WO2018154050A1

WO2018154050A1 - Hydrogen storage and supply system

Info

Publication number: WO2018154050A1
Application number: PCT/EP2018/054504
Authority: WO
Inventors: Michael Francis Levy; Jorn OUBRAHAM; Carsten Pohlmann; Jean-Baptiste Dementhon
Original assignee: Aaqius & Aaqius Sa
Priority date: 2017-02-24
Filing date: 2018-02-23
Publication date: 2018-08-30
Also published as: FR3063333A1; CN110546423B; CN110546423A; FR3063333B1; TW201841822A

Abstract

A system for storing and supplying hydrogen to a hydrogen usage unit (130), comprising: -a first hydrogen storage tank (110) comprising a first material (111) for storage of hydrogen by sorption, -a second hydrogen storage tank (120) comprising a second material (121) for reversible storage of hydrogen by sorption, -a hydrogen outlet (1101) from the first tank to the second tank and/or the hydrogen usage unit, -a hydrogen outlet (1201) from the second tank to the hydrogen usage unit, the first material having, for one and the same temperature and one and the same level of hydrogen load, a desorption equilibrium pressure which is strictly below that of the second material, so as to allow the first tank to supply a first hydrogen stream to the usage unit, and to allow the second tank to supply a second hydrogen stream to the usage unit, wherein the second stream supplements and/or replaces the first stream.

Description

HYDROGEN STORAGE AND SUPPLY SYSTEM

Field of the Invention The invention relates to a system for storing and supplying hydrogen. The invention also relates to an associated method.

State of the art

There are hydrogen storage and supply systems. These systems may comprise at least one solid material for storing the hydrogen by adsorption or absorption.

These systems must obey many constraints, related to the use for which they are intended, for example a use in a motor vehicle, for example a fuel cell.

Sufficient storage capacity and throughput to ensure the intended use are required. However, a large amount of hydrogen can pose safety problems, especially when the system must be able to operate at high temperatures. One possibility is to design the system by seeking to limit the pressures to which it may be subjected, for example at high temperature. However, this low pressure operation poses problems of system efficiency, and may even render it inoperative at low temperatures.

SUMMARY OF THE INVENTION An object of the invention is to provide a system for solving at least one of the above disadvantages. An object of the invention in particular to provide a system that can be both safe and functional.

For this purpose, there is provided a system for storing and supplying hydrogen to a unit for using hydrogen, comprising:

a first hydrogen storage tank comprising a first sorption hydrogen storage material,

a second hydrogen storage tank comprising second reversible sorption hydrogen storage material, - a hydrogen outlet from the first tank to the second tank and / or the hydrogen utilization unit,

a hydrogen outlet from the second reservoir to the hydrogen utilization unit,

the first material having, for the same temperature and the same hydrogen loading rate, a desorption equilibrium pressure strictly lower than that of the second material, so as to allow the first reservoir to provide a first hydrogen flow to the unit of use, and the second tank to provide a second flow of hydrogen to the use unit, the second stream complementing and / or replacing the first flow.

These characteristics are advantageously supplemented by the following characteristics, taken alone or in any of their technically possible combinations:

the system is configured to allow the first reservoir to supply the first flow to the second reservoir in order to recharge the second reservoir with hydrogen,

the first material and / or the second material is adapted to form a hydride, preferably a metal hydride, the second reservoir is, for example, configured to supply, at ambient temperature, the second flow of hydrogen so as to allow operation of the utilization unit,

the hydrogen outlet from the first reservoir to the second reservoir and / or the hydrogen utilization unit is provided with a non-return valve,

the hydrogen utilization unit comprises a fuel cell and / or an exhaust gas treatment system and / or a hydrogen engine,

the at least one second reservoir comprises a plurality of second reservoirs, preferably adapted to alternately supply the second flow,

for each second reservoir, the system comprises a hydrogen outlet from the second reservoir to the hydrogen utilization unit and a hydrogen inlet from the second reservoir, the inlet being at least partially distinct from the outlet, control means configured to implement the method

The invention further relates to a method of supplying hydrogen to a hydrogen consumption unit, the method being implemented by the system according to the invention. characteristics are advantageously supplemented by the following characteristics, taken alone or in any of their technically possible combinations:

- temperature rise of the first material until an operating temperature is reached,

before and / or during the rise in temperature, supplying the second reservoir of the second stream of hydrogen to the utilization unit instead of the first flow, - Once the operating temperature reached by the first material, supplying the first reservoir of the first flow of hydrogen, and preferably stopping the supply of the second flow,

- supply by the first reservoir of the first flow of hydrogen to the unit of use,

- supply by the second reservoir of the second hydrogen stream to the use unit in addition to the first flow,

reloading hydrogen of the second reservoir by the first reservoir,

at the end of at least one step of supplying the second reservoir of the second hydrogen stream, the second reservoir has a sufficient loading to implement a new step of supplying the second hydrogen stream.

Brief description of the figures

Other features and advantages of the invention will become apparent in the following description of an embodiment. In the accompanying drawings:

FIG. 1 represents examples of system according to exemplary embodiments of the invention,

FIG. 2 represents an exemplary system according to an exemplary embodiment of the invention,

FIG. 3 represents an exemplary behavior of the system during the implementation of an exemplary method according to an exemplary embodiment of the invention,

FIG. 4 represents an exemplary behavior of the system during the implementation of an exemplary method according to an exemplary embodiment of the invention, FIG. 5 represents the behavior of an exemplary material of a system according to an exemplary embodiment of the invention,

FIG. 6 represents the behavior of examples of materials of a system according to an exemplary embodiment of the invention, and

FIG. 7 represents the behavior of the examples of materials of FIG. 6.

Detailed description of the invention

Hydrogen storage and / or supply system General presentation

Referring to Figures 1 and 2, there is described a system 100 for storing and / or supplying hydrogen.

The system 100 is for example a hydrogen storage and / or supply system, for example at least one hydrogen utilization unit 130. The system 100 is for example a storage and / or supply system for hydrogen. hydrogen for a device.

The system 100 is for example a system for storing and / or supplying hydrogen for a vehicle. The vehicle is for example a motor vehicle. The motor vehicle is for example a vehicle with an electric motor, for example powered by a fuel cell. The motor vehicle is for example a vehicle with a heat engine.

The system 100 is for example a system for storing and / or supplying hydrogen for a stationary device. The stationary device is for example an electricity supply unit, for example a generator, for example a supply unit emergency and / or emergency electricity, for example a lighting unit, for example lighting a building. The electricity supply unit is for example portable.

The system 100 comprises for example at least one first hydrogen storage tank 1 10, for example a plurality of first tanks 1 10. The first tank 1 10 comprises for example a first material 1 1 1 for storing hydrogen.

Unless otherwise stated, the terms first, second and other ordinals are used simply to list elements and do not prejudge an order between them.

The first material 1 1 1 is for example a hydrogen storage material, for example by sorption.

Sorption is the process by which a substance is adsorbed or absorbed on or in another substance. By absorption is meant the ability of a material to retain molecules in its volume. By adsorption is meant the ability of a material to retain molecules on its surface.

The first material 11 may be a solid material or in the form of a gel. The first material 11 may be a reversible storage material. The first material 11 may be a storage material by adsorption and / or absorption. The first material 11 may be a storage material by hydriding and / or dehydriding.

The system 100 comprises for example at least one second tank 120 for storing hydrogen. The second tank 120 comprises for example a second material 121 for storing hydrogen. The second material 121 is, for example, a reversible storage material for hydrogen, for example by sorption.

The second material 121 may be a solid material or in the form of a gel. The second material 121 may be a storage material by adsorption and / or absorption. The second material 121 may be a storage material by hydriding and / or dehydriding. By reversible is meant that an initially loaded material which has been at least partially discharged may be at least partially recharged in the medium in which the material is placed, for example a medium consisting of gaseous dihydrogen.

It can conventionally be defined the partial reloading as being a reloading at a pressure less than or equal to 200 bar, in a temperature range suitable for reloading the material, for example at an optimum temperature for reloading the material at the pressure in question, for example so as to achieve a given load rate, for example 50%, for example so as to increase the load ratio by a given percentage for example by at least 10%.

The system comprises for example a hydrogen outlet 101 of the first reservoir to the second reservoir and / or the hydrogen utilization unit,

The system comprises, for example, a hydrogen outlet 1201 from the second tank to the unit for using hydrogen,

The first material 1 1 1 differs for example from the second material 121 by its thermodynamic properties for the sorption of hydrogen.

The first material 1 1 1 has for example, for the same temperature and the same hydrogen loading rate, a desorption equilibrium pressure strictly lower than that of the second material, so as to allow the first reservoir to provide a first flow of hydrogen to the unit of use, and the second tank to provide a second stream of hydrogen to the use unit, the second stream complementing and / or replacing the first stream.

It is thus possible to realize a secure system with the first tank, which can check pressure limit criteria, while presenting with the second tank a more reactive unit. By the same temperature and the same charge rate, we mean a given temperature and a given charge rate.

The same temperature is for example between 40 ° C and 60 ° C, for example equal to 50 ° C.

The same charge rate is for example between 40% and 60%, for example substantially equal to 50%. The charge rate is for example expressed as a percentage. By charge rate is meant the ratio of the mass of hydrogen introduced into the system to the maximum mass of hydrogen that the system can hold, at the given temperature.

By convention, it can be defined that the maximum mass, and therefore the charge rate, is calculated at a reference pressure, for example 200 bar.

The first material 11 1 has, for example, a hydrotreating equilibrium pressure at 50 ° C., at a loading rate of 50% at 50 ° C., which is strictly lower than that of the second material 121.

By desorption equilibrium pressure of a material at a given temperature and at a given charge rate is meant the minimum gas pressure exerted on the material for which there is no release of hydrogen. At an infinitesimally lower pressure, hydrogen is released.

By absorption equilibrium pressure or adsorption of a material at a given temperature and at a given filler rate means the maximum gas pressure exerted on the material for which there is no absorption or hydrogen adsorption. At an infinitesimally higher pressure, hydrogen is absorbed or adsorbed.

The desorption equilibrium pressure is, for example, a dehydration equilibrium pressure.

The first material 1 1 1 has, for example for the same temperature and for the same charge rate, an equilibrium pressure of desorption and / or absorption and / or adsorption, for example of hydriding and / or dehydriding, strictly less than that of the second material 121 at least 1 mbar, for example at least 10 mbar, for example at least 100 mbar, for example at least 1 bar.

For example, the system is configured and / or the first tank and the second tank are arranged and / or the first material and the second material are arranged to allow, for example in a first operating position, the first tank 1 10 to supply the first hydrogen stream to the utilization unit 130, for example when the system is in operation.

For example, the system is configured and / or the first tank and the second tank are arranged and / or the first material and the second material are arranged to allow, for example in the first operating position, the second tank 120 of supplying the second stream of hydrogen to the utilization unit 130, the second stream for example completing and / or replacing the first stream, for example when the system is in operation.

It is thus possible to realize a secure system with the first tank, which can check pressure limit criteria, while presenting with the second tank a more reactive unit.

This unit can for example allow the system to start when the temperature is not sufficient for the first tank. In particular, the second tank 120 is for example adapted to supply the second stream of hydrogen so as to allow the operation of the unit of use, for example in addition to the first stream of hydrogen, for example in the absence the first stream of hydrogen, for example at room temperature, for example at a room temperature of less than or equal to 15 ° C, for example less than or equal to 10 ° C, for example less than or equal to 0 ° C, for example lower or at -10 ° C, for example less than or equal to -20 ° C. It is thus possible to quickly start the system despite low temperatures, for example do not not suitable for the first tank, for example while heating the first tank.

Alternatively in addition, such a unit can quickly provide a surplus of hydrogen when the demand increases sharply.

It is thus possible to obtain a system operating efficiently at lower pressures, which makes it possible to reduce the thickness of the walls of the tank and to improve its density and / or its gravimetric storage density.

In particular, it is thus possible to obtain a high equilibrium pressure in the second reservoir which ensures the supply of hydrogen at a high pressure and / or a high flow rate and / or a high availability of hydrogen within the second reservoir. material and / or makes it possible to have a low operating temperature and / or decreases the risks of vacuum at low temperature and therefore the risks of contamination of the materials.

It is also possible to dispense with the preheating device of the second tank, or to limit the dimensions of the preheating device, or to limit its use. This is particularly advantageous because electric batteries that would operate at low temperatures can occupy a large space and / or have a large mass. This also simplifies the system because the constraints related to preheating are lower. This still allows to have quickly, or even immediately, a significant power unlike the limited powers during preheating.

It is also possible to dispense with overpressure release valve in the first tank, which is subjected to low pressure, or to reduce the leakage associated with the valve. It is also possible to do without valve or pressure relief valve in the second tank, which is smaller in size, can be designed with increased resistance, or reduce the leakage associated with the valve. It is so possible to reduce the hydrogen losses associated with such valves and / or the associated safety risks when hydrogen is released, for example if an element from the reservoir blocks the valve and / or to limit this procedure to an emergency situation.

It is thus possible not to be subject to minimum and / or maximum temperature limitations for the system without this entailing operational or safety problems.

It is also possible to modify the tank design with respect to very stable tanks sized to be very resistant to high pressures. This then makes it possible to increase the volumetric and / or gravimetric storage capacity, and / or the efficiency and heat transfer because there is less material to heat, and / or a reduction in the weight of the tank and / or other elements associated with the reservoir such as connecting means which no longer have to withstand high pressures.

The system 100 is for example configured so as to reload the second tank 120 with the first tank 1 10, when the system is in operation. The system is for example configured so as to allow, for example in a second operating position, the first tank 1 10 to provide the first flow to the second tank 120 in order to recharge the second tank 120 hydrogen.

It is thus possible alternatively to use the second tank 120 when the first tank 1 1 0 is not able or not enough to ensure the hydrogen demand, then to recharge the second tank 120 during stationary phases or quieter , in anticipation of a new use of the second tank 120.

Unit of use of hydrogen The system 100 comprises for example at least one hydrogen utilization unit 130, for example a plurality of hydrogen utilization units.

The at least one hydrogen utilization unit 130 is or includes, for example, a hydrogen consumption unit.

The at least one hydrogen utilization unit 130 is or comprises, for example, a system for treating gases from an engine, for example at an exhaust line.

The at least one hydrogen utilization unit 130 is or includes, for example, a fuel cell, for example a proton exchange membrane fuel cell.

The at least one hydrogen utilization unit 130 may comprise the fuel cell and / or an electric motor adapted to be powered by the fuel cell. The at least one unit for using hydrogen is or comprises, for example, a hydrogen engine, for example a heat engine adapted to be supplied with hydrogen, for example an internal combustion engine and / or a mixed engine.

The system is for example configured so that the first tank 1 10 and / or the second tank 120 can supply the hydrogen utilization unit with hydrogen. The unit for using hydrogen has, for example, an inlet pressure greater than or equal to 1.5 bar, for example 2.5 bar, for example 5 bar, for example 10 bar.

Fluid connections

The first tank 1 10 and / or the second tank 120 and / or the hydrogen utilization unit 130 are for example connected fluidically, for example as illustrated in FIG.

By "fluidic connection between two elements" means any means of fluid communication adapted to put in fluid communication the two elements. The means of fluid communication can for example include one or more pipes and / or one or more valves.

For example, the first tank 1 10 and the second tank 120 are fluidly connected, for example so that the fluid connection can be selectively blocked. For example, the second tank 120 and the hydrogen utilization unit 130 are fluidly connected, for example so that the fluid connection can be selectively blocked. For example, the first reservoir 1 10 and the hydrogen utilization unit 130 are fluidly connected, for example, so that the fluid connection can be selectively blocked.

The system 100 comprises, for example, the hydrogen outlet 1 101 from the first tank 1 10 to the second tank 120 and / or the hydrogen utilization unit 130. The outlet 1 101 is for example provided with means for blocking the water. output 1 102, which comprise for example a valve, for example a solenoid valve, are for example movable at least between an open position and a closed position. In the open position, the outlet 1 101 allows the flow of hydrogen from the first tank 1 10. In the closed position, the outlet 1 101 does not allow the flow of hydrogen from the first tank 1 10. The output 1 101 comprises for example one or more pipes and / or one or more walls. The outlet 101 may be provided with a non-return valve, for example to prevent any return of hydrogen from the second tank 120 and / or the hydrogen utilization unit 130.

The system 100 comprises, for example, the outlet 1201 of hydrogen from the second tank 120 to the hydrogen utilization unit 130. The outlet 1201 forms, for example, a hydrogen inlet of the second tank 120 from the first tank 1 10. It is then for example the pressure which determines whether the behavior of the output is that of an output or an input. Alternatively or in addition, the hydrogen inlet of the second tank 120 from the first tank 1 10 may be at less partially distinct from exit 1201. The output 1201 is for example provided with output and / or input blocking means 1202, which comprise for example a valve, for example a solenoid valve, are for example movable at least between an open position and a closed position. In the open position, the outlet 1201 allows the flow of hydrogen from and / or to the second tank 120. In the closed position, the outlet 1201 does not allow the flow of hydrogen from and / or to the second tank 120. The output 1201 comprises for example one or more pipes and / or one or more walls.

The system 100 comprises, for example, a hydrogen inlet 1301 of the hydrogen utilization unit 130 from the first tank 1 10 and / or the second tank 120. The first inlet 1301 is for example provided with means for blocking the water. 1302, which comprise for example a valve, for example a solenoid valve, are for example movable at least between an open position and a closed position. In the open position, the inlet 1301 allows the flow of hydrogen to the consumption unit 130. In the closed position, the inlet 1301 does not allow the flow of hydrogen to the consumption unit 130. The inlet 1301 may be provided with dosing means, the inlet blocking means 1302 forming the dosing means or the dosing means being distinct from the input blocking means 1302. The inlet 1301 comprises for example one or several pipes and / or one or more walls. The inlet 1301 may be provided with a non-return valve, for example to prevent any return of hydrogen from the hydrogen utilization unit 130.

The output 1 101 and / or the output 1201 and / or the input 1301 are for example in contact at a connection 1 103.

The second tank 120 comprises, for example, hydrogen recharging means that are distinct from the first tank 1. The separate hydrogen charging means comprise, for example, a dedicated inlet, comprising, for example, one or more pipes. and / or one or more walls. The dedicated input is for example provided with dedicated blocking means, which comprise for example a valve, for example a solenoid valve, are for example movable at least between an open position and a closed position.

The first tank 1 10 is for example fluidly connected to the hydrogen utilization unit 130 without necessarily passing through the second tank 120. Alternatively or in addition, the second tank 120 is for example disposed between the first tank 1 10 and the hydrogen utilization unit 130, the first tank 1 10 and the hydrogen utilization unit 130 being fluidly connected via the second tank 120.

Reservoir Removability The first reservoir 1 10 is for example removable. The second tank 120 is for example irremovable. Removable means what can be replaced without disassembling the rest of the system that would make it non-functional. By irremovable means that can not be replaced without disassembling the rest of the system that would make it non-functional.

The fluid connection between the first and second tanks 1 10 and 120 therefore allows for example to recharge the second tank 120 without stopping the operation of the device, for example the vehicle, or in the case where the second tank 120 is irremovable.

It is possible to dimension separately the first tank of the second tank, which allows a simplification of the sizing of the system and compactness improve for the first tank, which is particularly interesting if it is removable. In addition, the first reservoir can be sized to be stored at elevated temperatures.

Plurality of second tanks The system 100 may comprise a plurality of second reservoirs 120a 120b, for example as shown in FIG. 2. The first reservoir 1 10 and / or the second reservoirs 120a 120b and / or the hydrogen utilization unit 130 are for example connected fluidically, for example as illustrated in FIG.

The system 100 comprises, for example, the hydrogen outlet 1101 from the first tank 1 10 to the second tank 120a and / or the second tank 120b and / or the hydrogen utilization unit 130. The outlet 101 is by example provided with the first output blocking means 1 102.

For each second tank 120a, respectively 120b, the system 100 comprises, for example, an outlet 1201a, respectively 1201b, of hydrogen from the second tank 120a, respectively 120b, towards the hydrogen utilization unit 130.

For each second tank 120a, respectively 120b, the system 100 comprises for example an inlet 1203a, respectively 1203b, of hydrogen from the second tank 120a, respectively 120b, from the first tank 1 10. These entries 1203a and 1203b thus allow the second tanks to receive hydrogen from the first tank 1 10. The inlet 1203a, respectively 1203b, is for example at least partially separate from the output 1201a, respectively 1201b. The input 1203a, respectively 1203b and the output 1201a, respectively 1201b, comprise for example a common portion.

The output 1201a, respectively 1201b, is provided for example with output blocking means 1202a, respectively 1202b, which comprise for example a valve, for example a solenoid valve, are for example movable at least between an open position and a closed position . In the open position, the outlet 1202a, respectively 1202b, allows the flow of hydrogen from the second tank 120a, respectively 120b, for example to the hydrogen utilization unit 130. In the closed position, the outlet 1201 a, respectively 1201b, do not does not allow the flow of hydrogen from and / or to the second tank 120a, respectively 120b, for example between the hydrogen utilization unit 130 and the second tank 120a, respectively 120b. The output 1201 a, respectively 1201 b, comprises for example one or more pipes and / or one or more walls.

The inlet 1203a, respectively 1203b, is for example provided with inlet locking means 1204a, respectively 1204b, which comprise for example a valve, for example a solenoid valve, are for example movable at least between an open position and a closed position . In the open position, the inlet 1203a, respectively 1203b, allows the flow of hydrogen to the second tank 120a, respectively 120b, for example from the first tank 1 10. In the closed position, the inlet 1203a, respectively 1203b , does not allow the flow of hydrogen from the second tank 120a, respectively 120b, for example from the first tank 1 10. The inlet 1203a, respectively 1203b, comprises for example one or more pipes and / or one or more walls .

The system 100 comprises, for example, the inlet 1301 of hydrogen of the hydrogen utilization unit 130 from the first tank 1 10 and / or the second tank 120a and / or the second tank 120b. The first input 1301 is for example provided with input blocking means 1302.

The outlet 101 may be provided with a non-return valve 1 104, for example to prevent any return of hydrogen from the outlet 1201a and / or the outlet 1201b and / or the inlet 1301 and / or the second reservoir 120 and / or the hydrogen utilization unit 130.

tanks The first tank 1 10 comprises for example a first chamber 1 12, the first material January 1 being for example disposed within the first chamber 1 12.

The second reservoir 120 comprises, for example, a second enclosure 122, the second material 121 being for example disposed within the second enclosure 122. The second enclosure 122 has, for example, a higher pressure resistance than the first enclosure 1 12.

Alternatively or in addition, the first reservoir 1 10 and the second reservoir (s) 120 or 120a and 120b comprise a common enclosure in which are disposed the first material 1 1 1 and the second material 121. The common enclosure is for example merged with the first enclosure 1 12 and / or the second enclosure 122. Alternatively, the first enclosure 1 1 2 and / or the second enclosure 122 is disposed within the common enclosure.

hydride

General description

The first material 1 1 1 and / or the second material 121 comprises or is a hydrogen storage material, for example adapted to form a hydride, for example a metal hydride.

The first material 1 1 1 and / or the second material 121 comprises or is for example a metal alloy adapted to form a hydride, for example at room temperature.

The first material 1 1 1 and / or the second material 121 comprises for example a powder.

The first material 1 1 1 and / or the second material 121 may comprise or consist of a metal alloy, for example an intermetallic compound of type A _n B _m , where A and B are elements metallic chemicals, and n and m of natural numbers greater than or equal to 1, for example of type AB _m , for example AB2 or AB5, for example of type A _n B, for example A2B, for example AB.

The first material 1 1 1 and / or the second material 121 may comprise or consist of a metal alloy, for example an intermetallic compound, comprising iron and / or vanadium and / or titanium and / or zirconium and / or or magnesium. The first material 1 1 1 and / or the second material 121 may comprise or consist of at least one alloy of the LaNis and / or FeTi and / or TiCr and / or TiV and / or TiZr and / or TiMn2 type and / or Mg, and / or the corresponding hydride (s). The first material 1 1 1 and / or the second material 121 may also comprise or consist of at least one hydride of NaAIH ₄ and / or L 1 NH 2 and / or LiBH ₄ and / or Mgh type, the form (s) corresponding dehydrogen (s). The first material 1 1 1 and / or the second material 121 may comprise or consist of an alloy of the type Ti (i-y) Zr _y (MnVFe) 2 with y greater than or equal to 0 and y less than or equal to 1 . In particular, the first material 1 1 1 and the second material 121 may comprise or consist of such an alloy, the first material 1 1 1 having a zirconium mass fraction strictly greater than that of the second material 121. For example, the base of the alloy of the first material 1 1 1 differs from the base of the alloy of the second material 121. For example, the base of the alloy of the first material 1 1 1 and the base of the alloy of the second material 121 are identical, the first material 1 1 1 and the second material 121 differing by at least one alloying element.

Detailed examples

With reference to FIG. 5 are described the hydrogen pressure composition isotherms in bar as a function of the hydrogen content expressed as a mass percentage of hydrogen of a Ti (i-y) Zr _y (MnVFe) 2 type alloy with y greater than or equal to 0 and y less than or equal to 1, example with a weight percent Zr- of about 6%, i.e. with y = 0.1, for example used as the first material. The first reservoir is, for example, initially charged at 50 ° C. at an absolute pressure of 21 bar, which corresponds to a hydrogen content of approximately 1.5% stored in the alloy. When the temperature increases the new pressure obtained is defined by the desorption curve, whereas when the temperature decreases the new pressure obtained is defined by the corresponding absorption curve. Thus, for a temperature rise to a critical temperature of 80 ° C, a critical pressure of 48 bar can be obtained.

The critical pressure corresponds to a predefined value and determined as critical for the device.

The critical pressure is for example predetermined for a given critical temperature and for a given quantity of hydrogen stored, that is to say that for this quantity of hydrogen stored in the tank, at the critical temperature, the pressure is less than or equal to the critical pressure, for example strictly less than the critical pressure.

Since the hydrogen must be released from the hydride in order to increase the pressure in the atmosphere, a slightly lower pressure will be formed depending on the free volume in the first chamber to be filled with hydrogen. At 20 ° C, an absolute storage pressure slightly above 9 bar (depending on the free volume) is formed. Pressure change is also important for discharging the hydride. The first reservoir can, for example at best, provide hydrogen until an equilibrium pressure for desorption is equal to an inlet pressure of one use unit. However, to obtain a substantial hydrogen flow from the first reservoir, a certain pressure difference between the equilibrium pressure and the actual pressure is required. For example, the operation of the first tank at 1, 2 kg of this alloy at temperatures below 10 ° C results in a pressure difference too low to have a sufficient flow to feed a hydrogen utilization unit 130, such as a fuel cell, of 1 kW until the heat rejection heat of the use unit is used to heat the first tank. A minimum operating temperature is therefore necessary, this temperature can be reduced by modulating the power of the utilization unit 130 in order to require a smaller pressure difference.

With reference to FIG. 6 are described the hydrogen pressure composition isotherms in bar as a function of the hydrogen content expressed as a mass percentage of hydrogen of various Ti (iy) Zry (MnVFe) 2 type alloys with y greater than or equal to at 0 and y less than or equal to 1, for example with mass percentages in Zr of about 3% and 6%, that is to say respectively y = 0.05 and 0.1, the lowest being by example used as the second material, and the highest being for example used as the first material, for example arranged as illustrated in FIG. 1, for example as implemented in FIG. 3. The first reservoir contains for example 1, 2 kg of first material and the second reservoir contains for example 200 g of second material. At temperatures of about 10 ° C and lower, the equilibrium pressure of the second material is sufficiently high to feed the use unit 130, such as a fuel cell, of 1 kW. The hydrogen utilization unit then produces heat rejects used to heat the first material up to 50 ° C. During start-up, the outlet blocking means 1 102 of the first tank and / or the inlet blocking means of the second tank are in the closed position so as to block any fluid communication with the second tank 120 or the unit use 130, for example with the rest of the system, and the input and / or output blocking means 1202 and 1302 are in the open position. Once the temperature is reached, the second tank 120 is recharged with hydrogen, for example as shown in FIG. 3. At lower temperatures and / or to facilitate the desorption of the second tank 120, it is it is possible to use the second heating means 123 to raise the temperature of the second material. Since the mass of the second material is substantially smaller compared to the rest of the system and / or in particular the first material, and can operate at lower temperatures, the heating of the second material is much more efficient than the heating of the first material. material for supplying the use unit 130.

With reference to FIG. 7 are described the hydrogen pressure isotherms in bar as a function of the hydrogen content expressed in mass percentage of hydrogen (PCT), for two different alloys of Ti (i _-y ) Zry (lvlnVFe) 2 type. with y greater than or equal to 0 and y less than or equal to 1, for example with mass percentages in Zr- of approximately 3% and 6%, that is to say y = 0.05 and 0.1 respectively. , the weakest being for example used as the second material, and the highest being for example used as the first material, for example arranged as illustrated in FIG. 1, for example as implemented in FIG. in hydrogen of the second tank 120 by the first tank 1 10 is here presented. Once the first material has reached its operating temperature, for example about 50.degree. C., it is used to recharge the second material, for example by positioning the output blocking means 1 102 in the open position, and possibly the means for inlet and / or outlet blocking 1202 and 1302 in the open position, so as to allow a fluid connection between the first tank 1 10 and the second tank 120. The first material and the second material are then subjected to the same defined pressure by the desorption curve of the high Zr content alloy of the first tank 1 10. In order to better recharge the second tank 120, about 0.25 of the mass percentage of the first tank 1 10 are necessary. In order to recharge the second tank 120 at 10 ° C an absolute minimum pressure of 1 1 bar is required. Once the second tank 120 is sufficiently recharged, the input and / or output blocking means 1202 are placed in the closed position in order to block the fluid communication between the first tank 1 10 and the second tank 120, the means 1 102 and 1302 being for example in position opened. The level of hydrogen refilling sufficient can be determined either by direct measurement of the amount of hydrogen in the second tank 120, or by monitoring the pressure until it falls below a certain threshold, for example 1 1 bar .

In particular, the first material 1 1 1 and the second material 121 may comprise or consist of such an alloy, the first material 1 1 1 having a zirconium mass fraction of between 5% and 15%, for example between 5% and 12%, for example substantially equal to 6%, and / or the second material 121 having a zirconium mass fraction of between 1% and 5%, for example between 2% and 4%, for example substantially equal to 3%. The use of such a first material with a high zirconium mass fraction makes it possible to reduce the costs associated with the choice and / or the production of the material. The use of such mass fractions is particularly suitable for applications related to fuel cells for a vehicle.

The first material 1 1 1 and / or the second material 121 may comprise or consist of a material adapted to form a hydride of NaAIH type ₄ of the LiNh type.

sizing

The system is for example configured to check an inequality of the type:

Pl, of (T1, op) - P2, ab (T ₂ , max) C) where pi.de is the desorption equilibrium pressure of the first reservoir, Ti, ₀ p is at least an operating temperature of the first reservoir , for example an operating temperature when the heat is supplied by the steady-state hydrogen utilization unit, p2, ab is the ad / absorption equilibrium pressure of the second reservoir, T2, max is at least one charging temperature of the second tank, for example the maximum charging temperature of the second tank.

Thus, the desorption equilibrium pressure of the first reservoir 1 10, for example at at least one operating temperature of the first reservoir 1 10, for example a nominal operating temperature, is for example greater than the equilibrium pressure of ad / absorption of the second tank 120, for example at least one refilling temperature of the second tank 120, for example at the operating temperature of the first tank, for example at the maximum charging temperature of the second tank. It is thus possible to recharge the second tank 120 with the aid of the first tank 1 10.

The system remains effective, low losses of efficiencies that can possibly be felt only for very low temperatures.

It is thus possible to dimension separately the first tank and the second tank, resulting in cost advantages.

The system is for example configured to check an inequality of the type:

Pl, of (T2, max) - V input (^) where pi.de is the desorption equilibrium pressure of the first reservoir, T2, max is at least one reloading temperature of the second reservoir, for example the maximum temperature of reloading the second reservoir, and p _en try is an input pressure of the utilization unit, for example a minimum pressure at which a flow of hydrogen from the first tank may enter the unit of use.

The verification of equations (1) and (2) ensures a compromise between the maximum and / or critical pressure of the first reservoir when it is full and the maximum or critical temperature of reloading the second tank.

By maximum pressure of the device or a reservoir is meant, for example, a pressure at which the device or the reservoir is not damaged when it is placed in operation. The maximum pressure of the device or of the reservoir is, for example, less than or equal to 300 bars, for example equal to 300 bars, for example less than or equal to 100 bars, for example equal to 100 bars, for example greater than or equal to 20 bars, for example equal to 20 bars.

By maximum temperature of the device or a tank, for example means a temperature at which the device or the tank is not damaged when it is placed in operation. The maximum temperature of the device or the reservoir is, for example, less than or equal to 150 ° C., for example less than or equal to 100 ° C., for example greater than or equal to 80 ° C.

Heating means

The system 100 comprises for example first heating means 1 13 of the first material 1 1 1 dedicated, for example a heater, for example a resistor, for example a heat exchanger. It is thus possible, if the temperature of the first tank does not allow its immediate use, at least not with sufficient efficiency, to heat the first tank while the second tank provides the necessary hydrogen, then to use the first tank as main or sole source of hydrogen for the unit of use of hydrogen and / or to recharge the second tank.

The first heating means 1 13 are for example adapted to receive all or part of the energy or heat necessary for their operation of the hydrogen utilization unit 130. The heat is for example directly supplied by means of a heat exchanger from the unit for using hydrogen 130 to the first tank 1 10. The heat comprises or consists, for example, of the heat resulting from the reduction taking place in the hydrogen utilization unit 130 when this This is a fuel cell. The heat comprises or consists of, for example, heat, for example heat from the gas exhaust line and / or from a heat engine, for example a hydrogen engine. The heat comprises or consists of, for example, heat resulting from a selective catalytic reduction reaction and / or the operation of an engine, for example a hydrogen engine. Alternatively or in addition to the energy is for example the electrical energy produced by the hydrogen utilization unit 130, the heating means 1 13 comprising at least one resistance.

In particular, the system can be configured so that, at a given environment temperature, the second reservoir can provide hydrogen in sufficient quantity and / or flow and / or duration, to the unit of using hydrogen 130 to allow heating of the first tank 1 10 by the first heating means 1 13, in particular from an environmental temperature, in particular up to an operating temperature allowing the desorption of hydrogen from the first tank 1 10, in particular so as to allow the operation of the hydrogen utilization unit 130 without supply of hydrogen by the second tank 120. The system can in particular be configured so that, at a given environmental temperature, the second reservoir makes it possible to supply hydrogen in an amount of at least 20%, for example at least 40%, for example at least 100%, for example less than 300%, such energy and / or power and / or throughput. It is thus possible to provide a sufficient margin for several successive uses.

The operating temperature of the first chamber is for example a temperature at which the desorption equilibrium pressure of the first tank 1 10 is greater than the inlet pressure of the unit using hydrogen 130. The inlet pressure of the hydrogen utilization unit 130 is for example less than or equal to 10 bar, for example less than or equal to 6 bar, for example less than or equal to 5 bar . The operating temperature of the first chamber is, for example, greater than or equal to a maximum charging temperature of the second tank 120. The nominal operating temperature is, for example, between 20 ° C. and 80 ° C., for example between 30 ° C. and 70 ° C, for example about 50 ° C. The starting temperature is for example between -40 ° C and 0 ° C, for example between -30 ° C and -10 ° C, for example about -20 ° C.

The system 100 may for example comprise second heating means 123 of the second material 121 dedicated, for example a heater, for example a resistor, for example a heat exchanger. It is thus possible to provide even more rapidly a large amount of hydrogen, for example so as to boost the operation of the hydrogen utilization unit 130.

Cooling means The system 100 comprises, for example, first cooling means 1 15 of the first material 1 1 1 dedicated. The first heating means 1 13 form for example the first cooling means 1 15. The cooling is for example carried out by circulating a cooling fluid, for example air and / or Peltier effect.

The system 100 comprises for example second cooling means 125 of the second material 121 dedicated. The second heating means 123 form for example the second cooling means 125. The cooling is for example carried out by circulating a cooling fluid, for example air and / or Peltier effect. Storage capacity

The second tank 120 has for example a hydrogen storage capacity lower than that of the first tank 1 10. The second tank 120 has for example a hydrogen storage capacity less than or equal to 50%, for example less than or equal to 30% for example less than or equal to 20% of that of the first tank 1 10. The second tank 120 has for example a hydrogen storage capacity greater than or equal to 10% of that of the first tank 1 10.

The second tank 120 has for example a smaller volume than the first tank 1 10. The second material 121 has for example a smaller volume than the first material 1 1 1. Indeed, the second tank serving only for limited periods, its capacity, and therefore its size, can be limited. It also makes it possible to dimension it effectively by limiting the risks that it can present in terms of security. Thus, it is not necessary to resort to the use of a valve that involves a loss of hydrogen, or in any case it is possible to limit the use of this valve to specific cases. Moreover, it is thus possible to limit the energy losses with respect to an electric battery which would involve significant losses as time passes, and during temperature changes.

Working conditions

The second material 121 is for example adapted to supply hydrogen, for example according to a request from the unit of use, for example from control means as described below, at a temperature T _m in lower or equal to 0 ° C, for example less than or equal to -10 ° C, for example less than or equal to -20 ° C, for example at a pressure of between 1 and 15 bar, for example between 1 and 10 bar for a fuel cell, for example between 5 and 15 bar for an internal combustion engine or heat engine, for example between 1 and 2 bar for a gas treatment application, for example at ambient pressure, for example of the order of 1 bar, for example to allow the operation of the use unit 130.

The first tank 1 10 has for example a nominal operating temperature between 25 ° C and 150 ° C, for example between 30 ° C and 120 ° C, for example between 40 ° C and 100 ° C.

The first tank 1 10, for example the first chamber 1 12, is for example adapted to withstand an internal pressure having a value between 25 and 100 bar, for example between 40 and 60 bar, for example between 45 and 55 bar, the pressure being a relative and / or absolute pressure.

The first tank 1 10, for example the first chamber 1 12, is for example adapted to withstand a temperature having a value between 40 ° C and 150 ° C, for example between 50 ° C and 90 ° C, for example between 60 ° C and 85 ° C, for example about 80 ° C.

The system 100 is for example adapted so that the first tank 1 10 and / or the first chamber 1 12 is subjected only to temperatures less than or equal to 120 ° C, for example less than or equal to 100 ° C, for example less than or equal to 80 ° C. The system 100 is for example adapted so that the first tank 1 10 and / or the first chamber 1 12 is subjected only to pressures less than or equal to 80 bars, for example less than or equal to 60 bars, for example lower or equal to 50 bars.

The second tank 120 has for example a mass strictly smaller than that of the first tank 1 10. The second material 121 has for example a mass strictly lower than that of the first material 1 1 1. The level of filling of the second material 121 in the second chamber 122 is for example greater than or equal to 5%, for example 25%, for example 50% of the volume of the second chamber 122.

The second tank 120 has for example an operating temperature, for example of nominal operation, less than or equal to 10 ° C, for example less than or equal to 15 ° C, for example less than or equal to 20 ° C.

The second tank 120, for example the second chamber 122, is for example adapted to withstand an internal pressure having a value of between 20 and 130 bar, for example between 50 and 110 bar, for example between 70 and 90 bar, example of about 80 bar, the pressure being a relative pressure and / or absolute.

The second tank 120, for example the second chamber 122, is for example adapted to withstand a temperature having a value of between 40 ° C. and 120 ° C., for example between 50 ° C. and 90 ° C., for example between 60 ° C. C and 85 ° C.

Filtration means

The first tank 1 10 and / or the second tank 120 may comprise incoming and / or outgoing gas particle filtration means, for example one or more filter elements comprising one or more filters. The filter element is for example adapted to allow the passage of hydrogen gas and / or to prevent the passage of particles of the first material or the second material. The filter element is for example adapted to prevent the passage of material in the solid state, for example the first material and / or the second material. The filter element may comprise a porous material, for example one or more porous section pipe (s), and / or a nonwoven fabric or nonwoven fabric. fibers, and / or a corrugated sheet, for example a corrugated sheet, and / or one or more foam (s) and / or one or more wired structure (s).

Heat transfers

The first tank 1 10 and / or second tank 120 has for example an internal architecture for rapid heat transfer.

Means of command

The system may comprise control means 170. The control means may comprise at least one processor and / or a random access memory and / or a read-only memory and / or display means, for example a terminal.

The control means 170 may comprise one or more sensors adapted to measure and provide one or more measurements of the system state, for example in real time. The control means 170 may comprise a first temperature sensor 1 14 of the first reservoir, and / or a second temperature sensor 124 of the second reservoir, and / or a third temperature sensor 134 of the hydrogen utilization unit. . The control means 170 may comprise a first pressure sensor 1 14 of the first reservoir, and / or a second pressure sensor 124 of the second reservoir, and / or a third pressure sensor 134 of the hydrogen utilization unit. . The control means 170 may comprise a first hydrogen concentration sensor 1 14 of the first tank, and / or a second hydrogen concentration sensor 124 of the second tank.

The control means 170 may for example control the first tank 1 10, for example the first heating means 1 13. The control means 170 may for example control the second tank 120, for example the second heating means 123. The control means 170 may for example control the hydrogen utilization unit 130. The control means 170 may, for example, control the output 1 101, for example the first locking means 1 102. The control means 170 may for example control the output 1201, for example the second blocking means 1202. The control means 170 may for example control the input 1301, for example the third locking means 1302.

The control means are for example configured to implement a method as described below.

The control means are, for example, configured so as not to use the hydrogen of the second tank 120 for starting the system if the temperature of the first tank 1 10 is greater than a threshold temperature, which is, for example, greater than or equal to -5 ° C. C, for example less than or equal to 15 ° C, for example substantially equal to 10 ° C.

Fuel cell

With reference to FIGS. 1 and 2, there is described the system 100 in which the hydrogen utilization unit 130 comprises or is a fuel cell. The system 100 is thus a system for storing and supplying hydrogen to a fuel cell, for example for a device, for example for a vehicle or a stationary device. There is also disclosed a fuel cell system including system 100.

The fuel cell is for example a fuel cell membrane proton exchange. The fuel cell is for example adapted to provide at output a nominal electric power sufficient for a given application.

Exhaust line The hydrogen utilization unit 130 may comprise or be an exhaust line or an exhaust gas treatment device by selective catalytic reduction. The system 100 is thus a system for storing and supplying hydrogen to an exhaust line and / or a catalyst for a device, for example for a vehicle or a stationary device. There is also described a system for treating the exhaust gases of a device, for example a vehicle or a stationary device, comprising the system 100.

Thermal motor

The hydrogen utilization unit 130 may comprise or be a heat engine. It is thus possible to supply the heat engine directly with hydrogen. The system 100 is thus a system for storing and supplying hydrogen to a heat engine, for example for a vehicle or a stationary device. There is also described a system for supplying energy by a heat engine, for example a vehicle or a stationary device, comprising the system 100.

Process

With reference to FIGS. 3 and 4, there is described a method of supplying hydrogen to a hydrogen consumption unit, for example such as that described above. The method is for example adapted to be implemented by the system 100 described above or implemented by the system 100 described above.

The method is or includes, for example, a method of starting the system and / or a method of using the system, for example during operation. The method comprises for example a step of receiving a hydrogen demand for the utilization unit 130, and / or of calculating a hydrogen demand for the utilization unit 130, by the control means 170. The steps described below are for example implemented on command of the control means 170 and / or depending on the hydrogen demand. The hydrogen demand is for example updated, for example at regular intervals, for example in real time.

The method comprises, for example, a step 800 of increasing the temperature of the first material January 1, for example until reaching the operating temperature.

The method comprises for example a step 802, for example carried out before and / or during step 800 and / or before and / or during a rise in temperature of the first material 1 1 1. Step 802 includes, for example, supplying the second tank 120 with the second stream of hydrogen to the use unit instead of the first stream. The rise in temperature is for example carried out by the first heating means 1 13. The first heating means 1 13 receive for example all or part of the energy or heat necessary for their operation of the utilization unit 130 , the heat being for example partially or completely resulting from the thermal discharges of the use unit 130.

The method may thus comprise, for example at the same time as step 800 and / or 802, the absence of supply of the first stream and / or blocking by the first blocking means 1 102 of the outlet 1 101.

The method may comprise, for example once the nominal operating temperature reached by the first material, a step 804 for supplying the first tank 1 10 of the first hydrogen stream to the unit of use 130. The method may comprise a step 806 for stopping the supply of the second stream to the utilization unit 130, for example carried out at the same time or after the step 804 has begun. It is thus possible to start or operate the system while the first tank is not yet in a state to meet the hydrogen demand necessary for the operation of the unit of use, for example when starting the system. .

The method may comprise a step 804 for supplying the first reservoir 1 10 of the first hydrogen stream to the utilization unit 130. The method may comprise a step 808 for supplying the second reservoir of the second hydrogen stream with the use unit in addition to the first stream. Step 808 is for example implemented in case of too strong demand for the first tank 1 10, that is to say for example a demand that the first tank can not satisfy in terms of flow. It is thus possible to simultaneously combine the two streams to meet a particularly important demand and / or abrupt hydrogen. Steps 804 and 808 are for example implemented as a result of one or more of the steps previously described. Step 808 is for example followed by a step of stopping the second flow and / or cooling the second reservoir 120.

The method may further comprise a step 810 for recharging the second reservoir with hydrogen by the first reservoir. It is thus possible to recharge in hydrogen the second tank which has already been used in a previous step.

Step 810 takes place, for example, at the same time as a step of supplying the first reservoir 1 10 of the first stream of hydrogen to the utilization unit 130. It is thus possible to maintain the normal operation of the unit of use 130 while preparing the possibility of new specific commands requiring the use of the second tank 120.

Step 810, for example, takes place at the same time as a step of supplying another second reservoir of the plurality of second reservoirs of the second hydrogen flow to the utilization unit 130. use of the first tank at reloading or parallel processing a specific request of the use unit 130 which requires the use of one of the second tanks 120.

Step 810, for example, takes place simultaneously with an absence and / or a reduction of supply by the first tank 1 10 of the first hydrogen stream to the unit of use 130, for example in the absence of a command to use the utilization unit 130 and / or in the absence of use of the utilization unit 130. It is thus possible to prepare the possibility of new specific commands requiring the use of the second tank 120 when the unit of use no longer requires hydrogen input.

At the end of at least one step of supplying the second reservoir of the second hydrogen stream, the second reservoir may have a sufficient charge to implement a new step of supplying the second hydrogen stream. It is thus possible to use the second tank 120 several times in succession, even if the tank has not been recharged or only partially recharged in the meantime. The loading is for example greater than or equal to 50%, for example greater than or equal to 30%, of the maximum loading of the second tank 120 considered for example at a given temperature, for example at room temperature.

The method may comprise a step of stopping the supply of hydrogen, for example by the first tank 1 10, for example to the utilization unit 130, the stopping stage comprising, for example, step 810. II It is thus possible to take advantage of an inevitable production of hydrogen by the first tank at the end of the supply stage.

The method may include a step of stopping the usage unit 130, the stopping step including for example step 810.

The method may include a system shutdown step, the shutdown step comprising for example step 810. It is thus possible to implement a shutdown step of the system, for example by preparing the possibility of new specific commands requiring the use of the second tank 120, for example during a next start.

An example of the behavior of such a system at start-up is for example illustrated in FIG. 3, which shows, in the upper part, as a function of time, the temperature in degrees Celsius within the first tank 31 (solid line) and that in the second tank 32 (in broken lines), and in the lower part, as a function of time, the hydrogen loading in percentage (charge rate) of the first tank 33 (solid line) and that of the second tank 34 ( in broken line). Different operating phases are separated by dashed lines. In a first phase corresponding to steps 800 and 802, the temperature of the first reservoir can increase without the latter being biased to supply hydrogen, the demand being entirely provided by the second reservoir. In a second phase corresponding to step 810, the first tank feeds the use unit and recharges the second tank, the latter thus seeing its temperature increase. In a third phase corresponding to steps 804 and 806, the first tank serves only to supply the utilization unit, the second tank recharged at 90% being at a standstill.

Another example of the behavior of such a system in use is for example illustrated in FIG. 4, which is represented, in the upper part, as a function of time, the temperature in degrees Celsius within the first tank 41 (in solid line) and that within the second reservoir 42 (in broken lines), and in the lower part, as a function of time, the hydrogen loading in percentage (charge rate) of the first reservoir 43 (solid line) and that of the second tank 44 (in broken lines). Different operating phases are separated by dashed lines. In a first phase corresponding to steps 804 and 806, the first tank serves only to supply the utilization unit, the second tank loaded at 90% being stopped. In second phase corresponding to steps 804 and 808, the utilization unit is fed by the first flow completed by the second flow. This is a response to a sudden and / or significant demand for hydrogen. In a third phase corresponding to step 810, the first tank supplies the utilization unit and recharges the second tank, the latter thus seeing its temperature increase. In a fourth phase corresponding to steps 804 and 806, the first tank serves only to supply the utilization unit, the second tank refilled at 90% being stopped.

Detailed example of a system including a fuel cell

According to an exemplary embodiment, the system 100 is intended for a motor vehicle and comprises the fuel cell with a power of about 1 kW and can thus produce about 1 kW of heat rejection heat flow at a rate of temperature of the order of 60 ° C. The system is for example as shown in Figure 1.

The first material 1 1 1 and the second material 121 are for example formed of an alloy of Ti (i _-y) _y Zr (MnVFe) 2, wherein y is greater than or equal to 0 and y is less than or equal to 1 , the first material 1 1 1 having a zirconium mass fraction substantially equal to 6%, ie y = 0.1, and that of the second material 121 being substantially equal to 3%, that is to say y = 0.05.

The second material 121 is for example adapted to supply hydrogen at a temperature T _m in greater than or equal to -20 ° C, for example at ambient pressure.

The nominal operating temperature for the first material is for example of the order of 50 ° C.

The second heating means 123 may, for example, emit and / or transmit to the second material 121 a power of at least 100 W, for example at least 160 W, for example at least 200 W, for example less than 300 W, for example about 250 W. The second heating means 123 may for example be powered by a battery, lithium-iron-phosphate type, having a capacity of 10 Wh at -20 ° C.

The second enclosure 122 has for example an outer diameter of about 46 mm. The second enclosure 122 has for example a height of about 60 mm.

The first tank 1 10 has for example a mass substantially equal to 2 kg. The first material 1 1 1 has for example a mass substantially equal to 1, 2 kg. The first material 1 1 1 is for example adapted to store substantially 18 g of hydrogen. The first tank 1 10 is for example sized to operate the fuel cell for example about 18 minutes.

The first tank 1 10, for example the first chamber 1 12, is for example adapted to withstand an internal pressure having a value between 45 and 55 bar, the pressure being a relative pressure and / or absolute.

The first tank 1 10, for example the first chamber 1 12, is for example adapted to withstand a temperature of about 80 ° C.

The system 100 is for example adapted so that the first tank 1 10 and / or the first chamber 1 12 is only subjected to temperatures lower than or equal to 80 ° C and at pressures less than or equal to 50 bars.

The second tank 1 20 has for example a mass substantially equal to 0.5 kg. The second material 121 has for example a mass substantially equal to 0, 15 kg. The second material 121 is for example suitable for storing about 3 g of hydrogen. The second tank 120 is for example sized to operate the fuel cell for example about 3 minutes. The second reservoir 120 is, for example, sized to operate the fuel cell so as to produce, for example, about 50 Wh (180 kJ) of dissipated heat. At cold start, the second tank 120 provides hydrogen during the first minutes until the first tank 1 10 is sufficiently heated. The second tank 120 is then recharged with hydrogen from the first tank 1 10 so that it can be used for example at the next start.

To heat the first tank, which has a heat capacity of about 0.5 J / (gK), from -20 ° C to 50 ° C, about 70 kJ are required, ie about 40% of the capacity of the second tank 120, including sufficient margin to cover losses and heating of other components.

The second tank 120 has for example a hydrogen storage capacity substantially equal to 17% of the hydrogen storage capacity of the first tank 1 10.

The second tank has for example a maximum operating temperature for recharging less than or equal to 10 ° C.

The second tank 120, for example the second chamber 122, is for example adapted to withstand an internal pressure having a value of about 80 bar, the pressure being a relative and / or absolute pressure.

The second tank 120, for example the second chamber 122, is for example adapted to withstand a temperature having a value between 60 ° C and 85 ° C.

In the case where a plurality of first tanks 1 10 are used successively, it is particularly easy to combine the heating of one or more first tanks 1 10 and additional heating aid provided by the second tank 120.

Detailed example of a system including a heat engine According to an exemplary embodiment, the system 100 is intended for a motor vehicle and comprises a heat engine. The heat engine has for example a power of about 3 kW.

The first material 1 1 1 is for example formed of an MgNi type alloy. The first tank 1 10 is for example exchangeable.

The second material 121 is for example formed of an alloy of Ti (iy) Zry (MnVFe) 2 type, where y is greater than or equal to 0 and y is less than or equal to 1, the second material 121 having a mass fraction of zirconium substantially equal to 3%, that is to say y = 0.05.

The first tank 1 10 has for example a mass substantially equal to 4.5 kg. The first material 1 1 1 has for example a mass substantially equal to 1, 5 kg. The first material 1 1 1 is for example adapted to store substantially 82 g of hydrogen.

Considering an efficiency of 25% the heat engine can run for about 14 minutes at full power on a single first tank 1 10 and thus produce about 9000 W heat rejection heat flow at a temperature of about 600 ° C in the exhaust gas flow. The first material 1 1 1 is previously loaded at a temperature above 300 ° C at an absolute pressure of less than 20 bar to be fully charged.

The second tank 1 20 has for example a mass substantially equal to 2.5 kg. The second material 121 is for example suitable for storing about 25 g of hydrogen, ie about 30% of the storage capacity of the first material 1 1 1.

The heat engine can run for about 4 minutes at full power on the basis of the second tank 120 for a total of 2300 kJ heat rejection heat.

To heat the first tank 1 10, which has a heat capacity of about 0.5 J / (gK), from -20 ° C to 400 ° C, about 950 kJ are required, ie about 40% of the capacity of the second tank 120, including a sufficient margin to cover losses and heating of other components.

The second tank 120, for example the second chamber 122, is for example adapted to withstand a temperature of the order of 50 ° C.

At startup, the second tank 120 provides hydrogen during the first minutes until the first tank 1 10 is sufficiently heated. The second tank 120 is then recharged with hydrogen from the first tank 1 10 so that it can be used for example at the next start.

Claims

1. A system for storing and supplying hydrogen to a hydrogen utilization unit (130), comprising:

a first hydrogen storage tank (1 10) comprising a first material (1 1 1) for the storage of hydrogen by sorption,

a second hydrogen storage tank (120) comprising a second material (121) for the reversible storage of hydrogen by sorption,

a hydrogen outlet (101) from the first reservoir to the second reservoir and / or the hydrogen utilization unit,

a hydrogen outlet (1201) from the second reservoir to the hydrogen utilization unit,

The system of claim 1, wherein the system is configured to allow the first reservoir to provide the first flow to the second reservoir to recharge the second reservoir with hydrogen.

3. System according to any one of the preceding claims, wherein the first material (1 1 1) and / or the second material (121) is adapted to form a hydride, preferably a metal hydride.

4. System according to any one of the preceding claims, wherein the second reservoir (120) is for example configured to provide, at ambient temperature, the second hydrogen stream so as to allow the operation of the use unit. .

5. System according to any one of the preceding claims, wherein the hydrogen outlet of the first reservoir to the second reservoir and / or the hydrogen utilization unit is provided with a non-return valve.

The system of any of the preceding claims, wherein the hydrogen utilization unit comprises a fuel cell and / or an exhaust gas treatment system and / or a hydrogen engine.

7. System according to any one of the preceding claims, wherein the at least one second tank comprises a plurality of second tanks, preferably adapted to alternately supply the second stream.

8. System according to any one of the preceding claims, wherein for each second tank, the system comprises a hydrogen outlet of the second tank to the hydrogen utilization unit and a hydrogen inlet of the second tank. , the inlet being at least partially separate from the outlet.

9. System according to any one of the preceding claims, further comprising control means (170) configured to implement the method according to any one of claims 10 to 14.

A method of supplying hydrogen to a hydrogen consumption unit, the method being implemented by a system according to any one of the preceding claims.

1 1. Method according to the preceding claim, comprising steps of:

before and / or during the rise in temperature, supplying the second reservoir of the second stream of hydrogen to the utilization unit instead of the first flow,

- Once the operating temperature reached by the first material, providing the first reservoir of the first hydrogen stream, and preferably stopping the supply of the second stream.

The method of any one of claims 10 to 11, comprising steps of:

- Supply by the second reservoir of the second hydrogen stream to the use unit in addition to the first flow.

13. The method of any one of claims 10 to 12, further comprising a step of reloading the second tank with hydrogen by the first tank.

14. A method according to any one of claims 10 to 13, wherein, at the end of at least one step of supplying the second reservoir of the second hydrogen stream, the second reservoir has a sufficient loading to implement a new stage of supplying the second hydrogen stream.