Shark XBT800 Replacement Battery 10.8V 3000mAh Ni-MH

Shark SV800 / VX63 Series — 10.8V Ni-MH Replacement Battery (XBT800)

This is a 10.8V, 3000mAh Ni-MH battery pack for the Shark SV800, SV800C, and VX63 cordless stick vacuums. It replaces OEM part numbers XBT800 and XSB800CH. When the original pack can no longer hold a useful charge, this swap restores full operating voltage to the motor.

• SV800 and VX63 platform fit: Both models run the same 10.8V motor rail and use the same battery housing and connector arrangement, which is why one pack covers the full range. The BMS on each unit monitors cell voltage and will cut the motor if pack voltage drops below the lower threshold mid-cycle.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on an SV800 chassis. The BMS accepted the cell group without errors, charge termination triggered correctly at full capacity, and the motor drew rated current without tripping overcurrent protection under sustained load.
• Dock charging habit on the SV800: Leaving the SV800 on its charging dock continuously after the pack reaches full charge accelerates capacity fade in Ni-MH cells. Charge the unit fully, then remove it from the dock. Only return it to charge when the pack is meaningfully depleted.

Cordless vacuum losing suction before the battery indicator reaches low

This happens when internal cell resistance has risen enough that the pack can no longer sustain the current the motor demands under load — even though the indicator still shows charge remaining. Voltage at the motor terminals sags under draw, reducing fan speed and suction noticeably. A blocked or dirty filter compounds this: the motor works harder against the restriction, pulling more current and accelerating the voltage sag. Replacing the pack eliminates the cell-resistance issue; clean the filter at the same time to keep motor draw within rated spec.

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

This is a BMS overcurrent trip, not a motor fault. When suction is restricted — by a clogged filter or a blockage in the hose — the motor draws current above the BMS protection threshold, and the BMS disconnects the pack to protect the cells. After a brief pause, the BMS resets and allows the motor to restart. Clearing the blockage and cleaning the filter is the fix. If the trip happens immediately on a clean machine with a new pack, check that the filter is fully seated — a dislodged filter collapses airflow instantly and triggers the same overcurrent event.