BLU Grand XL C906428265L Replacement Battery 3.8V 2300mAh

BLU Grand XL / G150Q — 3.8V Li-ion Replacement Battery (C906428265L)

This is a 3.8V, 2300mAh Li-ion battery for the BLU Grand XL and G150Q smartphones. It replaces OEM part number C906428265L. The battery fits the internal bay on both models and connects through the standard BLU flex connector.

• Grand XL and G150Q compatibility: Both models run the same 3.8V power rail and use the same physical connector and BMS handshake protocol. One cell covers both. The PCB protection circuit matches the charge IC expectations on each board.
• Bench tested on actual hardware: We ran this cell through full charge and discharge cycles on BLU Grand XL hardware. The BMS accepted charge input without fault flags, and cell voltage held stable through screen-on and modem-active load conditions.
• Fuel gauge recalibration after installation: After fitting this cell, run one complete discharge down to auto-shutdown, then charge uninterrupted to 100% before use. The Grand XL's fuel gauge IC was calibrated to your old cell's discharge curve — one full cycle rewrites that baseline against the new cell.

Sudden shutdown at 20–30% on the BLU Grand XL after a cell swap

This is a voltage cliff issue, not a capacity fault. A new cell has a different discharge curve than the degraded cell the fuel gauge IC learned. When the phone reads 25% on the old curve, the actual cell voltage may be closer to 3.5V — low enough that modem or display load pulls it below the BMS cutoff threshold instantly. The phone shuts off to protect the cell. One full discharge-to-shutdown followed by a complete uninterrupted charge retrains the coulomb counter and eliminates the false cliff. After that cycle, percentage readings stabilise above 3.6V per cell.

Phone won't power on after the replacement battery sat in storage

Li-ion cells shipped or stored at low state of charge can drop below 3.0V per cell during extended shelf time. At that level, the BMS enters lockout mode and blocks current flow to prevent damage — the phone shows no response even when plugged in. Connect the device to a wall charger, not a USB port, and leave it for 20–30 minutes without pressing any buttons. Wall adapters deliver enough trickle current to push the cell back above the 3.0V re-enable threshold, at which point the BMS releases lockout and normal charging resumes.