I think he means "Small Energy Cell"

(That would be my guess too, i wish i could tell from the schematics from OA, as they showed what the insides looked like durring a load screen.)

Should still keep Pip-Boy(Obviously) but it should not pause the game when in use, it should be real time at all times and you can wield a one-handed weapon while in use(Just in case you run into a Mutant or 2;) ). I will try to draw a picture so you can get what I'm saying. The Pip-Boy should be shown on the right arm at an angle and the weapon in the right.