Lenovo IdeaPad 3-15 Replacement Battery L19D3PF5 11.1V

Lenovo IdeaPad 3-15 — 11.1V Li-Polymer Replacement Battery (L19D3PF5)

This 11.1V, 3950mAh (43.85Wh) Li-Polymer battery replaces the original cell in the Lenovo IdeaPad 3-15 and the IdeaPad 3-14 series, including models 81WA005WAU and 81WA005UAU. It covers OEM part numbers L19D3PF5, L19C3PF7, L19L3PF5, 5B10X02599, 5B10X02602, SB10X02596, SB10X02598, and SB10X02601. Check your original battery label or the BIOS hardware info page to confirm your part number before ordering.

• IdeaPad 3-14 and 3-15 platform compatibility: These models share the same 11.1V battery rail, connector pinout, and BMS communication protocol across the IML05 and IIL05 board revisions — which is why a single cell covers all of them. Voltage tolerance on this platform is tight; any cell outside spec trips the BIOS charge controller immediately.
• Bench tested on actual hardware: We ran this cell on an IdeaPad 3-15 board and monitored the BMS handshake at insertion. The charge controller accepted the cell, the BMS protection circuit engaged correctly at both low-voltage cutoff and full-charge termination, and the fuel gauge IC began tracking state-of-charge within one partial cycle.
• Post-install calibration on IdeaPad 3 series: After fitting this battery, run one full discharge down to the BIOS hibernate cutoff, then charge uninterrupted to 100% without using the laptop. This resets the BIOS battery learn cycle and clears the inaccurate health warning that shows after every cell swap on this platform.

BIOS reporting battery health as poor immediately after replacement

The IdeaPad 3 BIOS reads health data from the cell's EEPROM register, which stores the original factory capacity of the old cell. When a new cell is installed, that register hasn't been rewritten yet, so the BIOS compares current state-of-charge against stale reference data and flags the battery as degraded. This is not a fault with the new cell. Run one full discharge-to-hibernate cycle followed by an uninterrupted charge to 100% — this forces the BIOS learn cycle to rewrite the reference data against the new cell's actual capacity. After one or two full cycles, the health indicator should return to normal.

Laptop shutting down at 20–30% charge shown on screen

This happens when the cell voltage drops faster than the fuel gauge IC expects under combined CPU and display load. The gauge still shows 20–30% remaining, but the actual cell voltage has already hit the BMS low-voltage cutoff threshold — around 9.0V for this 3S Li-Polymer pack — and the BMS shuts the system down to protect the cells. It's most common in the first few cycles on a new cell, before the fuel gauge IC has calibrated its discharge curve against the new chemistry. Run two or three full discharge-to-hibernate cycles to let the IC build an accurate voltage-versus-capacity map, and the early shutdowns will stop.