Fenix LD25 Problem Help!

I have had my fenix ld25 for quite a while now and always refrain from using it for one reason. after about 15 mins of constant on it starts to get lower and lower until it turns off completely and will not go back on until it is completely cool which takes a long time! this has failed me many a time, most notably when it was pouring with rain in the pitch dark and i was setting up a tent! Oh God! is this overheating normal? I do use alkalies that come in a large pack, would buying rechargeable lithiums work?
Thanks! Harry

Try NiMH rechargeables, e.g., Eneloop. You could use lithium primaries, e.g., Energizer L91, but that gets expensive in the long run.

Owner's manual says "Avoid the use of 14500 Li-ion battery, or damage will be caused to the light circuit."

+1 on the previous post; Definitely sounds like a battery issue. I doubt the light goes off due to overheat, it sounds more like the light comes back on after a while because the battery charge goes up after a long rest.

Get some at least half-decent NiMh if you don't want to shell out for eneloops (any store has Rayovac Platinums or Duracell pre-charged batteries). Fenix flashlights are desinged to use NiMh. The can use alkalines, but that's considered like an emergency situation since alkies don't have as much power output as NiMh, and you shouldn't run turbo in that type of situation.

Thanks a lot for the help, i will get some NiMh rechargeables on ebay and see how it does!

Imedion 2400 mAh rechargeables are readily available on eBay and are, IMHO, good value if shipping to your location is reasonable.