Lipo Batt Life Span?

[ericwardle24]

I bought an Overlander Sport 11.1v 3350mAh 25C Lipo in Feb 2013 from Modelsport 

 

Charged it up last weekend took ages for the last cell to reach full capacity.

 

When I ran it all seemed fine for the first 2 mins then the car got sluggish lacking power like the batt was draining real fast

 

Aren't Lipo batteries supposed to last longer than this?

 

Btw it has always been balance charged too

 

[stretch]

have you been storing them at the correct voltage?

[ericwardle24]

I would say so. My auto lipo cut off volt/cell is 3.5V 

[Oh How Original]

I would say so. My auto lipo cut off volt/cell is 3.5V 

 

If it's been stored at 3.5v per cell then no wonder it's buggered.

The correct storage voltage is 3.6-3.8v per cell.

I generally stick to closer to the 3.8 mark.

[ericwardle24]

I measured the voltages per cell after the run and reveals;

 

3.75V Cell 1

 

3.75V Cell 2

 

0.25V Cell 3

 

I've always assumed that that when the batt cuts out it was at 3.5V but thats not the case if the cells are reading 3.75V each from the the voltmeter.

[R46]

you have a bad cell in pack 0.25v which is why took longer to charge & had ultra short run.

Edited October 26, 2013 by R46

[Oh How Original]

Also, your LVC may be set to cut off at 3.5v and it shows 3.75v.

When the battery is under load it'll drop lower than when stationary, so it could be at 3.75v each but it still may cut off if you hold the throttle open full under load.

If that makes sense.

[stretch]

I would say so. My auto lipo cut off volt/cell is 3.5V

does your charger have a storage function? storing at lvc level wont do them any good.

[suicideneil]

Yeah, what voltage were you storing them at?

 

And yeah, you have a dead cell- warranty time....

[ericwardle24]

I would say 3.75V - 3.6V for each cell. I always read the voltage after runs reading around 10.9V so they've been stored at that for a week until it got the balance charge.

 

One of the cells on the pack has swelled up and ripped the plastic and also torn the metal strip feeding one of the cells.

 

Rang Modelsport today turns out 'if the battery was in acceptable condition from when I first got it they can't do anything under warranty even if it's lasted 9-10 month' 

Edited October 28, 2013 by ericwardle24

[mydoddy69]

Sounds about right to me, lipos are not under the usual warranty and most places inform you of this before hand or ask you to read the terms and conditions .. Check them run them and that's the warranty stage about over and that's pretty much anywhere.. sometimes you may get lucky if there like a few charger's old

 

After you use them and when the truck cuts out you still need to really come home and put them back on charge to get them at storage.. It's not really any good storing them at the trucks cut off ..

 

You can remove the dead cell and keep it as a 2 cell but not something i would recommend to someone with out them having the knowledge to do so and a good level of soldering skills