My acebeam t27 uses USB c charging and it has been totally flawless. So does my Acebeam headlight, so does my Fenix headlight. All of these also work as powerbanks. I have had them longer and use them more with no problems.
Granted I don’t think any of them charge at the voltage sofirn did.
This actually made me think about another question. I was disappointed that none of Ace beams multi-cell lights had onboard charging, but now I’m beginning to think that they must do that for a reason. Most of their individual cell lights do have on-board charging. obviously charging each cell individually is better rather than charging multiple cells in a series. Do you guys think it’s a better design to just avoid onboard charging entirely when we are dealing with multiple cells?
Well i havent heard of this issue on the single cell sofirn sc31 which has been out a year now (have given away 2) or sc31b (given away another 2)
I suspect single bat lights are much simpler (no screws) and most of em use micro usb with lower voltages
If i want a reliable light as possible, it wouldnt have usb charging, of course it would have simple modes, not be pushing the output too hard and a timed (not temp) stepdown
But we dont want simple lights we want fancy ones with usb charging, lotta flashy functions, customizable UIs and blinding outputs
You will find that many folks here having less than reliable lights is no big deal, never mind warranty
I’m only halfway through this thread but this is what I was going to suggest. Too many cheap chargers just “assume” this or that and can potentially fry something that’s not meant to take high voltages.
Eg, old usb used to be limited to 500mA unless negotiated higher, but I got at least one combo of tablet and cheap “lipstick” powerbank that pushes enough current to get both (micro) connectors quite hot, and the powerbank/cell gets quite warm. Great for a quick boost but hardly healthy for either device. And that’s a 2-wire charge-only cable, no data connections, so no negotiation is even possible.
A better design? Not really. More complex, absolutely. There are plenty of devices that can charge multiple cells. Take power tools for example. It wouldn’t make sense to charge each cell individually. But then balancing comes into play.
For this light, though, the cells are in parallel so its essentially just charging a single cell. Not really any different than an individual cell light having a charging circuit…
The smell of burnt chip is really awful and very “sticky”.
A chip on a previous laptop’s motherboard got fried caused by a short (don’t ask…) and let out the “magic smoke”. I just got one or two whiffs but it stuck in my nostrils. Just thinking of the smell makes me feel sick.
Even after 1-2 years, the smell is still there near the disintegrated chip. I avoid sniffing or touching near it. Incredibly nasty.
I’m not familiar with the technicalities of it, but I know that a charger measures certain parameters to determine when a cell is done charging. If it’s charging three different cells in parallel then it can’t really do this effectively. It has to treat all of them the same even though there are manufacturing variances that may make it so that not all of them are exactly the same. I’m sure this is particularly true when you are dealing with low quality Chinese cells like these. I would venture to Guess that even if you had three brand-new high-quality cells in a charger the charges each cell individually they are never going to finish at exactly the same moment. Am I looking at this incorrectly, or discharging cells in a series like this always guarantee that they won’t be charged quite right? Not that this is really directly related to the problem I had here. The problem I had here I think is pretty clearly low quality manufacturing coupled with probably insufficient R&D and understanding of higher voltage charging
Well that’s depressing. So this probably won’t go away? I wonder what it’s off-gassing exactly. I don’t think anyone really knows what it is or what effect it could have on health.
It’s created by the burning of the materials in the chip. What materials those are exactly could be determined by looking up the chip on Mouser.com or the like. I don’t think it would help your situation though. Mostly everything just needs a good wash. Including your walls and floor apparently.
I think you’re right that charging with individual battery bays like in an external charger is safer than charging multiple cells simultaneously in parallel inside a flashlight.
That said, the photos OP posted appear to show undamaged batteries that did not vent. The problem appears to be something blew inside the driver, but fortunately the batteries were unaffected.
The cause is unknown. It is mostly likely poor quality control or a defective component on Sofirn’s part. But it could be a defective USB-C charging cable supplying too much current and blowing something on the board.
I’ve read able people having their laptops and cell phones destroyed when they tried using cheap generic USB-C cables that were miswired. I’m curious to know if if OP was using such a cable, if the cable was new, or if it was the original Sofirn cable that came with the light.
Look at the third listing image. Both the NarsilM and Anduril versions show 5V2A charging but the S version shows 5V2A,9V2A,12V2A so apparently the charging circuit was changed for the S version.
Okay I looked up the cable. It’s an anker cable which is very well reviewed on Amazon. It’s a cable I have owned for 2 years and the cable still works just fine. It has charged multiple cell phones and three other flashlights several times with no problem. It even charged this light five times and the bfl version even more times than that. I really don’t think it’s the cable.
The cells are in parallel, not series. But even when charging cells in parallel, it is important to use similar cells. Because, like you said, the charger sees the cells as a group. However, from what I’ve read, the Sofirn cells have historically been pretty decent cells, not low quality.
I’m glad you posted this, though, because I actually just ordered a SP36S last week. I’ll do some poking and prodding with the DMM with some of my USB-C cords and power supplies when it shows up.
It’s really not that surprising. 12v 2amp is 24 watt. Heck, most household light bulbs are only 6 watt these days. That’s plenty of power to fail spectacularly.
You’re not working around the stuff 8 hours a day. You were exposed for what… a minute? You’ll live. Nasty crap smells bad, and while it’s not good for you, everything is about dose. A small amount won’t hurt you. If you got a blast of a lithium-ion fire, that would be worse, but your batteries were fine.
The smell will clear in a few days. If you stick your nose up to the area, you’ll probably smell it for months or years. Some of that is real, some of it is just your imagination exaggerating things. Just keep your nose out of it, and you’ll probably never notice it.
Send the light back to Amazon and get a refund. Sure, it would be cool to tell Sofirn about it, but 99% chance is they won’t do anything about it other than replace your light.
Bottom line is that any high-power electronics can fail in bad ways.
Actually, it’s really not that important. Terminal voltage will be exactly the same across all cells. Higher capacity cells with higher internal resistance will self-limit as that resistance acts as a ballast. It’s like having 3 water-tanks — 1pt, 1qt, 1gal — with hoses joining all them at the bottom. They’ll all fill at their own rate, and the level in each tank will be exactly the same.
The reverse happens when discharging. Voltage will sag in lower-drain cells so they won’t discharge as fast as higher-drain cells.
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That said, and to keep from having to write a separate reply, most charging circuits pretty much use the same chipset, so there’s no real “better” or “worse” design. Same with usb chipsets (eg, voltage negotiation for usb-c).
Hell, whether it’s wifi, bluetooth, whatever, there are typically just a few chipsets to pick from. Almost no one rolls his own, as it’d just be reinventing the wheel.
I agree. It doesn’t sound like it’s the cable. If it was, you’d know the first time you tried to use it.
Definitely sounds like a defective light. Something went kablooie on the driver. Your options:
Return the light to Amazon for refund.
Contact Sofirn to let them know about the problem and to ask for repair or replacement. This might also enable Sofirn to figure out exactly what happened so they can fix it and others don’t experience the same thing.
You could ask Sofirn for damages. I doubt they’d pay anything for just having a headache without any further medical diagnosis. But if you spend thousands of dollars on a cleaning service, you could potentially ask for reimbursement.
If Sofirn fails to pay for damages you could try suing them. This might not be worth it if their office is not located near you. Trying to sue in another country could be a pain. Probably not worth the effort for minor damages such as caused by this. Before any litigation, it is a good idea to contact Sofirn to see how willing they are to work with you and make you whole.
You could try sending the light to someone on this forum for dissection and analysis. I’d recommend securing a replacement or refund before doing that though.
