Solid state batteries already exist, but they’re unreliable. A few bus companies have been messing around with them over the last few years, even putting them on public roads. One had a huge recall when they started delaminating after a year or so.

They are not as safe, light or as good as advertised. Yet.

After delaminating, some caught fire.

Most wet chemistries (LFP) are safer than current dry chemistries.

Donut claim they have GWhr manufacturing capability. The way they claim that feels very third-person.

That being the case, chances are they just white-labelled someone else’s cell technology and packaged the cells in a box (this is super common, virtually every company in eMobility does this with CATL/LG/Sony cells).

Technically it’s a battery made by Donut, yes, but in that case Donut don’t have the valuable IP so don’t be so quick to jump to buy shares or whatever. Making a battery box is fairly easy.