After checking the battery on the tester I put it back in and set it bezel down on a table. In just a minute or two it got crazy hot.
Just guessing:
Sounds like the Tester might have damaged the battery.. Maybe you used the Lithium Primary test, instead of the Lithium Ion test.. not sure.. but I would not use that Tester again... Suggest you use the built in battery check, and read the manual
https://toykeeper.net/torches/fsm/anduril2/anduril-manual.txt
Glad you did not suffer any injury..
> I haven't accessed the advanced UI in order to unlock turbo either.
that does not guarantee that the light could not get turned on at a high enough level to get hot.. Some Anduril lights ship with the Simple mode Ceiling set to Turbo.. (I dont have an emissar, so cant check the output to predict how your light is setup)
does not sound like the light was On anyway.. very scary report.. and still a mystery what went wrong..
===
new info:
maybe the problem Was Actually caused by inserting the battery backwards..
here is a report of just that same situation..
"reversed battery, leads to very Hot light
reversed 18650 in d4v2, cell still works...
I left it in there for ~10 minutes before noticing, the flashlight was super hot (had to use a towel to open it and get the battery out)."
apparently I was mistaken to think the light has reverse polarity protection, so, maybe the issue had nothing to do with your battery tester
glad the light is working normally now, with a different battery.. my guess is your overheated battery might still be good.. if youre feeling lucky, put it back in the light and do the 3 click from off for battery voltage check..
If the voltage is above 2.5V, your battery is probably fine and I will go with the assumption that it got hot because you put it in backwards..
just my opinions, not an expert, though I may sound like one on the Internet.. LOL