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Samsung Nanotech Breakthrough Nearly Doubles Li-Ion Battery Capacity
The Korea Times reports that Samsung researchers have published in Nature Communications the results of research (here's the abstract) that could lead to vastly greater storage capacity for lithium-ion batteries. The researchers, by growing graphene on silicon anodes, were able to preserve the shape of the anodes, an outcome which has formerly eluded battery designers: silicon tends to deform over numerous charging cycles. From the linked abstract: Here we report direct graphene growth over silicon nanoparticles without silicon carbide formation. The graphene layers anchored onto the silicon surface accommodate the volume expansion of silicon via a sliding process between adjacent graphene layers. When paired with a commercial lithium cobalt oxide cathode, the silicon carbide-free graphene coating allows the full cell to reach volumetric energy densities of 972 and 700Whl1 at first and 200th cycle, respectively, 1.8 and 1.5 times higher than those of current commercial lithium-ion batteries.
Also at ZDNet.
So when will I be able to buy an electric supercar for $20K? Until then, I'm not interested, and neither are millions of people.
And battery capacity just doubled last week! It's amazing that they can keep releasing breakthrough after breakthrough!
How can I believe you when you tell me what I don't want to hear?
For those cozy nights by the fire.
Watt-hours per liter. Units, stuff that matters.
to make half as thick phones, instead of phones that last twice as long...
The Cloud - because you don't care if your apps and data are up in the air.
Yes, but you have to start it with gas/diesel. That is the only way to get a real bang for the night.
I prefer the "u" in honour as it seems to be missing these days.
Any theories for why Tesla's stock price didn't pop on this news?
There have been scores of purported breakthroughs in this subject over the last ten years, but nothing dramatic has as yet hit the market. There have of course been noticeable improvements - but I still have to recharge my phone every night, and a decent range in an electric car will still set you back to the tune of nearly $100K. We'll see whether this is really becomes a breakthrough, or whether it is just another incremental step forward.
That's not what it says. It says that the capacity at 200 cycles is 1.5x a current cell. No mention is made of the point at which the capacity of these cells drops below the capacity of regular cells, if indeed such a point even exists: it's entirely possible these cells have roughly the same performance vs cycle curve as current cells after 200 cycles, just with a generally higher capacity.
I suppose you might raise the question of why they limited their testing to 200 cycles rather than more, but I note that if each charge/discharge cycle takes 4 hours then 2000 cycles would take almost a year to complete.
The value of 1.5 is equal to 2 for small values of 2.0
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Right, 200 cycles is too short. These don't even compare well with Panasonic's current NCA cells, which are reported as 675 Wh/l. After 300 cycles the Panasonics probably store more energy.
a,e,i,o,u and sometimes w and y (at be if of up cwm by)
I'd take a 200 cycles more powerful battery over a 2000 cycles less powerful battery any time. I'm not sure why you view changing a battery once or twice a year as such a big deal.
I saw that number written on the bathroom wall at the club I was at last night. You must get around.
Because 200 cycles need about 200 days?
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
There's news like this every week. None of these is clearly better cheaper or faster to market than any other breakthrough like it at this early stage. It all evens out to a fairly steady improvement over time. Battery weight and prices still keep halving every five years or so and that's already factored into stock prices, minus some risk.
On the other hand, if they're doubling capacity, then you only need half the number of cycles (it actually even works *better* than that, as li-ion cells prefer shallow charges and discharges rather than deep ones - but yes, fractional charge cycles do add up as fractional charge cycles, not whole cycles). If you have a 200km-range EV and you drive 20 kilometers a day, you're using 10% of a cycle per day. If you have a 400km-range EV and you drive 20 kilometers a day, you're using 5% of a cycle per day.
Dear Lord: One of your creatures may be hurt tonight. Please let it be the other creature.
Keep in mind that for widgets like phones and tablets that they are not always cycling fully on a daily basis. Lithium Ion batteries degrade much faster being deep cycled from 100% to near 0% than if you are only going 80% to 20%, like an order of magnitude longer. Most applications do not ever fuly charge the cells, and shut down before hitting zero to trade off a little capacity for vastly longer useful lifetimes.
On the other hand, if they're doubling capacity, then you only need half the number of cycles
I'm pretty sure I saw an episode of Red Dwarf where they made a similar trade off... It ended up with Lister playing pool with planets.
Don't be like Lister.
#DeleteChrome
Jenny? Is that you?
I'm not sure why you view changing a battery once or twice a year as such a big deal.
It's because it generally means replacing your whole phone these days.
What's the power density? (Amount of energy delivered over time)
That's not power density. That's just power. Power density is how much power (energy delivered over time) it can deliver per unit volume of battery. That's really only of concern for high power applications such as an electric race car. For most usages, energy density is far more valuable.
Note that the paper says the capacity 1.8x at the beginning and 1.5x after 200 cycles. The smart phone batteries are rated at least 1000 cycles. Not sure what is the capacity after 1000th cycle. Until there are some numbers showing superior value at 1000th cycle, it will be hard to commercialize.
Because lots of devices don't have user replaceable batteries - eg most tablets and many phones.
Also, for lots of devices the cost of those batteries is very high, to the point that lifetime cycle cost is significant. Eg electric vehicles or off-grid storage.
But if the capacity is double, won't each cycle last double the time? So 400 days.
Wealth is the gift that keeps on giving.
Comment removed based on user account deletion
I learned something new. iPhones are seamless and this was touted as a *very* important feature. (Some stretching was made involving potential breakage and whatnot.) I wish I had thought about the sharpness of those seams. I could have helped them out by pointing out that, without seams, they would be less likely to cut themselves too. More so with them getting thinner and thinner all the time.
"So long and thanks for all the fish."
no jenny would be (301) 867-5309
Without even reading the article, I can guess what they did from my own experience: use a hole punch and flip the battery over.
-Dave
I would say, yes! But that might depend on the usage pattern.
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
You would need half the cycles to do the same amount of work, but how long would "the same amount of work" really happen though? I think manufacturers would probably add features that are prohibitively expensive from a power budget standpoint today. That's an easier and more distinguishing selling point for competition than battery life. I mean, a flip phone will go for many days without needing to be recharged, if that's someone's primary consideration.
https://www.eff.org/https-everywhere
Not really. Anyone with sufficient skill and patience can cheaply replace their own battery, and manufacturers and third parties both offer that service if you'd rather not DIY. Whether it's worthwhile, of course, depends on how new your phone is, and the cost of an upgrade, but for many people in a 2 year contract, it's much cheaper to replace the battery, even through a service, than to upgrade or replace the phone.
https://www.eff.org/https-everywhere
That's why you get a free phone when you sign a two year contract.
Which doesn't help me if the phone doesn't last 2 years.
I mean, that's why you don't "purchase" a phone on a two year contract. The company gives you a "free" phone when you sign a two year contract, or a discount on a phone if you sign the contract (but the phone purchase is independent).
Maybe it's different with your company, but no cell company I've ever heard of warrants their phones for the entire contract period (unless it happens to be 1 year and the manufacturer's warranty is also 1 year).
I usually replace my phone batteries around 2 years, or a bit earlier if they need a screen replacement (as mine does now). New batteries for iPhones usually cost about $20 and take about 10 minutes to install. Five if you've got some practice.