Abstract:
A method for absorbing and releasing hydrogen comprises applying repeatedly hydrogen pressurization and depressurization to a hydrogen storage metal alloy of a body-centered cubic structure-type phase exerting a two-stage or inclined plateau characteristic in a hydrogen storage amount vs hydrogen pressure relation in an appropriate fashion to absorb and release hydrogen. At least at one stage during the release of hydrogen, the temperature (T2) of the above-mentioned hydrogen storage metal alloy is made higher than the temperature (T1) of the hydrogen storage metal alloy during the hydrogen absorption process (T2>T1). This enables the release and utilization of occluded hydrogen at a low-pressure plateau region or an inclined plateau lower region.
Abstract:
A process for producing hydrogen storage metal alloys having a body-centered cubic structure-type main phase enabling the adsorption and desorption of hydrogen is provided which comprises the steps of: (1) melting a starting alloy brought to a predetermined element ratio to form a uniform heat (melting step), (2) keeping the homogenized alloy heat at a temperature within a range just below the melting point of the alloy for a predetermined time (heat treatment), and (3) rapidly cooling the alloy after the heat treatment (quenching step).
Abstract:
A process for producing hydrogen storage metal alloys having a body-centered cubic structure-type main phase enabling the adsorption and desorption of hydrogen is provided which comprises the steps of: (1) melting a starting alloy brought to a predetermined element ratio to form a uniform heat (melting step), (2) keeping the homogenized alloy heat at a temperature within a range just below the melting point of the alloy for a predetermined time (heat treatment), and (3) rapidly cooling the alloy after the heat treatment (quenching step).
Abstract:
A method for absorbing and releasing hydrogen comprises applying repeatedly hydrogen pressurization and depressurization to a hydrogen storage metal alloy of a body-centered cubic structure-type phase exerting a two-stage or inclined plateau characteristic in a hydrogen storage amount vs hydrogen pressure relation in an appropriate fashion to absorb and release hydrogen. At least at one stage during the release of hydrogen, the temperature (T2) of the above-mentioned hydrogen storage metal alloy is made higher than the temperature (T1) of the hydrogen storage metal alloy during the hydrogen absorption process (T2>T1). This enables the release and utilization of occluded hydrogen at a low-pressure plateau region or an inclined plateau lower region.
Abstract:
A method for absorbing and releasing hydrogen comprises applying repeatedly hydrogen pressurization and depressurization to a hydrogen storage metal alloy of a body-centered cubic structure-type phase exerting a two-stage or inclined plateau characteristic in a hydrogen storage amount vs hydrogen pressure relation in an appropriate fashion to absorb and release hydrogen. At least at one stage during the release of hydrogen, the temperature (T2) of the above-mentioned hydrogen storage metal alloy is made higher than the temperature (T1) of the hydrogen storage metal alloy during the hydrogen absorption process (T2>T1). This enables the release and utilization of occluded hydrogen at a low-pressure plateau region or an inclined plateau lower region.
Abstract:
A fuel cell hydrogen recovery system comprises a primary hydrogen absorbing tank adapted for storing hydrogen discharged from a fuel cell and a secondary hydrogen absorbing tank adapted for storing part of hydrogen that is supplied to the fuel cell. The primary hydrogen absorbing tank and the secondary hydrogen absorbing tank are provided so that heat can be exchanged therebetween. Part of hydrogen that is supplied to the fuel cell is supplied to the secondary hydrogen absorbing tank, so that the primary hydrogen absorbing tank is heated by hydrogen absorbing heat generated when hydrogen is absorbed therein, whereby hydrogen absorbed in the primary hydrogen absorbing tank can be re-supplied to the fuel cell.
Abstract:
A hydrogen storage apparatus M stores a liquid hydrogen tank 1, hydrogen filling passage 3 that fills liquid hydrogen in to the liquid hydrogen tank, a degassing passage 4 provided with a relief valve V1 that opens when the pressure of hydrogen gasified in the liquid hydrogen tank reaches a predetermined level, and a hydrogen occlusive tank 2 that accommodates a hydrogen occlusive alloy 21 for storing the gasified hydrogen. When liquid hydrogen is being filled into the liquid hydrogen tank 1, the pressure in the hydrogen occlusive tank 2 is lowered using a duct 51, a cooling fan 52, and a conduit 54 for cooling the hydrogen occlusive tank 2. Accordingly, the filling time is shortened and the fuel efficiency is improved.
Abstract:
An apparatus and a method of heat exchange of a liquid fuel type fuel cell system. The apparatus includes: an electricity generating unit to generate electricity when a fuel is supplied to an anode and oxidizer is supplied to a cathode; a first flow path unit connected to an outlet of the cathode; a second flow path unit connected to an inlet of the anode; a heat exchanging unit to exchange thermal energy between fluids passing through the first flow path unit and the second flow path unit; a third flow path unit connected to the inlet on an anode and bypassing the heat exchanging unit; and a first valve to control flow ratios of fluids passing through the second flow path unit and the third flow path unit. The method of heat exchange includes: sensing the temperature of the electricity generating unit; and controlling a flow path of the third flow path unit depending on the temperature of the electricity generating unit.
Abstract:
A hydrogen supplying apparatus mounted on an electric vehicle. The electric vehicle is driven by electricity generated at a fuel cell by an electrochemical reaction between hydrogen stored in a hydrogen storage tank and oxygen. The hydrogen supplying apparatus includes: a hydrogen supply passage for supplying hydrogen from the hydrogen storage tank to the fuel cell; a bypass passage arranged in parallel with the hydrogen supply passage and for supplying hydrogen to the fuel cell; a purifier provided in the bypass passage, the purifier purifying hydrogen to be supplied to the fuel cell; and a switch valve selectively switching the hydrogen supply passage and the bypass passage.
Abstract:
A fuel cell system having a fuel cell consuming the hydrogen stored in the high-pressure hydrogen tank as fuel gas, a hydrogen supply line connecting the high-pressure hydrogen tank to the fuel cell, a primary decompressing means provided on the hydrogen supply line, a secondary decompressing means provided in the downstream side of the primary decompressing means on the hydrogen supply line, a hydrogen storage alloy tank saving a hydrogen storage alloy and thermal-exchangeably connected to the fuel cell, a hydrogen pipe connected between the primary decompressing means and the secondary decompressing means, and supplied for hydrogen transfer between the hydrogen supply line and the hydrogen storage alloy tank is provided, and a controlling means for introducing the hydrogen of the first prescribed pressure into the hydrogen storage alloy tank from the hydrogen supply line through the hydrogen pipe during the warm-up of the fuel cell.