Lipo care

[VinCopter]

I like to share a possible disaster.

Crashed my Mustang last Saturday, yeh big deal … HARD .
The 3mm prop adaptor shaft snap clean off, whole motor mount collapsed, whole nose from canopy left 30 % the rest in pieces, wing mounts broke off …

OK, the important thing starts here.

Initial inspections after the crash at the field shows that one side of the lipo pack was dented and the pack was warm. The temperature was like normal. But later when at home while unpacking the stuff, the pack was hot, can’t hold for long. So I take some measurements, the voltage on the centre cell was dropping as I was looking at the readings. So I put it in the Lipo guard bag to let it cools off.

Lucky I check! Or maybe I’m lucky. If it gets hotter unattended, anything can happen.

A few hours later, after it has cool down, take the measurement of the centre cell. 0.24Volts, it’s dead. The other two shows similar readings at around 4V. The centre cell looks physically unharmed, no dents but it dead, there could be an internal shorts.


Lesson learnt
1. Must keep regular check on lipo packs. Especially after crash.
2. You never know what is happening inside the cell.


Take care and fly safe.

[johndyl]

the liposack came in handy :P

[$h@d0w]

Sad to see your Mustang crashed that day. It was flying so well and quiet.

[johndyl]

yep so well setup.. and flying so smoothly......

[VinCopter]

Sad to see your Mustang crashed that day. It was flying so well and quiet.

The Mustang will fly again.

[$h@d0w]

The Mustang will fly again.

[mtyw8888]

Is it alright if per cell is 4.21 - 4.22. I knw it should be maintain at 4.19 - 4.2. Will it do any harm to the batt if is slighly above ...?

[johndyl]

Is it alright if per cell is 4.21 - 4.22. I knw it should be maintain at 4.19 - 4.2. Will it do any harm to the batt if is slighly above ...?

what charger and batts are u using? and how are u measuring the voltage?

my batts never gets charged above 4.2V/cell

t15 abt 4.16/4.17
imax abt 4.17/4.18
triton abt 4.15/4.16
prolux abt 4.18/4.19

voltages are checked right after charging with a multimeter..

BTW someone mentioned b4 that they felt the batts were "fuller" after being charged by the cheapo prolux, i guess they were right by the numbers measured

[mtyw8888]

Im using DN charger...Now my problem slove...even if i charge 1 x 2s or 2x 2s together they still reached at 4.19 - 4.2...

What u stated yr charger is better then mine but why cant yr batt go up to 4.19 - 4.2?

i check my battery with muiltmeter after i charge them...

[viper1990]

Hi i got another question quite similar, i accidentally dropped my lipo on the floor about 1 meter high and make a small tiny dent (picture). I quickly measure the voltage but seems normal, an hour later it dropped by 0.01V, the next another 0.01V, After the whole day, that particular cell dropped 0.2V. It seems that the lipo is actually discharging itself!

Ok so my question is, it is still usable? i only use it less then 3 times

And is there anyway to save that lipo from ''self-discharging?''

(the dent is on the left side,and only 1 cell is discharging , the other is fine)

[johndyl]

Im using DN charger...Now my problem slove...even if i charge 1 x 2s or 2x 2s together they still reached at 4.19 - 4.2...

What u stated yr charger is better then mine but why cant yr batt go up to 4.19 - 4.2?

i check my battery with muiltmeter after i charge them...

maybe diff mutimeter?

even when charging, my charger output for 3s is only 12.56-12.58 as measured by multimeter

[johndyl]

Hi i got another question quite similar, i accidentally dropped my lipo on the floor about 1 meter high and make a small tiny dent (picture). I quickly measure the voltage but seems normal, an hour later it dropped by 0.01V, the next another 0.01V, After the whole day, that particular cell dropped 0.2V. It seems that the lipo is actually discharging itself!

Ok so my question is, it is still usable? i only use it less then 3 times

And is there anyway to save that lipo from ''self-discharging?''

(the dent is on the left side,and only 1 cell is discharging , the other is fine)

bro lipo self discharging is normal.. some of my cheaper batts discharge by .08V after 6hrs

if it bloats, thats another story..

btw all batts self discharge

[viper1990]

no bloating, just selfdischarging.., if thats fine, in that case..i'm less worried thought that my battery spoilt. But another thing, one cell discharged faster then the other. its that normal?

[johndyl]

no bloating, just selfdischarging.., if thats fine, in that case..i'm less worried thought that my battery spoilt. But another thing, one cell discharged faster then the other. its that normal?

probably means one cell is weaker than the others. what brand is the batt? if it is a gd one and bought not too long ago, u can bring back to change i think

[johndyl]

btw when u say different, how much? if by .02v it is ok