Lightweight High-Performance Fuel Cells for Unmanned Aerial Vehicle Propulsion

质子交换膜燃料电池（PEMFC）将氢的化学能直接转化为电能，并产生水和热。PEMFC动力装置是汽车和分布式电源应用中最有前途的电源。目前PEMFC被认为是无人机（UAV）的替代电源。但是，与其他电源（例如，尽管已经用于为UAV提供动力的燃料电池（例如，内燃机、电池和涡轮螺旋桨发动机）的功率密度低得多，但是PEMFC动力装置的功率密度要低得多。因此，低功率密度（重型燃料电池动力装置的低功率输出）是燃料电池动力无人机（FCUAV）面临的最关键挑战。* 传统的石墨双极板占燃料电池堆重量的近80%。膜水合是低温（~70 ° C）PEMFC最关键的挑战之一，因为它直接影响燃料电池的性能和效率。为了使膜适当地水合，使用常规技术，通常需要单独的加湿器和相关系统，这使得常规燃料电池动力装置笨重且庞大。* 首席研究员小组在PEMFC和PEMFC电池动力系统领域做出了重大贡献：*（1）开发、实现并应用了PEMFC的全面三维通用模型，以处理两相流动和传输机制。* (2)成功地建立了一个燃料电池试验台，并进行了改进，用于研究燃料电池性能和验证PEMFC的通用模型。* (3)已经设计并建立了静电纺丝装置，以制造具有更好耐用性和更高性能的纳米纤维和催化剂涂覆的气体扩散层。(4)针对车用和便携式燃料电池-蓄电池混合动力系统的电源管理策略已经被开发出来并得到了实验验证。* （5）FCUAV原型，重点是燃料电池动力装置的控制策略。*为了构建具有高效率和长续航力的FCUAV，迫切需要开发一种有效的系统方法，用于构建具有创新设计和有效且负担得起的制造方法的轻质PEMFC堆。在该提案中，将提出膜、电极和双极板的创新设计和制造，并通过数值和实验方法进行表征和研究;并将建立一种有效的系统方法来构建具有高性能的轻质PEMFC堆。该研究成果将显著提高PEMFC的性能，降低成本。沿着高素质人才的培养和专业技术的发展，将对FCUAV的国防和民用应用产生积极和实质性的影响。

A Proton Exchange Membrane Fuel Cell (PEMFC) converts the chemical energy of hydrogen directly into electrical energy with the generation of water and heat. The PEMFC powerplant is the most promising power source for automotive and distributed power applications. Currently PEMFCs are regarded as the alternative power source for Unmanned Aerial Vehicles (UAVs). However, compared with other power sources (e.g., internal combustion engine, battery, and turboprop) that have been used to power UAVs, the power density of the PEMFC powerplant is much lower. Thus, the low power density (low power output by a heavy fuel cell powerplant) is the most critical challenge for fuel cell-powered UAVs (FCUAVs). *** Conventional graphite bipolar plates contribute almost 80% of a fuel cell stack weight. Membrane hydration is one of the most critical challenges for low-temperature (~70 °C) PEMFCs as it directly affects the fuel cell performance and efficiency. In order to properly hydrate the membrane, with the conventional technologies, a separate humidifier and related systems are usually required, which makes the conventional fuel cell powerplants heavy and bulky. *** The Principal Investigator's group has made significant contributions in the fields of PEMFCs and PEMFC-Battery Power Systems:*** (1) A comprehensive three-dimensional General Model of PEMFCs was developed, implemented, and applied to deal with two-phase flow and transport mechanisms.*** (2) A Fuel Cell Test Stand was successfully built, improved, and employed to investigate fuel cell performance and validate the General Model of PEMFCs.*** (3) An electrospinning setup has been designed and built to fabricate nanofibers and catalyst-coated gas diffusion layers with better durability and higher performance.*** (4) Power management strategies for fuel cell-battery hybrid systems with vehicles and portable applications have been developed and the experimentally validated. *** (5) FCUAV prototyping with a focus on the control strategies for the fuel cell powerplant.*** In order to build a FCUAV with high efficiency and long endurance, there is an urgent need to develop an effective systematic methodology for building a lightweight PEMFC stack with innovative designs and by effective and affordable fabrication methods.*** In this proposal, innovative designs and fabrications of membrane, electrode, and bipolar plates will be proposed, characterized, and investigated by numerical and experimental methods; and an effective systematic methodology for building a lightweight PEMFC stack with high performance will be established.*** The results of the proposed research will significantly improve the performance and reduce the cost of PEMFCs. Along with the highly qualified personnel trained and the expertise developed, it will have positive and substantial effects on FCUAVs for defence and civilian applications.