Startup’s ‘miracle’ solid-state battery actually uses lithium-ion chemistry, according to third-party tests — Donut Lab raised $25M and is valued at $1.25B on what now appear to be debunked claims
The 400 Wh/kg energy density claimed was measured at under 300 Wh/kg.
A Finnish startup’s claims to have created a ‘miracle’ solid-state battery appear to have collapsed under independent scrutiny. Ryan Inis Hughes, host of the Ziroth YouTube channel, worked with “over 20 independent battery experts” to investigate the product from Donut Lab. They concluded that the battery was, in fact, a repacked lithium-ion chemistry one. Probably most worryingly, Donut Lab has collected $25M in investments from thousands of small investors. Authorities are now investigating, reports Electrek, what is already being described as the Theranos of the battery industry.
The video begins with Donut Lab CEO Marko Lehtimäki announcing at CES 2026 that his solid-state battery tech is “going to transform the industry.” Donut Lab’s valuation subsequently rocketed to $1.25B off the back of claims its 400 Wh/kg, 100,000-cycle, 5-minute-charging solid-state battery was shipping "in production vehicles."
This startup, coming out of nowhere, boasting of an achievement that the likes of Toyota and Samsung are still working towards, made some suspicious and others eager to invest. But even before any independent technical analysis of a Donut Lab Solid State battery pack could be completed, cracks started to appear in its claims. For example, a whistleblower from a partner company, the ex-COO of Nordic Nano Group, came forward to allege that the CES 2026 outlined battery specs weren’t accurate.
Results of the investigations
Even before any battery characteristic tests or chemical analyses were done, much of the backstory of the ‘miracle’ solid-state battery was debunked. Adding to the whistleblower’s revelation, a Fraunhofer Research Institute scientist who talked to Donut Lab technology provider CT Coatings was agog that “these people have no idea how a battery actually works.” Then there was the revelation that a motorcycle firm partnership was merely at the development test phase. The Donut Labs batteries were not in the “first production motorcycle,” as claimed at CES and on the firm’s website.
Moving on to the scientific analysis of the Donut Lab Solid State battery, things get even worse for the Finnish startup. Scientists and experts from the aforementioned Fraunhofer, plus a number of universities, “confirmed the tested cell is lithium-ion,” reports Electrek.
Two key pieces of evidence point to high-nickel lithium-ion cells (NCM chemistry) powering the ‘miracle’ solid-state battery. Firstly, the voltage curves precisely match a lithium-ion battery. Secondly, the ‘kink’ in the battery’s physical expansion curve around 50-70% state of charge is exactly as expected for a lithium-ion battery. It was also observed by testers that the advertised 400 Wh/kg density was way off, with measurements indicating the Donut Lab battery packed 298 Wh/kg.
Tech enthusiasts might feel disappointed by the apparent hollowness of the battery startup’s claims. However, one must pity the 1,300+ small investors who have put their savings into Donut Lab under what may have been false pretenses. Finnish financial authorities and criminal authorities are reportedly investigating this case.
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Mark Tyson is a news editor at Tom's Hardware. He enjoys covering the full breadth of PC tech; from business and semiconductor design to products approaching the edge of reason.
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Notton If it sounds too good to be true...Reply
Just take a look at the periodic table and it should be obvious.
There's a reason the (Li) Lithium battery was a breakthrough, and now we're working on (H) Hydrogen and (Na) Sodium for applications that don't need to be as dense and light. -
Scott_Tx How many times do you have to see these scams not to be fooled by them? Would anyone like to invest in my free energy device?Reply -
usertests Reply
At least solid-state batteries appear to be coming. But not Donut's version of it.Scott_Tx said:How many times do you have to see these scams not to be fooled by them? Would anyone like to invest in my free energy device?
https://electrek.co/2026/06/08/donut-lab-solid-state-battery-exposed-lithium-ion-fraud/My biggest concern now is that this damages public trust in solid-state battery technology more broadly. I hope it doesn’t cool people on the technology, because solid-state batteries do appear to be genuinely, finally coming. Toyota has invested over $15 billion and targets production vehicles by 2027-2028. Samsung SDI has the world’s largest pilot solid-state production line and plans mass production by 2027. These are real programs from companies with real technical credibility. Solid-state is coming — just not from Donut Lab, and not with the impossible combination of specs they promised.
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JTWrenn The guy pushing this had so many red flags that the rest of it kind of didn't matter. If you took the risk on this after all those flags you were just flat out gambling.Reply -
JohnyFin Today's technology is very advanced. To push boundaries further you need huge investments, best scientists.Reply
Startups are scams, people are greedy Believe in tech revolutions. Most startups redesign only actual technology. -
nameless0ne I wonder what was the planned end game? The founder is based in Europe. The CEO of Nikola trucks had to buy himself a pardon in order to weasel out of his own fiasco. It is unlikely to work out like that in this case.Reply -
Hooda Thunkett Reply
How many Beanie Babies per share of that free energy device? /SScott_Tx said:How many times do you have to see these scams not to be fooled by them? Would anyone like to invest in my free energy device?