Donut Lab Claims Solid-State Batteries Will Enter Production This Year

Finnish start-up says its batteries will enter production this year, but experts question some of the claimed specifications

Finnish start-up Donut Lab says it has made a breakthrough in solid-state battery development. These batteries are regarded as the “holy grail” of battery technology because of their high energy density, long service life and potential for rapid charging. Donut Lab, a spin-off from Verge Motorcycles, claims its batteries will enter production as early as this year.

Donut Lab solid-state battery claims and test results

Experts remain sceptical because the company does not have an established research track record or published scientific data. Nevertheless, Donut Lab has released findings from independent tests carried out by Finland’s leading state research and technology centre, VTT Technical Research Centre of Finland. The tests confirmed the battery’s stated specifications: an energy density of 400 Wh/kg, charging in 5 minutes, a lifespan of up to 100,000 cycles, and resistance to temperatures ranging from -30 to 100 °C. The batteries contain neither rare-earth elements nor flammable liquid electrolytes.

Unproven specifications and reliability concerns

However, crucial characteristics including chemical composition, density and service life have yet to be proven. Donut Lab’s batteries experienced vacuum-sealing issues during thermal testing, raising questions about the technology’s reliability. Experts, including members of the scientific community, point out that solid-state batteries face the risk of dendrite formation: metallic cracks that can cause a short circuit.

Chinese solid-state battery development advances

While Donut Lab continues working to resolve these shortcomings, China is making active progress with solid-state battery technology. CATL recently filed a patent for batteries with an energy density of 500 Wh/kg and intends to begin small-scale production in 2027. Other Chinese companies, including FAW, also say they are ready to integrate their batteries into electric vehicles.

Donut Lab says that “its technology poses a threat to major market players”. The company’s chief executive, Marko Lehtimäki, said industry resistance would only intensify despite the evidence. The company has also announced a second battery version, designed to be more production-ready, which will begin shipping to customers at the end of the year.