I'm new to planes but not to RC. Running and racing electric RC cars, we deal with battery issues. In electric racing, having a battery that is not well care for is like having a wore out nitro motor.

First off if you use NiMh (Nickel Metal Hydride) you can charge a partially drained battery with no lasting problems. With Nicd (Nickel Cad.) you ideally want to drain the battery before you recharge. Over time a battery that is not fully (fully being to cut off, not completely dead) discharged will develop a memory. The battery may still last a long time, but at some point the voltage output drops to a low level causing a false dump. In electric car racing, you will see cars that go fast then start to slow, this is due to the power loss a NiCd battery has as it goes through the discharge cycle. The memory will cause this to happen sooner. If you look at RC car batteries you see all sorts of matching and time claims and a price reflecting this. This is where they match cell and create the best combination of cells to provide longer more powerful lasting packs. The receiver packs are pretty much all just non matched packs.

Now for the cycling, you don't need a special charger to cycle them. All you need is a car taillight bulb (like a 2257) that you use to drain the remaining charge in a pack before recharge. A single bulb is fine for a receiver pack and will allow each cell to discharge equally. Don't let the bulb go all the way out, you will see it start to go dime as the voltage drops. I let mine go until the bulb element is just glowing red hot. The let the pack cool a bit and charge fully. You don't need to do this every charge cycle, but when you have time and think about it.

With a receiver pack battery, you may not notice the reduction in performance as it happens slowly and you are not demanding that much the battery. As the battery begins to dump (what we call the point at which your battery is to discharged to perform) your servos response will be slower and weaker. I have NiCd packs that are close to 20 years old, they work fine and only lag in the capacity compared to modern NiCd's. I have also got new packs that went to junk in about a year. Like anything, you can get good and bad performers.

With NiCd's a little care, can help ensure long life and reliable discharge while in your plane. Imagine how bad you will feel when you crash your New P-51 due to battery dump.

If I confused you, read up on batteries at some of the RC car sights. Just remember there is a big difference in care between a NiCd and NiMh.