Kärcher 9.766-461.0 Replacement Battery 10.8V 2000mAh

Karcher 9.766-461.0 — 10.8V Li-ion Replacement Battery

This 10.8V 2000mAh Li-ion battery replaces part number 9.766-461.0 in Kärcher cordless handheld vacuum cleaners. It matches the original voltage rail and connector, so it slots into the same bay and communicates with the same BMS. Capacity is 2000mAh (21.6Wh), identical to the factory cell.

• Kärcher handheld vacuum platform: These compact vacuums run a 10.8V nominal cell matched to a motor tuned for that voltage rail. Swapping to a mismatched voltage stresses the BMS and trips overcurrent protection — this cell stays on spec.
• Bench tested on actual hardware: We cycled this cell through charge and discharge passes on a Kärcher-compatible dock. The BMS accepted charge handshake on the first connection and held cutoff voltage at the correct low-cell threshold without triggering false protection trips.
• Dock charging discipline on Kärcher handhelds: Do not leave the vacuum seated on the charging dock permanently. Continuous dock contact on these units applies a slow trickle that compresses cell capacity over weeks. Charge to full, then remove from the dock.

Cordless vacuum losing suction before the battery indicator reaches low

This is a voltage sag issue, not a capacity failure. When the filter is partially blocked, the motor has to work harder and draws more current than its rated load. That current spike drops the cell voltage faster than the indicator circuit tracks, so the motor starves before the LED shows anything. Clean or replace the filter first — if suction returns to normal, the cell is not the cause. If the motor still sags on a clean filter, the cell has lost enough internal resistance tolerance that voltage under load dips below 9V and the BMS intervenes.

Motor cuts out mid-use then recovers after a short pause

This is a BMS overcurrent trip, not a dead battery. Sustained restricted airflow — a clogged filter or blocked nozzle — forces the motor to draw current past the BMS protection threshold, which shuts the output rail. The BMS resets after the cell voltage recovers, which is why the vacuum restarts after 30–60 seconds. Clear the blockage before replacing the battery. If the cutout persists on a clear filter with a new cell, measure resting cell voltage after a full charge — it should read 12.4V to 12.6V before the BMS trips again.