Aim of this study

The research aims to develop a method for assessing the sustainability of post-lithium battery systems and to investigate possible upscaling of production in the early design phases.

Objectives

While the production of lithium batteries is increasingly dependent on the supply of critical raw materials, post-lithium batteries, such as sodium or magnesium batteries, appear promising, since they are mostly made from abundant earth elements and potentially offer higher energy density and improved sustainability compared to lithium batteries. Therefore, a comprehensive sustainability assessment of the new battery systems is required, considering environmental, economic, and socio-technological aspects. There is much scope for improving sustainability, as these systems are still at early technology readiness levels (TRLs).

Previous research has mainly focused on individual dimensions of sustainability, while neglecting integrative approaches for different types of post-lithium batteries. The present work proposes a comprehensive method to close this gap. This method is used to assess the sustainability of post-lithium materials, components, and prototype cells developed by the POLiS Cluster of Excellence, taking into account ecological, economic, and social aspects. The results will provide technology developers with feedback for improving the systems under investigation. The evaluation is prospective in nature and includes a theoretical upscaling in order to identify unforeseeable effects and sustainability hotspots.

Methodology

The method is applicable to battery systems at different TRLs since the analytical approaches can be adapted to the respective development levels. For low TRLs, qualitative analyses, e.g., resource analyses, are performed on laboratory samples in order to roughly screen the materials from a sustainability perspective. For more mature laboratory-scale battery systems, for which sufficient data is available, a prospective life cycle sustainability assessment can be conducted to comprehensively quantify the environmental, economic, and social impacts of the systems throughout their life cycle.

At the same time, the inputs and outputs are continuously discussed with technology developers, as the input data is initially obtained from the laboratory and then revised based on the intermediate results. In this way, it is possible to identify sustainability hotspots along the potential life cycle and determine scalability with regard to the entire production chain. The outcomes of this work can thus provide decision-making support to technology developers (e.g., in the early screening of alternative materials) and assist them in determining sustainable development paths for post-lithium battery technology.

Expected impacts

The outcome of the economic, ecological, and social analyses will help identify promising development paths for the next generation of battery technology together with battery scientist.