The cold start problem is one of major obstacles to overcome for the commercialization of fuel cell
vehicles. However, the cold start characteristics of fuel cell systems are very complicated since various
phenomena, i.e. ice-blocking, electro-chemical reactions, heat transfer, and defrosting of BOP components, are
involved in them. This paper presents a framework to approach the problem at a full stack scale using Axiomatic
Design (AD). It was characterized in terms of Functional Requirements (FRs) and Design Parameters (DPs)
while their relations were established in a design matrix. Considering the design matrix, the endplates should
have low thermal conductivity and capacity without increase in weight or decrease in structural stiffness.
Consequently, composite sandwich endplates were proposed and examined both through finite element
analyses and experiments simulating cold start conditions. From the examinations, it was found that the
composite sandwich endplates significantly contributed to improving the cold start characteristics of PEMFC.