【作者】 张海峰；

【导师】 衣宝廉；

【作者基本信息】 中国科学院研究生院（大连化学物理研究所） ， 化学工程， 2004， 硕士

【摘要】 质子交换膜燃料电池(PEMFC)具有较高的功率密度和能量转化效率,最有可能成为电动车的动力源。双极板是质子交换膜燃料电池的关键部件之一,不但影响电池的性能,而且影响电池的成本,成为燃料电池产业化的瓶颈。目前双极板材料的研究主要集中在金属板(主要是不锈钢)和石墨板/碳板两种材料上,而这两种材料各有优缺点。理想双极板应该结合这些材料的优点:高导电性、耐腐蚀、重量轻、强度高、密封性能好、化学稳定性好、导热好而且还要易于加工。本论文提出了一种新的复合双极板的制备方法:薄不锈钢板作分隔板,冲压成流场的柔性石墨板代替不锈钢网作为流场板,兼具了金属双极板和石墨双极板的优点。重点研究了金属分隔板的表面改性对燃料电池性能的影响,采用了电镀、化学镀、离子溅射等方法对金属分隔板进行了表面处理,并研究了处理后的不锈钢板的耐腐蚀性及其与柔性石墨流场板之间的接触电阻。测试结果发现,接触电阻的大小顺序依次是电镀银<溅射银<化学镀锡<TiN<化学镀铅<不锈钢。同时测量了柔性石墨流场板的透气量、各种成分的含量、体电阻等基础数据。另外还研究了流场尺寸对电池性能的影响。最后简要介绍了课题组利用该复合双极板组装了电池组,通过在实际过程中的应用,进一步证实了该种复合双极板的可靠性。更多还原

【Abstract】 Due to the prospects for attaining high power density and energy conversionefficiency, the proton exchange membrane fuel cell (PEMFC) is one of the mostpromising power sources for future electric vehicles. Bipolar plates of PEMFC areone of the critical components which have a major impact not only on theperformance of the stack but also on the cost and have been choke points ofindustrialization.The majority of PEMFC stack producers utilize bipolar plate based on graphite,carbon composites or metals (principally, stainless steel). Each of these materials hascharacteristics that are beneficial for fuel cell applications, but are limited by others.An idea bipolar plate would incorporate the merits of these materials, such that itwould be high in electrical conductivity and corrosion protection, of low density butwith high mechanical strength, impermeable to reactant gases, chemically inert,thermal conductivity, and allow for ease of manufacture.A novel composite bipolar plate is studied and prepared in this thesis, which isadopted stainless steel plate as its supporting plate and flexible graphite plate as itsflow field plate. The composite bipolar plate combined advantages with graphite andmetal plates, which meets the conditions of an idea bipolar plate.The effect of thin stainless steel plate on performance of PEM fuel cell has beenstudied. Coating systems for metal plates are including electroplate, electrolessplating, ion eject and etc. The contact resistance between the flexible graphite plateand the coated stainless steel plate has been investigated. At the same time, theflexible graphite flow field plate has been discussed, including gas penetrability,component and body resistance. The dimensions of flow field also have an importanteffect on performance of PEM fuel cell. Stack assembled with composite plates has been used for engine, which furtherconfirmsreliability of the composite plate.更多还原