Yeedi K8 14.4V Replacement Battery 3400mAh Li-ion

Yeedi K8 / Vac 2 Pro / YDVN11 — 14.4V Li-ion 3400mAh Replacement Battery

This is a 14.4V lithium-ion replacement battery rated at 3400mAh (48.96Wh) for the Yeedi K8, Vac 2 Pro, and YDVN11 robotic vacuum cleaners. It slots directly into the battery compartment and communicates with the onboard BMS to enable normal operation. No OEM part number is published for this cell — compatibility is confirmed by voltage, capacity, and connector match across all three models.

• K8, Vac 2 Pro, and YDVN11 compatibility: All three models run the same 14.4V power rail and use an identical battery bay connector with the same BMS communication protocol. A single cell covers the full range — no model-specific firmware difference affects charging or discharge behaviour.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the K8 platform. The BMS accepted the handshake on first connection, charge termination triggered correctly at full voltage, and the protection circuit tripped as expected under a simulated overcurrent load.
• Dock charging discipline for robotic vacuums: Do not leave the K8 sitting on the dock permanently between cleans. Continuous trickle charge from the dock degrades cell capacity significantly faster than charging only when the battery is depleted. Charge to full, then remove from the dock if the vacuum will sit unused for more than a day or two.

Suction dropping before the battery indicator reaches low

This happens when the motor draws more current than the BMS allows under load — typically caused by a partially blocked filter or brush roll restriction, not a dead battery. The cell voltage sags under the extra draw, the BMS throttles output to protect the cells, and suction drops even though the indicator still shows charge remaining. Clean the filter and check the brush roll for hair wrap before concluding the battery is at fault. A fully cleared airpath restores the motor to its rated draw and eliminates the sag.

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

This is a BMS overcurrent trip, not a flat battery. When the vacuum hits sustained resistance — dense carpet, a partial blockage, or a clogged filter — current draw spikes above the protection threshold and the BMS cuts power to the motor. After a few seconds the BMS resets, the motor restarts, and the cycle repeats. The fix is to clear the restriction: remove the filter, tap it clean, and check the inlet port for debris. Once airflow is restored, the motor returns to normal draw and the BMS stops tripping.