Clevo N240WU 14.8V Replacement Battery 6-87-N24JS-4UF

Clevo N240WU / N250WU — 14.8V Li-ion Replacement Battery (N240BAT-4)

This is a 14.8V, 2600mAh (38.48Wh) Li-ion battery for the Clevo N240WU, N250WU, Sager N240BU, and Sager N240JU notebooks. It replaces OEM part numbers N240BAT-3, N240BAT-4, and the 6-87-N24JS-4UF-1 series. When the original cell degrades and can no longer sustain voltage under load, this swap restores untethered operation.

• N240WU and N250WU platform fit: These models share the same battery bay dimensions, connector pinout, and BMS communication protocol — the same cell covers both. The 6-87-N24JS-42F and 42L suffix variants reflect minor BMS firmware revisions, not electrical differences, so one cell handles all affected units.
• Bench tested on actual hardware: We ran this cell on an N240WU and confirmed the BMS handshake completed without fault codes, the charge controller accepted a full charge cycle, and discharge current remained stable through a CPU-plus-display load test to the BMS low-voltage cutoff.
• Post-install calibration on the N240WU: After fitting, run the laptop on battery until it hibernates at low cutoff — do not interrupt — then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning that appears after every cell swap.

N240WU shutting down at 20–30% charge shown on screen

This happens when the cell voltage drops below the BMS cutoff threshold under full CPU and display load, even though the OS fuel gauge still shows charge remaining. The fuel gauge IC reads state-of-charge from a model it built around the old cell, so its percentage estimates are wrong for the new chemistry curve. Under a combined GPU-render and backlight load, the new cell's voltage cliff arrives earlier than the IC predicts. Run two full discharge-to-hibernate and charge-to-100% cycles — this forces the fuel gauge IC to recalibrate against the actual cell and corrects the early-shutdown behaviour.

BIOS showing incorrect Wh rating after battery replacement

The Wh figure the BIOS displays is read from the battery's EEPROM, which stores the rated capacity programmed at manufacture — not a live measured value. If the replacement cell carries a different EEPROM entry than the original, the BIOS will report a mismatched Wh figure in hardware info screens. This is an EEPROM data difference, not a fault with the cell or the laptop. The discrepancy does not affect charge behaviour; confirm actual capacity by checking the label on the cell itself, which will read 38.48Wh.