Robot Mower Winter Storage: The Protocol That Saves Your Battery

TurfNav · Published October 2026 — in season now, because this job cannot be done in March · Procedure synthesizes manufacturer storage guidance across Husqvarna, Navimow, Mammotion, and Worx families; your model's manual governs where it differs

Every spring, owner forums fill with the same post: the mower went into the garage in November, came out in March, and the battery is dead — not tired, dead, unable to take a charge at all. Owner post-mortems repeat the pattern for pack after pack, across brands: the machine was stored at or near 0% charge, in a cold space, for months. Lithium packs self-discharge slowly; a pack parked empty drifts below the floor its charger will recognise, and no spring ritual resurrects it. The replacement is $150–$350 when the pack is a user part, more when it's a dealer job.

The whole protocol below takes about an hour. It is the cheapest hour in robot mower ownership.

When to store

Store when growth stops and night frosts begin — for most northern lawns, late October through November. Don't run the mower into frozen ground "one last time": brand fault tables include battery-temperature lockouts, and a pack working at the edge of its temperature window in November is wear you don't need. Pick a dry day; nothing below works well on a wet mower.

The mower: clean, charge, rest

1. Final clean, power off and battery isolated. Brush and scrape the deck, blade disc, and wheel treads clear of compacted clippings — packed grass holds moisture against metal all winter. Wipe camera lenses and LiDAR windows with a soft cloth. Let the machine dry fully indoors before storage; storing a damp mower is storing corrosion.
2. Blades: inspect now, decide now. Fit a fresh set in spring regardless — but note their state today, because a disc that's bent or a carrier that's cracked is a winter parts order, not a spring surprise. [AFFILIATE LINK: robot mower razor blades]
3. Charge to the manufacturer's storage level. This is a published specification for your pack, in your manual — follow it exactly. The principle behind every brand's number is the same: a partial charge, not empty and not brimmed, because both extremes age a parked pack. Do not park it at whatever charge the last mow ended on, and do not leave it sitting on a live charger for four months unless your manual explicitly prescribes that.
4. Power fully off. Use the manual's full shutdown/storage mode if your model has one. If your pack is user-removable and the manual recommends indoor pack storage, the pack comes inside with the mower — same room, same moderate temperature.
5. Store indoors, dry, off the floor. A garage shelf or a dry basement beats a cold floor slab: off the concrete, out of the frost line's worst, away from the dehumidifier-vs-damp corner argument entirely. Store it on its wheels or per the manual's orientation — not resting on the blade deck.
6. Mid-winter top-up, if your manual calls for one. Some packs want a check charge mid-storage. Put it on the calendar now, in January, or it will not happen.

The charging station & the power supply

• The station can usually stay in the yard — docks are outdoor equipment rated for weather — but a cover keeps ice, UV, and nesting tenants out of the contacts, and costs little. [AFFILIATE LINK: charging station dock cover]
• The power supply comes inside. Unplug it, coil it dry, store it with the mower. Outdoor winter is what power supplies' 5–7-year lifespans are counting against; there's no reason to spend one on a dormant dock.
• Clean the contacts before you cover anything. Oxidation that starts in November is a "docked but not charging" fault in April. Wipe contacts on dock and mower dry and clean (see docking faults).

The RTK antenna: the position is the point

Wire-free owners have a component wired owners don't: the reference antenna, whose surveyed position anchors your entire map. Handle it with that in mind:

• Best option: leave it mounted. If the antenna and its pole are weather-rated and secure (they are designed to live outside), leave them exactly where they are. A winter in place costs nothing and preserves the map's reference perfectly.
• If it must come in, mark the position first. A moved antenna is spring's most predictable self-inflicted fault — the "antenna was moved" error and a forced remap. Mark the pole's exact position and orientation before removal, return it to the marks in spring, and budget a remap anyway if the app insists.
• Network-RTK (cloud) owners: no home antenna exists — your winter list is the mower, the dock, and the supply. Check your connectivity/service status in spring before assuming a hardware fault (terms vary by brand and model year).

The boundary wire: it stays, the ends don't fend for themselves

• The buried loop stays buried. Freeze-thaw is a known break cause you cannot prevent — but the spring walk (below) finds the damage before the mower does.
• Protect the exposed ends. Where wire meets the station, connections are the corrosion point: if you disconnect wire ends from the station for winter, seal them against moisture (gel-filled couplers are the same parts you'd splice with [AFFILIATE LINK: boundary wire couplers]) and note which terminal each wire came off. Photograph the terminal layout before touching it.
• Record your splices. Every repair joint in your loop is a spring suspect. If you haven't mapped them, this is the winter to start the list (see the wire-break protocol).

Spring recommissioning checklist (pin this for March)

1. Retrieve the mower; inspect deck, disc, wheels, and sensors before power-up.
2. Charge fully; run a timed runtime check against the rated figure — a pack at ~60% of rated is in its replacement year (see the battery protocol).
3. Fit fresh blades.
4. Reconnect the power supply and station; clean contacts; confirm the station LED state is healthy before the mower ever reports a fault.
5. RTK owners: confirm antenna position; let the app validate the fix before the first mow. Wired owners: walk the exposed wire and every splice.
6. Apply pending firmware updates, confirm app/connectivity status, then mow a supervised first session at a conservative schedule.

Something already wrong? Signal, loop & positioning failures, diagnosed in order. Still deciding what to buy before spring? The buying guide compares the full field — winter is exactly when to do that homework.