Mitac Mio 558 Replacement Battery LIP1298MIPT 3.7V 1300mAh

Mitac Mio 558 / Mio P4QMIO558 — 3.7V Li-Polymer Replacement Battery (LIP1298MIPT)

This is a 3.7V, 1300mAh Li-Polymer replacement battery for the Mitac Mio 558 and Mio P4QMIO558 portable GPS and PDA devices. It matches the original LIP1298MIPT cell, restoring power to mid-2000s Mio units used for navigation, route planning, and personal information management. Slot it into the original battery bay — no modifications needed.

• Mio 558 and P4QMIO558 fit: Both models share the same battery bay dimensions, voltage rail, and connector pinout. The LIP1298MIPT cell works across the pair without any adapter or wiring change.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a Mio 558 unit. The BMS held the 3.7V nominal rail steady across GPS lock, backlight, and active map rendering — no voltage collapse under simultaneous load.
• RAM data sync before swap: The Mio 558 holds open files, contacts, and application state in volatile SRAM powered directly by the main battery. Sync the device to ActiveSync or a host PC before pulling the old cell — any unsaved data in RAM is lost the moment the battery disconnects.

Why the Mio 558 drops GPS signal faster as the battery ages

The Mio 558 runs its GPS receiver and backlight simultaneously, which draws more current than standby alone. As the Li-Polymer cell ages, internal resistance rises — the voltage sags under this combined load even when the charge indicator still reads mid-level. The GPS module is voltage-sensitive and can drop lock before the battery meter hits empty. Replacing the cell restores the full 3.7V rail and stable GPS reception under load.

Mio 558 stuck on boot screen after new battery install

A freshly shipped Li-Polymer cell often arrives at a storage charge of around 3.0–3.2V — below the minimum the Mio 558 boot sequence needs to initialise the OS and flash storage. The device starts to power on, then stalls or loops on the boot screen. Connect the unit to its charger for at least 30 minutes before attempting to boot. Once the cell reaches approximately 3.5V, the boot sequence completes normally.