About this replacement
VBOT M235 / M8 / My Mini Robot — 14.4V Ni-MH Replacement Battery (B2312777)
This is a 14.4V, 1500mAh Ni-MH replacement battery pack for the VBOT M235, M8, and My Mini Robot robotic vacuum cleaners. It replaces OEM part number B2312777 when the original cell has degraded or failed. Fit the correct voltage and chemistry before ordering — Ni-MH and Li-ion packs for robotic vacuums are not interchangeable.
- M235, M8, and My Mini Robot compatibility: These three models share the same 14.4V power rail, physical connector, and BMS communication profile, which is why a single pack covers all three. Swapping between them does not require any firmware or hardware change.
- Bench tested on actual hardware: We ran this pack through charge and discharge cycles on the M235 platform. The BMS held cutoff correctly at the low-voltage threshold and accepted a full charge without thermal event or charge-rejection flags.
- Dock charging on robotic vacuums: Do not leave this vacuum sitting on the dock permanently. Ni-MH cells on continuous trickle charge develop capacity fade faster than cells charged only when depleted. Charge to full, then remove the unit from the dock until the next cleaning session.
Suction dropping before the battery indicator reaches low
Ni-MH cells show voltage sag under load before the pack is genuinely depleted. On the M235, the motor draws higher current when the filter is partially blocked or the brush roll is restricted. That load spike pulls cell voltage down faster than the indicator circuit expects, so the vacuum appears to run out of power while the indicator still shows charge. Clean the filter and clear any brush roll debris first — if suction recovers and runtime improves, the battery is not the cause.
Motor cuts out mid-cycle and then recovers after a short pause
This is a BMS overcurrent trip, not a dead battery. When the motor encounters sustained restriction — a blocked filter, tangled brush roll, or thick rug edge — current draw spikes past the BMS threshold and the pack disconnects to protect the cells. The BMS resets after a short cool-down, which is why the vacuum restarts on its own. Clear the restriction, check that the filter is seated correctly, and test again. If the trip repeats on a clean, unobstructed floor, measure pack voltage under load — a healthy 14.4V Ni-MH pack should hold above 12V during normal motor operation.