Rollei Prego 8330 Replacement Battery 3.7V 1250mAh

Rollei Prego 8330 — 3.7V Li-ion Replacement Battery (02491-0028-01)

This 3.7V, 1250mAh Li-ion cell replaces the original battery in the Rollei Prego 8330 and Prego DP8330 compact digital cameras. It also fits the Prego DP8300 and RCP-7430XW. Capacity matches the OEM spec at 4.63Wh — no modification needed to fit the battery compartment.

• Prego 8330 and DP-series fit: These models share the same battery bay dimensions, 3.7V voltage rail, and connector orientation. The same OEM part numbers — 02491-0028-01 and 02491-0028-00 — cross all listed models, confirming cell compatibility across the range.
• Bench tested on actual hardware: We cycled this cell through the Prego 8330 body and monitored BMS handshake, charge acceptance, and voltage stability under flash-capacitor recharge loads. The BMS accepted the cell without error flags across multiple charge cycles.
• First charge cycle on the Prego 8330: Charge this cell fully inside the camera body or OEM charger before your first shoot. The Prego's BMS maps battery-remaining display against the new cell's discharge curve during that initial cycle — skipping it can cause the indicator to read inaccurately for the first several uses.

Flash capacitor recharge current and what it does to a new cell's voltage

Every time the Prego 8330 recycles its flash, the capacitor draws a sharp burst of current from the battery. On a fresh cell, this causes a brief voltage dip that the BMS logs. If that dip crosses the low-voltage threshold — typically under 3.0V momentarily — the camera may flag a low-battery warning even with significant charge remaining. This is normal behaviour on the first few charge cycles as the cell conditions. After two or three full cycles, the internal resistance settles and the dip becomes less pronounced.

Battery percentage jumping erratically on the Prego display

The Prego 8330 maps its battery indicator to fixed voltage thresholds calibrated for the OEM cell's discharge curve. A new replacement cell may discharge along a slightly different curve, causing the indicator to jump — for example, from 60% to 20% without warning. This is a display mapping issue, not a cell fault. Run two full charge-discharge cycles inside the camera body to allow the BMS to recalibrate its threshold readings. After that, the indicator should track steadily down from 4.2V at full charge.