Fujitsu Loox 610 A716/MBT Replacement Battery 3.7V 1500mAh

Fujitsu Loox 610 Series — 3.7V Li-ion Replacement Battery (A716/MBT)

This is a 3.7V, 1500mAh Li-ion cell replacing OEM part A716/MBT in the Fujitsu Loox 610, 610BT, and 610BT/WLAN Pocket PCs. These mid-2000s Windows Mobile handhelds run scheduling, contact management, and data access tasks where a dead or degraded battery ends every session abruptly. Voltage and physical form factor match the original spec.

• Loox 610, 610BT, and 610BT/WLAN compatibility: All three models share the same battery bay dimensions, connector pinout, and 3.7V voltage rail. The BMS handshake between the device and the cell is identical across the trio, so a single replacement part covers all three variants without modification.
• Bench tested on actual hardware: We cycled this cell through full charge and discharge on the Loox 610 platform. The BMS accepted the cell without error flags, the device reported correct charge state, and the voltage held stable across active Wi-Fi and Bluetooth radio use.
• RAM data sync before removal: The Loox 610 stores open files, application state, and unsaved data in volatile SRAM powered directly by the main battery. Before removing the old cell, sync the device fully to a host PC via ActiveSync and confirm all data has transferred — pulling the battery without syncing will wipe whatever is held in RAM.

Why the Loox 610 loses all data when the battery runs flat

The Loox 610 uses SRAM as its primary working memory. Unlike flash storage, SRAM requires continuous power to retain its contents. When the main battery drops below the device's minimum operating voltage — or is physically removed — every open file, contact record, and application session stored in RAM is gone instantly. There is no automatic save-to-flash on shutdown. Always sync to a host PC before the battery reaches critical levels, not after.

Loox 610 stuck on boot screen after fitting a new battery

A fresh replacement cell ships at partial state of charge, often around 30–40% capacity. The Loox 610 boot sequence pulls a short high-current spike that can trip the BMS if the cell voltage is too low at the start. If the device stalls on the boot screen or restarts in a loop, connect it to a charger before attempting to power it on. Allow the cell to reach at least 3.9V before booting — check this by letting the charge indicator run for 20–30 minutes first.