Originally Posted by Goodspike
There's another thread here where I learned something new about voltage drop. I usually think of it in higher voltage, such as generator runs, but it turns out you can have significant voltage drop in 5 volt over just 3 feet if the gauge of the wire is not sufficient. As I recall, you should have 24 gauge wire, where many USB cables are 28 gauge.
Anyway, not terribly up on battery charging, but I would suspect a voltage drop would significantly impact charging times.
You are correct on this. I've tried using old chargers, that are less then the 2.0 amp on the S4 stock charger. (They take like 3 hrs from about 20% battery left.) I can charge my phone from 10% battery left to 100%, in sleep mode, in just under 2 hrs. Considering how big the battery is, the stock charger charges really fast.