Lipo setup

[ajdreher]

I am looking at getting a set of lipo's for my boat (titan 29, 9xl, hydra120). I want to run 4s so these are my options;(i always get series and Parallel confused, so not going to use those terms)

1. two 4s batteries to double the run time

2. two 2s batteries to make a 4s set up

So besides run time, would there be any major difference between these two set ups as far as power and speed. I am looking at getting the max amps lipos, so if I went with the two 2s i would get a couple 5000mah batteries, which would be plenty of run time for a race (and would be cheaper than buying two 4s)

hope you all understand what I am asking, any thoughts?

[Darin Jordan]

OK... You want 4S, or 4 * 3.7V = 14.8V Nominal...

The question seems to be whether you want to parallel the cells or not...

If you buy two 2S packs, you will have to wire them in series (one of the reds of one pack to the black of the other...) to make a 4S from it... (two * 2S = 2 * 7.4V = 14.8V)... If you buy two 2S 5000 mah packs and wire them in series, you'll have a 4S1P setup with 5000 mah...

If you buy two 4S1P packs, you will wire them in PARALLEL (red to red, black to black), which will give you 4S2P, and if they are each a 5000mah pack, you'll have a total of 10,000 mah...

The later setup will cost you about twice as much, but will have twice the runtime... Will also provide more power ultimately as you'll have more current available... and the cells will run cooler; straining less to supply higher current.

Hope this helps...

[ajdreher]

Thanks for the info Darin! That is exactly what I was looking for. So if i'm looking to take care of my investment, going with two 4s batteries in parallel will be easier on my batteries and help them last longer?

[Darin Jordan]

So if i'm looking to take care of my investment, going with two 4s batteries in parallel will be easier on my batteries and help them last longer?

It really depends on how hard your setup pushes them... In something like an SV27... Paralleling wouldn't be a benefit... I'm guessing that your 9XL setup, with the right prop, would work fine on a 1P setup... but it would benefit from having 2P... Everything would run cooler, you'd have more runtime, etc... and YES, the cells would last for more cycles...