ScholarWorks@KOREA RESEARCH INSTITUTE OF SHIPS & OCEAN ENGINEERINGThe ScholarWorks digital repository system captures, stores, indexes, preserves, and distributes digital research material.https://www.kriso.re.kr:443/sciwatch2024-03-13T06:10:24Z2024-03-13T06:10:24ZInvestigating Electrode-Ionomer Interface Phenomena for Electrochemical Energy ApplicationsSo Yeong JoHanjoo KimHyein ParkAhn, Chi YeongDong Young Chunghttps://www.kriso.re.kr/sciwatch/handle/2021.sw.kriso/103182024-02-20T07:00:06Z2024-02-01T00:00:00ZTitle: Investigating Electrode-Ionomer Interface Phenomena for Electrochemical Energy Applications
Authors: So Yeong Jo; Hanjoo Kim; Hyein Park; Ahn, Chi Yeong; Dong Young Chung
Abstract: The endeavor to develop high-performance electrochemical energy applications has underscored the growing importance of comprehending the intricate dynamics within an electrode's structure and their influence on overall performance. This review investigates the complexities of electrode-ionomer interactions, which play a critical role in optimizing electrochemical reactions. Our examination encompasses both microscopic and meso/macro scale functions of ionomers at the electrode-ionomer interface, providing a thorough analysis of how these interactions can either enhance or impede surface reactions. Furthermore, this review explores the broader-scale implications of ionomer distribution within porous electrodes, taking into account factors like ionomer types, electrode ink formulation, and carbon support interactions. We also present and evaluate state-of-the-art techniques for investigating ionomer distribution, including electrochemical methods, imaging, modeling, and analytical techniques. Finally, the performance implications of these phenomena are discussed in the context of energy conversion devices. Through this comprehensive exploration of intricate interactions, this review contributes to the ongoing advancements in the field of energy research, ultimately facilitating the design and development of more efficient and sustainable energy devices.2024-02-01T00:00:00ZTe hexagonal nanotubes with fast 1-dimensional Zn ion diffusion for high-performance zinc-ion battery cathodesMihyun KimHyosik KimSi-Hwan LeeSeungho YuWon KimJong-Seong BaeAhn, Chi YeongShim, Hyung wonJi Eun LeeSeung-Ho Yuhttps://www.kriso.re.kr/sciwatch/handle/2021.sw.kriso/103312024-01-11T01:00:11Z2024-02-01T00:00:00ZTitle: Te hexagonal nanotubes with fast 1-dimensional Zn ion diffusion for high-performance zinc-ion battery cathodes
Authors: Mihyun Kim; Hyosik Kim; Si-Hwan Lee; Seungho Yu; Won Kim; Jong-Seong Bae; Ahn, Chi Yeong; Shim, Hyung won; Ji Eun Lee; Seung-Ho Yu
Abstract: The need for advanced next-generation secondary batteries have been urgently demanded for improved, sustainable, and eco-friendly energy storage systems. Aqueous rechargeable zinc ion batteries (ARZIBs) have garnered substantial attention as a substitute for lithium-ion batteries owing to their exceptional stability, environmentally friendly features, and cost-effectiveness. In this study, it is found that tellurium hexagonal nanotubes with a unique crystal growth orientation of [001] are of promising cathode materials for enhancing the performance of zinc ion batteries owing to their outstanding reaction kinetic properties. Additionally, the hollow interior of the nanotubes effectively mitigates the volume changes of tellurium during the charging and discharging processes. These research findings are expected to solidify the potential of tellurium hexagonal nanotubes as reliable cathode materials, significantly contributing to the commercialization of zinc ion battery technology in the future.2024-02-01T00:00:00ZPerformance and mass transfer evaluation of PEM fuel cells with straight and wavy parallel flow channels of various wavelengths using CFD simulationKaiser, RashedAhn, Chi-YeongKim, Yun-HoPark, Jong-Chunhttps://www.kriso.re.kr/sciwatch/handle/2021.sw.kriso/103462024-01-11T08:00:04Z2024-01-01T00:00:00ZTitle: Performance and mass transfer evaluation of PEM fuel cells with straight and wavy parallel flow channels of various wavelengths using CFD simulation
Authors: Kaiser, Rashed; Ahn, Chi-Yeong; Kim, Yun-Ho; Park, Jong-Chun
Abstract: Polymer electrolyte membrane fuel cells (PEMFC) have the potential to replace conventional fossil fuels. The flow channel is a key part of the PEMFC that facilitates reactant mass transfer into the gas diffusion layer, catalyst layer, and membrane. Overall performance of the PEMFC mostly depends on the efficient mass transfer, pressure drop, and water management within this channel. In the straight channel mass transfer occurs by diffusion while in the wavy channel mass transfer occurs through convection. In this study, the performance and mass transfer evaluation of a PEMFC with a straight flow channel and wavy flow channels of different wavelengths (λ = 4, 4.8, and 6) were compared using a commercial solver (STAR-CCM+16.04). The simulation results were validated experimentally and the results were in good agreement. Comparison of the simulation results established that the mass transfer through diffusion and convection was more enhanced in the case of wavy channels. ? 2023 Hydrogen Energy Publications LLC2024-01-01T00:00:00ZOptimization of hydrophobic additives content in microporous layer for air breathing PEMFCHyukjae ChoiHee Ji ChoiSun Young KangJunho KimHosung ChoiAhn, Chi YeongKang, Hee JinIlchai LaOk-Hee KimYong-Hun ChoYung-Eun Sunghttps://www.kriso.re.kr/sciwatch/handle/2021.sw.kriso/103282024-01-17T09:00:04Z2024-01-01T00:00:00ZTitle: Optimization of hydrophobic additives content in microporous layer for air breathing PEMFC
Authors: Hyukjae Choi; Hee Ji Choi; Sun Young Kang; Junho Kim; Hosung Choi; Ahn, Chi Yeong; Kang, Hee Jin; Ilchai La; Ok-Hee Kim; Yong-Hun Cho; Yung-Eun Sung
Abstract: This study explored the ideal polytetrafluoroethylene (PTFE) content in the microporous layer (MPL) for proton exchange membrane fuel cells (PEMFCs) operating under specific conditions: room temperature, ambient pressure, and no-external humidification. The physical properties of MPL were evaluated through FE-SEM and contact angle measurements, and to understand how these properties affect the performance of MPL under unique operating conditions only dependent on internally generated water, the maximum power density at various PTFE contents was compared and electrochemically investigated. Both 5% and 20% PTFE contents exhibited superior performance, and the optimal PTFE content for passive-type cells was determined through performance and durability evaluations. These findings are expected to enhance fuel cell technology’s suitability as a compact, portable power source and offer valuable operational insights.2024-01-01T00:00:00Z