About this replacement
Philips Aqua Plus 8000 — 25.2V Li-ion Replacement Battery (D116-7S1P)
This is a 25.2V 3900mAh Li-ion replacement battery for the Philips Aqua Plus 8000 cordless wet and dry vacuum cleaner. It fits model numbers XC8349/01, XC8349/01R1, and XC8057/01, among others. The OEM part number is D116-7S1P — confirm this against your original battery before ordering.
- Aqua Plus 8000 series compatibility: These models share the same 25.2V seven-cell architecture, connector pinout, and BMS communication protocol. A battery built to this spec slots into any of them without adapter or modification.
- Bench tested on actual hardware: We ran this cell pack through charge and discharge cycles on the Aqua Plus 8000 platform. The BMS handshake completed correctly, charge acceptance was normal, and the motor controller received clean voltage through both wet and dry suction loads.
- Dock charging habit for this vacuum: Do not leave the Aqua Plus 8000 sitting on its charging dock permanently. Cordless vacuums on continuous dock charge develop capacity fade significantly faster than units charged only when the battery is depleted. Charge to full, then remove from the dock.
Motor cutting out under heavy carpet load on the Aqua Plus 8000
The Aqua Plus 8000 motor draws a spike of current when suction is restricted — thick carpet, a partially blocked filter, or a clogged brush roll all trigger this. The BMS reads that overcurrent spike as a fault condition and trips the circuit to protect the cells. Power returns after a few seconds once the BMS resets. If this happens repeatedly, check the filter and brush roll before assuming the battery is faulty — a clean airpath brings motor draw back within the BMS threshold.
Suction dropping noticeably before the battery indicator reaches low
This is voltage sag under load, not a low state-of-charge. As Li-ion cells age or a filter partially blocks airflow, the motor pulls harder to maintain suction, dragging the voltage down faster than the indicator tracks it. The result is weak suction while the display still shows two or three bars. Replacing a worn cell pack restores the voltage headroom the motor needs — but clean the filter first to confirm the new battery is not immediately fighting the same restriction. A healthy pack on a clean filter holds voltage above 22V through a full cleaning run.