Usb pd manufacturers said that ordinary charging means ordinary charging, and fast charging means fast charging.
1. Usb pd manufacturers say that fast charging is a relative speed standard. For mobile phones with small batteries, maybe 10W charging power can charge more than 60% in half an hour, even if it is fast charging; and for mobile phones with large batteries, maybe 15W charging power can not make it charge 60% in half an hour. Still not fast charging.
2. The usb pd manufacturer stated that the charging capacity of more than 60% in 30 minutes refers to the actual power to the battery, not the standard power of the charger. Due to the loss of charging, the charger is marked with 5V/2A, which is the charging power of 10W. The actual conversion may only be 9W of charging power.

According to usb pd manufacturers, the differences between fast charging and general charging mainly include: current, charging time, and temperature.
1. Current: Fast charging uses a current of 30%C to charge the battery, while normal charging uses a current of 10%C to charge the battery.
2. Charging time: Fast charging takes less time to complete a single charge than normal charging, and the charging efficiency is higher.
3. Temperature: The usb pd manufacturer said that the fast charging has a higher current and a faster charging speed, so the temperature of the battery rises faster during the charging process, and it is easy to heat up. The general charge current is relatively small, so the temperature rises slowly, and the safety is more guaranteed.