High-voltage batteries from discarded electric cars can still be put to good use even after years of use on the road. AUDI and EnBW Energie Baden-Württemberg AG are now using this in ajoint project with stationary battery storage systemfor so-called Second Life batteries, which come from disassembled test vehicles from Audi test vehicles. The plant is intended to store electricity from renewable energies, compensate for fluctuations in the power grid and thus contribute to security of supply and have officially commissioned the pilot plant on EnBW's power plant site in Heilbronn. High-performance lithium-ion batteries are an important building block both for the transport transition and for the design of a sustainable energy supply. When an electric car has reached the end of its use, its battery cells are by no means unusable, but in some cases still has a high proportion of their original performance. In a second life, they can still be put to good use for the purpose for which they were built – to store electricity. The new battery storage system in Heilbronn consists of twelve high-voltage battery systems that come from disassembled development vehicles. Interconnected, they have a total output of one megawatt– so the ready-to-use storage system could cover the electricity consumption of around 3,000 households for about an hour. The special feature of it is a "plug & play" approach, with which the vehicle batteries can be easily and thus very cost-effectively interconnected to form a storage system. The plant will initially serve as a reference for four projects that EnBW is currently planning for the near future.