Kyvol Flutevac V20 Replacement Battery 21.6V 2500mAh

Kyvol Flutevac V20 Vacuum Cleaner — 21.6V Li-ion Replacement Battery (6INR19/65)

This is a 21.6V, 2500mAh Li-ion replacement battery for the Kyvol Flutevac V20 cordless stick vacuum. It slots directly into the Flutevac V20 battery compartment and restores full motor voltage to the cleaning unit. Capacity is 54Wh, matching the original cell configuration.

• Flutevac V20 fit: The V20 platform runs a 6-cell inline Li-ion pack at 21.6V nominal. The BMS on this unit monitors cell balance and cutoff voltage — a replacement must match that exact voltage rail and cell count or the vacuum will not power on.
• Bench tested on actual hardware: We ran this battery through charge cycles on the V20 platform and confirmed the BMS handshake, charge acceptance, and motor cutoff behaviour under simulated load. The pack held stable voltage across the draw range of the V20 motor.
• Dock charging behaviour on the V20: The Flutevac V20 charging dock does not stop trickle charging when the pack is full. Remove the vacuum from the dock once the indicator shows fully charged. Leaving it docked continuously accelerates capacity fade in Li-ion cells faster than normal cycle use.

Suction dropping before the battery indicator reaches low on the V20

This happens when the motor is drawing more current than rated — usually because a partially blocked filter forces the motor to work harder. Under that sustained high draw, cell voltage sags early and the BMS interprets it as a low-charge condition even when capacity remains. Clean or replace the V20 filter first before assuming the battery is at fault. If suction stabilises after a filter clean, the pack is not the issue.

V20 motor cuts out mid-clean and then recovers after a short pause

This is a BMS overcurrent trip, not a dead battery. When suction is restricted — blocked nozzle, clogged filter, or hair wrap on the brush roll — the motor current spikes above the BMS trip threshold and the pack shuts off to protect the cells. The BMS resets after a short cooldown, which is why power returns. Clear the blockage, check the filter, then restart. If the cutout repeats on a clear airpath, check that cell voltage at rest is above 21V before assuming a faulty pack.