I just found something weird. In my current game, I decided to not research tanks, as to not clutter the research and workshop interfaces. I'm not really a HWP user.
Buuut, I managed to capture some academy cyberdiscs (hooray arena fireball launcher!!). Turns out that I'm able to manufacture some Cyberdisc/gatlinglaser, but when trying to put it on a ship, it complains about lack of ammunition.
I've had a look at the research tree, and the batteries for the cyberdisc/gatlinglaser are unlocked by the tank/gatlinglaser, which I haven't researched yet. It's confusing.
I suggest that researching the cyberdisc/gatlinglaser manufacture also unlocks its batteries. Alternatively, cyberdiscs could depend on their relative tanks.