Android 11’s hidden Battery Share menu hints at reverse wireless charging for the Pixel 5

Android 11’s hidden Battery Share menu hints at reverse wireless charging for the Pixel 5

Today, Google released the first Android 11 Developer Preview for Pixel devices (excluding the first generation models), and we’ve in the process of detailing everything we’ve found so far. While digging into the Android 11 system dump for the Pixel 4, I noticed a new activity in SettingsGoogle, the Settings app for Pixel smartphones, called “Battery Share.” Intrigued, I launched the activity and discovered what looked to be an upcoming feature. The logo is clearly a placeholder—it’s the same one from the Adaptive Battery page—but the strings, which are new, suggest that Google is working on a reverse wireless charging feature, possibly for the Pixel 5.

Since the activity name was prefaced with “com.google.android” rather than “com.android,” this “Battery Share” activity is most likely a Google feature rather than an AOSP one. This pattern is true for other Google features such as Active Edge and Pixel Stand wireless charging, so we think we’re looking at the beginnings of Google’s reverse wireless charging feature rather than a generic AOSP implementation. The strings for the Battery Share page state that “your phone’s battery will run out faster when using battery share. Battery share works with compatible ear buds, watches, phones, and more.” While this doesn’t explicitly mention wireless charging or reverse wireless charging, the implication is clear: You’re sharing your phone’s battery, which means it’ll run out faster, with certain compatible ear buds, watches, and phones. We can assume this is referring to using your device to charge other Qi-compatible accessories and smartphones.

Android 11 Battery Share - Pixel 5 reverse wireless charging?Google’s Pixel 3, Pixel 3 XL, Pixel 4, and Pixel 4 XL support Qi wireless charging. The Pixel 3 and Pixel 3 XL support 10W wireless charging using the proprietary Pixel Stand charger, though they also support 5W Qi wireless charging on other wireless chargers. The Pixel 4 and Pixel 4 XL also support 10W wireless charging on the Pixel Stand, but Google increased the wireless charging rate to 11W for compatible Qi wireless chargers. No Pixel phone currently supports reverse wireless charging at the moment; whichever device ends up having this feature, which is likely the Pixel 5, will be the first in Google’s Pixel line to support the feature. This feature would pair nicely with the new truly wireless Pixel Buds.

We’ll continue digging into the Android 11 Developer Preview to see if we can find more information about this feature, the upcoming Android OS stable release, or the Pixel 5.

Update: Link to Wireless Charging and Pixel “Redfin” Found

While examining the Java code of the new BatteryShare feature, I discovered a method in BatteryShareSwitchPreferenceController called “setChecked” that flashes a toast message stating “can’t Battery share while charging wireless!” if the device is currently wirelessly charging. A method called isSupportedBatteryShare in BatteryShareFakeManager grabs a string array called “config_device_model_name,” which currently only holds “redfin” as its value. Redfin, if you’ll recall, is one of the new Pixel code-names we’ve been tracking. It’s an upper mid-range device with the Qualcomm Snapdragon 765. While we still don’t know exactly where this device is slotted into Google’s device line, we now know it’ll support reverse wireless charging. Could the Pixel 5 have a mid-range processor?

About author

Mishaal Rahman
Mishaal Rahman

Editor-in-chief at XDA-Developers. I follow AOSP and the Chromium Gerrit to uncover new features, and I also routinely analyze Android applications and device firmware to do the same. Tips/media inquiries: [email protected]