Shark XB617U Replacement Battery 8.4V 3000mAh

Shark XB617U — 8.4V Ni-MH 3000mAh Replacement Battery (XB617U)

This is an 8.4V Ni-MH replacement battery rated at 3000mAh (25.2Wh) for the Shark XB617U cordless stick vacuum. It slots into the original battery housing and connects to the same charging circuit. Replace this pack when the original no longer holds a charge or suction drops off quickly into a cleaning session.

• XB617U platform fit: The XB617U battery pack uses a fixed 8.4V Ni-MH cell configuration matched to the vacuum's motor driver and charge controller. Swapping to a pack with the same cell count and connector keeps the charging circuit within its designed voltage window.
• Bench tested on actual hardware: We ran this pack through full charge and discharge cycles on the XB617U platform. The BMS handled sustained motor draw without triggering overcurrent cutoff, and the pack reached rated capacity within the first two cycles.
• Dock charging behaviour on the XB617U: Do not leave the vacuum permanently on the charging dock. Ni-MH cells in continuous trickle charge accumulate heat and lose capacity faster than cells charged only when depleted. Charge to full, then remove from the dock.

Cordless vacuum losing suction before the battery indicator reaches low

This happens when the motor draws more current than the battery can supply cleanly at its current state of charge. A partially blocked filter is the most common trigger — restricted airflow forces the motor to work harder, pulling current spikes that sag the pack voltage early. The vacuum's motor controller reads that voltage sag as a low-battery condition and reduces power before the indicator catches up. Clean or replace the filter first, then retest suction across a full charge cycle.

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

This is a BMS overcurrent trip, not a dead battery. When sustained suction restriction spikes current draw beyond the pack's rated threshold, the BMS shuts the output to protect the cells — then resets once temperature and current drop. The fix is almost always a blocked filter or a clog in the brush roll housing forcing the motor to stall. Clear the restriction, confirm the filter is clean, and the cutout behaviour stops. If it continues on an unblocked vacuum, check the pack voltage under load — it should hold above 7.0V during normal motor operation.