They were $5.99 a month or so ago. I was looking at them until the Target/Duraloop deal came along. For $9.99, you're probably better off elsewhere.
In the charging charts for the 1900 mAh Eneloops, at 1A charge, it reaches about 1.57V: Test of Eneloop AA HR-3UTGB 1900mAh (White)
I have seen more than 1.5V when measured right after taking it off the charger. If the voltage gets over 1.6, something strange might be going on.
The i4 seems to charge less quickly when all 4 slots are filled (looks like about half as fast as it’s basically alternating slots): Review of Charger SysMax/NiteCore i4 V2 . So that could explain the long charge time.
Charge time also depends on charge efficiency, probably also related to internal resistance. An older cell recently took over 5 hours at 700 mA, even though the claimed capacity is only 1700mAh. It is a really old and bad cell that I was just using for some testing though.
Yes, the i4 has 2 channels, each connected to 2 slots. 2 cells in different channels charge at 750ma, 2 cells in the same channel charge at 375ma.
As far as the ‘only charge in multiples with nimh AAA’
Does the same go for the i2? I’m thinking about getting some AA/AAA Eneloop to hopefully save some money on batteries in the long run.
My budget ebay $5 charger which has been in use for like 1 year (day in day out) takes 12 hours to charge up fully depleted eneloops be it 1 or 4 (I guess independent channels or something)
Has some sort of termination/indication and the cells are not even warm when charged. In fact, they are more tending towards cool than warm. Never had a problem! So glad my i4 charger from fasttech never came and I got a refund!
No, the i2 has 2 channels for the 2 slots, 500ma. each.
I’ve been charging my AA & AAA Eneloops with my i4 and yes they do get warmer than they do with the Sanyo charger but nothing that I would consider to be alarming. I do charge the AAAs on the same channel with another battery that will take LONGER to charge than the AAAs so that the AAAs terminate charging first.
However, I appears that Eneloops can take a relatively fast charge. The AAA datasheet says that they can be charged at up to 800 mA, whereas the i4 only puts out 750mA max. So… you may decrease their useful life by charging at 750mA but the cell should not be damaged. Also, the termination on the i4 is not ideal for NiMH but besides anecdotal reports of “warm batteries” I haven’t heard of any actual damage to batteries. NiMH can handle a bit of low-level trickle charge.
Link: http://us.sanyo.com/dynamic/product/Downloads/HR-4UTGA-2010-47828277.pdf
(also take a look at the charging voltage curve)