SBIR Phase I: Improved, Lightweight, Bipolar Plates for Fuel Cell Using Nanotube-Filled Polybutylene Terephthalate Composite

提出了一种新型导电复合材料，用于燃料电池串联相邻电池间的双极极板。这种新型复合材料重量轻，有望减少制造时间和将复杂的场流通道整合到板表面的成本。导电材料由嵌有碳纳米管的聚对苯二甲酸丁二酯热塑性塑料组成，其尺寸为10 × 100埃。该材料将被加工成粉末，用于压缩成型、挤压和注射成型试验。复合材料的加工和制造方法将被优化，以生产用于测试的薄板。研究了增塑剂和偶联剂对材料加工的影响。成型复合材料的物理和机械性能将被确定，包括透气性、拉伸和弯曲强度、热膨胀系数、电阻率和对其他电池组件的接触电阻。这些板将在质子交换膜燃料电池（PEMFC）中进行测试，并与含有石墨和其他复合材料板的电池进行电化学性能比较。在80℃下使用的影响将通过在连续电池运行后重新建立物理和机械特性来评估。

A new conductive composite material is proposed for use in fuel cells as a bipolar plate between adjoining cells in series. The new composite material is lightweight and promises to reduce manufacturing time and costs associated with incorporating complex field flow channels into the plate surface. The conductive material consists of polybutylene terephthalate thermoplastic embedded with carbon nanotubes, which are 10x100 Angstroms in size. The material will be processed to reduce pellets to a powder for compression molding, extrusion and injection molding trials. Processing and manufacturing methods for the composite will be optimized to produce thin plates for testing. The effects of incorporating plasticizers and coupling agents on the material processing will be investigated. Physical and mechanical properties of the molded composite will be determined including gas permeability, tensile and flexural strength, thermal expansion coefficient, resistivity and contact resistance against other cell components. The plates will be tested in a proton exchange membrane fuel cell (PEMFC) and the electrochemical performance compared with cells containing plates made of graphite and other composites. The effects of service use at 80oC will be assessed by re-establishing the physical and mechanical characteristics after continuous cell operation.