My answer to What Is Quick Charge 3.0?
Answer by Allen He:
For heavy users of mobile phone or other electric devices, charging their devices anytime and where seems super important. But one thing more essential is to charge devices quicker. Therefore Quick Charge technology came into the market and developed to Quick Charge 3.0 recently.
If you’re new to the concept of quick charging, the result is in the name: your smartphone charges up faster than it would without Quick Charge technology. Qualcomm boasts a fourfold increase in charging times over conventional chargers with Quick Charge 3.0, up from the 40 percent speed increase offered by its first generation technology. However, one of the interesting things to note is that Qualcomm isn’t touting massive increases in charging times over version 2.0, instead the company is focusing on improved efficiency this time around.
The major new feature with 3.0 is INOV (Intelligent Negotiation for Optimum Voltage), which allows for a fined tuned power output and a more optimized charging cycle. Firstly, different batteries require different charging voltages. Version 2.0 supported four modes at varying power levels, 5 volts/2amps, 9V/2A, 12V/1.67A, and a 20 volt option. Quick Charge 3.0’s INOV communicates with the device to request any voltage between 3.2V and 20V at 200mV increments, allowing for a wider selection of voltages.
INOV has the added benefit of being able to dynamically adjust the charging voltage over the battery charging cycle. As a battery charges up, it slowly draws less and less current, which is partly why it takes longer to charge the last 20 percent than the first. Qualcomm states that its new technology allows the phone to request just enough voltage to reach the desired charge current, thereby maximising efficiency.
This is useful as it reduces the amount of energy wasted during charging. Previously, extra power not used to charge the battery would be lost as heat, warming up your phone and reducing the longevity of the battery. By exerting more control over charging efficiency, less power is wasted, resulting in less heat. Qualcomm states that version 3.0 is up to 38 percent more efficiency than 2.0, which is a substantial energy saving.
Energy efficiency is really the major new feature with Quick Charge 3.0, but this is still very important as cooler batteries will last longer than hot ones.