Donut Lab's third independent VTT test confirms its solid-state battery retains 97.7% capacity after 240 hours idle. Energy density and cycle life remain untested.

As part of its 'I Donut Believe' campaign, Finnish battery developer Donut Lab has published further independent test results for its disputed solid-state ...

VTT's second independent test shows Donut Lab's solid-state cell delivered 110% capacity at 80°C and survived 100°C discharge, but key claims remain unproven.

Since announcing earlier this year that it was on the cusp of a major battery breakthrough, Finnish startup Donut Lab has faced a lot of questions, and plenty of skepticism, about its production-ready ...