About this replacement
Samsung Ativ Book 9 Plus NP940X3G Series — 7.6V Li-Polymer Replacement Battery (AA-PLVN4AR)
This is a 7.6V, 7300mAh (55.48Wh) lithium-polymer replacement battery for the Samsung Ativ Book 9 Plus ultrabook. It fits the NP940X3G line, including NP940X3G-K01NL, NP940X3G-K01, and nine additional NP940X3G variants. It replaces OEM part AA-PLVN4AR directly.
- NP940X3G platform fit: All NP940X3G variants share the same 7.6V battery rail, connector pinout, and BMS handshake protocol. A single cell swap covers the full sub-series without adapter modifications or firmware changes.
- Bench tested on actual hardware: We cycled this cell on an NP940X3G unit and confirmed the BMS accepted the handshake on first connection, reported voltage correctly in Windows, and held charge curve within spec across three full cycles.
- Post-install calibration for NP940X3G: After fitting this cell, run one full discharge until the laptop hibernates at cutoff, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning that appears after every cell swap on this platform.
BIOS reporting poor battery health immediately after replacing the AA-PLVN4AR
Samsung's BIOS on the NP940X3G reads EEPROM data embedded in the original cell. When a new cell is installed, that EEPROM data is either absent or mismatched, so the BIOS flags health as poor or unknown — even if the new cell is at full capacity. This is a firmware recognition issue, not a hardware fault. Running one full discharge-to-hibernate followed by an uninterrupted charge to 100% forces a battery learn cycle and rewrites the health register. After two to three calibration cycles, the BIOS typically reports accurate health.
Ativ Book 9 Plus shutting down at 20–30% charge shown on screen
This happens when the fuel gauge IC loses calibration against the new cell's chemistry. The displayed percentage no longer matches actual cell voltage, so the laptop cuts power when the cell hits its low-voltage cliff — well before the gauge reaches 0%. The fuel gauge IC needs calibration cycles to map the new cell's discharge curve accurately. Run two full discharge-to-hibernate cycles, charging fully to 100% each time, and the gauge will converge to within 3–5% accuracy. Check that the cell voltage shown in battery diagnostics reaches at least 8.5V when fully charged.