Okay so I have an Imax B6AC charger and the plan was to cycle through my batteries thats been sitting over the winter.
Anyways so I start discharging my glowdriver battery and I got absolutely nothing out of it. Okay fine I think and set it on charge. But I only get about 200 mAh into it before its finished. I discharge it again and get like 700 out of it :S
I do repeat that a few times, the last time I put it on charge it went up to over 4k and still wasnt finished. The battery got really hot so I pulled it off and went to bed. I put it on discharge again and again only got like 700 out of it. The funny thing is that after it had discharged, I tried it on a loose glowplug and it still had charge, I even left it there for a while and it was glowing perfectly.
I thought the battery must be busted so I thought Ill try with a starter battery.
These are 2 7.2 volt Nimh cells with 3000 mAh in each.
First I charge it but I only get around 720 mAh into it but I hadnt discharged it first so I thought it still had some charge.
I then discharge it and get almost exactly 3k out of it. Which is fine. Put it on charge again, and this time I only get 140 mAh into it
Now I put it on charge again directly after that and its on 260 now and keeps going, well see when it thinks its finished.

So whats going on? Are all the batteries busted or is the charger broken, cause its only about a year old.

Yea so now it finished charging my 7.2 volt 3000 mAh starter battery. I got 3500 mAh in it and its very hot and it looks like its leaked batteryacid cause its all white in one end.

Im not even sure Id dare letting that thing charge my lipos

Put another battery in it now and it wouldnt discharge anything at all. Put it on charge now lets see if the thing explodes or not.

Really this is becoming frustrating quickly.
This charger has a mind of its own, its like it just charges and discharges whatever it feels like at the time. The weird thing is that it worked perfectly the last time I used it last fall.

the one pack is "Venting" and is probably shot. It's just for a starter so might not be a big issue. What is your cut-off voltage set at? I run mine at 3mV per cell or 18mV per 6-cell pack. You don't want it any higher than 20mV per pack or you could run into over-heating issues especially when the packs have been sitting for a while. This is a fairly low cut-off for peak detection but it prevents many of those problems... I find I get get back my capacity after a 3 cycles.(Except for the batteries I've neglected) Best to store the batteries at 55% to 80% capacity for NiMH and your SUPPOSED to cycle them every month if possible, but I personally am not that dilligent and have sacrificed some voltage and capacity because of it. If this doesn't solve your problem you might try someone elses charger and see what happens.

When you've let NiMhs sit a long time, you usually get better results with a 1/20 - 1/10C initial charge before you start trying to cycle them to get the mah back up. Don't discharge at more than 1C.


Def check your peak setting, your charger may not be able to go below 5mv/cell - a lot of these type chargers have a 5mv/cell as their minimum. You'll have to watch the temps, you shouldn't let them get hotter than 120-125F. I use a temp gun when charging and if mine get too hot, I pull them off the charger, let them cool and re-start the charge to get them topped off.

Well I actualy charged another battery I had, discharged and charged and it worked fine. So the other two batteries must be shot.
Its just weird how it behaved with the other two batteries.