When the Google Pixel 2 XL was first announced it was thought that it would support a massive 27W charging speed but unfortunately according to Benson Leung they will only support 18W. Now, another analysis has surfaced showing that it supports a LOT less.
Google+ USB analyst Nathan K. has checked out the Pixel 2 XL on the “18W” charger shipped by Google with the phone and found it to be functioning at well below expected levels. Using the 15/18W OEM charger for the Google Pixel 2 XL he found that the charging was capped at just 10.5W and then once the battery reached 65% the charging speed dropped exponentially.
Nathan K. suspects this may be due to Google or LG trying to prolong battery life given the battery degradation issues the Nexus 6P (and many Pixel 1) owners are experiencing. The conservative charging speed will result in the battery seeing much lower temperatures as seen below.
The end results show that the maximum temperature the battery is set to reach while charging is 32.6 degrees Celcius with the charging speed capped at 10.5W — a fair way below the 15W/18W charger that ships with the phone. Interestingly the phone does “hog” 27W (9 volts at 3 amps) when using an aftermarket USB-PD charger such as the 87W Apple charger. Although it requests this power from the Apple charger it will never exceed 2 amps on output.
While it is not a bad thing to try to extend battery life it makes you wonder why Google included such a powerful charger with the phone if they were not going to use it. It has been suggested that there may be a Linux kernel upstream fix coming that will allow faster charging but at this stage nothing has been announced.
We are yet to hear from noted USB-C advocate Benson Leung or officially from Google so this is all speculation but one thing is definite, the Pixel 2 XL will NOT charge at the full speeds expected of it due to internal sensors.