Most of the solid state batteries have far less thermal runaway problem than lithium-ion batteries. At this point, several companies have working demo solid state batteries, but the price is far too high. Mercedes has one demo car with a solid state battery. Ducati has one motorcycle. Donut Labs just has one demo cell, not even enough for their motorcycle. The technology works but is so expensive there aren't even multiple prototypes.

Samsung says they will ship some solid state batteries in watches and earbuds this year, where the batteries are so tiny they're affordable. Even solid state batteries for phones are still too costly. Everybody in the industry is trying to solve the production price problem. Consensus is that the price starts to come down around 2028 or so.

Lithium iron phosphate batteries don't have a thermal runaway problem, either, but they have about half the Wh/Kg of lithium-ion, so they're not popular for portable devices.

Ten years out, lithium-ion batteries will probably be obsolete technology and totally prohibited on aircraft.

> Donut Labs just has one demo cell, not even enough for their motorcycle.

They sent in multiple cells for lab testing, but more importantly the second Donut demo was a motorcycle charging.

So wait if solid state is too expensive? What replaces lithium ion batteries? What breakthrough do you expect in solid state to make it cheaper in 2028?

What is your take on Lithium-Titanate (sp?) cells?