Audi Neckarsulm: More efficient charging infrastructure thanks to second-life storage
The Audi Neckarsulm site is creating 72 additional charging points for electric cars through so-called cubes, which use used lithium-ion batteries as power storage. The second-life batteries come from dismantled Audi test vehicles.
Two of the cubes feed a total of 48 charging points and expand the charging capacity for employees and visitors to the Neckarsulm site in multi-storey car park 1 in the southeast of the Audi plant. A Cube with a further 24 charging points is located in the car park at the northeastern boundary of the plant. The electricity storage units save the car manufacturer from having to set up a cost-intensive infrastructure with medium-voltage supply lines and transformers.
In each of the three cubes, 198 used battery modules with twelve cells each serving as energy storage. The capacity can also be expanded if necessary: There is room for 132 more modules in each of the cubes. Together, the container cubes at the Neckarsulm site store 1.58 MWh of energy. A 70-kW supply line per cube can charge the storage modules overnight.
Employees and visitors can use the cubes for their electric cars via wall boxes with a charging capacity of up to 11 kW each. The buffer from the used lithium-ion batteries cushions any peaks in demand. "Thanks to the batteries in the cubes, we gain 300 kW of charging power for the wall boxes from the relatively low connected load of 70 kW," explains Jannik Marshall, project manager for the expansion of the charging infrastructure at the site. The system works like a rain barrel: the incoming connected load is constantly fed into the energy storage units. In the future, photovoltaic modules could also supply self-generated green energy for the Cubes.
In addition to the new Cubes and the 40 or so charging points in the multi-storey car park at the Audi Forum Neckarsulm, which have already been in use for around two years, Audi has put another 150 charging points into operation in the multi-storey car park 2 on the eastern boundary of the plant - fed by a transformer station. There are now around 600 charging points for e-vehicles on the plant premises and at the Neckarsulm and Heilbronn plant boundaries, of which around 20 are fast charging points. Just like the entire site, they are powered by green electricity. "With our charging points, we are making our site fit for the electrification of our models and also allowing employees to charge their e-cars during working hours," says Alexander Jakob, Head of Plant Structure Planning Neckarsulm. Some of the charging points are also open to the public. This means that e-drivers in the region can also use the service.