Fossil fuels are currently the largest disconnected power storage by overall power used. You know, the thing cars use when they aren't EVs. You may have heard of diesel and gasoline generators, or oil-fueled ships.

As per the previous part of my comment that you quoted, my point was that incremental changes can accumulate to the point where at some point revolutionary changes can occur. We increased capacity and longevity by a factor of 10 over 30 years, have a new technology hitting mainstream, and another that could double power density in the next 5 to 10. Yet you seem skeptical that's possible, in spite of the decades of advances we already have made.