About this replacement
Sony PRS-700 / PRS-700BC — 3.7V Li-Polymer Replacement Battery (A98839601 294)
This 3.7V, 800mAh lithium-polymer cell replaces the original battery in the Sony PRS-700 and PRS-700BC e-readers. It matches the OEM part number A98839601 294 and fits the same 63.00 × 36.00 × 4.00mm footprint as the factory cell. If your Reader powers off unexpectedly or won't hold a charge through a reading session, this is the direct replacement cell.
- PRS-700 and PRS-700BC compatibility: Both models use the same internal battery bay, connector pinout, and BMS handshake protocol. A single cell covers both variants — no adapter or modification needed.
- Bench tested on actual hardware: We ran this cell on a PRS-700 unit and confirmed the BMS accepted the new cell without error flags, reported voltage correctly through the firmware, and held charge across multiple charge cycles.
- First-charge calibration on e-reader firmware: After swapping the cell, charge via USB until the indicator shows 100% before switching the device on. Sony Reader firmware recalibrates its battery percentage display against a full-charge baseline — skipping this step causes the percentage counter to jump or read inaccurately from the start.
Why the PRS-700 shows low battery immediately after a new cell is installed
Replacement cells ship at storage voltage — typically around 3.6V to 3.85V — not at full charge. The PRS-700 firmware reads this as a partially depleted battery and flags it immediately. The cell itself is not faulty. Connect the device to USB and charge it to 4.2V (full) before powering on. Once the firmware completes a full charge cycle, the percentage display tracks the new cell correctly.
PRS-700 not powering on at all after battery replacement
If the cell voltage has dropped below approximately 3.0V during storage or shipping, the PRS-700's BMS will block startup to protect the system — the device appears completely dead. Connect it to a USB charger and leave it for at least 10 minutes without pressing the power button. The BMS needs to detect a minimum threshold voltage before it permits a boot sequence. Once charging begins and the LED activates, the device will power on normally.