When using 6 cell packs to make 12 cell..........?

[Gremlin]

Hi Guys, just moving to 12 cell after a long time flying, I have 6 cell 5000mah packs that I have been using in my 550, the packs have done similar amount of flights. Are they ok to pair up and use in my 12 cell bird and continue using in my 6 cell setup when I like? All packs will be charged individually as 6 cell.

Just heard that you must buy new and keep the packs paired. Not fully sure of the reasoning to this.

Any advice would be great!


Dean.

[Flyingzook]

As long as they are roughly the same age/condition and are the same C rating they should work.

[davehour]

Hi,

In your case, you should be fine.

You can mix packs of different capacities and age as long as their cells are fine. The real problems come when packs that don't track well while charging, are mixed. When I say track, I mean how the cells balancing track as they are charged. Small differences are fine, e.g. some cell that reach 4.20 while some others are 4.18 or 4.19, but any difference greater than 0.3V, is not good.

From time to time, balance charge each pack individually to keep the balance tracking up to its best, and make sure none of its cells are going bad. And it's a good practice to verify the cell balancing state of each pack prior to parallel charge them. When packs are connected in parallel , it's not possible to pinpoint a bad cell or incorrect balance condition.

I would also advise you to use a fused parallel board. This reduce the danger of shorts and fires if one cell goes bad while charging, or if you make an incorrect connection. You will be connecting many connectors and errors can happen. In addition, after you follow the charger recommended procedure to connect the first pack, connect the other packs main leads first, and last the rest of the balance connectors. This help equalize the packs in the case there is a noticeable difference in charging and balance state between them.

David

[Gremlin]

Thanks guys

this is what I thought, just being careful as you have to in this game!




Dean.

[Gremlin]

is it best to parallel charge or best to charge each 6 cell separately?

pros/cons?

[davehour]

Originally Posted by Gremlin

is it best to parallel charge or best to charge each 6 cell separately?

pros/cons?

Best to parallel charge, as long as you do it correctly and with the proper charge capacity on hand. I've been parallel charging for a long time and can't mention a reason why I would not keep doing it. It does require more care and attention to avoid problems.

[Gremlin]

ok thanks for advice