Scientists Deliver a Longer-Lasting Lithium-Oxygen Battery (technologyreview.com) 82
Packing more energy into batteries is the key to delivering electric cars with longer range, smartphones that can last days -- and cheaper electronic products all around. Lithium-oxygen batteries represent one of the more promising paths toward that end. From a report: They could boost energy density by an order of magnitude above conventional lithium-ion batteries -- in theory, at least. In a paper published this week in Science journal, researchers at the University of Waterloo identified ways of addressing some of the major hurdles to converting that potential into commercial reality.
A critical problem has been that as a lithium-oxygen battery discharges, oxygen is converted into superoxide and then lithium peroxide, reactive compounds that corrode the battery's components over time. That, in turn, limits its recharging ability -- and any real-world utility. To get around the problem, researchers switched from a carbon cathode to one made of nickel oxide and supported by a stainless steel mesh. They also used molten salt for the electrolyte -- the part of the battery that allows positively charged ions to move between the electrodes -- and raised the battery's operating temperature to 150C. Those steps made it possible to achieve about three times the number of charging cycles as earlier lithium-oxygen efforts. The researchers also managed to increase the energy per unit of mass by more than 50 percent.
A critical problem has been that as a lithium-oxygen battery discharges, oxygen is converted into superoxide and then lithium peroxide, reactive compounds that corrode the battery's components over time. That, in turn, limits its recharging ability -- and any real-world utility. To get around the problem, researchers switched from a carbon cathode to one made of nickel oxide and supported by a stainless steel mesh. They also used molten salt for the electrolyte -- the part of the battery that allows positively charged ions to move between the electrodes -- and raised the battery's operating temperature to 150C. Those steps made it possible to achieve about three times the number of charging cycles as earlier lithium-oxygen efforts. The researchers also managed to increase the energy per unit of mass by more than 50 percent.
Bonus feature! (Score:2)
You can now also heat your house with it while discharging!
Re: (Score:1)
Re:Bogus feature! (Score:2)
Narcocide observed:
You can now also heat your house with it while discharging!
If your house is a materials lab, that is.
The headline is (surprise!) profoundly - and purposefully - misleading. These researchers delivered nothing more than a benchtop demonstration. In other words, a glorified science fair project.
Perhaps it's just me, but to use the word "deliver" accurately to describe what these folks have built, it would have to be, at a minimum, a working commercial prototype, designed for mass manufacture. The demo here is a long damned way from that ...
Have I seen this before? (Score:3, Insightful)
I have this sneaking suspicious that news about battery improvements is a circle of different press releases, such that they re-publish the same article every five years or so before moving further around the circle.
The whole stainless steel mesh thing sounds just familiar enough I'm pretty sure they gave the game away.
Oh battery scientists, you are so clever! They are probably all laughing at us from a tropical shore, drinks in hand and diesel generators happily powering a boombox.
Re: (Score:2)
No, I think he's actually right this time. Within the last few years I remember hearing separately about both the "lithium-oxygen" thing and the "[something unexpected] mesh cathode" thing. Long enough ago in both cases that it's suspicious this is being reported on again as though it's brand new now. Who knows though, maybe they did really have another breakthrough in feasibility? I didn't read the article.
Re: (Score:3)
Don't think so, I'd definitely remember hearing about a battery with a higher operating temperature than an internal combustion engine!
Improving energy density by an entire order... (Score:2)
Existing EV's can be fast charged to nearly completely charged in about a half hour.... would that mean that even overnight charging would have to be "fast"?
Re:Improving energy density by an entire order... (Score:4, Insightful)
Re: (Score:2)
Re: Improving energy density by an entire order... (Score:1)
Yup - I'm not changing. My horse is working great.
Re:Improving energy density by an entire order... (Score:4, Insightful)
Well yeah, if you want to charge from empty to full overnight you would have to fast charge. But that would not usually be the case, would it? If you have 10x the energy, thus 10x the range, you could go 2500 miles on a charge. Nobody is doing that daily. So slow charge to 10% the first night, use half of that charge during the day, after the next night you are at 15%. In 20 days you will be at 100%, then you just need to keep it 'topped up'.
Re: (Score:2, Insightful)
Or, thinking like a manufacturer, put 1/8th the amount of batteries in the vehicle.
Re: (Score:2)
Sure if this is a commuter car. Those of us who travel distance on a regular basis need "typical" range with a "reasonable" recharge time.. Most manufacturers consider 300 miles "typical" then I can fill my gas tank in 15 minutes.. I would consider a longer amount of time reasonable but there's a limit.. probably a half hour and honestly that's longer than I'd like.
Now if they can increase my range in the orders being discussed so I could go 1000 miles / charge or more then I'd tolerate a MUCH longer charg
Re: (Score:2)
If it can fast charge to 50%, then you can get 150 miles per half hour charge up to 1500 miles, seems nice.
I'm more interested in being able to do 600 miles in a reasonable at home 12 hour charge though.
I'd be willing to bet they use 3 times the storage for 1/3 the battery size, and allow 50% for leveling/marking dead cells.
This would allow for double the fast charge range.
Re: (Score:2)
Or alternate between several packs to extend life, and allow the user to charge up as needed. Recommend that the user keep it above 500 miles and below 1,000 miles, and change which packs are charged and which ones aren't. Periodically move charge around as needed to keep cells from getting too low.
Doesn't necessarily change charging time. (Score:2)
Going by other lithium cells, batteries charging currents are generally a function of the capacity of the battery which means that fast charging time generally remains constant. So, if a battery has 10x the capacity of a base battery, the charging current will be on the order of 10x with the overall charging time being the same.
Of course, the circuitry for handling 10x the current is going to be significantly different than the base battery.
Re: (Score:3)
Providing 1,200 kW (ten Tesla superchargers) over any sort of human-manipulatable cable would likely be infeasible. You'd either have to use an insane voltage, requiring even thicker jackets to reduce the safety risk, or use an insane amperage, resulting in a conductor diameter measured in inches. And imagine each charge station drawing as much power as the entire supercharger does now. The existing electrical infrastructure probably can't provide that much power in most places.
Realistically, if we got a
Re: (Score:2)
Re: (Score:2)
Ceramic superconductors would likely shatter if you bend them like you would a charge cord. Also, they are way too heavy. I'm not sure about the old-style metallic superconductors, but even those are significantly less flexible than wire at normal temperatures, as I understand it. So either way, you're replacing one flexibility problem with another, I think.
There are some experimental superconductors in development that might make what you're suggesting possible, but I doubt they are anywhere near being
Re:Improving energy density by an entire order... (Score:5, Insightful)
Why would a car manufacturer keep a battery of the same size with 10x the density, knowing that charging that battery would be a problem?
They could always just make a battery pack that gives X range, and keep the charging the same for the value of X, but with a much smaller pack (less mass)
Re: (Score:2)
Re: (Score:2)
knowing that charging that battery would be a problem?
Why is charging the battery a problem? You are talking about a function of time. Just because a person can only charge 1/10th of that amount over night doesn't mean they don't have benefits from the battery. After all, who actually drives 250 miles every day anyway.
Re: (Score:3)
Not necessarily. Battery charging rate depends on a number of things, including limits on charging rate to maximize battery life.
Tesla's supercharging stations use proprietary systems to deliver "up to" 120KWs to the car. At that rate it should completely charge a completely discharged 90 kWh battery in 45 minutes. But I don't think this happens, because to preserve the battery rate of energy deliver drops as you get closer to topped up. Given that's the case, shoving 90kWh of energy into a 180 kWh ba
Re: (Score:2)
My favorite in-pants thing!
Right. Because hot-grits batteries are just not panning out the way we all hoped.
[Why do I suddenly think of "Natalie Portman" and "discharge"? :-/]
Your phone lasts for days... (Score:3, Insightful)
Because with a 150C battery in it, you don't dare pick it up to use it.
Re:Your phone lasts for days... (Score:5, Funny)
Because with a 150C battery in it, you don't dare pick it up to use it.
Meh. That's Prior Art for Samsung.
Oh Come On (Score:5, Insightful)
It's another basic science press release! A molten salt battery, Yet somehow it runs at 150C, so salt doesn't mean NaCl, which melts at 801 degrees centegrade. And it's corrosive and eats itself. OK, lead-acid batteries are too, but there's some significant technology to get past, and this is still just a research project. Also, I'm wondering what heating up the whole battery to 150 C to start your car will look like, and what sort of battery you will need to do that. Obviously not the same battery.
Wake me up when I can buy one off the shelf, OK?
Re: (Score:2)
"Yet somehow it runs at 150C, so salt doesn't mean NaCl, which melts at 801 degrees centegrade."
So it's the temperature that tipped you off that they weren't referring to table salt? You have quite an intellect, Bruce.
Yet somehow it runs at 150C! What is this, a school for ants?!?
Re: (Score:2)
Re: (Score:2)
Sure I did. They were in that movie with Olivia Newton-John. :-)
You mean like this [greasecar.com]. It uses both refined diesel fuel and unrefined cooking grease, with the diesel to run the car and make heat until the waste heat from the engine makes the cooking grease hot enough to get through fuel injectors, etc. Some filtering is necessary too.
I also know the director of Freeway Philharmonic [freewayphil.com], which has a scene of poor orchestra musicians syphoning cooking oil to run their car, not necessari
Re: (Score:2)
I see these BS science press releases near daily. If 1 millionth of them came true, we'
Re: (Score:2)
Re: (Score:3)
Re: (Score:2)
Yet somehow it runs at 150C, so salt doesn't mean NaCl, which melts at 801 degrees centegrade.
This is surprising? Molten salt batteries are old tech and are capable of delivering very high power output due to the very high ionic mobility. And no one every meant molten sodium chloride by a molten salt battery. Ever.
Wake me up when I can buy one off the shelf, OK?
Wakey wakey!
https://energyconnections.net.... [energyconnections.net.au]
Looks like they're even in stock.
Re: (Score:2)
Re: (Score:2)
I'm assuming that's sarcasm, but just in case it's not -- internal combustion engines run about equally hot.
Results depend on source (Score:3)
We've found that batteries made for the Chinese internal market frequently have a lower capacity than those made for the Korean and US markets. Has to do with how they're made. Be aware of this.
That said, also be aware of the operating ranges and any physical defects.
actual, real improvements yet ? (Score:2)
I know science is hard, but it's astounding how many "new and improved battery" stories that we see, and how few of them end up being useful.
it would be really interesting to do some statistics and see how many of these things have actually resulted in improvements to batteries that you can actually buy.
my guess is that he number is really low, maybe even 0.
it's kind of a amazing.
Re: (Score:3)
Re: (Score:2)
I know science is hard, but it's astounding how many "new and improved battery" stories that we see, and how few of them end up being useful.
On the other hand have you seen hoe uch batteries have improved in the last 20 years? Compare your old Ni-Cd drill with a odern Li-Ion one, for example. No contest.
What glove material to use (Score:1)
... when you are not allowed to use asbestos for your glowing phone at 150C?
FTA: 15 years away (Score:1)
Its always 10-15 years away...
Scientists deliver ... (Score:2)
Wake me when the title says:
delivers ...
They didn't deliver anything? (Score:2)
Can't read the paper and the abstract is ambiguous so it seems like the paper is about a 'way ahead' as opposed to an actual device prototype. It seemed like the paper + article were a way to profile the research in order to get funding to actually build something ... a long long way (as one of the researchers says herself) from actually having a product or even it seems an experimental prototype.