Acebeam Three Blinks of Death

I’ve run into something with a couple Acebeam flashlights now, and I’m looking for feedback. Apparently, turbo mode on an Acebeam flashlight depletes the battery much more quickly than I expected. Since Acebeam’s branded 21700 batteries don’t fit into any of my chargers, it has been difficult to confirm this, but I just checked with a Samsung 40T that caused the three blinks of death, and when I checked, it was at ~3.5 volts. I am currently testing to see whether parasitic drain is a contributing factor, though. For the times it happened, I was sure the flashlights had more charge than that, so it’s a little alarming.

The issue is this: I have sometimes picked up an Acebeam flashlight after not using it for a few days, put it in turbo mode, and found that instead of just staying on constantly or ramping down to high, it will blink three times, stay on, blink three times, and keep repeating this annoying cycle. There’s nothing in the included instructions about this, but from my research, I understand that the three blinks means the battery is too low to run the flashlight on turbo anymore, but it’s such an annoying “feature” that I feel like I must be doing something wrong. The flashlight would ramp down the brightness on its own when run at a higher voltage. If I unscrew the battery cap and screw it back in, I can seemingly run it on turbo again for quite a while without the blinks. Why does it blink like this? Does anyone have any information about what’s going on? I’ve noticed it so far on an H30, L30 II and EC50 III.

It might be that the springs have too much resistance when compressed less by the unprotected cells. A spring bypass with desoldering braid may help. Sometimes you don’t even need to solder to the spring - just make a loop by soldering the braid to itself.

Just to clarify, I’m currently using Samsung 40T’s to confirm if parasitic drain is an issue, but I experienced the issue previously with Acebeam’s extra-long 21700 factory spec batteries that are too long to even fit in my chargers. If spring compression is a factor, I don’t think those would be affected.

I didn’t realize it was happening with the Acebeam batteries. That does sound less like spring resistance. If it was just a single light, I’d lean toward it being defective.