Electric boat batteries

Inspection and diagnosis:

• A thorough assessment of the current state of your boat battery, to find any faults or wear.
• Diagnostic testing of your battery's capacity, its performance and its expected remaining life.

Repair and cell replacement:

• Repairs that get a faulty boat battery working properly again and extend its life.
• Cell replacement of worn batteries, including replacing the cells and other key parts, to bring the battery back to as-new condition.

Battery replacement:

• Supply of new batteries as a cost-effective answer for batteries that are old or beyond repair.
• The option to upgrade to a battery with a higher capacity, or to a newer technology such as lithium-ion, for better performance and a longer life.

Advice and recommendations:

• Advice on which battery best suits your boat and the way you use it.
• Practical tips on maintaining and correctly charging your battery so that it lasts longer.

Lithium technology has changed the battery world, and you notice it in boating too. Because of their chemistry, lithium batteries work differently from traditional lead-acid, AGM and gel batteries. In a lithium battery, lithium ions move between the electrodes as the battery charges and discharges. A big plus is that lithium batteries do not mind which way up they are fitted. Thanks to their solid construction they can be mounted in any position, which makes them very versatile in an electric boat.

A lithium battery in your electric boat has several advantages. First, lithium batteries can be discharged almost completely, to 95-100% of their capacity, without damage. That is considerably more than the 50-80% you can use with lead-acid, AGM and gel batteries. They also weigh about half as much: a 12V 100Ah lithium battery, for example, weighs only around 14 kg. That makes transport and installation a good deal easier. Lithium batteries need almost no maintenance either, which suits long-term use. And they can be mounted in any orientation, so they fit well in awkwardly shaped or tight spaces, as in electric boats, camper vans and caravans.

When you are looking for a suitable battery for an electric outboard motor, there are several things to take into account. What a boat battery has to do can differ quite a bit from other kinds of battery, such as e-bike or car batteries.

Capacity and range

As with e-bikes, the capacity of the battery, measured in Ah (ampere-hours), is the figure to look at first. A higher Ah value means a longer range, which is especially useful on longer trips.

Voltage and power

The voltage of the battery, measured in volts (V), has to match the electric outboard motor. Most modern electric outboard motors are designed to work efficiently at higher voltages, which gives better performance and efficiency.

Battery type

Several types of battery are available, including lead-acid, lithium-ion and AGM. Lithium-ion batteries are generally lighter and more efficient, but they also cost more. Lead-acid batteries are cheaper, but they have a lower energy density and weigh more.

Durability and maintenance

Look at how durable the battery is and how easy it is to maintain as well. Some batteries stand up better to conditions on the water and need less maintenance, which saves money in the long run.

Safety

Make sure the battery meets all safety standards, particularly because you are dealing with water and electricity. Consider a battery with built-in protection against overcharging, short circuits and overheating.

An electric launch makes for comfortable, cleaner boating. The advantage you notice first is the silence: the electric motor makes no noise at all, so it is peaceful on board. An electric launch is also kinder to the environment, because it emits no CO2. The motor needs very little maintenance, which saves money over time. With a powerful battery pack you can be on the water for 6 to 10 hours in normal conditions, which is plenty for most day trips.

There are limitations to weigh up as well. Waterside charging points are still scarce, and charging the battery takes time. So you need to plan your trips carefully. The top speed of an electric launch is generally lower than that of a petrol model, which counts against it if speed and water sports are high on your list. Finally, an electric launch often costs more to buy, although lower maintenance costs can offset that, as can choosing a durable, powerful battery pack that gives you the longest range.