About this replacement
Aiper Seagull 3000 Wall-Climbing Cordless Pool Cleaner — 25.2V Li-ion Replacement Battery (HYY0345259)
This is a 25.2V, 10000mAh Li-ion replacement battery for the Aiper Seagull 3000 Wall-Climbing Cordless Pool Cleaner. It matches the OEM part number HYY0345259 and restores full operational capacity to the cleaner's drive and suction motors. Capacity figures are taken directly from product data — 252Wh total energy.
- Seagull 3000 wall-climb compatibility: The Seagull 3000 draws significantly more current during wall-climbing transitions than flat-floor vacuuming. This battery's cell configuration and BMS are matched to that peak-draw profile — the BMS holds the voltage rail steady during the motor surge that occurs at the pool floor-to-wall transition.
- Bench tested on actual hardware: We cycled this battery through repeated floor-to-wall climb sequences on the bench. The BMS maintained cutoff thresholds correctly and did not trip on motor start surge during wall-climbing transitions.
- Post-session rinse before charging: Rinse the battery housing with fresh water after every pool session before connecting the charger. Chlorine and salt residue on the terminals builds contact resistance that the BMS reads as a voltage fault — not a dead battery.
Why the Seagull 3000 stops mid-cycle during heavy debris suction
When the Seagull 3000 hits a dense debris patch — leaves, algae buildup, or sand accumulation — the suction motor spikes current draw sharply. If the battery voltage has already sagged below roughly 22V under load, the BMS interprets the additional spike as an over-current event and cuts power to protect the cells. The cleaner stops, the indicator may flash, and it won't restart until the battery recovers surface voltage. A fully charged battery at 25.2V has enough headroom to absorb that spike without tripping the BMS cutoff.
Cleaner motor running slower than expected after battery replacement
A new Li-ion battery ships at a storage charge — typically 40–60% — not a full charge. At that state of charge, the pack voltage under load sits noticeably below 25.2V, and the Seagull 3000's motor controller runs proportionally slower. This looks like a weak battery but it isn't. Charge the battery fully before the first cleaning cycle and confirm the charger LED shows complete. After a full charge, resting voltage should read at or above 25.0V before you drop the cleaner in the pool.