The gas diffusion layer (GDL) is one of the most important parts of a proton exchange membrane fuel cell, that plays a key role transporting the current to the collector plates, distributing the reactant gases to the catalyst surface, and evacuating heat and water that is generated during the redox reactions inside the fuel cell. Speaking in terms of production cost, the GDL represents up to 45% of the total cost of the membrane electrode assembling (MEA). However, and despite its crucial role in a fuel cell, until recent years, the GDLs have not been studied with the same intensity as other MEA components, such as the catalyst or the proton exchange membrane. In this work, we present the production process, at laboratory scale, of a low cost GDL, using a non-woven paper-making process. A relevant aspect of this GDL is that up to 40% of their composition is natural cotton, despite which they present good electrical and thermal conductivity, high porosity, good pore morphology, high hydrophobicity as well as gas permeability. Furthermore, when the GDL with its optimum cotton content was tested in a single open cathode fuel cell, a good performance was obtained, which makes this GDL a promising candidate for its use in fuel cells.

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Cation transport through the electrolyte to the anode is one most important steps to understand desolvation and diffusion through the electrolyte phase To help understanding this step, there is a sustained development of sophisticated in situ surface science and electrochemical techniques, and first-principles based computational methods. In this work, we analyze the structure and dynamics of state-of-the-art electrolytes particularly at interfaces of typical intercalation anodes. We use classical reactive molecular dynamics and ab initio molecular dynamics to characterize the interfacial systems, and constrained molecular dynamics to investigate the role of highly structured solvation structures on cation deposition and intercalation.

Lithium metal anode is considered a great candidate because of its high theoretical capacity and negative electrochemical potential. However, key factors like poor cyclability as well as the safety issues related to the uneven lithium electrodeposition, dendrite growth, and unstable solid electrolyte interphase (SEI) are keeping lithium metal batteries away from commercialization. Different attempts both experimentally and theoretically have been done to decode the exact structure and distribution of SEI, but due to the inherent dynamic behavior as well as the lithium reactivity, the exact structure of the SEI and its growth mechanisms are still unclear. In this study with the use of molecular simulation and computational chemistry tools, we investigate the initial nucleation and growth dynamics of different SEI components that provide us with thermodynamics and structural information about the nucleating SEI. Different nucleation and growth mechanisms were studied for the SEI components including LiF, Li2O, and LiOH. An initial mechanism of nucleation is based on the assumption that a Li metal cluster represents a portion of the surface where inhomogeneous Li seeds are nucleating, we use ab initio methods to determine the preferential addition sites for OH or O radicals or fluorine anions. This mechanism allows the study of different structures of SEI in lithium-rich environments simulating initial stages of electrolyte decomposition and SEI formation. Multiple models are studied to understand the formation energies and structures for SEI nanocluster formation in which already formed fragments of SEI are joined together to study the formation of larger SEI clusters. Each of the different components of SEI reveals its preferential growth mechanisms showcasing different degrees of crystallinity and electron density distribution leading to a better understanding of the nucleation and growth of SEI.