EV tires are not the same as those of internal combustion engine cars. A number of factors makes them different from conventional tires, from noise to weight.
In this article, Vibroacustica explains the the main differences, focusing on noise and vibration issues. After all, this is our expertise.
What are the differences between electric vehicle tires and internal combustion engine cars?
The basic structure of tires is the same. Both have beads and treads, for example.
However, when making tires for electric vehicles, manufacturers have to deal with conditions that don’t exist in cars with a combustion engine. According to Ian Coke, quality analyst at Pirelli, these are the main ones:
- Weight: Electric cars are heavier, so the composition of electric vehicle tires is designed to support more load.
- Grip: the torque of electric cars is immediate. Therefore, to perform well on the road, you need more grip, which is not possible with the same type of tire on cars with a combustion engine.
- Noise: In general, electric cars are quieter. Therefore, tire noise becomes more noticeable, so they need to be optimised.
Why do electric cars need special tires?
The three characteristics above imply different needs for tires. They are among Pirelli’s priorities in the development of EV tires.
Because of the considerable weight and faster acceleration, tires need less rolling resistance, allowing a smoother ride. It also mean stronger constructions and use of more robust rubbers in manufacturing.
So, generally speaking, it can be said that EV tires need to be stronger. Otherwise, both drivability and performance suffer.
Another important point of EV tires is noise. In internal combustion engine cars, tire noise against alphalt is maked by the sound of the engine.
These and other components that emit noise do not exist in EVs. Therefore, the sound of the tires is much more evident in an EV.
Thus, tires need to be optimized to emit as little noise as possible. One solution found by Pirelli was the use of a sound-absorbing material placed inside the tire. It attenuates the sound waves that would otherwise be transmitted to the interior of the vehicle.
In terms of engineering, numerous tests and simulations are carried out to optimize noise levels. We do this type of work here at Vibroacustica, in a dedicated testing area.
Through specific equipment, and theoretical knowledge to assemble and interpret the simulations, we are able to understand how the tires emit sound, and how it is possible to improve performance.
For more details on EV noise sources, read this article on our blog.