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The recycling of lithium-ion batteries, in particular, has become increasingly important in recent years. Due to the materials contained, such as copper or nickel, the return to the economic cycle is important. To ensure this, binding measures have been introduced by the European Commission. As part of the mechanical recycling of lithium-ion batteries, the zig-zag air classifier is used to separate battery components. One application is the separation of the current conductor foils from each other, which is investigated and modelled here. Existing models deriving from the literature are evaluated for material fractions coming from the recycling of different automotive lithium-ion batteries. Since the separation depends on the geometry of the foil particles, similarities for separation depending on the geometric characteristics of the electrodes are derived. It turns out that the material is too complex for the empirical model. However, the model can be used to evaluate the suitability of the apparatus and the quality of the separation.

Considering the increasing demand for Li-ion batteries, there is a need for sophisticated recycling strategies with both high recovery rates and low costs. Applying optical sensors for automating component detection is a very promising approach because of the non-contact, real-time process monitoring and the potential for complete digitization of mechanical sorting processes. In this work, mm-scale particles from shredded end-of-life Li-ion batteries are investigated by five different reflectance sensors, and a range from the visible to long-wave infrared is covered to determine the ideal detection window for major component identification as relevant input signals to sorting technologies. Based on the characterization, a spectral library including Al, Cu, separator foil, inlay foil, and plastic splinters was created, and the visible to near-infrared range (400–1000 nm) was identified as the most suitable spectral range to reliably discriminate between Al, Cu, and other battery components in the recycling material stream of interest. The evaluation of the different sensor types outlines that only imaging sensors meet the requirements of recycling stream monitoring and can deliver sufficient signal quality for subsequent mechanical sorting controls. Requirements for the setup parameters were discussed leading to the setup recommendation of a fast snapshot camera with a sufficiently high spectral resolution and signal-to-noise ratio.

Lithium-Ion Battery (LIB) manufacturers produce different cell formats (prismatic, cylindrical, pouch, etc.) with different casing materials (steel or aluminium) and cell chemistries (e.g., NMC, NCA, LFP, etc.) for application in electric vehicles. By law, these cells have to be recycled after their lifetime. This study investigates the influence of different cell types on the outcome of a standardized mechanical recycling process consisting of crushing, sieving and air classification. The aim of the study is to find out whether different cell types can be processed together or whether the recovery and product quality can be improved by processing them separately. Pouch cells require low energy consumption for crushing compared to cylindrical and prismatic cells. Steel as a casing material increases the energy requirement during crushing compared to aluminium. The particle size distribution of several product fractions varies significantly between the different cell types. During air classification, the separator, anode, and cathode show a similar separation behaviour and can be processed with the same settings, whereas for the separation of the casing metals, different settling velocities need to be applied depending on the casing material.

With the increasing number of electric vehicles (EVs) rises the need to recycle their used lithium-ion batteries (LIBs). During the mechanical process of the recycling of the LIB cells, a fine fraction, the so-called black mass, is created. This black mass consists mostly of the coatings originating from the cells’ electrodes and residues from the electrolyte, together with a low amount of Al and Cu from the crushed current collector foils. The amount of black mass as well as its composition is influenced by the chosen grid size at the crusher discharge. To reduce solvent emissions during the recycling process, a thermal pre-treatment can be added before crushing, which also influences the black mass and its properties due to changes in the adhesion between electrode foils and coating. This study investigates the influence of the crusher settings as well as the pre-treatment temperatures to find an optimum between the recovery of the coating and conductive salt, while limiting the amount of Al and Cu in the black mass.

With the increasing number of electrical devices, especially electric vehicles, the need for efficient recycling processes of electric components is on the rise. Mechanical recycling of lithium-ion batteries includes the comminution of the electrodes and sorting the particle mixtures to achieve the highest possible purities of the individual material components (e.g., copper and aluminum). An important part of recycling is the quantitative determination of the yield and recovery rate, which is required to adapt the processes to different feed materials. Since this is usually done by sorting individual particles manually before determining the mass of each material, we developed a novel method for automating this evaluation process. The method is based on detecting the different material particles in images based on simple thresholding techniques and analyzing the correlation of the area of each material in the field of view to the mass in the previously prepared samples. This can then be applied to further samples to determine their mass composition. Using this automated method, the process is accelerated, the accuracy is improved compared to a human operator, and the cost of the evaluation process is reduced.

Cementitious composite that has short molding time and high mechanical performance is favorable in pre-cast concrete industry. In this context, this study reports the use of hot-pressing technique to fabricate PVA fiber reinforced composites using alkali-activated stone wool (a waste from building insulation). Eight different mixtures were developed by varying the pressing time and temperature in comparison to the conventional oven-cured alkali-activated material. The mechanical performance of all compositions was evaluated under bending and compressive loadings. Life cycle assessment was used to investigate the greenhouse gas emission and embodied energy of the developed composites. The results reveal that PVA fibers greatly enhanced the mechanical performance of all reinforced mixtures with deflection hardening behavior and improvement in compressive strength. The hot-pressing technique lowered CO2 emission and saved energy. Finally, a multi-criteria ranking method suggests hot-pressed PVA fiber reinforced cementitious composite, manufactured at 120 °C for 2 h, is the best composition attaining balance among energy spent, mechanical properties, and CO2 footprint. Keywords: Hot-pressing, Alkali-activated material, High performance cementitious composite, Mineral wool, Recycling

In the realm of global health policy, the intricacies of power dynamics and intersectionality have become increasingly evident. Structurally embedded power hierarchies constitute a significant concern in achieving health for all and demand transformational change. Adopting intersectional feminist approaches potentially mitigates health inequities through more inclusive and responsive health policies. While feminist approaches to foreign and development policies are receiving increasing attention, they are not accorded the importance they deserve in global health policy. This article presents a framework for a Feminist Global Health Policy (FGHP), outlines the objectives and underlying principles and identifies the actors responsible for its meaningful implementation. Recognising that power hierarchies and societal contexts inherently shape research, the proposed framework was developed via a participatory research approach that aligns with feminist principles. Three independent online focus groups were conducted between August and September 2022 with 11 participants affiliated to the global-academic or local-activist level and covering all WHO regions. The qualitative content analysis revealed that a FGHP must be centred on considerations of intersectionality, power and knowledge paradigms to present meaningful alternatives to the current structures. By balancing guiding principles with sensitivity for context-specific adaptations, the framework is designed to be applicable locally and globally, whilst its adoption is intended to advance health equity and reproductive justice, with communities and policymakers identified as the main actors. This study underscores the importance of dismantling power structures by fostering intersectional and participatory approaches for a more equitable global health landscape. The FGHP framework is intended to initiate debate among global health practitioners, policymakers, researchers and communities. Whilst an undeniably intricate and time-consuming process, continuous and collaborative work towards health equity is imperative to translate this vision into practice.

The complexity of crisis management in the context of COVID-19, which ranges from the global to the national, reveals a wide variety of means and ends, particularly at the national level. This triggered scholarly interest and raised questions regarding how central (authoritarian) governments handle the COVID-19 pandemic within state borders. The paper evaluates the Thai government's response to the COVID-19 pandemic from the beginning of 2020 to the middle of 2022, when the pandemic was declared over. We employ critical discourse analysis to explain Thailand's crisis management by engaging discursively with different population groups in the country. The findings indicate that the discursive policies and measures implemented by the government to deviate from and halt public pressure resulting from his mismanagement of vaccine policy are based on narratives related to national traditions as a means of resolving dilemmas rather than on the social needs of vulnerable individual citizens. We witnessed how discursive policies and measures can lead to other problems and ineffective responses, specifically regarding vaccine distribution. The article contributes to a better understanding of how, why, and to what extent discursive policies and measures were instrumentalized by an authoritarian government for COVID-19 crisis management, which can likely be inferred in similar cases in developing nations.