Gtech AirRam MK2 Compatible Battery 22.2V 2500mAh

Gtech AirRam MK2 Series — 22.2V Li-ion Replacement Battery (103A105)

This 22.2V 2500mAh lithium-ion battery replaces part number 103A105 in the Gtech AirRam MK2 cordless stick vacuum. It fits the AirRam MK2, AirRam MK2 K9, AR20, and AR21 models. Capacity is 55.5Wh — matched to the original specification in the product data.

• AirRam MK2 and K9 compatibility: The MK2, MK2 K9, AR20, and AR21 share the same 22.2V cell configuration, connector pinout, and BMS communication protocol — which is why one battery covers all four variants without modification.
• Bench tested on actual hardware: We ran this battery through full charge and discharge cycles on the AirRam MK2 platform. The BMS correctly reported cell state to the vacuum's charge indicator, and the motor spun up without triggering overcurrent cutoff under normal floor load.
• Dock charging habit on the AirRam MK2: Do not leave the vacuum sitting on the charging dock permanently. The AirRam MK2 dock does not cut trickle current after the battery reaches full charge, so continuous docking accelerates capacity fade. Charge to full, then remove it from the dock.

Suction dropping before the battery indicator reaches low

On the AirRam MK2, suction loss often happens well before the battery LED shows a low charge warning. The motor draws more current when the filter is partially blocked, which pulls the cell voltage down faster than the indicator circuit expects. The BMS reads this as normal discharge, so no warning fires. Check and clean the filter first — a restricted filter forces the motor into a sustained high-draw state that mimics a depleted battery.

Motor cuts out mid-clean then recovers after a pause

This is a BMS overcurrent trip, not a dead battery. When suction is restricted — by a blocked filter, a tangled brush bar, or a partial blockage — the motor draws a sustained current spike that exceeds the BMS threshold. The BMS shuts the output to protect the cells, then resets after a short cool-down. Clear any blockage and inspect the filter before assuming the battery is at fault. After clearing the restriction, confirm the pack is sitting above 20V before restarting.