Led Lenser X21 users, how hot does yours get??

I have had my led lenser for a little bit over a week now, love it, cant put it down when it gets dark.

Just one question the head of my one get very hot within 5 mins or so? is it normal for all the lumens it putting it out or is it because i use rechageable GP D 1.2 Volt nimh 9000 mah batteries?

all info much appreciatted.:candle:

First... In any LED flashlight, it is quite necessary, and a good thing for the body to heat up quickly. This means that the heat that the LED produces is being moved away quickly, from the LED, and prolonging the life of the LED.

Second. LED Lenser/Coast lights are not meant to use Ni-MH/Ni-Cd/Li, Li-ion batteries for one reason. they are direct drive, with current to the LED (s) being only limited by a resistor.
They are meant to use alkaline only, as the internal resistance of that chemistry allows the current to the LED to drop as voltage drops (under any load over a 1-2 100 milliamps), thereby reducing current to the LED, and hopefully prolonging the life of the LED (s). This is necessary because most (if not all) Coast/LEDLenser lights are direct driven.

Thanks for the info!! will take the rechargeable out!:candle:
I saw Energizer D Alkaline battery at the shop near me, but they only 1.2 Volts is that alright?

the specs are

Type: Alkaline
Product Line:MAX Alkaline
Size- D
Capacity:2500 mAh
Output Voltage:1.2 V

why i ask the Alkaline batteries given with the torch are 1.5 Volts

is important to only use Alkaline batteries 1.5 Volts???

Umm.... something doesn't sound right there. As far as I know, alkalines and carbon zinc battery chemistries give you 1.5 volts. NiCD and NiMH rechargeables give you 1.2 volts. :thinking:

Edit: yep, something is up. Here is the Energizer MAX Alkaline web page for South Africa. 1.5 volts for D (click on the picture of the package and it will pop up the specs on the right):

http://www.energizer.co.za/products...tegoryID=0412270d-817c-427e-bdc3-a5d4dff23a15

Space-time... Did you read my post at all? I clearly state the reasons why alkaline is necessary.

Yes, Alkalines are 1.5v nominally. Under any load over a few hundred milliamps, the internal resistance of the battery chemistry causes voltage to drop to closer to 1-1.2v. The drop in voltage is also accompanied by a drop in current, thus preventing the light from ruining it's LED's, due to the nature of the "regulation" and inadequate heatsinking.

Ni-MH batteries have much lower resistance, meaning that while they are "only" 1.2v nominally, and can maintain that voltage under extremely high current drains. The small drop in voltage from 1.4-1.5v off the charger is not accompanied by a substantial drop in current output, therefore, running Ni-NH batteries in this light during extended runtimes could damage the LED's, from a combination of too high voltage, and sustained amounts of current, coupled with the inadequate heat-sinking.

John_Galt said:

running Ni-NH batteries in this light during extended runtimes could damage the LED's, from a combination of too high voltage, and sustained amounts of current, coupled with the inadequate heat-sinking.

Click to expand...

The very reason I didn't get an X-21. I'm not forking out $20 a month for alks.

Even with Eneloop AAs, the 7 LEDs draw 7 Amps

Your GPs might fry the light if you aren't careful. Maybe they are not that much of a danger for the XR-Es if you let them rest after charging.

Just wanted to warn you.

thanks for the info gents!! not using nimh on the X21 anymore, only on my tk40

Well, I don't know how exactly the X21 behaves...but I mean, if it draws 7A already with Eneloops...^^

Maybe you could measure the draw with the Ds...might be interesting. The LEDs can bear more than 1Amp, but only for limited (short) time. With good cooling. Just make sure you don't leave it on too long then, or, as you know, it will overheat quickly.