Red Digital Cinema REDmote 645-0046 Compatible Battery 3.7V 2200mAh

Red Digital Cinema REDmote — 3.7V Li-ion Replacement Battery (645-0046)

This is a 3.7V, 2200mAh Li-ion cell built to fit the Red Digital Cinema REDmote wireless remote control. The REDmote pairs with RED cinema cameras to give operators remote control during production shoots. Voltage and capacity match the OEM spec exactly — 3.7V, 2200mAh (8.14Wh).

• REDmote platform fit: The REDmote uses a dedicated internal cell that must match the BMS voltage window and physical footprint. This cell measures 72.85 × 51.70 × 5.70mm — the same profile as the OEM unit — so the connector seats correctly and the remote powers on without a low-voltage rejection flag.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on REDmote-compatible test rigs. The BMS accepted the cell without a rejection event, and the remote's wireless link held stable across multiple test sessions at full draw.
• First-charge protocol for the REDmote: Run one full charge cycle from the REDmote's own charging port before taking it to set. Some remote BMS implementations recalibrate their state-of-charge estimate on the first full cycle — skipping this can cause the charge indicator to read inaccurately during your first production day.

REDmote showing dead battery on a freshly charged replacement cell

When a new Li-ion cell ships, its resting voltage often sits between 3.6V and 3.7V — not at full charge. The REDmote's BMS maps that voltage against its stored discharge curve, and if the cell hasn't completed a calibration cycle, the indicator can flag it as near-empty. This isn't a faulty cell. Plug the REDmote into its charger and run a complete charge cycle to 4.2V before use. After that first cycle, the BMS reads the cell correctly and the indicator stabilises.

Battery percentage jumping erratically on the REDmote display

The REDmote's charge indicator maps display percentage to voltage thresholds set during manufacture. A new replacement cell has a slightly different discharge curve shape than an aged OEM cell — the BMS hasn't learned it yet. This causes percentage values to skip or drop sharply rather than descend smoothly. Run two to three full charge-discharge cycles through the remote and the indicator mapping corrects itself. If jumping persists past three cycles, check that the cell is seated fully and the connector is making clean contact at the 3.7V nominal rail.