Anyone tried the new Wuben C3 flashlight yet?
Just got hold of the Wuben C3 and tried some test.
I monitored the Wuben C3 charging the included Wuben protected 2600mAh 18650 battery. (connected a USB meter to check the USB charge current) -- at around 0.40A charge current (USB side), the indicator on the Wuben C3 will switch from 'red' to 'green', when I removed the battery and checked its voltage, it was around 4.13v with my DMM.
I reinserted the battery and continued charging it with the Wuben C3 just to check what happens. The USB charge current will continue to drop until around 0.15A (USB current) and then cuts off charging (USB meter drops to 0.01A), When I removed the protected Wuben 18650 and tested its voltage, I was surprised it charged to 4.31v ! (I immediately discharged the battery since this is over-voltage).
But I wanted to investigate further.. Knowing that this Wuben C3 overcharges, I tested another "used" unprotected 18650 battery (I know it's going to be overcharged, so I didn't use a new battery but a bit older one, that's still working good). Monitored the charge current (USB Meter side). Charge current didn't stop at just 0.15A but it continues to drop, I think it took about another 1+ hour, the charge current already dropped to around 0.07A, but apparently is still charging. Now this is gettting more suspicious, when I removed the battery, this unprotected 18650 battery already tested at 4.57v (!) with my DMM.
(I hope this old battery didn't get damaged too much, as I discharged the battery to below 4.20v immediately afterwards).
Now getting back to the Wuben included battery -- it would appear that if the C3 flashlight would have kept on charging the Wuben protected 18650 battery, were it not for the protection circuit that cut off the charge current. (to test this theory, I inserted the 4.30v Wuben 18650 to my MC3000 charger, and tried to charge it further (I set to LiIon4.35v so it can charge to 4.35v), and what happens is that the MC3000 will disconnect the charging when it reaches around 4.31-4.32v, which appears to indicate the protection circuit cuts off the charging when voltage goes higher than around 4.31v.
Now, if it had been an unprotected 18650, then the Wuben C3 would probably charge higher voltage (like the 4.57v, which I unplugged the flashlight from the USB power).
It's NOT SAFE to charge with the built-in charging of the Wuben C3, as it SERIOUSLY OVERCHARGES. (or one should monitor that once the indicator turns green, immediately unplug the C3 flashlight from the USB power. Leaving it "charging" continuously will charge to TOO HIGH voltage.
I hope this may only be a fluke with the charging of the Wuben C3 unit that I got. Can someone else who has the Wuben C3 verify? (try charging an unprotected 18650 battery), and leave the flashlight charging even after the indicator already turns green).