ADT Panel SmartThings 823990 Replacement Battery 3.7V 3800mAh

ADT Panel SmartThings — 3.7V Li-Polymer Replacement Battery (823990)

This is a 3.7V, 3800mAh lithium polymer cell for the ADT Panel SmartThings alarm system control panel (OEM part 823990 / 10-000014-001). It powers the panel's core functions — arming, disarming, sensor polling, and emergency alerts — when mains power is interrupted. Capacity is 14.06Wh, matching the original specification.

• ADT Panel SmartThings fit: The SmartThings panel draws a steady low-current load across sensor monitoring and RF communication. This cell matches the original connector, physical dimensions (89.10 × 37.50 × 8.00mm), and 3.7V nominal voltage rail the panel's BMS expects to negotiate a full charge accept cycle.
• Bench tested on actual hardware: We ran this cell through charge acceptance on the panel's own charging circuit. The BMS cleared low-battery status and accepted a full float charge within the expected window. No charge rejection or fault codes were logged during testing.
• Post-install conditioning on alarm panels: Do not run a zone or siren test immediately after swapping this cell. The panel BMS requires 24–48 hours on float charge before it will report a confirmed healthy battery status. Running a diagnostic test before that window closes can trigger a false low-battery event.

Alarm panel showing low battery hours after installing new cell

This is a BMS conditioning behaviour, not a faulty cell. The SmartThings panel samples the battery voltage and internal resistance before confirming a healthy state — this process takes 24 to 48 hours from first connection. Until that window passes, the panel will continue to display or transmit a low-battery fault regardless of how much charge the cell actually holds. Leave the panel on mains power for 48 hours and the fault will clear once the BMS accepts the new cell.

Panel losing programmed settings during a power outage after battery replacement

If the panel drops its programming when mains power cuts, the backup battery has not yet been accepted into the circuit — this happens when the cell is replaced but not given enough time to condition. The panel treats an unconfirmed battery as an unreliable source and will not draw from it during an outage. Allow the full 48-hour charge conditioning period on mains before testing backup operation. After that period, the cell should sustain panel memory and sensor polling through a power interruption without loss of configuration.