Graphene improves lithium-ion battery capacity and recharge rate by 10x | Hacker News Reader

Graphene improves lithium-ion battery capacity and recharge rate by 10x

extremetech.com

158 pointsmrsebastian71 comments

… store 10 times more power…

…after 150 charge/discharge cycles, is also five times more effective than any lithium-ion battery currently on the market

Is this the positive way of saying they lose half of their capacity after 150 cycles?

Ten times capacity is certainly a game changer for everything from wireless ear buds to electric cars, but * week-long smartphone batteries within a couple of years* sounds optimistic for something that is fabricated at the atomic level.

What exists on the market now that is designed at the atomic level and mass produced?

Silicon chips?

FWIW, the holes are created using 'a chemical oxidation process' -- which I suspect can be done on a large scale. If someone can read the actual paper and check out how they made the holes, though, that'd be cool.

Usual Li-Ion batteries get a bit over 1000 cycles, so if this is 10 times more power, it provides more power for 150 cycles than a normal Li-Ion for its lifetime.

No they don't. Degradation of lithium-ion batteries is a function of temperature, time since manufacture and charge level rather than charge/discharge cycles. If you keep the battery cool and don't discharge it below 20% or so, it will last a very long time. If you keep it hot and constantly do full discharges, it will be dead very quickly.

Since we can't control the discharging condition and rate most of the time, and today's design often stick the battery to a heat source.

Since I am no expert in chemistry, I rather point to an article here: http://batteryuniversity.com/learn/article/how_to_prolong_li...

Basically, the capacity degrades over charge/discharge cycles. The reason is pretty simple to explain, because you can't really operate the batteries in perfect condition, it always get worse while discharging and charging it.

The other conclusion of that report points to the fact that depth of discharge is related too. So instead of using it from 100% to 0% (actually 0% doesn't mean nothing left, it just means the phone can't operate on that voltage), recharge as soon as you have a plug.

You need to discharge them really slowly to if you want to keep them cool. So, there is a link between discharging and temperature assuming a high power device.

Liquid cooling for batteries wouldn't be worth it in earbuds, but it probably would in an electric car.

Which is why battery packs in Tesla cars are liquid-cooled.

Tesla battery's still get hot, just not as hot as they would get with more limited cooling.

Small aside here:

Li-ion tech is a major pain in my ass. Storing them discharged damages them. Storing them charged damages them. Keeping them topped off damages them. Fully discharging them damages them but your battery might have a protection circuit so don't worry about it. But it might not so worry about it. You've apparently got to store them half-charged for optimal lifetime but there is a lot of wrong information out there.

I think I want to power my devices with disposables, thanks :-)

Seems to me that if this proves out, and can be made affordably, the most exciting application would be electric cars -- no more range penalty vs. gasoline. Anyone know enough to comment on the likely applicability?

Most of the time these battery tech announcements will mention capacity and recharge. They are typically very silent on discharge rate and this announcement is no exception. Discharge rate is an important feature for high load applications like cars. Given that this is still lithium ion I would expect good things but it would be nice to see some high discharge data.

I was under the impression that discharge rate scaled fairly reliably with recharge rate. Is that not the case?

Not that I've seen. Charging rates usually scale with capacity. Discharge rates vary greatly.

Generally given a battery chemistry and manufacturing technology, the charge rates and discharge rates are given in units of "C" which means it allows 1A charge/discharge per Ah capacity of the battery. For instance, the lipoly batteries I got for my combat robot last year were 20C discharge, and 1C charge, and had a capacity of 1800mAh. This means I can discharge at 36A, charge at 1.8A. While true, the charge rate doesn't scale with discharge rates directly, for a given chemistry, it does.

I wouldn't be so sure about it scaling directly even within the same chemistry. Batteries can be manufactured for different purposes. I've seen 10C, 20C and even 40C discharge rates in lithium ion polymer batteries. But the charging rate usually stays under 2C.

Personally I don't really care too much about charging rates. My battery powered vehicle would be parked overnight. But I do like acceleration. And that's where discharge rates (and other problems) become an issue.

That's why I added the "...and manufacturing technology" part at the end. What I've seen is that a company will have a whole line of cells of varying capacities all at the same discharge "C" rating.

To be honest, I'm too worried about discharge rates, since we use them in combat robots, which are designed to last 3 minutes (which ends up being 20C continuous discharge rate). If you consider that you want at least 2 minutes of "full throttle" power over the course of a charge of the batteries, the capacity of them must be enough that the maximum current would be 30C, otherwise the batteries would be dead from just the hot rodding. Being that you're driving more than the 2 minutes of full throttle, I'd suspect that any batteries with enough capacity for an hour drive would have enough discharge rate to support what you needed to do.

mmmm electric cars... 10x the range of current cars... thats what... cross country in one charge? can anyone argue with that? Ok fine 10x is not cross country... but it is 2000 miles per f-ing charge!

I'd rather have 200 miles and lighter/cheaper(? at least in terms of environmental costs) batteries.

Just as with gasoline-powered vehicles, I would like to have the choice of many different options.

Well, for energy storage and conversion in gasoline powered cars you only have option. Gasoline stored in a tank and combusted in an Otto cycle engine.

I don't think that people's driving behaviour is divergent enough to support multiple battery chemistries in the long run.

I was thinking I can choose between cars that have different capabilities (small or large, big tank or small, fast or slow) even if the core tech is the same.

In environmental costs, I'd much rather have FeNi chemistry fully explored. Nickel iron batteries can be abused by under and over charging, short circuiting heat, cold, vibration, and other effects and still last decades.

Jay Leno has an antique car that still has a working FeNi battery. I think it needs topped off with distilled water every so often. The electrolyte is KOH so it even acts as a preservative. The only problem with the reaction is it's slow to charge and discharge.

Why is it that people have so many diverse opinions that aren't fully informed when it comes to energy??

It may have one benefit, but 30 seconds on wikipedia informs me that it requires 5 times the mass and 20 times the volume of lithium ion to give equal energy output. Which makes it a complete non starter for anything mobile.

FeNi batteries are a wonderful storage medium for things like solar cell chargers in a house, or a wind turbine setup. I never said this is going to be the next watch battery tech.

And also, the fact is that the first cars were electric: they used various chemistries. And as I said above, Leno has a still working car that uses a NiFe battery: Cheap materials, low maintenance, not heavy metal (and nontoxic to boot).

In fact the original recipe indicated making potash, putting it in distilled water, and filtering out the physical chunks of ash.

Forget electric cars. I'm building an Iron Man suit.

Can you imagine how long it would take to charge a battery that could power a regular sized car for 2000 miles?

Even at 220v/30amps it might take a few days,

Why the downvotes? Shouldn't the capacity of our wires also be a limiting factor?

I would say robotics is another super exciting application, especially humanoid robots.

This would be a real game changer for electric cars. Even a "mere" 3x enhancement would already make them really competitive with combustion engines ones, but with 10x they would just be better than our traditional cars. Let's hope this technology can be industrialized in an economic way.

There's always the whole "we haven't invented a good way to recycle the 20 thousand dollar toxic battery" problem still to deal with.

Cars currently have $50 toxic batteries, in them and yet the recycling rate is near unity for them. If we can manage to recycle something worth $50, surely we can recycle something that is more valuable.

> If we can manage to recycle something worth $50, surely we can recycle something that is more valuable.

That doesn't follow.

Lead-acid car batteries are profitable to recycle because of the chemistry costs, not the unit cost of the battery.

So, what are the costs of recycling these batteries? (Note that the answer is in terms of $/pound.) How does that compare to the cost of using new materials? (Again, the answer is in terms of $/pound.)

Lithium is worth a lot more than lead so unless there is significant reason to think otherwise they are probably worth recycling.

> Lithium is worth a lot

That doesn't tell us anything about the relatve costs of production and recycling lithium that was used in batteries, which happens to be the relevant question.

It'll surely be patented and sat on for a while at a very high price. My bet is we'll need to wait $time_of_release + 10 years until we see things working out over traditional cars.

It will be patented - yes. Sat on at a very high price - I don't think so. Even if you only think about maximizing profits, with a technology like this you would make much more money by creating a new market (mass produced electric cars) with lower margins and very big numbers than with high margins and very little numbers.

On the other hand, if the technology required to mass produce this kind of batteries will be too new, it could take time to scale it and bring costs down. Let's hope it isn't too innovative.

You can't "sit on" patents. The whole point of the patent system is to get an idea out there so people can use it. As a patent holder you're required to license your invention for a reasonable amount (I'm not really sure how that's determined - probably in court). If you don't, a judge can put your invention in the public domain and give you nothing.

The stories you hear about the 300 mpg carburetor and machines that produce power from the spin of electrons? These devices, if they actually existed, would have to be bought and hidden away without ever entering the patent system. And the buyer (oil companies, is it?) would have to take the chance somebody else would patent the invention for which he paid millions.

Citation, please. I've never heard of compulsory licensing occurring in the US outside of government contracts and anti-trust settlements.

For the record, there are a lot of experimental battery technologies out there:

http://en.wikipedia.org/wiki/Lithium-ion_battery#Variations_...

http://en.wikipedia.org/wiki/Lithium-sulfur_battery

http://en.wikipedia.org/wiki/Nanowire_battery

Just... one of these will probably catch on, yes, and that's awesome, but we've come up with so many different ideas that at this point, demonstrating a high-capacity lithium battery prototype is the Aristocrats joke of battery science.

And the promised capacity increase is always 10x, neither more nor less.

Lithium-sulfur is an older, more well-studied technique, and it only promises a 4x increase. There are still quite a few kinks to be worked out but I think it has the best potential of the bunch for the near future.

Here's the press release from Northwestern University:

http://www.northwestern.edu/newscenter/stories/2011/11/batte...

and the associated journal paper, published in Advanced Energy Materials:

http://onlinelibrary.wiley.com/doi/10.1002/aenm.201100426/ab...

Is there anything graphene can't do?

So far: make it to market. But we're optimistic.

While this could change the game for electric cars (Edit: as others have already been discussing), it would also be an amazing advance for cell phones and computers. Imagine a cell phone that had a lighter battery but still lasted through a week of use between charges. Or an incredibly thin and light battery (and a correspondingly thin and light phone) that still lasted a couple of days.

Or a notebook that didn't need all the power management to dial down the CPU and GPU when unplugged, and could barrel away full speed and still last for a day or two. You'd still have to worry about heat dissipation, but there are plenty of fast notebooks that handle that fine when plugged in.

Or an iPad with the battery life of a Kindle. Or a Kindle that you charged once a year.

But can you imagine trying to find the charging cable for your Kindle after a year?

If they keep it to a standard mini-USB cable, it won't be too bad.

Bah, at that rate you could just buy a new kindle ;)

For a notebook you still want to reduce energy usage. All that heat has to go somewhere and a hot device and loud fan are very annoying.

Apart from that, I agree. Any of this new battery types will first be used in small, high priced devices.

Or they can reduce the size of the batteries to cut weight.

So how long do you reckon we will have to wait for something like this? I'm still waiting for lithium-air batteries from MIT http://web.mit.edu/newsoffice/2011/better-battery-storage-07...

Patience. It's usually a minimum of 5 years for tech to go from the lab to commercial use, and often 10 years before it's in common use. Furthermore since there are probably dozens of competing technologies currently in the lab for energy storage, most of them won't ever make mainstream commercial use.

Still waiting? It takes longer than four months to bring new technology from research to market. Put up some money for investing in manufacturing and maybe your complaint would be valid.

So now the battery in my laptop will have 10x the energy in it when it explodes. It will be even more like carrying a bomb around with you.

not mentioned in the article, but this could be a huge help for electric cars, and to the solar power industry.

What is the safety of this battery? At 10x power we are looking at potential explosion for eletric cars instead of raging fire for gas cars... Does it work in 30 below zero?

As just a lay commenter on ycombinator, I can point out that they're just changing the anode atomic structure. They're not changing the Lithium salt.

So your concerns about safety are fine - this should only be as safe as any other Lithium-ion or Lithium-polymer battery.

>this should only be as safe as any other Lithium-ion or Lithium-polymer battery.

So, they will explode fairly often then.

Why do you assume it's not as safe as gas? Gas has a similar energy/m3 profile.

And not everyone cares whether it works at thirty below. Most places don't get that cold.

From a symposium on Graphene at Mcgill earlier this year. One study presented was Graphene/Metal contact

http://www.physics.mcgill.ca/~maassenj/aps/2011-March-meetin...

I still don't understand why people think this will do anything for electric cars. The bottleneck is how long it takes to charge your car. If you have a 60KW/hr pack, you can only charge it so fast with a 110v/20amp jack (for the sake of pie in the sky projections assume 50% charging efficiency between charger and battery). Period the end. you could always do 220v/30amps, or 208v/30amps/3phase. or 440v/1000amps. the tradeoff is in how many idiots electrocute themselves. It never ceases to amaze me how people don't get this simple simple fact. It's like saying that you can fill up a swimming pool faster because you've made a sturdier garden hose.

That's pretty short-sighted Mike. First, a 10x battery boost would mean you don't have to recharge the car fully over a week.

This is also a boon for battery swapping stations which are bein built in Israel and other places.

lol. it's like you're trying to troll me. #5,612,606.

He's talking about this patent, by the way, which I know he made: http://www.patents.com/us-5612606.html

But that patent's going to be expired by the time these batteries are ready.

Shai Agassi's patent #7,993,155 for a charging connector even references this one. Doesn't look like they consider it a problem.

well i'm also talking about how the battery swap stations being built in israel and other places, are being built by Better Place. Which in turn was started by Shai Agassi, who was never approached by my former company about being an investor in this technology. and consequently has to operate outside of zones that issue/respect patents.

Most homes have 220v devices that people use safely every day without electrocuting themselves. If your really concerned about how fast they charge just run a second line and wow it's charging twice as fast. On top of that decent charging stations are well over 90% efficient much worse than that and they start dumping a lot of heat which harms the battery. 3 * 220v/50amps * 90% efficiency will fill that 60KW/hr pack right quick.

So sure, it takes a long time to fill the tank using a normal extension cord, but then again most people can't refill their gas powered car at home so it's still a net win.

You don't say? they have washing machines that they plug and unplug every single day? 2 lines, why didn't I think of that. Brilliant! It's so cheap to build a 3-phase charger at 400V at 32 amps so you can charge a 20kWh pack in 2 hours (60kWh in 6!). Everyone should do it. It makes perfect economic sense! It's exactly like gas. Everytime I want to fill up my car, I sit at the pump for 6 hours. But this battery tech will change all that. Yes, now that we have better longer-lasting batteries, it won't take so long to fill up. Nevermind that there is an ENORMOUS demand for batteries, that these are at least a decade away from production, and thusly economies of scale are already reached. But sure, continue to tell me the same old bullshit. eventually someone will believe it, and we'll all start living in the future.

I guess the reason that the US thinks that 220V is unsafe is the plug socket design?

Could you adopt a new plug for existing 220V appliances (AIUI you have 220v for washing machines & dryers etc?). Then over time you could migrate all your plugs to the new sockets and voilá - the whole world gets to boil a kettle in a reasonable amount of time.

Would still take 7 hours to charge your 20kWh car battery, natch.

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