Related: https://manifold.markets/MikhailTal/donut-battery-is-essentially-lithiu

Also took me sometime to get that the guy who is talking in the lab with the 🦺 is actually the cto and cofounder of Donut labs not somebody from VTT (it was clearly labeled in the video, still I didn't get it, while watching the explanation of the results).

I've been following every twist and turn of this drama since CES.. and I'm pretty confident on it. The comparisons to NMC have been overblown, and the CE(coulombic effic) can't be determined to be irreversible without more cycles.

Though, I was also bullish on LK-99, so take that as you will. I have a bias towards hoping for breakthrough technology.

@Skiv I was also very hopfull at the beginning but further analysis of the first and second test make me sceptical. Yes, on the NMC part maybe to early or on purpose, that it looked so similar. But the dimension estimates look not that good, that they take different cells for different tests is kind of strange according to their claims, it should easily be possible to use the same cell for all tests. Also they look very similar at the room temperature charging Cycles.

Efficiency seems pretty bad (very high heat production for fast charging), looking forward for the cold temperature test if they are that stable also at low temperatures.

I mean, they did not claim any high efficiency at least.

Still it is very interesting to see, what is coming out, 10% for it us true at the moment for me.

@TobiasWegener The ~90% Round-Trip-Efficiency isn't neccesarilly best-of-class for a cell.. but it's still more than good enough if the other claimed properties hold true.

@Skiv it would be fine, and it is the one thing they didn't claim to be good.

But the implication from the relatively normal ( low) coulomb-efficiency for the chemestry is also not good, it is way to low for the claimed 100.000 cycles.

We will see, I am at may be 5% for maybe true, but I lost most of my faith in it.

@TobiasWegener CE can be reversible, and isn't always a good predictor of cell life.

https://tugraz.elsevierpure.com/ws/portalfiles/portal/72094138/Investigation_of_the_Coulombic_Efficiency_and_the_Superior_Differential_Capacity_Degradation_Analysis.pdf
CE is "misleading with respect to the actual capacity degradation" because it includes "reversible charge loss due to leakage currents."

https://pmc.ncbi.nlm.nih.gov/articles/PMC12216820/
"not all coulombic consumption by parasitic reactions equivalently contributes to irreversible capacity fading."

Boy was I wrong... 😅

@TobiasWegener what convinced you?

@SIMOROBO A German battery expert (still actively working in the field), who before was open that they have something legit and explained what technelical processes could lead to such in improvements (my last long comment, so he was open mindedto the whole thing, before looking closer at the experiments from monday).

Then he explained why the experiments showed that the batterie likely would be dead after only 20 of the shown fast charge cycles (coulon efficiency) to get to the impressive fast charge cycles they just pushes higher voltage through them, which in combination with the relatively high ohmic resistance, let to the sharp temperature increases. Furthermore the stop criteria changed for the high C tests. For example for 5C always when the 26 Ah where reached (thus needing more and more overvoltag, degradating the chemestry with each cycle (batteries typically die hot and full)). Why do that?

And in the test regime a propper baseline was missing, normally one would do 0.1 C charges cyes to get internal resistance, that was missing. Why?

The 1 C cycles suggest an NMC type Lithium battery, but unclear if it is solid-state or not, but the cell performance is quit good/Ok compared to state of the art but not at all as good as they claimed ( there were some size estimations to get volume and estimated energy density it was more like ~300 wh/kg and 600-700 wh/L. Why didn't they weigh the cell or give proper dimensions?

So I am not super sure I would give it maybe 5% that they can deliver something more convincing on monday.

Let's see, but I now less hopefull that there is any thing there.

At least we all get a lot of education in battery chemistry😅

Btw I understand almost nothing about the technology side of this, except that the claims are wild, mildly speaking, and that billions have been put into research in this field all over the world. Thus a tiny Finnish startup managing a breakthrough of this magnitude would be fantastical.

However, 15 minutes of research into the business dealings (subsidiaries in trouble with the authorities for non-existent or unverifiable paperwork), funding (aggressively and exclusively approaching private investors instead of public or industry funding, which by itself is a HUGE red flag in Finland) and employee background (pretty much zero science background, all marketing and business) of Donut Lab/Nordic Nano is enough for me to have 95%+ conviction its a scam.

Not to mention the elephant in the room; there just isn't a single logical reason as to why they wouldn't have posted irrefutable proof of their claims instead of selectively dripping information that doesn't actually refute any doubt. Or they could have, you know, shown even an unverified showcase of a functional prototype in action. So far it's just props and sealed single-issue test packages.

I would love for this to be legitimate but currently there is absolutely no reason to believe it is.

This leads me to put another 300 on No (or yes it is true) soom good gueses what it could really be.

https://m.youtube.com/watch?v=dk-YsWXVJg0&pp=0gcJCWgD5mK_OTUh

I am sorry it is in german, maybe automatic translation maybe helps, if you are interested.

But in short (not so short): This battery is likely printed( as they claimed) it is solid state ( as they claim), it is indideed a battery (as they claimed), but not a lithium ion battery (as they claimed), but instead it is a stacked printed battery (maybe sodium better cyclestability because lower voltage, but that just a guess).

The stacking: cathode, conductor, anode leads to full surface conaction and you avoid the problem (of today's Lithium ion batteries) that you have to collect the current on each layer (sideways though very thin coductor (cuper or aluminum), but if you stack them you can have each layer in a series (current runs through the whole cross section (very low ohmic resistance).

Thus you can adjust voltage as needed (as they claimed) as you can stack just another cell layer to increase nominal voltage of the battery (which is in this case the correct word as you several cells in series (battery, as they claim, also what was in the NordicNano slidedeck) instade of one cell.

Printing is extremely scaleable, think about printing of newspapers, they seem to work with German machine company which has more the a decade of experience printing solar panels and all sorts of stuff.

Solid-state or dry printing you can use different chemestry chinones a chemical that can bind ions in molecular structure exactly formed to house an ion, these are not stable in solvens, but when you have dry process you potentially can.

I am may be at No 20% ( though 80% it is true what they say). That's my 2 cents.

This is so exciting and I think exactly what prediction markets were made for. Looking forward to further test results.

1% -> 0.1%

@robm I have seen this video, and it made me a little unsure but I have several points.

He is claiming that all this people publicly stating false on CES.

He claims that if there were 1000 startups like donut laps, that only one of them would have real product behind there claim. That is very strong claim.

However, I respect that he even put (5000 €) money on it that they use Lithium, I only put allot mana on it.

Yes, he has exerptice in this field as he did his master in solid-state cell chemistry, but he missed the reason why the 90°C shutdown happened (safety regulation from VTT) and he didn't address the improved charging raid for higher temperatures.

He is looking on it from pure, ok this must be some kind of Lithium cell but not considering different production technics like screen printing can use different chemestry and stakking and so on, where big companies 100 of millions in asids (lithiumion cell production equipment), which would be incompatible with screen printing and thus, not what they look for.

May be he is right, we will see, but he seems to me very over confident with his given likelyhoods 0.1%.

Edit, spelling, my spelling is terrible I am sorry.

There is now independent verification of charge rates and capacity: https://pub-fee113bb711e441db5c353d2d31abbb3.r2.dev/VTT_CR_00092_26.pdf

I'm not seeing anything about battery weight or energy density in the third-party tests.

Notably there is no verification of how long it keeps the charge, so the theory of this actually being a supercapacitor and not a battery and therefore not retaining its impressive charge for long which would make it rather impractical in EVs is still plausible.

@SergeyDavidoff the high Temperatur leading to better charging performance, actuelly seems to point to a real solid-state electronlyte. For a capacitor I would not expect such an influence.

Also notable is that the 100,000 cycles claim has yet to have any evidence shown for it. And that's arguably one of the most impossible claims.

Video version

@SergeyDavidoff Doesn't this contract their claims that the battery charges fully in less than 5 minutes?
Also, if the battery is able to sustain temperatures of 100C, why did they stop the test when it reached 90C for safety?

@adonisds reportedly the independent lab has a policy of stopping at 90C, presumably because they're used to testing lithium batteries.

This is a "worst case" test, I'd say if it can charge in under 5 in a best case (reasonable, not submerged in liquid nitrogen or something) that should count. Weirdly, they seem to charge faster with the worse heat sink situation in this test, I'd like to understand that.

@robm If they indeed use a solid-state electrolit, these have typically a temperature dependent diffusion rate (of for example lithium ions), thus you can charge faster if temperature is higher as the resistance goes down (I coauthored this paper about Solid-state electrolides https://www.sciencedirect.com/science/article/abs/pii/S0167273812005942?via%3Dihub).

https://www.youtube.com/watch?v=uiOma6v_EZY

https://www.youtube.com/watch?v=aUT6LPB-Z1E&t=22s

10k YES up at 90%