Ultrafire 18650 Protected Feedback

[TheWalkman]

Anyone have any experience/ feedback regarding Ultrafire 2400mAh 3.7V Protected 18650 cells?

 

[matrixshaman]

I think that's the one I got from DX - like $6.02 - it's protected and it's working great so far - haven't run it too much yet - still on the first charge and plenty strong. I checked the voltage after using it a couple minutes in a very high draw LED light (I think mine was pulling 1400ma) and it was still over 4.0 volts.

 

[mudman cj]

I think they are fine for LED lights, but I would like to caution against using them in multi-cell applications. I tried two of them in a Mag 2C to run a 6 cell bulb, and right away I ran into problems. The electrodes do not protrude past the plastic wrapper on either end, so magnets or foil balls or some other means must be used just to make contact. This caused me to run out of room fast since I already had the tail cap spring out just to get 18650s in their in the first place. I tightened the tailcap too much trying to make contact between the body and the tailcap and dented one of the battery vent caps on the solder bump I added to the positive contact of the flashlight (again, to make contact past the wrapper). That was the end of that battery. It quickly dropped to 0 V.