LiPo Battery

This site shows my experiences regardoing LiPo batteries


Overview

Brands

I have experiences with 4 brands:

Battery characteristics

In the beginning I used 3S batteries for all UAVs, 2S for the small UGVs. Now I moved moved to 4S for small UAVs, 5S and 6S for lager ones.

Battery maintenance

It seems there have to be some important things to be considered, otherwise the batteries die soon.

  1. Never ever, let any cell go below 3.5 Volt, also under load. The FlightControl is configured to perform an automatic landing at 3.3 Volt. Since I'm follwing this rule, my batteries puff considerable less.
    Unfortunately it seems to be almost imposible to keep the batteries hard, especillay if the total flight time is only over 10min.
  2. Berfore using them, I check the voltage differnce between the cell with the lowest and the highest voltage. If it is hinger than 0.08V then I balance the battery. Otherwise there is a risk that one single cell goes below 3.2 Volt in flight, due to technical reasons, I'm only measuring the total voltage in fligth.
  3. Batteries should not go over 40°C. This is usually the case, if the battery is empty in less than 10min.
  4. When connecting two batteries in paralell, I ensure that the total voltage difference is below 0.05V. Otherwise there will flow too much energy between the batteries.
  5. I'm charging the batteries outside in a fireproof location.
  6. I'm still searching for the point, when a LiPo batterie is too puffed to be used.