Lipos Dying Early?


I bought fresh Tattu 3S 75C 450mah lipos 4 months ago from Tattu’s website for my micro quadcopter. My micro quadcopter has a burst amps of 20A and a continuous flying amps between 4 and 8A. I cycle six lipos per flying session, parallel charge at 1C, and put them to storage charge at the end of the day (3.8V). Each lipo has 26 flights on them.

My FC has a current sensor and I land after 420mah are used. Around flight 20 my resting voltage after I land was 3.74V per cell. Now, after flight 26 my resting voltage after I land is only 3.7V per cell.

Are my lipos dying already?!? Do current sensors drift so I need to recalibrate? Am I doing something wrong in my charging process?

I really thought Tattu would last longer…



That’s too small a difference to really be reliable, your FC sensors are not 100% accurate, and they’re accuracy varies over the load as well, they may be less accurate at 6a than 20a for example. In that case a reading of 400mAh might actually be 400mAh if read at 20a, but that same reading of 400mAh read at 6a might actually be 350mAh.

That said, figure the battery is junk after 100-200(at absolute most) flights, and that minor of a degradation is very reasonable for a battery 25% of the way through it’s service life.

What do the cells sag to under full load?


a difference such as 0.04 is too small to be significant unless you average it over a large number of flights.

Stuff like temperature, flight aggressivity, bursts, etc could easily outweight it


Normal bursts take me down to 3.4V, but once I saw it drop to 3.25V. These lower values are nearer to end of flight, so the cells are already getting low.


Everything normal here. Ohh and lipos usually don’t forget a single bad treatment. I would say 100 cycles max. isn’t too bad.


Looks like current sensor drift. I managed to get two successive flight sessions in and compared the mah actual to the mah charged and I used about 50mah per lipo more than was read.

I did calibrate this almost perfectly a while back.

I’ll just land earlier now. :wink:


The life of the battery depends on how you use it.