About this replacement
Fujitsu LifeBook A544 / E733 / E734 / AH564 — 10.8V Li-ion Replacement Battery (BPS229 / FPCBP405)
This is a 10.8V, 2000mAh (21.6Wh) Li-ion battery for the Fujitsu LifeBook A544, AH564, E733, and E734 series notebooks, along with 67 additional LifeBook models. It replaces OEM part numbers including BPS229, FMVNBP229A, FPCBP405, FPCBP416, FPCBP426, and related variants. If your original battery no longer holds a charge or the OS reports degraded health, this cell swaps directly into those slots.
- A544, E733, E734, and AH564 compatibility: These LifeBook models share a common 10.8V three-cell battery rail, the same physical connector pinout, and a unified BMS handshake protocol — which is why one SKU covers all of them. The BMS communicates charge state and health data over the SMBus line to the BIOS.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on LifeBook-class hardware. The BMS negotiated correctly with the firmware, accepted a full charge without triggering protection cutoff, and reported cell voltage within expected range on the SMBus.
- Post-swap learn cycle on LifeBook firmware: After installing this battery, discharge the laptop fully until it hibernates, then charge uninterrupted to 100% without interruption. This forces the BIOS battery learn cycle to recalibrate against the new cell and clears the false "poor health" or "unknown battery" warning that appears after every cell swap on this platform.
Why the LifeBook A544 BIOS flags a new battery as poor health
The LifeBook BIOS reads health data from the battery's EEPROM, which stores the original cell's rated capacity and cycle history. When you install a new cell, that EEPROM data does not match what the BIOS previously logged, so it flags the battery as degraded or unknown — even though the cell is fresh. This is not a fault with the replacement. Running one full discharge-to-hibernate cycle followed by an uninterrupted charge to 100% forces the BIOS learn cycle to write new baseline data and clear the warning.
LifeBook shutting down at 20–30% battery shown on screen
This happens when the fuel gauge IC still holds calibration data from the old, worn cell. The IC thinks 20% remaining is a safe cutoff point, but the actual voltage cliff on the new cell sits lower — so the laptop shuts down before the real reserve is used. The fix is a full calibration cycle: let the laptop discharge completely to hibernate cutoff, then charge to 100% without interruption. After two or three of these cycles, the fuel gauge IC recalibrates its discharge curve to the new cell and the shutdowns stop. Confirm the cell is reaching 12.6V at full charge before trusting the gauge readout.