yet their energy density didn't grow almost at all in last decade, I don't need cheaper battery, I need battery with significantly higher density, in previous d

yet their energy density didn't grow almost at all in last decade, I don't need cheaper battery, I need battery with significantly higher density, in previous decades density was pretty much doubling every 10 years, but this stopped in 2010, then in last 10 years was density growth how much 10-20% ?