Except tesla is expecting and has been achieving 10% density increases in the last few years. Do this for 8 years, and you get double, same as the new battery tech that's gonna take 10 years.

1st gen: 276 Wh/kg (2022)

2nd gen: 305 Wh/kg (2023)

3rd gen: 333 Wh/kg (2024)[1]

Here is a cool article on all the tech that is scheduled or went into these new 4680 batteries and getting the energy density up well past 300.

https://cleantechnica.com/2020/09/22/everything-you-need-to-...

[1]https://insideevs.com/news/598656/tesla-4680-battery-cell-sp...