New Battery Bypass feature in GOS?

qp5235

With the latest update, the stock OS now apparently supports a new Battery Bypass feature, which apparently allows to power the device directly and continuously from an external USB power supply only, without drawing power from the battery and without charging the battery (once the battery is charged to 80%):

Is this new Battery Bypass feature also available on GOS?

Rizzler

Its not here as of now. But since the firmware supports this, its possible to implement. Maybe when Graphene implements the charge limit feature eventually, they could do it this way.
I suspect the charge limiter will be done in under a year but don't quote me on this.

missing-root

I thought this was A not an OS feature (embedded controller or something) and B already there?

If not, is this (often quoted) blog post partly incorrect?

https://akc3n.page/posts/battery-management/

@akc3n

Rizzler

missing-root Yes the firmware will slow down battery degradation but some users would prefer to set a manual limit of about 80% to further slow down degradation. On StockOS it seems when the device reaches 80%, the charger will begin pass power directly to the motherboard, without going through the battery.

IcyScroll

Dumdum Thanks Dumdum, I was about to post it.

Our feature will support bypass charging too. That's already there, there just isn't configuration for it.

My guess is that bypass charging already works but only after device reaches 100%

That reasoning seems to fit blog post mentioned by missing-root

Not only that, but when your phone’s battery is reported at 100% and charging, the battery enters idle maintenance, which ensures that the battery is not going to self-discharge, without overcharging it. In this state, the phone can remain on and be powered off external power from USB, rather than using the battery. This is important to the health of your battery by reducing the amount of demand you’re placing on it.

qp5235

This forum thread is not necessarily about the new 80% charging limit.

It's mainly about the new battery bypass feature (which seems to be tied to the new 80% charging limit though), i.e. is about powering the device directly and continuously from an external USB power supply only, without drawing power from the battery and without charging the battery, i.e. without going through (aka with bypassing) the battery.

This feature would be very useful and important for using things such as desktop mode or hotspot/tethering for example, as it should allow to use those without impacting the battery at all.

According to some reports on the Internet, this new feature seems to require installing both the latest stock OS version as well as the latest Google Play System Update?

Does this mean that the feature is also available on GOS when installing Sandboxed Google Play Services?

And will it ever be available on GOS without installing Sandboxed Google Play Services?

Dumdum

Comments from GrapheneOS Mastodon account:
https://grapheneos.social/@GrapheneOS/113646936299250612

qp5235

IcyScroll

My guess is that bypass charging already works but only after device reaches 100%

Not according to: https://www.androidauthority.com/phones-with-bypass-charging-support-3509066/

spl4tt

So as far as I understand from the mastodon post, we already have the bypass charging feature? That's quite amazing.
For me, this is lifechanging. I never charge over night, as I thought it would charge between 99 and 100% all night long

qp5235

@GrapheneOS

Does the battery bypass require the use of a USB-C Power Delivery charger with PPS (Programmable Power Supply) feature support?

Or does it work with any USB power source?

Samsung devices apparently require the use of a USB-C Power Delivery charger with PPS feature for the battery bypass (called "Pause USB Power Delivery" on Samsung devices) to work.

pwmsensitive

qp5235 battery bypass (called "Pause USB Power Delivery" on Samsung devices)

Samsung should have named the Feature: 'Pause Charging to prevent heating while gaming' since the PD isn't paused.

Quote: ‘Pause USB Power Delivery’ mode is a function that operates only during the game, and is disabled and switched to battery charging state when the device operates another task than the game.
https://www.samsung.com/ae/support/mobile-devices/what-is-pause-usb-power-delivery-feature-and-how-to-use-it/

qp5235

qp5235

@GrapheneOS

Does the battery bypass require the use of a USB-C Power Delivery charger with PPS (Programmable Power Supply) feature support?

Or does it work with any USB power source?

Samsung devices apparently require the use of a USB-C Power Delivery charger with PPS feature for the battery bypass (called "Pause USB Power Delivery" on Samsung devices) to work.

In the following random example video, the power meter seems to indicate that the phone is essentially constantly drawing around 8 Volts from the PPS power supply when using the battery bypass mode:

https://www.youtube.com/watch?v=YvAWT-zIWhQ

Maybe this is because batteries typically output around 3.7 to 4.2 Volts and therefore maybe a phone still requires this voltage range when bypassing the battery. Maybe in this case the phone has a built-in voltage step down converter to half the around 8 Volts to around 4 Volts to then constantly operate at around 4 Volts in the battery bypass mode.

That maybe could explain why a PPS compatible USB-C power supply is required for the battery bypass. Because only PPS compatible power supplies are able to output variable and dynamic inbetween voltage values, whereas non-PPS power supplies are limited to fixed voltage values such as 5 Volts and 9 Volts for example.

Maybe someone can clarify if Pixel devices also require a PPS compatible power supply for the battery bypass feature to work.

trilogy6202

qp5235 Thanks for sharing. Here's a snippet from the article:

Google: The Pixel 9 series going back to the Pixel 6 supports bypass charging as of Google’s December Feature Drop update. Ensure you’ve downloaded any available updates on your phone, and head to Settings > Battery > Charging Optimization. Enabling “Limit to 80%” will ensure that your phone doesn’t charge beyond 80%, even when plugged in. You cannot use bypass charging at 100% or other charge levels at this time.

Can anyone from the GOS team confirm or reject whether it works in this way on GOS

trilogy6202

Does anyone know what this comment from @GrapheneOS on mastodon means?

@colonel Our feature will support bypass charging too. That's already there, there just isn't configuration for it.

Since Bypass Charging on stock OS is linked to the "limit charging at 80%" option, this comment is quite confusing. Does it mean that there is already a hard-coded, hidden feature to bypass charging in the currently released GOS and if so will it bypass at 100% or what does that comment mean exactly?