0
RESEARCH PAPERS

# To Achieve the Best Performance Through Optimization of Gas Delivery and Current Collection in Solid Oxide Fuel Cells

[+] Author and Article Information
P. W. Li

Department of Mechanical Engineering,  University of Pittsburgh, Pittsburgh, PA 15261pel1@engr.pitt.edu

S. P. Chen, M. K. Chyu

Department of Mechanical Engineering,  University of Pittsburgh, Pittsburgh, PA 15261

J. Fuel Cell Sci. Technol 3(2), 188-194 (Dec 19, 2005) (7 pages) doi:10.1115/1.2174068 History: Received August 01, 2005; Revised December 19, 2005

## Abstract

Aimed at improving the maximum available power density in a planar-type solid oxide fuel cell, an analytical model is proposed in this work to find the optimum size of a current collector that collects the current from a specific active area of the electrode-electrolyte layer. Distributed three-dimensional current collectors in gas delivery field are designated to allow a larger area of the electrode-electrolyte layer to be active for electrochemical reaction compared to conventional designs that gas channels are separated by current collectors. It has been found that the optimal operating temperature of a planar-type solid oxide fuel cell might be around $850°C$, if the sizes of the distributed current collectors and their control areas are optimized. Decreasing the size of both the current collector and its control area is advantageous in achieving a higher power density. Studies also show that the optimal sizes of the current collector and the current collection area investigated at $850°C$ and zero concentration polarization are applicable to situations of different operating temperatures, and different concentration polarizations. The optimization results of the sizes of current collectors and their control areas are relatively sensitive to the contact resistance between the current collectors and the electrodes of the fuel cell. Results of great significance are provided in the analysis, which will help designers to account for the variation of contact resistance in optimization designing of a bipolar plate of fuel cells.

<>

## Figures

Figure 1

Schematic of the terminal voltage-current curve of a fuel cell

Figure 3

Schematic of gas delivery and current collection through the bipolar plate in a solid oxide fuel cell

Figure 5

A circuit modeling the current collection through a current collector from an area of electrochemical reaction

Figure 6

Power density versus current density at different rc values in a control area of ro=1.5mm and at a temperature of 850°C

Figure 7

Variation of the power density versus the current density and the radius of the current collector in a current collection area of ro=1.5mm; the operating temperature is 850°C

Figure 8

The sizes of the optimum current collectors and their corresponding control areas at an operating temperature of 850°C

Figure 9

The optimal ratio of rc∕ro and the optimized maximum power densities versus the current collection area of radius ro at a temperature of 850°C

Figure 10

The power densities based on the optimized match of rc-ro at ro=1.5mm and temperatures ranging from 700°C to 1000°C

Figure 11

Comparison of the power densities obtained through optimization at a specific temperature with those obtained using the optimum current collector radius of rc=0.86mm from the case of 850°C (all control areas have a radius of ro=1.5mm)

Figure 12

The power densities obtained through optimization in comparison to those obtained based on a current collector size of rc=0.86mm, which is the optimum size of the current collector at zero concentration polarization (temperatures of all cases are 850°C)

Figure 13

Comparison of the power densities at different Rcont. (The rc for the open symbols is based on the current collector size from the optimization at contact resistance of Rcont=0.01Ωcm2; and the rc for the solid symbols is based on the optimization at an indicated contact resistance in the legend. Temperatures of all cases are 850°C.)

Figure 4

Distributed current collectors in gas delivery fields of a solid oxide fuel cell

Figure 2

Schematic of the relationship of voltage and power at varying current densities in a fuel cell

## Discussions

Some tools below are only available to our subscribers or users with an online account.

### Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related Proceedings Articles
Related eBook Content
Topic Collections