Electrolux ErgoRapido Compatible Battery 4.8V 2000mAh

Electrolux ErgoRapido / Rapido — 4.8V Ni-MH Replacement Battery (405 52 51-53/4)

This is a 4.8V, 2000mAh Ni-MH replacement battery for the Electrolux ErgoRapido and Rapido cordless stick vacuums. It replaces OEM part 405 52 51-53/4 and restores power to the handheld motor unit. Capacity is 2000mAh (9.6Wh), matching the original specification.

• ErgoRapido and Rapido compatibility: Both models run the same 4.8V cell pack with an identical connector and motor voltage rail. No wiring changes or adapters needed — the BMS footprint is the same across both variants.
• Bench tested on actual hardware: We cycled this cell through motor start and sustained suction loads. The BMS held steady under continuous draw and did not trip during repeated start sequences on a restricted inlet.
• Dock charging discipline: Do not leave the vacuum sitting on the charging dock after it reaches full charge. Ni-MH cells in continuous trickle charge develop capacity fade faster than cells charged only when depleted. Charge to full, then remove from the dock.

Suction dropping before the battery indicator reaches low

The ErgoRapido's motor draws harder when the filter is partially blocked, pulling current above the rated draw before the cell is actually depleted. The battery indicator reads the cell voltage, not the motor load — so it can show half-charge while the motor is already starving. Clean or replace the filter first. If suction recovers, the cell is fine; if it doesn't, check cell voltage under load — it should hold above 4.2V during normal operation.

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

This is a BMS overcurrent trip, not a dead battery. It happens when sustained restricted airflow forces the motor to draw more current than the protection circuit allows. The BMS shuts the output, then resets once temperature or current drops. Clear the brush roll, check the post-filter behind the motor, and confirm the inlet path is unobstructed. If the trip keeps recurring after clearing blockages, the cell's internal resistance may have risen enough that motor-start spikes now exceed the trip threshold.