Automated Fuel Cell Stack Assembly: Lessons in Design-for-Manufacture

Abstract

Within the next decade, proton-exchange membrane (PEM) fuel cell technology will need to progress from low-volume to high-volume production. The second of two fully-functional fuel cell stack assembly robotic stations is being developed to meet the requirements for this transition; meanwhile, a fuel cell stack is being modified to ease the challenges of automated assembly. This document outlines the most recent iteration of the robotic fuel cell assembly station, challenges encountered, stack design features which impair automation efforts, stack modifications and their impact on assembly success, and a methodology for designing successful stacks in tomorrow’s automated assembly plants. Numerous design aspects of the stack, intended for manual assembly, proved challenging for robotic assembly: in particular, those pertaining to component tolerances, stack compliance, fasteners, environmental requirements, overall stack alignment, MEA handling, and part alignment verification. Each of these challenges was addressed during the refinement of the second robotic station, in many cases via modification of the stack. Nonetheless, each of these factors represents a continuing liability, both in cost and time, to rapid, accurate, reliable stack assembly. Methodology for incorporating these critical design-for-manufacture considerations into future stack designs is therefore addressed as well. As the stack assembly workcell continues to improve, research will focus upon further stack redesign specifically to optimize fuel cell manufacturing throughput.