Fenix E12 runtime : Is this possible/normal?

db4rings

Newly Enlightened
Joined
Sep 10, 2017
Messages
25
Hello all,

First of all, I have been a long time observer here, and today I signed up and this is my first post.

Anyhow, I have been EDCing a Fenix E12 for over a year now and on Friday I decided to test the maximum runtime on low mode which is at 8 lumens as advertised.

I am shocked to find out that I have been running it continously non stop for 65 hours on Energizer Ultimate Lithium and it shows no sign of dying, dimming, getting hot or anything else.

Fenix states 20 hours on alkalines and 40 hours on rechargables.

I Will re-post the total time once it dies out which shows no signs of :)

I have read that Lithiums will drain slower on low output but isn't this on the extreme? I am really surprised.
 

gurdygurds

Flashlight Enthusiast
Joined
Feb 7, 2014
Messages
1,993
Sweet! E12 is a cool light and a few others have done runtime tests and been impressed with performance, BUT you may be the first to test the runtime on low . Especially with a Lithium. Keep us posted on the grand total. Welcome to the forum. :thumbsup:
Hello all,

First of all, I have been a long time observer here, and today I signed up and this is my first post.

Anyhow, I have been EDCing a Fenix E12 for over a year now and on Friday I decided to test the maximum runtime on low mode which is at 8 lumens as advertised.

I am shocked to find out that I have been running it continously non stop for 65 hours on Energizer Ultimate Lithium and it shows no sign of dying, dimming, getting hot or anything else.

Fenix states 20 hours on alkalines and 40 hours on rechargables.

I Will re-post the total time once it dies out which shows no signs of :)

I have read that Lithiums will drain slower on low output but isn't this on the extreme? I am really surprised.
 

db4rings

Newly Enlightened
Joined
Sep 10, 2017
Messages
25
Sweet! E12 is a cool light and a few others have done runtime tests and been impressed with performance, BUT you may be the first to test the runtime on low . Especially with a Lithium. Keep us posted on the grand total. Welcome to the forum. :thumbsup:


It finally died at 74 hours 12 minutes and 34 seconds.

Thank you and look forward to curing my diesease here lol
 
Last edited:

iamlucky13

Flashlight Enthusiast
Joined
Oct 11, 2016
Messages
1,139
Yes, that is definitely possible. The Energizer ultimate lithiums store more energy than either alkalines or rechargeables, and at low to medium discharge rates, they maintain their voltage better. On the other hand, the ultimate lithium might not do quite as well as a rechargeable on max mode.

Also, output varies between samples, so you might have one that runs a little lower that normal (which I'd in some cases consider a feature for low mode), giving you more runtime.

Thanks for sharing your test!
 

db4rings

Newly Enlightened
Joined
Sep 10, 2017
Messages
25
Yes, that is definitely possible. The Energizer ultimate lithiums store more energy than either alkalines or rechargeables, and at low to medium discharge rates, they maintain their voltage better. On the other hand, the ultimate lithium might not do quite as well as a rechargeable on max mode.

Also, output varies between samples, so you might have one that runs a little lower that normal (which I'd in some cases consider a feature for low mode), giving you more runtime.

Thanks for sharing your test!

I did expet it to be better than both but I am stunned at nearly double the time the rechargeable.

I will give it a try and see on high mode just to see how it does against rechargables.

Also, I was running the Klarus Mi7 and it ran for 76 hours.

YW :)
 

Swedpat

Flashlight Enthusiast
Joined
Jan 5, 2008
Messages
3,448
Location
Boden, Sweden
Hello all,

First of all, I have been a long time observer here, and today I signed up and this is my first post.

Anyhow, I have been EDCing a Fenix E12 for over a year now and on Friday I decided to test the maximum runtime on low mode which is at 8 lumens as advertised.

I am shocked to find out that I have been running it continously non stop for 65 hours on Energizer Ultimate Lithium and it shows no sign of dying, dimming, getting hot or anything else.

Fenix states 20 hours on alkalines and 40 hours on rechargables.

I Will re-post the total time once it dies out which shows no signs of :)

I have read that Lithiums will drain slower on low output but isn't this on the extreme? I am really surprised.

Interesting. I have seen some other example of odd claimed specification by Fenix. Often alkalines are better at low brightness levels than NiMh cells. And rechargeable cells better at high brightness levels.
 
Last edited:

dhvl1357

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Joined
May 20, 2016
Messages
7
I'm not surprised because Fenix have always had amazing efficiency drivers. For eg., the E01 puts out 8-12 lumens for 20+ hours so 3x that for AA sounds about right.
 
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