Anyway Solid State Batteries would start in premium vehicles, where 2x cost per KWH would not matter. As long as they show the benefits with less weight and good performance while being safe, it will ultimately hit mainstream vehicles. Most probably sometime next decade.
The mass production cost of solid-state batteries is about to drop precipitously with a target price of $150 per kWh. Gotion's new Gemstone solid-state battery cost is going under the key 'one yuan per Wh' metric.