Integrated Planar Solid Oxide Fuel Cell: Steady-State Model of a Bundle and Validation through Single Tube Experimental Data

The models of solid oxide fuel cells (SOFCs), which are available in the open literature,may be categorized into two non-overlapping groups: microscale or macroscale. Recent progressin computational power makes it possible to formulate a model which combines both approaches,the so-called multiscale model. The novelty of this modeling approach lies in the combination ofthe microscale description of the transport phenomena and electrochemical reactions’ with thecomputational fluid dynamics model of the heat and mass transfer in an SOFC. In this work,the mathematical model of a solid oxide fuel cell which takes into account the averaged microstructureparameters of electrodes is developed and tested. To gain experimental data, which are used toconfirm the proposed model, the electrochemical tests and the direct observation of the microstructurewith the use of the focused ion beam combined with the scanning electron microscope technique(FIB-SEM) were conducted. The numerical results are compared with the experimental data fromthe short stack examination and a fair agreement is found, which shows that the proposed modelcan predict the cell behavior accurately. The mechanism of the power generation inside the SOFC isdiscussed and it is found that the current is produced primarily near the electrolyte–electrode interface.Simulations with an artificially changed microstructure does not lead to the correct prediction of thecell characteristics, which indicates that the microstructure is a crucial factor in the solid oxide fuelcell modeling.

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Model predictive control of the solid oxide fuel cell stack temperature with models based on experimental data

Journal of Power Sources ◽

10.1016/j.jpowsour.2014.11.126 ◽

2015 ◽

Vol 277 ◽

pp. 239-250 ◽

Cited By ~ 26

Author(s):

Antti Pohjoranta ◽

Matias Halinen ◽

Jari Pennanen ◽

Jari Kiviaho

Keyword(s):

Experimental Data ◽

Fuel Cell ◽

Model Predictive Control ◽

Solid Oxide Fuel Cell ◽

Predictive Control ◽

Solid Oxide ◽

Oxide Fuel ◽

Fuel Cell Stack

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Modelling the leakage current in a solid oxide fuel cell with bi-layer electrolyte

Journal of Electrochemical Science and Engineering ◽

10.5599/jese.770 ◽

2020 ◽

Author(s):

Balaji Krishnamurthy ◽

Hariharan Ramasubramanian

Keyword(s):

Experimental Data ◽

Fuel Cell ◽

Solid Oxide Fuel Cell ◽

Leakage Current ◽

Operating Temperature ◽

Cell Voltage ◽

Solid Oxide ◽

Oxide Fuel ◽

Operating Cell ◽

Interfacial Oxygen

<p class="PaperAbstract">A mathematical model is developed to study the leakage current in a solid oxide fuel cell (SOFC) with a bi-layer electrolyte. The model predicts the variation of leakage current and power density with various design and operating factors of SOFC, namely thickness of the bi-layer electrolyte, operating temperature and operating cell voltage. The interfacial oxygen pressure in SOFC is also studied as a function of the thickness of YSZ layer. Modelling results are compared with experimental data and found to compare well.</p>

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Reliability analysis for a multi-stack solid oxide fuel cell system subject to operation condition-dependent degradation

Journal of Quality in Maintenance Engineering ◽

10.1108/jqme-04-2020-0021 ◽

2020 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Konrad W. Eichhorn Colombo ◽

Peter Schütz ◽

Vladislav V. Kharton

Keyword(s):

Experimental Data ◽

Fuel Cell ◽

Solid Oxide Fuel Cell ◽

Reliability Analysis ◽

Dynamic Program ◽

Solid Oxide ◽

System Level ◽

Oxide Fuel ◽

Content Type ◽

Start Up

PurposeA reliability analysis of a solid oxide fuel cell (SOFC) system is presented for applications with strict constant power supply requirements, such as data centers. The purpose is to demonstrate the effect when moving from a module-level to a system-level in terms of reliability, also considering effects during start-up and degradation.Design/methodology/approachIn-house experimental data on a system-level are used to capture the behavior during start-up and normal operation, including drifts of the operation point due to degradation. The system is assumed to allow replacement of stacks during operation, but a minimum number of stacks in operation is needed to avoid complete shutdown. Experimental data are used in conjunction with a physics-based performance model to construct the failure probability function. A dynamic program then solves the optimization problem in terms of time and replacement requirements to minimize the total negative deviation from a given target reliability.FindingsResults show that multi-stack SOFC systems face challenges which are only revealed on a system- and not on a module-level. The main finding is that the reliability of multi-stack SOFC systems is not sufficient to serve as sole power source for critical applications such as data center.Practical implicationsThe principal methodology may be applicable to other modular systems which include multiple critical components (of the same kind). These systems comprise other electrochemical systems such as further fuel cell types.Originality/valueThe novelty of this work is the combination of mathematical modeling to solve a real-world problem, rather than assuming idealized input which lead to more benign system conditions. Furthermore, the necessity to use a mathematical model, which captures sufficient physics of the SOFC system as well as stochasticity elements of its environment, is of critical importance. Some simplifications are, however, necessary because the use of a detailed model directly in the dynamic program would have led to a combinatorial explosion of the numerical solution space.

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