About this replacement
Dynabook Portege X30W-K Series — 15.4V Li-Polymer Replacement Battery (PS0010UA1BRS)
This 15.4V, 3400mAh (52.36Wh) Li-Polymer cell replaces the original battery in the Dynabook Portege X30W-K-101 and over 90 related X30W-K variants. It restores full-cycle charging to this ultraportable convertible notebook. Voltage, connector, and BMS signalling match the OEM spec PS0010UA1BRS.
- X30W-K platform fit: All Portege X30W-K variants share the same 15.4V voltage rail, slim Li-Polymer form factor, and four-pin BMS connector. That common architecture is why one cell covers the full range from the -101 through to the -13H and beyond.
- Bench tested on actual hardware: We ran this cell through charge, discharge, and wake-from-sleep cycles on an X30W-K unit. The BMS handshake completed without fault codes, and the charge controller accepted the full 52.36Wh capacity without interruption.
- Post-swap calibration on the X30W-K: After installing, run one full discharge to hibernate-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 fitting a new cell
The X30W-K BIOS stores charge history and health data in EEPROM on the original cell. When a new cell goes in, that EEPROM data is gone — the BIOS has no reference point and flags health as poor or unknown by default. This is not a fault with the replacement cell. Run a full discharge-to-hibernate then a full uninterrupted charge to 100% and the BIOS learn cycle will overwrite the stale data. After one complete cycle the health status should clear to normal.
Laptop shutting down at 20–30% charge shown on screen
This happens when the fuel gauge IC is still calibrated against the old, degraded cell and has not yet mapped the voltage curve of the new one. The displayed percentage does not match actual cell voltage — the laptop hits the hardware low-voltage cutoff while the OS still shows capacity remaining. The fix is two to three full discharge-to-hibernate and full-recharge cycles, which let the fuel gauge IC relearn the voltage-to-capacity curve. After calibration, shutdown should not occur above approximately 10.8V under load.