Audi and EnBW launch the Second Life project

High-voltage batteries from discarded electric cars can still be put to good use even after years of use on the road. Car manufacturer Audi and energy supplier EnBW Energie Baden-Württemberg are now exploiting this potential in a joint project. The system is intended to store electricity from renewable energies, compensate for fluctuations in the power grid and thus contribute to the security of supply. 

The new battery storage system in Heilbronn consists of twelve high-voltage battery systems taken from disassembled development vehicles. Connected together, they have a total output of one megawatt (MW) - which means that the storage system, which is ready for immediate use, could cover the electricity consumption of around 3,000 households for about one hour. What is special about 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 system serves as a reference for initially four projects that are currently planned at EnBW for the near future.

Compared to their first life, the HV batteries are used with significantly lower and more even currents in the second life application. The stresses are thus significantly lower than in mobile use, where a lot of energy has to flow very quickly for acceleration. Those responsible for the project, therefore, assume an operating time of at least five to ten years for the second life of the cells. After that, Audi will finally recycle the batteries. In the process, they are broken down into their individual components and raw materials so that they can be used again in new batteries in the future.