About this replacement
Sony Clie PEG-N600C Series — 3.7V Li-Polymer Replacement Battery (UP503759-A4H)
This is a 3.7V 1100mAh lithium-polymer replacement battery for the Sony Clie PEG-N600C and compatible Clie models. It fits the PEG-N600C, PEG-N610, PEG-N610C, and PEG-N710, among others. Voltage and capacity match the OEM specification (UP503759-A4H) exactly.
- Clie N-series compatibility: These models share the same 3.7V battery rail, connector pinout, and physical cell dimensions (59.12 × 36.28 × 5.27mm). The BMS handshake across the N600C, N610, N610C, and N710 platforms accepts this cell without modification.
- Bench tested on actual hardware: We cycled this battery through charge and discharge on Clie hardware and confirmed the BMS reached full charge termination correctly, with no false low-voltage cutoffs during normal PDA operation.
- RAM data protection before swap: Sync all data to the host computer via HotSync before removing the battery. The Clie N-series stores contacts, calendar entries, and open application state in volatile RAM powered directly by the main cell — cutting power without syncing will wipe unsaved data.
Why the Clie PEG-N600C loses data after a battery replacement
The Clie PEG-N600C uses SRAM for working memory, and that SRAM is powered continuously by the main battery. The moment the cell drops below the retention threshold — or is physically removed — everything held in RAM is gone. This is not a fault with the replacement battery; it is how Palm OS-era PDAs managed memory. Before swapping the cell, run a full HotSync to write all data to the desktop. After fitting the new battery, a cold boot will restore the OS from flash, and a second HotSync will push your data back.
Clie PEG-N600C not booting after new battery fitted
A freshly shipped lithium-polymer cell may arrive at a storage charge level — typically around 3.6V — which can fall below the Clie's minimum boot voltage threshold. If the screen stays blank or shows only a low-battery icon, do not assume the battery is faulty. Connect the original Sony AC adapter and allow the device to charge for at least 30 minutes before attempting to power on. If the unit still will not boot after reaching approximately 3.7V, perform a hard reset by holding the reset pin while pressing the power button.