Originally Posted by
Dave H
The reason you sometimes see higher than 1 parallel is just packaging. If you don't have cells just the right size to fill a battery compartment, but have cells that are right at half the desired size, bingo just double them up in parallel.
No worry about balancing, the cells in parallel will continuously balance with each other. All the time whether being used or not (within a single assembled pack anyway). Normal balancing still recommended for the series portion.
The only concern is when assembling the pack, should have all the cells at the same voltage. Any difference, and the balancing will happen very quickly, could cause some high currents.
It would seem to me that placing cells in parallel would prevent individual cell balancing. Let's say you have two cells in parallel -- you can only treat it as one cell. At that point, if one of those cells gets slightly off, you cannot correct it without pushing the other cell the wrong direction. Let's say you have two cells in parallel, one at 100%, the other at 95%. Not only can the charger not tell which cell is which, if you were to somehow determine you needed to drop one down, it would take them both down because they are connected together in parallel.
See what I'm saying?
Seems to me that it would always be preferable to have better single cells in series than to have cells in parallel at all.