The difference in charging speed between 20W and 15W is not very large, but the specific charging time difference will vary depending on the charger and charging device.
Under normal circumstances, a 20W charger charges faster than a 15W charger, which can be about 10-20% faster. For example, if a device needs to be charged for 2 hours with a 15W charger, it will take about 1 and a half hours to be fully charged with a 20W charger.
It is important to note that not all devices support 20W fast charging, and if you use a 20W charger to charge a device that does not support fast charging, it will not charge faster than a 15W charger. Therefore, when choosing a charger, be sure to choose a charger that is compatible with the device to get a better charging effect.
There is not much difference in charging speed between 20W and 15W. 20W is only a 33% improvement over 15W, and in most cases users will hardly feel the difference. In addition, the speed of the charging speed is also related to the charging device and battery capacity, if the battery is close to full state, then whether the use of 20W or 15W adapter, the charging speed will be greatly reduced. In short, although the charging speed of 20W is faster than 15W, the impact on the charging time is not particularly large, and the user can choose the adapter suitable for his device.
18w 20w charging These two are generally 9v2a and 5v4.5a, that is, 18w and 22w fast charging. It's a quarter faster than the former.For example, OPPO's VOOC evolved to SuperVOOC, and the charging power soared from 22W\/20W to 50W; Huawei\/Honor SuperCharge increased from 22.5W to 40W; vivo's dual-engine flash charge has also been increased from 18W in the past to 22.5W, and the new iQOO has brought 44W charging power; The Mi 9 is also not satisfied with the traditional 18W, and the trend has increased to 27W.