About this replacement
Bomann AKS960CB — 3.6V Ni-MH Replacement Battery (5690)
This is a 3.6V, 2000mAh Ni-MH replacement battery for the Bomann AKS960CB cordless vacuum cleaner. It replaces OEM part number 5690. Fit this battery when the original cells no longer hold enough charge to complete a cleaning session.
- AKS960CB cell match: The AKS960CB runs a single 3.6V Ni-MH cell pack. The motor controller on this vacuum is tuned to the voltage curve and internal resistance of Ni-MH chemistry — swapping to a different chemistry would cause incorrect charge termination and erratic motor speed.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the AKS960CB platform. The BMS accepted the cell without fault codes, and the motor drew within expected current limits across both hard floor and carpet load profiles.
- Dock charging behaviour on this vacuum: Leave the AKS960CB on its charging dock continuously and the trickle current will degrade cell capacity within a few months. Charge the vacuum fully, then remove it from the dock. Reconnect only when the battery is substantially depleted.
Suction dropping before the battery indicator reaches low
This happens when the motor draws more current than the cell can sustain at rated voltage. A partially blocked filter is the most common trigger — restricted airflow forces the motor to work harder, pulling the cell voltage down early. The vacuum still shows charge remaining because the indicator reads resting voltage, not load voltage. Clean or replace the filter first, then assess whether the battery itself has degraded.
Motor cutting out mid-clean and recovering after a short pause
This is an overcurrent trip from the BMS, not a dead battery. When suction is restricted — blocked nozzle, clogged filter, or a rug caught against the intake — the motor stalls briefly and current spikes past the BMS threshold. The BMS cuts power to protect the cell, then resets after the cell cools and voltage recovers. Clear the blockage, confirm the filter is clean, and restart. If the cutout continues on a clear vacuum with a new battery, check that the cell contacts seat fully — a loose contact raises resistance and triggers the same trip at lower current.