Did you mean to say sodium batteries instead of lithium in your "BYD did it" sentence?
No. Five years ago BYD introduced their "blade battery", which is a lithium iron phosphate battery built up of plate-like "blades" in rectangular casings.[1] Wh/L is about the same as lithium ion, Wh/Kg is not as good, and Wh/$ is better. It will survive the "nail test" and does not not go into thermal runaway.
Today, most of BYD's products use this technology. It's been improved to handle higher charging rates. Seems to work fine. Lithium-ion has better Wh/Kg, and it's still used in some high-end cars, mostly Teslas. BYD's approach has captured the low and medium priced markets.
BYD has announced that they plan first shipments of cars with solid state batteries (higher Wh/Kg) in 2027. Price will be high at first, and they will first appear in BYD's high-end cars. Like these.[3] BYD has the Yangwang U8, a big off-road SUV comparable to the Rivian, and the Yangwang U9, a "hypercar". Just to show that they can make them, probably.
[1] https://www.youtube.com/watch?v=dIt5z4wT9RE
[2] https://electrek.co/2025/02/17/byd-confirms-evs-all-solid-st...
> Like these.[3] BYD has the Yangwang U8, a big off-road SUV comparable to the Rivian, and the Yangwang U9, a "hypercar".
I really did not expect to open this and have it be presented by Kryten! Fun surprise! :)