My flashlight got a 'little' too hot

lucky you caught it.
thermal runaway of li ion is not pretty.
pissed off batteries plus tightly closed aluminum tube = pipe bomb!
bad design if its driver allowed this.
hey lets just dd 18 xhp-70 in this to one up the other guys.
who cares if a few explode.

Mine got really hot but it was after continuous use for some time and then the activation on the 60.000 and 100.000lumens.
Then a “HOT” signal appeared in the OLED screen, the fans were already working and the light eventually shut off (I guess, i can’t remember if it was me that clicked or if it shut off, but I’d bet on the second one).

But yes, it turned really HOT! I wouldn’t expect it to behave differently (on these levels).
On 10.000 lumens, it is weird and not good :zipper_mouth_face:

Wow, good thing you caught this before the batteries reached critical. I wonder how many hours were burned off the LED at this point!

The fans turn on with the higher modes, but not the 10,000 lumen setting.

The runtimes for the other high/turbo modes are less than 1 hour each.

Well that’s a pretty stupid design if the light can reach dangerous temperatures on the levels without fan activation! :person_facepalming:

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Wow, if any flashlight needed a thermal stepdown, looks like the Imalent MS18 does.

the leds may be damaged also

Possibly.

But on the other hand, LEDs are designed to accept heat during operation and reflows. They’re pretty tough. And the operating life of an LED tends to be orders of magnitude larger than the rest of the flashlight anyways. If an LED loses half its operating life from misuse it will still likely last much longer than the rest of the light.

My biggest concern would be the batteries blowing up. And if that didn’t happen, overheating might cause the rubber switch boot to melt, or the solder on the driver and/or star to melt.

The electronics like inductors, FETs, caps, resistors, .etc and leds would survive that, but the solder joints wouldn’t if using sn/pb solder for reflow…wires coming loose can cause shorts and that’s what kills things. Shame on imalent for omitting a continuous cooling loop for turbo on that near $700 light capable of hundreds of watts of output.

This.

And it should have had a temp sensor that automatically turns on the fan and/or reduces output when the light gets too hot no matter what brightness setting the operator is using.

Before seeing this post, that’s how I assumed an MS18 would work. Guess not…

Does seem a bit strange that a $700 light lacks a core safety feature that has been standard on $50 light for several years now.

… at least I assume this is the case based on the original poast. I don’t actually own an MS18 myself.

ChibiM, can you please tell:

- how long did you let the flashlight ON in the 10.000 lumens level?

- did this issue happenned after using the light the higher levels (22/30/60 or 100.000lumens) [meaning ,with accumulated heat]?

  • or was it from “Off” [meaning, with the flashlight “cold”]?

I am checking how mine behaves from “off”/cold (setting it on the 10.000lumens and letting it be there for a period of time), with the batteries around 13.5V (and decreasing from there), meaning , they are not full!

After 15 minutes on 10.000Lumens, the head temperature is ~41ºC (near the bezel), he tube is not warm (~32.7ºC near the switch, ~30ºC on the tube).
The fan did not activate.

It’s kind of like complaining to Ferrari that you were driving 200mph and you had a tire blow out. I think its part of the adventure. To play, you have to pay.

This is totally different, this very expensive flashlight is lacking a basic safety feature that could potentially lead to serious injury of the user - this is entirely preventable. This is more akin to your Ferrari being equipped with an automatic transmission and simply not shifting into a higher gear or something simple and dumb like that - it just shouldn’t happen at all.

Granted, perhaps this is not normal and is a malfunction, but is still an issue that should not be present

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The first thing they’ll say is — You’re suppose to hold a flashlight not Tail stand it on 10000 lumen mode —- I’ve played around with small lights like a S2+ with a fet /triple — tail standing at over 5 amps will produce some serious heat —- but will this kind of power there should be some kind of timer / thermal step down

If you watch YouTube videos of this light in action on turbo or any higher modes, the fan kicks on automatically when it hits a certain temp. The fan itself is entirely inadequate for dissipating 400 ish watts, so it’s mainly there to keep things from self destructing. There’s a malfunction in this MS18 perhaps, and yes, it could be bad.

its just too much lumens in a light to be any practical, whats the point light gets so hot it turns into a bomb ?

No, timer is a poor solution. If it was a $10 light I wouldn’t complain about timer…if it was a $20 light I would have mixed feelings. But it’s a $700 light. There shall be thermal control.

As said before, it’s been a standard in $50 lights for years. Actually in BLF lights for $30 as well.
There is no excuse to shipping such undeveloped UI in expensive light.

But it’s Imalent. Powerful but badly developed lights for a high price.

Sometimes we disable temp protection on purpose because when it’s on the flashlight doesn’t even reach 45°C but the immalent takes it to another whole new level :smiley: