About this replacement
Ring Alarm Home Base Pro Station — 7.4V Li-ion Replacement Battery (5E42E9)
This is a 7.4V 3400mAh Li-ion battery for the Ring Alarm Home Base Pro Station. It slots into the hub's internal backup compartment and keeps the security system online when mains power drops. The OEM part number is 5E42E9.
- Ring Alarm Home Base Pro compatibility: The Pro Station uses a dedicated 7.4V cell with a BMS handshake that communicates charge state directly to the Ring app. Voltage, connector type, and cell dimensions must all match the original spec — this battery meets all three.
- Bench tested on actual hardware: We ran this cell through a full charge cycle on the Home Base Pro and confirmed the BMS accepted the battery without fault codes. The hub reported charge status correctly via the Ring app within the expected window.
- Float charge conditioning after installation: Do not run a diagnostic test or trigger a zone test immediately after fitting this battery. The panel BMS requires 24–48 hours on float charge before it accurately reports full capacity — testing too early may generate a false low-battery alert in the Ring app.
Alarm panel losing programming during a power outage after battery replacement
If the Home Base Pro loses its configuration during an outage shortly after a battery swap, the new cell has not yet been fully accepted by the panel's BMS. The hub needs continuous mains power for 48 hours post-installation to complete the battery conditioning cycle. Until that cycle finishes, the backup cell may not hold enough charge to sustain the panel through an outage. Keep the hub on mains for 48 hours before testing backup behaviour.
Ring app shows "Low Battery" immediately after fitting a new cell
This is a BMS reporting lag, not a faulty battery. The Home Base Pro's internal charge monitor does not update the app until the cell has been on float charge for 24–48 hours after installation. The hub is still functional during this period — the low-battery flag is a status read from a cell the BMS has not yet fully characterised. Leave the hub connected to mains and the alert will clear once the float charge cycle completes at 8.4V terminal voltage.