Charge dilema

[slippy]

Hi all. I recently put on balance charge my turnigy nanotech 4200mah 2s on my Imax b6 and set the max mah at 4200 and the charger stopped when it reached it. Problem is both cells were not balance charged and both just under 4v. So is it ok to put the mah setting higher to achieve full voltage charge as in my experience with ni-mh is that the mah is usually less than spec.

Dave.

[Dr Fly]

Hi,

As you say, It sounds like you have set the safety limit on your charger to the capacity level of the battery. I have had a quick look at the manual for your charger and it looks like the safety limit is a feature that is mostly used for NiCd/MiMH batteries and is not strictly needed for LiPo charging. It calculates the total energy applied to a battery and then stops. The total energy supplied figure will not account for inefficiencies in the wireing or lost energy due to heat etc which can be 10%-25%. so it sounds reasonable that the charger will cut off around 4v per cell.

Whilst there is no reason why you cant use the safety limit for for LiPo Cells, it is kind of redundant as you charger will also cut off at the LiPo max cell voltage of 4.2v per cell, which is conventional way of detecting when your battery is fully charged.

I would recommend either increasing the energy cut off number, or disabling the feature altogether. the most important thing is that you never exceed 4.2v per cell. which the LiPo charge function on your charger is already programed to do.

[slippy]

Thanks Doc. Yes 4.2 is the normal cut off point and the reason I have concern is that the mah cut off has always been on and It still completed balance charge and just thought there may be a fault but now I will just disable or increase it as its ok to do it.

Dave.