摘要:
The invention relates to a system and method of operating alkaline exchange membrane fuel cells in a bipolar configuration. The system (400) may include a first fuel cell (300A) and a second fuel cell (300B) adjacent to the first fuel cell. Each of the first and second fuel cells may include: a cathode configured to generate hydroxide ions from water, oxygen and electrons, an anode configured to generate water and electrons from the hydroxide ions and hydrogen received from a hydrogen source, and an alkaline exchange membrane configured to transfer the hydroxide ions from the cathode to the anode, and to transfer water from a vicinity of the anode to a vicinity of the cathode. The first fuel cell (300A) and a second fuel cell (300B) are connected by a porous bipolar plate (430A) positioned inbetween. A pressure profile across the first bi-polar plate may drop from higher level near the anode of the first fuel cell (300A) to lower level near the cathode of the second fuel cell (300B) so that water may be transferred from the anode of the first fuel cell (300A) to the cathode of the second fuel cell (300B).
摘要:
Disclosed is a process for making a gas diffusion electrode that comprises an electrically conductive substrate, a gas diffusion layer (GDL) and an active layer (AL). The process comprises forming the GDL and/or the AL by pressing and/or rolling a mass obtained by subjecting electrically conductive carbon material and polymeric binder and, in the case of the AL, electroactive catalyst to high energy mixing in a liquid medium, followed by the separation of solid matter from the liquid medium and, optionally, drying of the separated solid matter.
摘要:
Fuel cells (38) have passageways (83, 84) that provide water through one or both reactant gas flow field plates (75, 81 ) of each fuel cell, whereby the fuel cell is cooled evaporatively. The water passageways may be vented by a porous plug (not shown), or by a microvacuum pump (89). A condenser (59) may have a reservoir (64); the condenser (59) may be a vehicle radiator. A highly water permeable wicking layer (90) is disposed adjacent to one or both water passageways (83, 84) which exist between individual fuel cells (38). The passageways may be flow-through passageways (83) (Fig. 5) or they may be interdigitated passageways (83a, 83b) (Fig. 6) in order to increase the flow of water-purging air through the wicking layer (90) utilized to clear the stack of water during shutdown in cold environments. The inlet interdigitated channels (83c, 83d) may be only partially blocked at their outlet ends such as by a protrusion (104) or a hole (106) in order to ensure that any gas entering the inlet coolant passageways (83c, 83d) will not accumulate at the outlet end (101 ) of the inlet coolant passageways.
摘要:
Die Erfindung betrifft ein Verfahren zur Beladung eines flächigen Bauelements einer Brennstoffzelle mit Katalysatormaterial, wobei man ein im wesentlichen flächiges Bauelement der Brennstoffzelle bereitstellt, ein Katalysatormaterial auf zumindest eine Oberfläche des flächigen Bauelements aufbringt, wobei das Katalysatormaterial ein Klebemittel zur Verbesserung der Haftung des Katalysatormaterials an der Oberfläche des flächigen Bauelements umfasst. Das erfindungsgemäße Katalysatormaterial besteht aus einer wässrigen Suspension, die 30 bis 50 Gew.% Katalysatorpulver, 10 bis 30 Gew.% eines mehrwertigen Alkohols und 0,5 bis 5 Gew.% Fasermaterialien umfasst, und ist dadurch gekennzeichnet, dass die wässrige Suspension außerdem 1 bis 10 Gew.% eines physikalisch aktivierbaren Klebstoffs umfasst.
摘要:
A fuel cell stack (31) includes a plurality of fuel cells (9) each having an electrolyte such as a PEM (10), anode and cathode catalyst layers (13, 14), anode and cathode gas diffusion layers (16, 17), and water transport plates (21, 28) adjacent the gas diffusion layers. The cathode diffusion layer of cells near the cathode end (36) of the stack have a high water permeability, such as greater than 3x10-4 g/(Pa s m) at about 80°C and about 1 atmosphere, whereas the cathode gas diffusion layer in cells near the anode end (35) have water vapor permeance greater than 3x10-4 g/(Pa s m) at about 80°C and about 1 atmosphere. In one embodiment, the anode gas diffusion layer of cells near the anode end (35) of the stack have a higher liquid water permeability than the anode gas diffusion layer in cells near the cathode end; a second embodiment reverses that relationship.
摘要翻译:燃料电池堆(31)包括多个燃料电池(9),每个燃料电池均具有诸如PEM(10),阳极和阴极催化剂层(13,14)的电解质,阳极和阴极气体扩散层(16,17) 和与气体扩散层相邻的水输送板(21,28)。 在堆叠的阴极端(36)附近的电池的阴极扩散层在约80℃和约1个大气压下具有高的透水性,例如大于3×10-4g /(Pa·sm),而阴极气体扩散 在阳极端(35)附近的单元中的层在约80℃和约1个大气压下具有大于3×10 -4 g /(Pa·sm)的水蒸气渗透率。 在一个实施例中,在堆叠的阳极端(35)附近的电池的阳极气体扩散层在靠近阴极端的电池中具有比阳极气体扩散层更高的液体水渗透性; 第二个实施例反转了这种关系。
摘要:
A fuel cell includes an electrode assembly having an electrolyte between a cathode catalyst and an anode catalyst, and a flow field plate having a channel for delivering a reactant gas to the electrode assembly. The flow field plate includes a channel having a channel inlet. A porous diffusion layer is located between the electrode assembly and the flow field plate. The porous diffusion layer includes a first region near the channel inlet and a second region downstream from the first region relative to the channel inlet. The first region includes a filler material that partially blocks pores of the first region such that the first region has a first porosity and the second region has a second porosity that is greater than the first porosity.
摘要:
A flow field plate for use in a fuel cell includes a porous, wettable plate body. A plurality of flow channels are arranged on the body such that an inlet portion of a first flow channel is adjacent an outlet portion of a second flow channel. Moisture from a fluid in the outlet portion of the second flow channel can move through the body of the porous, wettable plate from the outlet portion of the second flow channel toward the adjacent inlet portion of the first flow channel.