Claims:We Claim:

1. A heat recovery system (100) for a hydrogen fuel cell, the system (100) comprising:
at least one fuel tank (1) adapted to receive and store hydrogen;
at least one fuel cell module (2) configured to receive hydrogen from the at least one fuel tank (1);
an energy conversion unit (200) fluidly coupled to the at least one fuel tank (1) and the at least one fuel cell module (2);
a control unit (16), wherein the control unit (16) is configured to:
selectively route a first fluid either from the at least one fuel tank (1) and the at least one fuel cell module (2) to the energy conversion unit (200) for converting heat generated in the at least one fuel tank (1) and the at least one fuel cell module (2) to electricity.

2. The system (100) as claimed in claim 1 comprises a first circuit (8) connected to auxiliary devices (10) and configured to facilitate the flow of the first fluid and for absorbing heat from the auxiliary devices (10).

3. The system (100) as claimed in claim 1 comprises, a second circuit (9) extending from the first circuit (8) and configured to facilitate the flow of the first fluid.

4. The system (100) as claimed in claim 3 wherein, the second circuit (9) is configured through the at least one fuel tank (1) and the at least one fuel cell module (2) for absorbing heat.

5. The system (100) as claimed in claim 1 comprises, a first valve (12) configured at a junction where the first circuit (8) extends from the second circuit (9) for re-directing the first fluid from the first circuit (8) to the second circuit (9) connected to the at least one fuel tank (1).

6. The system (100) as claimed in claim 1 wherein, the control unit (16) is connected to the first valve (12) and operates the first valve (12) to re-direct the first fluid from the first circuit (8) to the second circuit (9) when the control unit (16) receives a signal corresponding to a re-fueling condition of the hydrogen fuel cell.
7. The system (100) as claimed in claim 1 wherein, the control unit (16) is connected to the first valve (12) and operates the first valve (12) to allow the flow of fluid in first circuit (8) to the at least one fuel cell module (2) when the control unit (16) receives a signal corresponding to an operational condition of the hydrogen fuel cell.

8. The system (100) as claimed in claim 1 comprises, a temperature-controlled valve (14) wherein, an inlet of the temperature-controlled valve (14) is configured to receive the first fluid from the at least one fuel cell module and the outlet of the temperature-controlled valve (14) is fluidly coupled to the first circuit (8) and the second circuit (9).

9. The system (100) as claimed in claim 1 wherein, the temperature-controlled valve (14) is connected to the control unit (16) to re-direct the first fluid from the at least one fuel cell module into one of the first circuit (8) or the second circuit (9) based on the temperature of the first fluid.

10. The system (100) as claimed in claim 1 comprises, a radiator (3) connected to the first circuit (8) for dissipating the heat from the first fluid in the first circuit (8).

11. The system (100) as claimed in claim 1 wherein, the energy conversion unit (200) comprises:
a heat exchanger (4) configured to transfer heat from the first fluid in the second circuit (9) to a second fluid in a third circuit (17);
wherein, the second fluid absorbs the heat from the first fluid and is evaporated;
a generator (5) configured to receive the second and generate electricity; and
a condenser (6) configured to receive the second fluid and condense the second fluid.

12. The system (100) as claimed in claim 1 wherein, the generator (5) is connected to a battery for storing the generated electricity.

13. A method for recovering heat from a hydrogen fuel cell system, the method comprising:
receiving by a control unit (16), a signal corresponding to a re-fueling condition or an operational condition of the hydrogen fuel cell system;
operating by the control unit (16), a first valve (12) for directing a first fluid to at least one fuel tank (1) and for absorbing heat from the at least one fuel tank (1) when the signal received by the control unit (16) corresponds to the re-fueling condition;
wherein, the first fluid is directed to an energy conversion unit from the at least one fuel tank (1) for conversion of heat into electricity;
operating by the control unit (16), a second valve (13) for directing a first fluid to at least one fuel cell module (2) and for absorbing heat from the at least one fuel cell module (2) when the signal received by the control unit (16) corresponds to the operational condition;
wherein, the first fluid is directed to the energy conversion unit (200) from the at least one fuel cell module (2) for conversion of heat into electricity.

14. The method as claimed in claim 13 wherein, the control unit (16) is configured to operate a first valve (12) for re-directing the first fluid from the first circuit (8) to the second circuit (9) connected to the at least one fuel tank (1) when the control unit (16) receives the signal corresponding to the re-fueling condition of the hydrogen fuel cell.
.
15. The method as claimed in claim 13 wherein, the control unit (16) is configured to operate the first valve (12) to allow the flow of fluid in first circuit (8) and to the at least one fuel cell module (2) when the control unit (16) receives the signal corresponding to the operational condition of the hydrogen fuel cell.

16. The method as claimed in claim 13 wherein, the control unit (16) operates a temperature-controlled valve (14) to re-direct the first fluid from the at least one fuel cell module (2) into one of the first circuit (8) or the second circuit (9) based on the temperature of the first fluid.

17. The method as claimed in claim 16 wherein, the control unit (16) operates a temperature-controlled valve (14) to re-direct the first fluid from the at least one fuel cell module (2) into the first circuit (8) when the temperature of the fluid is below a pre-determined threshold limit.

18. The method as claimed in claim 16 wherein, the control unit (16) operates a temperature-controlled valve (14) to re-direct the first fluid from the at least one fuel cell module (2) into the second circuit (9) when the temperature of the fluid is above a pre-determined threshold limit.

19. The method as claimed in claim 13 wherein, the method of converting heat from the first fluid into electricity by the energy conversion unit (200) comprises:
evaporating a second fluid in a heat exchanger (4) configured to transfer heat from the first fluid in the second circuit (9) to the second fluid in a third circuit (17);
converting by a generator (5), the heat from the second fluid into generate electricity; and
condensing the second fluid by a condenser (6).
, Description:TECHNICAL FIELD

Present disclosure generally relates to a field of automobiles. Particularly but not exclusively present disclosure relates to a hydrogen fuel cell system. Further, embodiments of the present disclosure disclose a heat recovery system for the hydrogen fuel cell system.

BACKGROUND OF THE INVENTION

Fuel cell is an electrochemical cell which converts chemical energy of a fuel into an electrical energy. Unlike a conventional battery, the fuel cell may continuously produce electricity as long as fuel in the form of hydrogen and air are supplied thereto. The fuel cell system may generally comprise a fuel cell stack for generating electricity, a fuel supply system for supplying fuel like hydrogen to the fuel cell stack, an air supply system for supplying oxygen. The oxygen may act as an oxidizing agent required for an electrochemical reaction, in the fuel cell stack.

With the depletion of non-renewable energy, fuel cells are expected to play a major role as a sustainable technology for power generation in wide variety of applications. One such application may be automotive applications. The fuel cell which may be considered as future automotive propulsion applications may be a Polymer Electrolyte Membrane Fuel Cell (PEMFC). The PEMFC system is an energy system that converts hydrogen and oxygen (or air) to electricity with water as by-product, and hence is of great interest from an environmental point of view. The process of generation of electricity from hydrogen and oxygen in the fuel cell generates heat. This heat may generally be absorbed by a coolant and the heat from the coolant may further be dissipated to the atmosphere. Consequently, a significant amount of energy is rendered futile.

Generally, heat is generated in a fuel tank when the hydrogen is being refueled. Hydrogen is often required to be pre-cooled to prevent overheating while being filled into the vehicle tank. The hydrogen gas in the tank generates heat because it is compressed while being filled. During the refueling process, the compressed state of the hydrogen gas leads to a warming of the gas inside the tank. The temperature of the cooled hydrogen may also rise due to pressure loss and external heat transfer. The final temperature within the tank can have an impact on the safety but also on the level of filling of the tank. Generally, the fuel tanks that store hydrogen are designed to work between -40 °C and 85 °C. A temperature of the hydrogen gas beyond 85 °C becomes a safety hazard. Further, higher temperatures of the hydrogen gas in the fuel tank may also result in increased re-fueling time. The re-fueling time of hydrogen increases at higher temperatures of the tank for mitigation of safety at fuel stations.

The present disclosure is directed to overcome one or more limitations stated above, or any other limitation associated with the prior arts.

SUMMARY OF THE DISCLOSURE

One or more shortcomings of the conventional system or device are overcome, and additional advantages are provided through the provision of the device as claimed in the present disclosure.

Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the claimed disclosure.

In a non-limiting embodiment of the disclosure, a heat recovery system for a hydrogen fuel cell is disclosed. The system includes at least one fuel tank adapted to receive and store hydrogen. At least one fuel cell module is configured to receive hydrogen from the at least one fuel tank. An energy conversion unit is fluidly coupled to the at least one fuel tank and the at least one fuel cell module. Further, a control unit is configured to selectively route a first fluid either from the at least one fuel tank and the at least one fuel cell module to the energy conversion unit for converting heat generated in the at least one fuel tank and the at least one fuel cell module to electricity.

In an embodiment of the disclosure, a first circuit is connected to auxiliary devices and is configured to facilitate the flow of the first fluid and for absorbing heat from the auxiliary devices.

In an embodiment of the disclosure, a second circuit extends from the first circuit and is configured to facilitate the flow of the first fluid.

In an embodiment of the disclosure, the second circuit is configured through the at least one fuel tank and the at least one fuel cell module for absorbing heat.

In an embodiment of the disclosure, a first valve is configured at a junction where the first circuit extends from the second circuit for re-directing the first fluid from the first circuit to the second circuit connected to the at least one fuel tank.

In an embodiment of the disclosure, the control unit is connected to the first valve and operates the first valve to re-direct the first fluid from the first circuit to the second circuit when the control unit receives a signal corresponding to a re-fueling condition of the hydrogen fuel cell.

In an embodiment of the disclosure, the control unit is connected to the first valve and operates the first valve to allow the flow of fluid in first circuit to the at least one fuel cell module when the control unit receives a signal corresponding to an operational condition of the hydrogen fuel cell.

In an embodiment of the disclosure, a temperature-controlled valve is provided where, an inlet of the temperature-controlled valve is configured to receive the first fluid from the at least one fuel cell module and the outlet of the temperature-controlled valve is fluidly coupled to the first circuit and the second circuit.

In an embodiment of the disclosure, the temperature-controlled valve is connected to the control unit to re-direct the first fluid from the at least one fuel cell module into one of the first circuit or the second circuit based on the temperature of the first fluid.

In an embodiment of the disclosure, a radiator connected to the first circuit for dissipating the heat from the first fluid in the first circuit.

In an embodiment of the disclosure, the energy conversion unit includes a heat exchanger configured to transfer heat from the first fluid in the second circuit to a second fluid in a third circuit. The second fluid absorbs the heat from the first fluid and is evaporated. Further, a generator is configured to receive the second fluid and generate electricity and a condenser configured to receive the second fluid and condense the second fluid.

In an embodiment of the disclosure, the generator is connected to a battery for storing the generated electricity.

In a non-limiting embodiment of the disclosure, a method for recovering heat from a hydrogen fuel cell system is disclosed. The method includes steps of receiving, a signal corresponding to a re-fueling condition or an operational condition of the hydrogen fuel cell by a control unit. The control unit subsequently operates a first valve for directing a first fluid to at least one fuel tank and for absorbing heat from the at least one fuel tank when the signal received by the control unit corresponds to the re-fueling condition. The first fluid is directed to an energy conversion unit from the at least one fuel tank for conversion of heat into electricity. The control unit also operates a second valve for directing the first fluid to at least one fuel cell module and for absorbing heat from the at least one fuel cell module when the signal received by the control unit corresponds to the operational condition. The first fluid is directed to the energy conversion unit from the at least one fuel cell module for conversion of heat into electricity.

In an embodiment of the disclosure, the control unit is configured to operate a first valve for re-directing the first fluid from the first circuit to the second circuit connected to the at least one fuel tank when the control unit receives the signal corresponding to the re-fueling condition of the hydrogen fuel cell.

In an embodiment of the disclosure, the control unit is configured to operate the first valve to allow the flow of fluid in first circuit and to the at least one fuel cell module when the control unit receives the signal corresponding to the operational condition of the hydrogen fuel cell.

In an embodiment of the disclosure, the control unit operates a temperature-controlled valve to re-direct the first fluid from the at least one fuel cell module into one of the first circuit or the second circuit based on the temperature of the first fluid.

In an embodiment of the disclosure, the control unit operates a temperature-controlled valve to re-direct the first fluid from the at least one fuel cell module into the first circuit when the temperature of the fluid is below a pre-determined threshold limit.

In an embodiment of the disclosure, the control unit operates a temperature-controlled valve to re-direct the first fluid from the at least one fuel cell module into the second circuit when the temperature of the fluid is above a pre-determined threshold limit.

In an embodiment of the disclosure, the method of converting heat from the first fluid into electricity by the energy conversion unit includes aspects of evaporating a second fluid in a heat exchanger which is configured to transfer heat from the first fluid in the second circuit to the second fluid in a third circuit. Subsequently, the heat from the second fluid is converted into electricity by a generator and the second fluid is further condensed by a condenser.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE ACCOMPANYING FIGURES

The novel features and characteristic of the disclosure are set forth in the appended claims. The disclosure itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:

Fig. 1 is a schematic representation of a heat recovery system for a hydrogen fuel cell, in accordance with an embodiment of the present disclosure.

Fig. 2 illustrates a block diagram of the heat recovery system for the hydrogen fuel cell, in accordance with an embodiment of the present disclosure.

Fig. 3 is a flowchart of a method of recovering heat from a hydrogen fuel cell, in accordance with an embodiment of the present disclosure.

The figure depicts embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the system for recovering heat in the hydrogen fuel cell illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION

The foregoing has broadly outlined the features and technical advantages of the present disclosure in order that the description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter which form the subject of the disclosure. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other devices for carrying out the same purposes of the present disclosure. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the disclosure. The novel features which are believed to be characteristic of the disclosure, as to its organization, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present disclosure.

In the present document, the word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any embodiment or implementation of the present subject matter described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.

While the disclosure is susceptible to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the drawings and will be described below. It should be understood, however that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternative falling within the scope of the disclosure.

The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a system that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such mechanism. In other words, one or more elements in the device or mechanism proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the mechanism.

The following paragraphs describe the present disclosure with reference to Figs. 1 to 3. In the figures, the same element or elements which have same functions are indicated by the same reference signs. It is to be noted that, the vehicle is not illustrated in the figures for the purpose of simplicity. One skilled in the art would appreciate that the system and the method as disclosed in the present disclosure may be used in any vehicles that employs/includes at least one hydrogen fuel cell, where such vehicle may include, but not be limited to, light duty vehicles, passenger vehicles, commercial vehicles, and the like. Further, the person skilled in the art would appreciate that the system and the method as disclosed in the present disclosure may be used in any power generation devices which are run on hydrogen fuel cells and must not be limited to vehicles.

Fig. 1 is a schematic representation a heat recovery system (100) for a hydrogen fuel cell. The hydrogen fuel cell for generating electricity, may include at least one fuel tank (1) [hereinafter referred to as the fuel tank]. The fuel tank (1) may be configured to receive and store hydrogen in a fluid form. The fuel tank (1) may also be configured with at least one first temperature sensors (1a) [hereinafter referred to as the first temperature sensor] for detecting an overall temperature of the tank. The first temperature sensor (1a) may be connected to a control unit (16) [shown in Fig 2] and the control unit (16) may receive signals from the first temperature sensor (1a) that corresponds to the temperature of the fuel tank (1). The fuel tank (1) may also be configured with a valve [not shown] and the valve may be operated by the control unit (16). The control unit (16) may selectively operate the valve to release hydrogen from the fuel tank (1) for generation of electricity.

The hydrogen fuel cell may also include at least one fuel cell module (2) [hereinafter referred to as the fuel cell module]. The fuel cell module (2) may include multiple fuel cells. Each of the fuel cell in the fuel cell module (2) may include two bi-polar plates, where one of the plate is an anode, whereas the other plate is the cathode. In the exemplary configuration of the fuel cell, a first plate may be configured as hydrogen side plate and a second plate may be configured as an air side plate, and these two plates together form the bipolar plate assembly. Fig. 2 illustrates a block diagram of the heat recovery system (100) for recovering heat in the hydrogen fuel cell. The first plate through which the hydrogen is circulated acts as the anode, whereas the second plate through which air is circulated acts as a cathode. As the hydrogen is circulated through the first plate, the hydrogen may come in contact with a catalyst. The catalyst separates the hydrogen into positively charged hydrogen ions and electrons. These positively charged hydrogen ions and electrons further diffuse from the catalyst and come in contact with the proton exchange membrane. The proton exchange membrane allows only the positively charged hydrogen ions to pass through, whereas the flow of electrons may be blocked. The electrons may thus be forced to flow through an external circuit by means of the current collectors. The positively charged hydrogen ions travel through the proton exchange membrane and reach another catalyst, whereas the electrons flow from the current collector near the first plate to the current collector near the second plate through an external circuit, thereby generating electricity. This electricity may be used for suitable productive purposes such as driving an electric motor in a vehicle. The above-described working of the fuel cell is only exemplary in nature and must not be considered as a limitation. Any configuration of the fuel cell and process of generation of electricity from the fuel cell may be adapted herein. In a preferable embodiment, the flow of hydrogen from the fuel tank (1) to the fuel cell module (2) may be facilitated by a fluid flow line and the control unit (16) may operate the valve connected to the fuel tank (1) for regulating the flow of hydrogen from the fuel tank (1) to the fuel cell module (2).

The control unit (16) may also be connected to multiple sensors which transmit signals corresponding to a re-fueling condition of the fuel tank (1) and the operational condition of the fuel cell module (2). For instance, the fuel tank (1) may be provided with a sensor along an inlet hose. An external coupling to the inlet hose of the fuel tank (1) may cause the sensor to transmit a signal to the control unit (16) and the control unit (16) may subsequently interpret this signal to be an indication of the re-fueling condition of the vehicle. In an embodiment, the detection of the re-fueling condition of the fuel tank (1) must not be limited to the sensor at the inlet hose and any other sensors which detect and transmit a signal when the fuel tank (1) is being re-fueled with hydrogen may be used. For instance, the first temperature sensor (1a) which indicates the temperature of the fuel tank (1) may also be used to determine the re-fueling condition of the vehicle. When the first temperature sensor (1a) transmits a signal to the control unit (16) that corresponds to a temperature beyond a pre-determined threshold, the control unit (16) may interpret that the fuel tank (1) is being re-fueled. Further, the control unit (16) may also be connected to multiple sensors which transmit signals corresponding to the operational condition of the fuel cell module (2). For instance, the fuel cell module (2) may be provided with a sensor that detects the generation of electricity from the fuel cell module (2). Subsequently, the sensor may transmit a signal to the control unit (16) and the control unit (16) may interpret this signal as an indication of the operational state of the fuel cell module (2). In an embodiment, the detection of the operational condition of the fuel cell module (2) must not be limited to the sensor for detecting electricity from the fuel cell module (2) and any other sensors which detect and transmit a signal when the fuel cell module (2) is in an operational condition may be used.

In an embodiment, the fuel tank (1) may be made from any material including but not limited to composite material, fiber glass or aramid or carbon fiber with a metal liner and the metal liner may be made of aluminum or steel. In an embodiment, the fuel cell module (2) may be any type including but not limited to polymer electrolyte membrane fuel cell, direct methanol fuel cells, reversible fuel cells, alkaline fuel cells etc.

In a preferable and exemplary embodiment, the hydrogen fuel cell may include multiple auxiliary devices (10) [hereinafter referred to as the auxiliary devices]. The auxiliary devices (10) may be devices including but not limited to batteries, AC/DC converters, inverters, motors etc. In this embodiment, the auxiliary devices (10) may be the devices that are used in the vehicle. The battery as the auxiliary device (10) may be used to store the electric energy generated from the fuel cell module (2). Further, the electricity may be converted to the required form through the AC/DC convertor and the motor may be energized by the electricity from the battery to drive the vehicle. These auxiliary devices (10) during their operational stage may often generate a large amount of heat. This heat needs to be contained below a pre-determined threshold limit for providing optimal working conditions of the auxiliary devices (10). A coolant may be circulated through the auxiliary devices (10) for absorbing the heat through the auxiliary devices (10). The coolant may absorb the heat from the auxiliary devices (10) and may provide the required operational conditions by reducing and maintain the temperature of the auxiliary devices (10). Further, the coolant may also be circulated for absorbing heat from the fuel tank (1) and the fuel cell module (2).

In an embodiment, the type of auxiliary devices (10) must not be considered as a limitation. For instance, the battery may herein be of any type including but not limited to lithium ion, lead acid etc. Similarly, the constructional configuration of the motors or the inverters must not be considered as a limitation since, any type of motors or inverters may be used. In an embodiment, the coolant that is circulated to each of the auxiliary devices (10) may be circulated in a loop. For instance, the coolant may initially flow through the AC/DC converter and may subsequently flow though the inverter. The coolant may further be configured to flow through the motor and the battery. However, the above illustrated flow path must not be considered as a limitation. In an embodiment, each of the auxiliary devices (10) may include a temperature sensor and the temperature sensor may be connected to the control unit (16). The control unit (16) may selectively route the flow of coolant between each of the auxiliary devices (10) based on the temperature of the auxiliary devices (10). For instance, if the temperature of the battery is above a pre-determined threshold limit and if the temperature of the motor is in the required optimal operational range, the control unit (16) may selectively route the flow of coolant through the battery and may bypass the flow of coolant through the motor. In an embodiment, the coolant may be configured to flow through the auxiliary devices (10) of lower temperatures and the coolant may be configured to subsequently flow through auxiliary devices (10) which operate at higher temperatures. This configuration ensures that there is significant potential for the coolant to absorb heat from each of the auxiliary devices (10). In another embodiment, individual coolant flow lines may be configured such that the coolant flow to each of the auxiliary devices is through a separate coolant line and not through other auxiliary devices (10).

The hydrogen fuel cell may further include a radiator (3) for dissipating the heat from the coolant. The radiator (3) may be positioned at any location in the vehicle which is exposed to the atmosphere. The coolant is circulated through the radiator (3) and the heat from the coolant is dissipated to the incoming air. The low temperature coolant may further be circulated to the auxiliary devices (10) for cooling the auxiliary devices (10). In an embodiment, the radiator (3) may be provided with a fan. The fan may be configured to run either at low-speed or at high-speed depending on temperature of the engine coolant. The operational speed of the fan may be controlled by the control unit (16), and speed of the fan may be regulated in accordance with temperature of the coolant. The fan may be operated in low speed when the temperature of the coolant is less than the predetermined temperature and may be operated to high speed when the temperature of the coolant exceeds the predetermined temperature. In an embodiment, the radiator (3) may diffuse the heat from the first fluid in the first circuit (8) for enabling first fluid to absorb high-grade heat from the fuel tank (1) and the fuel cell module (2).

The fluid flow path or the circuit which enables the flow of coolant through the auxiliary devices (10), the fuel cell module (2) and the fuel tank (1) is explained in detail below. The fluid flow path for absorbing heat form the auxiliary devices (10), the fuel cell module (2) and the fuel tank (1) may herein be defined as a first circuit (8) and a second circuit (9). The second circuit (9) must not be considered as a separate flow path and may herein be considered as an extension of the first circuit (8). For illustrative purposes, the first circuit (8) is herein described from a pump (11). The pump (11) may be configured to pump the coolant in the first circuit (8) and the pump (11) may be connected to the control unit (16). The control unit (16) may selectively operate the pump (11) to control the flow rate of the coolant in the first circuit (8). The coolant in the first circuit (8) may hereinafter be referred to as a first fluid. In an embodiment, the control unit (16) may operate the pump (11) based on several parameters including but not limited to the temperature of the auxiliary devices (10). For instance, if the temperature of the auxiliary devices (10) is considered to be very high, the control unit (16) may operate the pump (11) at low speeds such that the flow rate of the first fluid is also reduced. Consequently, the first fluid is circulated through the auxiliary devices (10) for a significant period of time which ensures that the heat from the auxiliary devices (10) is absorbed effectively. Further, a first valve (12) may be configured along the first circuit (8). The first circuit (8) may act as an inlet to the first valve (12). The second circuit (9) and the first circuit (8) may be configured as outlets of the first valve (12). The first valve may be operated by the control unit (16) and the control unit (16) may selectively operate the first valve (12) to direct the first fluid into the first circuit (8) or the second circuit (9). The control unit (16) may operate the first valve (12) based on the re-fueling condition of the fuel tank (1) or the operational condition of the fuel cell module (2). If the control unit (16) detects that the fuel tank (1) is being re-fueled, the control unit (16) may operate the first valve (12) to re-direct the first fluid into the second circuit (9). However, if the control unit (16) detects that fuel cell module (2) to be in the operational condition the, the control unit (16) may direct the first fluid to remain flowing through the first circuit (8). Further, a second valve (13) may be configured subsequent to the first valve (12) in the first circuit (8). The first fluid flowing from the outlet of the first valve (12) may be directed into an inlet of the second valve (13). The outlet of the second valve (13) may be configured to direct the fluid into the first circuit (8) or into the fuel cell module (2). The control unit (16) may selectively operate the second valve (13) to direct the flow of first fluid into the fuel cell module (2) or to retain the flow of first fluid in the first circuit (8). The control unit (16) may operate the second valve (13) to re-direct the flow of fluid from the first circuit (8) into the fuel cell module (2) when the control unit (16) receives the signal from the sensors which correspond to the operational condition of the fuel cell module (2). Further, if the control unit (16) does not receive any signals from the sensors which correspond to the re-fueling condition of the fuel tank (1) or the operational condition of the fuel cell module (2), the control unit (16) may operate the first valve (12) and the second valve (13) to retain the flow of the first fluid in the first circuit (8). Based on the requirement for cooling of the auxiliary devices (10) and the temperature of the auxiliary devices (10), the first fluid may be directed through the first circuit (8) and may be directed into the auxiliary devices (10) for cooling the auxiliary devices (10). As seen from Fig. 1, the first fluid is directed into the auxiliary devices (10) and the first fluid absorbs the heat from the auxiliary devices (10). Subsequently, the first fluid may re-enter the first circuit (8) at a high temperature. The first fluid may absorb the low-grade heat from the auxiliary devices (10) and is re-circulated into the first circuit (8). The first circuit (8) is also configured with the radiator (3). The first circuit (8) may be configured to extend the with multiple passes in the radiator (3). The first fluid which is flowing through the first circuit (8) and is at high temperatures is cooled by the radiator (3). The radiator (3) may enable the first circuit (8) to be exposed to the incoming air. The incoming air may absorb and dissipate the heat from the first fluid in the first circuit (8). Further, the first fluid is re-circulated back to the pump (11) through the first circuit (8).

In an embodiment, the first valve (12) and the second valve (13) may be replaced by a single valve with three outlets. This valve may be configured to selectively route the first fluid in the one of the first circuit (8), the second circuit (9) and the fuel cell module (2).

The configuration of the second circuit (9) is explained below with greater detail. As described above, the second circuit (9) extends from the first circuit (8) and the second circuit (9) also facilitates the flow of the first fluid. The second circuit (9) may extend from the first circuit (8) through the first valve (12). The second circuit (9) may be configured to extend into the fuel tank (1). As described above, the control unit (16) may operate the first valve (12) to direct the first fluid form the first circuit (8) into the second circuit (9) when the control unit (16) receives a signal from the sensor which corresponds to the re-fueling condition of the fuel tank (1). Once, the first fluid enters the second circuit (9), the first fluid and may flow towards the fuel tank (1). The second circuit (9) may be configured on the fuel tank (1) such that the first fluid flowing through the second circuit (9) is configured to absorb the heat from the fuel tank (1). During re-fueling of hydrogen into the fuel tank (1), a tremendous amount of heat is generated due to the compressed state of the hydrogen. During the refueling process, the compressed state of the hydrogen gas leads to warming of the hydrogen gas inside the tank. The first fluid in the second circuit (9) absorbs this high-grade heat from the fuel tank (1). The first fluid is further circulated to an energy conversion unit (200) through the second circuit (9) as indicated through the dotted lines in the Fig. 1. The energy conversion unit (200) may convert the heat from the first fluid into electricity.

In an embodiment, the first circuit (8) may be configured to facilitate the flow of the first fluid that absorbs low grade heat from the auxiliary devices. Further, the second circuit (9) that extends from the first circuit (8) may be configured to facilitate the flow of first fluid that absorbs high grade heat from the fuel tank (1) and the fuel cell module (2).

Further, the control unit (16) may operate the first valve (12) and the second valve (13) to direct the first fluid into the fuel cell module (2) when the control unit (16) receives the signal from the sensor which corresponds to the operational state of the fuel cell module (2). Once, the first fluid enters the fuel cell module (2), the first fluid may absorb the heat generated by the fuel cell module (2). The configuration of second circuit (9) inside the fuel cell module (2) must not be considered as a limitation and the second circuit (9) may be configured with any pattern which ensures that the first fluid in the second circuit (9) absorbs the high-grade heat form the fuel cell module (2) in the most efficient manner. Subsequently, the first fluid which is at a high temperature may exit the fuel cell module (2) and may be directed to a temperature-controlled valve (14). The temperature-controlled valve (14) may be configured to receive the first fluid at high temperatures at the inlet. The temperature-controlled valve (14) may be configured with two outlets and one of the outlet may lead to a first flow path (14a) whereas, the other outlet may lead to a second flow path (14b). The first flow path (14a) extending as one of the outlet from the temperature-controlled valve (14) may be fluidly connected to the second circuit (9) whereas, the second flow path (14b) extending as the other outlet from the temperature-controlled valve (14) may be fluidly connected to the first circuit (8). The temperature-controlled valve (14) may be configured to direct the first fluid from the fuel cell module into the first flow path (14a) or the second flow path (14b) based on the temperature of the first fluid. If the temperature of the first fluid is lower than a pre-determined threshold limit, the temperature-controlled valve (14) may allow the flow of the first fluid from the fuel cell module (2) to the first circuit (8) and the flow of the first fluid to the second circuit (9) may be terminated. The first fluid may further merge with the fluid flowing in the first circuit (8). If the temperature of the first fluid is greater than a pre-determined threshold limit, the temperature-controlled valve (14) may allow the flow of the first fluid from the fuel cell module (2) to the second circuit (9). This high temperature second first may further be circulated to the energy conversion unit (200) for converting the high-grade heat to electricity. The configuration of the energy conversion unit (200) is explained with greater detail below.

The heat recovery system (100) for the hydrogen fuel cell includes at least one energy conversion unit (200) [hereinafter referred to as the energy conversion unit]. The energy conversion unit (200) may include at least one heat exchanger (4) [hereinafter referred to as the heat exchanger]. The heat exchanger (4) may be configured to receive the second circuit (9). The heat exchanger (4) may also be configured to receive a third circuit (17) and the third circuit (17) may facilitate the flow of a second fluid. The second fluid in a preferable and exemplary embodiment may be a Rankine fluid. The second circuit (9) and the third circuit (17) may be configured inside the heat exchanger (4) such that the heat is transferred from the high temperature first fluid to the second fluid. The second fluid in this embodiment, may vaporize and may flow towards a generator (5) in the third circuit (17). The generator (5) in this embodiment may also be an expander in the form of a turbine. The vaporized third fluid may be expanded to drive the turbine. The rotation of the turbine may be converted into electricity by the generator (5). Further, the generated electricity may be transmitted to the battery for storage or may be directly transmitted for powering other auxiliary devices (10) in the vehicle through a power line (15). The spent second fluid which is still in the vapor state may further be transmitted to a condenser (6). The condenser (6) may condense the second fluid from the vapor state into at least one of a liquid state or a semi-solid state. The third circuit (17) may also include a pump (11). The pump (11) may be configured to pressurize the second fluid in the third circuit (17). In an embodiment, the pump (11) may also be connected to the control unit (16) and the control unit (16) may selectively operate the pump (11) to increase or decrease the flow rate of the second fluid in the third circuit (17).

In an embodiment, the second circuit (9) may be configured to abut an outer surface of the fuel tank (1). The second circuit (9) may extend along the outer surface of the fuel tank (1) through multiple passes with various patterns including but not limited to zigzag or crisscross patterns. In an embodiment, the third fluid which is the Rankine fluid may be a wet or a semi-dry fluid. In an embodiment, the third fluid may be a fluid including but not limited to butane, hexane, silicon oil etc. In an embodiment, the pump (11) may be of any type including but not limited to rotary lobe pump, rotary gear pump, piston pump etc. In an embodiment, the temperature-controlled valve (14) may be a valve that is controlled by the control unit (16). For instance, a temperature sensor may be configured to measure the temperature of the first fluid from the fuel cell module (2) and the control unit (16) may be configured to receive signals corresponding to the temperature of the first fluid from the fuel cell module (2). Subsequently, the control unit (16) may operate the valve to direct the first fluid into the first flow path (14a) or the second flow path (14b) based on the detected temperature of the first fluid from the fuel cell module (2).

Fig. 3 is a flowchart of a method of recovering heat from the hydrogen fuel cell. The process of heat recover may be initiated, and the control unit (16) may subsequently check if the fuel tank is being re-fueled. The control unit (16) may receive signals from the sensors which are indicative of the re-fueling condition at step 301. During an instance when the hydrogen is being re-fueled in the fuel tank (1), the sensors positioned with the fuel tank (1) may send out a signal to the control unit (16) and the control unit (16) may interpret this signal as the condition corresponding to the re-fueling state of the fuel tank (1). During re-fueling of hydrogen into the fuel tank (1), a tremendous amount of heat is generated due to the compressed state of the hydrogen. During the refueling process, the compressed state of the hydrogen gas leads to a warming of the gas inside the tank. Further, the control unit (16) may subsequently operate the first valve (12) such that the first fluid from the first circuit (8) is re-directed into the second circuit (9) at step 303. The first fluid flows through the second circuit (9) and is directed towards the fuel tank (1). The first fluid in the second circuit (9) absorbs the high-grade heat from the fuel tank (1) when the hydrogen is being re-fueled in the fuel tank (1). Subsequently, the high temperature first fluid in the second circuit (9) may be directed to the heat exchanger (4) in the energy conversion unit (200) at step 305. The heat exchanger (4) facilitates the transfer of heat from the first fluid to the second fluid in the third circuit (17). The second fluid is further expanded for running the turbine which is connected to the generator (5). The electricity generated from the generator (5) may be stored in the battery or may be directly supplied to the auxiliary devices (10).

Further, under a circumstance where the control unit (16) does not receive a signal correspond to the re-fueling condition of the fuel tank (1), the control unit (16) may check if the fuel cell module (2) is in the operational condition at the step 302. If the control unit (16) at the step 302 fails to receive a signal which corresponds to the operational condition of the fuel cell module (2), the control unit (16) may re-start the process by checking for the re-fueling condition of the fuel tank (1). However, if the control unit (16) receives the signal from the sensors which are indicative of the operational condition of the fuel cell module (2), the control unit (16) may operate the first valve (12) and the second valve (13) at the step 304. The first valve (12) may be operated by the control unit (16) such that the first fluid remains flowing in the first circuit (8). The second valve (13) may also be operated by the control unit (16) such that the first fluid in the first circuit (8) is re-directed to flow into the fuel cell module (2). The first fluid may absorb the heat from the fuel cell module (2) when the fuel cell module (2) is in the operational condition. Further, the high temperature first fluid is then directed to the temperature-controlled valve (14). The temperature-controlled valve (14) may allow the flow of first fluid into the first circuit (8) through the second flow path (14b) when the temperature of the first fluid from the fuel cell module (2) is below the pre-determined threshold limit. However, if the temperature of the first fluid from the fuel cell module (2) is above the pre-determined threshold limit, the temperature-controlled valve (14) may allow the first fluid to flow into the second circuit (9) through the first flow path (14a). Subsequently, the high temperature first fluid in the second circuit (9) may be directed to the heat exchanger (4) in the energy conversion unit (200) at step 305. The heat exchanger (4) facilitates the transfer of heat from the first fluid to the second fluid in the third circuit (17). The second fluid is further expanded for running the turbine which is connected to the generator (5). The electricity generated from the generator (5) may be stored in the battery or may be directly supplied to the auxiliary devices (10).

In an embodiment, the high temperature first fluid in the second circuit (9) which exits the fuel tank (1), or the fuel cell module (2) may be re-directed away from the energy conversion unit (200). For instance, in regions with colder temperatures, the temperature in the cabin of the vehicle may also fall below a preferred level. Subsequently, the user may find it extremely uncomfortable to be seated within the cabin. Under such circumstances, the control unit (16) may monitor the temperature of the cabin and when the temperature within the cabin drops below a pre-determined threshold limit, the control unit (16) may re-direct the high temperature first fluid towards the cabin. The control unit (16) may operate a valve and may bypass the first fluid from flowing into energy conversion unit (200). The control unit (16) may enable the flow of the high temperature first fluid into channels that are configured around the cabin of the vehicle and may consequently heat the cabin of the vehicle to required temperatures. In another embodiment, the control unit (16) may also direct the high temperature first fluid to other components/auxiliary devices (10) which are required to be heated to ensure optimal working conditions.

In an embodiment, the present disclosure harnesses the waste heat energy in the hydrogen fuel cell. The present disclosure provides a configuration for effective conversion of waste heat into electricity in the hydrogen fuel cell. Consequently, the heat energy generated during the course of operation in the hydrogen fuel cell is not rendered futile and is effectively converted to a useful form. In an embodiment, the conversion of heat energy to electricity and subsequent storage of electricity in batteries provides a longer range to the vehicle and also improves the overall efficiency of the hydrogen fuel cell. In an embodiment, the absorption of energy from the fuel tank (1), enables faster re-fueling rates of hydrogen.

Equivalents

With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

It will be understood by those within the art that, in general, terms used herein, are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "includes" should be interpreted as "includes but is not limited to," etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding the description may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a" and/or "an" should typically be interpreted to mean "at least one" or "one or more"); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to "at least one of A, B, and C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, and C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to "at least one of A, B, or C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, or C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B."

While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated in the description.

Referral Numerals:

Referral numeral Description
1 Fuel tank
2 Fuel cell module
3 Radiator
4 Heat exchanger
5 Generator
6 Condenser
7 Regenerative braking system
8 First circuit
9 Second circuit
10 Auxiliary devices
11 Pump
12 First valve
13 Second valve
14 Temperature controlled valve
14a First fluid path
14b Second fluid path
15 Power line
16 Control unit
100 Heat recovery system
200 Energy conversion unit