Design of a Forming Process for Increasing the Contact Length of Corrugated Plates in Molten Carbonate Fuel Cells

Youngseok Oh ,Seong-Hoon Kang,Jaimyun Jung,In Yong Moon,Se Jong Kim ,Ho Won Lee

doi:10.3390/met11071112

Abstract

In molten carbonate fuel cell (MCFC) systems, it is known that the shape of corrugated plates has a significant influence on performance, durability, and cost. A corrugated plate with a repeating open trapezoidal-shaped slot supports membrane electrode assembly and provides a gas flow channel. To increase the efficiency of the MCFC, the slot between the corrugated and center plates has a relatively large contact length. However, increasing the contact length of the slot increases the risk of necking or fracture generation at the corner of the slot. Therefore, we focus on the development of forming technology of corrugated plate which has large contact length of slots without any necking or fracture. To this end, numerical simulation was conducted to determine the appropriate process and tool design. In the simulation, to capture shear fracture during the forming process of slots, the normalized Cockroft–Latham ductile fracture model was used. The critical value for slitting and fracture was evaluated by comparing the deformed shapes in the slitting plane obtained from experimental and simulation results. Based on simulation results, a reasonable design concept of the two-stage forming process was suggested to increase the contact length of the slot without necking or fracture. In addition, the experiment results confirmed the validity of the proposed forming process and tool design.

Highlights

Molten carbonate fuel cells (MCFCs) are in the spotlight as a new energy source to replace fossil fuels because they are thermally and electrically efficient and environmentally friendly
Unlike low temperature fuel cells, which can use platinum electrodes, MCFCs can use non-precious metals such as nickel as electrode catalysts since they operate at high temperatures of 650 ◦C and above
There is a limitation in finding materials for the corrugated plate of MCFCs which needs both high corrosion resistance and mechanical strength for use at high temperatures [1,2]

Summary

Introduction

Molten carbonate fuel cells (MCFCs) are in the spotlight as a new energy source to replace fossil fuels because they are thermally and electrically efficient and environmentally friendly. Metals 2021, 11, 1112 ing processes was conducted based on a ductile fracture model to increase the contact length of the slot for the corrugated plate. A thickness of 200 μm at the corner of the slot was regarded as fracture or necking in the simulation because of insufficient plate strength and numerical error. The numerically obtained design for the maximum contact length was experimentally verified

One-Stage Forming Process

Findings

Two-Stage Forming Process