Electric Outboard Care: Battery Storage, Connectors, Saltwater Rinse and Updates

Most electric outboards will only run with a magnetic key or lanyard in place. Torqeedo says to attach it to your wrist or life jacket so the motor stops instantly if you fall overboard. Electric motors are silent, so people in the water may not hear a spinning prop. Treat it with the same respect as a gas engine.

• Use only the maker's charger or one the maker approves. ePropulsion's FAQ says third-party chargers aren't allowed under its warranty, and that with third-party batteries the motor can't read the battery's status (so the range display and protection strategy don't work properly).
• Adding a second battery for range? Check the maker's rules before wiring batteries in parallel. ePropulsion, for example, says its E-Series batteries may only be paralleled with the same model of the same age, need a communication terminator, and must be switched on and off master-first; getting the order wrong can damage them.
• Charge in a dry, ventilated spot, out of direct sun and away from anything flammable, and don't leave a charging battery unattended for long periods.
• Torqeedo says its lithium batteries have no memory effect, so you can fully charge after every trip whatever the display shows.
• Heat is the enemy. Torqeedo notes capacity loss speeds up if the battery is kept hot or always stored fully charged, and recommends taking the battery out of the sun and keeping it somewhere cool after use.
• Expect some gradual loss. Torqeedo estimates about 4 percent of capacity per year in normal recreational use.
• Charging while the boat is in the water is a shore power job. Mercury's Avator care page says to charge on the water only through an approved locking shore power inlet on a boat wired for shore power, with the charger plugged into a permanently installed GFCI outlet aboard. Never run a household extension cord from a dock or shore outlet to a charger in a floating boat: a fault can energize the water around the boat, which can kill swimmers. If your boat isn't wired for shore power, take the battery ashore to charge it, or have a marine electrician install a proper system. See the shore power safety guide.

Most electric outboard problems that aren't a flat battery start at a plug. Before connecting:

• Make sure both halves of every connector are dry and free of sand and salt.
• Look inside with a flashlight for green or white corrosion or bent pins.
• Put the caps back on any unplugged connector. Torqeedo's own troubleshooting for a motor communication error is to switch the system off and check the data cables and plugs for corrosion. If your manual approves a contact protectant spray, use it as directed; if it doesn't say, ask the dealer first.

ePropulsion says an outboard isn't meant to sit submerged for long periods and recommends tilting it up after every use. Leaving the lower unit in the water invites marine growth and corrosion, especially in salt water.

ePropulsion recommends rinsing with fresh water after each use in salt water. Use a gentle spray from a garden hose on the shaft, motor pod, prop, clamp bracket and tilt mechanism. Keep the spray off the battery and the charge port unless your manual says that's fine, and never use a pressure washer on any part of the system. Let everything dry before you put covers on or connect plugs.

With the system off and the key removed:

• Look for nicks, cracks or bent blades. Mercury's Avator prop, for example, is a composite; check composite blades for cracks, not just dings.
• Look behind the prop for fishing line or weed wrapped around the shaft.
• Check the skeg (the fin under the motor) for cracks or damage after a grounding.
• Remove the prop at least once a season if your manual allows, clean the shaft, and reinstall with the correct pin, washer and nut. Electric motors are efficient, so even a slightly damaged prop costs you noticeable range.

Electric outboards still have metal parts in the water and many carry sacrificial anodes. ePropulsion says its Spirit 1.0 Plus has four, on the clamp and the lower unit, and advises replacing anodes once they're worn to about half their original size. Never paint them, and make sure they're tight and on bare metal.

Wipe the head, tiller and cables with a soft cloth and mild soap. Look for:

• Cracked or chafed cables, especially where they bend at the tiller or connect to the battery
• Loose clamp screws or a wobbly tilt mechanism
• Damaged seals or cracked housings where water could get in A cracked housing on the motor head or battery is a reason to stop using it and contact the dealer.

Electric outboards run on software, and updates can fix bugs and improve range estimates. Mercury says the Avator comes with a SmartCraft Connect Mobile module and can be updated wirelessly through the Mercury Marine app. Other makers update through an app or a dealer. When updating:

• Start with a well-charged battery and a good phone connection.
• Don't switch off or disconnect anything until the update finishes.
• Check the controls afterward. Torqeedo notes that a software update can erase the remote throttle calibration; its manual explains how to recalibrate.

This is the most important thing for battery life. Follow your maker's number:

• Torqeedo: for winter storage of up to six months, unplug the batteries and store them at about 50 percent charge. Check every eight weeks and recharge to 50 percent if it has dropped.
• ePropulsion (Spirit): store in a dry place at around 60 percent charge and charge it every three months.
• Others: check your manual. Many makers say not to store lithium batteries completely full or completely empty.

• Keep the battery indoors in a dry, moderate-temperature space, off concrete floors and away from heaters, direct sun and anything flammable. Avoid freezing sheds and hot attics; your manual gives the allowed storage temperature range.
• Store the motor clean, dry and upright or in its bag, with connector caps on.
• Put a reminder in BoatMend for the next charge check.

• In the car, secure the battery so it can't slide or be crushed, keep its terminals and connectors capped, and don't leave it baking in a hot vehicle.
• Flying: the FAA limits spare lithium-ion batteries in passenger baggage to 100 watt-hours each, or up to 160 Wh each (two at most) with airline approval, in carry-on only with the terminals protected. Electric outboard batteries are usually far bigger (Torqeedo lists 915 Wh for the Travel 1103 and Mercury lists 1 kWh for the Avator 7.5e), so they can't go in your luggage. Ask the maker or dealer about legally shipping a battery as hazardous material, or plan to rent or buy locally.
• The FAA also warns that lithium batteries can overheat on their own (thermal runaway), especially if damaged, wet, overcharged or poorly packed. Pack carefully even for a car trip.

If a battery is swollen, cracked, was submerged, or holds far less charge than it should, stop using it. Contact the maker or dealer for inspection or replacement and for proper recycling. Never put a lithium battery in household trash, and don't try to open or repair one yourself.