Posted on 02/25/2026 8:02:48 AM PST by GenXPolymath
Donut Lab commissioned VTT to validate its bold solid-state claims, and the results show near-full capacity retention even after ultra-fast charging...
Rapid charging under test
VTT Technical Research Centre ran the tests in what engineers described as a worst-case scenario.
The lab did not use active temperature controls. It also let the cell’s heat rise freely at high charging rates.
Experts measured performance using C-rates, where 1C equals a one-hour charge from empty to full.
Under that scale, 5C roughly equals a 12-minute charge, and 11C is about a five- to six-minute charge.
The process began with a standard discharge test at 1C. Rapid charging followed at 5C and 11C under both cooling configurations.
At 5C, the battery held up well, reaching 80% state of charge in about 9.5 minutes and 100% in just over 12 minutes.
After discharge, the cell retained all its stored energy. These results align with the five-minute charge claim the company previously announced.
Extreme speeds, full capacity
Donut Lab then pushed the cell to even higher charging rates. At an 11C rate, the battery reached 80% charge in 4.5 minutes. It hit full capacity in just over seven minutes.
When discharged after this rapid charge, the cell retained between 98.4% and 99.6% of the energy it had stored.
These figures show the battery’s ability to handle intense power input without huge losses.
Unlike many solid-state concepts being developed in labs, Donut Lab’s design performed these tests without requiring active cooling systems.
It also did not need unusual pressure or compressive force on the cell to work effectively.
They show the cell it’s a pillow pack which most EV cells are moving too because they can make blade packs like BYD does with their BYD Bladepack at the size they show it and 400wh/kg that almost assuredly was a standard 100ah pouch cell configuration. This is exactly what BYD would use and I would think that is not a coincidence. Small start ups don’t have the manufacturing ability. They will sell it to BYD or CATL that much the more I look at it the more sure of that.better to get paid then it stolen and get nothing.
“When does Donut Lab go public?”
That’s right! If this is legit, that’s what I want to know, too. 😊
“We may be facing a future in which we have actually good batteries with better capacity, far greater life expectancy, and just a better storage system all around.”
Perfect is the sworn enemy of good enough.
We have LFP tech it can do 10000 cycles to 80% SOH at 160-200wh/kg and it doesn’t have flammable electrolytes in most LFP types. Case in point BYD Bladepack passed the steel spike test didn’t burn barely heated up.
BYD just released their 14.5 megawatt hour 20ft iso sized power bank. It has a LCOS of 1.4 cents per kWh round trip and lasts 10000 cycles. If we didn’t have tariffs that pack would be dominating the power storage and back our market. It could run a full sized Costco for 14 hours alone off a single parking spot sized area. Game changer hands down.
CATL has sodium ion cells that do 10,000 very fast 5C cycles and 50000+ 1C cycles with a full operating range of -40 to 70C no cooling or heating needed at either extreme those cells only lose 10% of capacity and that comes back when you get back to the middle of the temp range. Here again these cells cannot burn they use an aqueous electrolyte completely non-flammable the sodium is an ion form it can no more burn than table salt can we have the near perfect batteries already it’s ever increasing energy density that drives the push for battery development going from 180 or 200 to 400e.g./kg makes a large difference.
“When does Donut Lab go public?”
That’s right! If this is legit, that’s what I want to know, too. 😊”
Probably never they will sell to a large manufacturing giants and retire billionaires from the royalties. That’s what I would do. Sell to CATL who already makes sodium cells so they have the supply chain already and economies of scale.
Those mighty Finns; out the door first; remember Nokia.
Interesting but I will wait till these hit the commercial market and whether or not they meet expectations before praising.
Also, if these things aren’t made to be economically recycled it’s just more e-waste heading to the landfills.
Does it go flat as fast as it charges?
All cells have some self discharge as the diffuse back. Solid state cells should be super low because there is no liquids to dissolve into.
As for flat as in does the rate flatten out yes all cells solid or not flatten out as the ions pack more and more into the anode that is electrochemical. They show 4.5 min to 80% and 7 to 100%
You normally stop at 80% so you don’t cause unnecessary stress on your anode. Sodium cells can take DOD all the way to zero something li cannot do well. So unlike a lithium cell currently where your operating window is 80-20% sodium based cells do 80-0 you get 20% more window and if you are willing to give up some cycle lifetime you can do 100-0..with 50000+ cycle lifes for Na based cells you could cut that in half and still beat the pants off LFP at 10000 cycles or NMC at 3000 both current state of the art. Your smartphone uses a NMC cell, laptops too.
Sorry all cells have some self discharge as the ions diffuse back into the electrolyte. 0.5-3% or so per month is common for NMC and LFP chemistry, sodium ion liquid cells 1-5% per month. Solids should be close to zero.there is no where for the ion to go.
Yes, alread was told that, still deems to have information missing. Why didn’t the headline state the 100% right off the bzat? I don’t have time to read every article completely. So, I ak questions to allow people who have read the fl article to tell me what want to know. Can you blame me, in a world that ha more information than anyone can posibly absorb. 😁👍 Thanks you for assisting me in my shortcut tactic. 😁👍
Well if you are going to landfill something, glass/ceramics,salt,aluminum foil and plastic bag is not something we don’t already landfill by the millions of tonnes per year in municipal landfills.
These cells will have no heavy metals, no toxic or corrosive liquids, the sodium is in ion form probably a salt or carbonate, cathode is carbon based , or silicon carbide or carbon, could be Prussian Blue or white both of those are carbon,nitrogen and iron based. The blue is what makes blue jeans blue btw it’s a water soluble dye.
The market will determine if it’s worth it to recycle the materials or not. We don’t recycle alkaline batteries as is now and those have caustic liquids in them they are thrown away by the billions of individual AA and AAA per year full of manganese , zinc and aluminum and copper too. It’s simply cheaper to mine more and landfill the old ones no one blinks at it. How many smartphones do you throw away per year? Tablets and laptops too. That the market we are talking about. Large packs will be regulated simply because of the dangerous voltages involved you will never landfill a EV sized pack those will have to be disassembled and safed the individual cells might be landfilled but if you took them out you can now easily grind them up to black mass and leach the metals out cheaper than mining and processing them for sure copper and probably aluminum too the salt is well salt it’s dirt cheap literally.
They did give the 100% it’s in the same sentence at the 80% in the actual article not just the title.
7 min from zero to 100% and 4.5 min to the 80% where batteries are actually used at.
You do not charge to 100% on packs that are expected to do thousands of cycles you stop at 80% to protect the anode why is this so hard to understand the whole industry does this it is the standard for secondary cells of ionic chemistry be it lithium or sodium and when magnesium and calcium cells comes out they will also be to 80% it is a limit of carbon based anodes it doesn’t matter what ion you shove in as you get close to full capacity the atoms get crowded.
So from a real world use view point the zero to 100% is irrelevant the whole world uses 80% as “full” and if it’s a NMC cell 20% is “empty” not zero. Even LFP cells don’t like to go to near zero 5% and the BMS will stop you and tell you it’s empty to keep you from turning your pack into a brick.
Sounds promising but knowing the actual temperature rise is essential and not stated.
Thanks. I did not watch the video so I plead ignorance.
To be honest, I can read much faster then a video voice talks, so I prefer text. Unless the “gizmo” or process being explained is convoluted or difficult to explain
I am sure as they move from lab to preproduction testing they will have to include some fan based cooling the point here was they were able to push 11C worth of current into it and 1 it didn’t melt down or puff up and bent gases. And 2 they used passive aluminum plates as heat conductors then removed 50% of that and left the top open to bare air without forced air on it. What this shows at the very least is the internal ohmic resistance is low enough it didn’t turn into a joule heater. This was as much a torture test as a shut the haters up test. Beautifully done take it charge it as fast as you can pull half the heat sink away and charge it as fast as you can again. This was a proof of concept test. From the curves and retained energy concept proven 98-99% at a charge rate that would melt a NMC cell even with heroic liquid cooling as full blast. Then pull half the sink away and say hold my beer and do it again. Yeah concept proven. Good on them this is how you science with a flair of suck it haters at the end.
Slight correction: Prussian blue is NOT considered water soluble. In its microcrystalline form it can form a “colloid” not a solution
Also, the dye “indigo”, natural or synthetic is the predominantly used dyes to make blue jeans.
Prussian blue can be used to make fabrics blue, but is mostly used in paints, inks, blueprints, laundry bluing.
Because it is a colloid it can eventually wash out
FYI
Jeans were history dyed with it here and it’s nature was exactly the reason old jeans faded faster. Way before acid washed and synthetic indigo took over. Jeans in India and other places concerned with cost still use PB as it’s cheaper if not as durable as indigo dyes.
Literally the first sentence.
“Prussian blue (PB), a well-known pigment used to dye jeans, has been recognized as an emerging material for next-generation batteries. A team of researchers, led by Professor Hyun-Wook Lee in the School of Energy and Chemical Engineering at UNIST has made a significant breakthrough in the development of low-cost, high-performance lithium-ion batteries (LIBs) using PB, leading to significantly reduced battery prices.”
This also highlights how close lithium and sodium are and ionic chemistry the fact that most sodium ion batteries use this already for their cathode and now they’re going to use it with lithium just shows how close they are.
How quick long does it last on a cold night with the heat on driving back mountain rodes?
EVs suck. I’ll take a high horsepower V-8 with a great cam and headers any day. Loud and proud.
Is this Samsungs Silver battery? They are very careful not to mention Silver battery as Silver is in a mining deficit, and the U.S. Crimex is close to defaulting on Silver deliveries.
I noticed that was left out of the story
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