Ultrafire Wf-139 gave out today. Glad it went quietly.


Flashlight Enthusiast
Jun 19, 2008
I never thought I would be posting anything in this part of the forum (guess no one ever plans on it) because I am very cautious when it comes to li-ion charging.

However today while I was working on a flashlight project in my room (too cold in the shop) I figured it would be a good time to put a couple of cells on to charge. I plugged in the charger and placed 2 Ultrafire protected 18650s into the bays. I will be completely honest and say that I know for certain that one of the cells has a bad spot in the shrink near the center of the cell, but I have always been aware of this so I am careful to place that spot UP.

There has been NO modification to this charger since I purchased it, and nothing out of the ordinary has ever happened to it, ie been dropped or been left where moisture could get to it.

When I placed the cells into the charger every thing went just as it always does and the green lights turned to red to indicate charging. After a while I went into the kitchen and had something to eat, and when I came back I noticed that there were NO LIGHTS on at all on the charger:eek:. I quickly unplugged it and removed the cells from the charger. When I picked it up and felt the bottom it was very hot and I could smell a slight bit of a melted plastic smell. Nothing serious happened like smoke fire fumes, and the cells were fine, a little warm but not hot at all.

The main reason I decided to post this is for it to be a constant reminder that there is always a chance however remote, that this could happen to even the most careful of us. I am human like the rest of you and it is not out of the realm of possibility that I did do something wrong, but every thing appeared to be in perfect order, cells were in the right direction etc, as far as I could tell. I think in this case that equipment failure was the cause.

This is a perfect example why I make it a point never to leave these type of batteries charging when I am gone, or asleep. I am also grateful to the Lord Jesus for protecting me, and my house when things happen that are beyond my control.

Have fun, and be safe everyone.