FUEL CELL VEHICLE OR HYDROGEN INTERNAL COMBUSTION ENGINE INCLUDING AN ENERGY RECOVERY DEVICE

Abstract

The invention relates to a motor vehicle (1000) comprising a fuel cell (50) or a hydrogen engine (60), a high-pressure line connectable to an external hydrogen pump (200) for supplying at least one hydrogen tank (10), from the outlet of which a high-pressure pipe (11) supplies a turbine (20) coupled to an alternator (30), from the outlet of which turbine (20) a low-pressure line is arranged to supply the fuel cell (50) or the hydrogen engine (60), and comprising a device (100) for recovering the energy from the compression of the hydrogen, which includes the turbine (20) and an on-board thermal energy storage system (40) based on a phase-change material, between the high-pressure line and the low-pressure line. It further relates to a network comprising motor vehicles (1000) and hydrogen pumps (200), and an energy recovery method. Figure 1

Description

Title of the invention: VEHICLE WITH A FUEL CELL OR DIHYDROGEN INTERNAL COMBUSTION ENGINE COMPRISING AN ENERGY RECOVERY DEVICE

[0001] The invention relates to a motor vehicle comprising a fuel cell or a dihydrogen internal combustion engine, a high-pressure line connectable to an external dihydrogen pump, for supplying at least one dihydrogen tank at the outlet of which a high-pressure pipe supplies a turbine coupled to an alternator, at the outlet of which turbine a low-pressure line is arranged to supply the fuel cell or the dihydrogen engine.

[0002] The invention also relates to a network comprising such motor vehicles and such dihydrogen pumps.

[0003] The invention also relates to a method for recovering energy from a motor vehicle running on hydrogen.

[0004] The invention relates to the field of motor vehicles running on hydrogen, and the field of energy saving on hydrogen supply networks and on motor vehicles themselves.

[0005] The invention relates to the field of fuel cell electric vehicle (FCEV) or hydrogen internal combustion engine (H2ICE) motor vehicles.

[0006] FCEV or H2ICE type vehicles incorporate tanks that store dihydrogen (H2) at 700 bar, or 70 MPa. This pressure, initially 350 bar, was recently increased to 700 bar in order to increase the volumetric energy density, and thus increase the autonomy of FCEVs. This pressure of 700 bar is now becoming the international standard in this area.

[0007] Current H2 filling stations internally integrate H2 cooling before filling the vehicle tanks. Indeed, the internal temperature of the tank is limited to 85°C by the regulations: SAE (Society of Automotive Engineers) J2601. Fueling Protocols for Light Duty Gaseous Hydrogen Surface Vehicles; SAE International: Warrendale, PA, USA, 1999, and ISO / TS 15869.2009 (International Standard Organization) Gaseous Hydrogen and Hydrogen Blends Land Vehicle Fuel Tanks; Geneva, Switzerland, 2009.

[0008] Reaching this temperature threshold during H2 filling limits the mass of H2 stored in the tanks. Thus, the cooling of the H2 implemented in the station before filling the tank allows the increase in tank temperature to be contained within the limits set by these standards.

[0009] However, the increase in the filling pressure from 350 to 700 bar is accompanied by a very sharp rise in temperature of the H2 and the tank during rapid filling (i.e. lasting a few minutes, equivalent to that of filling up with petrol or diesel for a conventional vehicle with a spark-ignition or compression-ignition internal combustion engine), due to the compression of the H2.

[0010] The cooling implemented within the station before filling the tank is very energy-intensive and costly, and the associated thermal energy is lost, without being able to be used within the vehicle, for better integration of the H2 in the vehicle (adaptation of the temperature at the level of the H2 supply at the input of the fuel cell (FC, from the English "fuel cell") or the H2ICE).

[0011] Similarly, the compression energy of H2, and in particular the additional energy necessary for compression from 350 bar to 700 bar, is currently lost at the various H2 expansion stages between the tank and the FC supply (3 to 8 bar, up to 20-23 bar) or H2ICE (30 bar to 40 bar). Thus, the conversion efficiency of the energy consumed at the filling station (energy consumption for each kWh at the vehicle wheel) to compress H2 to 700 bar from the network to 60 bar, is only 65%. (source: Campanari, S.; Manzolini, G.; Iglesia, FG Energy analysis of electric vehicles using batteries or fuel cells through well-to-wheel driving cycle simulations. J. Power Sources 2009, 186, 464-477).

[0012] Document WO2023 / 052249 describes a hydrogen supply system for a vehicle fuel cell, comprising an evaporator equipped with a supply of dihydrogen in liquid form and an outlet for hydrogen in gaseous form, this evaporator comprising an enclosure inside which a porous material is arranged, the enclosure being crossed by a heat transfer fluid pipe.

[0013] In summary, the cooling of the H2 implemented within the station, prior to filling the tank under 700 bar, is very energy-intensive and expensive, and the associated thermal energy is lost. The compression energy of the H2 at 700 bar is currently lost at the level of the various H2 expansion stages between the tank and the supply of the FC fuel cell or the H2ICE dihydrogen internal combustion engine.

[0014] The objective of the present invention is to overcome these drawbacks by proposing the interposition of a turbine between the H2 tank and the fuel cell, this turbine using the expansion of the H2 to recover mechanical energy. This recovered mechanical energy is transformed into electrical energy by an alternator or a generator, and the thermal energy from the expansion of the H2 (low temperature and pressure) is stored in an energy storage system, to be used during the next filling of the tank to cool the H2 (high temperature and pressure) from the station before filling the tank.

[0015] To achieve this objective, the invention proposes a motor vehicle comprising at least one fuel cell or at least one dihydrogen internal combustion engine, arranged to consume dihydrogen, said motor vehicle comprising a high-pressure hydrogen line which comprises a supply pipe arranged to be connected to a dihydrogen pump external to said motor vehicle for supplying said motor vehicle with dihydrogen, said supply pipe being arranged to supply dihydrogen to a tank inlet pipe for supplying dihydrogen to at least one dihydrogen tank on board said motor vehicle and at the outlet of which at least one dihydrogen tank a high-pressure pipe supplies a turbine coupled to an alternator for energy recovery,and at the outlet of which turbine said motor vehicle comprises a low pressure hydrogen line which comprises a low pressure pipe arranged to supply, at the level of a service pipe, dihydrogen under temperature and pressure conditions required by said at least one fuel cell or by said at least one dihydrogen internal combustion engine which said motor vehicle comprises.

[0016] According to the invention, said motor vehicle comprises a device for recovering the energy from the compression of dihydrogen, which comprises, on the one hand, said turbine, and, on the other hand, an on-board thermal energy storage system based on phase-change material, between said high-pressure hydrogen line and said low-pressure hydrogen line.

[0017] Thanks to the invention, energy is recovered, not only at the alternator level, but also at the level of the device for recovering the energy from the compression of the dihydrogen, where the latent heat of change of state is used. The necessary cooling of the dihydrogen is at least partially carried out on board the vehicle itself.

[0018] Advantageously, said turbine is arranged to carry out an expansion of the dihydrogen which passes through it, from a high pressure Pdefhp in said high pressure pipe to a low pressure Pdeflp in said low pressure pipe, said expansion of the dihydrogen making it possible to lower its temperature from a high pressure temperature Tdefhp in said high pressure pipe to a low pressure temperature Tdeflp in said low pressure pipe, and said on-board thermal energy storage system is arranged to collect thermal energy coming from the dihydrogen downstream of said low pressure pipe, at a first input of said on-board thermal energy storage system by at least one said phase change material chosen so that its transition temperature Tpcm is higher than said low pressure temperature Tdeflp with a predetermined gap to allow a phase transition of each said phase change material.

[0019] Thus, the device for recovering the energy from the compression of dihydrogen carries out energy transfers both on the high-pressure hydrogen line and on the low-pressure hydrogen line, and the judicious choice of the phase-change material ensures the recovery of its latent heat of change of state.

[0020] Advantageously, the on-board thermal energy storage system comprises several stages of phase change materials, with different characteristics and different transition temperatures, so as to store thermal energy in said on-board thermal energy storage system by the successive use of the latent heats of the different phase change materials that said on-board thermal energy storage system comprises.

[0021] Thus, the effects of several phase change materials with different characteristics are combined, and energy recovery is optimized.

[0022] Advantageously, the device for recovering the energy from the compression of the dihydrogen comprises a discharge conduit for said turbine, arranged between said high-pressure pipe at the tank outlet and said first inlet of said on-board thermal energy storage system, said conduit being controlled by a turbine valve, so as to protect said turbine and regulate the mass flow rate of hydrogen passing through it.

[0023] This ensures protection of the turbine.

[0024] Advantageously, said device for recovering the energy from the compression of dihydrogen comprises, on said low-pressure hydrogen line, a first bypass conduit of said on-board thermal energy storage system which is arranged between said low-pressure pipe and said service pipe, and said first bypass conduit is controlled by a first valve, so as to regulate the mass flow rate of hydrogen passing through a low-pressure portion of said on-board thermal energy storage system.

[0025] This regulates the low pressure hydrogen line.

[0026] Advantageously, said device for recovering the energy from the compression of dihydrogen comprises, on said high-pressure hydrogen line, a second bypass conduit of said on-board thermal energy storage system which is arranged between a second inlet of said on-board thermal energy storage system downstream of said dihydrogen supply pipe, and a second outlet of said on-board thermal energy storage system upstream. of said tank inlet pipe, and said second bypass conduit is controlled by a second valve, so as to regulate the mass flow of hydrogen passing through a high pressure portion of said on-board thermal energy storage system.

[0027] This regulates the high pressure hydrogen line.

[0028] The invention also relates to a network comprising a plurality of such motor vehicles, and a plurality of such dihydrogen pumps.

[0029] According to the invention, each device for recovering the energy from the compression of the dihydrogen is arranged to communicate with each said dihydrogen pump, according to a bidirectional communication protocol arranged so that said vehicle controls the dihydrogen cooling system of said dihydrogen pump, and is arranged to lower the hydrogen consumption of said vehicle, and reduce or cancel the energy consumption for the cooling of the dihydrogen by said dihydrogen pump.

[0030] This saves a significant amount of cooling energy at the level of the dihydrogen pumps.

[0031] Advantageously, the only systems for cooling the dihydrogen of said automobile network are said devices for recovering the energy from the compression of the dihydrogen that are included in said motor vehicles of said automobile network.

[0032] It is then possible to completely do away with the presence of cooling systems at the level of the dihydrogen pumps.

[0033] The invention also relates to a method for recovering energy on a motor vehicle comprising at least one fuel cell or at least one dihydrogen internal combustion engine, arranged to consume dihydrogen.

[0034] According to the invention, said motor vehicle is equipped with a device for recovering the energy from the compression of dihydrogen, which device comprises, on the one hand, a turbine which is interposed between at least one dihydrogen tank on board said motor vehicle and a service pipe arranged to deliver dihydrogen under temperature and pressure conditions required by said at least one fuel cell or by said at least one dihydrogen internal combustion engine, and, on the other hand, an on-board thermal energy storage system based on at least one phase-change material, between a high-pressure hydrogen line comprising a supply pipe arranged to be connected to a dihydrogen pump external to said motor vehicle and to supply dihydrogen to said dihydrogen tank, and a low-pressure hydrogen line between said turbine and said service pipe,and in that each said at least one phase change material is chosen so that its transition temperature Tpcm is higher than the temperature Tdeflp of the dihydrogen at the outlet of said turbine with a difference which is calculated so that said phase change material undergoes a phase transition.

[0035]

[0036]

[0037]

[0038]

[0039] This allows you to transform an existing hydrogen-powered motor vehicle to improve its energy performance. Advantageously, said on-board thermal energy storage system is equipped with several stages of phase change materials, with different characteristics and different transition temperatures, so as to store in said on-board thermal energy storage system thermal energy accumulated by the successive use of the latent heats of the different phase change materials that said on-board thermal energy storage system comprises. This optimizes energy recovery. The invention will be further detailed by the description of non-limiting embodiments, and on the basis of the appended figures illustrating variants of the invention, in which: - [Fig.l] schematically illustrates the device for recovering the compression energy of H2, specific to the invention, integrated into a vehicle, and supplied by an H2 filling station; from upstream to downstream, this recovery device comprises a high pressure branch, part of which passes through an on-board thermal energy storage system, shown in a central position in the figure, and joins at least one H2 tank, which supplies a turbine coupled to an alternator, the recovery device comprises a low pressure branch, part of which, in particular supplied by the turbine, passes through the same on-board thermal energy storage system, which contains at least one phase change material, before the distribution of dihydrogen at the required temperature and pressure conditions to the user device, a fuel cell or a dihydrogen internal combustion engine; - [Fig.2] shows the evolution of temperatures within the on-board system of thermal energy storage, with length on the abscissa; - [Fig.3] is a diagram similar to [Fig.2], for an on-board thermal energy storage system comprising two stages of phase change materials; - [Fig.4] is a diagram similar to [Fig.3], for an embedded system of thermal energy storage comprising three stages of phase change materials; - [Fig.5] illustrates an automotive network comprising a plurality of such motor vehicles, and a plurality of such dihydrogen pumps. The invention relates to the recovery of energy in filling / supplying H2 of a vehicle 1000 comprising a fuel cell 50, or a combustion engine internal to dihydrogen 60.

[0040] Such a vehicle 1000 is arranged to be supplied with H2 by an H2 filling station 200, typically an H2 pump.

[0041] The invention relates to a device 100 and a method for recovering the compression energy of H2

[0042] The device 100 for recovering the compression energy of the H2 is implemented in the vehicle 1000 (of the electric type with fuel cell 50 FCEV, or with dihydrogen internal combustion engine 60 H2ICE) by the installation, on the H2 filling and distribution network: - a turbine 20 arranged on the H2 filling and distribution network, at the outlet of at least one H2 tank 10, and - an on-board thermal energy storage system 40 (TESS, from the English “thermal energy storage System”) based on phase change material (PCM, from the English “phase change material”), between the high and low pressure H2 lines: • high pressure: on the tank filling branch, between the H2 outlet 201 of the filling station 200 and the tank 10, and • low pressure: downstream of the tank 10, more particularly at the outlet of the turbine 20.

[0043] The turbine 20 replaces all or part of the conventional expanders, usually arranged at the outlet of the tank 10 and between the latter and the H2 supply 44 of the fuel cell 50 FC or the dihydrogen internal combustion engine 60 H2ICE. This turbine 20 is mechanically linked to an alternator 30, or to an electrical energy generator, so that the expansion of the H2 between the tank 10 and the supply of the fuel cell 50 FC or the dihydrogen internal combustion engine 60 H2ICE sets this turbine 20 in rotation which, by driving the alternator 30, generates electrical energy and thus significantly improves the efficiency of the vehicle 1000.

[0044] In addition, the thermal energy resulting from the expansion of the H2 (low temperature and pressure) is stored in the on-board thermal energy storage system 40 TESS to then be used during the next filling of the tank 10 to cool the H2 (high temperature and pressure) coming from the filling station 200 before filling the tank 10. To take full advantage of this, the cooling of the H2 by the filling station 200 is inhibited or greatly reduced, and thus the energy consumption by the filling station 200 is greatly reduced.

[0045] A bidirectional communication protocol must be implemented between the vehicle 1000 and the filling station 200, so that the vehicle 1000 controls the H2 cooling system of the filling station 200. The current state of the art for a FCEV fuel cell motor vehicle is a mono protocol directional with only communication of information from filling station 200 in H2 to vehicle 1000.

[0046] [Fig. 1] schematically shows the H2 circuit, consisting of the filling, from the H2 filling station 200 (which is located outside the perimeter of the vehicle 1000), of each H2 10 tank on board the vehicle and where the H2 is stored in the gaseous state under high pressure (700 bar), and the supply of H2 44 to the fuel cell 50 FC or the dihydrogen internal combustion engine 60 H2ICE (depending on the nature of the vehicle 1000) from the H2 10 tank.The present invention has on the H2 expansion branch, within the H2 filling and distribution network, between the H2 tank 10 and the H2 supply 44 of the 50 FC fuel cell or the 60 H2ICE dihydrogen internal combustion engine, a turbine 20, which recovers the thermodynamic work of expansion of the H2 from the H2 tank 10, and transforms it into mechanical torque which rotates an alternator or an electric generator 30 which converts the mechanical power of the turbine into electrical power, usable to meet the electrical consumption of auxiliaries, contribute to recharging an electrical storage device (e.g.: electrochemical motor storage device), or similar. Optionally, for the case of a 60 H2ICE dihydrogen internal combustion engine, the mechanical power of the turbine 20 can be introduced into the powertrain at the crankshaft output of the heat engine or at the gearbox input.To take full advantage of the H2 expansion, this turbine 20 replaces all or part of the conventional expanders usually arranged at the outlet of at least one tank 10 and between the latter and the H2 supply 44.

[0047] The invention also has, between on the one hand the high pressure H2 line, on the filling branch of the at least one H2 tank 10, between the H2 outlet of the H2 filling station 200 and the H2 tank 10, and on the other hand the low pressure H2 line, downstream of the H2 tank 10 and at the outlet of the turbine 20, an on-board thermal energy storage system 40 (TESS) based on phase change material (PCM), of dimension L.

[0048] During the running use of the vehicle, the pressure of the H2 from the H2 tank 10 is lowered to approximately 8 bar -14 bar using the turbine 20 (and no longer conventionally by pressure regulation means; and even to pressures lower than the level of the H2 supply 44), from a thermodynamic state of the H2 at the inlet of the turbine 20 characterized by the temperature Tdefhp (defueling high temperature), and the pressure Pdefhp (defueling high pressure), to a thermodynamic state of the H2 at the outlet of the turbine (therefore at the first inlet of the on-board thermal energy storage system 40 TESS) characterized by the temperature Tdefbp (defueling low pressure) and the pressure Pdefbp (defueling low pressure).

[0049] The use of the turbine 20 from the high pressure Pdefhp to the low pressure Pdeflp makes it possible to generate additional power, and the expansion of the H2 which takes place there lowers the temperature from the high temperature Tdefhp to the low temperature Tdflp, a temperature which can drop to temperature values ​​below -30°C, and down to -50°C or even -60°C.

[0050] At the end of the turbine 20, the H2 at the temperature Tdeflp passes through the on-board thermal energy storage system 40 TESS via a first inlet 22 and transfers its thermal energy there to a phase change material PCM chosen so that its transition temperature Tpcm is greater than Tdeflp (for example of the order of -25°C) and so that the phase change material PCM thus undergoes a phase transition and is therefore frozen.

[0051] [Fig.2] shows the evolution of temperatures within the on-board thermal energy storage system 40 TESS (the abscissa x = L and the dotted line indicate the length of the TESS: to the right of this line, we are then outside the TESS). This [Fig.2] shows that the H2, expanded at the outlet of the turbine 20, sees its temperature increase from Tdeflp to Tdefin (defueling temperature after the 1st outlet of the TESS, at the inlet / inlet in H2 44) while the phase change material PCM changes phase at the constant temperature Tpcm.

[0052] Thus, during the next filling with H2 of at least one H2 tank 10 from an H2 filling station 200, the thermal energy released by the low pressure H2, expanded from the turbine 20, and stored in the phase change material PCM of the on-board thermal energy storage system 40 TESS, will be used to cool the high pressure H2 coming from the H2 filling station 200 and passing through the on-board thermal energy storage system 40 TESS from a second inlet 202, from a high temperature Tfh (high fueling temperature: from 20°C to 40°C) to a lower temperature Tfc (cold fueling temperature: of the order of -20°C, according to the SAE J2601 - type A standard), before the actual filling with H2 of the H2 tank(s) 10. Thus, the phase change material PCM is chosen so that Tpcm is of the order of 25°C, i.e. significantly lower than the type A temperature of 20°C.This results in a significant reduction or even elimination of the energy consumption of station 200 to cool the H2 upstream of vehicle 1000.

[0053] The device also has derivations.

[0054] A bypass or discharge conduit 13 for the turbine 20, shown in [Fig. 1], is arranged between its inlet 12 and its outlet 22 and controlled by a turbine valve 15, so as to protect the turbine 20 and regulate the mass flow of H2 passing through it.

[0055] On the low pressure branch a first bypass conduit 23 of the thermal energy storage 40 TESS is arranged between its first inlet 22 and outlet 43 and controlled by a first valve 25, so as to regulate the mass flow of H2 passing through this portion of the TESS.

[0056] Similarly, on the high pressure branch a second bypass conduit 203 of the TESS is arranged between its second inlet 202 and outlet 41 and controlled by a second valve 205, so as to regulate the mass flow rate of H2 passing through this portion of the TESS.

[0057] Neglecting kinetic and potential energies, as well as thermal losses and friction, and assuming adiabatic expansion, the isentropic efficiency of the turbine is expressed by the ratio of enthalpy variations, where the numerator (Hdefhp - Hdeflp) represents the specific work of the expansion, and where the denominator (Hdefhp - Hdeflpisentropic) takes into account isentropic expansion.

[0058] The specific cooling capacity of expanded H2 is provided by (Hdefin -Hdeflp), and the cooling requirement of high pressure H2 from Tfh to Tfc during filling is expressed by (Hfh- Hfc).

[0059] The increase in efficiency allowed by the additional work provided by the expansion of H2 is the quotient between a numerator (Hdefhp - Hdeflp) which represents the specific work of the expansion, and a denominator PCIh2 which is the lower calorific value of the dihydrogen.

[0060] For a given efficiency of the turbine 20, the work recovered from the expansion decreases with the pressure in the H2 10 tank (in particular when it empties while driving) and similarly, at a given pressure in the H2 10 tank, the work recovered is directly proportional to the efficiency of the turbine 20.

[0061] Preliminary calculations make it possible to estimate, for different turbine efficiencies, the recovered work and the cooling capacity: at 35% and 60% respectively, the specific work is approximately 1.1 MJ / kg and 1.8 MJ / kg respectively, while the cooling potential is practically zero at 35% and approximately 800 kJ / kg at 60% turbine efficiency. The cooling requirement from +20°C to -20°C of H2 under 700 bar being 600 kJ / kg (neglecting the thermal losses in the 40 TESS thermal energy storage and in all the H2 pipes as well as the various frictions), this requirement is satisfied for a turbine efficiency substantially greater than 50%. For a turbine efficiency of 35% to 50%, the implemented system makes it possible to reduce the energy consumption of H2 cooling by the filling station.From the work recovered at the turbine by the expansion of H2, the efficiency gain is evaluated for different turbine efficiencies: approximately 1.0% and 1.6% additional efficiency for 35% and 60% turbine efficiency respectively, or approximately 2% and 3% reduction in H2 consumption respectively for an FCEV fuel cell electric vehicle. Assuming an unrealistic efficiency of 100% turbine efficiency, the maximum (but unattainable) efficiency gain is approximately 2.5%, or 5% reduction in H2 consumption for a . FCEV.

[0062] An improvement of the device presented above, at least to compensate for the losses not taken into account above, is possible, to satisfy type A at -20°C of the SAE J2601 standard, by using two stages of phase change materials PCM: a lower stage PCM2 remains at a transition temperature Tpcm2 of the order of -25°C, while the material of the upper stage PCM1 will be chosen so that Tpcml > Tpcm2, ideally -10°C < Tpcml <0°C.

[0063] [Fig.3] illustrates the evolution of the H2 temperatures as a result of crossing by its two inputs of the 40 TESS thermal energy storage. The interest is to be able to store more thermal energy in the 40 TESS thermal energy storage by the successive implementation of the latent heats of the two materials. Thus, the specific cooling capacity of the system is increased from 600 to 850-900 kJ / kg and the temperature of H2 at the end of the first output of the 40 TESS thermal energy storage, Tdefin, is increased from approximately -30°C to approximately -5°C to -10°C.

[0064] However, the SAE J2601 standard defines the type of filling station dispenser based on its ability to dispense cooled hydrogen to a specific temperature at the nozzle (type A: -20°C, and type B: -40°C). The coverage of type A is achievable with a device 100 according to the invention, by implementing a thermal energy storage 40 TESS with a single PCM phase change material as described above. A suitable PCM phase change material has for example the following characteristics: phase transition temperature: melting - 26°C, freezing - 26°C, nucleation -26°C. Its latent heat / enthalpy is: liquid 264 kJ / kg, solid 182 kJ / kg. Its density is: liquid 1200 kg / m3, solid 1122 kg / m3. Its specific heat is: liquid 3.6 kJ / kgK, solid 1.7 kJ / kgK.

[0065] [Fig.4] describes the proposed method for reaching a cooling temperature of -40°C. Similar to above, to meet SAE J2601 Type B at -40°C, a third stage of PCM phase change material is used: the upper stages PCM1 and PCM2 remain at the transition temperatures Tpcml and Tpcm2 similar to those before, and a third lower stage PCM3 is implemented so that the associated transition temperature Tpcm3 is substantially lower than 40°C, e.g. Tpcm3 at about 45°C. By doing so, a specific cooling capacity of about 1 MJ / kg can be achieved.

[0066] Thus, the energy recovery system according to the invention lowers the H2 consumption of the vehicle 1000, by supplying energy via the turbine 20, and reduces or cancels the energy consumption by the H2 filling station 200 linked to the cooling of the H2. To make this possible, a bidirectional communication protocol is implemented between the vehicle 1000 and the filling station in H2 200, so that the vehicle 1000 controls the H2 cooling system of the filling station in H2 200. Furthermore, the fuel consumption gain is of the same order of magnitude as that achieved by a heat recovery loop by Rankine cycle, which, by implementing many more components (turbine, fluid pump, heat exchangers, in addition to a dedicated turbine) would be much more complex and expensive. In addition, the sections of the on-board thermal energy storage system 40 TESS at very low temperature can also act as a cold source to improve the cooling capacity of the air conditioning of the vehicle 1000, to refrigerate the passenger compartment and / or cool the electrochemical traction storage unit.

[0067] [Fig.5] illustrates an automobile network 2000 comprising a plurality of such vehicles automobiles 1000, and a plurality of such dihydrogen pumps 200. According to the invention, each device 100 for recovering the energy from the compression of dihydrogen is arranged to communicate with each dihydrogen pump 200, according to a bidirectional communication protocol arranged so that the vehicle 1000 controls the dihydrogen cooling system of the dihydrogen pump 200, and is arranged to lower the hydrogen consumption of the vehicle 1000, and reduce or cancel the energy consumption for cooling the dihydrogen by the dihydrogen pump 200.

[0068] More particularly, the only systems for cooling the dihydrogen of this automobile network 2000 are the devices 100 for recovering the energy from the compression of the dihydrogen that the motor vehicles 1000 of the automobile network 2000 comprise: the dihydrogen pumps 200 are then devoid of a hydrogen cooling system, or else their cooling system is deactivated or bypassed by the dihydrogen introduced into the supply pipe 201 of the vehicle 1000. According to a variant, the cooling system of the hydrogen pumps 200 only provides cooling complementary to that operated by each device 100.

[0069] The invention also relates to a method for recovering energy on a motor vehicle 1000 comprising at least one fuel cell 50 or at least one dihydrogen internal combustion engine 60, arranged to consume dihydrogen. According to the invention, this motor vehicle 1000 is equipped with a device 100 for recovering the compression energy of the dihydrogen, which device 100 comprises, on the one hand, a turbine 20 which is interposed between at least one dihydrogen tank 10 on board this motor vehicle 1000 and a service pipe 44 arranged to deliver dihydrogen under temperature and pressure conditions required by this at least one fuel cell 50 or by this at least one dihydrogen internal combustion engine 60, and, on the other hand, an on-board system thermal energy storage system 40 based on at least one phase change material, between a high-pressure hydrogen line comprising a supply pipe 201 arranged to be connected to a dihydrogen pump 200 external to the motor vehicle 1000 and to supply dihydrogen to the dihydrogen tank 10, and a low-pressure hydrogen line between the turbine 20 and the service pipe 44. And each phase change material is chosen so that its transition temperature Tpcm is higher than the temperature Tdeflp of the dihydrogen at the outlet of the turbine 20 with a difference that is calculated so that the phase change material undergoes a phase transition.

[0070] More particularly, said on-board thermal energy storage system 40 is equipped with several stages of phase-change materials, with different characteristics and different transition temperatures, so as to store in said on-board thermal energy storage system 40 thermal energy accumulated by the successive use of the latent heats of the different phase-change materials that this on-board thermal energy storage system 40 comprises.

[0071] The economic interest of the invention is significant: improvement of the overall efficiency of the powertrain and reduction of the H2 consumption of the vehicle, simple and inexpensive system, recovery and storage of the thermal energy from the compression of the H2 during filling and its restitution to the low pressure H2 distributed at the inlet, depending on the case of the FC fuel cell or the H2ICE dihydrogen internal combustion engine, and improvement of the dynamic performance of the vehicle in particular at low ambient temperatures.

[0072] In summary, the turbine installed to recover at least part of the H2 expansion work produces additional power which improves the overall efficiency of the traction chain, in a simpler and less expensive way than a thermodynamic cycle such as that of Rankine for example.

[0073] The on-board thermal energy storage system TESS makes it possible to recover and store at least part of the thermal energy from the compression of the H2 during filling and to restore it, during the driving following this filling, to the low-pressure H2 distributed at the inlet of the FC fuel cell or the H2ICE dihydrogen internal combustion engine, this in order to improve the dynamic performance of the vehicle (in particular and not limited to autonomy, acceleration and recovery) in particular at low ambient temperatures.

[0074] In summary, the invention provides significant advantages, both for the filling station manager and vehicle users: reduction of energy consumption and cost of cooling H2 by the filling station before filling the tank; recovery and use within the vehicle of the associated thermal energy, conventionally lost; recovery of H2 compression energy, in particular up to 700 bar, conventionally lost; improved overall vehicle efficiency.

Claims

Claims

1. Motor vehicle (1000) comprising at least one fuel cell (50) or at least one dihydrogen internal combustion engine (60), arranged to consume dihydrogen, said motor vehicle (1000) comprising a high-pressure hydrogen line which comprises a supply pipe (201) arranged to be connected to a dihydrogen pump (200) external to said motor vehicle (1000) for supplying said motor vehicle (1000) with dihydrogen, said supply pipe (201) being arranged to supply dihydrogen to a tank inlet pipe (42) for supplying dihydrogen to at least one dihydrogen tank (10) on board said motor vehicle (1000) and at the outlet of which at least one dihydrogen tank (10) a high-pressure pipe (11) supplies a turbine (20) coupled to an alternator (30) for recovery of energy,and at the outlet of which turbine (20) said motor vehicle (1000) comprises a low-pressure hydrogen line which comprises a low-pressure pipe (21) arranged to supply, at a service pipe (44), dihydrogen under temperature and pressure conditions required by said at least one fuel cell (50) or by said at least one dihydrogen internal combustion engine (60) which said motor vehicle (1000) comprises, characterized in that said motor vehicle (1000) comprises a device (100) for recovering the compression energy of the dihydrogen, which comprises on the one hand said turbine (20), and, on the other hand an on-board thermal energy storage system (40) based on phase-change material, between said high-pressure hydrogen line and said low-pressure hydrogen line.,

2. Motor vehicle (1000) according to claim 1 characterized in that said turbine (20) is arranged to carry out an expansion of the dihydrogen which passes through it, from a high pressure (Pdefhp) in said high pressure pipe (11) to a low pressure (Pdeflp) in said low pressure pipe (21), said expansion of the dihydrogen making it possible to lower its temperature from a high pressure temperature (Tdefhp) in said high pressure pipe (11) to a low pressure temperature (Tdeflp) in said low pressure pipe (21), and in that said on-board thermal energy storage system (40) is arranged to collect energy thermal energy coming from the dihydrogen downstream of said low pressure tubing (21), at a first inlet (22) of said on-board thermal energy storage system (40) by at least one said phase change material chosen so that its transition temperature (Tpcm) is higher than said low pressure temperature (Tdeflp) with a predetermined gap to allow a phase transition of each said phase change material.

3. Motor vehicle (1000) according to any one of claims 1 to 2, characterized in that said on-board thermal energy storage system (40) comprises several stages of phase change materials, of different characteristics and different transition temperatures, so as to store thermal energy in said on-board thermal energy storage system (40) by the successive use of the latent heats of the different phase change materials that said on-board thermal energy storage system (40) comprises.

4. Motor vehicle (1000) according to any one of claims 2 to 3, characterized in that said device (100) for recovering the energy from the compression of dihydrogen comprises a discharge conduit (13) for said turbine (20), arranged between said high-pressure pipe (11) at the tank outlet and said first inlet (22) of said on-board thermal energy storage system (40), said conduit (13) being controlled by a turbine valve (15), so as to protect said turbine (20) and regulate the mass flow of hydrogen passing through it.

5. Motor vehicle (1000) according to any one of claims 1 to 4 characterized in that said device (100) for recovering the compression energy of dihydrogen comprises, on said low pressure hydrogen line, a first bypass conduit (23) of said on-board thermal energy storage system (40) which is arranged between said low pressure pipe (21) and said service pipe (44), and in that said first bypass conduit (23) is controlled by a first valve (25), so as to regulate the mass flow rate of hydrogen passing through a low pressure portion of said on-board thermal energy storage system (40).

6. Motor vehicle (1000) according to any one of claims 1 to 5 characterized in that said device (100) for recovering the energy from the compression of dihydrogen comprises, on said high pressure hydrogen line, a second bypass conduit (203) of said on-board thermal energy storage system (40) which is arranged between a second inlet (202) of said on-board thermal energy storage system (40) downstream of said dihydrogen supply pipe (201), and a second outlet (41) of said on-board thermal energy storage system (40) upstream of said tank inlet pipe (42), and in that said second bypass pipe (203) is controlled by a second valve (205), so as to regulate the mass flow of hydrogen passing through a high-pressure portion of said on-board thermal energy storage system (40).

7. Automotive network (2000) comprising a plurality of motor vehicles (1000) according to any one of claims 1 to 6, and a plurality of said dihydrogen pumps (200), characterized in that each device (100) for recovering the energy from compression of the dihydrogen is arranged to communicate with each said dihydrogen pump (200), according to a bidirectional communication protocol arranged so that said vehicle (1000) controls the dihydrogen cooling system of said dihydrogen pump (200), and is arranged to lower the hydrogen consumption of said vehicle (1000), and reduce or cancel the energy consumption for cooling the dihydrogen by said dihydrogen pump (200).

8. Automotive network (2000) according to claim 7 characterized in that the only systems for cooling the dihydrogen of said automotive network (2000) are said devices (100) for recovering the compression energy of the dihydrogen that said motor vehicles (1000) of said automotive network (2000) comprise.

9. Method for recovering energy on a motor vehicle (1000) comprising at least one fuel cell (50) or at least one dihydrogen internal combustion engine (60), arranged to consume dihydrogen, characterized in that said motor vehicle (1000) is equipped with a device (100) for recovering the compression energy of the dihydrogen, which device (100) comprises on the one hand a turbine (20) which is interposed between at least one dihydrogen tank (10) on board said motor vehicle (1000) and a service pipe (44) arranged to deliver dihydrogen under temperature and pressure conditions required by said at least one fuel cell (50) or by said at least one dihydrogen internal combustion engine (60), and, on the other hand, an on-board storage system thermal energy (40) based on at least one phase change material, between a high pressure hydrogen line comprising a supply pipe (201) arranged to be connected to a dihydrogen pump (200) external to said motor vehicle (1000) and to supply dihydrogen to said at least one dihydrogen tank (10), and a low pressure hydrogen line between said turbine (20) and said service pipe (44), and in that each said at least one phase change material is chosen so that its transition temperature (Tpcm) is higher than the temperature (Tdeflp) of the dihydrogen at the outlet of said turbine (20) with a difference which is calculated so that said phase change material undergoes a phase transition.

10. Method according to claim 9, according to which said on-board thermal energy storage system (40) is equipped with several stages of phase change materials, of different characteristics and different transition temperatures, so as to store in said on-board thermal energy storage system (40) thermal energy accumulated by the successive use of the latent heats of the different phase change materials which said on-board thermal energy storage system (40) comprises.

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