About this replacement
Logitech Circle 2 — 3.7V Li-ion Replacement Battery (533-000145)
This 3.7V Li-ion battery replaces the original cell in the Logitech Circle 2 wireless home security camera. It fits the Circle 2 across its indoor and outdoor configurations, including models listed as ICES-3(3), NMB-3(B), and V-U0045. Capacity is 6800mAh (25.16Wh), matching the original specification.
- Circle 2 platform fit: All Circle 2 variants share the same 3.7V single-cell architecture and the same physical cell format. The BMS communicates with the camera firmware over a shared voltage rail — the connector and cell dimensions are identical across indoor and wired-free outdoor units, so this cell fits without modification.
- Bench tested on actual hardware: We cycled this cell through motion-trigger events, including sustained IR LED activation during simulated night conditions. The BMS held voltage within the camera's accepted range and did not trip on the combined processor and IR draw spike.
- First-install power cycle: After fitting this cell, power cycle the camera once through the Logitech app before relying on motion recording. The firmware must register the new cell's voltage baseline before it logs motion events correctly to cloud storage — skipping this step can cause the first few triggers to drop silently.
App showing 0% or incorrect battery percentage after cell swap
The Circle 2 uses a voltage-threshold indicator, not a fuel gauge IC. When a new cell is installed, the camera reads the resting voltage and maps it to a percentage — but the indicator needs one full charge-to-discharge cycle to calibrate correctly. Until that cycle completes, the app may display 0%, a frozen percentage, or a figure that doesn't match actual charge state. Run the camera on battery until it prompts a low-battery warning, then charge fully to 4.2V to resolve the mismatch.
Recording stops mid-clip when WiFi signal is weak
When the Circle 2 loses and re-establishes a WiFi connection mid-recording, the radio draws a sharp current spike to reconnect. On a degraded original cell, that spike can push the battery voltage below the BMS cutoff threshold, ending the clip abruptly. This replacement cell holds voltage more consistently under that transient load. If mid-clip dropouts continue, move the camera closer to the access point or check that the router channel isn't congested — the fix is reducing reconnect frequency, not the cell itself.