About this replacement
Sencor SPV7721 — 7.4V Li-Polymer Replacement Battery (GSP613762)
This 7.4V, 1900mAh Li-Polymer battery replaces the GSP613762 cell in the Sencor SPV7721 and SPV-7721T portable DVD players. It powers the display, disc motor, and onboard audio simultaneously. Capacity figure is 14.06Wh at rated voltage.
- SPV7721 and SPV-7721T fit: Both models share the same battery bay dimensions (64.40 × 36.50 × 12.10mm), the same 7.4V supply rail, and the same GSP613762 part number — one cell covers both.
- Bench tested on actual hardware: We cycled the cell through full charge and playback load. The BMS held steady voltage across the disc motor spin-up draw and display backlight without triggering low-voltage cutoff.
- First-use charge on portable DVD players: Li-Polymer cells ship at storage voltage — typically 3.7–3.8V per cell. The SPV7721 may refuse to start or show an immediate low-battery indicator if you skip the initial full charge. Charge completely before first playback session.
Disc not spinning after battery replacement in the SPV7721
The disc motor in the SPV7721 draws a short burst of peak current at spin-up — higher than the steady draw during playback. If the battery voltage is still at storage level, that burst can pull the cell below the BMS cutoff threshold before the disc reaches operating speed. The player then shows no disc or freezes at the loading screen. A full charge cycle before use raises the cell voltage high enough to handle the spin-up surge without tripping protection.
Screen dimming mid-movie on the SPV7721
The SPV7721's display driver monitors supply voltage and steps down backlight current when the battery sags below roughly 6.8V under combined disc and display load. This shows up as a gradual dim that gets worse toward the end of playback. It is not a screen fault — it is the display circuit protecting itself from undervoltage. Avoid charging and playing simultaneously where possible, as the combined draw accelerates voltage sag. If dimming starts earlier than expected on a new battery, check that the cell reached a full charge before use.