KONKA KCMY-2901-T Cordless Vacuum Replacement Battery 11.1V

KONKA KCMY-2901-T — 11.1V Li-ion Replacement Battery (ZL18650-B4-3S1P)

This is an 11.1V 2600mAh Li-ion battery pack for the KONKA KCMY-2901-T cordless stick vacuum. It replaces the original ZL18650-B4-3S1P pack when the existing cell has degraded or no longer holds a usable charge. Voltage and cell configuration match the original motor drive circuit.

• KCMY-2901-T motor rail compatibility: The KCMY-2901-T motor controller is tuned to an 11.1V nominal three-cell series pack. This replacement uses the same 3S1P cell arrangement, so the BMS communicates correctly with the vacuum's charge and discharge logic without modification.
• Bench tested on actual hardware: We ran this pack through charge cycles and a sustained draw test that simulates the KCMY-2901-T motor under carpet load. The BMS held the discharge curve steady and triggered cutoff cleanly at the low-voltage threshold — no premature trip, no voltage sag under normal operating draw.
• Dock charge discipline on the KCMY-2901-T: Do not leave this vacuum sitting on the charging dock indefinitely. The KCMY-2901-T dock delivers a continuous trickle once the pack is full, and Li-ion cells held at 100% state of charge under trickle current lose capacity significantly faster. Charge to full, then remove from the dock.

Cordless vacuum losing suction before the battery indicator reaches low

This happens when the motor is drawing more current than rated — usually because the filter is partially blocked. A restricted airflow path forces the motor to work harder, pulling the cell voltage down faster than a clean-filter run would. The BMS reads this elevated draw as a sign the pack is depleting and begins throttling output before the indicator catches up. Clean or replace the filter first, then retest — suction drop should shift back toward the end of the charge cycle where it belongs.

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

This is a BMS overcurrent trip, not a faulty battery. When suction is sustained against a blockage — debris caught at the nozzle, a clogged filter, or heavy carpet fibres — current spikes past the BMS protection threshold and the pack shuts the output circuit. After a brief cooldown, the BMS resets and the motor runs again. Clear the blockage, check the filter for buildup, and resume. If the trip repeats on a clear path, check that the replacement pack voltage reads at or above 10.8V under light load before assuming a cell fault.