/ Fundamentals /
The more current can flow, the faster the battery is charging.
The USB Port (2.0) was actually only specified to 0.5A (a consumer can always draw 100mA; after he has logged on to the host 500 mA). Any device may no longer be found. To use chargers with higher power output, however, is signaled via the data lines not used the mode "Take everything that is there - I'm a Charger" via a resistor
/ End the basics /
Unfortunately, it depends on many factors, how much charging current for example a mobile decides to take must. The cable is very strong in the issue. Cheap cables with high resistance to usually do not allow charging beyond 500mA. Even poor connections reduce the charging pleasure. These cables make sure (by a bridge and a overall low internal resistance), the mobile device removes the maximum current. If my measurements with a USB power meter and also an external multimeter (anchor, Aukey) and Power Banks were (same company) reaches the maximum current with all lengths of these cables of different chargers.
Some cheap "Lotter cable" did not make it.
Tip: Since the cable to establish data link, you should select. I have attached colored cable tie around one end. So they remain distinguishable from normal USB cable.
I used to remeasuring: PortaPow USB Power Monitor power meter / power meter digital multimeter ammeter