donut lab says solid‑state battery will enter production this year

At a glance:

• Donut Lab, a Finnish startup, claims its solid‑state battery can reach 400 Wh/kg and charge fully in five minutes.
• The company posted independent VTT test reports but has not yet verified chemistry, density or 100,000‑cycle life claims.
• Major players such as CATL, Toyota and Mercedes are also racing toward solid‑state EV cells, with production targets set for the late 2020s.

What happened

Earlier this year Donut Lab, a spinoff of Verge Motorcycles, announced that it had finally solved the solid‑state battery problem and would move the technology into production later in 2024. The claim was accompanied by a dedicated website, idonutbelieve.com, that promised to publish third‑party verification of the battery’s performance. Over several weeks the startup shared five test reports from VTT Technical Research Centre of Finland, which it said confirmed a fast‑charging, high‑energy‑density cell that was not a disguised supercapacitor.

At the Consumer Electronics Show in January, Donut Lab disclosed a set of headline figures: an energy density of 400 Wh per kilogram, a full charge in five minutes, an operating temperature range from ‑30 °C to 100 °C, and a projected lifespan of 100,000 charging cycles. The company also highlighted that the cell contains no rare‑earth elements, precious metals, or flammable liquid electrolytes. These numbers, if true, would double the energy density of typical lithium‑iron‑phosphate (LFP) packs and dramatically reshape electric‑vehicle range and safety.

Expert skepticism

Solid‑state batteries have long been labeled the “holy grail” of energy storage, but most attempts stall before reaching commercial scale. Eric Wachsman, director of the Maryland Energy Innovation Institute, cautioned that Donut Lab “has not demonstrated” the core claims, noting the absence of published chemistry, verified density and cycle‑life data. During VTT’s extreme‑heat test the pouch lost its vacuum seal, a failure that could indicate gas generation or electrolyte decomposition—issues that are hard to assess without a clear cell chemistry.

The skepticism is amplified by the startup’s low profile; unlike industry giants, Donut Lab has no known academic pedigree or prior patents in solid‑state research. Marko Lehtimäki, the company’s CEO and co‑founder, acknowledged the controversy in a video posted on April 1, stating that the “100,000 cycles” figure is a design target rather than an experimentally proven result.

Technical claims and gaps

Donut Lab’s published data focus on performance metrics but omit the underlying materials. The company asserts the battery is free of rare‑earths and precious metals, yet it does not disclose whether the electrolyte is sulfide, oxide or a hybrid, nor does it reveal the anode or cathode composition. Without this information, independent labs cannot fully reproduce the tests or assess long‑term reliability.

The VTT reports did confirm rapid charge acceptance and a high gravimetric energy figure, but they also highlighted a vacuum‑seal breach at high temperature, raising concerns about gas evolution and potential swelling—classic failure modes for solid‑state cells. Moreover, the promised “practically unlimited lifespan” remains unverified; the longest published cycle test in the reports covered only a few thousand cycles, with extrapolations based on charge‑rate and temperature models.

Industry context

Donut Lab is not alone in the race. China’s CATL filed a patent for a solid‑state cell claiming 500 Wh/kg and aims for small‑scale production by 2027, with automotive‑grade volumes expected by the end of the decade. FAW announced a “liquid‑solid‑state” lithium‑rich manganese cell also targeting 500 Wh/kg for vehicle integration.

Japanese automakers are pursuing parallel paths: Honda is betting on sulfur‑based electrolytes, while Toyota promised “the world’s first practical use of all‑solid‑state batteries in BEVs” by 2027‑2028. Mercedes, using a prototype from startup Factorial, demonstrated an EQS sedan with a real‑world range of 749 miles.

Alevtina Smirnova of the NSF Industry‑University Cooperative Research Center noted that the United States lags behind China’s coordinated investment in battery R&D, which could accelerate mass‑production timelines.

Next steps for donut lab

On April 1, Lehtimäki revealed a second, more production‑ready version of the battery that will begin shipping to customers later this year. While the company plans to roll out the cell, it also launched a merchandise line—including a “tin‑foil‑covered” bucket hat—suggesting a dual focus on brand building and technology validation.

The coming months will be critical: independent labs will need to replicate the VTT results, disclose the cell chemistry, and verify the long‑term cycle life. If Donut Lab can substantiate its claims, it could force established players to accelerate their own solid‑state programs. If not, the announcement will join a long list of premature solid‑state promises that have yet to materialize.