About this replacement
Ezviz DB2C — 3.7V Li-ion Replacement Battery (18650-03)
This is a 3.7V, 5200mAh (19.24Wh) Li-ion replacement battery for the Ezviz DB2C wireless video doorbell. It slots into the DB2C housing and powers the camera, motion detection, and two-way audio system. Capacity matches the original 18650-03 cell specification.
- DB2C platform fit: The DB2C uses a single-cell 3.7V Li-ion pack with a specific connector and BMS handshake. This replacement matches that voltage rail and connector pinout so the doorbell's firmware recognises the cell and reports charge state correctly through the Ezviz app.
- Bench tested on actual hardware: We cycled this battery through the DB2C's motion-trigger sequence, including night vision activation and two-way audio simultaneously. The BMS handled the combined IR LED and processor current spike without tripping into protection mode.
- First-install power cycle: After fitting this battery, power cycle the doorbell once through the Ezviz app. The firmware must register the new cell before motion events log correctly to cloud storage — skipping this step can cause missed recordings on the first night.
Why the DB2C goes offline in the Ezviz app after a battery swap
When the DB2C loses power completely during a battery change, the device drops its active session token with the Ezviz cloud server. The camera comes back online physically but the app loses its registered connection. This shows as the device being "offline" even though the LED on the doorbell is active. Fix this by opening the Ezviz app, going to Device Settings, and running a soft restart — the camera re-registers within about 30 seconds and resumes live view.
App reporting 0% or frozen charge percentage after battery install
The DB2C uses a voltage-threshold indicator, not a fuel-gauge IC. After fitting a new cell, the firmware maps the resting voltage to a percentage using stored thresholds — if the battery sits near a threshold boundary, the app can display 0% or a stale value. Run the doorbell through one full discharge and charge cycle to let the firmware re-anchor its voltage-to-percentage mapping. After the cycle completes, the displayed percentage should track accurately from 4.2V full down to the low-voltage cutoff at approximately 3.0V.