Putting electric vehicle charging to a high-temp test

Whether in your phone, your watch or a next-generation electric vehicle, batteries can respond differently to temperature extremes. And when you’re about to build millions of electric vehicles worldwide, engineers want to research what could happen when plugging an EV into a 350-kW DC fast charger on the hottest days.1

That’s why Volkswagen Group has spent the past year building one of the most advanced EV charging test sites in the world at the Arizona Proving Grounds. The 50 charging stations feature a mix of standards and power levels from around the world, designed to test how electric systems handle recharging at desert temperatures that can reach 120 degrees Fahrenheit.

It’s a key building block in Volkswagen Group’s goal to become carbon neutral across its business by 2050, and its goal of building about 20 million electric vehicles worldwide by 2029, including the upcoming ID.4 electric SUV that will debut on Sept. 23. Already, the site has led to an innovation for electric vehicles – a battery cooling system designed to help prevent overheating damage to batteries in emergency situations. It’s based on the technology used at the site to monitor the temperature of battery cells as they charge.

“The opening of this  facility means one of the most sophisticated EV testing facilities in the world, with some of the toughest conditions on earth, will be right here in the United States,” said Dr. Wolfgang Demmelbauer-Ebner, Chief Engineering Officer for Volkswagen’s North American Region. “It reaffirms not only Volkswagen’s commitment to the U.S. market as we bolster our engineering expertise here but also our drive towards an electric future.”

If you’ve ever traveled overseas, you know that every country has a slightly different set of plugs and electric voltages for home appliances. Electric vehicles have to be designed to handle one of three international standards for plugs and a sizable range of power inputs, from a typical 120-volt U.S. wall outlet up to the fast chargers that employ industrial-grade electric currents.

The Arizona Proving Ground site includes 25 DC fast chargers running at currents from the most common 50 kW output up to the 350 kW envisioned by Volkswagen Group’s most exclusive electric sports cars, along with 10 Level 2 AC chargers that simulate home charging. The chargers will utilize charge plugs from the three standard connector types: U.S. (CCS1), Europe (CCS2) and China (GB-T), along with equipment from different brands from around the world to optimize testing variability.

The 16 parking spots were built with a remote-controlled canopy that can vary the level of sun or shade needed for testing. The station is also designed with the future in mind, as technologies such as inductive charging continue to be developed.

The 1,600-acre Arizona Proving Grounds opened in 1993 and supports testing of vehicle durability, corrosion, weathering and severe hot-weather endurance for Volkswagen Group products worldwide including the Audi, Porsche, Lamborghini, Bentley and Volkswagen brands.