So how much do batteries have to improve to make small electric energy based weapons practical? If Li-Ion could store double the energy in the same weight and

So how much do batteries have to improve to make small electric energy based weapons practical? If Li-Ion could store double the energy in the same weight and volume would that change the nature of small guns? Just wondering how close we are to a major change in weapons technologies if it all depends on batteries. Maybe there is a certain limit beyond which batteries should start becoming controlled technology? Even current lithium batteries of all kinds are close to being explosives (at least chemically) which is an indication of how much energy is stored in them.