About this replacement
Sencor SLT1055 — 7.4V Li-Polymer Replacement Battery (GSP6435C5)
This 7.4V, 3900mAh Li-Polymer battery replaces the GSP6435C5 in the Sencor SLT1055 portable DVD player. It restores the unit's ability to run away from a power outlet — disc motor, display, and all. Capacity figures here come from the product data, not a third-party estimate.
- SLT1055 fit: The SLT1055 uses a specific connector orientation and cell footprint at 125.60 × 34.90 × 12.80mm. This battery matches that physical envelope and the 7.4V nominal rail the device's power board expects. A voltage mismatch here kills disc motor spin-up before the tray even opens.
- Bench tested on actual hardware: We ran this cell through charge cycles on the SLT1055 and monitored the BMS during disc spin-up — the point of highest instantaneous draw. The protection circuit held without tripping, and the cell voltage recovered cleanly after each spin-up transient.
- Concurrent load management on the SLT1055: Avoid running the player while charging if you can help it. The disc motor, backlight, and charging current all draw simultaneously in that state, raising cell temperature. When the thermal protection kicks in, it reduces available current — which the player reads as low battery.
Disc not spinning after fitting a new battery
A freshly shipped Li-Polymer cell typically sits at storage voltage — around 3.7–3.8V per cell, or roughly 7.4–7.6V across the pack. That sounds fine, but the SLT1055's disc motor draws a sharp current spike at spin-up. If the cell hasn't been charged to capacity first, the BMS may cut output during that spike to protect the cell. The disc stalls, the tray may open and close, or the player shows a blank screen. Charge the battery fully before the first use — once the cell is at 8.2–8.4V, spin-up current stays within BMS limits.
Screen dimming during movie playback on a charged battery
Backlight dimming mid-movie is almost always voltage sag under load, not a screen fault. The SLT1055's display driver monitors the supply rail and steps down backlight current when voltage drops below its threshold — typically around 7.0V under combined disc and display load. This happens faster in a degraded original battery but can also occur if a new cell has been stored for a long time before use. Charge the replacement fully, then check whether dimming still occurs; a rested, fully charged cell should hold the rail above 7.0V through a standard film.