Protected 18650, meaning of "PCB is tripped" ?

[LEDicrous]

@Funtastic

I have the exact same headlamp and it drains the cells below 2v.
… I’ve had many flashlights with no low voltage protection discharge under 2v

2.5v on load should be the absolute minimum but not all batteries, you need to check the datasheet for each model. The reviewer HJK has stated that he no longer runs tests down to 2.5v anymore due to ruining some batteries, he now only tests to 2.8v.

Is there any kind of required standard compliance to prevent such an irresponsible design?!?

@Helios azimuth

Since you are carrying the spare battery, why not carry it in a flashlight with Anduril UI? Then you can check the approximate voltage of the battery you are using by putting it in the flashlight

Or maybe any flashlight that has a LED displaying red when the battery is low could also do the job? I am not sure if my next flashlight would have Anduril UI.

@Funtastic

I just don’t know why someone would risk using those cheap batteries, they are a safety risk, period

Simple by ignorance. I ordered that headlamp on eBay end Jan 2020. At that time, I was vaguely aware that I should use genuine brand name 18650 cells. I just ordered those 2 cheap cells anyway, at least I could use the headlamp right away. In fact, I think most customers, myself included would feel happy as they have no way to know to judge the quality of the products.

Thanks goodness I got educated now thanks to BLF members. And the reason was pretty silly, I was looking for a way to disable the next memory mode in my other eBay flashlight. That was then I discovered a whole world of better designed flashlight and in particular about the Li-ion cells. Here’s another example of benefit I had learnt thanks to the BLFers. I bought some DC-Fix Diffusion Film , just to playaround. I put a diffusion film and an orange filter on a cheap ebay flashlight. And miracle, the ugly beam is transformed into a nice warm light without any hard hotspot.

So now my solution is simple. I’ll give up on those cheap 18650 cells and that F&^%! headlamp. Or maybe keep it around as backup. The winter is over now, the evening walk is not that dark. I have almost a year to order a multimeter, brand name cells & headlights.