You can use an 18-watt charger
Apple 8plus supports up to 18W fast charge, and the charging power remains at about 15W after stability;
Apple 8plus, the use of fast charge within 30 minutes can charge 50% of the fastest, Apple 8plus mobile phone's original charger is 1A5W, now there is no own fast charger, you need to buy their own purchase.
About 15W
It should be noted that in addition to a charging head that supports USB PD fast charge, the iPhone 8 trigger fast charge protocol also requires a USB-C to Lightning data cable