About this replacement
Babysense BBM01 / BBM03 / HD S2 — 3.7V Li-Polymer Replacement Battery (UT905560P)
This is a 3.7V, 4000mAh Li-Polymer battery for the Babysense parent unit. It fits the BBM01, BBM03, Bonoch BBM05, and HD S2 Video Baby Monitor. OEM part number UT905560P confirms the match across all four models.
- BBM01, BBM03, BBM05, and HD S2 compatibility: These parent units share the same battery bay dimensions, connector pinout, and 3.7V voltage rail. The BMS handshake is identical across the range, so one cell fits all four without modification.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the parent unit. The BMS accepted the full 4000mAh capacity without flagging a fault, and voltage held steady through both screen-on and screen-off loads.
- Screen timeout after battery swap: Baby monitor parent units keep the display lit by default. After fitting this battery, set the screen timeout in the menu before overnight use — continuous screen-on draw will pull the cell down faster than standby mode alone.
Parent unit not connecting to the camera after battery swap
Babysense parent units lose their stored wireless pairing when power drops to zero — which happens during a battery replacement. The unit does not automatically re-pair on first boot with a new cell. Hold the pair button on both the camera unit and the parent unit simultaneously until the link indicator confirms connection. This step is required every time the parent unit loses power completely.
IR night vision failing after fitting the new battery
The infrared LEDs on the camera unit draw power from the camera's own supply, but the parent unit's receiver circuit needs adequate voltage to process and display the IR feed correctly. If night vision appears black or grainy immediately after a swap, the new cell may not yet be at full charge. Charge the parent unit to 4.2V before testing night vision. A partially charged Li-Polymer cell can cause display artefacts under sustained IR load.