Phisung HDV-D505SC Dash Camera Replacement Battery 3.7V 720mAh

Phisung HDV-D505SC — 3.7V Li-ion Replacement Battery

This 3.7V 720mAh (2.66Wh) Li-ion cell replaces the original internal battery in the Phisung HDV-D505SC dash camera. The HDV-D505SC is a vehicle-mounted recording device used for continuous road footage capture. When the original cell loses capacity or fails to hold charge, this replacement restores normal recording operation.

• HDV-D505SC fit: The HDV-D505SC uses a slim 5.60mm cell at 3.7V nominal — the same voltage rail the camera's BMS expects to recognise a valid cell on startup. Physical dimensions are 39.50 × 35.40 × 5.60mm, matching the original bay without modification.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a calibrated rig. The BMS handshake completed normally on first connect. Cell voltage held within expected tolerances across the full discharge curve.
• Dash camera loop-recording draw: The HDV-D505SC writes continuously to the card while the vehicle is running. Avoid removing power mid-write — always let the camera complete its file save cycle before cutting power to prevent corrupted footage segments.

Why the HDV-D505SC shows a dead battery indicator on a fresh replacement cell

The HDV-D505SC maps its battery indicator to voltage thresholds calibrated during manufacture against the original cell's discharge curve. A new replacement cell shipped at storage voltage — typically around 3.6–3.7V — can read as critically low or empty on the camera's display even when the cell is not depleted. Performing one full charge cycle through the camera before relying on the indicator resets this mapping. After that first cycle, the display accurately reflects remaining capacity.

Battery percentage jumping erratically on the HDV-D505SC display

This happens when the camera's voltage-to-percentage translation doesn't yet match the new cell's discharge curve. The original cell's curve is baked into the firmware thresholds — a replacement cell with slightly different internal resistance reads as a different voltage under load, causing the indicator to skip steps. The fix is two full charge-discharge cycles through normal camera use. After cycling, the readings stabilise because the BMS has sampled enough voltage-load points to interpolate accurately.