About this replacement
Cecotec Conga Immortal Extreme 05100 — 3.7V Li-ion Replacement Battery (INR18650)
This 3.7V 2600mAh (9.62Wh) Li-ion cell replaces the original INR18650 battery in the Cecotec Conga Immortal Extreme 05100 cordless vacuum. It powers the motor control board and suction unit directly. Fits the 05100 model and the broader Conga Immortal Extreme 3.7V platform.
- Conga Immortal Extreme 05100 platform: These models share a single INR18650 cell format with a direct motor drive rail at 3.7V nominal. The BMS monitors cell voltage and temperature — any replacement cell must match the original 18650 footprint and discharge curve to avoid mid-cycle cutoff.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the 05100 platform. The BMS accepted the cell without triggering fault codes, and the motor drew consistent current across both hard floor and carpet load profiles.
- Dock charging on the Conga 05100: Do not leave the vacuum sitting on the charging dock continuously. The Conga 05100 does not terminate charge aggressively — prolonged dock time trickle-charges the cell and accelerates capacity fade. Charge to full, then remove from the dock.
Cordless vacuum losing suction before the battery indicator reaches low
On the Conga 05100, the battery indicator reads remaining cell voltage — not remaining capacity under load. A degraded or partially discharged cell can show mid-charge on the indicator while the actual voltage under motor load sags below the BMS protection threshold. When that happens, the motor slows or cuts before the LED signals low battery. If suction drops early, check the filter first — a blocked filter forces the motor to draw above rated current, which accelerates voltage sag even on a healthy cell.
Motor cuts out mid-clean then recovers after a short pause
This is a BMS overcurrent trip, not a dead battery. The protection circuit on the INR18650 cell cuts the output when current spikes past a set threshold — most often caused by a restricted airflow path forcing the motor to work harder. The BMS resets automatically after the cell temperature drops, which is why the vacuum restarts after sitting for 30–60 seconds. Clear the filter and check the dust cup before assuming the battery is at fault — if the motor runs cleanly after cleaning the filter, the cell is not the problem.