Quantum battery upends the rules of charging
bbc.com
bbc.com
> 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.
The only reason it's related at all to battery size is because larger batteries need higher power levels in order to charge in an hour.
I'm hand-waving a bit over chemistry because you are entirely right about the C rating.
The reason my EV can't charge in an hour is because it won't accept more than around 60KW, which charges it in about 3 hours.
My car takes 240KW (It still feels insane to be delivering that much power) and 10-80% (56KWh) is about 15 minutes and 80-100% is another 15-20 minutes
That's why I find a car that only accepts 60kW and charges for 3 hours to be odd. Even if I limited my car to only 60kW, it'd take about 1 hour and 4 minutes to get 80% and another 20 minutes for the remaining 20%. So around 1 1/2 hours
(edit: fixing numbers)
It's really strange how much these older manufacturers struggle to make a good EV.
For some value of "correct" but not others. For EV's, most of the time, the "correct" thing to do is to plug it in overnight, and let the software do the rest to optimise charging. Which might look something like:
Charging to start at midnight (or whenever the cheap rate starts) and complete by 7am (or usual wakeup time) and minimise wear by charging below a fastest rate, and take the battery level from where it is now (e.g. 50%) to the configured stopping point (e.g. 80%)
This is clearly different from "charge as fast as possible and be done in 20 minutes". Although that is occasionally the requirement. But not most of the time.
Delivery drivers are single shift and usually only drive very short distances, which means these vehicles mostly see a slow trickle charge over night.
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.
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?
But I agree, this article is trash. This is simply very bad journalism.
Get 7 boxes and 7 batteries and you have a 99% chance of getting a charged battery every morning.
In which case you may as well remove all that and just set the charger to "on".
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
- “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?”.
I remain sceptical.
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.
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.
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.
Even if the technology exist, it will take a while for infra to follow.
The future of gas stations
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.
This is a description of a capacitor.
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."
note that whereas many preprints will be verbatim the same text, this one seems to be slightly different but it describes the same research.
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."
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).
I prompted sonnet with 'Write a news article about "quantum batteries"' and included the names of the researchers and it wrote a better and more accurate article than the BBC article.
It looked up the published articles and dumbed them down but also didn't misrepresent the facts.
Here's just one paragraph from the output.
> That framing matters for where the technology might actually end up first. Rather than replacing the battery in your laptop, quantum batteries are more likely to find a niche whenever a system needs an extremely fast, tightly controlled burst of energy on a very small scale — potentially useful for future quantum computers or quantum sensors that already operate in the same ultra-cold, carefully isolated environments these batteries require.
this system does work for mopeds in Taiwan though (Gogoro)