Cordless or corded pool robot: what changes when the cable goes
Take the cable off a pool robot and its power, its reach and its way out of the water all have to come from somewhere else.
On this page3 sections
A corded pool robot comes out on its cable: you draw it to the side and lift it by the handle. A cordless one has nothing to pull. One tester, who says he has run more than 30 cleaners in his own pool, describes having to “wade in, grab the handle, and haul a waterlogged, 25-pound machine out” after each session.
Maytronics, which makes the Dolphin robots, sells both kinds on its US store. The corded Dolphin Nautilus CC Plus costs $749, with a one-year warranty. The cordless Dolphin Liberty 400 costs $1,429, with three years, and it scrubs the waterline, which the corded model does not.
Price and warranty are the differences you can read off the store. The rest follow from what the cable was doing. It carried power from a supply on the deck for as long as the cycle ran, it bounded how far the robot could travel, and it gave you a line to pull the robot in by.
So where do those jobs go once the cable is gone? A battery robot hands each one to something else: the charge, the charger, and whatever its maker designed for getting it out of the water. Each handoff changes what you do at the pool, and one of them has already led to recalls.
Reach is set by the cable or by the charge
Figure
Reach limited by cord, or by charge
- Reach along the floorThe floor inside the cord. It is a circle around the supply, and shorter than the cord, because the cord has to drop the depth of the pool before it can run along the floor.
- Out of reachBeyond the cord, whatever the battery holds. A hard edge you can measure with a tape.
- RuntimeNo cord, so the whole basin is reachable. The limit is charge rather than cable length: when the pack is done the clean stops wherever it is, and the pack holds less each year.
A cable has to run over the coping and down the wall before it can cross the floor. So the floor a corded robot reaches is a circle around its supply, narrower than the cable is long, and in a pool longer than that circle the far end goes uncleaned.
The cable also twists as the robot turns, which Maytronics handles on the CC Plus with an anti-tangle swivel. A battery draws no boundary on the floor at all. Its limit is time: however much floor and wall the robot covers before the charge runs down.
How much time, though? The makers answer in units that don’t line up. Maytronics rates its corded and cordless Dolphins alike by pool length, with a cycle time. The cordless Scuba S1 is rated by area instead, 1,600 square feet of pool, and runs up to 180 minutes, or 270 in an eco mode.
The AquaSense 2 Pro is rated for 3,875 square feet, and its headline runtime, up to 11 hours, is for skimming the surface. For the cordless Dolphin EON 120d, Maytronics promises “up to 2 weeks of pool cleaning on one charge”, from cycle settings of 1.5, 2 and 2.5 hours.
| Robot | Power | Maker’s pool rating | Maker’s run figure | Waterline (per maker) | Warranty |
|---|---|---|---|---|---|
| Dolphin Nautilus CC Plus with Wi-Fi | Cable | Up to 40 ft long | 2-hour default cycle | No | 1 year |
| Dolphin Liberty 400 | Battery | Up to 33 ft long | 2.5-hour default cycle | Yes | 3 years |
| Dolphin EON 120d | Battery | Up to 50 ft long | 1.5 to 2.5-hour cycles, up to 2 weeks per charge | Yes | 3 years |
| Aiper Scuba S1 | Battery | 1,600 sq ft | Up to 180 min, 270 in eco mode | Yes | Not listed on product page |
| Beatbot AquaSense 2 Pro | Battery | 3,875 sq ft | Up to 11 hr surface skimming, no floor figure | Yes | 3-year full replacement |
Pool-robot reviewers describe shorter runs. The tester who described that haul writes that most cordless models “only run for 60 to 90 minutes on a full charge”, and warns that you may lose 10 to 30 minutes of that after a few months.
An authorized Maytronics dealer that also reviews pool robots puts the figure at 60 to 120 minutes. It calls cordless robots “dramatically underpowered” beside corded Dolphins, which it credits with more than 4,000 gallons per hour of flow.
So which is it? The flow ratings can’t settle it. The cordless makers rate the Scuba S1 at 4,200 gallons per hour and the AquaSense 2 Pro at 5,500. Every one of those numbers, the corded figure included, comes from someone selling robots.
Run time is easier to weigh. The long figures come with conditions: Aiper’s 270 minutes is eco mode, and Beatbot’s 11 hours is spent skimming. Maytronics, which sells both kinds, sets its cordless cycles at 1.5 to 2.5 hours. So a floor-and-wall clean from one charge runs closer to a couple of hours than a whole day.
Getting the robot out of the water
Without the cable, a cordless robot comes out however its maker designed it to. The Scuba S1 ships with a retrieval hook, and you will need it: cordless robots “typically sink to the bottom when they’re done”, the Dolphin dealer notes. So the hook comes out before the charger does.
Some are built to come up on their own. Beatbot says the AquaSense 2 Pro “automatically returns and parks on the water surface after cleaning or when the battery is low”. For the Scuba V3, Aiper advertises waterline retrieval with alerts in its app and a compact wireless charging dock.
The lift itself weighs about the same either way. The corded CC Plus is 20.8 pounds, and the cordless robots here run from 17.9 pounds for the Liberty 400 to just over 25 for the AquaSense 2 Pro. The difference is how often you make it. A cordless robot comes out every time it needs a charge.
Leaf season adds trips of its own. A basket that fills before the cycle ends has to be emptied mid-run whatever powers the robot, and the cordless bins here hold 3.5 liters in the Scuba S1 and 3.7 in the AquaSense 2 Pro.
With a corded robot, each emptying is another pull on the cable. With a cordless one it’s another round with the hook, or a wait for the robot to surface, on top of the trips to the charger.
Robovations database
What the Scuba S1 leaves to its owner
Aiper Scuba S1
Empty the debris basket; rinse the filter cartridge.
Rinse the unit with fresh water and let it dry, then charge it indoors on a dry surface away from the pool, using only the supplied charger. A full charge takes 3 to 4 hours.
Deep rinse of the filter cartridge under running water.
Check the treads and brush for embedded grit or tangled debris that could affect climbing.
Pool winterization; drain the robot and store it indoors in freezing climates.
As neededUse only the supplied charger, keep the unit on a hard non-combustible surface, and do not leave a charge running unattended overnight. Both CPSC recalls on Aiper's cordless line have been charging-path failures: the Elite Pro GS100 in August 2023 (recall 23-784, about 22,000 units, 17 reports of the battery overheating) and the Seagull Pro in March 2025 (recall 25-187, about 32,660 units, 19 reports of units melting, smoking or catching fire on charge). The Scuba S1 is the model CPSC published as the free remedy for the 2025 recall and is covered by neither recall itself.
Every stop the record names, placed on the interval it comes round. A larger dot is a task that returns more often.
Where the recalls happened
A cordless robot spends hours on a charger between swims, about 4.5 of them for the AquaSense 2 Pro. A corded robot never goes through that step, and it is the step two Aiper recalls concerned: the Elite Pro’s battery in 2023, and in 2025 the adapter of the Seagull Pro, the model Aiper had offered owners in its place.
How the pack ages is harder to pin down. The AquaSense 2 Pro carries a 13,400 mAh pack with no rated number of charge cycles, and the Scuba S1, Liberty 400 and EON 120d pages give no capacity at all. That early warning of 10 to 30 minutes lost within a few months is the nearest thing to a fade rate.
Add it up and the cable’s work still gets done. Charge sets the reach, a hook or a surfacing routine replaces the pull, and a battery carries the power, with a warranty as the only date anyone puts on it. You take on the charger, and every trip to it.
Back on the Maytronics store, the two warranties read differently now. The corded CC Plus comes with one year of coverage and has no battery to wear out. The cordless Liberty 400 comes with three years, and a battery inside it doing the job a cable used to do.
