Karcher 1.055-363.0 Compatible Battery 7.4V 2500mAh

Karcher FC 3d Cordless Series — 7.4V Li-ion Replacement Battery (4.683-274.0)

This is a 7.4V, 2500mAh Li-ion replacement battery for the Karcher 1.055-363.0, FC 3d Cordless, and FC 3d Cordless Premium. It fits the OEM battery slot directly and communicates with the device's onboard charging circuit. Capacity matches the original at 2500mAh (18.5Wh).

• FC 3d Cordless platform compatibility: The 1.055-363.0, FC 3d Cordless, and FC 3d Cordless Premium all run the same 7.4V battery rail, share the same physical connector, and use the same BMS handshake to communicate charge state to the device. One battery fits all three variants.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the FC 3d Cordless platform. The BMS handshake initialised correctly, charge acceptance was normal, and the protection circuit tripped at the expected overcurrent threshold during a simulated blockage load.
• Dock charging discipline for the FC 3d series: Do not leave the vacuum sitting on the charging dock between uses. The FC 3d Cordless dock does not switch to a true standby state — it continues to trickle charge, which accelerates capacity fade in Li-ion cells. Charge to full, then remove the battery or device from the dock.

Suction dropping before the battery indicator reaches low

On the FC 3d Cordless, the suction motor is the highest current draw in the system. When the filter is partially blocked, the motor works harder and pulls more current than the BMS expects at a given charge level. Voltage sags under that load, and the device reads the sag as a low-battery condition even though the cell still has usable charge. Clean or replace the filter first — this resolves the symptom in most cases without a battery swap. If suction still drops after a clean filter, measure resting cell voltage: a healthy cell at 50% charge should sit above 7.2V.

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

This is a BMS overcurrent trip, not a depleted battery. It happens when sustained restricted airflow forces the motor to draw current above the protection circuit's threshold — the BMS cuts power to protect the cell, then resets once current demand drops. The pause before recovery is the BMS re-initialising. Check the filter and the floor nozzle for blockages before assuming the battery is faulty. If the cutout persists after clearing any blockage, the original cell's BMS threshold may have drifted — a replacement cell with a fresh BMS will restore the correct trip point.