Why Electric Vehicles Still Require Conventional Disc Brakes

Electric vehicles (EVs) are becoming an increasingly popular choice among car owners due to their eco-friendliness and advanced features. However, despite not having a traditional internal combustion engine (ICE) with its numerous moving parts, EVs still require regular conventional disc brakes. This might seem redundant, but there are several important reasons behind this requirement.

Moving Parts in EV Drivetrains

Contrary to popular belief, EVs do have moving parts in their drivetrains. The drive shafts, differentials, and various gears play a crucial role in transmitting the motor's power to the wheels. These components are necessary to reduce the RPM of the motor to a speed suitable for the road wheels. This means that even without a typical ICE, EVs still have moving drivetrain parts, albeit fewer than those in ICE vehicles.

Regenerative Braking vs. Conventional Brakes

One of the key technologies that enhances EV efficiency is regenerative braking. As the name suggests, this system recovers some of the kinetic energy lost during deceleration by converting it back into electrical energy, which is then stored in the battery. However, regenerative braking encounters limitations, especially at higher speeds and when the battery is almost fully charged.

Regenerative braking is highly effective at lower speeds and when the driver uses the brake gently. However, when the vehicle is traveling at higher speeds or under heavy braking conditions, the system alone may not be sufficient to bring the vehicle to a complete stop. This is where conventional disc brakes come into play.

Legislation and Emergency Scenarios

Another critical factor is legal compliance. Most countries require vehicles to have conventional brakes as a mandatory safety feature. In addition, EVs still need emergency brakes for situations where the regenerative braking system might fail or when the driver needs to stop the vehicle abruptly.

Bulk of Braking is Handled by Regenerative Braking

While EVs do rely heavily on regenerative braking, it is not the sole solution for stopping the vehicle. In normal driving conditions, at lower speeds, most of the braking is actually handled by the regenerative system. This minimizes the wear and tear on the conventional disc brakes, especially since friction brakes are only engaged at high speeds or when the process of one-pedal driving cannot be used effectively.

For instance, in one-pedal driving, the driver uses the accelerator pedal to control both acceleration and deceleration, with regenerative braking handling the majority of the braking action. Friction brakes are only engaged when the vehicle is traveling at high speeds or when one-pedal driving is not sufficient. This method is becoming more popular in modern EVs and helps reduce the need for conventional braking.

Possibility of Brakes Wearing Out

Despite the effectiveness of regenerative braking, there is still a possibility that friction brakes could wear out over the lifespan of the vehicle. This is particularly relevant in situations where the driver might abuse the brakes or in extreme circumstances where heavy braking is required. However, in the typical driving scenario, the amount of wear on the friction brakes is minimal, thanks to the regenerative braking system.

Conclusion

Electric vehicles do have a need for conventional disc brakes, even though their drivetrains contain fewer moving parts compared to internal combustion engine vehicles. While the regenerative braking system is highly effective in most scenarios, there are always situations where conventional brakes are necessary. These include legal requirements, emergency braking, and extreme driving conditions. Understanding the role of both types of braking systems helps in the safe and efficient operation of EVs.