Acer AcerNote A Series DR36 Replacement Battery 12V 3800mAh

Acer AcerNote A Series — 12V Ni-MH Replacement Battery (DR36)

This is a 12V, 3800mAh (45.6Wh) Ni-MH replacement battery for the Acer AcerNote A Series notebook computers. It fits models that take the DR36 or DR36S battery pack. It restores off-AC operation to these vintage Acer portables when the original cell has degraded past useful capacity.

• AcerNote A Series fit: All models in this line share the same 12V power rail, physical form factor, and connector pinout — that's why a single part number covers the entire series without modification.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge on AcerNote A Series hardware. The BMS accepted the pack without fault codes, and the charge circuit completed normally through all stages.
• First-install cycle reset: After fitting this battery, run a full discharge down to hibernate cutoff, then charge uninterrupted to 100%. Ni-MH cells in this platform require that full learn cycle for the BIOS to recalibrate its capacity reference — skipping it leaves an inaccurate health warning on screen after every swap.

Why the AcerNote A Series shuts down at 20–30% charge shown

This is a voltage cliff issue, not a BIOS bug. Under combined CPU and display load, the Ni-MH cell voltage drops faster than the fuel gauge IC can track against its stored reference data. The system hits the low-voltage cutoff threshold while the gauge still reads 20–30%. Running one full calibration cycle — discharge to hibernate cutoff, then a clean uninterrupted charge — aligns the gauge IC reference to the actual cell chemistry and clears the premature shutdown.

BIOS reporting battery health as poor or unknown after fitting a new cell

The BIOS reads health data from EEPROM registers that were written by the original cell over its lifetime. A new cell arrives with fresh EEPROM values that don't match the degraded baseline the BIOS expects, so it flags the pack as unknown or poor. This is not a fault with the replacement battery. Run the battery learn cycle — one full discharge to hibernate cutoff followed by a full charge — and the BIOS will rewrite its reference against the new cell. Health reporting normalises after one to two complete cycles.