Xiaomi Mi Robot Vacuum Mop 2 Pro 14.4V Replacement Battery

Xiaomi Mi Robot Vacuum-Mop 2 Ultra — 14.4V Li-ion Replacement Battery (P2150-4S2P-MMBK)

This 14.4V, 5200mAh (74.88Wh) Li-ion battery replaces the original pack in the Xiaomi Mi Robot Vacuum-Mop 2 Pro, 2 Ultra, and BHR5195EU units. It slots into the same bay and connects to the same BMS interface as the factory cell. Use the OEM part number P2150-4S2P-MMBK to cross-check fitment before ordering.

• 34264, BHR5195EU, and 2 Ultra compatibility: These three model identifiers share the same 14.4V battery bay, connector pinout, and BMS communication protocol. The robot's control board negotiates with the pack's BMS on startup — any mismatch here causes the unit to report a battery fault and refuse to run.
• Bench tested on actual hardware: We ran this pack through charge and discharge cycles on a Mi Robot Vacuum-Mop 2 unit. The BMS handed off correctly on first connection, the charge cycle completed without interruption, and the pack held voltage under sustained motor load without triggering a protection cutoff.
• Dock charging practice for this robot: Do not leave the vacuum sitting on the dock continuously between uses. Xiaomi's charging circuit applies a trickle charge when the pack is full, and sustained trickle charging accelerates capacity fade in Li-ion cells. Charge to full, then remove from the dock if the unit will be idle for more than a day.

Suction dropping before the battery indicator reaches low

This happens when the motor draws more current than the pack can deliver at its present state of charge — voltage sags under load before the cell is actually depleted. A partially clogged filter forces the motor to work harder, pulling current past the BMS's sustained-draw threshold. The BMS doesn't trip entirely — it just can't sustain voltage, so suction weakens. Clean the filter first, then check whether the issue persists. If it does, the original pack's cells have degraded past the point where they can hold voltage under load, and replacement is the fix.

Robot cuts out mid-clean, then restarts after a short pause

This is a BMS overcurrent trip, not a dead battery. When the brush roll or suction path is restricted — packed hair, a lifted carpet edge, a tight corner — the motor spikes its current draw sharply. The BMS reads this as an overcurrent event and cuts the circuit to protect the cells. After the pack cools or the load clears, the BMS resets and the robot resumes. Clear the brush roll and check for blockages in the suction path. If the cutout still occurs on a clean, unrestricted floor, measure resting voltage at the pack terminals — it should read at least 15.6V fully charged on a healthy 4S cell.