About this replacement
Concept VP4380 — 18.5V Li-ion Replacement Battery (42392243)
This 18.5V 2600mAh lithium-ion battery replaces the original Concept part number 42392243. It fits the Concept VP4380 cordless vacuum cleaner. Voltage and capacity match the factory specification exactly.
- VP4380 platform fit: The VP4380 runs an 18.5V motor rail with a specific BMS handshake tied to the 42392243 cell configuration. Swapping to a different voltage pack trips the protection circuit and the vacuum will not start. This cell matches that rail and communicates correctly with the charger.
- Bench tested on actual hardware: We cycled this pack through full charge and discharge on the VP4380 platform. The BMS held cutoff voltage correctly under sustained motor load, and the charger completed a full charge cycle without fault codes.
- Dock charging habit on the VP4380: Do not leave the VP4380 sitting on the charging dock continuously. Cordless vacuums on permanent dock charge develop capacity fade faster than those charged only when depleted. Charge to full, then remove the vacuum from the dock.
Suction dropping before the battery indicator reaches low
This happens when the motor draws more current than rated — usually because the filter is partially blocked. Higher draw causes voltage to sag at the cell level before the indicator circuit registers a low-battery state. The BMS reads a load-induced voltage drop, not true depletion, and the vacuum loses suction while the indicator still shows charge. Clear the filter and check the brush roll for hair wrap before assuming the battery is at fault.
Motor cutting out mid-clean and then recovering after a pause
This is a BMS overcurrent trip, not a dead battery. When sustained suction restriction forces the motor to pull above the BMS threshold, the protection circuit opens and cuts power. A short pause lets the BMS reset and the vacuum runs again. The fix is the filter — a clean filter drops motor current back below the trip threshold. If the fault repeats on a clean filter, measure resting pack voltage; it should sit above 18V after a full charge.