I've seen enough positive reports (thanks to HKJ, selfbuilt and scaru) and have ordered this charger. To this point I've been using the unimpresssive wf139 which terminates voltage between 4.12-4.15 (and basically stopped working a couple of weeks ago).
I think $25 is a really good deal for a solid 4 bay charger. I also ordered my 1st 3100 mah 18650 battery (eagletac) as I've been using 2400 mah batteries for over a year. I'm excited to get the additional runtime in my favorite single cell light.
The logging is with a high precision DMM and yes it terminated at a bit above 4.2 volt, is is between 2.212 and 4.215. This value will vary between individual copies of the charger.
The one major downside of these units is the stiffness of the spring negative arm. I've done finger nails trying to get these apart and get a battery in. I've heard some 18650s are coming out with a foil like bottom instead of a metal plate. I'd steer these away from the i4. They could, if your not careful, wreak the foil.
So can someone clearly explain what it going on with charge currents and slots? Lithium-Ion for example (although it seems nearly identical for NiMh except for voltage). Seems from the graph that it's charging at 750mA (until end of charge - just ignore the end for my explanation). Is this 750mA per each of 4 slots? In other words with all 4 slots loaded each cell gets 750mA charge rate? Or (as it sounds to me) that 750mA gets split in half and divided between the channels (channel 1 being slots 1&3 and channel 2 being slots 2&4 - so with 4 cells loaded, they'd each be charging at 375mA? So if I'd want to charge two cells at 750mA I'd have to load a cell into slot 1 (channel 1) and then use slot 2 or 4 so I have the second cell on channel 2? If I'd load 3 cells in using slots 1,2,&3 than the cells in slots 1&3 will charge at 375mA and the cell in slot 2 will charge at 750mA? Am I correct in my understanding?
This does sound like a nice universal charger. I only wish the charge rate were higher for 26650 cells.
The green text is basically correct. Basically because the current is still 750mA, but only half the time, with LiIon this makes the charge time slightly longer, compared to a real 375 mA charger.
It is not the fastest charger around, if you look at the text under the chart with 4 batteries, it says 11 hours.
Its a pitty that DD cant offer any group buys anymore, except for regular coupon coudes
HKJ, thank you very much for clarifications!
Tempted to buy this charger even tho I dont use Li batteries at all, but seeing this priced at less than 25$ is rather big temptation to pull the trigger on universal charger :D!
One question to add, sorry for spamming this thread
Can I add some conductive piece of metal between + on charger and + on cell and charge D sized batteries?
Will it stop when they are full at for example 8000mAh or 10'000mAh or will it stop at 5000mAh because that is the currently highest 26650 capacity available and charger might not recognise higher cell capacity as safe?
So, basically, it charges at 750mA current in all slots, only thing worth noting is that its charging in pulses and not constantly? Or does it really drops the output to real 350mA in those two other slots and it has nothing to do with pulse charging and its real 2x750mA and 2x350mA=4slots?
All this got me confused somehow, exactly when it seemed perfectly clear :D!