RE: Battery discharge rate ?
I assume you are talking about NiCd or NiMh packs.
If so, cycling is a waste of time and effort, (that is assuming your packs are less than 5 years old). Don't buy a cycler or rig something up it's just not necessary anymore.
OLDER packs would benefit from 'cycling', but that is no longer the case.
Charge, fly, charge, fly (repeat). When your pack seems to lose it's charge rapidly...buy another $15 pack.
Enjoy!!