Ezviz C3A Wireless Camera Compatible Battery 3.8V 5500mAh

Ezviz C3A — 3.8V Li-Polymer Replacement Battery (BL-BC-01)

This 3.8V, 5500mAh (20.9Wh) Li-Polymer battery replaces the original BL-BC-01 cell in the Ezviz C3A wireless security camera. It fits directly into the C3A's battery compartment and connects to the same power management circuit. The C3A runs entirely on this cell — no wired backup — so a degraded battery means the camera goes dark.

• C3A power circuit: The C3A pulls current in sharp spikes — the processor, Wi-Fi radio, and IR LEDs can all draw simultaneously during a motion event. The BMS on this cell is rated to handle that combined spike without tripping into protective cutoff, which is exactly where degraded original cells fail.
• Bench tested on actual hardware: We cycled this battery through repeated motion-trigger events, logging voltage behaviour across IR activation, Wi-Fi reconnect, and simultaneous recording. The BMS held steady through each combined-draw spike with no mid-clip cutoff.
• First-install power cycle: After fitting the new battery, power cycle the camera once through the Ezviz app. The firmware must re-register the cell before motion events log correctly to cloud storage — skipping this step can cause missed clips even when the camera appears online.

Why the C3A drops offline in the app after a battery swap

Swapping the battery cuts power to the C3A's Wi-Fi module, which invalidates the active session token stored in firmware. The camera comes back online at the hardware level but the Ezviz app still sees a stale session and shows the device as offline. A manual re-registration through the app — not just a refresh — clears the token and re-links the camera to your account. If the camera remains offline after that, check the battery contacts are fully seated, as a loose connection can cause intermittent power drops the app reads as a disconnection.

App showing 0% or wrong battery percentage after install

The C3A uses a voltage-threshold indicator, not a fuel gauge IC. It estimates charge level by measuring cell voltage against fixed thresholds rather than tracking coulombs. A new cell installed at partial voltage can confuse this system and report 0% or an incorrect figure. Run the camera through one complete charge and discharge cycle — charge to full, let normal camera operation draw it down — and the voltage readings will recalibrate to display an accurate percentage.