Fenix E25 - odd behavior

Hello

i am trying to figure out if the light is defective or not . I just got it today .

i mounted on my moutain bike and went for a ride . Outside temprature 10 Celsuis . Light was ok for 30min then it started shutting off . I switched it off , then on and it could not stay powered on for more than few seconds . Tried again and again , same results

i got home and brought it in with me , in room temprature . Its now working fine .


is it a lemon or not ? thoughts ?

What type of batteries did you use? It could be the batteries not likeing the cold weather. Try using Energizer lithium and see what happens.

panasonic alkaline i used

Alkaline is not good in cold if I recalled correctly. Also, if it's a light you like, don't use alkaline.. It leaks and destroys your light. Try lithium and let us know if the problem still persist.

Also check that the retaining ring holding the tailcap switch is tight if that model has a tailcap switch i cant remember


Sent from a mobile telephone

Sounds like the behaviour of a healthy light with bad batteries.
Alkaline aren't very good at providing the needed current on high when they get colder so it is like they are getting drained.
Then when the light get in to room temperature again they start to work again and have some more juice left.

So for best performance of your light, and to avoid the risk of leaking alkalines, get some LSD NiMh (as eneloop).

Also Energizer lithium AA are good but if you use your light as bike light it will probably get expensive.

You've received some expert advice here. Alkaline batteries are not reliable at (1) temperature extremes, & (2) long storage (they leak). Energizer lithium AA are superior batteries, but as GunnarGG suggested.... expensive!

HotWire said:

You've received some expert advice here. Alkaline batteries are not reliable at (1) temperature extremes, & (2) long storage (they leak). Energizer lithium AA are superior batteries, but as GunnarGG suggested.... expensive!

Click to expand...

gotta get me some AA lithium rechargables then

thanks !!

DimGR said:

gotta get me some AA lithium rechargables then

thanks !!

Click to expand...

No no no.. Either get LSD nimh rechargeable or Lithium battery (throw away). Not rechargeable lithium. Please don't mistake lithium with rechargeable li-ion. 2 lithium AA is okay in your light, but 2 rechargeable li-ion might kill your light.

DimGR said:

gotta get me some AA lithium rechargables then

thanks !!

Click to expand...

Noooo! Just AA primaries (single use)! The lithium rechargables (14500's) are 3.7V which will fry your light!

If you want re-chargeables, go with some Low Self Discharge NiMh cells (1.25V). They won't leak and damage your light like the alkalines might!

Edit: Too slow to hit 'reply'!

DimGR said:

gotta get me some AA lithium rechargables then

thanks !!

Click to expand...

No, no, no!

Lithium or rechargeable.

Energizer Lithium are 1.5 V (or up to 1.8V when new) primaries (non rechargeables).
That's why it gets expensive if you use the light a lot.
But they are very good and work also when it's cold.
if you have a light in your car for emergency use it's a good alternative.

The rechargeable ones are NiMh. They also work good in moderate cold but not as cold as lithium maybe. But a bit below 0 degree C is no problem.
They are also very good at keeping the voltage up during load (as opposed to alkalines)
If you get LSD (Low Self Discharge) they keep the charge well.
Non LSD often have better capacity but will drain just sitting on the shelf for a couple of month and needs to be charged before use.

There are rechargeable lithium-ion batteries in AA size (called 14500) but that is something different.
They have a voltage of 3.7V and will fry your light.

I would go for LSD NiMh like Eneloop or some other similar.
It often says "Ready to use" or something like that on the package.
I have tried GP ReCyco, Duracell and Varta with good experience, and of course Eneloops.


Edit:
I started writing this reply and then been talking in the phone for almost an hour before I posted.
Then I saw you guys already reacted the same way.
Dealgrabber: No, no, no
Gravelmonkey: Noooo!
Me: No, no, no

I think we have seen to many threads about this... :laughing:

dealgrabber2002 said:

What type of batteries did you use? It could be the batteries not likeing the cold weather. Try using Energizer lithium and see what happens.

Click to expand...

I know 10C sounds cold but it really = 50F which is not exactly cold IMO. Certainly should not be cold enough to be effecting any batteries. That said, it sounds like a weak battery issue to me anyway.

It does sound like weak batteries. However Alkalines should still work just fine at 10 Celsius, especially in a warm flashlight, unless they're nearing end of life. When batteries are too weak, they will regain a little voltage if you give them a break, but won't work for long. You'd definitely save a lot of money with some good NiMh rechargeables, though, and get a bit more runtime while helping to save the environment.

im thinking the batteries were running out of juice too.
30 minutes on high mode would do that to alkalines.

dealgrabber2002 said:

No no no.. Either get LSD nimh rechargeable or Lithium battery (throw away). Not rechargeable lithium. Please don't mistake lithium with rechargeable li-ion. 2 lithium AA is okay in your light, but 2 rechargeable li-ion might kill your light.

Click to expand...

I found this very enlightening. My E25 is my EDC, so it goes everywhere including Michigan's chilly winter and spring weather. I'll be investing in some extra LSD nimh rechargeables, since that will save the expense of lithium AAs. I keep an 8 pack of Li AAs in my backpack, since cold does not degrade the charge.

Good thread with many good responses!

Thanks to all for the valuable info!!