About this replacement
Angelcare AC517 / AC417 / AC510 — 3.7V Li-Polymer Replacement Battery (1ICP5/54/57)
This 3.7V, 1800mAh Li-Polymer battery replaces the original cell in the Angelcare AC517, AC417, AC510, and AC315 parent units. The parent unit is the handheld display you carry around the house — it runs entirely on this battery when unplugged. If yours no longer holds a charge or dies quickly, this is the cell to swap.
- AC517 / AC417 / AC510 / AC315 compatibility: These models share the same parent unit platform, the same 3.7V single-cell architecture, and the same 1ICP5/54/57 cell format. The connector and PCB footprint match across the range, so one cell covers all four.
- Bench tested on actual hardware: We cycled this cell through the AC517 parent unit and confirmed the BMS accepted charge from the stock charging cradle without fault codes. Charge current ramped correctly through CC/CV stages with no thermal events at the cell.
- Re-pair after power loss: When the parent unit drops to zero voltage — as it will during a battery swap — it loses its wireless link to the camera unit. After fitting this battery and charging, re-initiate the pairing sequence from the parent unit menu before expecting the video or audio feed to return.
Parent unit range dropping after battery replacement
The AC517 parent unit's 2.4GHz radio transmit power is directly tied to rail voltage. A freshly installed cell that hasn't completed its first full charge will sit below 3.7V nominal, and the radio will run at reduced output. This shows up as dropouts or a shortened range that wasn't there before the swap. Charge the parent unit fully on the cradle — until the indicator shows 100% — before doing a range test. A fully charged cell should hold 4.1–4.2V at rest.
Parent unit battery draining faster than expected overnight
Night mode with the screen active is a sustained draw on a 1800mAh cell — the backlit display is the single largest consumer in the parent unit. The AC517 has a screen timeout setting in the display menu; leaving it disabled keeps the LCD lit continuously through the night. Enable the screen timeout so the display goes dark between sound alerts. If drain is still abnormal after that change, check that the VOX sensitivity isn't triggering constant wake events from ambient noise in the nursery.