Why do electric vehicles need special tires?
The first experiences of operating the new generation of vehicles, electric cars, have shown that they also require a different approach to the concept of tires. To begin with, let's understand the terminology.
Among the vast variety of modern vehicle typologies, several basic types can be distinguished:
ICE (Internal Combustion Engine) – this is the familiar car with an internal combustion engine;
HEV (Hybrid Electric Vehicle) - a vehicle that uses a combination of an electric power unit (electric motor) and a power unit on another type of fuel (e.g. gasoline engine) for movement;
PHEV (Plug in Hybrid Electric Vehicle) – a hybrid electric vehicle with a larger battery, the "Plug In" prefix means that the car can also be charged from an external power source;
BEV (Battery Electric Vehicle) – a vehicle that uses an electric power unit (electric motor) with an accumulator battery as the sole source of power.
At the same time, as we all understand, the operation of an electric vehicle revolves around the electric motor and accumulator batteries, which, in fact, provide the energy for movement. At the same time, batteries have a significant weight, and power units (electric motors) are not always located in the engine compartment, but, as a rule, near the axles, which fundamentally changes the distribution of the vehicle's mass between the axles compared to a classic car. And besides, batteries add extra weight to the vehicle: an electric car, on average, becomes 200-600 kilograms heavier, depending on the type of electric vehicle. The impact of these factors leads to accelerated, and often incorrect, wear of ordinary car tires.
A separate factor affecting wear is the dynamic indicators of acceleration and braking. The fact is that the torque of the electric motor is almost uniform throughout the entire range, which is why maximum power can be obtained from the first seconds of start. The dynamics of acceleration in electric vehicles are significantly higher than in conventional cars. For example, in premium electric vehicles, the acceleration dynamics from 0 to 100 km/h are often faster than 4 seconds. With such acceleration, in the first fractions of a second, the rubber compound of classic tires is subjected to colossal loads, while it is strongly deformed, which leads to faster wear of ordinary tires.
There is also the phenomenon of "acoustic discomfort". The fact is that most of the noise in a car is generated by the working engine and transmission elements. When you remove these elements from the car design, the noises they produce disappear, and then the noise from the tires becomes the most noticeable!
The eternal struggle of tire manufacturers to reduce the rolling resistance coefficient in new "electro-realities" has acquired a new meaning. Why? Because reducing the rolling resistance coefficient by some amount can allow the vehicle to travel additional kilometers and even tens of kilometers with the same level of charge and battery capacity.
Thus, when developing tires for powerful premium electric vehicles, designers need to consider many requirements to create a tire that can meet consumer expectations.