Dreame H30 21.6V Replacement Battery W2420 4000mAh

Dreame H30 — 21.6V Li-ion Replacement Battery (W2420)

This is a 21.6V 4000mAh (86.4Wh) lithium-ion battery for the Dreame H30 cordless stick vacuum. It replaces OEM part W2420 and fits the H30 platform directly. When the original cell degrades and suction drops mid-clean, this is the replacement unit.

• H30 platform fit: The H30 uses a 21.6V nominal rail with a specific connector and BMS handshake. This cell matches that voltage rail and communicates with the H30's motor controller the same way the factory unit does — no modification needed.
• Bench tested on actual hardware: We cycled this battery through sustained high-suction loads and monitored BMS behaviour under voltage sag. The protection circuit held stable cutoff thresholds and recovered cleanly after load was removed.
• Dock charging habit on the H30: Do not leave the H30 sitting on its charging dock between uses. Cordless vacuums on continuous dock charge accumulate trickle-charge stress on the cells. Charge to full, then remove from the dock until the next clean.

Suction dropping before the battery indicator reaches low

The H30 motor draws significantly more current when airflow is restricted — a partially blocked filter is the most common trigger. Under that elevated draw, cell voltage sags early and the motor controller reads it as low battery before the indicator catches up. The result is weak suction with bars still showing on the display. Clean or replace the filter first; if suction restores, the battery was not the fault. If suction is still weak with a clean filter and a fresh charge, measure resting voltage — a healthy cell sits above 24V fully charged.

Motor cutting out and recovering mid-clean

This is a BMS overcurrent trip, not a dead battery. When the H30 runs sustained high-power mode against a blocked filter or dense carpet pile, current draw spikes past the protection circuit's threshold. The BMS cuts the motor to protect the cells, then resets once current demand drops. It can feel like an intermittent fault but the pattern is consistent — it happens under load, not at rest. Clear the filter, check the roller for tangled debris, and drop to standard suction mode on heavy carpet to stay below the trip threshold.