Worldwide, there are growing pressures to develop 'carbonfree' societies, where the majority of the energy is produced from renewable technologies, due to climate change [1], adverse health effects [2], fuel resource depletion [3], security of energy supply, economics [4] and increasing tight international legislations [5]. In response to the above issues, many have proposed hydrogen for use as a replacement energy carrier in future energy economies as it produces no greenhouse gases, GHGs (e.g. CO 2 ) when burned or used in a fuel cell with only electricity, heat and water being formed. A fuel cell is an 'electrochemical' device operating at various temperatures (up to 1,000°C) that continuously and efficiently convert chemical energy (from fuel and oxidant) into electrical energy. There are various types of fuel cell including alkaline (AFC), phosphoric acid (PAFC), molten carbonate (MCFC), solid oxide (SOFC) and polymer electrolyte membrane fuel cell (PEMFC) also known as the proton exchange membrane fuel cell (PEMFC) with an efficiency of up to 60% and operating up to 180°C. There are two types of PEMFC: one uses hydrogen as a fuel and the other, methanol -direct methanol fuel cell (DMFC). They both use membrane electrode assemblies (MEAs) which is the heart of the PEM fuel cell where the electrochemical reactions occur. The MEA is a multilayered membrane consisting of a polymeric membrane sandwiched between catalyst layers and gas diffusion layers (GDLs). Currently, the most promising applications for PEM fuel cell are in the automotive sector with trials of buses, cars and motorcycles becoming increasingly common. Others applications include portable, stationary or backup power units. However, the cost, performance and durability still need to be improved if PEMFC is to become a viable alternative energy technology. For example, as 'a rule of thumb', flow field plates (FFPs) constitute 10% (7.7% for a 5 kWnet stack) of the total cost and more than 60% of the weight in PEM fuel cell stacks. For this reason, the weight, volume and cost of the fuel cell stack can be reduced significantly by improving the layout configuration of FFP and use of lightweight materials. Different combinations of materials, flowfield designs and fabrication techniques have been developed for FPPs to achieve the aforementioned functions efficiently, with the main scope of obtaining high performance and economic advantages.
Introduction to Flow Field PlatesThe FPP, also known as the monopolar plate (in a single cell) and bipolar plate (BPP, when used in a stack), is one of the many important components of PEM fuel cell stacks as it supplies fuel and oxidant to the MEA, removes water, collects produced current and provides mechanical support for the single cells in the stack (Figure 1)
AbstractThis review describes some recent developments in the area of flow field plates (FFPs) for proton exchange membrane fuel cells (PEMFCs). The function, parameters and design of FFPs in PEM fuel cells are outlined and considered in light of their ...
