About this replacement
Ecovacs AZ1 / Airbot Z1 — 18V Li-ion Replacement Battery (201-2109-0675)
This 18V, 5200mAh (93.6Wh) Li-ion battery replaces the original pack in the Ecovacs DEEBOT AZ1 and Airbot Z1 robotic vacuum cleaners. It fits directly into the battery bay and communicates with the onboard BMS using the S18-Li-180-5200 compatible cell configuration. Swap it in when the original pack can no longer hold a charge or the robot stops mid-clean.
- AZ1 and Airbot Z1 platform fit: Both models share the same 18V battery bay, connector pinout, and BMS handshake protocol. This replacement carries the matching OEM part references 201-2109-0675 and S18-Li-180-5200, so the robot's charge management system recognises the pack and allows normal operation.
- Bench tested on actual hardware: We cycled this pack through load tests replicating carpet and hard-floor suction motor draw. The BMS held voltage within spec under sustained load and triggered overcurrent protection correctly when current spiked beyond safe limits.
- Dock charging habit on the AZ1: Do not leave the AZ1 sitting on its dock continuously after a full charge is reached. Robotic vacuums left on permanent trickle charge develop capacity fade significantly faster than those removed from the dock once fully charged. Charge to full, then remove.
Suction dropping before the battery indicator reaches low on the AZ1
This happens when the motor has to work harder than rated — most often because the filter is partially blocked or the dustbin is full. The motor draws more current to maintain suction, which pulls cell voltage down early. The BMS reads that voltage sag as low battery and begins throttling power before the indicator would normally trigger. Clean the filter and empty the bin, then check whether the pack holds above 16V under load during a cleaning run.
AZ1 motor cutting out mid-clean and then recovering after a short pause
This is a BMS overcurrent trip, not a dead battery. When airflow is restricted — blocked brush roll, clogged filter, or hair wrapped around the intake — the motor draws a sustained current spike the BMS treats as a fault. It cuts power momentarily, the motor cools slightly, and the BMS resets. The robot appears to recover but the fault repeats. Clear the restriction first. If the cut-outs continue after the filter and brush roll are clean, check cell voltage at rest — a healthy pack should read at or above 18V fully charged.