AEG 900273786 Cordless Vacuum Replacement Battery 10.8V 1500mAh

AEG 900273786 / AG3101 Series — 10.8V Li-ion Replacement Battery

This is a 10.8V 1500mAh Li-ion battery for AEG cordless vacuum cleaners including the 900273786, AG3101, 900273793, and 900273794 models. It slots into the same housing as the original and connects to the same BMS communication line the charger expects. Capacity is 1500mAh (16.2Wh), matching the factory spec.

• AG3101 and 900273xxx platform compatibility: These models share the same 10.8V battery rail, connector pinout, and BMS handshake protocol. A battery that works on one works across the group — the charger reads the same authentication signal from each unit.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on an AEG-compatible dock. The BMS held cutoff at the correct low-voltage threshold and allowed full recharge without a handshake error or charge-refusal event.
• Dock behaviour after replacement: Do not leave this vacuum on the charging dock continuously. AEG cordless vacuums on permanent dock charge suffer faster capacity fade than units charged only when depleted. Charge to full, then remove from the dock.

Suction dropping before the battery indicator reaches low

This is a voltage sag issue, not a capacity issue. When the motor encounters resistance — a partially blocked filter, a heavy carpet pile, or a debris jam — it draws more current than the rated load. The cell voltage dips below the motor controller's operating threshold before the battery gauge registers empty. The vacuum loses suction but the indicator still shows charge remaining. Clean the filter first; a restricted airflow path forces the motor to work harder and amplifies the sag.

Motor cuts out mid-use then recovers after a short pause

This is the BMS tripping on an overcurrent event, not a faulty battery. Sustained restricted suction — from a clogged filter or blocked nozzle — pushes motor current above the BMS protection threshold. The BMS disconnects the cell to prevent damage, which looks like the vacuum switching itself off. After a brief pause the BMS resets and the vacuum starts again. Check the filter and nozzle for blockage before assuming the battery is at fault; if the issue persists after clearing the restriction, measure resting cell voltage — it should sit above 11.0V after a full charge.