RC-Monster Forums - View Single Post - Investigation ...6s1p or 4s2p, neu, cc neu...

MrMin · 03.04.2009, 06:25 PM

Well if you had two connectors then maybe it would help a *tiny*, *tiny* bit, but redundancy is always better..in case..you flip your batteries out while you are running... ..then..it might well be time to say farewell to your esc.

Back to 4s 6s etc...

I measured each cell in a 5s battery(junk test battery) and got 20,30,20,25,21mOhms... per cell. This means the total resistance is about 0.12 Ohms... Not good.
A good 5s battery will be about 0.055 total. Of course they are all in series.
A good pack will be:
6s=3s x 2= (3x (0.033 x 3) Ohms) + (3x (0.033 x 3) Ohms) = 0.198 Ohms
4s=(4x (0.033 x 4) Ohms) in parrallel = 0.0165 Ohms
This means that 4s should be able to eat more current. (that is if the chemistry can handle it)...But if you offset it against the losses due to low voltage high current&resistance in the wire then you probably can say it is about the same.

When you brake you are dissipating 550joules if 5kg car travelling 40mph. It looks like 180Amps(for 6s, for 4s=even more!) across the battery at FULL brake. This is really a lot - poor battery, because battery is used to 1C, thats 10 amps max ouch.. But then when you accellerate from zero at full power you will draw 180 Amps burst++...

A lot has to do with gearing in the end... How much strain you put on the esc and when....

I've just got both 4s2p and 6s1p(2x3s) setups.

	(#26)
MrMin RC-Monster Carbon Fiber Offline Posts: 57 Join Date: Aug 2008	03.04.2009, 06:25 PM Well if you had two connectors then maybe it would help a tiny, tiny bit, but redundancy is always better..in case..you flip your batteries out while you are running... ..then..it might well be time to say farewell to your esc. Back to 4s 6s etc... I measured each cell in a 5s battery(junk test battery) and got 20,30,20,25,21mOhms... per cell. This means the total resistance is about 0.12 Ohms... Not good. A good 5s battery will be about 0.055 total. Of course they are all in series. A good pack will be: 6s=3s x 2= (3x (0.033 x 3) Ohms) + (3x (0.033 x 3) Ohms) = 0.198 Ohms 4s=(4x (0.033 x 4) Ohms) in parrallel = 0.0165 Ohms This means that 4s should be able to eat more current. (that is if the chemistry can handle it)...But if you offset it against the losses due to low voltage high current&resistance in the wire then you probably can say it is about the same. When you brake you are dissipating 550joules if 5kg car travelling 40mph. It looks like 180Amps(for 6s, for 4s=even more!) across the battery at FULL brake. This is really a lot - poor battery, because battery is used to 1C, thats 10 amps max ouch.. But then when you accellerate from zero at full power you will draw 180 Amps burst++... A lot has to do with gearing in the end... How much strain you put on the esc and when.... I've just got both 4s2p and 6s1p(2x3s) setups.