High Power Charging for EV’s
How to innovate mobility with technologically leading products Electromobility is old hat. Even the very first motorized vehicles had an electric motor. The challenge then as now: How can I get as much energy as possible into the mobile energy stores as quickly as possible? As early as 1881, the Frenchman M. Gustave Trouvé presented his sensational tricycle – 12 kilometers per hour fast and quite similar to a stagecoach. With a range of about 14 kilometers, the vehicle was almost suitable for everyday use, because at that time the competition on the long distance was only the horse. Werner Siemens, Andreas Flocken, Ferdinand Porsche – the list of e-pioneers is long and contains amazing names. Between 1896 and 1939 there were 565 different brands of electric cars worldwide. In New York, the share of electric vehicles was 50 percent in 1901. The rest were steam cars or naphtha, acetylene or compressed air driven vehicles. Even Henry Ford developed a Ford Model T with an electric motor, which, however, did not go into series production. What followed was almost 100 years of electric mobility at a standstill. Electromobility takes off At the beginning of the 21st century, several major automobile groups dared to enter the market with electric models – electric vehicles thus received a new development boost and public attention. A good 10 years ago, the subject of e-mobility really took off when the first vehicles with longer ranges were presented. When Phoenix Contact entered the e-mobility market, the initial focus was on individual components. The first customer-specific connectors with combined signal and power transmission for charging electric vehicles were developed in 2009. As early as 2010, AC charging sockets for Chinese charging station manufacturers were built and delivered in large quantities. In 2011, there were applications with large volumes in the commercial vehicle sector. Electric buses in China used heavy connectors to change large batteries. In the depot, the discharged batteries were automatically replaced with charged ones in order to optimise the utilisation of the buses. To this day, heavy connectors for exchangeable batteries are used in Chinese buses. In the early days, electric cars were mostly charged with alternating current. In order to achieve higher charging capacities and shorter charging times, especially in the public sector, it became necessary to standardise a solution for DC charging. Together with leading automotive manufacturers, Phoenix Contact developed and defined a worldwide charging standard for combined AC and DC charging (later Combined Charging System, CCS). CCS proved to be safe, flexible and practicable and in 2014 became the recognised standard for vehicles and public charging infrastructure in the European and American markets. (picture 3) But the demand for faster charging times also for passenger cars became increasingly louder. The first pre-developments took place at the beginning of 2015. Developer Dirk Moseke from Phoenix Contact E-Mobility has accompanied the further development of the CCS standard almost from the very beginning and here he describes in his own words how the next steps proceeded: “Of course, there were also specifications and standards in development. But there was nothing. And that was only two years ago! So we had to develop it ourselves. What do we have to do to get something completely different out of the already existing CCS standard with the defined mating face? 200 amps were no problem, but now 300 amps and more are required. Today we’re at 500 amps. There would be a yellow sign in a building in front of the access to such currents saying “Access prohibited”. And this is where we have to make the facilities freely accessible, exposed to the weather and possible abuses. The first point was the development of suitable cables. With such currents, there are only two possibilities: larger cable cross-sections or significant heating. However, the cable must not become too thick, otherwise it becomes too heavy and stiff. So we have devoted ourselves to the subject of heat generation. The first task was to determine where the heat actually originated. In fact, it’s the wire itself that gets warm. However, the heat can also come from the vehicle, i.e. from a point that we cannot influence at all. The next thought was to cool with liquids. This means to rinse the copper directly with a heat dissipating medium. We rejected an oil-based solution, because it was far too complicated to handle – and anything but innovative. Research and development working side by side Next, we tried air cooling. To do this, we blew air into tubes containing the hot cables. But the air had to go somewhere and then came out in the connector again. In addition, air does not absorb heat so quickly. Our result: Not practical. So we did some more research on alternative coolants and ended up with the easy-to-handle and environmentally friendly glycol. In addition, we have used heat-conducting paste in the cable. This even worked partially, but was not suitable for series production. In the meantime, we had also discovered that it made sense to make the surface as large as possible. More surface area means better heat dissipation. So we did experiments with a lot of single strands. It partly looked as in a knitting room here, with shrink tubing, cable ties and duct tape. Basic research as it can also be found at any university. Today we have a cable that leads two 25 mm2 copper wires twice – two for plus, two for minus. This ensures that the cable is not too heavy but nice and flexible. We have built a layer into the outer sheath that shows when the cable is worn out or damaged. In addition, the cable must not become hotter than 60 degrees so it can be enclosed – according to the standard. This is monitored by sensors and is coupled with a switch-off device. In addition, communication wires run through the cable, which the connector needs in combination with the column. The next challenge was the connector
Charging in record time
A superior technology ensures high power charging in the most convenient and safe way. Super-charged in 15 minutes – how HUBER+SUHNER is accelerating the electric vehicle market Electric vehicles are increasingly becoming the car of choice as more people become environmentally conscious. The sale of electrical vehicles in the US increased by 81% in 2018, with a growing number of charging stations being installed across the US to meet this demand. According to J.P. Morgan, by 2025 electric vehicles are expected to make up a total 30% of all vehicle sales, contributing to a rise of 8.4 million electric vehicles on the road. Yet, when consumers think of purchasing an electric vehicle, one of the biggest concerns is where they will be able to power up, as well as how long it will take. No one wants to be stood by the roadside for hours waiting for their vehicle to charge to continue a journey. However, purchasing a low-emission, fuel-efficient vehicle does not mean consumers have to compromise on performance or convenience. Currently, charging times are often lengthy and disruptive for everyday life as many charging spots offer average outputs of 7-50kW, with a full charge taking up to three hours. When compared to the wait time of eight hours when electric vehicles were first launched, this is progress – but there is still some way to go before the ultimate aim of making charging as quick and easy as filling up with fuel is achieved. Reducing charging time As a result of this, and discussions with various Automotive OEM’s, HUBER+SUHNER, a Swiss-based manufacturer of components and systems for electrical and optical connectivity, has developed an innovative power cable solution to enhance electrical charging stations and reduce charging time. In order to achieve this, higher power must be transmitted through cables for charging electric vehicles. The standard solution would be to just increase the cross section of the cable, but this would lead to a very bulky cable making handling difficult for the majority of consumers. Therefore, to reduce weight and increase flexibility, a cooled cable solution was developed. This solution ensures easy handling at the charging station and can draw up to 500A/1000V, enabling new generation EV cars to charge in just 10-15 minutes to 80% state of charge. Dubbed the RADOX® HPC, the system has been developed to be flexible, easy to handle and lightweight, enabling even higher ratings to ensure it is future-proof. The upward compatible and customisable system helps the utility provider to be prepared for future needs and, as a result, secure vital investments. As providing a solution with 500A in public use is new, safety and reliability were given the highest priority in the development phase. Additionally, the product is approved in accordance with European and American standards. Accelerating the electric vehicle market To enable a successful market introduction of the new generation of EV cars, an HPC infrastructure is required. With the ability to charge an electric vehicle in less than 15 minutes from a convenient station and enough power to last for hundreds of kilometres, we believe it now makes sense for motorists to switch to electric cars as their favoured method of transport. The state-of-the-art infrastructure will not only make lives easier and safer, but with the addition of more charging points with the RADOX® HPC system implemented around the world, charging an electric car away from home is now simple and convenient. The product is already in serial production, with various roll-out programmes currently running in the US and Europe. We hope Asia will also follow soon. To bring more advanced and adaptable electrical cars successfully into the market, a solid network of charging stations is also required. Along with the existing standard charging points for electric cars at home, work and in car parks, a new generation of high-power charging points along main travel routes are being implemented to ensure drivers are not restricted, with experts suggesting that the worldwide number of public charging points will increase to approximately 40 million in 2030. HUBER+SUHNER is currently playing an integral role in the development of these stations by supplying the cooled cables to Electrify America. Electrify America is a Volkswagen subsidiary set up as part of the diesel emissions test settlement to develop a network of electric charging stations across the U.S. In the next two years, Electrify America will install a highway network of ultra-fast Direct Current Fast Charge stations. This will include building new sites which will connect regional destinations and filling in existing routes as station utilization of the highway network increases. This project will continue to see HUBER+SUHNER play a vital role in developing the infrastructure needed to make electric vehicles a reality for consumers across America. With projects such as this one, we are confident consumers will continue to increasingly choose electric vehicles, meeting and even exceeding the ambitions of the electric vehicle market. By Max Göldi, Market Manager at HUBER+SUHNER
