About this replacement
Asus BR1100CKA / Expertbook B1 B1400CEAE — 11.55V Li-Polymer Replacement Battery (0B200-03760000)
This is an 11.55V, 3500mAh (40.43Wh) Li-Polymer battery for Asus laptops including the BR1100CKA, BR1100FKA, Expertbook B1 B1400CEAE, and the 5895 series. It replaces OEM part numbers 0B200-03760000, B31N1915, C31N1915, and C31N2015. Physical dimensions are 281.75 × 74.10 × 5.60mm — verify your bay dimensions before ordering.
- BR1100 and B1400 series compatibility: These models share a three-cell Li-Polymer configuration on the same 11.55V rail with a common connector pinout and BMS handshake protocol. The same OEM part number spans all listed variants — Asus used a single battery platform across this generation.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a BR1100CKA unit. The BMS negotiated correctly, charge current ramped to the expected CC/CV profile, and cutoff triggered cleanly at the top of charge with no fault codes thrown.
- Post-install calibration cycle: After fitting this battery, run the laptop down to the hibernate-cutoff point, then charge uninterrupted to 100% without use. This forces the BIOS to complete a 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
Asus BIOS reads health data from EEPROM registers carried over from the previous cell — not from live measurements of the new one. After a swap, the firmware sees mismatched cycle count and capacity data and flags the battery as degraded. This is a firmware artefact, not a defect in the replacement cell. One complete discharge-to-hibernate followed by a full uninterrupted charge resets the learn cycle and updates the EEPROM baseline to match the new cell's actual capacity.
Laptop shuts down abruptly at 20–30% charge shown on screen
This happens when the fuel gauge IC has not yet calibrated against the new cell's voltage curve. The OS reads a state-of-charge estimate built on the old cell's profile, so the reported percentage diverges from actual cell voltage. Under full CPU and display load, the cell hits its minimum discharge voltage while the gauge still shows 20–30% remaining — the laptop cuts out to protect the cell. Run two to three full discharge-and-recharge cycles and the fuel gauge IC will re-anchor its model to the new cell, after which the shutdowns stop.