Cisco M2120 Replacement Battery 3.7V 1000mAh Li-ion

Cisco M2120 / F360 Series — 3.7V Li-ion Replacement Battery

This is a 3.7V, 1000mAh Li-ion replacement battery for the Cisco M2120, M2120M, F360, and F360B cameras. It matches the original cell's voltage, capacity, and physical dimensions — 52.58 x 34.10 x 5.60mm — so it seats correctly in the battery compartment. Replace this when the original cell no longer holds a useful charge or fails to power the camera on.

• M2120 and F360 platform fit: The M2120, M2120M, F360, and F360B share the same battery bay dimensions and 3.7V voltage rail, which is why one cell covers all four models. The connector orientation and BMS handshake protocol are consistent across this Cisco camera family.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on compatible hardware and confirmed the BMS accepted the new cell without fault codes. Charge acceptance was normal from the first cycle, and the protection circuit responded correctly to cutoff thresholds at both ends of the voltage range.
• First-cycle calibration on the M2120: After fitting the new cell, run one complete charge cycle inside the camera body using the OEM charger or USB source before your first shoot. Some Cisco M2120 units need this initial in-body charge cycle to map the new cell's discharge curve and display battery-remaining accurately.

Why the M2120 shows a dead-battery indicator on a partially charged replacement cell

The M2120 maps its battery indicator to a voltage-threshold table stored from the original cell's discharge curve. A new cell with a slightly different internal resistance will hit those thresholds at different state-of-charge points, making the indicator read low or empty even when the cell still has capacity. This is a calibration mismatch, not a faulty battery. One full charge-discharge cycle inside the camera body resets the mapping and brings the indicator back into alignment with the actual cell state.

Camera body warm during sustained video recording on the M2120

The M2120's sensor, image processor, and stabilisation circuits draw simultaneously during video, which pulls more current from the 1000mAh cell than still-capture does. At high sustained draw, the cell's internal temperature rises and the BMS may throttle output to stay within safe limits — this is normal protection behaviour, not a defect. If the camera body feels warm and frame rate drops, pause recording briefly to let the cell temperature recover. Avoid recording in direct sunlight, as ambient heat reduces the BMS thermal headroom further.