Even batteries require charge... and batteries are relatively low power flow. In order to get the high power flow that weapons actually need to work, you have to have a capacitor - something that can dump its charge relatively quickly (but takes a while to charge back up).

Capacitors can be found on ScR, ScP, LR and any rail weapon (rails still also have conventional ammo too). Feasibly ScR, ScP & LR could have their capacitors recharged off of just dropsuit power, but it would take a long, long time (hours to days).

In short 'battery' powered weapons would require a whole ****ing powerplant to get working and you'd end up having to drag a cable around behind you in order to fight with your 'infinite ammo' weapon.

Laser weaponry?

You're alive. :o

Wouldn't that technically make the battery the ammo?

Bomb :o <3

My Hair.

How about kinetic energy? Charges the more you run about.

Still technically means the energy is the ammo though... An ammo-less weapon would basically be the nova knives.