IIT, Argonne team designs Li2O-based Li-air battery with solid electrolyte; four-electron reaction for higher energy density
25 February 2023
Researchers at the Illinois Institute of Technology (IIT) and US Department of Energy’s (DOE) Argonne National Laboratory have developed a lithium-air battery with a solid electrolyte. The battery is rechargeable for 1000 cycles with a low polarization gap and can operate at high rates. A paper on their work is published in the journal Science.
The team’s battery chemistry with the solid electrolyte can potentially boost the energy density by as much as four times above lithium-ion batteries, which translates into longer driving range.
A lithium-air battery based on lithium oxide (Li2O) formation can theoretically deliver an energy density that is comparable to that of gasoline. Lithium oxide formation involves a four-electron reaction that is more difficult to achieve than the one- and two-electron reaction processes that result in lithium superoxide (LiO2) and lithium peroxide (Li2O2), respectively.
By using a composite polymer electrolyte based on Li10GeP2S12 nanoparticles embedded in a modified polyethylene oxide polymer matrix, we found that Li2O is the main product in a room temperature solid-state lithium-air battery. … The four-electron reaction is enabled by a mixed ion–electron-conducting discharge product and its interface with air.
—Kondori et al.
In past lithium-air designs, the lithium in a lithium metal anode moves through a liquid electrolyte to combine with oxygen during the discharge, yielding lithium peroxide (Li2O2) or superoxide (LiO2) at the cathode. The lithium peroxide or superoxide is then broken back down into its lithium and oxygen components during the charge. This chemical sequence stores and releases energy on demand.
Schematic shows lithium-air battery cell consisting of lithium metal anode, air-based cathode, and solid ceramic polymer electrolyte (CPE). On discharge and charge, lithium ions (Li+) go from anode to cathode, then back. (Image by Argonne National Laboratory.)
The team’s new solid electrolyte is composed of a ceramic polymer material made from relatively inexpensive elements in nanoparticle form. This new solid enables chemical reactions that produce lithium oxide (Li2O) on discharge.
The chemical reaction for lithium superoxide or peroxide only involves one or two electrons stored per oxygen molecule, whereas that for lithium oxide involves four electrons.
—co-author Rachid Amine
More electrons stored means higher energy density.
The team’s lithium-air design is the first lithium-air battery that has achieved a four-electron reaction at room temperature. It also operates with oxygen supplied by air from the surrounding environment. The capability to run with air avoids the need for oxygen tanks to operate, a problem with earlier designs.
For over a decade, scientists at Argonne and elsewhere have been working overtime to develop a lithium battery that makes use of the oxygen in air. The lithium-air battery has the highest projected energy density of any battery technology being considered for the next generation of batteries beyond lithium-ion.
—Larry Curtiss, an Argonne Distinguished Fellow and co-corresponding author
The team employed many different techniques to establish that a four-electron reaction was actually taking place. One key technique was transmission electron microscopy (TEM) of the discharge products on the cathode surface, which was carried out at Argonne’s Center for Nanoscale Materials, a DOE Office of Science user facility. The TEM images provided valuable insight into the four-electron discharge mechanism.
Past lithium-air test cells suffered from very short cycle lives. The team established that this shortcoming is not the case for their new battery design by building and operating a test cell for 1000 cycles, demonstrating its stability over repeated charge and discharge.
With further development, we expect our new design for the lithium-air battery to also reach a record energy density of 1200 watt-hours per kilogram. That is nearly four times better than lithium-ion batteries.
—Larry Curtiss
The research was funded by the DOE Vehicle Technologies Office and the Office of Basic Energy Sciences through the Joint Center for Energy Storage Research.
Resources
Alireza Kondori, Ahmad Mosen Harzandi, Rachid Amine, Mahmoud Tamadoni Saray, Lei Yu, Tongchao Liu, Jianguo Wen, Nannan Shan, Hsien-Hau Wang, Anh T. Ngo, Paul C. Redfern, Christopher S. Johnson, Khalil Amine, Reza Shahbazian-Yassar, Mohammad Asadi, Larry A. Curtiss, Mohammadreza Esmaeilirad (2023) “A room temperature rechargeable Li2O-based lithium-air battery enabled by a solid electrolyte” Science doi: 10.1126/science.abq1347
A cracking, impressive result hitting 1000 cycles!
Recently @sd highlighted the 'weight problem' of lithium air:
https://www.greencarcongress.com/2023/02/20230223-solithor.html
' ' a lithium air battery that starts with 1000 lbs of lithium, you end up with 3667 lbs of lithium oxide (6 + 16 = 22 and 22/6 = 3.667). Possible for trucks but a real problem for aircraft. '
From the figures given I am trying to work out what the actual weight increase for the total battery is, since obviously only part of it is lithium, which will become lithium oxide.
Since we know that the total energy density is 1200Wh/kg, it should be possible to calculate the weight of the lithium.
Unfortunately at the moment all that I am getting by googling is the energy density of lithium ion batteries, not the potential energy per kg of lithium when combined with air.
In between the football today I will continue to poke around, but since I am primarily famous for my great beauty rather than my intelligence, if someone can come up with the calculations, that would be very informative.
Especially for aeroplanes, what total weight do you end up with for the battery pack after discharge when the lithium part has become lithium oxide?
Not 3.667 times, clearly, but a fairly substantial increase just the same
Posted by: Davemart | 25 February 2023 at 01:38 AM
I haven't managed to get rid of info which bundles in the rest of the components of a lithium air battery, but I have dug out the theoretical density of a lithium air battery:
' At a nominal potential of about 3 V, the theoretical specific energy for a lithium/air battery is over 5000 Wh kg−1 for the reaction forming lithium hydroxide (LiOH) (Li+1/4 O2+1/2 H2O=LiOH) and 11 000 Wh kg−1 for the reaction forming lithium peroxide (Li2O2) (Li+O2=Li2O2) or for the reaction of lithium with dissolved oxygen in seawater, rivaling the energy density for hydrocarbon fuel cells and far exceeding Li-ion battery chemistry that has a theoretical specific energy of about 400 Wh kg−1'
https://www.sciencedirect.com/science/article/pii/B9780444527455001842
Taking the figure for lithium peroxide formation, which seems to be the apposite one and the reaction @sd is referring to, then since the limit is the amount of lithium then 1200Wh/kg/11,000Wh/kg is of the order of a tenth of the weight of the battery being pure lithium when fully charged.
So taking @sd's figure of 3.667 times the weight when discharged, we come out to an increase in total battery weight of perhaps a third when fully discharged.
That is annoying when landing an aircraft, since with gasolene fuel burn an aircraft is now lighter when landing, but sounds very manageable.
Posted by: Davemart | 25 February 2023 at 01:58 AM
One of the hassles with solid state has been power output, as the solid electrolyte can make them sluggish.
Unfortunately without buying the article all they say is that it can operate ' at a high rate'
It would be informative to know how high, and for how long.
Posted by: Davemart | 25 February 2023 at 02:01 AM
Typically the energy density reckoned needed to be really useful for aircraft is of the order of 600-800Wh/kg
Even using the figures for the battery in a discharged state, this looks like it would hit or beat that, so enormous potential.
We still won't be flying transatlantic in a battery powered plane, but for regional even with fairly substantial aircraft it is hopeful that this could do the job.
Posted by: Davemart | 25 February 2023 at 02:14 AM
And of course great for cars, trucks etc!
Posted by: Davemart | 25 February 2023 at 02:16 AM
A substantial analysis of lithium air batteries here:
https://www.electronicsforu.com/technology-trends/lithium-air-batteries-replace-lithium-ion-batteries-in-evs
Of note regarding Argonne's use of a ceramic polymer separator:
' Ceramic electrolytes like LAGP/LATP have been closer to commercial applications. However, several crucial issues still remain as obstacles to their practical application. Although the lithium-ion conductivity of the ceramic electrolyte is quite high and the interfacial impedance between the particles in the ceramic sheet can be minimised, the interface contact and interface compatibility of the ceramic and the electrode are challenging.
It is well known that achieving intimate solid-to-solid contact is extremely vital but also extremely difficult to achieve. Poor solid-to-solid contact commonly results in high interface resistance and the formation of lithium dendrites. In addition, it is very difficult for ceramic sheets to be defect-free, which also results in dendrite formation. Therefore, resolving interface issues is critical for the performance of ceramic electrolyte.
For better physical contact, introducing an alloy layer between the electrolyte and lithium metal or depositing the electrolyte material and the cathode material together are effective. The combination of ceramic electrolyte and polymer electrolyte is also a method to improve the interface engineering. Polymers are more liquid-like than ceramics and solid-liquid contact has inherent advantages over solid-solid contact. However, as the ionic conductivity of polymer electrolyte is lower than ceramic, it is important to find a balance point between the ratio of these two components.'
Some of the other issues mentioned include difficulties in adequately filtering the air to exclude moisture and other contaminents, which they specifically mention in a mobile setting, and dendrite formation, which has presumably been adequately dealt with by Argonne since they have hit 1,000 cycles.
Very, very hopeful stuff, but I don't expect them in cars by Thursday week! ;-)
Posted by: Davemart | 25 February 2023 at 02:46 AM
The ability to use batteries instead of fuel cells/ jet engines using hydrogen or SAF in a wider range of longer distance, heavier air transport also eliminates the remaining issue of contrails.
Posted by: Davemart | 25 February 2023 at 02:57 AM
https://www.transparencymarketresearch.com/lithium-air-batteries-market.html
They reckon here that the total chemical costs of lithium air batteries is 1/30th that of lithium ion, which is not only handy in itself but must indicate that little or no rare or scarce elements are needed.
I would like to see more specific info on the Argonne battery constituents.
Assembly is also another issue, as the study I linked above on lithium air indicated that the separator can perhaps be tricky.
Posted by: Davemart | 25 February 2023 at 03:54 AM
Here is where I have messed up.
I used the potential energy of lithium peroxide for the 11,000Wh/kg (Li2O2)
What this Argonne fuel cell discharges to is lithium oxide (L2O)
I don't at the moment have figures for the theoretical energy output of that reaction.
Here is an article, way above my head in the realms of electrochemistry, outlining the oxidisation of lithium:
https://chemistry.stackexchange.com/questions/38060/understanding-the-energy-produced-from-oxidizing-1-kg-of-lithium
In the initial questio he also uses 11,000Wh/kg, although why is not clear to me.
If that is right, I may have accidentally arrived at the right answer using the wrong methodology
Posted by: Davemart | 25 February 2023 at 05:18 AM
Mentioned here is the propensity of lithium to also react with nitrogen in the air:
https://www.chemguide.co.uk/inorganic/group1/reacto2.html
How that is prevented or to be prevented in the Argonne cell is not clear, or how complicated such isolation would be.
Posted by: Davemart | 25 February 2023 at 05:21 AM
' By storing O2 as lithium oxide (Li2O) instead of lithium peroxide (Li2O2), the battery not only maintained excellent charging characteristics, it achieved the maximum four-electron transfer in the system, thereby increasing the theoretical energy storage by 50 per cent.'
https://www.sciencedaily.com/releases/2018/08/180823143913.htm
So it looks as though I am safe, indeed somewhat conservative, in using the figures for the theoretical energy output of lithium peroxide.
I am going to go for a SWAG of 25% weight increase for the battery to fully discharged.
Of course, I may have totally got my calculations wrong and made erroneous assumptions!
Posted by: Davemart | 25 February 2023 at 05:58 AM
Using these on a plane presents an interesting problem never before encountered in 120 years of powered flight: the plane will land considerably heavier than when it took off!
I look at the car question as one of a 500 kg budget to move a reasonably large vehicle 300 miles between refills. Gasoline also has 1.2 kWh/kg energy density, but it has a sunk "cost" of ~350 kg of engine/transmission and some more for damping NVH, which even a very good engine uses 60% of the fuel to generate . A 200 hp electric motor/transmission (with way less NVH) is more on lines of 100 kg. So taking a conservative 3 miles/kWh, 100 kg of battery, even if it swells to 380 kg leaves you within the weight budget.
Posted by: Albert E Short | 25 February 2023 at 03:51 PM
Contain your enthusiasm guys. This lab toy uses a Germanium based separator.
Germanium : ~$2000 / kg.
Just another exotic lab battery. Nice to see, but we will not be using it any time soon.
Posted by: peskanov | 26 February 2023 at 12:19 AM
@Albert E Short
I think a decimal point has misbehaved for you! ;-)
I have gasoline here at 12.7kWh/kg, not 1.2KWh/kg:
https://hypertextbook.com/facts/2003/ArthurGolnik.shtml
Posted by: Davemart | 26 February 2023 at 12:26 AM
Hi peskanov:
I thought this sort of battery does not need a separator other than the electrolyte?
' In an SSB, there is no need for a separator, since the solid electrolyte acts as a physical barrier between the anode and cathode. The electrolyte is typically made of sulfide, ceramic, or polymer material. They all have shortcomings—some solids are unstable in the presence of air, while others are brittle and can crack—but companies say they have fixes in place.'
https://cen.acs.org/energy/energy-storage-/solid-opportunity-lithium-ion-batteries/99/i32
Are we talking about the same battery tech, or perhaps two different ones, as Argonne will be looking into more than one type?
Posted by: Davemart | 26 February 2023 at 12:42 AM
@Davemart - you are correct, I had a confirmation bias incident where the article said 'similar energy density to gasoline'; so when I saw 12200 as the kWh/kg I subconsciously dropped the zero and went with it. Later in the bar, I thought that can't be right since I knew ~ 35 KWh/gallon was the density of gasoline but you had already caught it.
In any case, the point stands that even that gaudy order-of-magnitude-higher energy density of gasoline vs this advanced battery is not all that relevant in the weight budget of a reasonably sized car going 300 miles between fill-ups.
Posted by: Albert E Short | 26 February 2023 at 08:17 AM
@Albert E Short:
The kind of energy density this has if it pans out otherwise will mean that there is no issue at all about weight for BEVs, which is why I focussed on aerospace to see how it might do in that more demanding application.
This would deal conclusively with my whinge about fat and heavy!
I have always felt that it was important to keep the focus on light and cheap for cars, and my issue with BEVs has been that it was unclear when or even possibly whether the batteries usually assumed would arrive.
To further clarify I have never advocated fuel cell cars at current costs either, especially since they come into their own for larger vehicles, and the last thing we need is umpteen million SUVs.
Hopefully this one may, may, have cracked it, assuming that @peskanov is mistaken, and his stricture on germanium separators applies to batteries with liquid electrolytes, not the solid ones this uses.
We will need to keep an eye on this for gotcha's though, with dealing with moisture, lithium nitrides and whatever 'high' charge rates mean, as well as possible manufacturing hassles.
So in my view we are not home and hosed yet, but so far, so good.
Posted by: Davemart | 26 February 2023 at 09:00 AM
This is an exciting development. Given the talent, resources and time expended in pursuit of progress in the area at Argonne, not surprising they would ultimately achieve this kind of breakthrough. Bravo to Kondori, Amine at al for their determination and perseverance.
Given the theoretical capacity of the materials, methodical modern scientific methods of discovery (molecular simulation, visualization like TEM described above) and the substantial financial resources applied to this research as a national imperative, it has seemed to me to be an inevitable outcome. No doubt it is a milestone on a path that will continue indefinitely until the next inflection point with an entirely different technology.
Ever since BEVs established their dominance as the successor to petroleum, the financial incentives became so big that continued research and development of high energy batteries are a certainty.
At some point well before 100% ZEV mandates take effect, the demand for ICE cars will begin a steep decline because their resale value will diminish rapidly. Who will want an ICE if you can purchase a 1,000 mile BEV that needs to be charged only once a month? (Or a cheaper 500 mile BEV that can be charged once every two weeks, etc, etc).
Many parking lots have solar canopies now, it seems like that will be de rigueur soon. The price of solar fuel will find its floor soon enough.
The OEM laggards will have a much more difficult time managing the transition.
Posted by: electric-car-insider.com | 26 February 2023 at 01:11 PM
@Davemart,
yes, you are correct. This is solid state (not semisolid) and does not use a separator.
When thinking on this type of battery, my mind drifts to the Quantumscape battery, which has an exotic separator.
In this Li-air battery, Germanium is found in the electrolyte (Li-Ge-P-S).
Posted by: peskanov | 26 February 2023 at 02:01 PM
@electric car insider:
When I hear of the 'inevitable triumph' of this or that, I get quite nostalgic for the inevitable triumph of communism.....
I don't believe in superhuman certainty de haut en bas.
But if this can make it to economic mass production, and at the moment we are on a few cells on a workbase position which in the case of li-on took many years to reach substantial production, then I am as enthusiastic as anyone, having for instance argued vigorously in favour of the Nissan Leaf when it was introduced.
I think this is likely to be way quicker, but there are never, never guarantees.
Posted by: Davemart | 27 February 2023 at 12:10 AM
Hi peskanov
Easily done. A slight misreading can cause all sorts of problems.
I would be grateful if you or sd or someone would check my calculations to make sure I am in the ballpark for weight gain after discharge, as I have no technical background to give me any confidence and it is easy to screw up.
I will revise my earlier 25% as I try to be conservative, and although 'gubbins' tend to add to the weight of a battery, which is why I went that way as it would decrease the weight gain, for the purpose of this calculation it is safer to not allow for that imponderble.
So I am going to go for around 30% as the weight gain to full discharge, to be on the safe side.
Have I screwed up, or do you guys with a better technical background concur?
Posted by: Davemart | 27 February 2023 at 12:19 AM
To ask the question another way:
I am not sure that aside from possible errors in calculation, whether my methodology of trying to determine the theoretical energy of the lithium to L2O reaction and taking that as showing the weight of the lithium which then puts on weight in its conversion to L2O is as sound as it appears, or if other factors I have not thought of come into play. so for instance perhaps as the amount of Li converted to LiO2 increases, then the reaction gradually decreases, so in practise the effecgtive amount of lithium for conversion is less than theoretical, hence the weight increase would be less.
Hey, guys, I am punching way above my weight here!
Help!
Posted by: Davemart | 27 February 2023 at 01:14 AM
@Davemart,
I have tried in the past to make this kind of calculations (I have a copy of the TAB battery book at hand), but I found it not to be very useful. Even if you make the correct calculation, the battery always need an excess of the ion carrying element (lithium) in order to work correctly, and I know no way to estimate that.
Also, at the end what I am interested in is the whole cell energy density; as every type of cell contains a lot of inactive materials (like binders, current collectors, packaging...) I prefer to just take a look at the papers (which always show "best case" numbers and must be taken with a pinch of salt).
So in short, no, I can't help you with that lithium estimation; sorry.
Posted by: peskanov | 27 February 2023 at 04:33 AM
@peskanov
Just so.
Unless I have got totally confused though, which is always possible and what I am trying to check, then a higher amount of lithium, unused, would mean that the total weight increase of the pack would be lower, not higher.
So kicking on from @sd's interesting comment that lithium air batteries have an increase on discharge:
' ' a lithium air battery that starts with 1000 lbs of lithium, you end up with 3667 lbs of lithium oxide (6 + 16 = 22 and 22/6 = 3.667). Possible for trucks but a real problem for aircraft. '
At the pack level I am suggesting that the overall increase in weight is around 30%, if that.
Which is pretty manageable, compared at least to what looks on the face of it like a prohibitative 3.667 factor.
We are told that this tech should be able to manage 1200Wh/kg, which even allowing for such an increase in weight on discharge and also for deterioration over 1,000 cycles down to presumably the standard 80% capacity stays well within the envelope for substantial flight capability.
And of course is several times better than current lithium ion batteries.
Posted by: Davemart | 27 February 2023 at 04:50 AM
When I first saw that oxidizing a kilogram of lithium had approximately the same energy potential oxidizing a kilogram of gasoline or JetA, I thought that it would be possible to build battery electric transcontinental or trans-pacific aircraft Even if you did not achieve the full electric potential, the efficiency difference between the electric motors and jet engine might still make it possible. However, the problem is that air type batteries gain weight because now you are picking up the weight of the oxygen.
I do believe that we will have battery electric aircraft especially if the lithium sulfur batteries work out. Lyten is claiming that they will have 900 Whr/kg but it is not lost on me that Oxis also had high claims and went bankrupt. 900 Whr/kg should be good enough for regional jet type planes with 1000 to 1500 km range but it will not get you across the ocean. Hydrogen could be made to work but might not be economical compared to the so-called SAF (Sustainable Aviation Fuel). Maybe ammonia would work and has the advantage that there is no CO2 produced.
One crazy thought that I had is that lithium air might be useful for so-called Kamikaze drones as you do not need to keep the lithium oxide for reuse.
Anyway, I think that this research work on rechargeable lithium air looks promising but I expect that the next big step in batteries will be lithium sulfur. It takes a while to go from research to production.
Posted by: sd | 28 February 2023 at 07:47 PM