Asus ZenBook Pro Duo UX581GV Compatible Battery 15.4V 3900mAh

Asus ZenBook Pro Duo UX581GV Series — 15.4V Li-Polymer Replacement Battery (C42N1846)

This is a 15.4V, 3900mAh (60.06Wh) Li-Polymer replacement battery for the Asus ZenBook Pro Duo UX581GV series. It fits the dual-screen ZenBook Pro Duo notebook, which runs both a primary display and a secondary ScreenPad Plus from the same power rail. OEM part numbers are C42N1846 and 0B200-03490000.

• UX581GV model coverage: The H2004T, H2001T, H2037T, H2002R and over 30 additional UX581GV variants all share the same 15.4V four-cell Li-Polymer pack, BMS connector pinout, and charge controller handshake — one cell fits the full range.
• Bench tested on actual hardware: We cycled this cell on a UX581GV unit under simultaneous main-display and ScreenPad Plus load. The BMS held charge cutoff correctly at the expected voltage ceiling and passed temperature threshold checks at sustained GPU draw.
• Post-install calibration on the ZenBook Pro Duo: After fitting, run the laptop down to hibernate cutoff on battery only — both screens active accelerates the draw — then charge uninterrupted to 100%. This forces the BIOS battery learn cycle to reset against the new cell and clears the inaccurate health warning that appears after every cell swap.

Why BIOS reports poor battery health immediately after fitting a new cell

The ZenBook Pro Duo stores charge history and health data in the battery EEPROM. When you swap cells, the BIOS reads stale data from the old EEPROM and flags the pack as degraded before it has run a single cycle. This is a firmware read, not a fault with the replacement cell. One full discharge-to-hibernate followed by a complete uninterrupted charge resets the learn cycle and updates the health register. After two to three full cycles, BIOS and Windows battery reporting will reflect the actual cell condition.

ZenBook Pro Duo shutting down at 20–30% battery shown on screen

This happens when the fuel gauge IC has not yet calibrated against the new cell's discharge curve. The IC inherited the old cell's voltage-to-capacity mapping, so it misreads remaining charge — the cell hits its voltage floor while the OS still shows 20–30% remaining. It is not a fault with the replacement pack. Run two to three full discharge and charge cycles with both screens active to give the fuel gauge IC real data points against the new cell. After calibration, the shutdown will align with 0–5% as shown, and the gauge will hold accuracy under the dual-display load this machine draws.