About this replacement
Pocketbook Pro 602 / 902 Series — 3.7V Li-ion Replacement Battery (1ICP4/40/60 1S1P)
This is a 3.7V, 1100mAh Li-ion cell that fits the Pocketbook Pro 602, Pro 603, Pro 902, and Pro 903 e-readers. It replaces the original 1ICP4/40/60 1S1P cell that powers the e-ink display, page-turn controller, and USB charging circuit. Swap it in when the device no longer holds a charge or fails to power on at all.
- Pro 602 / 603 / 902 / 903 compatibility: These four models share the same battery bay dimensions (65.80 × 53.70 × 4.80mm), connector pinout, and BMS handshake protocol — all four accept this cell without modification.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the Pro 602 platform. The BMS accepted the cell, the protection circuit tripped correctly at the low-voltage threshold, and the firmware read state-of-charge without error flags.
- Post-swap USB charge requirement: Pocketbook firmware recalibrates its fuel gauge after a cell swap. Plug into USB immediately after installation and run a full charge before first use — skipping this step causes the percentage indicator to jump erratically for several cycles.
Why the Pro 602 shows low battery immediately after a new cell is installed
Replacement cells ship at storage voltage — typically 3.6–3.7V — not at full charge. The Pocketbook firmware interprets anything below its calibrated full-charge threshold as a low battery state and displays the warning icon straight away. This is a firmware reporting issue, not a cell defect. Connect the device to a USB charger and let it complete a full charge cycle before drawing any conclusions about the new cell's condition.
Page turns sluggish or delayed after replacing the battery
E-ink displays require a voltage pulse to refresh each pixel. When the cell voltage sags — even briefly — the controller extends the refresh window to compensate, which appears as a slow or stuttering page turn. This typically occurs when the new cell hasn't completed its first full charge and is operating at the lower end of its voltage range. Charge fully to 4.2V and the response time returns to normal. If sluggishness continues after a full charge, check that the connector is fully seated and making clean contact.