Finnish startup Donut Lab has released a new report from the VTT Technical Research Centre of Finland confirming the performance of its solid-state battery in extreme cold. The tests showed that a module of 14 battery cells retained 97% of its ampere-hour capacity after being kept at -30 degrees Celsius for five hours.
The company previously announced that its battery maintains 99% capacity at -30 degrees Celsius. According to Donut Lab CTO Ville Piippo, these results were achieved without the use of external heating, cooling, or insulation systems. The battery is designed to function without additional thermal management hardware.
Donut Lab first unveiled its solid-state battery at the Consumer Electronics Show in January. The company claims the battery features an energy density of 400 Wh/kg and supports a full charge in five minutes. VTT has been conducting independent validation of the technology throughout the year.
In March, VTT validated that the battery maintains performance at 100 degrees Celsius. These independent tests suggest the battery does not rely on standard liquid electrolytes, as the membrane breach during testing did not result in fire or significant outgassing. The exact chemical composition of the battery remains undisclosed.
