I wonder what the upper limit on battery density is, not from an electrochemical/physics perspective, but on a simple practical level based on collateral damage?
Like, we're already at the point where your cellphone battery isn't more than a few orders of magnitude away from the energy density of a hand grenade, making a tesla catching on fire a minor crisis for a fire department.
At what point do batteries stop getting more dense, to limit the damage when they fail?
Like, we're not going to get to the point where your phone can last a month on a single charge but if you accidentally smash it in a car door, the resulting explosion takes out the whole block.