http://forums.hardwarezone.com.sg/h...ergy]-battle-multi-port-chargers-5212612.html
You can read my thread about how things gets charged.
One thing to note. Chargers that are rated 3A, 5A or more does not equate that it will charge any device at whatever the charger is rated at.
Smart devices will only take what is rated for the manufacturer battery.
Example, a Quick charge 2.0 device such as Samsung S6, its battery is able to charge at a maximum voltage of 9v & 1.67A. If there is no quick charge charger, it will only take in 5v & 1.73A.
No matter what charger you put, example a traditional 5v 2.1A charger, it will only charge at 5v 1.73A. It will not pull 2.1A.
However there are some devices that will take 2.1A. Such devices are like the iPad Mini, iPad...
The current new standard is USB Type C, which can go up to 5v 3A. Its objective is to fast charge just like Quick charge 2.0. But Type C cables are meant to widthstand high output current. Unlike Type A which could only take in max 2.4A.