The main problem with lithium ion battery fires is that the reaction is self-oxidizing, so you can't put it out by just smothering it. You actually need to cool them down enough so that they don't re-ignite. Plus, once they're damaged, even if you do cool them down enough they're much more likely to short and re-ignite themselves again anyway.
Consider the "fire triangle" - fire needs three things: fuel, oxygen, and heat. With, for example, gasoline fires you can take away either oxygen OR heat to extinguish them, but with lithium-ion battery fires you have to take away the heat to extinguish them.
idk why, but I dug around YouTube for an hour or so to try and find that alarm for you. I stumbled across one that's so close to your description, though it's from a BlackBerry, not a Samsung:
https://youtu.be/bOBaJHw36Dc
Is this the one?