Spare MiniDVR 3 Replacement Battery 3.7V 1100mAh Li-ion

Spare MiniDVR 3 / H720 — 3.7V Li-ion Replacement Battery (US804533A1T4)

This is a 3.7V, 1100mAh Li-ion cell for the Spare MiniDVR 3 and H720 compact digital video recorders. It replaces OEM part US804533A1T4 directly. The cell measures 53.10 × 38.40 × 8.00mm and fits the original battery bay without modification.

• MiniDVR 3 and H720 platform fit: Both devices share the same battery bay dimensions, connector pinout, and 3.7V single-cell architecture. One cell covers both units.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on a MiniDVR 3 body. The BMS accepted the cell without error flags, and voltage held steady across standard recording loads.
• First-install charge cycle on miniature DVR bodies: Run a full charge through the device's own USB charging circuit before first use. Some compact DVR BMS implementations need an in-body charge cycle to calibrate the battery-remaining indicator accurately — charging externally first can leave the display reading off by 20–30%.

Why the MiniDVR 3 shows a dead-battery indicator on a freshly installed replacement cell

Compact DVR bodies like the MiniDVR 3 often use a simple voltage-threshold method to estimate charge level. A new cell shipped in storage mode can sit at 3.5–3.6V — below the threshold the firmware treats as "usable." The body reads this as empty and may refuse to start recording. Connecting to USB power for a full charge cycle resets this: once the cell reaches 4.2V and the BMS logs the full charge event, the indicator updates correctly.

Battery percentage jumping erratically on the MiniDVR 3 display

This happens when the device's discharge curve map doesn't match the new cell's actual voltage profile. The firmware expects specific voltage steps at specific states of charge — if the cell's curve differs slightly, the indicator skips or jumps. It typically stabilises after two or three full charge-discharge cycles as the BMS learns the new cell's curve. If jumping persists past three cycles, check resting voltage with a multimeter: a healthy cell at 50% charge should read between 3.75V and 3.85V.