Well if you are sure about buildings, I won't argue with you unless someone else says different.  But I'm over 99% sure it used to work on ALL ships (i.e. cruisers), but now it doesn't.  Can anyone confirm whether it used to work on non-capships?  Don't just tell me what the docs or tooltips say - I know what that stuff says.  What I'm saying is, I'm 99% sure that it used to work on stuff outside what the tooltips and docs said.  It used to work on all type of ships.

The Recharger only ever recharged frigates. What you might have witnessed was the Recharger giving antimatter to Disciples, which used Transfer Antimatter on a structure (so you could indirectly transfer antimatter from the Recharger to other structures via Disciples). Problem with that is that the Disciple's Transfer Antimatter requires 100 AM to use in order to donate (I think) 25 AM over 5 seconds.