A: Charging the 20W Fast Charge xr takes 5 seconds to full 100 joules. According to the electric work formula W=Pt. The formula results in t=W\/P=100 joules \/20 watts =5 seconds. It's probably some kind of phone charger. Different models of mobile phone chargers are different. Don't mess with the charger when charging the mobile phone. Must match the phone model. Otherwise it will damage the phone. Mobile phone charging is best off charging and.
Apple Fast Charge 20w full takes about 2 hours 30 minutes. Of course, depending on the health state of the battery, the charging time is relatively short.