Xiaomi Mi Robot Vacuum Mop 2 Lite 14.4V Replacement Battery

Xiaomi Mi Robot Vacuum Mop 2 Lite — 14.4V Li-ion Replacement Battery (260V-4S1P)

This 14.4V, 2500mAh Li-ion battery replaces the original pack in the Xiaomi Mi Robot Vacuum Mop 2 Lite robotic vacuum cleaner. It fits models MJSTL, 042621, BHR5217EU, and related variants using OEM part numbers 260V-4S1P and N011-4S1P. Physical dimensions are 69.70 × 38.30 × 37.30mm — confirm these against your existing pack before ordering.

• MJSTL / BHR5217EU platform: These model numbers share the same 14.4V four-cell series configuration, connector pinout, and BMS communication protocol. A battery that handshakes correctly on one will function identically on the others without modification.
• Bench tested on actual hardware: We ran this pack through full charge and discharge cycles on the Mi Robot Vacuum Mop 2 Lite platform. The BMS negotiated correctly with the dock charger, voltage stayed stable through the cleaning cycle, and the low-battery return-to-dock signal fired at the expected threshold.
• Dock charging habit for this robot: Do not leave the vacuum sitting on the charging dock indefinitely between uses. The Mop 2 Lite applies a trickle charge whenever docked and powered. Charge the battery to full, then remove it from the dock or power the dock off — continuous low-current charging accelerates cell degradation faster than regular full cycles.

Suction dropping before the battery indicator reaches low

The Mop 2 Lite's motor draws significantly more current when the dustbin filter is partially blocked. Under that elevated load, the battery voltage sags early — the BMS reads this as a low-cell condition and begins throttling motor power before the indicator has moved to the low zone. The vacuum feels like it's losing suction, but the root cause is restricted airflow forcing an overcurrent draw, not a failing battery. Clean the filter and check the dustbin seal before concluding the battery is at fault.

Motor cuts out mid-clean and then recovers after a short pause

This is a BMS overcurrent trip, not a faulty motor or dead cell. When suction is restricted — blocked brush roll, full dustbin, or clogged filter — the motor draws current beyond the BMS trip threshold, and the BMS disconnects the pack to protect the cells. After a brief thermal or timer reset, the BMS re-engages and the vacuum runs again. Clear the blockage, check the filter for debris compaction, and restart the clean. If the trip repeats on an unobstructed clean, measure the pack voltage under load — it should hold above 12.5V at the terminals.