Earlier this month, a little-known Finnish startup shocked the world when it claimed to have beaten Toyota, Samsung, LG Energy, Quantumscape and any number of Chinese automakers at commercializing the Holy Grail of electric-vehicle power: solid-state batteries.

Helsinki-based Donut Lab said at CES 2026 that it has a class-leading solid-state battery ready to go in an upcoming electric motorcycle, boasting five-minute fast-charging and unprecedented energy density. Hopes ran high that this could be a breakthrough for a battery technology widely seen as capable of changing the world. But then, the doubts started to emerge.

"People love seeing strategic partnerships and manufacturing scale-up," Jiayan Shi, an associate at research firm BloombergNEF specializing in electrochemistry, told InsideEVs. "It would be nice to have data for performance and safety validation," she added.

For their part, Donut Lab executives maintain the technology is real, yet shrouded in mystery to protect their trade secrets. The company says the battery will soon be used in a new two-wheel EV from Verge Motorcycles. "The Donut battery surpasses what most of the industry is still planning for years from now," Marko Lehtimaki, the co-founder and CEO of Donut Lab, said on the company's YouTube channel. "These batteries are shipping today."

Donut Lab and Verge Motorcycles did not respond to a detailed list of questions from InsideEVs about the technology, nor grant interviews with executives to respond to these claims. 

Battery researchers have long described solid-state batteries as a key to solving many, if not most, of the problems with current battery chemistries. They swap out the liquid chemical-based electrolyte with a solid one, promising to eliminate range anxiety, enable ultra-fast charging speeds, perform flawlessly in extreme weather and deliver unmatched safety thanks to its fireproof properties.

On paper, an all-solid-state battery would have no trade-offs, which would be a dream come true for battery engineers and consumers alike. But making them at scale without defects and at a lower cost than lithium-ion batteries is extraordinarily difficult, battery executives have previously told InsideEVs.