Tires: EV vs. Traditional

The fundamental difference between conventional tires and electric vehicle tires stems from underlying differences in vehicle power and construction, resulting in distinct design objectives from the outset.

Conventional tires primarily serve the engine and transmission systems of fuel-powered vehicles, prioritizing a balance between the three fundamental requirements of handling, wear resistance, and quietness. Energy consumption considerations are limited to the secondary aspect of reducing rolling resistance to reduce fuel consumption.

Electric vehicle tires must simultaneously adapt to two core components: the motor and the battery. On the one hand, they must withstand the impact of the motor's instantaneous high torque, and on the other, they must support a battery that is 30%-50% heavier than a comparable fuel-powered vehicle. Furthermore, they must prioritize low rolling resistance for extended range, completely reshaping design priorities.

This article will explain this from four perspectives: performance, the characteristics of conventional tires (for gasoline-powered vehicles), the characteristics of electric vehicle tires, and the key reasons behind this.

Regarding the rolling resistance coefficient, conventional tires (for gasoline-powered vehicles) generally have a rolling resistance coefficient between 6.5 and 8.5 kg/t, with relatively low industry requirements. However, the rolling resistance coefficient of electric vehicle tires is generally below 6.0 kg/t, with some high-end products even reaching 4.5 kg/t.

The core reason for this discrepancy is that the range of electric vehicles is highly dependent on low rolling resistance. Industry data shows that every 10% reduction in rolling resistance increases the range of electric vehicles by 3%-5%.

In terms of load-bearing capacity, conventional tires (for gasoline-powered vehicles) are designed based on the vehicle's curb weight, resulting in relatively limited load margins. The load-bearing index of electric vehicle tires is 10%-20% higher than that of conventional tires of the same size.

This is because the battery in electric vehicles accounts for a significant portion of the vehicle's weight. For example, the Tesla Model 3's battery weighs approximately 500 kg, significantly exceeding the overall vehicle weight of gasoline-powered vehicles in its class. This requires a stronger tire load-bearing structure.

In terms of impact resistance, conventional tires (for gasoline-powered vehicles) focus more on handling road bumps and pay less attention to torque shock. Electric vehicle tires, on the other hand, have a more robust carcass structure and incorporate high-strength materials into the sidewalls.

This is primarily due to the instantaneous torque generated by the motor upon startup, which is 2-3 times that of the engine. For example, the instantaneous torque of a Tesla motor can exceed 400 Nm. This high torque can easily cause impact damage to the tire's tread and sidewalls, so electric vehicle tires require stronger impact resistance.

Finally, regarding quietness, conventional tires (for gasoline-powered vehicles) achieve noise reduction solely through basic tread design. In terms of performance, quietness takes a backseat to wear resistance. Electric vehicle tires, on the other hand, utilize a combination of "quiet treads + sound-absorbing materials" to achieve 20%-30% quieter performance than conventional tires.

This is because electric vehicles lack engine noise. During driving, tire noise becomes the primary noise source, directly impacting the driver and passenger experience. Therefore, quietness is a crucial design characteristic for electric vehicle tires.

Electric vehicle tires feature targeted adjustments to their material formulation and internal structure, features not found in conventional tires.

Optimized Material Formula

Low Rolling Resistance Material: Highly Dispersed Silica is added to replace traditional carbon black, reducing friction between rubber molecules while maintaining grip. This high-end material is rarely used in conventional tires.

High-Strength Tread Compound: A blend of aramid fiber (five times stronger than steel) enhances the tread's tear resistance, mitigating the risk of tread slippage caused by the high torque of the electric motor.

Lightweight Material: A lightweight rubber compound is used on the sidewalls to reduce tire weight and indirectly reduce energy consumption. Conventional tires prioritize rubber wear resistance over lightweighting.

Internal Structure Adjustments

Reinforced Carcass: A double-layer polyester cord is used instead of the standard single-layer structure to improve carcass deformation resistance and prevent sidewall bulging under the weight of the battery.

Optimized Bead: Increased bead contact area and the use of high-strength steel wire rings enhance tire-wheel contact and prevent slippage caused by the high torque of the electric motor.

Quiet Structure: Some high-end tires incorporate a "polyurethane foam layer" on the inside of the tread to directly absorb tire noise during driving, a feature not found on standard tires.

Differences in Usage and Lifespan: Adapting to Different Driving Habits

Due to their different performance designs, the applicable scenarios and lifespans of the two tires differ significantly.

Usage Limitations: If standard tires are installed on electric vehicles, insufficient load capacity and excessive rolling resistance will significantly reduce range (possibly by 10%-15%). Long-term use also increases the risk of sidewall bulging and uneven tread wear. Conversely, while electric vehicle tires may offer improved quietness and comfort, they also offer poorer wear resistance and higher long-term operating costs.

Lifespan Difference: Under the same mileage and road conditions, standard tires typically have a lifespan 10,000-20,000 kilometers longer than electric vehicle tires. This is because electric vehicle tires use softer tread rubber to reduce rolling resistance, resulting in relatively weaker wear resistance. Furthermore, the heavy pressure of the battery and high torque of the electric motor accelerate wear of the tread and sidewall.