Donut Lab’s "Solid-State" Battery Exposed as Regular Li-Ion in Damning Investigation: How a $1.25B Battery Startup Fooled the World

The $1.25 Billion Question

Imagine raising over $25 million from more than 1,300 investors, pushing your company's valuation past a cool billion dollars, all on the back of a product that, if the claims were true, would literally rewrite the rules of energy storage.

Now imagine that product was a fake.

That's the story unfolding around Donut Lab, a Finnish battery startup that stunned the world at CES 2026 with claims of a mass-producible solid-state battery boasting an energy density of 400 Wh/kg, a lifespan of 100,000 charge cycles, and the ability to fully charge in just five minutes. The company was valued at $1.25 billion.

But in a comprehensive investigation released June 9, 2026, independent battery researcher Ryan Inis Hughes, creator of the popular Ziroth YouTube channel, methodically dismantled those claims, exposing Donut Lab's "revolutionary" solid-state battery as... a regular lithium-ion cell.

(Yeah, you read that right. A regular lithium-ion cell.)

The "Miracle" Claims that Shook CES 2026

To understand why this is such a big deal, and why so many people were caught off guard, we first need to revisit the sheer audacity of Donut Lab's claims.

At CES 2026, Donut Lab CEO Marko Lehtimäki took the stage and announced that his company had achieved what the world's largest battery manufacturers had been chasing for years: the world's first truly mass-producible all-solid-state battery. But he didn't stop there.

The battery he described wasn't just good. It was perfect.

• Energy density: 400 Wh/kg, roughly double that of the best conventional lithium-ion batteries on the market.
• Cycle life: Up to 100,000 charge-discharge cycles, compared to ~1,000-2,000 cycles for typical EV batteries.
• Charge time: A full charge in just five minutes.
• Temperature resilience: Maintained over 99% of its capacity from -30°C to over 100°C, with "no signs of ignition or performance degradation".
• Safety: No flammable liquid electrolytes, no thermal runaway, no metallic dendrites.
• Cost: Cheaper than standard lithium-ion, using no geopolitically sensitive raw materials.

Lehtimäki even claimed the battery had already entered production and would be powering a new version of the Verge TS Pro electric motorcycle on public roads by the first quarter of 2026.

In the battery world, this was the equivalent of announcing you've discovered cold fusion and a cure for the common cold, at the same press conference.

As Markus Gehring, a battery materials specialist at Germany's PEM Motion, later told Science: "When you combine all of these claims in one battery, it's hard to believe". But at the time, "hard to believe" wasn't enough to stop the hype train.

The Investigation that Cracked the Code

Ryan Inis Hughes didn't buy it.

The Ziroth creator launched a months-long investigation that ultimately involved over 20 independent battery technology experts, including Julian Zanau from the Fraunhofer Research Institute, Dr. Yahim San from Justus-Liebig University, and Tom Bicha from Leona.

The results? Unanimous. Not a single expert reviewed the available data and concluded that Donut Lab had a solid-state battery.

Instead, the evidence pointed to something far less exciting: a standard NMC (nickel-manganese-cobalt) lithium-ion cell.

Hughes was assisted in his investigation by Lauri Peltola, the former Chief Commercial Officer of Nordic Nano Group, which had been contracted to manufacture the batteries. Peltola had already filed a criminal whistleblower complaint against the company, alleging that Donut Lab's promises of energy density and longevity had been overstated. (More on that later.)

For now, let's focus on the evidence. Because it's pretty damning.

Exhibit A – Voltage Curves Don't Lie

One of the first clues came from the voltage curves of the battery cells tested by Finland's VTT Technical Research Centre, the same tests Donut Lab had proudly touted as independent verification of their technology.

The data showed the Donut Lab cell operating at about 3.7 to 3.8 volts at 50% state of charge. That's right where high-nickel lithium-ion cells with NMC chemistry sit.

Why does this matter? Because if the battery used sodium-ion chemistry, as Donut Lab had implied, the voltage simply wouldn't go that high. Sodium-ion batteries rarely exceed 3.5 volts at the same charge level.

Voltage, in other words, was a dead giveaway.

But the voltage data was just the appetizer. The main course, the piece of evidence that truly sealed the case, involved something most non-battery-nerds would never think to measure.

Exhibit B – The "Graphite Kink" that Gave It Away

When you charge a battery, ions are forced into the anode material, causing it to physically expand. That expansion doesn't happen smoothly, it follows predictable patterns that vary depending on what ions are being used and what the anode is made of.

If the anode is graphite (which is standard in most lithium-ion batteries), there's a distinctive "kink" in the expansion curve that appears when the battery reaches about 50-70% state of charge. It happens because of how the lithium ions reorder themselves within graphite's layered crystal structure.

That exact "kink" appeared in VTT's cell expansion data for the Donut Lab battery.

This is crucial because sodium ions are physically too large to fit into graphite layers. They can't produce that signature. The presence of the "graphite kink" proves, beyond any reasonable doubt, that the battery is using lithium ions, not sodium ions.

As the investigation team put it: "It's like we have a slightly noisy fingerprint and a picture of the suspect's face. And yet again, it's a match".

Based on the data, the investigators estimated the battery's actual energy density at approximately 298 Wh/kg. That's actually good for a modern lithium-ion battery. But it's not 400 Wh/kg. And it's certainly not solid-state.

Who is Donut Lab? The Web Behind the Battery

So how did a small Finnish startup with no battery manufacturing experience convince the world it had pulled off a multi-billion-dollar breakthrough?

The answer involves a tangled web of shell companies, aggressive nondisclosure agreements (NDAs), and a CEO with a very specific skill set.

Donut Lab was officially founded in 2024 as a spinout from Verge Motorcycles, an electric motorcycle manufacturer. But the corporate structure is anything but straightforward. The company is registered in Estonia, and its employee roster, at the time of the CES announcement, included just a single technical expert, with the rest of the team focused on marketing and management.

Let that sink in for a moment. Donut Lab, armed with one engineer, claimed to have leapfrogged the world's largest battery manufacturers, companies with hundreds or even thousands of experts and billions in R&D budgets.

Skepticism was warranted from day one.

From "Asinoid AI" to Solid-State Savior

Perhaps the biggest red flag, however, was CEO Marko Lehtimäki's track record. Because before he was trying to revolutionize batteries, Lehtimäki was trying to revolutionize... artificial intelligence.

In 2025, Lehtimäki announced the creation of "Asinoid", what he claimed was the first true artificial intelligence. He wrote on LinkedIn: "Asinoids are..." (and we don't know what came next because the rest of the claim was, shall we say, less than convincing).

Asinoid never materialized. But Lehtimäki simply moved on to the next hype cycle, batteries, with the exact same playbook: aggressive PR, impossible claims, no verifiable evidence, and promises that something extraordinary was just around the corner.

The CT Coatings Connection & Nordic Nano's Role

The Ziroth investigation also traced Donut Lab's battery technology to its actual source: CT Coatings, a German company that had supplied the technology to Nordic Nano, which was then supposed to manufacture cells for Donut Lab to sell.

But here's where things get murky. According to internal emails viewed by Finland's Helsingin Sanomat, CT Coatings had actually abandoned development of the cell that Donut Lab was advertising, shifting its focus to a newer design still in early development.

So Donut Lab was claiming to have a production-ready battery based on technology that even the original developer had moved on from.

Industry experts who met with CT Coatings representatives came away unimpressed. Julian Zanau from the Fraunhofer Research Institute recalled concerns following discussions with company officials: "The first impression I got was that these people have no technical depth".

Whistleblower Speaks: "Their Story Is Now Crumbling"

On April 17, 2026, Lauri Peltola, the former Chief Commercial Officer of Nordic Nano, filed a criminal complaint with Finnish authorities alleging that Donut Lab had overstated its battery's capabilities and lacked the production capacity it claimed.

Peltola didn't just make vague accusations. He provided copies of internal communications between Donut Lab, CT Coatings, and Nordic Nano, along with detailed testimony about the company's operations.

His complaint triggered a wave of renewed scrutiny from the Finnish media. "Their story is now crumbling," Juho Heiska, R&D manager in battery development at Seinäjoki University of Applied Sciences, told Helsingin Sanomat.

Donut Lab and Nordic Nano issued a joint statement denying the allegations, claiming that Peltola lacked "the necessary knowledge of battery technology or the overall picture". CEO Marko Lehtimäki told HS he had no knowledge of the complaint.

But with the Ziroth investigation now providing hard electrochemical evidence, those denials ring hollow.

The $25 Million Question – Where Did the Money Go?

All of this raises an uncomfortable question: How did a company with no verifiable product manage to raise approximately $25 million from over 1,300 mostly small investors, pushing its valuation to $1.25 billion?

The answer lies in a strategy the Ziroth investigation calls "authority laundering", using respected institutions to create the illusion of legitimacy without actually having those institutions verify the claims that matter.

Donut Lab paid Finland's highly reputable VTT Technical Research Centre to conduct tests on its battery. But VTT never addressed the two claims that actually mattered: the 400 Wh/kg energy density and the 100,000-cycle life.

Nonetheless, Donut Lab liberally cited VTT's involvement in its marketing materials, allowing investors to assume, falsely, that the lab had validated the company's core claims.

This strategy worked brilliantly. Too brilliantly, perhaps. Because now, those investors are facing the prospect of losing everything.

Expert Reactions: "Contradictory and Impossible"

Industry experts had been sounding the alarm on Donut Lab since January 2026, but their warnings were largely drowned out by the hype.

The most prominent critic was Yang Hongxin, CEO of Chinese battery giant Svolt. At a January industry event, Yang reportedly called Donut Lab's battery a "scam," stating that its claimed parameters were "contradictory" and that "such a battery simply doesn't exist in the world".

Svolt's engineering team pointed out that the combination of 400 Wh/kg energy density, 100,000-cycle lifespan, 5-minute charging, and extreme temperature resilience violated fundamental trade-offs in battery physics.

"The current lithium-ion batteries in production are in the 175-250 Wh/kg range," noted the skeptical blog Neurologicablog in its initial assessment. "Claiming to have every critical feature improve all at once is beyond a huge deal. That in itself starts to get into the implausibility range".

As the investigation's results became public, even Donut Lab's earlier defenders acknowledged the weight of the evidence. "It seems clear that Donut Lab's CEO engaged in deliberate, calculated deception," wrote Thomas Ricker of The Verge.

Real Solid-State Is Coming, But Not Like This

It's worth pausing here to note: real solid-state batteries are coming. Just not like this, and not on Donut Lab's timeline.

Solid-state batteries use a solid electrolyte instead of the liquid or gel polymer found in conventional lithium-ion batteries. This allows for safer operation, higher energy density (potentially 400-500 Wh/kg), and longer lifespans.

But there are still significant engineering hurdles. Solid electrolytes can have lower ionic conductivity than liquid ones, and interface stability between the electrolyte and electrodes remains a challenge.

Major manufacturers, including Toyota, Nissan, CATL, and Samsung, are investing heavily in solid-state R&D. Nissan has announced plans for 2028 mass production. BloombergNEF estimates solid-state batteries could meet about 10% of EV demand by 2035.

In other words, solid-state is coming. But it's a matter of when, not if, and when it arrives, it will come from established manufacturers with deep R&D pockets and verified third-party testing, not from a two-year-old startup with a single engineer and a set of PowerPoint slides.

The Red Flags We Missed: A Playbook for Spotting the Next Battery Scam

Donut Lab isn't the first battery fraud, and it won't be the last. Previous examples include Envia (2013), Satki3 (2017), and Nikola Motors (2020), each ranging from misrepresentation to investors to outright fraud.

So what can we learn from this case? Here's a playbook of red flags to watch for when evaluating breakthrough battery claims:

• The "one-man-R&D-department" red flag: If a company claims to have outperformed the world's largest battery manufacturers but has less than a handful of technical staff, be skeptical. Battery breakthroughs require deep, multidisciplinary expertise, not one overworked engineer with an outsized LinkedIn bio.

• The "manufacturing-ready-but-we-can't-show-it" red flag: Donut Lab claimed the battery was already in production and would be on the road by Q1 2026. Yet at CES, they showed only an empty case, no actual battery. If the product is supposedly ready for mass production, why can't they show a single working unit in a controlled demo?

• The "trade-secret-shield" red flag: When companies refuse to disclose basic technical details, materials, chemistry, manufacturing process, under the guise of protecting trade secrets, they're often hiding more than they're protecting. Legitimate breakthroughs file patents (which require disclosure) while still protecting intellectual property.

• The "impossible trifecta" red flag: Battery technology involves fundamental trade-offs. You can increase energy density, but often at the cost of cycle life or safety. You can improve charge speed, but usually at the expense of longevity. When a company claims to have simultaneously maximized all metrics, energy density, cycle life, charge speed, safety, temperature resilience, and cost, they're almost certainly overselling.

• The "authority laundering" red flag: Be wary of companies that cite involvement from respected testing labs or research institutions without the lab actually verifying the core claims that matter. Always ask: What specifically did the lab test? What parameters did they measure? What did they not measure that the company is claiming?

What Happens Next for Donut Lab and Its Investors?

The immediate consequences for Donut Lab are unclear but potentially severe.

The criminal whistleblower complaint filed by Lauri Peltola is still under investigation by Finnish authorities. Depending on the outcome, Donut Lab and its executives could face charges ranging from fraud to misleading investors.

The company's $1.25 billion valuation, based almost entirely on unsubstantiated claims, has likely evaporated. And the 1,300+ investors who provided approximately $25 million may be left holding worthless shares in a company whose core product has been publicly exposed as a fraud.

Donut Lab has not yet commented publicly on the Ziroth investigation findings. As of June 9, 2026, the company's website remains operational, though it has removed some of its more extravagant claims.

One thing is certain: the case will be studied for years as a textbook example of hype-driven fraud in the clean-tech space, and as a cautionary tale for investors eager to believe in miracle breakthroughs.

Frequently Asked Questions (Donut Lab solid-state battery)

Q: What did Donut Lab actually claim about its battery? A: Donut Lab claimed its all-solid-state battery had an energy density of 400 Wh/kg, a lifespan of 100,000 charge cycles, full charge in 5 minutes, and maintained over 99% capacity from -30°C to over 100°C, all at a cost lower than conventional lithium-ion batteries.

Q: Who conducted the investigation that exposed Donut Lab? A: Battery researcher Ryan Inis Hughes, creator of the Ziroth YouTube channel, led the investigation with assistance from over 20 independent battery experts, including Julian Zanau from the Fraunhofer Research Institute.

Q: What evidence proved the battery was actually lithium-ion? A: Two key pieces of evidence: voltage curves showed the battery operating at 3.7-3.8 volts at 50% charge (characteristic of NMC lithium-ion cells), and cell expansion data revealed the distinctive "graphite kink" that proves lithium ions are being used.

Q: Did any experts raise concerns before the investigation? A: Yes. Svolt CEO Yang Hongxin called the battery a "scam" in January 2026, and numerous independent analysts expressed skepticism about the impossible combination of claimed specifications.

Q: Are real solid-state batteries actually being developed? A: Yes, but on a longer timeline. Major manufacturers including Toyota, Nissan, CATL, and Samsung are investing heavily in solid-state R&D, with mass production expected around 2028-2030.

Trust, but Verify – The Only Real Battery Breakthrough is Hard-Earned

The Donut Lab story isn't just about one fraudulent startup. It's about a broader pattern in the clean-tech space: the vulnerability of a hungry, optimistic investor base to claims that seem too good to be true.

And here's the uncomfortable truth: those claims almost always are too good to be true.

Real battery breakthroughs don't arrive via press release at CES. They emerge from decades of incremental research, countless failed experiments, and the slow, grinding work of solving one engineering problem at a time. The world's best battery scientists aren't promising 5-minute charging and 100,000-cycle lifespans. They're celebrating when they manage to push energy density up by 5% while keeping cycle life stable.

Donut Lab promised paradise. It delivered PowerPoint slides and a handful of tests that measured everything except the things that mattered.

The lesson? Trust the data, not the hype. Demand third-party validation of specific claims, not just handwavy references to involvement with reputable labs. And remember: if a battery breakthrough sounds like magic, it probably isn't real.