FR3141386A1 - Long-range electric motor vehicle - Google Patents

Abstract

The present invention relates to an electric motor vehicle comprising: a platform structure (12) of a motor vehicle (10) having a front part (16) opposite a rear part (18) and an electric motor (20) installed in said front part , said structure (12) comprising a floor (22) and on the one hand a first housing (32) extending under said floor from said front part (16) towards said rear part (18), and on the other hand a second housing (34) extending from said first housing (32) towards said rear part (18); a storage battery (36) installed inside said first housing (32) and coupled to said electric motor (20). The vehicle includes a fuel cell (40) within said second housing (34) and coupled to said storage battery (36); and, a dihydrogen tank (42) installed in said rear part (18) to be able to supply said fuel cell (40). Figure to be published with the abstract: Fig. 1

Description

Long-range electric motor vehicle

The present invention relates to an electric motor vehicle and to a method of manufacturing such a vehicle.

Known electric motor vehicles include a platform structure extending from a front part to a rear part. The front part supports a powertrain including an electric motor, while the rear part outlines the contours of the vehicle's trunk.

Also, the structure includes a floor which extends from the front part to the rear part. Accumulator batteries are then housed under this floor to accumulate the electrical energy necessary for the operation of the electric motor.

Usually, a first housing which extends from the front part, under the floor to the right of row two of the vehicle, receives a first accumulator battery pack. Row two is the second row of seats in the vehicle after the driver and passenger.

In addition, a second housing located to the right of row two generally receives a second accumulator battery pack. This second housing can have a height greater than that of the first, taking into account the free space to the right of row two and therefore, it can receive a second accumulator battery block having a height greater than that of the first.

Thus, we take advantage of all the free space under the floor to equip the motor vehicle with a maximum quantity of accumulator batteries, so as not to compromise the habitability of the vehicle.

Indeed, autonomy is one of the major handicaps of electric motor vehicles and this is the reason why we are looking for the slightest free space to insert accumulator battery elements. Another handicap is the recharge time of accumulator batteries.

On the other hand, the significant weight of the batteries further burdens the energy balance of electric motor vehicles.

Also, a problem which arises and which the present invention aims to solve is to provide an electric motor vehicle whose autonomy is improved.

In order to solve this problem, it is proposed, according to a first object, an electric motor vehicle comprising: a motor vehicle platform structure having a front part opposite a rear part and an electric motor installed in said front part, said structure comprising a floor extending from said front part to said rear part, and on the one hand a first housing extending under said floor from said front part towards said rear part, and on the other hand a second housing extending from said first housing towards said rear part; a storage battery installed inside said first housing to be able to electrically couple said storage battery and said electric motor. The vehicle further comprises: a fuel cell installed inside said second housing to electrically couple said fuel cell and said storage battery; and, a dihydrogen tank installed in said rear part to be able to power said fuel cell.

Thus, a characteristic of the invention lies in the implementation of a fuel cell associated with its dihydrogen tank in a traditional electric automobile vehicle. Such an association is carried out in a motor vehicle platform structure already implemented for an electric motor vehicle powered by single accumulator batteries. Therefore, the dimensions and capacities of the storage batteries are significantly reduced to be able to install the fuel cell. In addition, the fuel cell used has a power significantly lower than that of fuel cells usually used in motor vehicles.

In this way, the total dimensions of the assembly allow the installation of accumulator batteries and the fuel cell associated with its tank on an electric motor vehicle platform already implemented.

Despite this reduction in energy from the two sources of electrical energy, the autonomy of the vehicle can be increased by more than 10% for example, and advantageously by more than 20%.

Furthermore, for a given long-distance journey, the electric motor vehicle in accordance with the invention makes it possible to significantly improve the average journey time, if we consider the need to make at least one stop to refuel. dihydrogen. Indeed, the hydrogen tank can be easily filled in a very short time compared to the recharge time of storage batteries, whatever the technology used.

In addition, by using an electric automobile vehicle platform structure already implemented, additional vehicle design costs are avoided.

Furthermore, it is easy, as will be explained in more detail later in the description, to produce on the same assembly line, both mixed electric motor vehicles including storage batteries and a fuel cell. and electric motor vehicles equipped only with storage batteries. In which case, the aforementioned second housing can accommodate additional battery elements. And we then dispense with the installation of a dihydrogen tank.

In addition, the orderly implementation of the storage battery, adjacent to the electric motor, and the fuel cell then the hydrogen tank allows the transfer of energy from the rear to the front without significant loss. In fact, the hydrogen tank supplies the fuel cell which itself is coupled to the storage battery, which supplies the electric motor. In addition, contiguous elements in a chain require shorter cables and conduits.

According to a particularly advantageous embodiment of the invention, the vehicle further comprises a direct current converter installed inside said second housing to couple said fuel cell and said storage battery. Indeed, the electric motor of the vehicle requires a voltage supply of around 400 V for example, and the fuel cell produces a voltage close to 80 V. Consequently, a voltage converter is associated with the fuel cell. combustible, in the second housing.

Furthermore, and according to an advantageous implementation characteristic, the vehicle according to the invention comprises a first cooling circuit of said accumulator battery and a second cooling circuit of said fuel cell. Indeed, the optimal operating temperature of a fuel cell is not equal to the operating temperature of a storage battery. Therefore, two differently regulated cooling circuits are necessary.

It will be observed that in certain circumstances, particularly for storage batteries in cold periods, a supply of calories is necessary.

Furthermore, the vehicle preferably comprises a third cooling circuit of said converter coupled to said first cooling circuit. Indeed, the optimal operating temperature of the converter is close to the optimal operating temperature of the storage battery and consequently, the third circuit can be coupled to the first circuit without difficulty, in particular to evacuate thermal energy. In this way, the length of the conduits is also minimized.

In addition, the vehicle advantageously comprises a heat exchanger installed in said front part and coupled to the first and second cooling circuits. Such a heat exchanger, located at the front of the vehicle, makes it possible to more easily evacuate thermal energy when the vehicle is rolling. Furthermore, the first circuit is connected differently to the exchanger compared to the second circuit, so as to be able to evacuate thermal energy produced by the storage batteries and by the fuel cell differently.

Also, we will observe that, unlike the electrical energy produced which travels from the rear to the front, the cooling of the storage battery and the fuel cell most often takes place from the front. rearward. In this way, the cooling flows are optimized.

It will also be observed that the first cooling circuit also allows the thermal energy produced by the electric motor to be evacuated.

According to a first alternative embodiment of the invention, said first housing and said second housing are independent of each other. They are, however, joined to each other so as to be able to electrically connect the fuel cell and the storage battery with the shortest possible connection means.

Also, the motor vehicle comprises: a first box defining said first housing and a second box defining said second housing; and, a first cover and a second cover for closing said first and second boxes respectively. The first and second boxes have a bottom wall applied against the floor, and an opposite opening. Also, to preserve the storage battery and the fuel cell, the boxes are closed from below using a cover. These covers can be dismantled independently of each other so that the storage battery or the fuel cell can be accessed independently.

According to a second alternative embodiment of the invention, said first housing and said second housing together form a single housing adapted to accommodate said accumulator battery and said fuel cell.

Therefore, the vehicle has a single box having the same bottom wall and making it possible to accommodate the accumulator battery and the fuel cell attached to each other. On the other hand, the single box can accommodate two covers joining together, one facing the single storage battery, the other facing the single fuel cell and the converter.

Furthermore, said dihydrogen tank is installed in said rear part, preferably, under said floor. The floor extending into the rear part of the vehicle, it thus delimits the trunk of the vehicle. Therefore, the tank is installed under the trunk of the vehicle. Taking into account the capacities of the fuel cell, for example between 10 kW and 15 kW, a power lower than that of fuel cells usually used in motor vehicles with this sole source of energy, the dihydrogen tank is of smaller volume . For example, its external volume is less than 100 l, and it contains 2.5 kg of dihydrogen under a pressure of 700 bars.

It will be observed that the storage battery delivers a quantity of energy of, for example, between 40 and 45 kWh.

According to another object, a method of manufacturing an electric motor vehicle is proposed comprising the following steps: a motor vehicle platform structure is provided having a front part opposite a rear part and an electric motor installed in said front part , said structure comprising a floor extending from said front part to said rear part and, on the one hand a first housing extending under said floor from said front part towards said rear part and, on the other hand a second housing extending from said first housing towards said rear part; a storage battery is provided and said storage battery is installed inside said first housing to be able to electrically couple said storage battery and said electric motor. And a fuel cell and a dihydrogen tank are further provided, and said fuel cell is installed inside said second housing to electrically couple said fuel cell to said storage battery, while said tank is installed of dihydrogen in said rear part to be able to power said fuel cell.

Thus, another advantage of the invention lies in the possibility of manufacturing an electric motor vehicle according to the invention, on a manufacturing line initially dedicated to the electric motor vehicle equipped with only the accumulator battery. To do this, a motor vehicle platform structure is implemented similar to that of vehicles equipped with batteries only, and the second housing is intended to receive the fuel cell, while a particular arrangement of the rear part is provided. to accommodate the hydrogen tank.

Furthermore, the fixing elements remain identical for both types of platform.

In addition, it is possible to manufacture two types of vehicle on the same production line, one where the vehicles are equipped with a battery and a fuel cell, the other where the vehicles are equipped only with a battery, the second housing then including an additional accumulator battery element.

Such a method thus makes it possible to reduce the production costs of these vehicles additionally equipped with a fuel cell.

Other particularities and advantages of the invention will emerge on reading the description given below of particular embodiments of the invention, given for information but not limitation, with reference to the appended drawings in which:

is a schematic side view showing an electric motor vehicle according to the invention;

is a schematic bottom view of the electric motor vehicle according to the invention;

is a schematic bottom view of the electric motor vehicle according to the invention in accordance with a first variant of execution;

is a partial schematic bottom view of the electric motor vehicle according to the invention in accordance with a second alternative embodiment;

is a detailed schematic view of the invention in accordance with the second variant of execution shown on the ; And,

is a detailed schematic view of the invention in accordance with the second variant of execution shown on the .

There shows, from the side and schematically, the contours of an electric motor vehicle 10 equipped with equipment according to the invention.

Also the vehicle fits into an orthogonal reference X, Y, Z, in which the axis the Y axis extends in a transverse direction of the vehicle, oriented from left to right; and the Z axis extends in a vertical direction, oriented away from the ground.

Thus, the motor vehicle 10 comprises a platform structure 12 on which a bodywork 14 is installed. This platform structure 12 is usually used for the manufacture of traditional electric motor vehicles.

Also, the platform structure 12 has a front part 16 opposite a rear part 18. The front part 16 is equipped with a powertrain including an electric motor 20.

In addition, the platform structure 12 has a floor 22 which extends from the front part 16, into the rear part 18. The floor 22 delimits in particular, a passenger compartment 24 of a base 26.

In the passenger compartment 24, there is a row of front seats 28 and a row of rear seats 30 extending, by definition, to the rear of the front seats 28. And we designate “row one” the space defined by the front row of seats 28 and “row two” the space defined by the rear row of seats 30.

Furthermore, at the rear of row two, to the right of the rear part 18, is located a trunk 31 of the motor vehicle 10.

In addition, the platform structure 12 has a first housing 32 located under the central part of the floor 22, to the right of row one and a second housing 34 located to the right of row two 30, behind the first housing 32.

It will be observed that the height of the second housing 34 is significantly greater than the height of the first housing 32. On the other hand, the first housing 32 extends in the longitudinal direction -X, towards the front part 16, over a length much greater than that over which the second housing 34 extends. For example, the first housing 32 extends over a length more than three times greater than that of the second housing 34.

Thus, the first housing 32 receives a battery of accumulators 36 which extends throughout the free space defined by the first housing 32. The battery of accumulators 36 is then electrically coupled to the motor 20 of the powertrain by means of a first electrical connection 38.

The storage battery 36 has a storage capacity of between 40 kWh and 45 kWh for example. It restores this energy at a voltage of 400 V. This storage capacity is significantly lower than that of storage batteries usually used in electric vehicles, which is generally between 45 kWh and 60 kWh.

The second housing 34, generally used to receive complementary elements of the accumulator battery, here receives, in accordance with the invention, a fuel cell 40.

The fuel cell 40 is then electrically coupled to the storage battery 36. The fuel cell has a power of between 10 kW and 15 kW for example and preferably 13 kW.

In addition, the fuel cell 40 is supplied with dihydrogen thanks to a tank 42 of generally cylindrical shape installed in the rear part 18 of the platform 12, under the floor of the trunk 31. The tank 42 has an external volume substantially less than 100 l, for example 95 l. And it can store a volume of hydrogen greater than 2.5 kg and at a pressure of 700 bars.

We find on the , the motor vehicle 10 seen from below. There we find, from the front part 16 towards the rear part 18, the electric motor 20 of the powertrain, the storage battery 36, the fuel cell 40 and the hydrogen tank 42.

It will be observed that the accumulator battery 36 extends transversely in the direction Y over the entire width of the motor vehicle 10. On the other hand, the fuel cell 40 extends over a smaller width taking into account the space available at the level of rank two.

Furthermore, the fuel cell 40 is equipped with a DC/DC direct current converter 44 making it possible to convert the electrical energy produced by the fuel cell 40 at a voltage close to 80 V, to a voltage of 400 V.

We will refer to the illustrating, seen from below and according to a first variant of execution, where the fuel cell 40 is independent of the accumulator battery 36, the energy transfer circuits inside the vehicle 10.

Thus, we find from the front part 16, towards the rear part 18, the electric motor 20, the storage battery 36, the fuel cell 40 and the hydrogen tank 42.

It will be observed that the rear part 18 of the platform structure 12 has two substantially parallel rear spars 43, 45 and that the dihydrogen tank 42 extends transversely between the two spars 43, 43. Its external diameter is less than 500 mm and it extends under the trunk floor specifically designed for this purpose. In this way, the tank 42 is preserved in the event of an impact.

In addition, the motor vehicle 10 is equipped, at the front, with a heat exchanger 46, commonly called: “radiator”. It makes it possible to evacuate the thermal energy released by the different elements of the vehicle 10.

First of all, the dihydrogen tank 42 has a filling conduit 48 opening outside the vehicle 10. The tank 42 is connected to the fuel cell 40 by a supply conduit 50.

In addition, the fuel cell 40 is electrically coupled to the storage battery 36 by means of two first electrical coupling cables 52, 54. The fuel cell 40 and the storage battery 36 being contiguous, these first two cables electrical coupling 52, 54 are relatively short.

The accumulator battery 36 is itself coupled to the electric motor 20 by the electrical connection 38 made of two second electrical coupling cables 56, 58, themselves relatively short taking into account the proximity of the electric motor and the battery accumulators 36.

In addition, the accumulator battery 36 has a charging cable 60 opening to the outside.

The motor vehicle 10 also includes a cooling system for the engine 20, the storage battery 36, the fuel cell 40 and the converter 44.

Thus, from the front part 16, towards the rear part 18, and from the heat exchanger 46, two first circuits 62, 64 extend in a serpentine manner, one against the accumulator battery 36, the other against the converter 44. These first two circuits 62, 64 are substantially at the same temperature. And a second circuit 66 extends from the heat exchanger 46 to the fuel cell 40.

Also, according to this first variant of execution, the first housing 32 accommodates the accumulator battery 36, which is reduced by several electrical elements compared to that which is implemented in usual electric vehicles. On the other hand, the second housing 34 is adapted to receive the fuel cell 40.

The two accommodations are independent and are defined by two boxes not shown here. These boxes are adapted to take into account electrical cables and the circulation of fluids. These boxes are suitable for receiving protective covers.

Furthermore, the fixing points of the platform structure 12 are reused for the installation of the two boxes.

We will now describe with reference to the - , another variant of execution in which the two aforementioned boxes become one. Also, the elements of this execution variant presenting the same functions as the elements of the previous execution variant will carry an identical reference accompanied by a prime sign: "'".

We thus find on the , the motor vehicle 10', where the first two circuits only form a single first circuit 62' extending in a serpentine manner in the two housings 32', 34'. The second circuit 66' extends directly from the heat exchanger 46' to the second housing 34' and opposite the fuel cell 40', just as in the first variant.

Thus, the accumulator battery 46' can be attached to the fuel cell 40'.

There shows in detail a first box 70 defining the first housing 32' and a second box 72 closed by a second cover 74, defining the second housing 34' and inside which extends the fuel cell 40' associated with the converter 44'. In this way, we understand that the second box 72 is closed in a sealed manner in order to preserve the fuel cell 40' and the converter 44'. The second cover 74 is perfectly removable so as to facilitate assembly during manufacture of the vehicle or maintenance in after-sales service.

Also, the shows the same object as that of the , with the difference that the first box 70 is closed by a first cover 76. In this way, the accumulator battery 36' is preserved from the outside. In addition, the first cover 76 is perfectly removable.

The invention also relates to a method of manufacturing an electric automobile vehicle as described above through a production line on which traditional electric automobile vehicles powered exclusively with storage batteries are also produced.

Thus, according to the method, we provide a motor vehicle platform structure similar to that which is implemented for the manufacture of usual electric vehicles without a fuel cell. The platform has a front part opposite a rear part and an electric motor installed in the front part. It has a floor extending from the front part to the rear part. Also, the platform includes a first housing extending under the floor from the front part towards the rear part and a second housing extending from the first housing towards the rear part. According to the method, a storage battery is provided and installed inside the first housing to be able to electrically couple it to the electric motor. Also, a fuel cell and a dihydrogen tank are provided, and the fuel cell is installed inside the second housing to electrically couple it to the storage battery, while the dihydrogen tank is installed in the second housing. rear part to be able to power the fuel cell.

Claims (10)

Electric motor vehicle comprising:
- a platform structure (12) of a motor vehicle (10) having a front part (16) opposite a rear part (18) and an electric motor (20) installed in said front part, said structure (12) comprising a floor (22) extending from said front part (16) to said rear part (18), and on the one hand a first housing (32) extending under said floor from said front part (16) towards said part rear (18), and on the other hand a second housing (34) extending from said first housing (32) towards said rear part (18);
- an accumulator battery (36) installed inside said first housing (32) to be able to electrically couple said accumulator battery and said electric motor (20);
characterized in that it further comprises:
- a fuel cell (40) installed inside said second housing (34) to electrically couple said fuel cell (40) and said storage battery (36); And,
- a dihydrogen tank (42) installed in said rear part (18) to be able to supply said fuel cell (40). Electric motor vehicle according to claim 1, characterized in that it further comprises a direct current converter (44) installed inside said second housing (34) to couple said fuel cell (20) and said battery. accumulators (36). Electric motor vehicle according to claim 1 or 2, characterized in that it comprises a first cooling circuit (62, 64) of said accumulator battery and a second cooling circuit (66) of said fuel cell (40) . Electric motor vehicle according to claims 2 and 3, characterized in that it comprises a third cooling circuit of said converter (44) coupled to said first cooling circuit (62, 64). Electric motor vehicle according to claim 3 or 4, characterized in that it comprises a heat exchanger (46) installed in said front part (16) and coupled to the first and second cooling circuits (62, 64, 66). Electric motor vehicle according to any one of claims 1 to 5, characterized in that said first housing (32) and said second housing (34) are independent of each other. Electric motor vehicle according to any one of claims 1 to 6, characterized in that it comprises:
- a first box (70) defining said first housing (32) and a second box (72) defining said second housing (34); And,
- a first cover (74) and a second cover (76) for respectively closing said first (70) and second (72) boxes. Electric motor vehicle according to any one of claims 1 to 5, characterized in that said first housing (32) and said second housing (34) together form a single housing adapted to accommodate said accumulator battery and said battery. combustible. Electric motor vehicle according to any one of claims 1 to 6, characterized in that said dihydrogen tank (42) is installed in said rear part (18) under said floor (22). Method of manufacturing an electric motor vehicle comprising the following steps:
- a motor vehicle platform structure (12) is provided having a front part (16) opposite a rear part (18) and an electric motor (20) installed in said front part, said structure (12) comprising a floor ( 22) extending from said front part to said rear part and, on the one hand a first housing (32) extending under said floor (22) from said front part towards said rear part and, on the other hand a second housing (34) extending from said first housing towards said rear part;
- a storage battery (36) is provided and said storage battery is installed inside said first housing (32) to be able to electrically couple said storage battery (36) and said electric motor (20);
characterized in that a fuel cell (40) and a dihydrogen tank (42) are further provided, and said fuel cell (42) is installed inside said second housing (36) to electrically coupling said fuel cell (42) to said storage battery (36), while installing said dihydrogen tank (42) in said rear part (18) to be able to power said fuel cell (40).