Insta360 X4 Air CINSBAFA Replacement Battery 3.89V 2000mAh

Insta360 X4 Air — 3.89V Li-ion Replacement Battery (CINSBAFA)

This is a 3.89V, 2000mAh Li-ion battery for the Insta360 X4 Air action camera. It replaces OEM part CINSBAFA and fits the X4 Air body directly. Voltage and capacity match the original cell specification.

• X4 Air platform fit: The X4 Air uses a specific cell footprint and BMS handshake tied to the CINSBAFA part. This replacement matches that footprint and communicates with the camera's power management IC at the correct voltage rail — 3.89V nominal — so the body accepts the cell without rejection flags on a properly cycled install.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on X4 Air hardware. The BMS accepted the cell, reported charge state through the camera display, and held voltage above the low-battery cutoff threshold through full discharge without triggering premature shutdown.
• First-use charge cycle on X4 Air: Charge the new cell fully inside the camera body using the OEM USB-C connection before your first shoot. Some X4 Air units need one complete in-body charge cycle to map the new cell's discharge curve correctly — skipping this step can cause the battery percentage indicator to read inaccurately from the start.

Why the X4 Air battery percentage jumps or reads 100% then drops suddenly

The X4 Air maps remaining battery percentage against a voltage-threshold table calibrated to the original cell's discharge curve. A new replacement cell may have a slightly different discharge profile at the same nominal voltage, causing the indicator to snap between values rather than step down smoothly. This is a calibration issue at the camera firmware level, not a cell fault. Running one full charge-to-empty cycle in the camera body allows the BMS to recalibrate its threshold mapping to the new cell.

X4 Air showing "no battery" or refusing to power on with a replacement cell installed

The X4 Air performs a BMS authentication check when a new cell is seated. If the camera has not completed a charge handshake with the new cell, it may display a no-battery warning or refuse to boot entirely. Seat the battery firmly, then connect the camera to a charger via USB-C before attempting to power on — this initiates the handshake sequence. Once the charge indicator appears on screen, disconnect, then power the camera on normally. If the body still rejects the cell, check that the gold contact pins on the battery are clean and fully engaged with the camera's battery compartment contacts.