About this replacement
Dreame H30 Ultra — 21.6V Li-ion Replacement Battery (W2439P-01-0D)
This is a 21.6V, 4600mAh Li-ion replacement battery for the Dreame H30 Ultra cordless stick vacuum. It slots into the H30 Ultra battery housing and powers the motor and onboard controls. OEM part numbers W2439P-01-0D and W2311-01 both apply to this unit.
- H30 Ultra platform fit: The H30 Ultra runs a 21.6V nominal rail with a BMS that monitors cell voltage and current draw during motor start. This replacement matches that voltage profile and connector pinout, so the vacuum's onboard controls recognise the pack without throwing a fault.
- Bench tested on actual hardware: We cycled this pack through full discharge and recharge sequences on the H30 Ultra platform, confirming the BMS handshake completes correctly and the vacuum transitions between power modes without triggering overcurrent protection on startup.
- Dock charging habit for this vacuum: Do not leave the H30 Ultra sitting on the charging dock permanently. Continuous trickle charging degrades cell capacity faster than normal use cycles. Charge to full, then remove from the dock until the battery is depleted.
Suction dropping before the battery indicator reaches low
This is a voltage sag issue, not always a failing battery. When the filter is partially blocked, the motor draws more current than rated to maintain suction — the cells sag under that load and the BMS may reduce output to protect them. The vacuum feels underpowered well before the indicator reads empty. Clean or replace the filter first, then retest. If sag persists on a clean filter, discharge the pack to around 21V and do a full recharge cycle to recalibrate.
Motor cuts out mid-clean then recovers after a few seconds
This is a BMS overcurrent trip, not a dead battery. It happens when sustained restricted airflow — blocked filter, blocked brush roll, or sealed nozzle — forces the motor to pull current above the BMS threshold. The BMS shuts the pack down momentarily, then resets once current demand drops. Clear the restriction and the cut-outs stop. If the motor cuts out even on an unrestricted vacuum, check that the battery contacts are clean and seated fully — a partial connection causes the same intermittent dropout.