battery health/life %

SuperPete · Oct 11, 2015

So I have few batteries.
TB47's and TB48's

all batts are complete discharged every 10 flights, only charged after about hour of cool down, no extreme hard flying, outside temps are in 70-80F, always land drone at about 20-30% of life left except every 10th flight when I drain them down to ZERO. all I can say batt's are well taken care of.
I came from 3D helicopters (T-Rex 500 and T-Rex 600 electric) of last 7 years and I know all there is about lipo's, charging and taking care of batteries.

all batteries about same story with life % of the batt's.
after 12 charges showing 96% life
20-25 charges showing 95% life
after 30 charges 93% life.

you kidding me? if they keep up like that I figure month from now they'll be 50% life, LOL???

Anyone with resolution on this?

SultanGris · Oct 11, 2015

its an estimate based on whatever firmware youre using. im on older firmware but ive done the exact same procedures as you and after 30-40 charges 2 of mine are still at 100% and one is at 96%. Based on djis past history with firmware and app bugs/lack of coding ability id not put too much stock in it, dont know of anyone whos hit zero battery life or had one fail yet, and ive talked to a few guys with over 100 charge cycles.

SuperPete · Oct 12, 2015

I have 1.4 firmware on all of the batt's.
It's just loosing that much at the beginning of the life of the battery is scary.
From my previous experience our help batt's would take good full capacity charge first 100 charges, than slowly start dropping.
Even 300 charges batt's would be at 80-85% life ( capacity ), and we are talking cheap turnigy packs.
during my years of flying I probably went trough 30 of them, and they all held up allot better than this $250 packs..

I am not afraid of completely running out of battery life, I am talking of taking away my flight time by not charging all the way. 5700Ah minus 20% life is only 4500Ah, right?

SultanGris · Oct 12, 2015

4560 according to my calculator. whats the mah listed when the battery is fully charged? does it go down when the battery life percentage drops or differ from the 96% vs the 93% battery at full charge?

You let them cool before recharging? shouldnt matter anyway, they shouldnt allow charge if they are too hot per the "smart" part, but again their firmware could be dodgy in those regards, lol

Kilrah · Oct 12, 2015

SuperPete said:
I am talking of taking away my flight time by not charging all the way. 5700Ah minus 20% life is only 4500Ah, right?

Makes no sense, it always charges fully. What it does as the "aging" counter increases is that indicated percentage will base itself on decreasing capacity estimation between cycles.

When you do a full cycle the battery learns its real capacity, inbetween it has to estimate (very conservatively for obvious safety reasons) the evolution and it does so both based on cycles and on age.

SuperPete · Oct 12, 2015

if you read my first post I stated that I let battery cool for hour before charging.
Yes, batt capacity showing will drop as battery % life drops.
Full charge discharge do not change my life %