Abstract: Environment-friendly air-breathing proton exchange membrane fuel cells （PEMFCs） have been prospected as the next generation of portable power sources with a brilliant commercial prospect due to their relatively small volume with simplification of air supply and humidifying system，high energy conversion efficiency，high power density，clean and pollution-free. The related research is becoming one of the hottest topics in fuel cell. In this paper，the research progress of air-breathing proton exchange membrane fuel cell is reviewed with respect to structure，mechanism，components，and performance. Perfecting the porosity and hydrophobicity of cathode catalyst layer of air electrode （cathode） would accelerate oxygen transfer and water removal，and improve air activation ability. The composition，structure and thickness of gas diffusion layer also influence gas permeability and water undock. Applicable structure design and material selection can regulate temperature and reinforce cross-ventilation，and the application of self-humidifying technology can maintain the stability of fuel cell at low humidity.

Key words: fuel cells, hydrogen, air-breathing, cathode catalyst layer, gas diffusion layer, design, self-humidification

摘要： 空气自呼吸质子交换膜燃料电池具有系统体积小、能量密度高、能量转化效率高和清洁无污染、无需复杂的空气供给及增湿系统等优点，是极具商业前景的新一代中小功率便携式电源，其相关研究为燃料电池领域的热点研究课题。本文综述了近年来此类电池在结构、机理、组成元件、性能等方面的研究进展，认为改善阴极催化层孔隙率和疏水性等能显著加快氧气传输和水移除，提高氧气活化能力；气体扩散层的组成、结构和厚度亦影响其气体透过性和水移除效果；合适的结构设计和材料选取能调节池体温度，强化空气对流；膜电极免增湿技术的应用可以维持电池在低湿度下较高质子传导率和系统稳定性，这是空气自呼吸质子交换膜燃料电池实现商业化的重要研究方向。

关键词: 燃料电池, 氢, 空气自呼吸, 阴极催化层, 气体扩散层, 设计, 免增湿