About this replacement
Water Tech Pool Blaster Pro Series — 11.1V Li-ion Replacement Battery (LB003S2P-C)
This is an 11.1V, 5200mAh Li-ion replacement battery for the Water Tech Pool Blaster Pro, Precision Li, and Pro 900 cordless pool vacuums. It replaces part number LB003S2P-C and fits directly into the battery compartment on all three models. Use it when your original battery no longer holds charge or cuts out mid-clean.
- Pool Blaster Pro, Precision Li, Pro 900 compatibility: All three models run the same 11.1V three-cell Li-ion architecture and use the same BMS handshake with the charger. A single battery part covers the full range with no modifications needed.
- Bench tested on actual hardware: We ran this cell through full charge and discharge cycles on a Pool Blaster Pro unit. The BMS responded correctly to charge termination, and the motor drew consistently within the rated current envelope across suction modes.
- Pool vacuum charging protocol: Do not leave the Pool Blaster on the dock continuously between uses. These vacuums see irregular charge cycles — a session every few days with long dock time in between. Trickle current during extended dock sitting degrades cell capacity faster than regular discharge cycles do. Charge to full, then remove from the dock.
Suction dropping before the battery indicator hits low
This is a motor voltage sag issue, not a capacity issue. When the filter is partially blocked, the motor works harder, pulls more current, and causes the battery voltage to sag under load — even when the cell still has significant charge remaining. The BMS reads this sag as a low-voltage condition and scales back power delivery. Clean or replace the filter first; if suction restores immediately, the battery is fine.
Motor cutting out mid-clean then recovering after a pause
This is a BMS overcurrent trip, not a motor fault. Sustained restricted suction — from a clogged filter or blocked intake — causes the motor to draw current above the BMS trip threshold. The BMS cuts power to protect the cells, then resets after a short thermal recovery window. Clear the intake and rinse the filter before assuming the battery is at fault. If the cutout stops after cleaning, the battery is operating exactly as it should.