About this replacement
Asus Chromebook C403NA Series — 7.7V Li-Polymer Replacement Battery (C22N1626)
This is a 7.7V, 5900mAh (45.43Wh) Li-Polymer replacement battery for the Asus Chromebook C403NA and Flip C213NA series. It fits the C403NA-FQ0004, C403NA-FQ0005, C213NA-BW0034, and over 24 additional Chromebook variants sharing the C22N1626 platform. The OEM part numbers C22N1626, 0B200-02440100, 0B200-03320000, and C22N1626-1 all cross-reference to this cell.
- C403NA and C213NA platform fit: Both the standard C403NA and the ruggedised Flip C213NA share the same 7.7V cell voltage, two-cell Li-Polymer configuration, and BMS handshake protocol — which is why they run the same OEM part number across that 24-model spread.
- Bench tested on actual hardware: We ran this cell on a C403NA chassis and confirmed the BMS handshake completed cleanly, charge current ramped normally through CC/CV phases, and the fuel gauge IC registered capacity without throwing a fault code.
- First-cycle learn procedure after install: After fitting, let the Chromebook discharge fully until Chrome OS forces a shutdown, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning that nearly always appears after a cell swap on this platform.
Why Chrome OS reports battery health as "poor" immediately after fitting a new cell
The EC (embedded controller) on the C403NA stores charge history and capacity data from the previous cell in non-volatile memory. When a new cell is installed, that stored data no longer matches the actual cell state, so the EC flags a health warning based on stale figures. Running one full discharge-to-shutdown followed by an uninterrupted charge to 100% forces the EC to rewrite its capacity baseline against the new cell. After two to three cycles the reported health figure will stabilise at its correct value.
Chromebook shutting down at 20–30% charge shown on screen
This is a voltage-cliff issue, not a capacity issue. Under combined CPU and display load the cell voltage drops faster than the fuel gauge IC can track — when voltage hits the EC's cutoff threshold, the system shuts down even though the percentage shown still looks usable. It typically appears in the first few cycles before the fuel gauge IC has calibrated against the new cell's actual discharge curve. Run two full discharge-to-hibernate cycles with the screen at full brightness and a CPU-active task running to force calibration. After calibration, the shutdown threshold and the displayed percentage will align, with cutoff occurring close to 5–8% remaining.