Google Pixel 3 XL Compatible Battery 3.85V 3000mAh G013C-B

Google Pixel 3 XL — 3.85V Li-Polymer Replacement Battery (G013C-B)

This is a 3.85V, 3000mAh (11.55Wh) Li-Polymer cell that replaces the original G013C-B battery in the Google Pixel 3 XL (G013C). It fits directly into the Pixel 3 XL chassis and reconnects to the stock charge IC and fuel gauge. Use this when the original cell has degraded, swells, or can no longer hold a usable charge level.

• Pixel 3 XL compatibility: The Pixel 3 XL uses a dedicated battery bay sized for the G013C-B cell — 77.45 x 54.04 x 4.65mm. The connector pinout carries both power and the BMS data line that talks directly to the Qualcomm PM845 PMIC. A cell outside these specs will not seat correctly or communicate with the charge controller.
• Bench tested on actual hardware: We ran this cell on a Pixel 3 XL board and confirmed the BMS handshake completed on first boot, fast charge negotiation triggered via USB-PD on the second full cycle, and the coulomb counter began tracking state of charge without error flags in the battery stats log.
• Fuel gauge recalibration on first use: On first use after installation, disable fast charging for one complete discharge-charge cycle. The fuel gauge IC on the Pixel 3 XL calibrates its discharge curve against the cell it sees — running a slow cycle first lets it map the new cell's voltage profile before high-current USB-PD charging begins pushing current into an uncalibrated curve.

Sudden shutdown at 20–30% on the Pixel 3 XL after a cell swap

This happens because the Pixel 3 XL's fuel gauge IC still holds the discharge curve from the old, degraded cell. When the new cell hits a voltage point the IC doesn't expect — typically around 3.65–3.70V under modem or screen load — the PMIC reads it as a critical low and cuts power immediately. The phone shuts down even though real capacity remains. One full slow discharge-charge cycle lets the coulomb counter relearn the new cell's voltage-to-capacity relationship and eliminates the false cutoff.

USB-PD fast charge not activating on the first cycle after replacement

After a cell swap, the Pixel 3 XL charge IC defaults to a lower current rate until it confirms BMS communication is stable. On the first cycle, the handshake between the new cell's BMS and the PM845 PMIC can take a full charge-discharge pass to complete authentication. Fast charge via USB-PD may appear absent — the phone charges slowly and the fast charge indicator does not appear in the status bar. Complete one full cycle on a standard 5W charge, then reconnect the USB-PD adapter — fast charge should negotiate correctly from 3.85V upward on the second cycle.