Samsung SCH-A970 Replacement Battery BEX480HSAB 3.7V 1500mAh

Samsung SCH-A970 / MM-A940 — 3.7V Li-ion Replacement Battery (BEX480HSAB)

This is a 3.7V, 1500mAh Li-ion cell built to the BEX480HSAB specification for the Samsung SCH-A970 and MM-A940 handsets. It slots into the original battery bay and connects to the phone's charge IC and fuel gauge circuit. Capacity figure is 5.55Wh — taken from product data, not estimated.

• SCH-A970 and MM-A940 shared platform: Both handsets run the same battery bay dimensions, connector pinout, and BMS handshake protocol. One cell covers both devices without modification or adapter.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the SCH-A970 platform. The BMS accepted the handshake on first connection, charge IC stepped through trickle, constant-current, and constant-voltage phases without error, and the protection circuit tripped correctly at the low-voltage threshold.
• Fuel gauge recalibration on first use: After fitting this cell, disable fast charging if your carrier or ROM supports it, then run one full discharge-to-charge cycle at standard rate. The phone's coulomb counter is calibrated to the old cell's discharge curve — one full cycle at standard current lets it remap against the new cell before high-current charging resumes.

Sudden shutdown at 20–30% on the SCH-A970 after cell swap

This is a voltage cliff, not a capacity fault. Under combined modem, display, and processor load, the new cell's terminal voltage drops faster than the fuel gauge IC expects — because the IC is still reading the old cell's internal resistance profile. The phone interprets the voltage sag as a dead cell and cuts power to protect the system. Run one full discharge to near shutdown, then charge uninterrupted to 100% at standard rate. After that cycle, the fuel gauge recalibrates its slope and the premature cutoff stops.

Phone reads 100% immediately after fitting new battery — then percentage drops fast

The fuel gauge IC stored the old cell's charge state in memory and carries it forward to the new cell on first boot. It hasn't measured the new cell at all — the 100% reading is stale data. The percentage then drops quickly as the IC encounters a discharge curve it doesn't recognise. Let the phone drain down to auto-shutdown, then charge to full without interruption. That single cycle resets the coulomb counter against the actual 1500mAh cell and percentage reporting stabilises.