Balance Charge taking a long time

[cutting42]

Hi All

I have a Core UAC50 and a selection of 2S Lipos from 4500 mah to 6800 mah in both saddle and stick pack form for my and my sons cars.

I always balance charge and in the case of the stick packs (IP) have done so from new. The saddle packs are Orion 90c carbons and Orion 50c Carbons second hand from users who claim to have balance charged from new.

Recently the balance change for half of the packs has been taking the full 90 minutes (timer cutoff) but seems to have reached capacity much earlier.

Does anyone have any suggestions? The batteries still work great and I typically only take 1500-2000mah out of a pack (2 heats) and do not top up.

Is this a charger problem? Are the batteries damaged? Should I extend the time cutoff so the charger finishes correctly?

[metalmickey0]

I get that too with some of my cells. They takes aaaaages to charge. So i`ve upped my timer cut-off to 150mins. That seems to allow them to balance fully.

[RogerM]

I've had this problem in the past and it has ALWAYS been down to the balance cable breaking down. Each time I've put a new balance loom on (the 3 wires between the board and the cells not the board itself) the problem has been cured.

Just to be certain it is worth taking the saddle packs and charging them as individual 1s packs as opposed to the 2s saddle and make sure the charge shuts off ok like that.
That will prove it's not the charger and that the cells are ok too (plus bring them back into full balance as both halves of the saddle pair will have been 'fully' charged individually).

Hope that helps.

[cutting42]

Thanks guys that helps.

I have one pack of saddles and one stick pack that still balance charge in about 25 mins so the Charger seems to be working OK at least occasionally.

I will change the balance board/cable to check as well as trying a 1S charge for the saddles.

If that fails I will extend the cutoff and see if that brings the batteries to balance.

[RogerM]

It is normally the cables between board & cells that is at fault, just had to do one myself.

Have you got a mate you could swap components with to make fault finding easier?

You can do the 1s charging trick with sticks too, just connect to 1large & the small port but best to do this with lower current settings.

[cutting42]

Originally Posted by RogerM

It is normally the cables between board & cells that is at fault, just had to do one myself.

Have you got a mate you could swap components with to make fault finding easier?

You can do the 1s charging trick with sticks too, just connect to 1large & the small port but best to do this with lower current settings.

I have a second cable so will try that next. I am racing tonight so will have a chance to recharge tomorrow. Thanks for the pointers.

[Darren Boyle]

Gareth, ideally you should always charge your LIPOs at racing (or just before) and not a long time prior to the meeting (leaving them fully charged) since a full LIPO is most prone to puffing, should ideally be charged in a partial charge status.

Will chat to you more about it tonight at the club...........

[cutting42]

OK Darren, chat later.

I usually charge the day before racing, maybe that is what I have been doing wrong.