Meu AN500 Replacement Battery 3.7V 2000mAh Li-ion

Meu AN500 — 3.7V Li-ion Replacement Battery

This is a 3.7V, 2000mAh Li-ion replacement battery for the Meu AN500 smartphone. It slots into the original battery bay and restores power to calls, messaging, and apps. No OEM part number is published for this cell, but dimensions (70.18 × 60.00 × 4.67mm) match the AN500 battery compartment.

• AN500 fit confirmation: The AN500 uses a single-cell 3.7V Li-ion configuration with a connector pinout that carries both power and fuel gauge data. The replacement cell shares the same physical footprint and pin arrangement, so the phone's charge IC accepts it without hardware modification.
• Bench tested on actual hardware: We cycled the cell through charge and discharge on the bench, monitoring BMS cutoff behaviour at both the high-voltage and low-voltage limits. The protection circuit tripped correctly at the low-voltage threshold and resumed charging without error after reconnection.
• Fuel gauge recalibration on first install: On first use after installation, disable fast charging for one complete discharge-charge cycle. This lets the fuel gauge IC map its coulomb counter against the new cell's actual discharge curve before high-current charging begins on an uncalibrated cell.

Sudden shutdown at 20–30% on the replacement cell

A new cell has a slightly different internal resistance profile than the original. Under peak load — active call, screen on, mobile data transmitting — the phone draws a short burst of current that causes a voltage dip. If the fuel gauge IC is still calibrated to the old cell's curve, it misreads the remaining capacity and the BMS shuts down the phone before the gauge hits zero. One full discharge-charge cycle after installation corrects the reference table the fuel gauge uses. After calibration, the shutdowns stop.

Phone reads 100% immediately after install and drops fast

The fuel gauge IC on the AN500 stores a charge state from the previous cell. When a new cell is installed, the IC inherits that stale reading rather than measuring the actual state of charge. The percentage then jumps or drops erratically until the coulomb counter resets through a full cycle. Drain the phone completely until it powers off, then charge uninterrupted to 100% — after one full cycle the gauge tracks the new cell correctly.