Need new li-ion charger suggestions

[Hooked on Fenix]

I have an Ultrafire WF 139 li-ion charger that doesn't seem to charge my AW cells longer than a minute or two if at all. All my AW cells are 18650s and 17670s and were purchased this year. They haven't been used much. They have been dead when starting to use them in flashlights. I think I need a better charger as I trust the batteries more than the charger. Any suggestions where I can get a reasonably priced high quality charger that won't fail in the year I bought it?

 

[Unforgiven]

Some of the older WF139 chargers do trickle charge which is not good for Li-Ion cells. If you happen to have one of those models and didn't take the batteries off the charger right away after it indicated a full charge, there is a chance the batteries are no longer any good.

I would recommend the Pila IBC charger.

 

[Hooked on Fenix]

Thanks for the suggestion. I just ordered the Pila charger. I'm pretty sure the problem was the charger. The last 18650 I tried charging in it would charge about a minute, go to trickle charging for a few seconds, then start charging again. The times between charging and trickle charging kept decreasing until it was only a second or two per charging stage. I figured that charging in pulses of a few seconds at a time couldn't be good for the batteries since li-ions have a memory effect. I don't want to ruin my batteries further. I'll discontinue using them until the new charger arrives. I hope that charger didn't seriously ruin those batteries. They're expensive to replace. 2 18650s cost $13 each and 4 17670s cost $11 each for a total of $70. If they are all bad, I'm going back to NiMH batteries or using regular lithiums. I got these lithium ions and lights to use them in because I was tired of seeing dozens of 2500 mA and 2700 mA NiMH batteries going dead prematurely in the last year or two.

 

[Hooked on Fenix]

Unforgiven, you were right about the batteries being bad and the charger messing them up. The new Pila charger refused to charge the 18650 and 17670 cells (only one of each). At least, thanks to your suggestions, I have 4 good cells that won't be ruined and should last. I guess now I'll just have to save up for more cells to replace the bad ones.

 

[mdocod]

Firstly, li-ion doesn't have any memory effect, in fact, memory effect is a myth that has been dragged on and used as a buz word for rechargeable batteries for years. NiCD, NIMH, Li-Ion, none of them have memory effect when used in a consumer application with a consumer charger.

As for your cells. Have you checked the voltage on the cells to see what's going on? Is it possible they are fully charged already? Using loose li-ion cells without owning a volt-meter makes it very difficult to diagnose various behaviors.

It is very possible that a malfunctioning WF-139 could have destroyed the cells. But the question is, in what way? Maybe it charged them WAY WAY up to a severely over-charged state, and you got lucky that they didn't explode, or maybe it has an internal short, and the cells just sat on it and kept discharging in short bursts into the charger as the charger cycled on and off... At this time, it may be impossible to know what actually happened. Oh well..


Eric