Get some LIFePO4 batteries from a good source. Hangar9 has a digital servo and receiver current meter (HAN172) that will enlighten you to how much your servos and receiver need available when moving all surfaces. I found quite surprising results. Also there is a LiFe-source battery charger (HCAM6375) that costs around 35 or 40 $$ and will charge these correctly from either household current or from your car battery at the field. My NIMH are in the recycle bin at Radio Shack. I found the digital servos can require a lot more power than is available from a NIMH. I had used NiCads before and did not initially understand the NIMH battery's voltage sagged under a higher flight load. Lost an airplane to voltage sag/brownout. Also get educated in "impedance" which is more important than "capacity" -it will surprise you.
Recycle old batteries before they recycle your airplane!!!
I have used one lifepo4 for months now setting up 5 different airplanes, with no loss in voltage, and have placed loads far in excess of flight loads on it, and have not needed to recharge it yet. I will charge before flying, but I am just stress testing it here on the workbench and I am quite happily surprised by its abilities. It is holding its voltage very well and has a lot of time on one charge.
I have also purchased high voltage servos for my next build, may use lipo's but I dont always make the battery packs easily removable, so that may be a deciding factor, lifepo4's can stay in place in your aircraft during charging.
Last edited by marksz1; 01-12-2016 at 05:40 PM.