The membrane electrode assembly (MEA) in the proton exchange membrane (PEM) fuel cell needs to be encapsulated by a frame to improve its assembly strength and sealing performance. However, irreversible degradation usually occurs to invalidate the frame and cause the fuel cell fail. In this study, a series of experiments are conducted to simulate operating environment in the fuel cell, and degradation mechanism of the frame is explored. Changes of tensile strength, peeling strength, shearing strength, and bending strength are adopted to evaluate the frame stability, and effects of temperature, water, and acid on these indexes are quantified. It is found that the peeling strength has the most significant decline, which is the primary failure form of the frame. Acid solution provides the main contribution to this failure. In acid solution, hydrogen ions and water molecules permeate the frame, resulting in rapid degradation and separation of the bonding interface. This study reveals the degradation process of the frame for the first time, and helps enhance our understanding of the frame failure.

质子交换膜（PEM）燃料电池中的膜电极组件（MEA）需要用框架封装，以提高其组装强度和密封性能。然而，通常会发生不可逆的退化，使框架失效并导致燃料电池失效。本研究通过一系列实验来模拟燃料电池的运行环境，并探讨框架的退化机制。采用拉伸强度、剥离强度、剪切强度和弯曲强度的变化来评价框架稳定性，并量化温度、水和酸对这些指标的影响。发现剥离强度下降最显着，是框架的主要失效形式。酸溶液是造成这种失败的主要原因。在酸性溶液中，氢离子和水分子渗透框架，导致键合界面快速降解和分离。本研究首次揭示了车架的退化过程，有助于加深我们对车架失效的认识。