
FTA:
- “at present, the prototype battery can only hold a very small amount of energy – a few billion electron volts – for a matter of nanoseconds”
- “The key point is that quantum batteries are not about storing a great amount of energy, but about delivering it faster and with greater control”
1 Watt-hour is about 2 × 10²² electron volts. That’s a factor of about 10¹³/2⁴³.
For the sake of an argument, let’s give this tech faster than Moore’s law growth, doubling in charge time and amount of charge every quarter. Then (if my math is right), we’ll have a 1Wh battery (about what an AAA battery stores) that holds its charge for about a day in 10 years.
So, what is this useful for? It can discharge way faster than it gets charged, but don’t we have capacitors for that?
Highly controlled discharging might give it niche applications, but otherwise, I wouldn’t hold my breath for this tech to power “or even your phone?”.
- 1a527dd5
I think all of us have read tangentially related battery articles over the last decade. All of them promise new and magically. None have upturned the market.
I remain sceptical.