Xiaomi Mi Scooter 3 14.4V Replacement Battery BHR8629EU

Xiaomi Robot Vacuum S20 / BHR8629EU — 14.4V Li-ion Replacement Battery (P2332-4S1P-SCEV)

This 14.4V 3400mAh (48.96Wh) Li-ion battery pack replaces the OEM unit in the Xiaomi Robot Vacuum S20 and BHR8629EU. It fits directly into the D106 platform shared across that model range. Voltage and cell count match the original BMS handshake requirements.

• S20 / D106 platform compatibility: The BHR8629EU and Robot Vacuum S20 share the D106 chassis and a 4S1P cell configuration running a 14.4V nominal rail. This replacement matches that configuration — same cell count, same connector pinout, same BMS communication protocol.
• Bench tested on actual hardware: We ran this pack through charge and discharge cycles on the D106 platform. The BMS accepted the handshake without fault codes, and the protection circuits responded correctly to overcurrent and over-discharge thresholds.
• Dock charging behaviour on the S20: The Xiaomi S20 returns to its dock automatically after each clean. Do not leave the unit docked continuously between uses — the dock maintains a trickle charge that accelerates capacity fade in Li-ion 4S packs. Charge to full, then remove the robot from the dock until its next scheduled run.

Suction dropping mid-clean on the S20 before the battery indicator shows low

The S20's motor draws a surge current when it hits a transition from hard floor to carpet or encounters a partial blockage. If the battery pack has degraded internal resistance, it cannot sustain that surge without voltage sag — the motor controller throttles fan speed before the battery indicator registers low. This is a cell condition issue, not a sensor fault. A fresh pack with low internal resistance holds the voltage rail steady through those transient load spikes.

Robot Vacuum S20 motor cuts out and then recovers during a cleaning cycle

This is a BMS overcurrent trip, not a motor fault. When the side brush or suction inlet is partially blocked, the fan motor pulls sustained current above the BMS protection threshold — the pack disconnects briefly to protect the cells, then resets. The fix is to clear the brush roll and inlet, then check the filter. A clogged filter forces the motor to work harder on every pass, keeping current draw elevated and triggering repeat trips. Inspect and clean the filter before fitting a replacement battery — if the restriction stays, the new pack will trip on the same cycle.