Cobra 72M Robotic Vacuum Compatible Battery 14.8V 1100mAh

Cobra 72M / 18M / 36M — 14.8V Li-Polymer Replacement Battery (ACE404567)

The ACE404567 is a 14.8V, 1100mAh (16.28Wh) lithium-polymer battery for the Cobra 72M, 18M, and 36M robotic vacuum cleaners. It slots into the underside battery bay and powers the motor, brush system, and onboard scheduling logic. When the original cell degrades, cleaning cycles shorten noticeably before the unit stops mid-run.

• 72M, 18M, and 36M compatibility: All three models run the same 14.8V four-cell Li-Polymer pack with an identical connector and BMS handshake protocol. Swapping between these models is straightforward — the voltage rail and communication lines match across the series.
• Bench tested on actual hardware: We cycled this pack through full discharge and charge sequences on the 72M platform. The BMS held charge termination correctly at 16.8V and tripped the undervoltage cutoff cleanly at 12.0V with no false shutoffs during motor-start draw.
• Post-install scheduling verification: After fitting the new battery, re-confirm any saved cleaning schedules in the app. The 72M's onboard memory clears its active schedule flag on a full power loss — the schedule data is retained in the app, but the unit needs it re-pushed before autonomous runs resume.

Cobra 72M stopping mid-cycle after a new battery install

A freshly installed ACE404567 shipped from storage may sit at 3.5–3.6V per cell — below the 72M's operating floor but above the BMS lockout threshold. The unit powers on, runs the brush motor for a short period, then cuts out as pack voltage sags under load. This is not a faulty battery. Run the unit on charge for a full cycle before the first cleaning run to bring all four cells to balance at 4.2V each.

Cobra 72M not returning to its dock after battery replacement

The 72M's dock-return routine relies on a capacitor-backed IR receiver circuit that resets when main battery power is interrupted. After fitting a replacement pack, the IR docking signal can misread until the circuit stabilises — typically within 90 seconds of the battery being connected. If the unit still misses the dock, place it manually on the dock contacts, allow a full charge cycle, then run a test clean from the app to re-calibrate the return path.