Electric car manufacturers keep on trying to improve the all-electric range of electric cars. We know that there are a lot of factors that affect the performance of an electric vehicle.
The tires are one of those factors.
Today we are going to check the characteristics of the electric vehicle tire, impact of tire pressure on the performance, and Airless tire for electric vehicles.
Electric vehicles are heavier than conventional IC engine vehicles. So it demands tires that could bear more weight and transfer more torque to the road when the vehicle moves.
The powertrain of an electric vehicle doesn’t make much noise and the tire noise would be more noticeable in electric cars than IC engine vehicles.
To reduce the noise, tire manufacturers add a foam inlay inside the tire.
Rolling resistance and electric car range
The component of force to overcome the rolling resistance is “m.g.Crr. cos (X)”
The coefficient of rolling resistance depends on the tire and the surface where the vehicle travels.
It is estimated that the loss in electric vehicles accounts for 90 Giga Watt-hours per year to power around 50,000 households in China.
Electric car tires from many manufacturers such as Continental have a “tall and narrow” shape to reduce the rolling resistance.
Geely Research Institute and ExxonMobil conducted a study and published a research paper on SAE international about the impact of pressure on electric vehicle range.
They had found that in the overall life of an electric car, the change in the rolling resistance due to the fluctuations in the air-pressure alone could increase energy consumption by 4%.
It showed that the reduction in pressure loss and rolling resistance could help out the carmakers to use lighter batteries in the car.
There are tire pressure alert systems in vehicles that could monitor tire pressure under-inflation by 20%. The latest systems are programmed for a trigger of 2.5 %.
But all those systems could not improve the efficiency of electric vehicles.
The above-mentioned study shows that greater attention to the tire pressure loss across the lifetime of electric vehicles could improve EV range by 3 – 7%.
Airless Tire for electric cars
Here the airless tires come into the picture.
Airless tires are puncture resistant. They are constructed by a band of rubber encircling polymer spoke around an aluminum hub.
Michelin, a France-based tire manufactures showed the prototype in 2005 and commercially launched in 2012.
These tires could be lighter than air tires and would reduce the total weight of the car in the future.
General Motors announced that they would launch passenger cars with Michelin airless tires in early 2024. They are jointly testing the prototype tire on Chevrolet Bolt EV and then moving to other vehicles.
According to the company, airless tires result in a lot of benefits like less downtime, near-zero maintenance, and more peace of mind as the risks of flats are eliminated.
In electric vehicles, you may see that the improved rolling resistance characteristics reduces energy loss and result in a better all-electric range.
The saved energy would be useful for other purposes.
The tires of the vehicle have impact on the range of electric vehicle. Studies shows that the tire pressure variation results in an additional 4% energy consumption in an electric vehicle.
It is important in an electric vehicle since the improvements of tire characteristics helps the car makers to reduce the battery size.
Airless tires are being tested by Michelin and GM on Chevrolet Bolt EV and we could see them on road by 2024.
- Tire pressure affects the range of EVs
- Greater attention to the tire pressure loss could improve the range of EVs by 3-7%
- Airless tires could help out the vehicles in many aspects