Lenovo ThinkPad T490 Replacement Battery 11.52V 4250mAh

Lenovo ThinkPad T490 — 11.52V Li-Polymer Replacement Battery (02DL007)

This 11.52V, 4250mAh (48.96Wh) Li-Polymer battery is a direct cell replacement for the Lenovo ThinkPad T490 and T490-based variants including the P43s. It matches the original three-cell pack geometry at 257.18 × 99.12 × 6.20mm and uses the same connector and BMS interface as the factory unit.

• T490 and P43s compatibility: Both the T490 and P43s share the same 11.52V three-cell Li-Polymer architecture, identical connector pinout, and the same BMS handshake protocol — which is why they draw from a single battery platform across OEM part numbers including L18C3P73, L18L3P73, L18M3P73, and L18S3P73.
• Bench tested on actual hardware: We ran this cell on a T490 unit and confirmed the BMS communicates correctly with the EC — charge current accepted at full rate, no fault codes thrown, and the pack cycled cleanly through charge and discharge without cell balancing errors.
• BIOS learn cycle after install: After fitting this battery, run the T490 down to hibernate cutoff on battery power alone, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning that appears after every cell swap on ThinkPad firmware.

BIOS reporting poor battery health immediately after replacement

ThinkPad firmware stores battery health data in EEPROM on the old cell. When a new cell is installed, the BIOS reads stale EEPROM metrics and flags health as poor or unknown — this is a firmware artefact, not a fault with the new battery. The EC needs at least one full discharge-to-hibernate and uninterrupted recharge cycle to write fresh calibration data against the new cell's actual charge curve. After that cycle, Lenovo Vantage and the BIOS battery report should update to reflect accurate health. If the warning persists beyond two full cycles, check that Vantage firmware is current.

T490 shutting down abruptly at 20–30% remaining

This happens when the cell hits a voltage cliff — under full CPU plus display load, cell voltage drops faster than the fuel gauge IC can track, and the system shuts down before the displayed percentage reaches zero. It is common on cells that have not yet completed a full calibration cycle after installation. Run a full discharge to hibernate cutoff with the screen at full brightness and a CPU load applied — this forces the fuel gauge IC to map the actual voltage-to-capacity curve of the new cell. After one complete calibration cycle, the shutdown threshold should stabilise at or below 5%.