About this replacement
Samsung Chromebook 15.6" XE350XBA-K01US — 7.7V Li-Polymer Replacement Battery (BA43-00390A)
This is a 7.7V, 5000mAh (38.5Wh) lithium-polymer replacement battery for the Samsung Chromebook 15.6", including the XE350XBA-K01US. It slots into the original battery bay and connects through the existing harness. Install it when the factory cell no longer powers the board or fails to hold a charge.
- XE350XBA platform fit: The XE350XBA series runs a single 7.7V battery rail with a five-pin SMBus connector. This cell matches that rail voltage and connector pinout exactly. The BMS handshake completes on first boot — no firmware patch required.
- Bench tested on actual hardware: We cycled this cell on the XE350XBA board and confirmed the BMS accepted the new chemistry, released the charge circuit, and allowed a full charge to 100%. Cutoff voltage at the low end held at 6.0V before the board triggered safe shutdown.
- First-cycle calibration on the Chromebook: After installing, run one full discharge until the device hibernates at low-battery cutoff, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle. Skipping this step leaves the fuel gauge reading inaccurate and can trigger a false "battery low health" warning in Chrome OS settings.
Chrome OS flagging BA43-00390A as poor health immediately after installation
Chrome OS reads battery health from EEPROM data stored on the SMBus controller — not from live cell voltage. When a new cell goes in, the controller still holds cycle count and degradation figures from the old pack. The OS reports those stale figures as the current battery state. Running the full discharge-to-hibernate then uninterrupted charge-to-100% sequence forces the fuel gauge IC to rewrite its baseline against the new cell. After one or two full cycles, the health percentage in chrome://system normalises.
Chromebook shutting down at 20–30% charge shown on screen
This is a voltage cliff failure, not a capacity fault. Under full CPU and display load, the cell voltage drops faster than the fuel gauge IC can track — the board sees terminal voltage fall below the safe threshold and cuts power before the display counter reaches zero. The fuel gauge IC has not yet mapped the new cell's discharge curve to its internal model. Run two to three complete discharge-to-hibernate and full-recharge cycles. After calibration, the shutdown point and the displayed percentage will align — confirm by checking that battery voltage stays above 7.0V at the 15% mark under load.