Summary:
+ Handy
+ The 4 blue LEDs for charge status display are not obtrusive light
+ Power Bank shuts off when the connected device is charged
+ Power Bank only supplies current when the button is pressed
+ Super bright LED
- The 4 LEDs (and thus the Power Bank) switch / herself does not switch off when the Power Bank is charged (keyword overcharge protection)
- Charging indicator might be more accurate
- Real capacity unclear (see below)
I use a Samsung Galaxy S2 with a 1,800 mAh battery of Mumbi (the original had 1,650 mAh). Furthermore, I use a Samsung Wave S8500 with an original 1,500 mAh battery.
-> My previous calculations are based on information of these batteries! it would be more accurate to tap into a USB meter current and voltage.
Now to the actual review :-)
is included next to a very short and a short USB A / B--micro - cable and a lanyard that can be attached to the Power Bank. This can be useful - an envelope I could but found better!
the manual is good and explains the basic features, including the various levels of the battery LED indicator.
LED display in the instruction manual:
OOOO 75% -100% (all LEDs on)
OOOX 50% -75% (fourth LED off)
OOXX 25% -50%
OXXX 5% -25%
OXXX 0% -5% (first LED is blinking)
the first time I could not even charge two times my S2. I know the exact values anymore, but I could roughly averaged charge of 5 to 95 percent. were the means that only 0.9 * 1,800 * 2 = 3,240 [mAh] transmitted ... what ?! that would be an efficiency level of 36%!
the second attempt is not yet finished. until now I could charge my S2 twice from 4% to 100%. However, the first LED flashes for the Mobile Phone Battery last time was 12% displayed. it took me quite a bit shocked that I still could once fully charge the S2. that's why I immediately afterwards even the Wave I with 14% remaining charge drangehängt and it was fully charged.
Bill:
Assumption: discharge of phone battery about 4% / h (which the Wave I is neglected, since no wireless connections were active)
Charging time: 3.5 hours
-> 0.96 * 1,800 * 2 + 0.04 * 1,800 * 3.5 * 2 + 0.86 * 1,500 = 5,250 [mAh]
which corresponds to an efficiency of only 58%, which is, after all, somewhat higher than the first time. Nevertheless, this value is still underground! I am the Power Bank still completely discharged (perhaps it still creates so a battery with allegedly 0-5 percent charged ;-)) and fully charge it to launch a third attempt.
what bothers me about this property is that it seems as if the battery would need to be calibrated. And I've assumed that lithium batteries actually have to go through does not provide full charging cycle. somehow it looks at the moment but from then. I would like the device also dismantle even if I did not play with the idea to let it go back. as I said update follows!