Noob Charger Question

[Sqwidge]

I know that if your batterys are not quite up to scratch you can cycle them on your charger to try and recover them, my e-flite li-po seems to be a bit pants, by cycle does that mean discharge them (discharge goes to 9v on my charger and its not changeable) then re-charging them?

Would i also use normal charge or balance charge as i have been using balance on my li-po's as i thought this was best.

I assume the other 'normal' charge would be for just charging but it wouldnt be balanced ending up with more power in one cell than another, but i cant see why you would do this.

[marktigere1]

Cycling normally applies to NiMH and NiCD batteries not Lipo's.

Sounds as though your Lipo might be on its way out.

Always balance charge your Lipo's in my book though.

Cheers

Mark

[cjcj1949]

That's for NiCds. Lipos have a limited life. Some people have been able to improve batteries on chargers like the CellPro. The manufacturers say that once your cells are down to 80% capacity that they shouldn't be used any more. Original batteries that come with the Blade 400 or the TS3D are known to be not very good.

Chris

[Guest]

Always balance charge your Lipo's in my book though.

My LHS said it is not essential to balance them each time, instead you can do it once every 10 charges and its ok...was he right in telling me this?

[marktigere1]

My LHS said it is not essential to balance them each time, instead you can do it once every 10 charges and its ok...was he right in telling me this?

In my opinion I don't think so.

Since I have had a Cellpro charger, which shows the individual cell voltage, I would say all of my Lipo's have been a small amount out after each flight.

Hence I balance charge them.

If you have better batteries then I would guess the LHS advice is correct.

Cheers

Mark

[cjcj1949]

My LHS said it is not essential to balance them each time, instead you can do it once every 10 charges and its ok...was he right in telling me this?

Yes and no. I rarely do balanced charges now as on my charger they take longer. I do check the voltages of each cell before charging and I have found that differences when the cells are discharged get smaller as the cells get charged (unbalanced). The cells only really need balancing if you want the last 1% of performance or if they are getting old,as the real point of balancing is safety. If you only look at the overall voltage then a bad cell would cause a good cell to overcharge and if bad enough could cause a fire. The 8.4V overall is normally 4.2+4.2 but if one cell is really bad it could be 3.4+5.0 which would be dangerous. People who used lipos before balancing have said that they never had any problems.

Chris

[Sqwidge]

I ALWAYS balance my li-po's but just wondered if discharging them then recharging them after a 15 min cooling period would recover it, im glad i bought another lipo the other day though if this one is dying, looks like i will be having another on Sunday.

I know that you have to 'break' a lipo in when its new but when 'broken' what ideal flight time i was told around 4-6 mins

[marktigere1]

People who used lipos before balancing have said that they never had any problems.

True, but they also didn't last as long

[cjcj1949]

True, but they also didn't last as long

Was that put down to balancing or lipos getting better?

I'm not against balancing by the way, it's just slower and not necessary unless your cells are out of balance.

Chris

[marktigere1]

I would say it was down to better balancing chargers.

The Cellpro for example has kept a couple of my older Lipo's going by performing amazing balancing where as my old Lipo balancer could not cope with them and just rejected the bad Lipo's.

So I guess its a combination of good Lipo's and more sophisticated chargers.

Cheers

Mark

[unwind-protect]

I'm not against balancing by the way, it's just slower and not necessary unless your cells are out of balance.

Not my experience. I have a Cellpro 4S and generic BC-6 charger. To save time I decided to try to charge one battery on the 4S, and start charging another on the BC-6 (which, as I don't have an adapter for, I had to do an unbalanced charge). The plan was to stop the BC-6 at around 4V/cell, and then put that battery on the 4S to finalize the charge.

I have no reason to believe the cells were massively unbalanced at the start, but even at <1C charge rate one cell ended up well over 4.2V (and the others well under 4V). I was shocked, and won't be trying that again! I think these were new(ish) batteries, because I remember being sad that I'd probably wrecked the pack (it seems fine, btw).

YMMV, as they say.