Airzeen G20 Pro Cordless Vacuum Compatible Battery 12.8V 4000mAh

Airzeen G20 Pro — 12.8V LiFePO4 Replacement Battery

This is a 12.8V, 4000mAh LiFePO4 replacement battery for the Airzeen G20 Pro cordless stick vacuum. It slots into the original battery position and restores power to the vacuum's motor and suction system. Capacity matches the product specification at 51.2Wh.

• G20 Pro motor rail compatibility: The G20 Pro runs its brushless motor on a 12.8V nominal rail. LiFePO4 holds that voltage flat across most of the discharge curve, which keeps suction consistent longer than older lithium-ion packs that sag early under motor load.
• Bench tested on actual hardware: We cycled this pack through full charge and discharge on the G20 Pro motor circuit. The BMS handled the motor's start-up current spike without tripping, and cell temperature stayed within normal operating range across the full discharge.
• Dock charging on the G20 Pro: Do not leave the G20 Pro sitting on the charging dock permanently. LiFePO4 cells in continuous trickle charge develop capacity fade faster than cells charged only when depleted. Charge to full, then remove the vacuum from the dock.

Suction dropping before the battery indicator reaches low on the G20 Pro

When the G20 Pro filter is partially blocked, the motor has to work harder to pull the same airflow. That increases current draw beyond what the battery and motor circuit expect at normal load. The BMS reads this as abnormal demand and reduces output current to protect the cells, which the user feels as a drop in suction. Check and clean the filter first — if suction recovers immediately, the battery was not the cause.

G20 Pro motor cutting out mid-use and recovering after a few seconds

This is a BMS overcurrent trip. It happens when the motor pulls a sustained high current — typically during a blockage or when running across thick carpet with a restricted filter. The BMS shuts the output, the motor stops, and after a short reset window it allows current to flow again. Clear any blockage, clean the filter, then restart the vacuum. If cut-outs continue on a clear machine, check that the battery terminal voltage under load stays above 10.0V.