How does the quick charge feature work on my Xperia?

Solution

Your Xperia phone supports USB Power Delivery and works as below. 

• When using a PD charger (attached charger) with 30W output in a 25 ° C environment/screen off state, it can be charged fastest (50% after 30 minutes from 0% start). 
• After the battery capacity is 50%, the charging current will be gradually reduced to protect the battery, so the charging speed will be slower. 
• Charging while operating the device may slow down the charging speed due to heat generation control. 
• When the device is powered on, background operation may affect the charging speed, so charging may be faster when the device is powered off. 
• If the charger has a low supply capacity (5V charger, etc.), the charging speed will be slower. 
• If you operate the device while charging with a charger with low supply capacity (5V charger, etc.), it may not be charged, or the battery level may be reduced. 
• In a high-temperature environment, charging is restricted for safety, charging speed may be slow or charging may stop. 
• In a low-temperature environment, charging is restricted for safety, and charging speed may be slow or charging may stop. 
• If the supply capacity is low or the device operation is consumed for a long time and the charging time is prolonged, charging will be forcibly terminated. 
• If the battery level becomes 0% and the time elapses after shutting down, it may take some time before it can be started by charging.