Which battery have you used? Have you tried a eneloop?
14500 make a huge differents in brightness, with a AA it is to dim for me too.
But with a lion you will have the hassle with thickness…
I have the T10, which is the previous model. A 14500 works in it but only works for moonlight and high—it flickers on medium. But it won’t fry anything. I’m usually pretty daring about trying an li-ion in all my lights … in the name of science of course 
Hi,
I tested with a lightly used alkaline (I think 75-80% capacity left).
Insert a new alkaline, and it is much brighter than before. I could believe it was 169 lms by now. Just almost as bright as my 200 lms Ultrafire….good impression.
But after 15 min, my good impression gone. I started to detect the brightness dropped quite a bit.
My perceived brightness with Sanyo alkaline (high):
0-15 min - 160 lms
15 min - 120-130 lms
20 min - 100 lms
30 min - 60 - 80 lms
40 min - 30 lms
45 min - 10 lms
50 min - 5 lms
55 min ——-> dead, but reinserted battery, the led lighted back up brighter like 10 lms, but fastly decreasing to 3-5 lms.
60 min - 135 min - 1-3 lms seemingly stable for long time but became dimmer in the last 10 min & died, but got resurrected by itself after 1 min, very dimmed like 1 lumens
135 - 150 min —> very dimmed like 1-2 lms (brighter than firefly)……I stopped the test though.
Does this flashlight have regulation with alkaline ???
Perceived brightness with Sony 2100 mah NIMH :
0-40 min - seemingly more stable in brightness. If any drop, I couldn’t see it clearly.
41 - 50 min - a little drop in brightness, not sure how much.
50 - 55 min - decreased brightness, maybe 80-100 lms. I didn’t realize when it began.
65 min - like 20 lumens
———-> dead, but reinserted the battery, the led lit up again like 10 lms
70 min - like 10 lumens
75 min - like 1-3 lumens
80 min - less than firefly
83 min - dead
At least I can see some regulation with NIMH battery, but not with alkaline.
I also wonder why the light was dead when voltage is low, but reinserted the battery did the trick to make it work again for quite some time.
Well at least the performance is not as bad as I thought with Nimh battery. Not happy, but not disappointed either when I paired with Nimh.
Actually after this experience, I became more appreciative to my old Ultrafire mini torch (which I thought cheapy product , so I treat it with no respect at all) :bigsmile:
With 16337 650 mah, I don’t see any drop in brightness for 30 min, until suddenly it dropped to 10-20 lms flashlight for the next 3 min before it dies.
With CR123a 1400 mah, the brightness is constant for 65 min, then again dropped to 10-20 lms for the last 5 min……dead.
I think I owe an apology to my Ultrafire for being so rough & insulting all this time. 0:)
You could try Energizer ultimate lithium or the Nice lithium batteries from FastTech, they are a improvement over alkalines and NiMH but they are expensive if you use them often.
I have a Thrunite T10; I run Eneloops in it, and I absolutely Love it; it’s small enough to use on a keyring, but on high it’s plenty bright, and on the 9-lumen mode(which is Plenty bright in actual Darkness) the runtime is fantastic. Twisty action is as Smooth as Butter. Also, I got it for less than $20 on Amazon. Highly Recommend.
Has anyone baked this flashlight yet?