BH6X Motorola A954 Replacement Battery 3.7V 1800mAh

Motorola A954 / Atrix 4G / Droid X2 — 3.7V Li-ion Replacement Battery (BH6X)

This is a 3.7V, 1800mAh Li-ion replacement cell for the Motorola A954, Atrix 4G, Droid X2, and MB860. It uses OEM part numbers BH6X, SNN5880A, and SNN5880. The battery slots into the original compartment and connects to the same charging circuit as the factory cell.

• A954 / Atrix 4G / Droid X2 compatibility: These models share the same 3.7V single-cell architecture, identical connector pinout, and the same BMS handshake protocol — one cell fits all listed variants without modification.
• Bench tested on actual hardware: We cycled this cell on the Atrix 4G platform and confirmed the BMS accepted charge from the onboard charge IC without flagging a fault, completing full charge cycles at the rated 3.7V nominal.
• Fuel gauge recalibration on first use: After fitting this cell, disable fast charging and run one complete discharge down to auto-shutoff, then charge uninterrupted to 100%. This gives the fuel gauge IC a clean discharge curve to calibrate against before high-current cycles begin.

Sudden shutdown at 20–30% on the Droid X2 and Atrix 4G after a cell swap

The fuel gauge IC on these Motorola platforms was calibrated to the discharge curve of the original aged cell — not a fresh one. When the new cell hits a voltage region the IC hasn't mapped, it reads it as critically low and triggers a protective shutdown. This usually appears at 20–30% reported charge and happens most often under modem or screen load. Running one full discharge-to-shutoff cycle followed by an uninterrupted charge to 100% resets the coulomb counter and clears the premature cutoff behaviour.

Phone won't power on after the replacement battery sat in storage

Li-ion cells self-discharge at roughly 2–3% per month in storage. If this battery dropped below 2.5V per cell before installation, the BMS enters lockout mode and blocks current flow to protect the cell from damage. The phone will show no response — no charging animation, no boot. Connect the device to a wall charger rather than USB from a PC, leave it for 20–30 minutes without pressing anything, and the BMS should exit lockout once the cell climbs above the recovery threshold of approximately 2.9V.