Vivitar BLI-885 DVR-850W Replacement Battery 3.7V 750mAh

Vivitar DVR-850W / ViviCam 8027 — 3.7V Li-ion Replacement Battery (BLI-885)

This is a 3.7V, 750mAh Li-ion cell that replaces the BLI-885 in the Vivitar DVR-850W, DVR850W, V8027, and ViviCam 8027 compact camcorders. It fits the same slot as the original and connects through the same 3-pin interface. Capacity comes straight from the product data: 750mAh / 2.78Wh.

• DVR-850W and ViviCam 8027 compatibility: Both models draw from the same 3.7V rail and use identical connector pinouts and BMS handshake protocols — one cell covers the full group without modification.
• Bench tested on actual hardware: We cycled this cell through charge and full discharge on DVR-850W hardware. The BMS accepted the charge current without cutoff, and the protection circuit tripped correctly at the low-voltage threshold.
• Fuel gauge recalibration on first install: After fitting this cell, run one complete discharge to auto-shutoff, then charge uninterrupted to 100% before recording. The camcorder's fuel gauge IC is calibrated to the old cell's discharge curve — one full cycle resets it to the new cell's profile.

Why the DVR-850W shows wrong battery percentage after a cell swap

The DVR-850W tracks charge state using a coulomb counter that was trained on the original cell's impedance and discharge curve. A new cell has different internal resistance, so the counter's model no longer matches actual cell voltage. The firmware reads a voltage that maps to one percentage on the old curve but sits at a different true state-of-charge on the new cell. One full discharge-to-shutoff followed by a full uninterrupted charge forces the counter to rebuild its reference points against the new cell.

Camcorder won't power on after the battery sat in storage

Li-ion cells left discharged for extended periods can drop below 2.5V per cell, which triggers the BMS protection circuit into a hard lockout state. In lockout, the cell looks dead — no response to the power button, no charge indicator. Connect the camcorder to its charger and leave it for 30–45 minutes without pressing anything; most BMS circuits use a trickle pre-charge path at around 0.1C to recover cells between 2.5V and 3.0V before allowing normal charge current. If the charge LED activates within that window, the cell is recovering.