ReDesign – Development of design guidelines for the recycling-oriented design of battery systems in context of the circular economy

Currently developed and manufactured lithium-ion battery systems are optimized specifically with focus on performance, energy density and costs. Aspects of a cycle- or recycling-oriented design of cells, modules and systems have so far only been given secondary consideration. In the past, this has led to battery systems usually being dispatched to the recycling process as a whole system at the end of their first life cycle, since removing individual components from the battery system involves a great deal of technical and organizational effort. Also within the recycling process, the constructive and material-technical design of battery systems requires effort, which can be reduced by a cycle-oriented design according to the principles of design-for-recycling. These issues lead to complex, multidimensional requirements for the product design of battery systems, in which a multitude of conflicting goals prevail. The systematic resolution of the conflicting goals requires an ecological and economic evaluation of the product and material flows. Taking into account the structural and procedural characteristics of battery systems, modules and components and the possible paths of the product and material flows, solution approaches for the design of battery systems must be developed and refined into concepts in order to minimize the losses in the product and material cycle (“open loops”). In particular, application requirements and the availability of suitable manufacturing processes as a sink for product and material cycles must be taken into account with regard to possible conflicts of objectives. The objectives of the ReDesign project are derived from this motivation and the associated questions. The overall objective of the project is to increase the recyclability of battery systems in order to avoid “open loops” in the material cycle and to reduce the negative environmental impacts of batteries.

Composition of the quantity shares of the battery components © Marisol Glasserman/TU Braunschweig

This is to be achieved by the systematic development of design guidelines for the cycle-oriented design and recycling-oriented design of battery systems in order to create the prerequisites for a closed, efficient battery system life cycle with low raw material losses. The first step is a system definition and a derivation of optimization targets for the circular economy. Based on disassembly tests and an analysis of the state of the art, a comprehensive analysis and description of constructive design features of current Li-Lion battery systems is carried out. This is followed by a holistic analysis of recycling management options for battery systems during or after end-of-life. A toolbox for the design of recycling-oriented battery systems will be developed, by means of which the aspects of cycle management will be linked with constructive solutions. For this purpose, individual tools will be developed and clustered into a tool box that brings together the identification of design options with their environmental assessment. The results of the tool box will be incorporated into the development of two concept demonstrators for battery cells that illustrate the implementation of recycling-oriented design using a Green Conventional Lithium Battery and a Green Solid State Battery. This is followed by the design of a virtual battery system demonstrator, which is used to visualize solution approaches, improvements and the application of the developed tools. Finally, an Identification will be carried out for the analysis and evaluation of business models to support the recycling of battery systems and a definition of recommendations for action towards the recycling-friendly design of batteries as a basis for the transfer of results to industry as well as for regulatory organizations.