Not cutting off that you noted really disturbed me. So I checked mine. (It just never occurred to me to check for this.)
My black unit has the 6316. When using it to charge a device, the 6316 will suck the 18650 all the way down to zero.
My 2 others have the 9635 and cut off discharging the 18650 at about 2.75v - 2.80v. It’s not actually a sharp cutoff but is gradual decline.
So to repeat what others are saying, the units with the 6316 are bad.
The units with the 9635 are good.
Woo, thank you Cfcubed and Dchomak. Very good safety info. Going to check mine right now.
Shoot. I just I should be somewhat happy that I only ordered 1 black one (I think) when I made my 2nd order for a whole bunch for gifts :~ . If I don’t bother to fix that one than maybe I’ll only keep that one for myself and use it sparingly (+ safely.)
In any case, thanks for the good detective work guys! It helps keep oblivious people like me safe with things like this…
OH SNAP! I forgot I have like 3-4 of those little .36” voltmeters just laying around…going to be modding one of mine to monitor the voltage…
I snapped the USB micro connector on a Xtar MC1 3x times…carefully soldered it back down…well last time it came off I got pissed and used a flathead screwdriver and stripped the board…just shoved the components off like a bulldozer, then soldered a pigtail and one of those thin TP4056 boards on it and super glued the base back on…and wouldn’t you know it…works like a champ (broke the daggum spring tonight and said to hell with it…ain’t gonna fix it again…just cut the charger module and chucked the whole thing [I really do like those slider charge holders though…uggh…recovering and will try to mod it with a pen spring or something] {correction, the bottom flexed and the spring jumped off the round holder…I cut off the pigtail in error…DOH!:smiling_imp:
I also built a 4x 1s4P board with the voltage meter on it, I charge 1 battery at a time or ALL 4 out of my SRK (I know better than mix/match different level batteries on a single channel)
I’ll mod one of these little ones and do a full discharge and see where it stops and then do a full charge to see where it stops…I can say the ones that I put the silicon/RTV run more “stable” but like I said, I’m no electronics engineer
I’m waiting on my order of 5 too. And i’ll demand a refund for a those 6316 i get!
Looks like there’s confirmation that the units w/FM6316CE implementation are unsafe for use with unprotected cells, they’ve no low battery voltage cut-off or indication. And as OP/chiefinspectorfinch indicated, and the tight fit backups up, no (few?) protected cells will fit.
chiefinspectorfinch - Please consider amending the first/original post of this thread with this info. I, like others, do not always read review threads to the end & might miss this important info. We also cannot be sure that ordering a white one will always get you a safe/ETA9635 one.
Two ways to tell you’ve an unsafe or FM6316CE one:
1) you don’t have to take it apart & risk what happened to flydiver… Here’s a (crummy) photo of the top side of my unsafe/FM6316CE - compare to equivalent/last pic in first post in this thread (e.g. the black 0 ohm resistor next to soldered spring (likely a cold solder joint BTW)):
!
!
2) a simple run-down test w/DMM & clip leads w/unit charging something that’d use all its power. Of course be VERY careful not to short cell.
IMO not sure you can fault the seller of bad ones if the transaction is good otherwise. He’s likely not the designer, he’s just pushing product. Perhaps informing of this thread / asking for one w/ETA9635 (top side looks like chiefinspectorfinch’s photo) would get you somewhere but I doubt it.
Again best to stick to proven/tested stuff (e.g. see HKJ’s site). But as even tested products can change over time guess sticking w/names/reliable suppliers OR maybe carefully comparing photos of guts is something.
I was alarmed when I read this so I checked my powerbanks and found that one of the yellow banks (I have 10, 2 per color) had 6316. I charged this particular powerbank 4 days ago and placed it aside for future use. When I took the readings, the new unprotected Samsung ICR18650-28A reads 0.96 volts which means that it discharged by itself and drained the cell below safe levels.
Now I’m not sure whether I should recharge this cell but I’m pretty sure I’ll never use this particular powerbank again. Will it be safe if I recharge this drained lithium ion using a NiteCore i2? :~
Well I went ahead and charged the Samsung ICR18650-28A with 0.96 volts using my NiteCore i2 and observed that it reaches 3 bars (full charge) from 1 bar in a few seconds so I immediately removed it from the charger fearing that something bad might occur. 
I took the readings and its now 2.25 volts? :~
Some1 should inform BIC of this fiasco before anyone gets hurt!
With all the crap-chargers and CrapFires they sell, I guess they don’t care.
Seeing Nightbird95’s post I just tried to measure parasitic draw for my unsafe/FM6316CE unit & it’s below resolution on my Fluke 111… But that’s not saying much, it doesn’t resolve low enough. So parasitic draw is another possible problem w/these units.
In doing so I found out how/why these unsafe/FM6316CE ones fail under heavy (current) draw - They don’t appear to limit it. Trying to charge an IPad just now I measured 1.9A draw, about double the 1A limit per FM6316CE datasheet. BTW the datasheet also expounds WRT low parasitic draw (16uA) & protection (incl under-voltage), so guess we’re just looking at horrid/faulty/dangerous implementation.
Guess my IMO above should change - A seller informed of this should refund & cease selling the unsafe/FM6316CE ones.
I also informed the shop where I bought it (eBay Shop from “keyzone”) with a link to there, also to get a refund for the black one that was defective after 5mins.
I would guess that nobody really gets hurt, or rather equally bad for both chips. Only the battery cells will get damaged with the FM6316 because of the discharge issues, but they won’t get shortcircuited or overcharged. At least from the current information we have. Of course both of these chips/designs could still have some other issues. When looking at the poorly detailed datasheets it looks like “anything could happen” ….
// Edit: Ok afterall the datasheet of the FM6316 seems to be actually more detailed than the ETA one, at least what you are showing here and what I found for the ETA. And like you said, maybe poor implementation, wrong current limiting resistor? I will check mine at another time…
0.96v is essentially dead. It doesn’t take much to push them back to a much higher voltage on that steep part of the discharge curve. If you can hook it up to a low volt/low output dumb NiXX charger for about 5-15” then check it again. If it’s up to 3.0v or higher then try the i2 again. Watch it carefully.
If it won’t take the charge > discharge and trash.
If it will > mark it clearly and consider it a ‘wounded’ cell.
If you don’t care for the risk (there is some) you should simply discharge and trash. If you aren’t sure > trash it. Better safe than sorry for a few $$.
Thanx for the tip flydiver. It now has a big red asterisk mark.
I charged it with the i2 (it wont fit the NiMH charger and my other charger is an i4 which has higher output) for several minutes and was in the 2-bar range when I removed it to get the voltage reading - its 4.05 volts. I guess this cell can still be fully charged then.
In the latest AliExpress sale, I ordered 20 of these to give out to people. I ordered the white ones, but if they come with the 6136 chips I will be filing a dispute. Because the implementation of the 6136 is just laughably bad.
I just checked for parasitic drain on the 1, 6316 that I have.
With a fresh cell (4.15V) the drain is 17 uA
But a with a damaged cell (1.92V) the drain is 111 uA.
I also confirmed that the 6316 will attempt to give more than it should . An iPad received over a 1.7A (they need 2.0 ) and a GPS unit for my car got 1.7A. Both are too much for this little unit. Chips started to get hot very quickly.
It could be OK if it was a newer cell and you caught it quick. The older and the longer at very low voltage the more the damage. Damage will first show up as higher resting drain and lower performance under high draw.
That’s what I don’t understand…per a translation of website pertaining to the FM6316CE
If it was working as designed these chips “should” thermal/current limit to 1A and charge the li ion with the correct CC/CV…but alas…it appears that either a bad design or bad components on the board…unknown at this time till someone with ALOT better test equipment can see just what these boards are doing…hmmmm
So far all 4 of my other FM6316CE driven boards are doing what they are supposed to do on charge…all of them give blue on full charge, using one of those .36” voltmeter I get 4.2 on the readout, and on power out they run whatever device just fine and don’t get warm, the one black one however smoked after a few hours (I need to get a USB doctor module)
I am getting one of these for sure…maybe 2 or 3
http://www.dx.com/p/usb-av-usb-power-current-voltage-tester-translucent-blue-silver-235090?r=43033281
Give me something for easy volts/amps diagnostics
BLF review thread
I have a similar type unit, but it is a cree flashlight, with the USB input and output on the tail, where a metal plate rotates.
I’ve used mine to top up various android and windows phones, and it works, but if I were relying on it for charging, I’d probably skip the flashlight, and go for one of the 4 pack cases, that are < $10. Also, makes a great storage bin for charged batteries.
Now if those 3-4 emitter x 4, (Skyway, etc.), had USB chargers on them, those would be very interesting, but the on/off switch makes those lights useless for my needs, and rather large diameter wise.
I bought one of these http://www.ebay.com/itm/350919777680?ssPageName=STRK:MEWNX:IT&\_trksid=p3984.m1497.l2649 and probably paid too much. First I was hating on it. It was totally dead until I found a momentary micro switch inside and pushed it. That brought it to life. It came with no instructions. I filled it with laptop pulls and it seems to work great. I don’t know if it’s the full 2A, but it charges my Galaxy S4 fast and that uses a 2A charger. A 1A charger on the S4 is takes forever to charge it so I’d say 1.5A-2.0A at least. It also charges up ok off a PC USB port or any good MINI USB charger connection. I don’t remember if I used USB 2.0 or 3.0 port. This is just a FYI. I could review it, but I imagine there are better out there. Heck, this same one is probably on other sites for $3.99
- Joe