Would solid state batteries really matter much, given the weight floor for the 2026 engines?
I guess you could use solid state batteries to get the overall weight down, then strategically place ballast to optimize CoG, but it's not like you're getting a huge benefit from it since the battery is already at the very bottom of the PU.
I guess there would be some packaging benefits with a smaller battery, but I don't think solid state batteries would be transformative at all for the 2026 cars.