An efficient network of charging points is one of the basic infrastructural prerequisites for convincing customers to buy electric vehicles. Using the 100-kW dc fast-charging station, a Volkswagen ID. family EV could be charged in as little as 17 minutes.
By Murray Slovick, Contributing Editor
To celebrate the New Year, Volkswagen offered a glimpse of a future mobile quick-charging station that can be set up flexibly and independent of the power supply wherever it’s needed (Fig. 1). Places include public parking lots, on company premises, or as a temporary charging point at large-scale events.
The mobile charging station works by using the principle of a power bank, which is familiar to people with smartphones, but on a larger scale. Its charging capacity of up to 360 kWh enables up to 15 EVs, including members of Volkswagen’s new ID. family, to be charged in standalone operation. The ID. series comprises electric cars that will cover a distance of 400 to 600 km on a single battery charge.
The first production version of the ID. series is due to be launched in 2020 at a price “on a par with comparably powerful and well-equipped Golf,” according to the company (Fig. 2). Using the 100-kW dc fast-charger, an ID. family car could be charged in as little as 17 minutes, again according to Volkswagen.
If the energy content of the charging station’s integrated battery set is less than 20%, the depleted charging station is simply exchanged for a charged one. If, however, it’s permanently attached to the power supply with up to 30 kW via ac, the battery pack will perpetually recharge itself.
The first mobile quick-charging stations will be set up as early as the first half of 2019 in Volkswagen’s hometown of Wolfsburg, Germany, as part of a pilot project, and will support the expansion of a charging infrastructure in the urban area. In 2020, the charging station will also be implemented in other cities and communities.
“The mobile charging stations are a decisive step toward an efficient network of charging points. They can be set up anywhere as required—with or without connection to the power supply,” said Thomas Schmall, Chairman of the Board of Management of Volkswagen Group Components. “This flexibility enables a completely new approach for the rapid expansion of the charging infrastructure. Cities can, for example, find out the most suitable places for a permanent charging point before making major investments in developing the network. In addition, it will be possible to set up a large number of charging stations temporarily—exactly when and where they are needed.”
These flexible locations could be easily found via the internet or a software app. In addition to electric cars, e-bikes can also be charged. Up to four vehicles are able to be charged simultaneously: two with dc and two with ac connections. The total battery storage capacity of up to 360 kWh is sufficient for up to 15 e-vehicles.
Connect Direct to the Power Supply
There’s also the possibility of directly connecting to the power supply, allowing the station to be charged with up to 30 kW via alternating current by means of a permanent standard grid connection. This enables charging points for EVs to be set up quickly and simply, without any structural changes or major financial outlay.
The direct power connection also allows the battery pack in the charging station to be recharged around the clock. This time-independent recharging, and therefore buffering of power, also considerably reduces the strain on the power supply at peak periods.
“Our mobile charging stations offer a further crucial advantage,” said Mark Möller, Head of Technical Development at Volkswagen Group Components. “It is only when an electric car is charged with sustainably generated power that it can claim CO2-neutral mobility. Our charging station is the first to offer the possibility of temporarily storing sustainably generated power.” He cited the example of a station powered specifically by solar or wind energy, which is then transmitted to the electric vehicles during charging.
The mobile charging column is based on the battery pack of the Volkswagen Group’s Modular Electric Toolkit (MEB) (Fig. 3). This platform will be adaptable to a wide variety of Volkswagen Group vehicles, regardless of vehicle size and performance parameters.
The mobile charging station is an in-house development of the Volkswagen Components Division, which, as of January 1, is now an independent business unit within the Volkswagen Group.