There may be some inconsistencies with the reports of Google on their phones, Google Pixel and Pixel Plus. After thorough studies and examination, charging only peaks at 15W while Pixel XL peaks at 18W.
According to GSM Arena, the charging capacity on Google Pixel is inconsistent and incorrect. After an Android Community tester performed a battery test to confirm the legitimacy of Google's claim, it was proven that Google Pixel was not charging at 18W of peak power the charger is said to perform.
Google admitted to the oversight in the description of both Google Pixel and Google Pixel XL's specification. It was indicated that both Google Pixel and Google Pixel XL plus charges at 18W peak power. It was only Google Pixel XL lives up to the specification while Google Pixel only does 15W.
It is still unconfirmed why Google limited the peak charging wattage on the smaller Pixel. However, as reported, Google have admitted to the oversight of the detail since the test has been made for Pixel and Pixel XL.
Both Pixel and Pixel XL comes with the same charger upon purchase. Google Pixel XL is the only device capable of utilizing the full wattage of 18W.
As added by Android Police, the difference between Pixel and Pixel XL's charging capacity accounts for around 20 percent speed boost at peak charging speed for the Pixel XL compared to the smaller Pixel phone. The battery of Pixel XL is larger so even at peak of 18W, it still takes longer to charge.
There are also various factors that affect the charging capacity of both Pixel and Pixel XL. It can vary on temperature whether the display is on or off. Battery chemistry is also being considered. This is considered a minor discovery and should not greatly affect the charging performance Pixel and Pixel Plus.
