Optimum Battery Size for Fuel Cell Hybrid Electric Vehicle With Transient Loading Consideration—Part II

2006 ◽  
Vol 4 (2) ◽  
pp. 176-184 ◽  
Author(s):  
Olle Sundström ◽  
Anna Stefanopoulou
Keyword(s):  
Dynamic Programming ◽  
Fuel Cell ◽  
Hybrid Electric Vehicle ◽  
Polymer Electrolyte Membrane ◽  
Fuel Cell Vehicle ◽  
Energy Losses ◽  
Power Sources ◽  
Electrolyte Membrane ◽  
Optimal Coordination ◽  
Energy Buffer

This study presents a simplified model of a midsized vehicle powered by a polymer electrolyte membrane fuel cell stack together with a lead-acid battery as an energy buffer. The model is used with dynamic programming in order to find the optimal coordination of the two power sources while penalizing transient excursions in oxygen concentration in the fuel cell and the state of charge in the battery. The effects of the battery size on the overall energy losses for different drive cycles are determined, and the optimal power split policies are analyzed to quantify all the energy losses and their paths in an effort to clarify the hybridization needs for a fuel cell vehicle with constraints on dynamically varying variables. Finally, a causal nonpredictive controller is presented. The battery sizing results from the dynamic programming optimizations and the causal controller are compared.

Optimum Battery Size for Fuel Cell Hybrid Electric Vehicle— Part I

2006 ◽  
Vol 4 (2) ◽  
pp. 167-175 ◽  
Author(s):  
Olle Sundström ◽  
Anna Stefanopoulou
Keyword(s):  
Fuel Cell ◽  
Fuel Consumption ◽  
Hybrid Electric Vehicle ◽  
Polymer Electrolyte Membrane ◽  
Cell System ◽  
Fuel Cell Vehicle ◽  
Regenerative Braking ◽  
Energy Losses ◽  
Fuel Cell System ◽  
Electrolyte Membrane

This study explores different hybridization levels of a midsized vehicle powered by a polymer electrolyte membrane fuel cell stack. The energy buffer considered is a lead-acid-type battery. The effects of the battery size on the overall energy losses for different drive cycles are determined when dynamic programming determines the optimal current drawn from the fuel cell system. The different hybridization levels are explored for two cases: (i) when the battery is only used to decouple the fuel cell system from the voltage and current demands from the traction motor to allow the fuel cell system to operate as close to optimally as possible and (ii) when regenerative braking is included in the vehicle with different efficiencies. The optimal power-split policies are analyzed to quantify all the energy losses and their paths in an effort to clarify the hybridization needs for a fuel cell vehicle. Results show that without any regenerative braking, hybridization will not decrease fuel consumption unless the vehicle is driving in a mild drive cycle (city drive with low speeds). However, when the efficiency of the regenerative braking increases, the fuel consumption (total energy losses) can be significantly lowered by choosing an optimal battery size.

A New Complex Design for Air-Breathing Polymer Electrolyte Membrane Fuel Cells Aided by Rapid Prototyping

2010 ◽  
Vol 8 (1) ◽  
Author(s):  
Chen-Yu Chen ◽  
Yun-Che Wen ◽  
Wei-Hsiang Lai ◽  
Ming-Chang Chou ◽  
Biing-Jyh Weng ◽  
...  
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Rapid Prototyping ◽  
Polymer Electrolyte ◽  
Polymer Electrolyte Membrane ◽  
Cell Design ◽  
Power Sources ◽  
Air Breathing ◽  
Electrolyte Membrane ◽  
Complex Design

One of the most difficult issues to fabricate a fuel cell with a complex design is the manufacturing method. To solve this difficulty, the authors applied an innovative method of fuel cell fabrication, i.e., rapid prototyping technology. The rapid prototyping technology can both fabricate the complex design and shorten the fabrication time. In this paper, the authors used a 3D software (CATIA) on the fuel cell design and utilized the rapid prototyping to accelerate the prototype development of complex stack designs and to verify the practicability of the new fabrication for fuel cells. The honeycomb shape methanol reservoir and cathode structure design of a direct methanol fuel cell (DMFC) and the complex flow distributor design of a monopolar air-breathing proton exchange membrane fuel cell (PEMFC) stack, which were almost impossibly manufactured by traditional manufacturing, were made in this study. The performance of the traditional air-pumping DMFC and that of an air-breathing DMFC were compared in this study. The feasibility of a complex pseudobipolar design DMFC stack was also verified. For the miniature air-breathing PEMFC made by rapid prototyping with ABS material, its performance is close to the state-of-the-art compared to previous published literatures (Hsieh et al. 2006, “Study of Operational Parameters on the Performance of Micro PEMFCs With Different Flow Fields,” Energy Convers. Manage., 47, pp. 1868–1878; Schmitz, A., Wagner, S., Hahn, R., Uzun, H., and Hebling, C., 2004, “Stability of Planar PEMFC in Printed Circuit Board Technology,” J. Power Sources, 127, pp. 197–205; Hottinen, T., Mikkola, M., and Lund, P., 2004, “Evaluation of Planar Free-Breathing Polymer Electrolyte Membrane Fuel Cell Design,” J. Power Sources, 129, pp. 68–72). A new solution to manufacture complex fuel cell design, rapid prototyping, has been first applied to the fabrication of complicated flow channels in ABS materials and directly used in both DMFC and PEMFC in this paper. Its feasibility was verified and its promising performance was also proved.

Water Management in PEMFC Stack of Fuel Cell Vehicle

2009 ◽  
Author(s):  
Sungho Lee ◽  
Heeseok Jeong ◽  
Inchul Whang ◽  
Taewon Lim
Keyword(s):  
Water Management ◽  
Fuel Cell ◽  
Polymer Electrolyte Membrane ◽  
Gas Diffusion ◽  
Fuel Cell Vehicle ◽  
Performance Loss ◽  
Electrolyte Membrane ◽  
Catalyst Layers ◽  
Diffusion Layers ◽  
Water Behavior

The PEMFC (Polymer Electrolyte Membrane Fuel Cell) requires well hydration for acceptable protonic conductivity, but liquid water in the catalyst layers and gas diffusion layers can cause performance loss due to blockage of reactants to the catalysts. Many activities have been done on the water management in PEMFC stack to guaranty better performance and its longevity. Some approaches for PEMFC stack in Hyundai-motor will be shown in this presentation based on analytic modeling, CFD, and experiment, then some challenges for better understanding of water behavior in PEMFC will be shown at the end of this paper.

scholarly journals CELLULOSIC MATERIALS AS POLYMER ELECTROLYTE MEMBRANE IN FUEL CELL APPLICATION

2016 ◽  
Vol 2 (02) ◽  
Author(s):  
Cynthia L. Radiman ◽  
A. Sarinastiti
Keyword(s):  
Fuel Cell ◽  
Bacterial Cellulose ◽  
Polymer Electrolyte ◽  
Polymer Electrolyte Membrane ◽  
Group Analysis ◽  
Exchange Capacity ◽  
Acetobacter Xylinum ◽  
Basic Material ◽  
Power Sources ◽  
Electrolyte Membrane

Polymer Electrolyte Membrane Fuel Cells (PEMFC) and Direct Methanol Fuel Cell (DMFC) are considered as future power sources in overcoming the fossil-based energy crisis. The objective of this work is to explore one of the natural resources of Indonesia and to improve its properties by chemical modification in order to get the required characteristics as electrolyte membrane. In this work coconut water was used as the basic material. It was fermented by Acetobacter xylinum and the resulting bacterial cellulose was then phosphorylated using a microwave-assisted reaction. Those membranes have been immersed for a varied time ranging between 0 and 8 hours (0-8 h) in a mixture of N,N-dimethylformamide (DMF), phosphoric acid and urea prior to irradiation by microwave for 60 s. Those membranes were characterized by several methods, such as functional group analysis by FTIR, proton conductivity, ion exchange capacity, swelling index, morphology analysis by SEM and phosphorus content analysis by SEM-EDS. From the experimental data, it can be concluded that a phosphorylated bacterial cellulose prepared by a 4h–immersion could be used as an alternative electrolyte membrane for fuel cell applications.Keywords: fuel cell, bacterial cellulose, phosphorylated bacterial cellulose  ABSTRAK Sel bahan bakar membran polimer eletrolit (PEMFC) dan sel bahan bakar metanol (DMFC) merupakan sumber energi masa depan yang dapat mengatasi krisis energi minyak bumi. Tujuan penelitian ini adalah untuk menggunakan bahan alam Indonesia yang dimodifikasi secara kimiawi supaya sifat-sifatnya dapat ditingkatkan untuk memenuhi persyaratan sebagai membran elektrolit. Dalam penelitian ini air kelapa telah digunakan sebagai bahan dasar dan selanjutnya difermentasi oleh Acetobacter xylinum. Selulosa bakterial yang dihasilkan difosforilasi dengan bantuan gelombang mikro. Membran tersebut direndam selama waktu yang bervariasi ( 0-8 jam) dalam campuran N,N-dimetilasetamida (DMF), asam fosfat dan urea sebelum diiradiasi dengan gelombang mikro selama 60 detik. Karakterisasi membran dilakukan dengan berbagai metoda, antara lain analisis gugus fungsi dengan FTIR, konduktivitas proton, kapasitas penukar ion, indeks penggembungan, analisis morfologi dengan SEM dan analisis kadar fosfor dengan SEM-EDS. Dari data yang diperoleh disimpulkan bahwa selulosa bakterial yang difosforilasi dengan proses perendaman selama 4 jam dapat digunakan sebagai alternatif untuk membran elektrolit dalam aplikasi sel bahan bakar.Kata kunci: sel bahan bakar, selulosa bakterial, selulosa bakterial terfosforilasi

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