DO NOT WORRY ABOUT BATTERY MEMORY.

To ensure you always go flying with a full charge go to your favourite discount electrical store and buy a cheap 24 hour timer switch

like http://www.presentsforyou.com/e1020cintermatic.html?

Plug your charger into this and set it to charge for 1 hour a day.

When you come home from flying use the over ride to charge for 6 hours if you had 2 flights - 12 hours for 6 or more. [ pro rata ]

[BTW 6 + flights on standard rx packs is pushing your luck. ]

Then the timer will top it off everyday.