Challenges and prospects of automated disassembly of fuel cells for a circular economy

The hydrogen economy is driven by the growing share of renewable energy and electrification of the transportation sector. The essential components of a hydrogen economy are fuel cells and electrolysis systems. The scarcity of the resources to build these components and the negative environmental impact of their mining requires a circular economy. Concerning disassembly, economical, ergonomic, and safety reasons make a higher degree of automation necessary. Our work outlines the challenges and prospects on automated disassembly of fuel cell stacks. This is carried out by summarizing the state-of-the-art approaches in disassembly and conducting manual non-/destructive disassembly experiments of end-of-life fuel cell stacks. Based on that, a chemical and mechanical analysis of the fuel cell components is performed. From this, an automation potential for the disassembly processes is derived and possible disassembly process routes are modeled. Moreover, recommendations are given regarding disassembly system requirements using a morphological box

Multi-fiber reinforced ettringite-based composites from industrial side streams

Abstract The development of high-performance cementitious composites from industrial side streams, which has both economic and environmental benefits, is of high demand. Ladle slag is a promising by-product from the steelmaking industry, which can form an ettringite-based binder. This experimental investigation focuses on the mechanical properties of different hybrid and mono fibers reinforced by ettringite-based binders from the ladle slag. The experimental results reveal that fibers greatly enhance the mechanical properties of the developed mixtures. The composites exhibit strain-hardening behavior with multiple cracks under flexural and tensile loading. In addition, the compressive strength of the composites can be 130% higher than the plain materials. To attain a balance between mechanical and economic aspects, a multi-criteria ranking method was used to evaluate 12 different mixtures. The ranking method suggests that a polypropylene micro fiber reinforced composite is the best mixture. The study recommends the efficient use of this industrial by-product for valuable applications in the construction industry