EV Tires: Advancement Achieved Through Testing | Hankook Tire Global official site

Almost all automakers on the planet are promoting electrification as their most crucial goal of mid-to-long term roadmaps. At one point, internal combustion engines and electric motors were expected to maintain their parallel status for a while, like "two families under one roof." However, unlike the speculation of a decade ago, EVs rapidly push internal combustion engines into the past. In other words, the automobile paradigm has transformed.

The tire is the most critical factor for driving, rolling, and coming to a complete stop. It is common sense that there are differences between the comfort tires and sport tires, depending on the vehicle type and environment. The effectiveness of all-season tires and winter tires differs by context, and urban tires and off-road tires work differently in changing environments, even when installed on the same SUV. EV drivers who experienced these coming trends before anybody else agree that dedicated EV tires are now essential.

Electrification is a concern of all companies directly or indirectly involved in making and driving vehicles.

The people whose job is to test tires dedicated to EVs are former race drivers who possess the ability to push the tires to their limits on motorsports tracks. They now spend more time with EVs than anyone else to understand and develop an ideal EV tire. We met and spoke with the EV test drivers from the VEP team at Hankook Tire to learn more about EV-dedicated tires.

Interview

Sungyeon Park and Jongjin Park (Hankook Tire Test drivers)

Hankook Tire & Technology-Technology in Motion-EV Tires advancement achieved through testing-2

©Park Namkyu

Q. How much driving do test drivers do on average? Are the tests conducted by the drivers alone?

I drive about 200 km a day. And I sit in a car for 4 to 5 hours every day. Usually, the test drive is conducted by one main evaluator, that is, the driver alone. In critical, equipment-required, or specific situations, a researcher may accompany the driver in a two-person evaluation.

©Park Namkyu

Q. What is the difference from the driver's point of view when testing internal combustion engine tires and EV tires?

Due to the characteristics of EVs, ride comfort and handling performances are evaluated closely during the EV tire tests. The other fundamental processes of testing are the same as any regular tires. EV tires are also released in various segments, and the items that focus on testing may slightly differ by model. For example, tires that have been developed for the sports segment model cars prioritize handling, grip, and braking, while the tires of the comfort segment model value riding comfort and quietness.

“We test the EV-dedicated tires every day and strive to push almost all the performance factors required for tires to a higher level.

Tire development, such as human civilization, is always ‘present progressive.’ We are always aiming higher.”

Q. Among the numerous EVs, which models from which brands have chosen Hankook Tire as the tires for an OE shipment?

Four models from three brands, Porsche Taycan, Audi e-Tron, Q4 e-Tron, Volkswagen ID.4, chose EV-dedicated tires made by Hankook Tire, and we expect this trend will continue.

Porsche Taycan, Audi e-Tron, Q4 e-Tron, and Volkswagen ID.4 are equipped and shipped with the EV-dedicated tires manufactured by Hankook Tire.

Hankook Tire Ventus S1 Evo3 for EVs applied technologies such as a new compound with low rolling resistance, an interlocking groove improved by the wet road performance, noise reduction pattern, and sound-absorbing material.

Q. What is the difference between the tires for internal combustion engine cars and for EVs? Are any parts being developed with particular attention to the EV tires?

The EVs have more weight because of the required larger battery capacity with models with a more extended range. The EV tires tend to be harder to support the added weight, making the ride a bit harsher. Additionally, EV tires have a disadvantage over the internal combustion engines in terms of wear. The noise levels of the electric motors are much lower, making the road noise more noticeable. These are why EV-dedicated tires generally require a higher level of performance.

We have continuously developed sound absorbers and lower-noise tread patterns specific to tires for EVs to address these issues. However, the difficulty in developing tires for EVs arises as conflict amongst the performances that we want to improve. For example, if the wear resistance is improved, that comes at the cost of the water discharging performance or the grip. However, we could not compromise this exchange of equivalents. Satisfying both is easier said than done, but based on the company's judgment that it can preempt the premium market only by developing top-notch tires, we are heavily concentrating on research and testing at a company-wide level.

Hankook Tire & Technology-Technology in Motion-EV Tires advancement achieved through testing-9

©Park Namkyu

“EV-dedicated tires allow you to experience excellent efficiency and an excellent exercise performance, in the exact way the EV was originally designed.

We are also contributing to the development of EV-dedicated tires by conducting repeated tests.”

EV tire film_The Quietness

Q. What is the goal of the EV tire, set by Hankook Tire itself?

The basis of developing OE tires is to satisfy the performance needs required for the model according to each of the vehicle's characteristics. Although the performance criteria required by the manufacturer may vary, we are delivering to their needs. For the EV market that is rapidly changing, we are doing our part to be nimble to respond to that change.

While the smaller and efficient electric vehicles, such as Nissan Leaf, BMW i3, and Toyota Prius, were mainstream, high-performance models such as the Porsche Taycan gained more popularity. As SUVs have become popular worldwide, the majority of newly released vehicles in the EV market may become SUVs, too. Looking at the Tesla Model S as an example, this trend of premium and larger vehicles will continue. So, EV types have become as diverse as the combustion engine vehicles. Rather than setting our own standards or goals, we must realize the best performance required for EV tires at all levels.

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