About this replacement
Lenovo ThinkPad T450 / X240 Series — 11.4V Li-ion Replacement Battery (45N1110)
This 11.4V, 2000mAh (22.8Wh) Li-ion cell replaces the internal battery in the Lenovo ThinkPad T450, T440, K2450, and X240 Touch. It matches OEM part numbers 45N1110, 45N1112, 45N1113, 45N1108, 45N1109, and 45N1111. Physical dimensions are 161.23 × 76.96 × 7.14mm — confirm clearance before ordering on non-standard chassis variants.
- T440 / T450 / X240 platform compatibility: These models share a common 11.4V three-cell battery rail and the same connector pinout and BMS handshake protocol. One cell SKU covers the full platform without firmware conflicts.
- Bench tested on actual hardware: We cycled this cell through the T450's charge controller. The BMS accepted the cell without error codes, held the charge curve within spec, and the protection circuit tripped correctly at low-voltage cutoff under a simulated CPU-plus-display load.
- Post-install discharge cycle on ThinkPad: After fitting this cell, run one full discharge to Lenovo's 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.
BIOS reporting battery health as poor immediately after swapping the T450 cell
The ThinkPad BIOS reads health data stored in the cell's EEPROM, not from live voltage measurements. A new cell ships with factory EEPROM values that don't match the BIOS's learned charge history from the old cell, so the system flags it as degraded. This is not a fault with the replacement cell. Run Lenovo's Battery Gauge Reset under Power Manager, or complete one full discharge-to-hibernate then an uninterrupted charge to 100%. After one to three full cycles the BIOS recalibrates and the warning clears.
ThinkPad T450 shutting down at 20–30% charge shown on screen
This happens when the fuel gauge IC's capacity map no longer matches the actual cell chemistry — common after a cell swap and also seen on aged originals. Under combined CPU and display load, the cell voltage drops faster than the old calibration predicts, hitting cutoff voltage while the OS still shows significant charge remaining. The fix is the same learn cycle: discharge fully to hibernate cutoff, then charge to 100% without interruption. Repeat two to three times until the reported percentage aligns with actual cutoff — confirmed when shutdown no longer occurs above 5–8% remaining.