摘要:
Disclosed is a fuel cell with enhanced mass transfer characteristics in which a highly hydrophobic porous medium, which is prepared by forming a micro-nano dual structure in which nanometer-scale protrusions with a high aspect ratio are formed on the surface of a porous medium with a micrometer-scale roughness by plasma etching and then by depositing a hydrophobic thin film thereon, is used as a gas diffusion layer, thereby increasing hydrophobicity due to the micro-nano dual structure and the hydrophobic thin film. When this highly hydrophobic porous medium is used as a gas diffusion layer for a fuel cell, it is possible to reduce water flooding by efficiently discharging water produced by an electrochemical reaction of the fuel cell and to improve the performance of the fuel cell by facilitating the supply of reactant gases such as hydrogen and air (oxygen) to a membrane-electrode assembly (MEA).
摘要:
A failure diagnosis apparatus that includes an alternating current (AC) absorption unit that is connected to the fuel cell stack and switched based on an applied AC signal to enable a current from the fuel cell stack to flow. In addition, an AC signal generator is configured to generate the AC signal and supply the generated AC signal to the AC absorption unit. As the current from the fuel cell stack is absorbed by the AC absorption unit based on an alternating signal, a stack current input into a diagnosis processing unit includes an AC component, thus the diagnosis processing unit may diagnose fuel cell stack failure by analyzing a frequency of the AC component.
摘要:
A fuel cell system and a method of controlling the fuel cell system are provided. The fuel cell system includes at least one bypass valve that is disposed between a passage in an inlet of a fuel cell stack and a bypass passage that is branched from the passage within the inlet and that is connected to a discharge port of the fuel cell stack. In addition, a controller bypasses air supplied from an air blower to the discharge port by adjusting an opening degree of the bypass valve.
摘要:
Disclosed are a safety system of a fuel cell vehicle and a control method for the safety system. A safety system of a fuel cell vehicle using a fuel cell and a high voltage battery as a power source may include: a power switch disposed on a power wire connecting the power source and a power load to each other; an insulation resistance measuring device measuring an insulation resistance between the power wire and a chassis; and a controller controlling an operation of the power switch based on a measured insulation resistance measured by the insulation resistance measuring device. When the measured insulation resistance is equal to or less than a reference resistance, the controller enters a safe mode and the power switch is turned off to thereby block power supplied to the power load.
摘要:
Disclosed is a fuel cell with enhanced mass transfer characteristics in which a highly hydrophobic porous medium, which is prepared by forming a micro-nano dual structure in which nanometer-scale protrusions with a high aspect ratio are formed on the surface of a porous medium with a micrometer-scale roughness by plasma etching and then by depositing a hydrophobic thin film thereon, is used as a gas diffusion layer, thereby increasing hydrophobicity due to the micro-nano dual structure and the hydrophobic thin film. When this highly hydrophobic porous medium is used as a gas diffusion layer for a fuel cell, it is possible to reduce water flooding by efficiently discharging water produced by an electrochemical reaction of the fuel cell and to improve the performance of the fuel cell by facilitating the supply of reactant gases such as hydrogen and air (oxygen) to a membrane-electrode assembly (MEA).
摘要:
The present invention provides a fuel cell separator with a gasket manufactured by integrally forming a gasket on one side of a separator; independently injection molding a frame gasket on a frame such that a first airtight portion covers the entire surface of the frame to maintain the shape of the frame gasket and a second airtight portion projects upward and downward from both ends of the first airtight portion; and bringing the first airtight portion of the frame gasket into contact with the other side of the separator with the gasket formed on one side thereof. To create a fuel cell stack in certain embodiments, the invention stacks the second airtight portion of the frame gasket on another second airtight portion of an adjacent unit cell with a membrane-electrode assembly interposed therebetween.
摘要:
A diagnostic and heat management system for a fuel cell stack is provided herein that includes a diagnostic control analyzer that diagnoses and analyzes a state of the fuel cell stack by measuring a voltage and a current of the fuel cell stack. Also, an AC signal generator generates a diagnostic AC signal, and an AC component driving element that is included in an AC component in a current of the fuel cell stack. Additionally, a termoelement is driven as a heat absorbing device when a temperature of the AC component driving element is equal to or greater than a predetermined temperature and is driven as a heat emitting device when a temperature of the AC component driving element is less than a predetermined temperature, in order to manage heat generation in the AC component driving element.
摘要:
A failure diagnosis apparatus that includes an alternating current (AC) absorption unit that is connected to the fuel cell stack and switched based on an applied AC signal to enable a current from the fuel cell stack to flow. In addition, an AC signal generator is configured to generate the AC signal and supply the generated AC signal to the AC absorption unit. As the current from the fuel cell stack is absorbed by the AC absorption unit based on an alternating signal, a stack current input into a diagnosis processing unit includes an AC component, thus the diagnosis processing unit may diagnose fuel cell stack failure by analyzing a frequency of the AC component.
摘要:
To diagnose a fault of a fuel cell stack, an alternating current having a first optimal frequency of a first frequency domain to diagnose a drop in cell voltage and an alternating current having a second optimal frequency of a second frequency domain to diagnose a cause of the drop in cell voltage are supplied to the fuel cell stack are provided. A distortion rate is then calculated based on voltage of the fuel cell stack according to the alternating current of the first optimal frequency, and the drop in cell voltage is diagnosed based on the calculated distortion rate. Also, impedance is calculated based on voltage and a current of the fuel cell stack according to the alternating current of the second optimal frequency and amount of water is calculated based on the calculated in the fuel cell stack, and the cause of the drop in cell voltage is diagnosed based on the calculated impedance and amount of water.
摘要:
The present invention features a fuel cell stack that preferably includes an electricity generating assembly having a plurality of unit cells that are suitably disposed one after another; a pair of end plates pressedly disposed respectively at upper and lower ends of the electricity generating assembly; and a joining device suitably engaging the end plates by a rope, where pressure is applied to the electricity generating assembly by means of tension of the rope, and the length and tension of the rope is suitably controlled.