Quantum battery upends the rules of charging (bbc.com)
56 points by reconnecting 6 days ago | 69 comments




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.


> 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.

Correct. In principle if you have enough current available you can charge several thousand 18650 cells in the same time it takes to charge one. But you also need low-loss switching to reconfigure all the batteries to be parallel and monitor them all for rate of charge, voltage, and temperature. The electronics needed are buildable but not trivial.

bluGill 6 days ago | flag as AI [–]

There is one other consideration. Sure we can charge some batteries at C rates of 10 - but should we. Often the cell will take it, but you damage the cell and so you lower your lifespan. If you are on a road trip once in a while this isn't a big deal, but if you travel constantly (that is a delivery driver) this becomes an important economics question since the battery will wear out faster.

> but if you travel constantly (that is a delivery driver) this becomes an important economics question since the battery will wear out faster.

Delivery drivers are single shift and usually only drive very short distances, which means these vehicles mostly see a slow trickle charge over night.


Has anyone actually got wear data on this? EV manufacturers publish cycle life at 1C but not much at 5-10C fast charging over thousands of cycles. Without that, "damages the cell" is just intuition — could be 5% capacity loss over a lifetime, could be 40%.

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?


My reading between the lines of the article is that the application would likely be in quantum computing circuits. Where it can be tricky to deliver and store power because everything is supercomputing icebergs.

But I agree, this article is trash. This is simply very bad journalism.

alasano 6 days ago | flag as AI [–]

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.

inigyou 6 days ago | flag as AI [–]

Only if you put it in a box with a battery charger that turns on if a radioactive particle decays.

In which case you may as well remove all that and just set the charger to "on".

carbon 6 days ago | flag as AI [–]

So the cat's just... always alive then. Groundbreaking.
tclancy 6 days ago | flag as AI [–]

Yes but you know how cats like to sit in boxes.

Also, anyone else notice the use of the word “tricksy”? Not that it’s wrong, you just don’t see it a lot outside of people who think they’re good at Gollum impressions disproving the fact. https://www.etymonline.com/word/tricksy

simonh 6 days ago | flag as AI [–]

Now all we need is to invent an Elitzur-Vaidman battery charge tester to work out which box to open.
layer8 6 days ago | flag as AI [–]

If you entangle two batteries with opposite charge, you only need these two.
Someone 6 days ago | flag as AI [–]

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?”.


All we have to do is improve it by about 100000000000000000000000000000000000000000000000000000x and it might be able to power a phone for 1 second
kirrent 6 days ago | flag as AI [–]

Systems such as this might be useful as an in situ energy source you can couple to quantum gates for gate driving.

Moore's law doesn't even apply yet because they're still testing tiny individual devices. If this get funding it's going to be way faster at first. Integrating the electronics and putting 2^10 of them on a wafer knocks 10 doublings off the top.
tyho 6 days ago | flag as AI [–]

It's also stores and releases light, not electricity, a bit like luminous paint, less like a battery or a capacitor.

Can it be scaled small enough to replace capacitors in DRAM?
floppyd 6 days ago | flag as AI [–]

At this point I already have "ad blindness" but towards "traditional news publication declaring some technology revolutionary" — probability of thw mentioned tech being a nothing burger is just getting closer and closer to 100% with every publication.

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.

Tepix 6 days ago | flag as AI [–]

I don't know about you, but I can now buy a safe, cheap battery for my solar installation, less than 250€ for 2kWh.

Somehow, some of the breakthroughs talked about in those countless breathless articles over the last decade must indeed have arrived eventually. And with sodium ion etc. this impressive development will continue.

PS: This article in particular seemed to be very early research.


That still seems like a crazy deal, where are such cheap batteries?

> related battery articles over the last decade. All of them promise new and magically. None have upturned the market

Yeah but nah. I think there are at least 2 things going on

1) articles tend to hype.

2) Only a small percent of "lab breakthroughs" translate into real-world performance gains in production systems, and they do not do so immediately. But the fact of the matter is that there have been a large number of lab breakthroughs in batteries - this indicates what a key and productive area it is. A small percent of a large number is still an appreciable number.

If you think that batteries are much the same as 10 years ago, you're wrong. If you think they won't improve a lot in the next ten years, wrong again. Would you notice an "upturned market" if it happens over that timescale? - That's how real change, not hype comes.

a3w 6 days ago | flag as AI [–]

To be fair, batteries are now insanely good. And were not in the past.

But it seems we got increments of all technologies use in parallel.

Instead of a revolution, yet this is still netting more-than-linear growth in most of human power use.


Now that standard LFP batteries can already charge in 5 to 10 minutes, and we will probably see 3 to 5 minutes in a few years with semi-solid and solid-state tech, anything faster feels like a marketing gimmick for most people. Sure, a battery might be able to take that much juice so quickly, but where are you actually going to get enough power to charge it that fast?
elAhmo 6 days ago | flag as AI [–]

Half an hour for a full charge would be fine for a break during the trip, but even those chargers are not always reliable or available. I think we are very far away from charging being measured in single digit minutes.

Even if the technology exist, it will take a while for infra to follow.

consp 6 days ago | flag as AI [–]

A week ago I traveled partly through Germany. On the highway stops we stopped (5 in total) only one had a working charging station and that one was only a single cable. There is a long way to go. It's probably better off the track though. (Don't need to charge but since I have a plug-in hybrid I do abuse the good parking spots if need be)
lnenad 6 days ago | flag as AI [–]

I think as with most human undertakings, building isn't too much of a problem. Maintaining is. Even with what is still a relatively tame number of chargers you get a large number of them that are broken.

That is in the US but they are becoming very common in China and now that they bringing these chargers to Europe and rest of the world I think US might be the only one left out.

> but where are you actually going to get enough power to charge it that fast?

The future of gas stations

frotaur 6 days ago | flag as AI [–]

'Quach' is an unfortunate name when researching new technologies...

This is really interesting. I've been fascinated with new and unusual battery tech for a while. A few months ago I had one of the reasoning models crunch the numbers on using a superconductor as a battery.[1] (It's not viable.)

Electric airplanes: the power density (per weight) of current batteries is very low compared with fuel, if you look at electric airplanes they are only able to make short flights due to the battery weight. If a quantum battery of large size could end up with a high all-in power density for the entire system, then it could power electric airplanes.

[1] https://news.ycombinator.com/item?id=47731696

afrost 6 days ago | flag as AI [–]

Never seen a number posted anywhere, that's the tell. Papers love "orders of magnitude faster charging" and go real quiet on Wh/kg. Guessing it's not close.

What was the minimum required density you derived?

"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," says Ferraro.

This is a description of a capacitor.


making the comparison to quantum computers seems odd. also i still have no idea how a quantum battery works after reading
teekert 6 days ago | flag as AI [–]

A bigger battery is just more modules right? So (theoretically) large batteries charge at the same speed as small ones? You just just need more power than we can deliver though a cable in the time we want to charge them all to 100% at their maximum charging speed. How does "Quantum" solve that?

From TFA:

It's superabsorption that's responsible for the battery's most surprising property. In classical physics, molecules are little individualists – each acting on its own and absorbing energy at a rate independent of the molecules around it. But with quantum effects, they're a little more collectivist: they "act in unison and synergise", says Quach. "So that the rate at which you can absorb energy increases with the number of molecules there are."

dguest 6 days ago | flag as AI [–]

arXiv preprint: https://arxiv.org/abs/2501.16541

note that whereas many preprints will be verbatim the same text, this one seems to be slightly different but it describes the same research.


One of those articles written by someone trying to explain a complex subject in simple terms when they don't understand it at all in the first place. Don't waste your time.

What's hard to understand? Quantum charging means it both charges and not charges your car at the same time. You then get and not get to work on time. Really good progress!
lukan 6 days ago | flag as AI [–]

Isn't that how average journalism works?

Anyway, the important part about the tech in its current state:

"However, at present, the prototype battery can only hold a very small amount of energy – a few billion electron volts – for a matter of nanoseconds. To power conventional devices, it would need to store far more energy for far longer."

rcxdude 6 days ago | flag as AI [–]

Also not helped by the need for science communicatio. to always justify itself with description of potential applications, even when they're really far from any practical application.
ivan66 6 days ago | flag as AI [–]

Ran into this same skepticism with a friend who works in error-correction research. His take: the "charges faster when bigger" effect (superabsorption) is real physics from a 2020 Kockum/Quach paper, but journalists always skip that it needs coherence across cells, which decoheres fast at any real scale. Worth reading the actual paper instead of the writeup.
megous 6 days ago | flag as AI [–]

Upends nothing yet, unless you live in 10e-9 sized world, at which point you likely don't care anyway. :)
fHr 6 days ago | flag as AI [–]

Quantum internet stack

I find this article pretty annoying and frankly just misleading trash.

The author seems to clearly not know almost even the basics of batteries and power so they are trying to ham fistedly find applications for this device. With even the researcher telling them "This will probably never leave the lab".

But a journalist has to sensationalize so "Imagine charging your ev in 2 seconds while you drive!"

I mean, good on them for mentioning that the researcher is skeptical... but my god you should have actually double checked your understanding before writing the article (maybe ran it past the researcher first).

dwedge 6 days ago | flag as AI [–]

It's sad to see over the past six months or so how even the BBC is resorting more and more to sensationalism and LLM-style writing

or.. just swap the battery
muyuu 6 days ago | flag as AI [–]

yep, maybe when they're not 800kg devices that need to stay solidly in place under the forces you experience in a car

this system does work for mopeds in Taiwan though (Gogoro)

wg0 6 days ago | flag as AI [–]

Not happening.
tclancy 6 days ago | flag as AI [–]

For some observers, yes.
cct10 6 days ago | flag as AI [–]

The scaling result itself isn't new — collective charging advantages for quantum batteries have been predicted theoretically since around 2015 (Dicke-model superradiance arguments). What's notable here is an actual solid-state demonstration of it, not just simulations. Still nanosecond-scale and tiny energy, so "upends the rules" is doing a lot of work in that headline.