About this replacement
Asus Chromebook C204MA / Flip C214MA — 11.55V Li-Polymer Replacement Battery (C31N1836)
This 11.55V, 3500mAh (40.43Wh) Li-Polymer cell replaces the original battery in the Asus Chromebook C204MA and Flip C214MA series. It fits the C204MA-GJ0003, C204MA-BU1430, C204MA-YS02-GR, and the ruggedised Flip C214MA among others. OEM part numbers C31N1836, C31N1836-1, 0B200-03370000, and 0B200-03370100 all match this cell.
- C204MA and C214MA platform fitment: Both the standard C204MA and the Flip C214MA share the same 11.55V three-cell architecture, connector pinout, and BMS handshake protocol — which is why one cell covers the full lineup. The voltage rail feeds the MediaTek SoC directly, so a mismatch here causes immediate POST failure, not just reduced capacity.
- Bench tested on actual hardware: We cycled this cell on a C204MA chassis and confirmed the BMS accepted the new EEPROM data without throwing a health fault on first boot. Charge termination landed at the correct 12.6V ceiling. Discharge cutoff triggered cleanly at the expected low-voltage threshold before the system could force a hard shutdown.
- Post-swap calibration on ChromeOS: After fitting this cell, run one full discharge down to hibernate cutoff, then charge uninterrupted to 100% without unplugging mid-cycle. This forces the fuel gauge IC to re-map against the new cell's actual capacity curve and clears the inaccurate health warning ChromeOS flags after every cell swap.
Why ChromeOS flags "battery health poor" immediately after replacing the C204MA cell
The C204MA's embedded controller reads health data from the battery's EEPROM — not from live voltage measurements. When a new cell arrives, that EEPROM may carry factory default values that don't match the embedded controller's expected charge history, triggering an instant poor-health flag. This is a data mismatch, not a faulty battery. Running a full discharge-to-hibernate followed by a clean charge to 100% lets the embedded controller overwrite the stale EEPROM reference with a fresh baseline. After one to two full cycles the health indicator should clear and read accurately.
Chromebook C204MA shutting down suddenly at 20–30% shown on the gauge
This happens when the cell voltage drops below the BMS cutoff threshold while the OS fuel gauge still reads 20–30% — a calibration gap, not a hardware fault. Under full load — display at max brightness, active tabs, and the MediaTek SoC at peak clock — voltage sags faster than the uncalibrated gauge anticipates. The cell hits the hard cutoff at roughly 9.9V and the system drops instantly. Fix this by completing two full discharge-to-hibernate and uninterrupted charge cycles so the fuel gauge IC can re-anchor its low-voltage estimate to the new cell's actual discharge curve.