About this replacement
Philips FC8794 / FC8792 Series — 10.8V Li-ion Replacement Battery (IP797)
This 10.8V, 2600mAh Li-ion battery replaces the IP797 (OEM ref 4322 005 38072) in Philips cordless stick vacuums. It fits the FC8794, FC8792, FC8007/01, and FC8007/81 among others. Voltage and cell count match the original pack exactly.
- FC8794 / FC8792 platform fit: These models share the same 10.8V three-cell Li-ion architecture, connector pinout, and BMS handshake protocol. A replacement that clears the BMS handshake on one will clear it on both — the charging circuit reads the same cell signature across the range.
- Bench tested on actual hardware: We ran this pack on the FC8794 chassis under full suction load. The BMS held steady through repeated motor-start current spikes and did not trip on sustained draw at rated airflow. Charge acceptance from the OEM dock completed without fault codes.
- Dock charging practice for cordless vacuums: Do not leave the vacuum sitting on the charging dock permanently. Cordless vacuums kept on continuous dock charge develop capacity fade significantly faster than those charged only when the pack is depleted. Charge to full, then remove from the dock.
Suction dropping before the battery indicator reaches low
This is one of the most common complaints on the FC8794, and most buyers blame the battery first. The actual cause is usually voltage sag under motor load — when the filter is partially blocked, the motor draws more current than rated, pulling cell voltage down faster than the indicator circuit registers. The indicator reads open-circuit or resting voltage, not loaded voltage, so it lags the real state of the pack. Clean the filter first, then retest suction at full charge before concluding the battery is at fault.
Motor cutting out mid-clean and recovering after a few seconds
This is a BMS overcurrent trip, not a failed battery. When suction is restricted — blocked filter, jammed brush roll, or a tight corner causing back-pressure — the motor stalls briefly and pulls a current spike above the BMS threshold. The BMS disconnects the pack to protect the cells, then resets once current drops. The fix is to clear the restriction: check the filter, brush roll, and intake path. If the cut-out stops after clearing the blockage, the pack is functioning correctly.