problem with lithium polymer Tuarnig '5000mah 40c
 

Hello everyone
I have a problem with lithium polymer Turnigy 5000mah 40c 4 cell
I drive losi 8 with Mamba Monster v3 15181y 1800kv motor
After 10 minutes lift the batteries lose power Nygelsut
Mmbah Munster does not go cut off
I use with Orion Charger
Battery voltage after using balanced cell 15.6v
After loading a 53 min battery voltage 16.8v 1750mah with balanced cells
This problem exists in all my batteries 4 units
I ask what could be the problem?

What speed control are you using?

Castle Creations Mamba Monster v3 Speed Control

What do you have the voltage cut-off set at on ESC and what are you doing while running it? racing, bashing, just running it up and down street at max speed etc

I drive in an organized track racing,
and cut off 3.7v per cell

I'm not sure I understand your question - is it that you're no getting enough run time? The 3.7v/cell auto lipo cutoff is a little high, I run 3.4v/cell in mine and that lets me approach 80% of lipo capacity before the lvc starts.

The cutoff is not a hard one, that power loss at 10min is prob the cutoff. Try using a lower lvc. What you want to do with lipo is have a cutoff that lets you withdraw no more than 80% of the lipo capacity (4000mah for a 5000mah lipo) and not have the resting voltage drop lower that 3.7v/cell.

What I mean is after about 10 minutes until the battery is running low to significantly drive very slow
not arrested by the cut off.
Battery voltage 15.6v after the ride.
A similar situation happened to me with the other batteries and four in number.
I want to ask what is due the problem?
And what can be checked not happen again with new batteries?

First thing I would do is lower the cut-off and see if that helps at all. It could be the cells are unbalancing while discharging..

lvc 3.2

Thanks for your answer but I tried to cut off the past and it did not help
Balanced cells after loading and after discharge (drive)
cell 1 : 3.89v cell 2: 3.9v cell 3: 3.89v cell 4: 3.89v

What speed do you have the car geared for ?

Are the motor or ESC getting hot ?

Turn off the lipo cutoff and see what happens

Cheers

Did you try programing a lower cut-off? If you program a lower cut-off and the cells are still dumping at that voltage you're going to need to talk to the manufacturer as it may be a battery defect..

Only other thing I can think of is temperature.. Have you checked temps on your motor an esc after the batteries dump? If they are too high it could be the heat causing the motor to loose power or the esc to do a safety shut-off..

Also, after the cells dump, see what happens if you let everything cool off and you plug them back in. Just hold the car in the air and see if it will give you normal power..

16 spur 45 pinion differential front and rear 13/43 the car losi 8
motor & esc not hot after drive 55 degrees

The MMM lvc is not a hard cutoff, the better the lipos, the softer the cutoff.



Castle was asked about the MMM cutting off early probs and this was their reply -

"After a cut off, if you go to off throttle and leave it there, and the ESC flashes green and yellow the ESC has hit Low Voltage Cut Off (LVC). It this happens prematurely the battery pack cannot maintain voltage under the load of the motor. You will need better batteries."