Influence of Operating Conditions on the Reliable Performance of Stacks and Integrated Stack Modules

Bjoern, E.; Heller, Thomas; Schimanke, Danilo; Lawrence, Jeremy; Wunderlich, Christian

doi:10.1149/1.3205524

Cited by 9 publications

(6 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In contrary, at three‐quarter length of layer 5 (T 5,3/4 ) the highest temperature and probably the hotspot within these experimental conditions was observed. The location of this hotspot is in good agreement with a thermal 3D simulation of the stack in exothermic fuel cell mode .…”

Section: Resultsmentioning

confidence: 92%

“…Along the cell length, gas channels within the fuel electrode and air electrode compartment distribute the media in co-flow condition. More details about the stack configuration with modeling and experimental results of the temperature distribution along and across the stack and its repeating units can be found elsewhere [24][25][26]. During the experiments the oxygen electrodes of each stack were flushed with 1 slpm per cell air to prevent the accumulation of pure oxygen with its corrosive characteristic in the outlet pipes of the testing facility.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Investigation of the Long‐term Stability of Solid Oxide Electrolysis Stacks under Pressurized Conditions in Exothermic Steam and Co‐electrolysis Mode

2020

View full text Add to dashboard Cite

In this study three identically constructed ten-layer stacks with electrolyte supported cells were tested in exothermic steam and co-electrolysis mode at elevated pressures of 1.4 and 8 bar. Investigations during constant-current operation at a current density of-0.5 A cm-2 and a reactant conversion of 70% over 1,000-2,000 h were carried out. The inlet gas composition for steam electrolysis was 90/10 (H 2 O/H 2) and 63.7/31.3/3.3/1.7 (H 2 O/CO 2 /H 2 /CO) for co-electrolysis operation. All stacks showed highly similar resistances at the beginning of the tests indicating a high level of accuracy and repeatability during manufacturing. The stack operated in steam electrolysis mode at 1.4 bar showed comparably low degradation of 8 mV kh-1 cell-1 , whereas the stack operated at 8 bar showed an approximately four times higher degradation. The third stack was operated in co-electrolysis mode at 1.4 and 8 bar and showed noticeably higher degradation rates than during steam electrolysis mode. The predominant increase of the ohmic resistance during operation was identified to be mainly responsible for the observed degradation of all three stacks, whereas the increase of the polarization resistances played a subordinate role. Within the post-test analysis, noticeably high nickel depletion was observed for the stack operated at the highest pressure in steam electrolysis mode. Furthermore, partial delamination of electrodes was observed. The degradation is discussed with relation to phenomena and experimental parameters during operation.

show abstract

Section: Resultsmentioning

confidence: 92%

Section: Methodsmentioning

confidence: 99%

Investigation of the Long‐term Stability of Solid Oxide Electrolysis Stacks under Pressurized Conditions in Exothermic Steam and Co‐electrolysis Mode

2020

View full text Add to dashboard Cite

show abstract

“…The rapid start-ups and frequent system cycles which could harm the lifetime of the fuel cells are the major challenges for the described applications. Although the general feasibility of planar SOFC stacks to sustain thermal cycles has been demonstrated earlier (8) for stationary applications, rapid cycling with quick start-up times is still a challenge. Cycle tests for the eneramic ® system were performed on single stacks in furnace environment with heating rates of 20 K/min and on insulated core modules in an automated hotbox test bench.…”

Section: Cycle Tests Of Stacks and Core Modulesmentioning

confidence: 99%

Eneramic Power Generator – A Reliable and Cycleable 100W SOFC-System

et al. 2013

View full text Add to dashboard Cite

Off-grid power generation is considered as an attractive market for fuel cells. For this purpose, a compact SOFC battery hybrid system was developed that operates on commercially available fuels. Due to its progressive thermal packaging, the mobile prototype achieves a net efficiency of 22 % with commercial BoP components. It was possible to reduce the cold start time of the system by direct cathode preheating with burner off-gas. Thus, the system is designed for frequent start-up and cycling capability. In consequence the planar SOFC stack was tested with rapid heating rates up to 20 K/min in furnace and hotbox environment. The degradation caused by system cycling is less than 0.1 % per cycle. Finally, the optimization of stack temperature conditions has improved the lifetime of the SOFC stack significantly.

show abstract

“…The bipolar plates with lateral dimensions of 130x150 mm² are currently the largest interconnects manufactured via powder metallurgy. As reported, the advantages of the CFY stack are the high power density, homogeneous temperature distribution and a wide window of operation temperature (750-850°C) (4). Additionally, variety of SOFC systems needs a stack which is capable to sustain thermal and reduction/oxidation (RedOx) cycling with minimal degradation.…”

Section: Introductionmentioning

confidence: 99%

“…Additionally, variety of SOFC systems needs a stack which is capable to sustain thermal and reduction/oxidation (RedOx) cycling with minimal degradation. It was shown previously (4,5,6) that stack testing for large units (30-cell stacks) can be easily performed under thermally self-sustaining operation conditions in heat isolated compartment (i.e. in a hotbox).…”

Section: Introductionmentioning

confidence: 99%

CFY-Stacks for Use in Stationary SOFC and SOEC Applications

et al. 2013

View full text Add to dashboard Cite

Fraunhofer IKTS and Plansee SE continuously develop SOFC stacks with Chromium based interconnects (CFY) and electrolyte supported cells based on Scandia doped Zirconia. This technology has a great potential for cost-effective manufacturing and rapid up-scaling due to availability of major stack components and essential improvements in manufacturing made last year. The stacks are already available on the market and are in test at several potential customers. The paper gives an overview of the current status of CFY-stack development focused on performance map and system cycling. The results of operation of CFY-stacks in modules with stacks working on different fuels with and without internal steam reforming in partial and full load are presented.

show abstract

Influence of Operating Conditions on the Reliable Performance of Stacks and Integrated Stack Modules

Cited by 9 publications

References 0 publications

Investigation of the Long‐term Stability of Solid Oxide Electrolysis Stacks under Pressurized Conditions in Exothermic Steam and Co‐electrolysis Mode

Investigation of the Long‐term Stability of Solid Oxide Electrolysis Stacks under Pressurized Conditions in Exothermic Steam and Co‐electrolysis Mode

Eneramic Power Generator – A Reliable and Cycleable 100W SOFC-System

CFY-Stacks for Use in Stationary SOFC and SOEC Applications

Contact Info

Product

Resources

About