Why don’t electric vehicles have gear boxs?

Electric vehicles (EVs) have revolutionized the 21st century in the automotive sector as we now see their unique design and operational features. One of the most interesting aspects of EVs is their lack of traditional gear. The most important difference between EVs and traditional internal combustion engine (ICE) vehicles is the absence of multi-gear transmission systems in the EVs. However, electric vehicles typically have single-speed transmissions or single-ratio gearboxes. In this blog post, you’ll learn why electric cars don’t have gears and why single-speed transmissions are used instead of multi-gear; then you come into the right place.

Why are there no gears in electric cars?

The electric motor is the heart of an electric vehicle that fundamentally separates the electric vehicle from the internal combustion engine of the traditional vehicle. And that’s why there’s been a great shift in electric cars that don’t have multi-gear transmission systems. Electric vehicles require advanced engineering that transfers the power of the ICE engine’s gearbox to the wheels. Why are there differences in electric cars, what has changed, and how does it work compared to traditional vehicles?

• • Torque and RPM Range: Electric motors give maximum torque at 0 RPM compared to traditional ICE vehicles, where RPM must be built to reach high torque. So, electric motors can immediately transmit power at high speeds in EVs. It differs from an internal combustion engine, which has to rev up to achieve its best torque. The low-end torque of electric motors that produce immediate power also means there is no need for multiple gears to control the level of power delivery for each speed.

• • Efficiency: Electric motors are far more efficient over various speeds (RPM). When RPM increases, the torque output of the electric motors goes down, which means the acceleration and efficiency of the electric vehicle are reduced at higher speeds. The lack of a narrow powerband in the traditional internal combustion engine-based vehicles with a limited RPM means that the ICE vehicles require multiple gears to run most efficiently at a relatively small, specific range. Electric vehicles have a broad power band that doesn’t need multiple gears as ICE-engine vehicles require.

• • Easier Drivetrain: The drivetrain in an EV delivers power from the electric motor(s) to the driving wheels because it does not require a complex gearbox. It consists of the battery, the controller, the electric motor, and the transmission. It also helps reduce the vehicle’s weight, cost, and maintenance. Even in the electric vehicle, there are no heavy engine components, which reduces the overall weight and lowers maintenance costs.

Types of Gears in the Vehicles

1. Single-Speed Transmission in Electric Vehicles

A single-speed transmission is a type of gearbox with only one gear ratio. You cannot change gears like the multi-speed transmissions found in most gasoline or diesel cars. Another key feature here is the single-speed transmission gear ratio, referred to as fixed gear ratio, where the power is transferred from its electric motor to its wheels. Even the Tesla Model Y uses a single-speed transmission with an acceleration from 0 to 60 mph in just 2.4 seconds. Moreover, the electric motor operates efficiently over a wide range of speeds, providing smooth acceleration and high-top speed without needing gear changes. Even if the car’s speed increases, the car does not need to change gears.

Suppose you are riding a bicycle and think it is a single-speed bicycle. When you pedal your cycle, it moves forward, and you don’t need to change its gears. And in the same way, the single-speed transmission works in an electric car. So, in electric vehicles, the electric motor provides power directly to the wheels through a single gear, and by doing this, the car moves smoothly and efficiently.

2. Multi-Gear Transmissions in High-Performance EVs

Although most EVs feature a single-speed, some high-performance models like the Porsche Taycan have multi-gear transmissions to boost performance.

• • Better Acceleration and Top Speed: Multi-gear transmissions can improve low-end acceleration and high-speed levels as the gear ratio can be optimized based on the driving condition. This helps EVs to be both high-performance and efficient, so they can accelerate quicker and reach higher top speeds without suffering from their efficiency.

• • More Complexity and Cost: Adding more gears will make the transmission more complex and costly. However, racing and high-performance driving cars can offer big performance advantages.

Benefits of Single-Speed Transmission and Multi-Gear Transmission

Related Posts