18650 Battery Question

My WF-139 charger arrived today along with a gift, two Ultrafire 2400mah TR 18650 batteries(link is exactly what i received) non protected. I'm a noob ,so I'm not sure of the quality of these particular cells. I tried to search for reviews but unsuccessful. Can the battery experts chime in , much appreciated.

1st cell measured at 3.74v

2nd cell measured at 3.63v

Does anyone recommend i use these cells? I know most XXXfire cells have a bad reputation. I'm afraid of destroying my flashlight, fingers flying off or worse burning down my home.

I have one of theses cells. The are ok for a Q5, R2, R5 LED but not for a XM-L.

Which flashlight do you use?

I will be using in a SF L2 with a XPG-R5, is it safe for a P7 drop in?

Alright that gives me reassurance , thanks Be-Seen Triker!

This is my first wf-139, I just tried charging the ultrafire cells, I noticed the light indicator lights while charging are blinking (red light) Ive read elsewhere this is normal. Is this true?

Yes. It stops every second or so to measure voltage and this makes the red light blink.

Thanks Don

With a Solarforce L2 there is no problem to use the cheap batteries. If the flashlight losses brightness measure the battery. The voltage should not be under 3Volt.

OK. Thank you Buwuve

I havent seen any negatives about the blue 2400's but.... If you can do a discharge test I would recommend doing one. In my experience with the xxx-Fire brands is anything in the 1400mah and under range is recycled.

If your running a multi cell flashlight then I personally would not use any Chinese brand battery. Stick with LG, Sony,Samsung ect

Can you put a link (SOP) on how to perform a self discharge test?

I'm curious what the difference would be using cheap batteries in a Solarforce L2 compared to any other host? Cheap batteries are cheap batteries, who cares what they are in, since the host is just a case and a switch?

don't get me wrong, I've used a lot of cheap batteries with no issues, I just wondered what the L2 had to do with the price of tea in China.

I believe Buweve meant to say , it would be fine to use the non-protected batteries in a SF L2 host with either a XPG-R5 or P7 drop in and not a XML drop in.

Why not a XML?

i think it should be fine and no need to worry about ruining your cells.

HaHa...Thanks

As far as chinese cells go, the Trustfire Flames are great cells in all sizes. One of the few quality chinese cells. Every pair I've bpought are perfectly matched and consistent in voltage and output.

As for L2 lights, the solarforce have nice drivers in them that will turn off the juice when the batteries get below 3.0V so it's actually safe to use unprotected batteries in them since the light itself has a protection circuit built in. Just dont use unprotected cels in a direct drive light or in pairs and you should be fine.

Thanks for the info JM !!

Actually it's more like they have buck drivers that just stop working at low voltage whereas most of the really cheap dropin's (esp multimode) are DD. DD is actually not that bad for xr-e's. They give you a bit of light that drops substantially when the cell is running dry.

In my post I mean the combination of gen1.3 (SF L2 and R5 Drop-In) - sorry for my unclear post.

For full brightness of a XM-L you need about 3A. Sometimes cheap batteries do not offer 3A. Another point is the missing protection of the battery. If the batteries support 3A and the Ultrafire XM-L drop-in do not turn off by low voltage, you can damage your battery.