About this replacement
Dreame H20 / H20 Pro / H20ce — 21.6V Li-ion Replacement Battery (W2420R)
This is a 21.6V Li-ion replacement battery for the Dreame H20, H20 Pro, and H20ce cordless stick vacuums. It carries a 4000mAh (86.4Wh) capacity and uses part number W2420R. Fits the battery bay on all three H20-series models with no modification required.
- H20, H20 Pro, and H20ce compatibility: All three models share the same 21.6V battery platform, connector pinout, and BMS handshake protocol — a single W2420R cell fits all three without any adapter or firmware change.
- Bench tested on actual hardware: We ran this cell through full charge and discharge cycles on an H20 Pro unit. The BMS negotiated correctly with the charger on first contact, and the cell held voltage under continuous motor load without triggering an overcurrent trip.
- Dock charging habit on the H20 series: The H20 charging dock supplies power continuously when the vacuum is seated. Leaving the vacuum docked permanently accelerates capacity fade in Li-ion cells. Charge fully, then remove the vacuum from the dock until the next use.
Suction dropping before the battery indicator reaches low on the H20
This happens when the motor draws more current than rated — usually caused by a partially blocked filter or restricted airflow path. Under that load, cell voltage sags early and the vacuum's power management circuit reduces motor speed before the fuel gauge registers low. The indicator reads remaining charge, not available voltage under load. Clean or replace the HEPA filter first; if suction recovers and holds, the battery is not the cause.
Motor cuts out briefly then restarts during sustained carpet cleaning
This is a BMS overcurrent trip, not a dead battery. When the H20 is pushed through thick carpet with a restricted filter, the motor draws a current spike that exceeds the BMS protection threshold. The BMS cuts output for two to three seconds, then resets. The fix is to clear the filter and check the brush roll for hair wrap before concluding the battery is faulty. If the trip only occurs on heavy carpet with a clean filter, verify the cell voltage reads at least 21.0V at rest before ruling out a weak cell.