It is still far from commercially viable yet.

Solid-state sodium is still in the laboratory stage. People assumed Donut was claiming to have developed a solid-state sodium battery due to their "no lithium" statement, but they never specifically claimed they were using sodium.

All solid-state lithium is a bit further along. Korea has pilot plants producing full-sized EV batteries that are being used for testing before they do the final scale up to production. Chinese manufacturers are also basically at the same stage. Those will likely be available in production EVs by 2030.