BT56 MeiZu MX5 Pro Compatible Battery 3.8V 3000mAh

MeiZu MX5 Pro / NIUX Series — 3.8V Li-Polymer Replacement Battery (BT56)

This is a 3000mAh 3.8V Li-Polymer replacement cell for the MeiZu MX5 Pro, NIUX, M576, and M576U smartphones. It replaces OEM part number BT56 when the original cell has degraded, fails to hold charge, or causes unexpected shutdowns. Capacity is 11.4Wh — matching the original cell spec.

• MX5 Pro / NIUX platform fit: The M576 and M576U share the same battery bay geometry, connector pinout, and BMS handshake as the MX5 Pro and NIUX. All four models accept the BT56 cell without modification.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on an M576 board. The BMS accepted the cell on first connection, protection thresholds triggered correctly at low voltage, and the fuel gauge IC began tracking state of charge within one full cycle.
• Fuel gauge recalibration on first use: After fitting this cell, disable fast charging and run one full discharge-charge cycle at standard current. The MX5 Pro's fuel gauge IC was calibrated to your old cell's discharge curve — giving it one clean cycle against the new cell prevents erratic percentage readings and early-shutdown errors before fast charging pushes high current into an uncalibrated cell.

Sudden shutdown at 20–30% on the MX5 Pro after a cell swap

This is a voltage cliff problem, not a capacity problem. Under heavy modem activity or screen-on load, the new cell's voltage drops faster than the fuel gauge IC predicts — because the IC is still running the discharge model from the degraded original cell. When the voltage dips below the protection threshold, the BMS cuts power even though the percentage display reads higher. One full discharge-charge cycle at standard current forces the coulomb counter to rebuild its model against the actual new cell curve. After that cycle, shutdowns at 20–30% should stop.

MeiZu MX5 Pro not powering on after the battery sat discharged in storage

Li-Polymer cells in storage self-discharge over weeks. If the cell voltage drops below approximately 2.5V, the BMS enters lockout to prevent damage and blocks normal charging. The phone will show nothing on screen and will not respond to the power button. To recover it, connect a known-good charger and leave it for 20–30 minutes without attempting to boot — this lets the charge IC trickle current into the cell until it clears the BMS lockout threshold. Once the cell reaches around 3.0V, the BMS re-initialises and normal charging resumes.