I set it on low and was going to see how long it was going to last on the tf flame protected 14500. i had it on for maybe a half hour then noticed the light turned off. i was laying in bed so i figured maybe the batt was low. i tried it at work with a alkaline aa with no luck. had it on there for abouit 20 mins no light but the cell was warm. tried another 14500 tf that i know works on xeno e03. still no light. i held it up to my ear and could hear a buzz for a second but still no light when the batt makes contact.
Mine have a buzzing sound in the tail once battery made contact even when the switch is turned off and no light emitted. So wont be testing 14500 battery as it will definitely kill the light.
My light was working ok for the last week onh6 14500s and died again last night so i opened it up today. its got green thread lock compound so it takes a little effort to open.
the little spring is the positive contact and the brass pill was loose. after tightening and putting it back together its working again.