Every time I use the Samsung Galaxy S6 Edge, I almost feel guilty when I keep on seeing the battery go down before my eyes just after several minutes. To see if my eyes were playing tricks on me, I used the battery usage screen in the Galaxy S6 Edge's Settings to see how quickly the battery was being consumed and charged.
After waiting for the battery to almost fully discharge, I was able to get the Galaxy to report that 2% of the battery charge was left, equivalent to approximately 30 minutes. Within the same minute though, it dropped to 1% or 15 minutes remaining. That was the first "lie" from the battery usage scbut I guess it's normal that when the battery is that low the charge dies even quicker.
At this point I compared how quickly the Galaxy charged when connected through USB to a MacBook Pro versus the Samsung 5 Volts 2 Amps charger that comes with the Galaxy.
First, when connected to Samsung charger, the Galaxy reported that it would take 1 hour and 37 minutes until fully charged when the battery charge level is at 1%.
After a couple minutes, the battery charge level increased to 3% and the Galaxy reported it would take 1 hour and 36 minutes until fully charged.
At this point, I switched to charging using the MacBook Pro, and the time it took to fully charge the Galaxy at 3% increased by almost 4 times to 6 hours and 8 minutes. After 1 minute of charging, instead of taking less time, the Galaxy reported that it would now take 6 hours and 9 minutes to fully charge the Galaxy (1 minute longer than before). This long charge time is perhaps ok if you are leaving your device connected to a Mac or PC overnight but clearly too slow for a quick bump up charge during the day.
To see how accurate the Galaxy reported battery usage rate, I charged the battery to 20% and the Battery usage screen reported 5 hours and 7 minutes of battery charge remaining. However, after just 3 minutes the battery level dropped to 19% and the screen reported only 4 hours and 51 minutes left. Perhaps there was a time warp where the Galaxy lost 16 minutes of charge in 3 minutes or perhaps the Galaxy battery usage screen is just really bad at predicting how much battery charge is left.
The Samsung Galaxy S6 Edge consumes power quickly but in the future if and when Samsung adopt USB Type-C, power charging should be much faster.