Current distribution measurements in a PEFC with net flow geometry

Noponen, Matti; Ihonen, Jari; Lundblad, Anders; Lindbergh, Göran

doi:10.1023/b:jach.0000015616.92074.5d

Cited by 42 publications

(21 citation statements)

References 36 publications

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“…In addition to the conventional serpentine and straight channels [1], a conventional and interdigitated-switchable gas flow field was proposed to improve the cell performance under flooded conditions [2], and a self-draining stirred tank reactor cell was proposed for operations with low relative humidity gases [3]. To develop a detailed understanding of PEFC dynamics, a number of studies on the diagnostics of PEFC, such as on the measurement of the current density distribution and visualization of the water production behavior, have been conducted [3][4][5][6][7][8][9], and an overview was provided on the distributions of current density, high-frequency resistance, gas species and temperature, and including a two-phase visualization [1]. The effects of the distribution of the produced water and the gas composition on the cell performance were discussed using the measured results of the current density distribution [4,5], and the relationships between the local cell impedance and current density have also been investigated [3].…”

Section: Introductionmentioning

confidence: 99%

“…To develop a detailed understanding of PEFC dynamics, a number of studies on the diagnostics of PEFC, such as on the measurement of the current density distribution and visualization of the water production behavior, have been conducted [3][4][5][6][7][8][9], and an overview was provided on the distributions of current density, high-frequency resistance, gas species and temperature, and including a two-phase visualization [1]. The effects of the distribution of the produced water and the gas composition on the cell performance were discussed using the measured results of the current density distribution [4,5], and the relationships between the local cell impedance and current density have also been investigated [3]. The water production behavior in the cathode gas flow channels has been investigated using a transparent fuel cell, and the relation between liquid water behavior and cell performance was demonstrated [6].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Performance characteristics and internal phenomena of polymer electrolyte membrane fuel cell with porous flow field

Tabe

Nasu

Morioka

et al. 2013

Journal of Power Sources

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Polymer electrolyte membrane fuel cells (PEFC) with a porous flow field have been proposed as an alternative to cells with gas flow channels. In this study, the basic characteristics of a PEFC with a porous flow field are identified experimentally. It is shown that stable operation is maintained under conditions at high current density and low stoichiometric ratios of the cathode air, but that operation with low relative humidity gases is difficult in the porous type cell. To clarify the detailed causes of these characteristics, internal phenomena are investigated using a cell specially made for cross-section observations of the cathode porous flow field and temperature distribution measurements on the anode gas diffusion layer (GDL) surface. The direct observations show that the porous type cell is superior in draining the condensed water from the GDL surface, and that hydrophilic properties of the porous material is important for better cell performance at high current densities. The temperature measurements indicate that increases in temperature near the reaction area tends to be larger in the porous type cell than in the channel type cell due to the lower heat removal capability of the porous material, resulting in the unstable operation at relatively low humidities.

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Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Performance characteristics and internal phenomena of polymer electrolyte membrane fuel cell with porous flow field

Tabe

Nasu

Morioka

et al. 2013

Journal of Power Sources

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show abstract

“…[22][23][24][25] This group's approach is similar to that of Stumper et al [18] in that an array of shunt resistors (48 0.1 W) is used to ascertain the current distribution, in this case of a free-breathing cathode PEFC (5 cm 5 cm flow-field). In this technique, some additional control is obtained by the ability to adjust the contact pressure of each of the contact electrodes in turn.…”

Section: Contact Resistancementioning

confidence: 99%

What Happens Inside a Fuel Cell? Developing an Experimental Functional Map of Fuel Cell Performance

et al. 2010

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Fuel cell performance is determined by the complex interplay of mass transport, energy transfer and electrochemical processes. The convolution of these processes leads to spatial heterogeneity in the way that fuel cells perform, particularly due to reactant consumption, water management and the design of fluid-flow plates. It is therefore unlikely that any bulk measurement made on a fuel cell will accurately represent performance at all parts of the cell. The ability to make spatially resolved measurements in a fuel cell provides one of the most useful ways in which to monitor and optimise performance. This Minireview explores a range of in situ techniques being used to study fuel cells and describes the use of novel experimental techniques that the authors have used to develop an 'experimental functional map' of fuel cell performance. These techniques include the mapping of current density, electrochemical impedance, electrolyte conductivity, contact resistance and CO poisoning distribution within working PEFCs, as well as mapping the flow of reactant in gas channels using laser Doppler anemometry (LDA). For the high-temperature solid oxide fuel cell (SOFC), temperature mapping, reference electrode placement and the use of Raman spectroscopy are described along with methods to map the microstructural features of electrodes. The combination of these techniques, applied across a range of fuel cell operating conditions, allows a unique picture of the internal workings of fuel cells to be obtained and have been used to validate both numerical and analytical models.

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“…Liquid water removal from gas channels has also been characterized in detail [15]. The effects of the distribution of the generated water and the gas composition on cell performance were discussed using measured results of the current density distribution [16,17]. For the relationships among the local phenomena, the distribution of purely ohmic cell resistance, the diffusivity in the electrodes and the free gas volume of cells have been measured using the galvanostatic discharge of a fuel cell [18].…”

Section: Introductionmentioning

confidence: 99%