I was directed over here from another forum for possible help, so greetings!
I am attempting to charge Lithium Ion cells with my Accucel 6 charger and having some issues.
I got 2 sets of brand new cells, 1 set of AA size 1200 mah (GTL brand) unprotected, and 1 set of Trustfire blue 2500mah protected.
When I try to charge a single cell at .5a in either Lion or Lipo mode, the voltage goes right up to 4.2 and it stops charging after a few minutes. On the multimeter the voltage is no where near 4.2.
Similarly, when I try to discharge at .5a, the voltage drops very quickly and the readings seem erratic, and I only get a few minutes discharge (shows around 80ma) before it hits 3.0v.
Any idea what might be the problem? Am I doing it wrong?
Welcome to BLF. There are some really smart battery/charger guys around here, shadowww is one of them. I’m sure they will get you squared away quickly.
Are these the only li-ion batteries you have? It seems unlikely you would get 4 crappy batteries at once, but it could happen. The batteries you're using don't have the best reputation either. No way you'll get 1200mAh out of a 14500 so they are lying up front.
If you have any NiMH batteries you could try charging or discharging them on the appropriate setting just to see if the charger is working in general.
as you can see I'm using aligator clips direct from the charger with strong magnets connecting to the battery poles. i have a multimeter also connected as a second voltage readout with the probes in the aligator clips.
both nimh and lipo batteries charge perfectly using this charger and have done for as long as i've had it.
the discharge cycle you see running is from a "full" charge.
Oh that isn't a trustfire, thats one of the AA size GTL cells. im running it through a few charge/discharge cycles and the capacity seems to be getting better. it is really odd though that the voltage jumps to 4.2 within a couple of seconds of starting a charge cycle, but it keeps charging and never goes over 4.2, and that the voltage drop is so quick on discharge. could it be something with the algorithm of the charger?
I moved the magnets so that they are clamped in the aligator clips and touching the cells with the short ends and that seems to help. the cells are taking a higher charge/discharge rate now. the capacity on these cheap little buggers seems to be around 300mah so far, ugh. Think I should complain to the ebay seller. Of course it would probably cost me 1.60 or so to send them back and I only paid 3.00.
hopefully the trustfire cells will be better.
!on another note!
the trustfire's I got were not the same as in the auction. they advertised Genuine Trustfire 2500mah, with the grey unprotected cells pictured. what I got instead were the protected blue cells.
i need to wire these up in series. will the pcb protection in the blue cells prevent that? any way to circumvent?
Sounds like horrible batteries. You can tell the seller they aren't measuring up to anywhere near the advertised capacity and see what they say. Really cheap generic lithium-ion batteries from eBay are never a good idea.
yes, these are abysmal. it seems that they also only discharge down to 3v at a very low current (.1-.2a). with a stronger discharge (say .5a) the voltage drops very quickly and stops the charge at 3v but the actual voltage after the charger cuts off is around 3.8. learning new things about these li-ions.
i'm still wondering if I can use the pcb protected trustfires in series. I hear both answers.
never use protected because the pcbs interfere with the charging and discharging in series
always use protected because each cell must be monitored in series
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johnwohl!