Kia has been testing the success of its design changes to enable its latest electric vehicle range to suit harsh winter driving conditions
Even as the summer months reach their height, engineers in the automotive industry are pursuing their aims of consistent reliability of the new generation of electric vehicles in the most demanding conditions, even during the winter months in the world’s coldest climates.
One manufacturer, Kia has paid close attention to the design of its EV9 vehicle and has made modifications to the way it has been constructed in order to ensure it isn’t adversely affected by harsh climatic conditions.
During winter testing in Arjeplog, Sweden, under bitterly sub-zero temperature conditions near the polar circle, Kia engineers tested the new EV9 to ensure optimal battery and charging performance, despite the extreme low temperature. In addition, they optimised the Traction Control System for the best possible performance when driving on snow and ice.
According to Gunther Frank, General Manager Development Project Operations at Hyundai Motor Europe Technical Centre (HMETC), it’s a myth that EVs aren’t good to drive in the snow and the centre’s object was to prove that the technology exists to overcome charging speed challenges in cold-weather conditions, as well as the ride and handling improvements to make an EV safe and even fun to drive in the snow.
Charging performance optimisation
Under optimal conditions, the Kia EV9 has an all-electric target driving range of over 541 km, according to the World harmonised Light vehicle Testing Procedure (WLTP). With 800-volt ultra-fast charging, it can gain up to 239km in range after just 15 minutes of charging. As with all EVs, however, driving in extreme heat or extreme cold can result in slower charging and shorter driving ranges.
“Like the human body, a battery also has a certain temperature range where it feels most comfortable. Within this range, it can provide its best performance while driving and charging. Outside that range, dedicated, state-of-the-art battery thermal technologies have been implemented to manage these extreme conditions,” says Frank.
One of these features is battery conditioning, which was first introduced with the Kia EV6. Battery conditioning essentially means pre-heating the battery before charging. By achieving optimal battery temperature before charging begins, the EV9 can continue to achieve ultra-fast charging, despite the cold.
The “EV Route Planner” has also been introduced for the first time on the EV9, providing drivers with the convenience of automatically programming charging points into the route when they are needed. The system analyses real-time vehicle data, as well as the route that has been entered into the AVN system, to add charging points when needed. When the estimated all-electric driving range is insufficient to reach the destination, the AVN displays a pop-up suggesting possible charging stations and asking the driver if they would like to add it to the route. This means they don’t need to spend time planning out their routes based on the availability of charging stations – the EV9 does it for them by showing them when, where, and for how long to charge.
EV Route Planner and battery conditioning work together to pre-heat the battery in cold conditions when a high-speed charging point is coming up. “Our target is to provide the best possible driving and charging experience to our customers. We want them to be able to drive longer distances in the shortest possible time and in the most relaxed way to make the step from ICE to EV cars as easy and smooth as possible,” says Frank.
The low centre of gravity and long wheelbase of the Kia EV9 help stabilise the vehicle while driving – specifically, by reducing roll on corners. To cope with the additional weight and increased acceleration associated with EVs, the engineers expanded the front brake discs. Additionally, the Kia EV9’s regenerative braking system has been improved by applying a second-generation Integrated Electric Booster, or IEB, to reduce the overall weight and improve energy efficiency.
The EV9’s chassis has been optimised, and the suspension has been tuned, to ensure excellent handling capabilities on snow and ice. The engineers aimed to find the right mix between safe and smooth handling and responsiveness and being fun to drive. The result is an overall more balanced driving experience focused on delivering maximum passenger comfort, regardless of driving conditions, according to Kia.
For its testing on the Arjeplog testing ground in Sweden, the EV9 was equipped by HMETC with dedicated winter tyres, which provide maximum stability on the snow tracks. Overall, tyre choice will be an important factor in winter conditions as well as the choice of wheel, available in 19, 20 or 21 inch variants.
Another feature to improve handling on snow and ice is all-wheel drive. The all-wheel drive variant of the EV9 features both front and rear electric motors. The RWD model utilises a 150 kW electric motor, and the AWD features a total power output of 283 kW. This essentially doubles the system power when AWD is activated.
Snow Mode Control
The Kia EV9’s Traction Control System, or TCS, is meant to improve performance when driving in challenging terrain. Drivers can choose between Mud, Sand and Snow modes by using the Terrain Mode Select button on the steering wheel to optimise driving performance for different conditions. The system adjusts motor torque output and distribution as well as the chassis systems and other stability control characteristics to ensure safe performance, even in low-grip conditions.
Snow mode is optimised to maintain stability and forward momentum in slippery conditions. When Snow mode is activated, the traction control system limits torque output from the motors and controls them for optimum tyre grip on all four wheels to maintain the momentum. This concept also applies the braking control system in order to optimise traction.
The EV9 will be the higher end SUV in the Kia range, one that will consist of 15 electric models available by 2027. Kia predicts that EV sales will reach 1.6 million units per year by 2030.