Why do electric vehicles need special tyres?

The beauty of the design is in the details

Designers in companies are increasingly focusing on equipment that is one of the most important links in green vehicles, to the point of working with tire manufacturers to create models that are in line with the nature of the technical specifications for this type of car, given the difference between them and those that run on fossil fuels.

Electric vehicles have more mass and more torque than petrol ones, so experts think what most companies are striving for to make tires efficient and quiet looks interesting as it underscores the vast differences between electric vehicles and their conventional counterparts.

Car tires are very important parts of any vehicle, as they directly affect the safety of the occupants, and their quality and proper selection of the appropriate usually reduce the risk of accidents.

From this point of view, most manufacturers are keen to equip the green car with special tires for many reasons, including technical issues, the first of which is that the use of tires dedicated to electric cars improves the range of travel, as it is an important factor in the efficiency of the battery.

In the past, very few looked at the technology used in winter tires or even what makes a good racing tire. However, given the acceleration of the focus on electric cars, it seems that the coming period will witness competition between entities specialized in this aspect through research and experiments to reach the appropriate model.

The "RAS Technica" platform specialized in the automotive world highlighted this trend through the Italian tire group Pirelli, which is among the most prominent interested in creating new, more advanced models, and through this it seeks to advance a step in the overall ranking as it is the fifth largest producer in the world in this field.

Ian Cook: Introducing a load index that supports the heavy weight of green vehicles

Ian Cook, Quality Manager at Pirelli, a subsidiary of the Chitchinese Group, does not hide his company's interest in this aspect of excellence and exclusivity even more, as he says, "We like the design of the tire while designing the car."

This means starting OEM manufacturing many years before the car goes on sale, while it's still just a concept in development compared to the American company "Tesla", which Cook said, "They work in a different way, six weeks seems enough for them until you see a model of their innovative tire stuck to the asphalt."

While the Italian tire company is developing rubber for the auto industry, Cook asserts, "We get to know Tesla very well now."

But for an OEM tire of the type worn by a new car from the factory, "there are so many changes that if you don't work with the design team as soon as possible, you'll get caught up in them and development costs and times can continue."

The four black rubber rings on any important vehicle are clearly irreplaceable no matter the conditions, as they are the only parts that actually interact with the road, but electric vehicles have some quirks that complicate the life of the tires.

For one thing, electric vehicles are generally heavier than equivalent-sized conventionally powered cars and because range is so important for this market, lower rolling resistance is essential.

In fact, increasing rolling resistance by 20 percent can reduce the range by 5-8 percent. But the tire needs a lot of stability because the electric motors produce a lot of torque and are very low in their rev range.

"We had to introduce a new load index to be able to support the weights of these composites," says Cook. "I think we were the first to bring that up with Lucid and that was done by reinforcing the sidewall construction and by using synthetic textiles like aramid."

Once the tires can support the mass of the electric vehicle, they also need not to reduce their range.

Cook believes that a major limitation is that a lot of technology has to be used in regards to construction, especially in composites, and especially high-content silica compounds to work on rolling resistance.

Car tires are very important parts of any vehicle as they directly affect the safety of passengers and their quality and good selection reduce the risk of accidents

But this situation is very complicated by the fact that drivers of electric vehicles like to press hard on the accelerator pedal when setting off from traffic lights.

Experts therefore raise questions about how far to go for rolling resistance so that drivers are also able to get the required performance.

Most of the electric vehicles on the market now are more powerful than the driver imagines, such as the Tesla Model Y, Rivian, Lucid and Karma, so much so that Cook said, "These are high-performance vehicles. I wouldn't call them ordinary passenger vehicles."

While Pirelli has been able to make tires that offer these traits, the process involves compromising other characteristics and the most noticeable thing is the speed of wear as it may need to be replaced every year while conventional cars may not need to change it for an average of four years.

Tires need a great deal of stability when on the road because electric motors produce a lot of torque with very low rev range.

Another problem is, electric motors are nearly silent, so tire noise that might be unnoticeable in a conventional powered car becomes just as great as in an electric car.

Cook stresses that there are a variety of techniques because the tread pattern is one-sided. There has been significant uptake in noise cancellation systems that include open cell structured foam that is placed inside the frame.”

Pirelli has exclusively provided BMW with the first FSC-certified natural rubber and rayon tires to be used in the X5 Hybrid.

Experts say that equipping an electric car such as Renault ZEO, BMW i3 and Kia Soul with special light tires with a large diameter and a thin contact surface to increase the mileage covered by the battery charge requires research and innovation to reach a high degree of quality.

And the German news agency quoted a senior official in the German Technical Inspection Authority, Volker Blandow, as confirming that the thin tires have low rolling resistance and air resistance.

He pointed out that the Tesla S sports car, for example, is an exception to this rule, as it is equipped with wide tires, due to the large acceleration values, which are about 3 seconds from stability to a speed of one hundred kilometers per hour, as well as being equipped with a large battery.