About this replacement
Cecotec Conga 4090 / 4490 / 4590 / 4690 — 14.8V Li-ion Replacement Battery (05424)
This 14.8V 5200mAh Li-ion battery replaces the original power cell in the Cecotec Conga 4090, 4490, 4590, and 4690 robotic vacuum cleaners. It matches the OEM voltage and capacity spec exactly — 76.96Wh. When the original battery degrades after repeated charge cycles, suction weakens and cleaning runs shorten — this cell restores full operating capacity.
- Conga 4090 / 4490 / 4590 / 4690 compatibility: These four models share the same battery bay dimensions, 14.8V four-cell Li-ion configuration, and BMS handshake protocol — the same cell fits all four without modification.
- Bench tested on actual hardware: We ran this battery through charge and discharge cycles on the Conga 4090 platform. The BMS responded correctly to the robot's charge termination signal and did not trip under normal suction load on both hard floor and carpet modes.
- Dock charging habit for Conga robots: Do not leave the Conga sitting on its dock permanently between cleans. Continuous trickle charging causes capacity fade significantly faster than cycling the battery through full discharge and charge. Charge fully, then remove from dock until the next clean.
Suction dropping before the battery indicator reaches low
This happens when the motor is working harder than rated — usually because a partially blocked filter forces it to draw excess current. Under that load, voltage sags at the cell level even when nominal charge looks fine. The BMS reads a voltage dip and throttles power to the motor before the indicator registers a low-battery state. Clean or replace the filter first; if suction recovers to normal strength, the battery is not the cause.
Motor cuts out mid-clean and then recovers after a short pause
This is a BMS overcurrent trip, not a dead battery. When suction airways are restricted — blocked brush roll, clogged filter, or a jammed side brush — the motor draws current above the BMS threshold and the pack shuts off briefly to protect the cells. After a short cooldown the BMS resets and power returns. Clear any blockage and check that the filter is seated correctly; if the cut-outs stop, the battery is operating as intended.