Concept VP4320 7.2V Cordless Vacuum Replacement Battery 1800mAh

Concept VP4320 — 7.2V Ni-MH Replacement Battery (42391659)

This is a 7.2V, 1800mAh Ni-MH replacement battery for the Concept VP4320 cordless handheld vacuum cleaner. It matches the OEM part number 42391659 and slots directly into the VP4320 battery compartment. Voltage, capacity, and connector position match the original specification.

• VP4320 compatibility: The VP4320 runs a single 7.2V Ni-MH pack that powers the motor controller directly — no cell-count variation exists in this model family, so the voltage rail and connector type are fixed across all VP4320 units.
• Bench tested on actual hardware: We cycled this pack through discharge under a simulated motor load and confirmed the BMS held the voltage rail stable until the protection cutoff, with no premature shutdown or false low-battery flags.
• Dock charging on the VP4320: Do not leave the VP4320 sitting on the charging dock permanently. Continuous trickle charge accelerates capacity fade in Ni-MH cells faster than in lithium packs. Charge to full, then remove the unit from the dock.

Suction dropping before the battery indicator reaches low

The VP4320 motor draws more current when the filter is partially blocked — the battery has to supply more amps to maintain the same airflow speed. Under that sustained high draw, Ni-MH cells show a voltage sag that the motor controller reads as insufficient power, and suction drops noticeably before the indicator registers low. This is not always a failing battery. Check the filter first — if suction recovers after cleaning the filter, the cell pack is fine. If suction still sags on a clean filter, the cells have degraded below 6.8V under load and replacement is needed.

Motor cutting out mid-use and then recovering after a short pause

This pattern points to an overcurrent trip in the battery protection circuit. It happens when restricted airflow — blocked filter, clogged nozzle, or tight carpet pile — forces the motor to pull current above the BMS threshold. The BMS cuts power to protect the cells, then resets after a brief rest as internal temperature drops. Clearing the blockage is the first step. If the cutout continues on an unobstructed surface, the cells can no longer sustain the required current without tripping the BMS, and the pack needs replacing.