Overview
- An independent investigation led by researcher Ziroth and more than 20 battery experts reviewed VTT test data and concluded the Donut Lab cell behaves like a conventional lithium‑ion battery rather than a sodium‑ion solid‑state design.
- VTT measurements show the cell sits around 3.7–3.8 volts at roughly half charge and displays a mid‑charge anode‑expansion “kink,” both diagnostic signs of a graphite‑anode lithium‑ion chemistry.
- The tested cell’s energy density calculates to about 298 Wh/kg, well below Donut Lab’s 400 Wh/kg claim and inconsistent with the company’s advertised fast‑charge and extreme cycle‑life promises.
- The investigation traces materials and patents to CT Coatings and names Nordic Nano as a partner, while reporting that Nordic Nano has not manufactured commercial cells and Donut Lab’s CEO said the VTT‑tested units were not the production cells.
- Finnish authorities have been reported to be examining the matter and retail investors who backed Donut Lab—about $25 million from roughly 1,300 participants—face potential financial and disclosure‑risk consequences.