It’s a 11.1 v, the 1st cell and the 3rd one go over 4.1vbut the middle one stays at 3. It’s 1 year old though.
Then dispose of it and get a new one, it’s done.
Should I get a 3CS 3300 mah of 4CS 3300 mah for my hexa?
Subscribe to eCalc as I suggested and you can determine what components, battery power and weight will work. But it will have to be 4S and you will want more capacity than 3300mah.
Probably a 4500 mah would work?
Hey,
I bought a 5500 mah battery, yesterday’s flight was good. the quad was stable. But today after few miniutes stable up in the air, it came crashing down disbalanced. Seeing the battery graph it came down to 7 volts, is that what caused this?
Here are the logs, Also the drone drifted on its own, there was no wind , then too it drifted backwards.
https://drive.google.com/drive/folders/1Gv4Bb8WlMuELfAB41wAF7tMBjxq7MjGl?usp=sharing
Yes depleting your battery down to 7V will crash your drone.
Why did you not configure the battery failsafes? It would have prevented your crash.
Hey, thanks for replying.
Is this how a typical voltage graph of a flight is supposed to be?
In the graph it shows 7.7 volts, so what is the minimum voltage it needs to crash? Exactly 7 volts? I read somewhere that these bat levels are the levels during the flight. Is this so? This battery falls due to throttle input usage or just the level of the battery? Can this be caused by something else that spiked my battery to dip getting my quad unstable? I did not measured the actual voltage using a meter just after the flight.
Last time i configured the battery failsafe it turned back to me, do you recommned any good video or website to implement. Also, is seeing the battery graph dip to 7 volts enough to determine a crash?
A typical voltage graph is similar, but it stops before completely depleting the Battery. Because typical vehicles have failsafes configured and active to prevent that from happening, yours does not. Batteries discharge, they are not an unlimited source of power.
Failsafes do not cause your vehicle to crash. Not having falisafes does crash your vehicle.
No, 7 Volts is not a magic number at which all vehicles crash. It depends on a lot of factors like the weight of the vehicle, but for a 3S battery 7V is definitely not enough. You are damaging the battery in the process.
Either you didn’t charge that battery fully before flight or you didn’t calibrate the battery monitor. And as @amilcarlucas says you will damage the battery discharging it so low. Set the failsafe for ~3.4 V/cell.
Hey dave,
I charged my battery to 76% using the imax balance 6 charger. I did not see the voltages. Is this possible that even when the battery voltage was low, the drone kept hovering and did not loose thrust instead lost at a sudden moment. How to be sure that it was tha battery charge that didn’t lasted and not something else, that caused it to come ramming down. I mean it should show some sign of loosing power and start descending maybe or not vertically gain acceleration? The throttle input etc were working absolutely fine. Just after 10 secs of me playing with the throttle stick up and down in stablize mode, making the drone gain altitude and loose quickly to check its vertical acceleration, it lost balance while hovering and came ramming down.
Why do that? Fully charge it. And calibrate the battery monitor using a voltmeter.
At some voltage the ESC’s may shut down so there is no expectation of a soft landing. You discharged that battery way too low, it’s that simple.
Okay dave, thnx for the insight. Ill try this Monday morning and update.
These are the battery-related settings you need. Resist any temptation to change or ignore them, set them exactly as shown here.
BATT_ARM_VOLT,11.00
BATT_CRT_VOLT,10.50
BATT_LOW_VOLT,10.80
BATT_FS_CRT_ACT,1
BATT_FS_LOW_ACT,2
MOT_BAT_VOLT_MAX,12.60
MOT_BAT_VOLT_MIN,9.90
Look up the documentation for your ESCs and disable the low voltage cutoff, or set it as low as it will go.
If you battery charger doesn’t say anything sensible then get a real one that shows voltages, current and milliamp hours. There’s plenty of cheap copies out there that probably dont work properly.
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Hey dave
This is what i saw this morning.
Is this normal?
And the charge percentage was shown 60% approx
No, that is not normal, that battery is damaged.
So here’s what happened, I plugged it in to my old imax B3 charger which basically doesn’t charge the cell 2 of any battery, so what it did was, it charged the 1st and the 3rd cell to green or full and the 2nd cell was still on red and i took a flight. Today I tried to charge the battery with the B6 evo charger, but turns out that the 2nd cell was not going past 3.60 volts, rest both the cells were going to 4.20. Now i read somewhere that charger does not charge 1 cell if 2 cells are alredy full, discharging the battery and then balance charging to 100 will get me to solve this. So i’ve managed to drain the 1st and the 2nd cell to 3.8 volts. Just wanted to confirm that i should proceed with balance charge. Am I doing this right? The battery is just a week old. How can i revive it?
Regards.
Get a working charger. Manually discharge the cells one by one to the same voltage. Balance charge them afterwards
Thanks for the reply, as mentioned, i’ve thrown the b3 old charger and now i have the new imax b6 evo. Will this help? And how to manually discharge each cell one by one? My charger just shows discharge option. Also i came across another way of charging the battery not through the balance port but through th main port and charge it as a different battery which is Nim of nickel hydride.
Don’t do that. Just try a discharge to 3.3v per cell and then balance charge. If that doesn’t work the battery is bad.