Originally Posted by tonytiger20
I too have purchased a lifepo battery. It is a 1450 mah 2s nanotech. The charger set on life settings ended with all voltage at 720 or 360 each cell. What is a safe level to say ok it is time to switch batteries or recharge. I am flying an Avistar 40 with new Futaba 3004 servos five in all. I assume that this voltage will not hurt the servos but I am concerned that the servos are rated for 6 volts input. Any of you have any thoughts? I appreciate it. I also have a load tester from hobbico.
Do not trust voltage on the LiFePo4 cells for when to recharge. You need to measure how much you take from them (during recharge).
Couple of reasons:
- They hold voltage remarkably well
- They drop VERY rapidly when near depletion
Here is what I do. I fly 4 or so flights and recharge. Then you can see about how much you put back in. Then I know how many flights I can get before getting to about 70% discharge - leaving a very safe reserve.
I usually recharge them just before flying every outing too. Just like the old NiCad's we used to use - safer.
Also don't worry but the voltage will drop to around 6.6v and stay there for almost the entire pack. If you ever see 6.4 or 6.3 it is very likely almost completely done.