About this replacement
Lenovo ThinkPad T590 / T15 — 11.25V Li-Polymer Replacement Battery (02DL009)
This is an 11.25V, 4800mAh (54Wh) Li-Polymer battery for the Lenovo ThinkPad T590 and ThinkPad T15 series laptops. It replaces a broad range of OEM part numbers including 02DL009, L18M3P71, L18M4P73, and SB10K97646 among others. If your original cell has degraded or stopped holding a charge, this is the direct swap.
- ThinkPad T590 and T15 platform fit: The T590 and T15 Gen 1 share the same battery bay geometry, connector pinout, and BMS handshake protocol. Lenovo used multiple OEM part numbers across production runs — L18C3P71, L18M3P74, L18S3P71 and others — but all draw from the same 11.25V three-cell architecture. This battery covers the full range.
- Bench tested on actual hardware: We ran this cell on a ThinkPad T590 and monitored BMS communication through the charge cycle. The protection circuit responded correctly to charge termination, thermal limits, and discharge cutoff. BIOS battery status populated without errors after a learn cycle.
- First-cycle calibration on ThinkPad: After installing, run one full discharge down to hibernate-cutoff, 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 hardware.
Why ThinkPad BIOS reports poor battery health right after a new cell install
The ThinkPad BIOS stores historical charge data in EEPROM on the battery's fuel gauge IC. When you swap the cell, that stored data no longer matches the new cell's actual capacity. The BIOS reads the mismatch and flags the battery as degraded or unknown. Running one full discharge-to-hibernate followed by a full uninterrupted charge lets the fuel gauge IC re-baseline against the new chemistry and clears the health warning.
ThinkPad T590 shutting down at 20–30% battery shown
This happens when the cell voltage drops below the BMS cutoff threshold under combined CPU and display load — even though the OS gauge still shows charge remaining. The fuel gauge IC maps percentage to voltage using historical data from the old cell, so the calibration is off after a swap. The fix is a full calibration cycle: discharge to automatic hibernate, then charge to 100% without interruption. After two to three cycles, the OS percentage and actual cell voltage align at around 3.2–3.4V per cell at low charge.