Have any of you experienced an acrid burning smell in the tubes of your lights after using them? I have seen this in two different lights with different manufacturers and different batteries. Both times the smell occurred even after using the light briefly. The batteries were barely even warm when pulled, no visible leaking or anything obvious Like that. Like less than a minute of use. The smell is pretty strong like a burning solvent. Kind of like WD40. Thoughts?
Some kind of lubricant that’s gotten on the tailcap spring heating up?
Since it’s done this in two different lights, I don’t think it’s a battery issue or a leaking capacitor in the driver.
Yes I have noticed this, after use in a few cheap zoomies but also when new so before using it.
All with very cheap lights though.
Are the watches defective in any way? [EDIT: LOL I mean flashlights!… I was surfing my fave watch forum while also on BLF). Might keep on the look out for an over-current situation with the -B or +B springs.
My sanyo’s 14500 have a weird smell to them, specially in the Mi7 less so in my moonlake but still noticeable. But I wouldn’t call it a burned smell but rather somekind of chemical smell. Don’t really know if it comes from the lights or the batteries. Never smelled the battery tube before running the lights. Lot of things from China have a weird chemical smell to them though. They might be exporting cancer for all I know 
Is it possible the battery are venting and if the flashlight are air tight the smell is staying within the tube?
Yeah I’m thinking that it is some kind of bad lubricant smell maybe? Like a weird machining/factory smell. It’s sort of reminiscent of a burning electronics smell and seems(?) to get stronger with use. Also a little reminiscent of liquid Triflow or WD40. It’s hard to exactly describe how it smells. I have noticed a similar smell on one of my really cheap zoomies (I think in that case the smell was there before use too). Honestly, I’m not sure if the smell was there before use because I’m not in the habit or smelling battery tubes before using a light. But I definitely noticed it after use. Unfortunately I’ve noticed this on a couple not-cheap lights.
Possible venting was also my most immediate concern but the battery was not even warm and I didn’t notice anything else strange.
Smell is also there even if I leave the light outside (and open) for 10+ minutes.
I haven’t noticed it with my flashlights. I’ll keep an eye on it and let you know if it happens here.
Ha the first time I smelled it I ran outside because it smelled how I expect venting cells to smell
Could it be remains of flux that you smell? If you can unscrew the battery tube from the head does the tube or head smell stronger?