Lenovo ThinkPad P50 15.2V Replacement Battery 00NY490

Lenovo ThinkPad P50 / P51 — 15.2V Li-ion Replacement Battery (00NY490)

This 15.2V 4200mAh (63.84Wh) Li-ion battery replaces the original cell in the Lenovo ThinkPad P50 and P51 mobile workstation series. It covers OEM part numbers 00NY490 through 00NY493, SB10H45075–SB10H45078, and 01AV476–01AV477, among others. If your P50 no longer holds a charge or shuts down under load, this cell restores full battery operation.

• P50 and P51 platform compatibility: Both the P50 and P51 share the same 15.2V four-cell Li-ion battery architecture, connector pinout, and BMS handshake protocol. That's why one part number family covers both chassis — the BMS firmware reads the same EEPROM identifiers across both models.
• Bench tested on actual hardware: We ran this cell on a ThinkPad P50 under sustained CPU and GPU load. The BMS held voltage above the 12.0V cutoff threshold throughout the draw cycle, and the protection circuit responded correctly to both over-current and thermal trip conditions.
• Post-install discharge cycle on the P50: After fitting this cell, run one full discharge to hibernate-cutoff, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning that appears in Lenovo Vantage after every cell swap.

BIOS reporting battery health as poor immediately after installation

The ThinkPad P50 BIOS reads health data from the battery's EEPROM, which stores cycle count, rated capacity, and historical charge data from the previous cell. A new cell arrives with EEPROM values that don't match the system's learned discharge curve, so the BIOS flags it as degraded before any calibration has occurred. This is a data mismatch, not a fault with the battery. Run one full discharge-to-hibernate cycle followed by an uninterrupted charge to 100%, and the BIOS will re-learn the cell and clear the warning.

ThinkPad P50 shutting down at 20–30% charge shown on screen

This happens when the cell voltage drops below the BMS cutoff threshold under full CPU plus display load, even though the fuel gauge IC still reports charge remaining. The fuel gauge is reading an estimated state-of-charge, not real-time voltage — so when a cell hits its voltage cliff under high current draw, the system cuts out before the gauge reaches zero. On the P50, this is most common when running Xeon workloads or driving external displays simultaneously. After completing the BIOS learn cycle, confirm the shutdown point moves below 10% — if it persists, check that BIOS power settings are not capping discharge at a fixed voltage of 11.4V.