Electrolux PF91 Replacement Battery 32.4V 2000mAh Li-ion

Electrolux PF91 Series — 32.4V Li-ion Replacement Battery (56645709099)

This is a 32.4V 2000mAh lithium-ion battery pack for the Electrolux PF91 and PF91-ALRP cordless stick vacuum. It replaces OEM part 56645709099 when the original cell degrades and can no longer hold charge. Voltage and connector match the original factory spec.

• PF91 and PF91-ALRP fit: Both models run the same 32.4V power rail, share the same battery bay connector, and use the same BMS handshake. One battery covers both variants without modification.
• Bench tested on actual hardware: We ran the pack through full charge and discharge cycles on a PF91 platform. The BMS responded correctly to charge termination, over-discharge cutoff, and motor-start current draw without tripping protection prematurely.
• Dock charging behaviour on the PF91: Do not leave the vacuum sitting on the charging dock between uses. Continuous dock contact keeps the BMS cycling trickle charge into the cells, which accelerates capacity fade. Charge fully, then remove from the dock.

Suction dropping before the battery indicator reaches low

This is one of the most misread symptoms on the PF91. The motor draws harder when the filter is partially blocked, pulling more current than the cell is rated to deliver continuously. Voltage sags under that load before the state-of-charge indicator registers a low battery. The fix is not a new battery — clean or replace the filter first, then retest. If suction recovers, the battery was not the fault.

Motor cutting out mid-run then restarting after a short pause

This pattern is a BMS overcurrent trip, not a dead cell. Sustained restricted airflow forces the motor to draw current above the BMS protection threshold, and the pack shuts the output to protect the cells. It resets after a few seconds once current demand drops. Clear the filter and check the nozzle for blockages before assuming the battery is faulty. If the cutout persists on a clean, unobstructed run, measure pack voltage under load — a healthy cell holds above 28V at the terminals during operation.