Imalent DX80 Gen2 .. need help to test for faults

Thanks for the help hiKARInoob! Thought I will be left in the dark with this one lol. You lost me on the 4S2P configuration, not sure what that means or how to go about it. I have a DMM but how would I test the max voltage on that battery pack. After the charger says its full, do I just unscrew the battery pack and check voltage that way?

Gearbest has a 7 day DOA period: https://www.gearbest.com/about/warranty-and-return.html#item3

There are eight pieces of 18650 cells inside the battery pack (Samsung 30Q). These are arranged four in series, resulting in 4 x 4.2V = 16.8V. And two of those parallel, so voltage remains 16.8V. This is the maximum (ideal) voltage when fully charged. Minor difference is of course possible.
The centre metal plate of the battery pack is the positive, and the outer metal edge is the negative. So have your DMM set for DC voltage, and put the red probe on the centre positive, and the black probe on the outer metal ring of the battery pack.
After fully charging the DX80, the OLED display should read 16.8V. If you remove the battery pack, you can check whether this value is correct. It’s just a simple test that you can do.

You always come right to the point and detail it out so a noob like me can understand. What can I say except a big thanks, that is all I needed to know to get the job done. Really appreciate the help on this.

I should have read the whole DX80 thread as all the answers were there! Next time I will search and read more before posting. If there is a way to delete this thread, please do mods!

Cheers and don’t worry about this thread. Information is scattered throughout this forum; some people complain about their DX problem on Gearbest’s sales thread only. You’ve probably read this by now, but there is also a structural problem with the XHP70.2 emitters only lightening up partially, like only half of the emitter. It’s a really odd defect.

Cheers, ok I won't overthink it then lol. Yes, I read about the problems. I wonder if it is just a defect from Cree itself? But I don't think I have read anywhere of that problem with other flashlights using the 70.2

Exactly. The interesting thing is that it’s a problem (half lit emitters) only occurring with the DX80. If it were a bad batch of Cree leds, then surely it should have been picked up by led gurus on this forum, as well as reports found of other manufacturers suffering from this bad batch. This is not the case, so I suspect it’s Imalent not doing something right. Probably incorrect reflow procedure (of the leds to the led board).

I would suspect the same. They must be aware of it as it seems to be somewhat common with the DX80. I thought they got a new manufacturer for the updated version but maybe they didn't. Maybe it's as simple as turbo mode creating too much heat and as a result all odd problems start surfacing. I've seen the youtube video where the DX80 in turbo mode sets paper on fire almost instantly.

My take on the entire DX80 thing is that this is very high performance light.
As such, not only are high quality components critical, BUT,
The workmanship during assembly has to be painstakingly and fanatically excellent.
Anything short of that will lead to failures.
Lessor workmanship would get by with low performance lights, but not this one.
I suspect the flaws come from poor assembly practices.

I agree and failure rates have to happen on anything, especially something like this because one way or another humans are involved. I've scanned youtube and the web and still I don't see too many people saying they have problems with the DX80. Curious six more months from now what pops up. I've been lucky so far that none of my flashlights cheap or high end have had any problems yet.

The DX80 i received has the XHP70.2 lets, so far it works great with no issues. Where is the link to the thread where one has shorted?

I couldn’t find it here on BLF (yet), but here’s from TLF (scroll down): Imalent DX80 allgemeine Diskussionen | Taschenlampen Forum

That was a good find on the taschenlampen forum about the short. That is possibly the guy that posted in the banggood forum that I quoted in my first post when I started this thread. I translated a little and here is what he said how it happened.

"The dx80 was not turned on at all. The flashlight was not hot. As it happened, I mechanically locked the light when it was turned on in mid or high mode, then I unscrewed the battery compartment after a second to reset the mode memory, and there was a quick flash and pop then smoke."

Then further down the thread he said he was sorry and that he unscrewed the battery a little "whilst the light was on" so maybe he just did a no no. That is a real long thread and a detailed one and it will take time to read, but from what I read so far, it is suggested never to unscrew the battery pack with the light on and one guy said his shorted but his light was off and in lock mode and he was wondering maybe not to lock it when unscrewing the battery. Lots of really good info there I must say.

Even though i cant read & understand the test parts, the It looked like a trace blew out from the photo, (at 16 volts and high amps a blown trace can arc like a welder and do some damage. Concidering the battery pack is designed for high current & volts to drive that wattage, it can likely blow out a small trace easily if surged when on turbo and unscrew the body to cause a surge.
EDIT: i just looked at my DX80, and the one i have has a different driver cover, ( without those three openings showing the driver back.

DBSAR, google translate does a great job when reading that forum. If you have google chrome, just right click anywhere on the page and choose "translate to english".

For safety, it just make sense that the light is always off when unscrewing the battery pack. Maybe in newer versions, Imalent may take that into consideration and have some type of fail safe protection if unscrewed when the light is on for newbies. If you have a different driver cover, maybe its a newer and better driver too hopefully.

I did use Google translator after to read some of it. :slight_smile: He indicated he did unscrew the body when it was on. A bad idea in any light of that magnitude with high current & voltage. I even avoid that with smaller lights, ( except single cell 1.5 volt twisties i have.

If you have google chrome, you can also right click any page and choose "Translate to English" and will translate the whole page which makes it much easier to read a thread. I fully agree and that is why I started this thread in the first place. Now we know for sure it is a bad idea, especially with the power of the DX80. I've never done it on any of my lithium lights ever.

If i get the time i may do a amp load test (using a shunt-type amp meter with #10 gauge wires) to see how much the DX80 actually pulls from the battery pack on turbo after a full charge.

Different light, voltage and current, but it’s normal routine for something like a Convoy L6. The clicky switch does just that; it cuts off and connects power.
For a light like the DX80 there should simply be a design feature to handle manual cut off. Lot of electrical devices don’t like it when you just unplug the cord, but it is the same thing when you have a power outage. It’s not like your fridge or TV goes poof when the power comes back on. Manufacturers of course are aware of this, hence make sure it’s not a problem.

DBSAR, I'd be interested in those results. It's going to pull a lot of power for sure.