I have finally ordered my first pair of Lithium Polymer cells: two 3s (11.1v) 1800mAh HD packs from Dymond.

After spending time looking through these threads I've not directly seen what I'm looking for -- although I'm sure it's in here...somewhere. But my eyes just got very tired of looking. So maybe someone could simply answer me here.

My intention is to use a parallel connector and make a 3s2p pack of 3600mAh capacity -- and, for my purpose, it will always be that way. The reason I bought two packs instead of one preassembled 3s2p pack is because I only plan to use it a handful of times for testing purposes and then sell the packs individually. And the prearranged customers in my club want just 3s1p packs for their pylon racing parkflyer models. So buying a pack already made up as 3s2p and then disassembling it would not necessarily be wise.

Balancing these two packs? Could be done. Although I assume it would have to be before they're made up as 3s2p. So what steps do I need to be aware of here charging packs in parallel; and isn't a 3s2p simply two 2s packs soldered in parallel? Is there such a big difference between using a parallel connector and simply soldering the packs together?

James Frolik

The salient poit about charging multiple cells packs or anything is that they have to be matched charge wise before you start, and kept matched.

If you paralell them straight away, then the voltages will equalise wihout one pack burning up charging the other, and it is, as you say, merely a process of charging one big pack after that.

However when making up parallel packs, I prefer to buy the cells and make my own, and start by paralleling cells before putting them in series.

Some slight theoretical advantges in terms of balance that way.

And no temptaion to split them and use them separately then recombine them in a different state of charge/lifetime etc.

But o reason what tyou are sugesting will not wortk fine.

But how do you rig up the charger? Which pack do you plug the balancer into? Do you wire the balance leads together into a 6s configuration? Do try to tell your charger to balance a 6s pack while charging a 3s pack? I don't think it is wise or practical. I know NiCads won't charge in parallel. There are many warnings about doing it with NiCads.

Kip

https://www.rcgroups.com/forums/showthread.php?t=932319

I'm new to this Lipo thing and have started with 2 sets of 3 Lipo packs that have a P designation, as in: 1300mAh 2S1P 20C 7.4v and 1800mAh 3S1P 20C 11.1v.

My understanding is that within a pack with this designation 2 or more of the cells are connected in parallel.

Is this a pack that should NOT be charged on a parallel charging board; or, is it no different, other than the same cautions?

Thanks

Answered here

https://www.rcgroups.com/forums/show....php?t=1422515