Like glow fuel in F2A and F2D, you need to standardize batteries so you can get them on site.
I can't carry a can of liquid fuel on an airplane. Why should the airlines risk carrying a battery with the same energy content. In reality, a battery can release energy with a simpler failure mode than a container of liquid.
The killer Muslim attacks around the world have caused a drastic upgrading of aircraft security technology. This has had a negative impact on our life style, which is the goal of terrorism.