About this replacement
Lenovo Yoga Chromebook C630 — 7.5V Li-Polymer Replacement Battery (L18M4PG0)
This 7.5V, 7350mAh (55.13Wh) lithium-polymer battery replaces the original cell in the Lenovo Yoga Chromebook C630 and Chromebook C340-15. It matches OEM part numbers including L18C4PG0, L18D4PG0, L18L4PG0, L18M4PG0, and SB10W67333. The physical dimensions — 253.10 x 115.40 x 5.40mm — match the slim cell bay shared across both models.
- C630 and C340-15 shared platform: Both models run the same 7.5V battery rail, use the same connector pinout, and share BMS handshake logic. That is why one cell covers both devices without modification.
- Bench tested on actual hardware: We cycled this cell through charge, discharge, and reinsertion on a C630 unit. The BMS accepted the new cell, reported voltage correctly, and did not trigger a protection fault on reconnection.
- Post-install calibration cycle: After fitting this battery, run one full discharge to the hibernate cutoff point, then charge uninterrupted to 100%. This forces the fuel gauge IC to re-learn the new cell's capacity curve and clears the inaccurate health warning that ChromeOS logs after every cell swap.
Why ChromeOS reports battery health as poor immediately after replacement
The EC firmware on the C630 stores charge cycle count and health data in EEPROM tied to the old cell. When a new cell is installed, that stored data does not reset automatically — ChromeOS reads stale values and flags the battery as degraded. The fix is a learn cycle: discharge fully to hibernate, then charge to 100% without interruption. After one or two full cycles, the fuel gauge IC re-calibrates against the actual cell capacity and the health warning clears.
C630 shutting down at 20–30% charge shown on screen
This happens when the fuel gauge IC is still calibrated to the old, degraded cell — it underestimates how much voltage the new cell drops under combined CPU and display load. When the system pulls peak current, the cell voltage dips below the EC's cutoff threshold before the on-screen percentage reaches zero. Run the full discharge-to-hibernate cycle described above. After calibration, the percentage readout aligns with actual cell voltage and the early shutdown stops.