batteries

[martnslater]

hi all , got a prodigy charger been to charge one of my batteries and it just beeps and says low voltage, its a 1800 mah lipo does it mean my battery is naff or is there a way i can charge it up .
thanks, martyn.

[Biggles]

are you sure it's not input voltage that is low????

When you connect it all up press and hold the left hand button it will tell you your input voltage*.



*3dbasher showed me this

[martnslater]

yes it the currect voltage

[Thomas]

If you let a LiPo drop below 9 volts per cell then a LiPo charger will have a problem with it and not charge it.

You need to get the voltage up over 3v per cell, the way to do it is set the charger to NiCad and bring it up to say 10v on a 3S pack - WHILE KEEPING AN EYE ON IT, it will only take a few seconds but once it's up then you go back to LiPo mode.

[martnslater]

so its possible to restore the cells

[Ade_Law]

if its saying output voltage low then you either have the prodigy set incorrectly or the battery is naff.

i have heard of people bringing batteries back to life by sticking them into nicad mode and charging at a low current watching the voltage comes up. once it gets to 3v/cell you can then charge it normally. do not leave unattended tho. when charging in nicad stop when you get to 3v, and definitly dont let it get over 4v/cell

Ade

[martnslater]

cheers ade, done what's been advised, and all seems ok but will the battery be ok like before, ie flying time. i wa getting about 15 mins will this be affected

[Thomas]

so its possible to restore the cells

A ballancer is a good idea, other wise you can charge each cell on it's own by using the ballance connector, just make a lead up using needles or pins - you do need to know where to stick them though - on an FP pack, if the wires were numbered 1 2 3 and 4 (1 being black) you start with 1 and 2, then 2 and 3, then 3 and 4.

I used to ballance my Align 6S pack like that.

[Smoothound]

cheers ade, done what's been advised, and all seems ok but will the battery be ok like before, ie flying time. i wa getting about 15 mins will this be affected

I have an old 1320 TP lipo that spent 2 months up a tree(don't ask ) and when I got it down it was showing 0v. Just as an exercise I did the NiCd trick and it now flies my Banchee fine and in fact better than a new cheaper pack that I bought to replace it so go figure

[moyesboy]

The cellpro4s charger (from aurorra.co.uk and revolution models) is a dedicated lipo balance charger that has an automatic restore function if it finds a cell between 0.5v and 2.7v.

The charger stops charging the other cells until it has got that one cell back up to a reasonable voltage. Its handled automatically.
I suggest this is the safest way to restore the pack. The chargeris a good investment if you use packs up to 4 cells, or find a nearby friend who has one.

I'm very pleased with the way my cellpro4 works. But I never used the restore function yet.

If you are using a multi function charger to try to restore your pack I strongly suggest you connect to only the effected cell via the balance connector and charge the single cell. This avoids the wrong stylecharging going through the other cells. The good cells could already be quite highly charged and go over volts if you series charge.