Liectroux C30B Replacement Battery 14.4V 3400mAh Li-ion

Liectroux C30B Series — 14.4V Li-ion Replacement Battery (MD-C30B)

This is a 14.4V 3400mAh Li-ion replacement battery for the Liectroux C30B robotic vacuum. It fits the C30B, C30B 2D, C30B 2D Wifi Robot Vacuum Cleaner, and E30 models. OEM part number MD-C30B. Capacity is 48.96Wh.

• C30B and E30 platform fit: These models share the same 14.4V power rail, battery bay dimensions, and BMS communication protocol. The MD-C30B part number covers all variants in this range — the connector pinout and housing are identical across C30B, C30B 2D, and E30 units.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on C30B hardware. The BMS handshake cleared without error, charge acceptance was normal from flat, and overcurrent protection tripped correctly under a simulated motor blockage before recovery.
• Dock charging discipline for the C30B: Liectroux robotic vacuums left on the dock continuously after reaching full charge develop capacity fade faster than those charged only when depleted. Once the indicator shows full, remove the unit from the dock. Return it when the battery is low.

Suction dropping before the battery indicator shows low on the C30B

This happens when cell voltage sags under motor load before the indicator threshold triggers. A degraded or partially discharged cell cannot sustain the 14.4V rail under the sustained draw of the suction motor — voltage drops, the motor slows, and suction weakens. The battery indicator reads state-of-charge at rest, not under load, so it can still show green while suction is already reduced. A replacement cell at full charge restores rail voltage under load; if suction still drops early, check the filter before assuming the battery is at fault.

Motor cuts out mid-clean and then recovers after a few seconds

This is a BMS overcurrent trip, not a battery failure. When the suction path is restricted — blocked brush roll, clogged filter, or debris caught at the inlet — the motor draws above its rated current to maintain speed. The BMS interprets this as a fault and cuts power to protect the cell. After a few seconds the protection resets and the motor restarts. Clean the filter and clear the brush roll first. If the trip repeats on a clean, unobstructed machine, verify battery voltage under load reads above 12.5V before suspecting the cell.