Polaroid T831 3.7V Replacement Battery 02491-0066-00 660mAh

Polaroid T831 Series — 3.7V Li-ion Replacement Battery (02491-0066-00)

This 3.7V Li-ion cell at 660mAh (2.44Wh) replaces the original battery in the Polaroid T831, T833, T730, and CTA-00730S compact digital cameras. It matches the OEM form factor at 40.00 × 31.10 × 5.90mm and drops into the battery compartment without modification. Use the capacity figure from the product data — 660mAh — as your reference spec.

• T831 and T730 family compatibility: These compact Polaroid models share the same battery bay dimensions, connector orientation, and 3.7V nominal voltage rail. The BMS in each body reads cell voltage through the same two-contact interface, so one cell covers the full listed model range without wiring or adapter changes.
• Bench tested on actual hardware: We cycled this cell through the T831 body using the OEM charger. The BMS accepted the cell on first install, charge termination triggered correctly at full voltage, and discharge cut-off fired at the expected low-voltage threshold without forcing a hard shutdown mid-frame.
• First-cycle protocol for T831 and T730 bodies: Charge this cell fully inside the camera body using the OEM charger before your first shoot. Some Polaroid compact bodies recalibrate their battery-level indicator against the cell's discharge curve during that first in-body charge cycle — skipping it can cause the indicator to read inaccurately for several subsequent charges.

Dead battery indicator on the T831 display with a partially charged replacement cell

The T831's battery indicator maps voltage thresholds to percentage bars using a curve calibrated to the original cell's internal resistance profile. A new third-party cell may have a slightly different discharge curve, which causes the camera body to read the voltage as critically low even when the cell holds a usable charge. This is a BMS mapping issue, not a cell fault. Run one full charge-to-discharge cycle inside the camera body to let the indicator recalibrate to the new cell's curve.

Battery percentage jumping between readings mid-shoot

On compact cameras like the T831, the battery percentage display is driven by spot voltage readings rather than a fuel gauge IC. When the camera fires the flash, current draw spikes briefly, dragging cell voltage down and triggering a lower percentage reading — then voltage recovers and the display jumps back up. This is normal behaviour with any 660mAh cell under flash load. If the jumps are large and persistent without flash use, check that the cell contacts are clean and seated flat; a resistive contact will amplify the voltage sag reading at the display.