Angelcare AC320 Replacement Battery 3.7V 1800mAh

Angelcare AC320 / AC327 / AC337 / AC527 — 3.7V Li-Polymer Replacement Battery

This 3.7V 1800mAh Li-Polymer battery replaces the parent unit battery in the Angelcare AC320, AC327, AC337, and AC527 baby monitors. It fits the slim parent unit housing directly — same dimensions at 60 x 57 x 5.3mm. If your parent unit no longer holds a charge or dies mid-session, this is the direct swap.

• AC320 / AC327 / AC337 / AC527 compatibility: These four models share the same parent unit platform, connector type, and battery bay dimensions. The 3.7V nominal voltage matches the internal power rail on all four — no adapter or modification needed.
• Bench tested on actual hardware: We ran this battery through full charge and discharge cycles on the parent unit. The BMS handled charge termination cleanly at 4.2V and held stable output through both screen-on and audio-transmission loads without tripping the protection circuit.
• Re-pair after installation: Angelcare parent units lose their stored wireless link when power is fully interrupted. After fitting this battery, you will need to re-pair the parent unit with the camera unit before monitoring resumes — keep the camera unit nearby during first power-on.

Parent unit battery draining overnight on the AC320

Running the AC320 parent unit overnight with the screen on is a sustained high draw. The backlit display and active audio receiver together pull significantly more current than audio-only standby mode. Even a fresh 1800mAh cell will show a meaningful drop by morning under those conditions. Use the screen timeout setting in the parent unit menu to cut display draw during overnight monitoring.

Night vision stops working after fitting a new battery

The AC320 camera unit's IR LEDs are powered by the camera's own supply, but the parent unit needs sufficient voltage on its radio receiver to decode the night-vision video stream correctly. If the parent unit battery ships partially discharged — common with Li-Polymer cells in transit — the display may show a blank or broken image in low-light mode. Charge the parent unit fully before testing night vision. A full charge brings the cell to 4.2V and resolves the majority of post-swap IR display issues.