Android 15 is preparing to tweak the threshold that determines whether a charger is seen as fast, from 7.5W to a more reasonable 20W.
TL;DR
Android 15 is preparing to tweak the threshold that determines whether a charger is seen as fast, from a measly 7.5W to a more reasonable 20W.
The operating system has long considered any charging speeds of at least 7.5W to be fast, which is far, far below what actual fast chargers can deliver nowadays.
The change isn’t live yet in the latest Android 15 beta, though, so chargers that deliver 7.5W of power will still be seen as fast on Pixels.
below 5W, then the charger is considered “slow,” and the message “charging slowly” is shown on the lock screen. If the power is above 7.5W, then it’s considered “fast,” and the “charging rapidly” message is shown instead. If the power is between 5 and 7.5W, then the charger is seen as “normal,” and the lock screen simply says the phone is “charging.”
Seems to be a purely cosmetic change. I was wondering if the OS has any different behavior when charging quickly (like being more aggressive with running background processes, and running updates/backups) but the article didn't say anything about that.
If my phone was only charging at 5 or 6W I'd want to know the charger is garage. That might not even be enough to use the phone without losing battery. What they really need is to rename "slow" to "very slow", and then 5W to 7.5W could be considered the new "slow". The intent being that "very slow" is problematically slow (maybe the OS scheduler could pretend the phone is not charging). And "slow" charging would just be for mild inconvenience.
If only the phone could just tell me the actual number of watts it's charging at lol. Even if it's rounded and averaged.
iirc, there are currently 3 charging states: Fast, Slow, and Low Power Charger, which already covers your cases, so I would argue just moving the bar between low and high up is probably enough.
I've only ever seen it when running a game or when a chromebook got plugged into a 5w charger, so I'm guessing it's when the OS does the math and decides it can't rev down enough to make headway while booted up.
It's also possible to have voltage issues on a device with multi-cell batteries.
My laptop charges on a type-C charger, but only if it can get 15+ volts. If it's a 12V charger, that isn't enough to push a charge into its battery. It will run on 12V but won't charge at all, even if it's off.