About this replacement
Acer Aspire V5-171 / One 725 / One 756 — 11.1V Li-ion Replacement Battery (AL12B32)
This is an 11.1V, 4400mAh (48.84Wh) Li-ion battery for the Acer Aspire V5-171, Aspire One 725, Aspire One 756, and Chromebook AC710. It replaces OEM part numbers AL12B32, AL12B72, KT.00407.002, KT.00403.004, AL12B31, and AL12X32. If your original cell no longer holds a charge or the laptop shuts off unexpectedly, this is a direct swap.
- Aspire V5-171 and One 7xx series compatibility: These models share the same 11.1V three-cell rail, identical connector pinout, and matching BMS communication protocol — which is why a single part number covers all of them. The BMS on each platform expects the same voltage thresholds and cell-count handshake.
- Bench tested on actual hardware: We cycled this cell on an Aspire V5-171 chassis. The BMS accepted the new cell without fault codes, charge current ramped correctly through CC and CV phases, and the protection circuit tripped cleanly at the expected low-voltage cutoff during discharge.
- Post-install calibration on the V5-171: After fitting this battery, run one full discharge down to hibernate cutoff, then charge uninterrupted to 100%. This resets the BIOS battery learn cycle and clears the inaccurate health warning that appears on the first boot after any cell swap.
Why the Aspire V5-171 BIOS reports "poor battery health" after a new cell is fitted
The V5-171 BIOS reads health data from the battery's EEPROM, which stores charge-cycle count and rated capacity from the previous cell. When a new cell goes in, the EEPROM data doesn't automatically reset — the BIOS compares the new cell's actual charge against the old cell's stored history and flags a mismatch as poor health. This is a firmware interpretation issue, not a fault with the replacement cell. Running one full discharge-to-hibernate then an uninterrupted charge to 100% forces the BIOS to re-write the battery learn table against the new cell. After two to three cycles, the health indicator typically resolves to normal.
Aspire V5-171 shutting down at 20–30% charge shown on screen
This happens when the fuel gauge IC hasn't yet calibrated against the new cell's actual voltage curve. The IC is still using the discharge profile from the old, degraded cell — so it triggers a low-battery shutdown well before the new cell is actually depleted. The fix is the same calibration cycle: drain the battery fully to hibernate cutoff, then charge to 100% without interruption. After two full cycles, the fuel gauge re-maps the voltage-to-percentage curve and the early shutdowns stop. If it persists past three cycles, check that the BIOS is not running a capped charge-limit profile — navigate to BIOS power settings and confirm the charge ceiling is set to 100%.