Some start-up questions

[Centrenet]

Hi guys, how are you?

Since I am new to the flashlight industry I do have a few questions. I have already searched this entire CPF forum but I couldn't find any satisfying answers. So If you guys please want to help me, that would be highly appreciated!

What are your thoughts about the WF-139 charger? I own one, including 18650 protected Ultrafire 2400 (grey ones) batteries. The charging process works flawless, as I measure 4.2 volts when the led indicator turns green. This is a dual charger right? Is this a reliable charger and can it be used for allround consumer use? I know Li-Ion batteries need to be looked after, but I know there are consumers (ordinary users) who are not aware of the dangers with Li-Ion.

My last question is about multicell lights. I own a T40CS from Sunwayman and uses 2x 18650 batteries. Are the Ultrafires safe to use in this light? I have read that the cells have to be balanced in order to work properly. I have also read that the WF-139 charger charge the cells independantly so they each cell is properly charged.

What are your thoughts?

ps: sorry if this question is asked before.....

 

[moderator007]

I have the WF-139. Its 2 years old and works flawlessly. Out of all the cheap chargers I have had or have this one will charge to 4.2v everytime. I have heard of them catching fire. But this could have been from abuse or bad battery. I have sold several along with custom maglites. None have returned or gave problems. There are better chargers but this one works like a charm. And yes it does independantly charge each cell. They can even be different size cells.


When running two li-ions in series always check the voltage before installing them. To make sure they are reading close to the same resting voltage. It is also wise to have a closely matched pair. So when there new you can mark them as a pair. That way they should age and take the same using characteristics as a pair. Never use two batteries that are way off in voltage. Charge them up so they are a close match first.

 

[yifu]

I have a Trustfire TR01 which i believe is a rebranded W139 and it works great, terminates exactly at 4,2v and has a crude form of CC/CV implementation. It doesnt deliver 500ma as stated, however.