i use RC 9.6 volt batts for Nbox battery pack. 4 separate batts. the nbox batt input makes them run in parallel or concurrenct. dont seem to need much maintenance. but i charge them one at a time, and i usually try and take alittle break between batts as they do tend to heat up. and i always like to " break " them in. charge full. run an hour or two. charge full again, run twice as long. recharge, and run down to no less than 10%. start your trun times on the third charge. make sure not to drain the battery to zero. check time at around 10-12 % , recharge fully. killing a battery when new can make them flacky i alway thought. plus the 10-12% is your leway time. say u get 4 hrs 15 min when the batt is at 12%. so u know after 4 hrs of run time to get ready for a batt change. but when done charge everything up again, and run till 10-12% again. times will most deff be going up. i did that so when the buyer would recieve the battery pack and need be in a hurry. its all preped and ready for action. forget. think it was 17 to 25 hrs of run time for the 4 rc batts. light too!
the 7.2's rc batts i used on SD 702. had a dummy cell with a pigtail with RC batt ends wired in parallel. with an extra plug for hot swapping, but they ran for ever. that were i got the nbox battery ideaish. the only thing they did shit on was when i tryed to use them in series to make 14.4 volts on a ad/1000. they dont drain like sealed lead acid, even though the MAHs said different. when they die, they die. esp there readings after being used. like lower than the threshold of not working, because of using them in series. the apogee would flash at 11.8 and die like at 11.1 volts. so that made the 7.2 volts that brings the voltage down on both batts around 5.2-5.3 volts. don think they normally drop that low before dieing. was just looking for a diff way to power the ad/1000 with out the lead. but been using elsewhere when ever im looking for battery power. easy to charge. tons of sizes and shapes. the RC connector works nice and isnt cheesy and doent need to be soldered, but i alway do.. but anyway. they r great options with alittle work. shopping for the best buys, and prob making cords or plugs. but i do that shit any way. get a mulit meter. easy to use use. will be your new best friend. and save u tons of time. ed