Electric vehicles are eco-friendly and they have all convenient driving features, but what about their top speed?
Generally, EVs have lower top speeds than conventional gas-powered vehicles, and here are the 5 reasons why. Meanwhile, you should know the car models that are not speed-limited.
Table of Contents
1. Designed to Preserve Battery Charge
If you consider internal combustion engines or ICE vehicles, their top speed is limited due to their drivetrain or motor oil.
But the case is different for EVs.
The top speed of electric vehicles is limited to keep the battery and circuits below a certain temperature. Because if the speed of EVs is double, the battery will overheat and degenerate faster.
Manufacturers aim to make EVs sustainable for daily commutes, but a higher top speed could interfere with that by making the battery degrade sooner than its warranty.
In addition, motor RPMs have come into play when considering the top speed of electric vehicles.
For instance, Tesla has put the electric motor of its EVs in carbon ceramic wrap to prevent it from coming into contact with the stator and causing friction.
You can check the shocking top speed and acceleration for Teslas here.
(spoiler alert: Even the Model S goes 0-60 in less than 2 seconds – yeah, two-seconds!)
The Tesla Model S operates at about 20,000 RPMs with a speed limit of 162 mph by the company.
The automaker is inventing ways to complete its aim of EVs operating at high RPMs.
Preserving battery charge is the primary reason why manufacturers limit the acceleration of electric vehicles.
According to a study, if an electric vehicle is driven at more than 60 mph (102 km/h) it will drain the vehicle’s battery 68% more than when it’s driven at less than 30 mph (50 km/h). The study confirms that to keep an EV’s battery in optimum condition, it’s best to follow a certain speed limit.
The speed-limiting features make electric vehicles sustainable for daily driving. As automakers plan to turn more than 80% of their fleets electric in the next decade, they aim to make EVs the most convenient transmissions.
2. Protecting the Brakes
In addition, a high top speed would impact the brakes of the EV.
If an EV operates at maximum speed, the brakes would wear out and its battery would drain in under 10-12 minutes.
The Tesla Model 3 has a speed assist feature, so the driver can set their own speed limit while driving.
However, there are still some restrictions as you can’t get past a certain speed or a warning signal will flash on the console.
This, again, is to protect the brakes that would otherwise wear down too quickly!
3. Gear Ratio Is a Factor
The gearing ratio is basically how fast a gear rotates in comparison to other gears.
EV manufacturers limit the top speed of the vehicles by a gearing ratio that only produces enough torque needed by drivers on a daily basis. That means the vehicle only has a range of speeds sufficient for daily commutes.
This process also impacts the acceleration of electric vehicles, but mainly their top speeds. EVs only have a single gearbox that gives them a higher rev range than other conventional vehicles.
Though we do have a few EVs with multiple gears.
For instance, a standard ICE vehicle has a rev range of no more than 7000 RPMs whereas most EVs can go up to 20,000 RPMs, as mentioned above.
Multiple automakers have installed double gearboxes in EVs, such as the Porsche Taycan.
Two speed gearboxes add to the weight of the vehicle and have an impact on its efficiency.
Many potential buyers wonder if EVs have gearboxes similar to petrol-powered vehicles, but in truth, EVs do not need multiple gears to operate.
The gearboxes balance wheel speed and torque to maximize the performance of the vehicle.
Tesla electric vehicles have a gearing ratio of 1:10, meaning the vehicle’s drive wheels only rotate once per ten revolutions of the electric motors within the vehicle.
4. Weight of the Vehicle
Horsepower only influences the top speed of a vehicle depending on the gear ratio, but that’s not the only limiting factor when it comes to the top speed of an electric vehicle.
The aerodynamics and weight of an EV can impact its top speed. For instance, electric vehicles don’t have enough horsepower to get towed, which makes it a severe problem for drivers who might experience trouble cranking up the engine on a busy road.
If we consider the aerodynamic drag of electric vehicles, it increases every time the vehicle accelerates, which affects its battery charge.
So, manufacturers keep the top speed of the EVs limited to preserve their battery.
The weight of the electric vehicle mostly comprises the added batteries because that makes it heavier than conventional gas-powered vehicles. In addition, the framework and metal armor of an electric vehicle increase its weight, making it difficult for it to perform at higher top speeds.
You can see here just how heavy batteries for electric cars are.
Another reason why EVs don’t have high acceleration is their simple technology.
There are multiple complex technologies that can increase the top speed of EVs but that would make them less sustainable for daily commutes. For instance, a complicated converter would provide the exact voltage needed to operate electric vehicles at higher speeds.
That would not only increase the cost of the electric vehicle but make it more.
However, the automotive industry is more concerned about EVs range and safety than its acceleration, because consumers look for safer vehicles rather than faster ones.
As mentioned above, to make electric vehicles safer for the general public to drive,m automakers rarely focus on the speed and acceleration of electric vehicles.
EVs are the future of the automotive industry as manufacturers around the world aim to stop producing gas-powered vehicles as a step against climate change.
Most potential consumers prefer to drive at slower speeds which means if the EV industry focused more on acceleration and higher top speeds, they wouldn’t be making any sales ever.
For instance, conventional vehicles have a rev limiter to ensure they don’t surpass the speed limits and put the driver at risk.
Not only does slower speed add to the safety feature of electric vehicles, but it also makes them live up to their lifespan.
Multiple Tesla consumers sued the company for misleading information about the horsepower but the reason turned out to be something else.
The company used the combined capability of its motor shafts as the horsepower of the vehicle. But they no longer do that to avoid any confusion amongst potential buyers in the market.
Moreover, only a fully charged EV can give maximum ratings of horsepower.
When the battery of an electric vehicle slowly drains, the horsepower is also reduced which makes it difficult to achieve high acceleration on road. In conclusion, the safety of the driver and other road users is the main reason why automakers do not add a complicated system to increase the top speed of electric vehicles.
6. Tires Wear Down Quickly
If vehicles, even conventional ICE vehicles, are driven aggressively or at high speeds, the tires can wear fast.
The same reason why automakers do not let their vehicles achieve higher speeds than the limit.
Each set of tires comes with a different speed rating mentioned on the side of the tire.
Driving at higher top speeds would damage the tires and have users replace them very often.
Even if the tires don’t completely disintegrate, regular fast driving can make them wear down more quickly than driving at a normal speed. Not to mention the friction generated by EV tires when you drive at top speed impacts their lifespan.
When you drive an electric vehicle at a higher speed, it involves a lot of sudden braking on the road, which affects the tires of the vehicle.
So not only is their tire damage involved, but there’s also a potential risk of accidents when driving at high speeds.
If you consider all EVs in the market today, more than half of them are capable of achieving much higher speeds than the speed limit authorized without ending up with too many problems.
That is because as time passes, automakers are trying to improve the technology used in electric vehicles to enhance their sales.