About this replacement
Dreame X40 Master / RLX73CE — 14.4V Li-ion Replacement Battery (R2416-4S2P-XDEV)
This is a 14.4V, 6700mAh Li-ion battery pack for the Dreame X40 Master and RLX73CE cordless stick vacuums. It replaces OEM part R2416-4S2P-XDEV and restores motor power to both models. Capacity is rated at 96.48Wh.
- X40 Master and RLX73CE compatibility: Both models run on the same 14.4V battery rail with the same connector and BMS handshake protocol. One battery pack covers either unit — no adapter or firmware difference between them.
- Bench tested on actual hardware: We ran this pack through full charge and discharge cycles on the X40 Master platform. The BMS communicated correctly with the charger, held cutoff voltage at the expected low threshold, and triggered protection cleanly under a simulated motor-stall load.
- Dock charging habit on stick vacuums: Do not leave the X40 Master sitting on its charging dock permanently. Continuous dock charging applies a low-level trickle current that accelerates capacity fade in Li-ion cells over weeks. Charge fully, then remove the vacuum from the dock until the next use.
Suction dropping before the battery indicator reaches low
The X40 Master's motor draws significantly more current when airflow is restricted — a partially blocked filter or obstructed brush roll causes voltage to sag under load even when the cells still hold charge. The BMS reads this sag as a near-depleted state and throttles motor output before the indicator reflects the actual cell level. Cleaning the filter and clearing the brush roll resolves this in most cases. If suction still drops early after cleaning, check resting cell voltage — a healthy pack should read above 15.8V off the charger.
Motor cuts out mid-use then recovers after a short pause
This is a BMS overcurrent trip, not a failed battery. When the brush roll snags on thick carpet or debris, motor current spikes sharply and the BMS opens the discharge circuit to protect the cells. The unit powers off, and after a few seconds the BMS resets and allows restart. Clear the obstruction before switching the vacuum back on — restarting under the same load will trip the BMS again immediately. If trips occur on bare floors with no visible blockage, inspect the filter, as airflow restriction produces the same overcurrent spike.