Evolving Critical Metal Systems: Hype Cycles and Implications for Sustainable Innovation

To achieve the transition to sustainable energy and mobility systems, we are relying heavily on critical metals. The sustainable extraction, use, and circulation of these materials is not straightforward as contestation over the social and ecological sustainability of these metals is characterised by so-called hype cycles of increased and decreased legitimacy. This impedes the energy and mobility transition. We propose and apply a novel approach using event graphs to assess critical metal systems as evolving socio-material systems, comparing three longitudinal cases (lithium, cobalt, tantalum). Our analysis leads to an ideal type hype cycle for critical metal systems. Our findings evidence the necessity for policymakers and industry practitioners to use approaches such as responsible innovation to ensure that the extraction, use, and circulation of critical metals does not undermine the transition to sustainable mobility and energy systems.