Clevo W830T Replacement Battery 11.1V 5500mAh

Clevo W830T / W840T — 11.1V Li-Polymer Replacement Battery (W830BAT-3)

This is an 11.1V, 5500mAh (61.05Wh) Li-Polymer battery for the Clevo W830T and W840T notebooks. It replaces OEM part numbers W830BAT-3 and 6-87-W84TS-427. Both models use the same cell configuration, voltage rail, and connector pinout, so one SKU covers the pair.

• W830T and W840T compatibility: Both notebooks share the same battery bay dimensions, 11.1V three-cell architecture, and BMS communication protocol. The connector locks and the BMS handshake completes without modification on either platform.
• Bench tested on actual hardware: We ran charge and discharge cycles on this cell against the W830T board. The BMS accepted the cell, reported state-of-charge correctly after two calibration cycles, and thermal cutoff triggered only above the expected threshold under sustained CPU load.
• Post-install calibration on the W830T: After fitting this cell, 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 on the first boot after any cell swap.

BIOS reporting battery health as poor after replacement on the W830T

The W830T BIOS reads health data from EEPROM registers that the old cell wrote during its lifetime. A new cell arrives with fresh EEPROM values that don't match the accumulated cycle history the firmware expects. The BIOS interprets this mismatch as a degraded or unknown battery and flags poor health immediately. Running one full discharge-to-hibernate then a complete uninterrupted charge lets the firmware overwrite those registers with data from the new cell and clears the warning.

W830T shutting down at 20–30% charge shown on screen

This happens when the fuel gauge IC still holds calibration data from the old, degraded cell. Under full CPU and display load, the new cell's actual voltage at that state-of-charge is higher than the old cell's was — but the firmware's discharge curve hasn't updated yet, so it triggers shutdown prematurely. The fix is two to three complete discharge and charge cycles so the fuel gauge IC maps its cutoff thresholds to the new cell's actual voltage curve. After calibration, shutdown should not occur until the cell reaches approximately 10.5V under load.