Poco M3 BN62 Compatible Battery 3.85V 5700mAh

Poco M3 / M2010J19CI — 3.85V Li-Polymer Replacement Battery (BN62)

The BN62 is a 3.85V, 5700mAh Li-Polymer cell that fits the Poco M3 (model number M2010J19CI). It replaces the original battery when the existing cell can no longer hold a consistent charge or causes unexpected shutdowns. Capacity is rated at 21.95Wh, matching the original specification.

• M3 and M2010J19CI fitment: Both model references point to the same hardware revision. The BN62 uses the same connector pinout and BMS communication protocol as the factory cell, so the charge IC recognises the replacement without a firmware flag.
• Bench tested on actual hardware: We ran the BN62 through charge and discharge cycles on the M3 mainboard. The BMS accepted the cell without throwing an authentication error, and the charge IC stepped through trickle, CC, and CV phases correctly.
• Fuel gauge recalibration on first install: On first use after installation, disable fast charging and run one complete discharge-charge cycle at standard rate. This lets the fuel gauge IC map the new cell's discharge curve before high-current fast charging pushes current into an uncalibrated register.

Sudden shutdown at 20–30% on the Poco M3 after a cell swap

The Poco M3's fuel gauge IC holds a discharge curve calibrated to the original cell. When a new cell goes in, the IC's coulomb counter still references old data. Under modem or display load, the cell voltage drops faster than the IC expects, and the board interprets it as a hard undervoltage event. The phone cuts power even though the cell has charge remaining. One full discharge-to-shutdown cycle, followed by an uninterrupted charge to 100%, overwrites the old curve. After that cycle, reported percentage tracks actual cell state correctly.

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

The M3's charge IC negotiates fast charge only after it confirms the cell is within a safe voltage window and the BMS handshake is valid. On a fresh cell that has self-discharged slightly during storage, the IC may default to standard 5V charging for the first cycle as a safety hold. This is not a fault with the replacement cell. Charge the phone fully once at standard rate, then reconnect with the original fast charger. The IC re-runs the negotiation against a fully initialised BMS and fast charge resumes from the second cycle onward.