Pixel Owners Perplexed by Charging Pattern: 80% Threshold Feature Explained
Pixel owners are observing an unexpected battery charging behavior. The 80% charging threshold feature, designed to extend battery lifespan, appears to be ignored at times. This has led to confusion and discussion among Pixel users.
User Reports and Initial Confusion
Pixel users have reported instances where their devices charge to 100% despite having the 80% charging limit enabled. Discussions have surfaced on platforms like Reddit and Google support forums. Some users initially speculated that a March Android update might be the cause. The core purpose of the 80% feature is to prevent full charges, which can contribute to faster battery degradation over time. Consequently, observing the feature's apparent disregard is understandably concerning.
The Surprising Reason: Intentional Battery Calibration
Contrary to initial assumptions, this behavior is not a malfunction. Developers from GrapheneOS, known for their privacy-focused Android operating system for Pixel phones, clarified the situation. Pixels are intentionally designed to charge to 100% periodically, even when the 80% limit is active.
Battery Calibration: The Necessity of 100% Charges
Google implements this occasional 100% charge for battery calibration. Accurate battery percentage readings and efficient power management rely on the phone's ability to learn and track its battery capacity. To maintain accuracy, even with an 80% limit, Pixel devices recalibrate by intentionally charging to 100% on occasion. This recalibration process ensures the system accurately reflects the battery's long-term health.
Android 15 QPR2 Update and Corrected Functionality
GrapheneOS further highlighted that prior to the Android 15 QPR2 update, this recalibration mechanism was not functioning as intended. The current user experience, where the device occasionally charges to 100% despite the limit, actually indicates the system is now working correctly, as designed by Google. The perceived issue of the "broken" 80% limit is therefore part of a system designed to maintain accurate battery readings and promote long-term battery health for Pixel devices.