Samsung Develops Battery Material with 5x Faster Charging Speed(news.samsung.com) |
Samsung Develops Battery Material with 5x Faster Charging Speed(news.samsung.com) |
The trickiest part looks like the chemical vapor deposition of graphene onto SiO2 nanoparticles. CVD is a slow growth process that I normally see applied to creating precise, thin layers on flat substrates. I think it would be hard to scale this up to industrial (tonne per day) quantities of coated particles. Is it possible to replace that process with something like a fluidized bed reactor? I'm out of my depth here regarding paths to scale-up -- I have a chemistry background, but I'm not qualified to comment on most chemical engineering.
Wow, this might be one of those rare instances where new research is gonna proceed rapidly into industry. The paper[1] isn't shy about it either. This is great on all fronts: increases cycle life, charge speed, and even marginally increases capacity. They're very optimistic about integrating it into production lines and it seems cost-effective. Cheap, even. The inputs are methane and fumed silica into a 1000 C furnace- you can practically buy those at a hardware store and then it just gets mixed into the r2r slurry.
I think it's pretty likely that charge speeds are about to increase handily. Fig. 4 shows the battery with additives charging at 5 C compared to virgin chemistry at 1 C. That's about 5 minutes to charge the middle 50% of a battery- incredible. Still remains to be seen if this is compatible with standard additives and SEI conditioning, but I'd be surprised if it didn't work out fine.
I feel the same about the CVD but it looks like it was fast and easy from the paper (as much as I recall right now). Certainly way less exotic than most CVD.
Could have fooled me.
I applaud you, sir, on your awareness of self and awareness of scale. If only all programmers were as self aware and aware of the difference between a background in programming and software engineering at scale, I'd smile a little more.
For reference, I used to see ~4 hour cycle times for growing graphene on copper sheets. I think most of that was in the heat up and cool down, maybe order of 30min actual growth time. These numbers might be off by a factor of 2-5, it's been a few years since that job, and I was a equipment design engineer not a process guy as such.
Compared to other Battery tech advance from University Research and Startup which are trying to hype and gain new funding, Samsung doesn't need that. And my guess it is at least small scale production ready before they make such announcement. ( Or they knew a competitor which has a similar product announcement soon and step up ahead of them )
Hopefully we see this in shipping product by 2020.
800 / 2.5 would be 320 Wh/kg.
800 / 3.0 would be 267 Wh/kg.
Both numbers are quite good, as batteries go, but not an order of magnitude higher than what's available now.
I thought I was watching an episode of Flash for a moment.
Experts were skeptical[1] that their recharge rates and capacity were possible with current gen tech...unless Elon knew something they didn't.
[1] https://www.bloomberg.com/news/articles/2017-11-24/tesla-s-n...
Isn't this only necessary because Lithium-Ion batteries need it to maintain efficiency and longevity? Is this also an issue with graphene?
Edit: better source here https://www.nature.com/articles/s41467-017-01823-7
The growth process is the only remaining question, but it seems very tame. Methane is the carbon feedstock, and the furnace is only 1000 C. It doesnt have the pitfalls of normal graphene production because they arent concerned about monolayers etc- I would say their product has a lot more in common with expanded graphite than graphene. Because of that I expect its similar in cost to synthetic graphite, which is roughly equal to natural graphite.
Observe the noticeable lack of any mention of how many cycles a cell will last at this charge rate. It is well known that ordinary li-ion cell can be charged extremely fast too, as long as you don't charge so fast it heats up rapidly and goes into explosive thermal runaway, but it shortens the lifetime considerably.
Problem is that this graphene layer is extremely thin, one atom. Mass-production, what they claim to do, would be a killer app for much more than just batteries, but for batteries it's the easiest win.
For cars, having twice the capacity with the same charge speed would be enough, since you can charge slowly when you sleep, what matters is that the car can handle the distance you can travel in a day.
10 years ago PERC cells weren't available on an industrial scale, even though the technological basics were discovered, explored at the lab scale, and published in the 1980s. It took a lot of manufacturing advances and market evolution before PERC technology was both practical and profitable to manufacture for large scale use.
http://www.aleo-solar.com/perc-cell-technology-explained/
Likewise, I expect that some battery ideas that are published and "go nowhere" will eventually reach industrial scale, but only much later.
We have been spoiled by the web to expect a whole other time scale, but physical technology still takes the time it has to take.
My - not very informed - impression is that battery technology actually is moving very fast, considering the timescale constraints.
That's precisely the sort of thing that most manufacturers don't want, because a battery designed to last effectively forever means less recurring revenue on replacements.
"100% recyclable" is good for them (and "biodegradable" even better), because they can act "green" while continuously making products that don't last and have to be recycled, expending even more energy and creating profit in the process. "The best kind of planned obolescence is environmentally friendly planned obolescence."
That's ridiculous, tinfoil hat thinking. Longer cycle life = cheaper battery = higher profit + happier consumer.
Those breakthroughs, when applied to scaled up battery manufacturing give us the 5%-10% compounding annual improvement we see. A doubling at least every 15 years is pretty good!
> A full-cell incorporating graphene balls increases the volumetric energy density by 27.6% compared to a control cell without graphene balls, showing the possibility of achieving 800 Wh L−1 in a commercial cell setting, along with a high cyclability of 78.6% capacity retention after 500 cycles at 5C and 60 °C.
In your other comment you write:
>the standard is 80% capacity after 500 cycles at the normally specified (1C) charge rate
So I'd say that's pretty good.
Does that mean 5C Charge rate and > 5C Discharge? Because in the EV Market 5C discharge would be borderline enough (I think Teslas 18650 discharge at a peak of 20A per ~3,5Ah Cell so 5C Discharge would be cutting it very close.)
If it's 5C Charge and getting to 500 cycles with higher discharge then...woah.
Heres an "entry" article: https://kabru.eecs.umich.edu/wordpress/wp-content/uploads/St...
and you can follow the references from there (into SciHub etc. if need be.)
I dont have any data on newer iPhone 7 and 8 / X.
Here's the most general possible one: only lithium. Each lithium atom gives up one electron, at some voltage. The standard electrode reference voltage of lithium is 3.04 volts. That works out to 26.8 amp-hours per mole, and 81.47 Wh/mole. A mole of lithium weighs 6.941 grams. The end result is 11.74 kWh/kg. That's the absolute, utter maximum energy density for a closed system battery (which is why li-air can exceed that figure).
I am continually surprised by how quickly capacity keeps increasing towards that. Battery capacity will easily double with tech quite similar to current, and 10x would not surprise me within my lifetime.
Start by reading about the Phoebus cartel: https://spectrum.ieee.org/tech-history/dawn-of-electronics/t...
I remember my first electric razor. It failed after a couple of years, so I took it apart to find out why. I discovered that the electrical contacts to the motor were just little pieces of graphite, and when they wore down to nothing the razor was finished. Definitely planned obsolescence in action!
(Search YouTube for "vintage induction motor" and you'll find plenty of century-old(!) examples still in good running condition. I don't think the same can be said of the brushless motors today.)
- Al Bartlett
If we thought in 100D, we might have a better sense for it, because we'd be able to see a hundred of them.
Hypervolume grows exponentially.
One way to get a really rough idea is to try and control each and every joint individually.
Close your eyes and try to imagine that each joint, each muscle is a dimension along which you can move (by moving it), and your posture at any given moment is a point in that space. When you move, you make a line through it. Don't picture it, just feel it.
What is the shape of that space?
You can get an idea of what exponential growth is like by exploring how the shape of that space changes as you add more and more things you're controlling.
https://en.wikipedia.org/wiki/Brushless_DC_electric_motor
AFAIK there is no substitute for graphite in a brushed motor, it is needing to transfer power to different sections of a rotating part in turn and does so by rubbing over a set of copper strips. That the graphite is soft is why it works well but also why it wears out rather than the commutator, which will survive several sets of brushes.
> ... In the case of a discrete domain of definition with equal intervals, it is also called geometric growth or geometric decay, the function values forming a geometric progression. ...
Still, geometric growth is exponential in n when n is the number of dimensions, which isn’t really the n we were talking about in this context.
I never completely figured out Aikido with it’s joint locks and levers. Maybe talented aikidokas have a grater capacity to visualize/fill this type of activity?
Interesting point, but I don’t think Aikidoka have any special talent for that: we use a small number of techniques and what changes is the way you use them in response to different attacks/holds.
Also, you tend to work on your specific Ryu (school) technicsl curriculum and nobody goes around “inventing” new locks.
(Some argue that Aikido is not really adapting to modern world nor cross-pollinating with other martial arts due to -arguably excessive - reverence for tradition).
You can model what you're doing as a phase space, which is the product space of the state of each thing you control. This generally has a lot more dimensions than three. (You see this in robotics; a 5-axis CNC has a 5 dimensional phase space for position (5 axes of motion), plus a few more dimensions for things like speed and coolant flow.)
That mashed up with the meditation idea of starting with your focus on something really small -- the soles of your feet, for instance -- and drawing it up your body until you can feel all of it.
If you do the two, you can slowly draw yourself into awareness of higher and higher dimensional phase spaces, which shows you a curve of exponential growth.
Well, okay -- I also followed Terry Tao's excellent advice on dealing with higher dimensions, to stop trying to picture math and start trying to find systems that expressed it in what they did. You can often get a feel for a system doing something more complex than what you can directly picture.
> If we thought in 100D, we might have a better sense for it, because we'd be able to see a hundred of them.
This is pretty clearly talking about getting a better sense of the asymptotic behavior in number of dimensions, and having a better intuition if you see a hundred steps than if you see three. The three steps of exponential growth mentioned are in transitioning from a single cube, to a line of 10 cubes, to a grid of 10x10 cubes, to a block of 10x10x10 cubes. But that's sort of where we tap out, because we're so heavily wired for 3D -- if we dealt with 100D, we'd have 100 such steps we could intuitively observe, and so have a better sense of asymptotics.
This is further seen in that the exercise is based on increasing the number of dimensions to explore the growth of the space as the dimensionality changes. It's literally adding more and more terms to a product space, and so clearly dealing with issues about dimensionality.
You're simply wrong, and incredibly uncharitable in your interpretation.
Further, geometric growth isn't a power law -- it's exponential growth. So the person asking the question was indeed confused, regardless of the fact you're wrong about what I was talking about. Geometric series are r^1, ^2, r^3, etc while a power law will look like 1^x, 2^x, 3^x, etc. Asking if an exponential growth is "just geometric growth" is being confused -- they're the same thing.
I discuss how seeing 100 steps of a sequence with regular behavior gives you a better sense of its asymptotics than seeing 3 steps, and then how you can generate some steps of that sequence as a mental model.
The N that is changing is the number of dimensions, both in comparing which model gives better asymptotic intuition and in terms of constructing a phase space by adding a dimension at a time.
I'm actually unsure how you could think there's an N that's not dimension, given that the only values discussed (or changing) were dimensions.
Did I not use fancy enough language when making a point to laymen, so you assumed you knew more than me and took a really uncharitable read so you could "correct" me?
They sabotage explanations to laypeople by incorrectly nitpicking technical details because they hear informal language that sounds similar to something they know, and rush to regurgitate that fact as a "correction" without really understanding the conversation -- and will insist on doing so unless you use language too sophisticated for the audience you were trying to reach in the first place.
This actually happens with nearly every field, I just experience it most with math -- it's probably related to Dunning Kreuger or whatever.
C'est la vie.