About this replacement
iRobot Braava Jet M6 Series — 10.8V Li-ion Replacement Battery (ALB-C)
This 10.8V, 2000mAh Li-ion battery replaces the ALB-C cell used in the iRobot Braava Jet M6 floor-cleaning robot. It fits the M611020, M612880, and M612680 alongside other M6 variants. Swap it when the original no longer holds enough charge to complete a cleaning run.
- M6 series compatibility: All listed M6 variants share the same 10.8V three-cell architecture, connector pinout, and BMS handshake protocol. The robot's firmware reads charge state through the battery's onboard BMS — any cell that breaks that communication loop will trigger a fault light regardless of actual charge level.
- Bench tested on actual hardware: We cycled this cell through full charge and discharge on the M6 platform and confirmed the BMS negotiates correctly with the robot's charge controller. The protection circuit tripped at the expected low-voltage cutoff without triggering false fault codes.
- Dock storage on the M6: The Braava Jet M6 is marketed as a dock-and-forget device, but leaving it seated on the charging dock between every use accelerates capacity fade. Remove the robot from the dock once charging completes and only redock before a scheduled clean.
Why the Braava Jet M6 reports a battery fault on a freshly charged cell
The M6 does not just measure voltage — it expects a BMS that responds to its handshake during the charge cycle. A cell with a non-communicating or mismatched protection circuit will cause the robot to flash its battery indicator even when the pack is fully charged. This is a communication failure, not a capacity failure. Aftermarket cells that replicate the ALB-C BMS protocol clear this fault without any firmware workaround.
M6 powers on but stops mid-clean and will not restart immediately
This is the BMS tripping on a sustained current spike — most commonly caused by the robot's pump or vibrating pad motor drawing above the cell's continuous discharge limit. A clogged water tank nozzle or worn pad forces the pump to work harder and pulls excess current. The BMS latches off to protect the cell and the robot sits unresponsive until the pack cools and the protection circuit resets. Clear the nozzle, inspect the pad, and allow two minutes before powering the robot back on.