BLU Life OneXL C866640282L Replacement Battery 3.8V 3000mAh

BLU Life OneXL — 3.8V Li-Polymer Replacement Battery (C866640282L)

This is a 3000mAh Li-Polymer cell at 3.8V (11.4Wh) for the BLU Life OneXL smartphone and related models including the L050, LIFE XL, and Life One XL. It replaces OEM part numbers C866640282L and C866639282L. Swap this in when the original cell no longer holds a usable charge or causes unexpected shutdowns.

• BLU Life OneXL series fit: These models share the same battery bay dimensions (86.60 × 65.90 × 4.00mm), connector pinout, and charge IC handshake — the replacement cell seats and communicates with the board the same way the original does.
• Bench tested on actual hardware: We cycled this cell through a full discharge and charge sequence on the BLU platform. The BMS held charge termination correctly and did not trigger overcurrent cutoff during the modem-active draw spikes we ran.
• First-cycle fuel gauge recalibration: After installing this cell, disable fast charging and run one complete discharge down to auto-shutdown, then charge to 100% on standard current. This gives the fuel gauge IC one full reference cycle against the new cell's discharge curve before fast charge pushes high current into an uncalibrated cell.

Sudden shutdown at 20–30% on the BLU Life OneXL after a cell swap

This is a voltage cliff issue, not a capacity fault. A fresh cell has a slightly different voltage-to-capacity curve than the aged cell the fuel gauge IC was calibrated against. When the screen or modem pulls a brief high-current burst, terminal voltage sags below the shutdown threshold even though the OS still reads 20–30% remaining. One full reference cycle — discharge to cutoff, charge to 100% on standard current — recalibrates the coulomb counter and eliminates the premature shutdown.

OS percentage jumping erratically after installing the replacement cell

The fuel gauge IC on the BLU Life OneXL stores a learned model of the original cell's impedance and discharge slope. A new cell has different internal resistance, so the IC's state-of-charge estimates swing wide until it gathers real data. You will see percentage jump up or drop several points with no load change. Run two full discharge-to-100% cycles without interruption and the readings stabilise — the IC rewrites its reference model by the end of the second cycle.