Review of USB battery box 6x18650 Qidian

6 months will drain about 0.055*24*31*6 -> 245mAh

Even with only one battery in it, it would not be a problem.

Well after about 8 months of light to no use, my power bank has developed a charging problem. USB output still functions normally, but it only charges the internal batteries to 3.85V, then the 80% LED stops flashing. Charging intitally stopped at the 60% mark and I had to reconnect the charging cable several times before it attempted to charge more, but this doesn’t work once the batteries reach 3.85V. It seems to do this regardless of whether there’s 1 or 6 cells loaded. These are new laptop pack pull LG 2200 mAh cells which have only been used in this power bank. The cells are charging / testing without any issue in my Opus, so they don’t seem to be the issue. I may have to poke around to see if there’s an obvious failed SMD resistor or some other component like the poster with the LED failure.

KuoH

Nice thanks!!

Looks like they have a 5X version that can charge thru a micro USB connector as well

http://www.fasttech.com/product/1457403

I have their 4-cell box, which has a digital display including percentage of charge: http://img.fasttechcdn.com/134/1341600/1341600-13.jpg

I’m wondering how reliable that is — thinking about using it to discharge cells down to 40 percent for storage purposes.

I’ll be trying it, but curious if anyone has done that and checked results (or has another recommended way to take batches of cells down to 40 percent for storage time)

I use my hobby charger to discharge my batteries down to a storage charge. It seems to me that one could hook up a number in parallel and then discharge them all down to 3.7v - 3.8v. I parallel charge cells up to 4.2v so it seems to me that discharging them in parallel should work just as well.

Does it delivers 4amps on the USB-Outputs or on the DC connector only?
Has anyone checked how long it could provide such currents?

Can it be used as UPS ?

There is a new version but with led display that fails to be usedas ups. I think that it is a common problem with all from the same style/manufacturer