As an emerging choice for ship propulsion power, electric boat outboards have gradually gained prominence in the market with the development of DC brushless motor technology and battery technology. They are widely used in areas such as leisure and entertainment, and fishing industries, owing to their advantages like environmental - friendliness and low noise. Electric boat outboards can be classified into various types according to different criteria.

From the perspective of the motor position, they can be divided into lower - mounted motor type and upper - mounted motor type. In the lower - mounted motor type, the motor is installed at the lower part of the boat outboard, and the output shaft of the motor directly drives the propeller shaft to rotate. This structure commonly uses DC brushless motors, which have a high energy conversion rate, direct kinetic energy transmission, and low energy loss. Moreover, the intermediate connector can be optimized in design from the perspective of fluid mechanics to reduce the water resistance coefficient. The overall structure is simple, with a low failure rate and high reliability. However, due to the space limitations in the lower part, this structure is usually used for electric boat outboards with relatively small horsepower, such as the outboards below 8 horsepower from the German company Torqeedo. In the upper - mounted motor type, the motor is placed at the top of the boat outboard, and the kinetic energy of the motor is transmitted to the propeller through the transmission shaft in the gearbox. The advantage of this design is that the motor in the upper part is less restricted by space, and its volume can be relatively larger, making it suitable for outboards with larger horsepower. For example, the 20 - horsepower, 40 - horsepower, and 80 - horsepower outboards from Torqeedo adopt this design.

According to the position of the storage battery, they can be categorized into built - in type and external type. Smaller - horsepower electric boat outboards have relatively low requirements for battery capacity, so the built - in battery type is often used, which is more convenient to use. On the other hand, larger - horsepower electric boat outboards require a large battery capacity, and usually need external batteries to meet the energy supply.

Classified by voltage, there are 12v electric boat outboards, 24v electric boat outboards, 48v electric boat outboards, etc. Among them, 12v electric boat outboards can be further subdivided according to size, such as 18 - pound, 30 - pound, 40 - pound, etc. Different specifications are suitable for different types of boats and different passenger capacities. For example, 18 - pound and 24 - pound ones are suitable for single - person small rubber boats, and 30 - pound to 58 - pound ones are suitable for small boats carrying 2 - 3 people.

Based on power, they can be divided into types with power less than 20hp, 20hp - 50hp, and greater than 50hp. Electric boat outboards of different powers are suitable for different ships and usage scenarios. Small - power ones are suitable for small leisure boats, while large - power ones can meet the needs of large ships or operations with high power requirements.

Each type of electric boat outboard has its unique advantages and applicable scenarios. When choosing an electric boat outboard, users need to comprehensively consider factors such as the type of boat, usage requirements, and navigation environment, so as to select the most suitable electric boat outboard and obtain a better user experience and economic benefits.