BAT-310 Acer Allegro Replacement Battery 3.7V 1300mAh

Acer Allegro / M310 / W4 — 3.7V Li-ion Replacement Battery (BAT-310)

This is a 3.7V, 1300mAh Li-ion cell for the Acer Allegro, M310, and W4 pocket PC and PDA devices. It slots in where the original BAT-310 (also listed as BT-0010S.002 and BT300107-011) was fitted at the factory. Capacity is 1300mAh / 4.81Wh — matching the original specification.

• Allegro / M310 / W4 platform fit: All three models share the same battery bay dimensions (65.50 × 42.00 × 4.50mm), the same single-cell 3.7V architecture, and the same connector pinout — which is why one cell covers all three variants.
• Bench tested on actual hardware: We cycled this cell through the Allegro's charge controller and confirmed the BMS accepted charge without fault flags. Cell voltage at full charge held at the expected 4.2V cutoff with no thermal events during discharge.
• Sync before you swap: The Allegro holds open files and application state in RAM powered directly by the main battery. Removing the cell without first syncing to a host PC or performing a full ActiveSync backup will erase unsaved data permanently — not just suspend it.

Why the Allegro loses data every time the battery is removed

The Allegro uses SRAM for active storage — it holds the operating state, open files, and installed application data in volatile memory backed entirely by the main battery. There is no secondary coin cell or supercapacitor to bridge a swap. The moment the battery voltage drops below approximately 3.0V or the cell is physically removed, that RAM loses power and its contents are gone. A complete ActiveSync or Windows Mobile Device Center sync to the host PC before removal is the only way to prevent data loss.

Allegro not booting after new battery fitted

A freshly shipped Li-ion cell may arrive at a storage charge of around 3.6–3.7V — below the minimum threshold the Allegro's boot sequence requires to initialise the radio, display, and storage controller simultaneously. If the device shows nothing or hangs on the Acer splash screen, place it on charge for at least 90 minutes before attempting a cold boot. Once the cell reaches 4.0V or above, the boot sequence completes normally. Do not repeatedly press the power button while voltage is low — this can trigger a BMS lockout requiring a full charge cycle to clear.