About this replacement
Lenovo IdeaPad U260 — 14.8V Li-Polymer Replacement Battery (L09M4P16)
This is a 14.8V, 2600mAh (38.48Wh) lithium-polymer battery for the Lenovo IdeaPad U260 ultraportable notebook. It replaces OEM part numbers L09M4P16 and 57Y6601. Fits the IdeaPad U260, U260 0876, U260 0876-3DU, and U260 0876-3AU, among other U260 variants.
- IdeaPad U260 platform fit: All U260 variants share the same 14.8V four-cell Li-Polymer configuration and the same bottom-case connector footprint. The BMS handshake protocol is consistent across the 0876 sub-models, so one cell works across the entire U260 line without firmware conflicts.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on an IdeaPad U260 unit. The BMS accepted the charge from zero without interruption, balancing across all four cells as expected. No overcurrent trip or rejected handshake was recorded during testing.
- BIOS learn cycle after installation: After fitting this cell, run the laptop down to hibernate cutoff on battery power, then charge uninterrupted to 100% without booting. This resets the BIOS battery learn cycle and clears the inaccurate "poor health" warning that appears routinely after any cell swap on the U260.
Laptop shuts down at 20–30% remaining after battery swap
This happens because the fuel gauge IC on the U260 mainboard still holds calibration data from the old, degraded cell. When combined CPU and display load pulls peak current, the new cell's voltage briefly dips below the BIOS cutoff threshold — even though the state-of-charge indicator still reads 20–30%. The BIOS interprets that voltage sag as an empty cell and cuts power immediately. Running two full discharge-to-hibernate cycles re-calibrates the fuel gauge against the actual capacity of the new cell and eliminates the early shutdowns.
BIOS reporting battery health as poor or "unknown" right after fitting a new cell
The U260 BIOS reads health data from an EEPROM register that carries over from the previous cell's charge history — not from the physical condition of the new cell. A fresh replacement will show a poor health flag until the learn cycle overwrites that register. Power the laptop on, let it run fully to hibernate on battery, then charge to 100% uninterrupted. After one complete cycle, recheck the battery status in Lenovo Energy Management or the BIOS; the health flag should clear and report a state-of-charge above 95%.