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Efficient discharge of Lithium-ion Batteries (LIBs) ensures safe recycling. Electrochemical discharge commonly uses NaCl solutions, causing severe corrosion of battery casing and a release of hazardous gases. This work proposes a novel setup to explore a gaseous product formation during electrochemical discharge processes with low gas quantities, in non-corrosive carbonates solutions (Na2CO3 and K2CO3). Two discharge setups were tested over 120 h: a conventional setup with a single battery completely immersed in the electrolyte; and a novel half-cells setup with two batteries in series, connected through a platinum wire, and partially immersed in the electrolyte. The two setups showed consistent discharge curves and pH trends, without corrosion. After 70 h, the residual voltage of new LIBs (3.8 V) dropped below the safety threshold (2V, 45 ± 1 % of initial voltage for Na2CO3 and 50 % ± 1 % for K2CO3). H2 production was observed during the first 11 h for Na2CO3 (1722 ± 400 ppm/h) and 9 h for K2CO3 (1519 ± 670 ppm/h), with peaks at 2000–2300 ppm/h after 3–5 h while O2 and CO2 production was below the detection limit of the detector (0.1 %-vol for O2, 50 ppm for CO2). pH trends in the aqueous electrolytes (pH increased from 11.5 to 11.6 to 12.5 ± 0.48 pH units after 3 h in Na2CO3, and 12.06 ± 0.06 after 4 h in K2CO3) matched H2 production and the formulation of the hydroxyl ions. The half-cell setup confirmed that H2 release at negative half-cell, increasing the pH of discharge solution. These results presented a safe method for LIBs discharge, avoiding corrosion and hazardous gases release.

Efficient discharge of Lithium-ion Batteries (LIBs) ensures safe recycling. Electrochemical discharge commonly uses NaCl solutions, causing severe corrosion of battery casing and a release of hazardous gases. This work proposes a novel setup to explore a gaseous product formation during electrochemical discharge processes with low gas quantities, in non-corrosive carbonates solutions (Na2CO3 and K2CO3). Two discharge setups were tested over 120 h: a conventional setup with a single battery completely immersed in the electrolyte; and a novel half-cells setup with two batteries in series, connected through a platinum wire, and partially immersed in the electrolyte. The two setups showed consistent discharge curves and pH trends, without corrosion. After 70 h, the residual voltage of new LIBs (3.8 V) dropped below the safety threshold (2V, 45 ± 1 % of initial voltage for Na2CO3 and 50 % ± 1 % for K2CO3). H2 production was observed during the first 11 h for Na2CO3 (1722 ± 400 ppm/h) and 9 h for K2CO3 (1519 ± 670 ppm/h), with peaks at 2000–2300 ppm/h after 3–5 h while O2 and CO2 production was below the detection limit of the detector (0.1 %-vol for O2, 50 ppm for CO2). pH trends in the aqueous electrolytes (pH increased from 11.5 to 11.6 to 12.5 ± 0.48 pH units after 3 h in Na2CO3, and 12.06 ± 0.06 after 4 h in K2CO3) matched H2 production and the formulation of the hydroxyl ions. The half-cell setup confirmed that H2 release at negative half-cell, increasing the pH of discharge solution. These results presented a safe method for LIBs discharge, avoiding corrosion and hazardous gases release.

In this paper, we introduce an innovative framework for the strategic planning of electric vehicle (EV) charging infrastructure within interconnected energy-transportation networks. By harnessing the small-world network model and the advanced optimization capabilities of the Non-dominated Sorting Genetic Algorithm III (NSGA-III), we address the complex challenges of station placement and network design. Our application of the small-world theory ensures that charging stations are optimally interconnected, fostering network resilience and ensuring consistent service availability. We approach the infrastructure planning as a multi-objective optimization task with NSGA-III, focusing on cost minimization and the enhancement of network resilience and connectivity. Through simulations and empirical case studies, we demonstrate the efficacy of our model, which markedly improves the reliability and operational efficiency of EV charging networks. The findings of this study significantly advance the integrated planning and operation of energy and transportation networks, offering insightful contributions to the domain of sustainable urban mobility. Peer reviewed

In this paper, we introduce an innovative framework for the strategic planning of electric vehicle (EV) charging infrastructure within interconnected energy-transportation networks. By harnessing the small-world network model and the advanced optimization capabilities of the Non-dominated Sorting Genetic Algorithm III (NSGA-III), we address the complex challenges of station placement and network design. Our application of the small-world theory ensures that charging stations are optimally interconnected, fostering network resilience and ensuring consistent service availability. We approach the infrastructure planning as a multi-objective optimization task with NSGA-III, focusing on cost minimization and the enhancement of network resilience and connectivity. Through simulations and empirical case studies, we demonstrate the efficacy of our model, which markedly improves the reliability and operational efficiency of EV charging networks. The findings of this study significantly advance the integrated planning and operation of energy and transportation networks, offering insightful contributions to the domain of sustainable urban mobility. Peer reviewed

Li-ion batteries (LIBs) are one of the most deployed energy storage technologies worldwide, providing power for a wide range of applications—from portable electronic devices to electric vehicles (EVs). The growing demand for LIBs, coupled with a shortage of critical battery materials, has prompted the scientific community to seek ways to improve material utilization through the recycling of end-of-life LIBs. While valuable battery metals are already being recycled on an industrial scale, graphite—a material classified as a critical resource—continues to be discarded. In this study, graphite waste recovered from the recycling of LIBs was successfully upcycled into an active graphite/rGO (reduced graphene oxide) composite oxygen electrocatalyst. The precursor graphite for rGO synthesis was also extracted from LIBs. Incorporating rGO into the graphite significantly enhanced the specific surface area and porosity of the resulting composite, facilitating effective doping with residual metals during subsequent nitrogen doping via pyrolysis. These composite catalysts enhanced both the oxygen reduction and oxygen evolution reactions, enabling their use as air electrode catalyst materials in zinc–air batteries (ZABs). The best-performing composite catalyst demonstrated an impressive power density of 100 mW cm−2 and exceptional cycling stability for 137 h. This research further demonstrates the utilization of waste fractions from LIB recycling to drive advancements in energy conversion technologies.

Li-ion batteries (LIBs) are one of the most deployed energy storage technologies worldwide, providing power for a wide range of applications—from portable electronic devices to electric vehicles (EVs). The growing demand for LIBs, coupled with a shortage of critical battery materials, has prompted the scientific community to seek ways to improve material utilization through the recycling of end-of-life LIBs. While valuable battery metals are already being recycled on an industrial scale, graphite—a material classified as a critical resource—continues to be discarded. In this study, graphite waste recovered from the recycling of LIBs was successfully upcycled into an active graphite/rGO (reduced graphene oxide) composite oxygen electrocatalyst. The precursor graphite for rGO synthesis was also extracted from LIBs. Incorporating rGO into the graphite significantly enhanced the specific surface area and porosity of the resulting composite, facilitating effective doping with residual metals during subsequent nitrogen doping via pyrolysis. These composite catalysts enhanced both the oxygen reduction and oxygen evolution reactions, enabling their use as air electrode catalyst materials in zinc–air batteries (ZABs). The best-performing composite catalyst demonstrated an impressive power density of 100 mW cm−2 and exceptional cycling stability for 137 h. This research further demonstrates the utilization of waste fractions from LIB recycling to drive advancements in energy conversion technologies.

Publisher Copyright: © 2024 The Authors Ammonia is increasingly recognized as a viable alternative fuel that could significantly reduce greenhouse gas emissions without requiring major modifications to existing engine technologies. However, its high auto-ignition temperature, slow flame speed, and narrow flammability range present significant barriers, particularly under high-speed combustion conditions. This review explores the potential of ammonia as a sustainable fuel for internal combustion engines, focusing on its advantages and challenge. The review draws on a wide range of studies, from NH3 production, application, to the combustion mechanisms, that explore various strategies for enhancing NH₃ combustion in both spark ignition and compression ignition engines. Fundamentals and key approaches discussed include using hydrogen and hydrocarbon fuels as combustion promoters, which have been shown to improve ignition and flame propagation. Literature on fuel injection strategies, such as port fuel injection, direct injection, and dual-fuel injection, are examined to highlight their influence on NH₃-air mixing and combustion efficiency. Furthermore, the review delves into advanced ignition technologies, such as low-temperature plasma ignition, turbulent jet ignition, and laser ignition, which are explored for the potential to overcome the ignition difficulties associated with NH₃. After a comprehensive analysis based on the literature, the intelligent liquid-gas twin-fluid co-injection system (iTFI) emerges as a promising approach, offering improved combustion stability and efficiency through better fuel-air mixture preparation. By synthesizing the existing research, this review outlines the progress made in NH₃ combustion and identifies areas where further study is needed to fully realize its potential as a sustainable fuel. Peer reviewed

Publisher Copyright: © 2024 The Authors Ammonia is increasingly recognized as a viable alternative fuel that could significantly reduce greenhouse gas emissions without requiring major modifications to existing engine technologies. However, its high auto-ignition temperature, slow flame speed, and narrow flammability range present significant barriers, particularly under high-speed combustion conditions. This review explores the potential of ammonia as a sustainable fuel for internal combustion engines, focusing on its advantages and challenge. The review draws on a wide range of studies, from NH3 production, application, to the combustion mechanisms, that explore various strategies for enhancing NH₃ combustion in both spark ignition and compression ignition engines. Fundamentals and key approaches discussed include using hydrogen and hydrocarbon fuels as combustion promoters, which have been shown to improve ignition and flame propagation. Literature on fuel injection strategies, such as port fuel injection, direct injection, and dual-fuel injection, are examined to highlight their influence on NH₃-air mixing and combustion efficiency. Furthermore, the review delves into advanced ignition technologies, such as low-temperature plasma ignition, turbulent jet ignition, and laser ignition, which are explored for the potential to overcome the ignition difficulties associated with NH₃. After a comprehensive analysis based on the literature, the intelligent liquid-gas twin-fluid co-injection system (iTFI) emerges as a promising approach, offering improved combustion stability and efficiency through better fuel-air mixture preparation. By synthesizing the existing research, this review outlines the progress made in NH₃ combustion and identifies areas where further study is needed to fully realize its potential as a sustainable fuel. Peer reviewed