Pixel 9a battery 'feature'

username12354

According to the official help page,

Battery health assistance
For Pixel 9a:

Lithium-ion batteries are consumable components that eventually require replacement. Your Pixel 9a will receive a software update that automatically helps manage the long term health and performance of its battery as it ages. This software will adjust the battery’s maximum voltage in stages that start at 200 charge cycles and continue gradually until 1000 charge cycles to help stabilize battery performance and aging.

You may notice small decreases in your battery’s runtime as your battery ages. Battery health assistance will also tune the phone’s charging speed based on adjusted capacity. You may notice a slight change in battery charging performance. Battery health assistance settings on Pixel 9a aren’t customizable by the user.

Does GrapheneOS implement this? Or is it something that is going on at a level of hardware below the OS?

de0u

username12354 I believe counting of charge cycles is done by s microprocessor inside the battery that also decides when charging is over, monitors for thermal runaway, etc.

So I can imagine that the code running on that microprocessor might be updated. Many parties could do it, but I suspect the bootloader might be a good place to handle updating the battery firmware.

The 9a battery is large, I think? Personally I am happy about the precautions taken to reduce the number of lithium-ion battery fires, which are pretty fierce. The larger the battery is the more important it is for it to not go critical.

username12354

I agree, I actually don't have a big problem with this feature. Anything that makes my phone with 7 years of security updates last longer is better. But I am still confused: if I install Graphene, will my phone do this?

de0u

username12354 But I am still confused: if I install Graphene, will my phone do this?

A quick look online seems to turn up many people quoting a tiny piece of text that discusses a feature that hasn't been released yet. I think there's a fair chance that people will report on how it works after it ships.