AST A42 Notebook Replacement Battery 10.8V 6600mAh DR202

AST A42 / A51 / Ascentia A41 Series — 10.8V Li-ion Replacement Battery (DR202)

This is a 10.8V, 6600mAh (71.28Wh) Li-ion battery for AST notebook models including the A42, A51, A60 Plus, and Ascentia A41 series. It replaces OEM part numbers DR202, EMC36, ME202BB, NL2020, and SMP02. If your AST notebook no longer holds a charge or the existing cell has swollen, this is the direct cell swap.

• A42 / A51 / Ascentia A41 platform compatibility: These models share the same 10.8V three-cell series configuration, connector pinout, and BMS handshake protocol — which is why a single part number (DR202) covers the full range. Voltage rail and communication lines match across all listed models without modification.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on an AST A42 chassis. The BMS negotiated correctly with the system board, charge acceptance was normal from the first cycle, and protection circuits tripped at expected low-voltage cutoff thresholds.
• Post-install calibration for AST notebooks: After fitting this cell, run the laptop down to hibernate-cutoff under normal load, then charge uninterrupted to 100%. This forces the BIOS battery learn cycle to reset against the new cell's actual capacity and clears the inaccurate health warning that appears after every cell swap on this platform.

BIOS reporting poor battery health immediately after fitting the DR202

AST's BIOS reads health data stored in the battery's EEPROM and compares it against charge cycle history from the old cell. A brand-new cell has no cycle history, so the BIOS flags it as degraded or unknown on first boot. This is a data mismatch, not a fault with the replacement cell. Run one full discharge to hibernate-cutoff followed by an uninterrupted charge to 100% — the BIOS learn cycle rewrites its reference data against the new cell and the warning clears.

Laptop shuts down at 20–30% charge shown on the gauge

The fuel gauge IC calibrates itself against the old cell's voltage-to-capacity curve. After a swap, it still uses the previous curve, so it misreads the new cell's state of charge. When real cell voltage drops under full CPU and display load, the system hits actual low-voltage cutoff while the gauge still shows 20–30%. Two to three full discharge-and-charge cycles let the fuel gauge IC re-map the new cell's curve. After calibration, the gauge and actual cutoff will align — target a resting voltage of 10.8V at full charge as your confirmation point.