Battery charging device for inductive charging, in particular dynamic and / or stationary inductive charging, of a vehicle's traction battery

Description

[0001] The invention relates to a battery charging device for inductive charging, in particular dynamic and / or stationary inductive charging, of a traction battery of a vehicle that can be driven on a floor, in particular a ground-based industrial truck, with charging modules arranged next to one another that can be driven over by the vehicle, in each of which at least one primary coil is arranged, which can transmit electrical power to a secondary coil of the vehicle, so that the traction battery can be charged while the vehicle is driving over, wherein the charging modules can be placed on the floor and comprise at least one start module and at least one end module.

[0002] In industrial trucks, it is common practice and state of the art for traction batteries to either be removed from a battery compartment for charging during multi-shift operation and replaced with a fully charged traction battery, or for the driver to connect a charger to the traction battery via a plug connection towards the end of their shift to charge it during their break. This typically occurs at least once per shift, as the traction battery of a battery-electric industrial truck is usually designed so that a single charge of the traction battery can be used for an entire shift.

[0003] Furthermore, with lead-acid batteries, it is advisable to discharge them at least to a certain extent before recharging, since the technology of these batteries is not suitable for intermediate charging and, for example, undesirable memory effects can occur.

[0004] Thanks to newer technologies, batteries and accumulators can now be manufactured and used in industry that offer better performance data. Such batteries can be described as high-performance batteries, which are characterized by the fact that they have a higher energy density in relation to weight and / or volume than lead-acid accumulators and that they use a technology other than a lead-acid reaction for energy storage. Another feature of many high-performance batteries is that they can deliver high power during discharge and / or can be charged with high power. The typical energy densities in relation to weight and / or volume of a high-performance battery are above and outside the corresponding parameters for lead-acid batteries for at least one of the two values.

[0005] Lithium-ion batteries are increasingly being used as examples of such high-performance batteries. These batteries are characterized by high energy density and are subject to only a low memory effect, as well as allowing the battery to be discharged or charged with high power.

[0006] The use of such high-performance batteries is particularly advantageous in vehicles and, for example, in industrial trucks. Due to their high energy density relative to volume, a larger amount of electrical energy can be stored in the given space for the traction battery, thus increasing the range of a vehicle or the operating time of the industrial truck. In particular, it is possible to intermediately charge such high-performance batteries, especially lithium-ion batteries, and thus utilize short work breaks or other opportunities to recharge the traction battery. Intermediate charging also makes it possible to select a smaller capacity for the traction battery, thus saving costs.

[0007] For charging traction batteries of electric vehicles, it is known to use an inductive charging system. In this system, a charging unit is inductively coupled to a secondary coil of the vehicle via a primary coil and transfers electrical power, which is used, for example, to charge the traction battery of the electric vehicle. Optimal power transfer is possible when the primary coil and the secondary coil are aligned as parallel as possible and are as close together as possible. Charging can take place while the electric vehicle is stationary at a charging station, but also while driving, for example, when charging units with primary coils are embedded in the road surface.

[0008] A problem here is the flexible adaptation of the active and effective size of the primary coil. For example, it may be desirable to achieve a large cross-sectional area for the primary coil with a correspondingly equal cross-sectional area for the secondary coil in order to enable high power transmission. It is also advantageous to achieve the largest possible cross-sectional area for the primary coil if the cross-sectional area of ​​the secondary coil is significantly smaller in order to facilitate positioning. For example, shunting effort can be avoided if an industrial truck or electric vehicle is parked over a charging unit with a primary coil arranged in the roadway surface, as long as the entire cross-sectional area of ​​the secondary coil arranged in the floor area of ​​the industrial truck is covered due to the large cross-sectional area of ​​the primary coil.If charging is to take place while a vehicle is moving, a path must be covered with a primary coil as a charging station. It is desirable that this does not need to be activated all the time, so it is best to split the primary coil into several consecutive ones. The next primary coil must be activated in the direction of travel.

[0009] To flexibly adapt a charging station and the size and shape of the primary coil, it is known to use modules that combine a total area of ​​primary coils. This is disclosed, for example, in DE 10 2013 015 424 A1 for primary coils arranged in the floor.

[0010] DE 10 2016 119 677 A1 discloses a battery charging device for inductively charging a traction battery of an industrial truck, comprising a primary coil embedded in a floor area over which an industrial truck can travel. The primary coil is constructed from one or more modules arranged side by side, each with its own module coil. Each module can be configured for operation as a combined module or as a travel path module in relation to a specified adjacent module. When operated as a combined module, the module coil is operated synchronously with the adjacent module. When operated as a travel path module, the module coil is activated by the adjacent module when it detects an industrial truck. Conversely, the adjacent module is activated when the module itself detects an industrial truck.

[0011] Until now, the primary coils for dynamic inductive charging, i.e., inductive charging while driving, have been installed in the floor along with the additional power electronics. Installing primary coils under a layer of asphalt or concrete is a common practice. However, industrial trucks are predominantly used on industrial floors on company premises, especially in production halls. Such industrial floors, however, cannot be modified because the space is usually only rented by the operator. Floor modifications are accordingly expensive and generally not accepted by industrial customers.

[0012] Concrete modules that can be placed on the floor and into which the primary coil is installed have also been proposed. However, such concrete modules are only intended for stationary charging. Furthermore, the power electronics are located outside the concrete modules, creating an additional tripping hazard. Another problem is the width and height of the concrete modules. An autonomous industrial truck commonly used in intralogistics with a transport platform, also known as an ATP (Autonomous Transport Platform) or Turtle, Autonomous Mobile Robots (AMRs), or Warehouse Robots, could not charge inductively with such concrete modules because the ground clearance and wheelbase of such industrial trucks are too low.

[0013] From DE 10 2018 209 882 A1, a charging tunnel for inductive charging of a vehicle is known, which is formed from identical tunnel segments.

[0014] JP 2015 179 704 A1 discloses an inductive charging device for an industrial truck, in which a primary coil is installed in a recess of an aluminum ramp plate and the ramp plate is provided with a ramp at the front end and at the rear end.

[0015] EP 3 000 934 A1 discloses a road surface having a recess into which an inductive charging device is recessed. GB 2 522 852 A discloses a battery charging device for inductive charging comprising a single drive-over and lay-on charging module with a primary coil and first and second ramps at the front and rear ends. WO 2011 / 043628 A2 discloses a battery charging device for inductive charging comprising drive-over and ground-integrated charging modules, each charging module having a primary coil.

[0016] The present invention is based on the object of providing a battery charging device of the type mentioned above which enables inductive charging of the traction battery while driving, even in vehicles with low ground clearance, without structural changes to the ground.

[0017] This object is achieved according to the invention in that the at least one initial module and the at least one end module each have a ramp via which the vehicle can drive up and down from the ground onto the loading modules.

[0018] The invention is based on a modular structure of primary coils for inductively charging the traction battery of a vehicle, for example, an industrial truck, while in motion. The modular structure consists of at least one start module and one end module. The start and end modules are each provided with a ramp, whereby the ramps are designed such that the vehicles, in particular autonomous industrial trucks with a transport platform, for example, an ATP (Autonomous Transport Platform) or also called a Turtle, Autonomous Mobile Robots (AMRs), or Warehouse Robots, can drive onto and off the charging modules.

[0019] For example, the charging modules can be easily installed on a conventional industrial floor without any structural changes to the floor itself being necessary.

[0020] According to a particularly preferred embodiment of the invention, the charging modules are made of concrete, in particular polymer concrete or plastic variants, with the primary coil embedded in the concrete. All magnetizable materials are suitable for the charging modules, for example, normal concrete, polymer concrete, or plastic variants. Various carrier materials can also be added to these magnetizable materials as magnetizable particles, for example, granite pieces, in order to achieve better power transmission. Such magnetizable concrete, i.e., concrete to which magnetizable particles have been added, has the same static properties as any other concrete. The vehicle can thus travel without problems on the track formed by the charging modules.However, by embedding the primary coil in the concrete, a magnetizable component is created so that electrical power can be transferred contactlessly from the primary coil of the component to the secondary coil of the vehicle in order to charge the vehicle's traction battery.

[0021] Advantageously, each charging module contains its own power electronics. The charging modules thus each have a primary coil and power electronics for operating the primary coil. This allows each charging module to operate independently. Furthermore, this eliminates the need for connecting cables to external power electronics, thus preventing potential tripping hazards.

[0022] A preferred development of the invention provides that the charging modules have track guides for the vehicle in order to enable a particularly safe travel of the vehicle on the charging modules.

[0023] In a suitable embodiment of the invention, the track guides are designed as recesses in the surface of the charging modules. For this purpose, for example, track grooves can be incorporated into the surface of the charging modules as recesses for the wheels of the vehicles traveling on the charging modules.

[0024] Rail guides can also be used as track guides. For this purpose, rails can be embedded in the surface of the charging modules. The rails can also be attached to the surface of the charging modules, similar to railway tracks.

[0025] The track guides can comprise one or two parallel recesses or rails, or several parallel recesses or rails. In a design with two recesses or rails, for example, small autonomous transport platforms (ATPs) can use both recesses or rails, while forklifts with a wider track width use only one recess or rail and drive over the other recess or rail.

[0026] In a particularly advantageous embodiment of the invention, the charging modules have mechanical plug connections via which the charging modules arranged next to one another can be mechanically connected to one another, for example in a form-fitting manner, in such a way that the vehicle can drive over between the charging modules arranged next to one another.

[0027] The charging modules also conveniently have power supply interfaces, via which the adjacent charging modules can be electrically connected to each other and connected to a power grid via at least one power line leading to at least one charging module. Thus, a central power line from the power grid to one of the charging modules is sufficient to supply power to the charging modules. All other charging modules can be supplied via the charging modules' power supply interfaces.

[0028] A further advantageous embodiment provides that the charging modules have data communication interfaces via which the charging modules arranged next to one another can communicate. Communication between the charging modules is important because they are switched on one after the other, depending on the current location of the vehicle. For example, the charging module can receive information from the neighboring charging module that a vehicle is approaching. It can then activate its own primary coil with a delay, or deliberately in advance. The latter minimizes latency times when providing the electrical charging power. The charging modules can thus be used to create paths that can be used to recharge the vehicle's traction battery while driving.

[0029] The data communication interface of the charging modules can be formed by data cables with appropriate connectors. This allows for easy and optimal data transmission between the charging modules.

[0030] In a practical embodiment, the power supply interfaces and / or the data communication interfaces are integrated into the mechanical connectors.

[0031] To facilitate handling of the charging modules, the charging modules preferably have transport devices for transporting them by an industrial truck. The transport devices can be designed as recesses for the forks of an industrial truck. This allows the charging modules to be easily transported to any location in a hall using an industrial truck, such as a forklift. This ensures flexible installation of the charging modules.

[0032] In a preferred embodiment of the invention, flexible installation of the charging modules is also facilitated by providing at least one intermediate module between the initial module and the end module. Thus, the initial module and the end module can be extended as required with additional intermediate modules to extend the vehicle's possible travel path on the charging modules.

[0033] The intermediate modules can include straight and / or curved and / or bridge-shaped intermediate modules. Straight intermediate modules can be used to extend the track in a straight direction. Curved intermediate modules can also be used to create curved tracks, allowing for the greatest possible adaptation to local conditions. Bridge-shaped intermediate modules can be used, for example, at intersections, to bridge and cross other tracks, especially for smaller vehicles.

[0034] By standardizing the charging modules, especially the intermediate modules, cost reductions can be achieved for larger quantities.

[0035] According to a further development of the invention, the charging modules are provided with weight sensors that can detect foreign objects on the charging modules. This prevents any potential fire hazard caused by foreign objects that could heat up during operation of the charging module's primary coil.

[0036] According to a further development of the invention, the charging modules are designed as single- or multi-lane charging modules and / or can be laid as single- or multi-lane charging modules. Thus, the charging modules according to the invention can be used to create single- or multi-lane routes for dynamic charging of vehicles, which also allow for use in oncoming traffic.

[0037] The invention offers a whole range of advantages: By embedding the primary coil and the power electronics in the charging modules, in particular by encasing them in concrete, for example normal concrete, polymer concrete, or plastic variants, these components are reliably protected from environmental influences. The modular design of the coil technology enables rapid contact. No intervention in the hall environment is necessary. The invention can be used flexibly in the space, for example within a production hall, and can be flexibly expanded. Furthermore, the charging modules can be relocated flexibly if the most frequently used route changes. Even small halls and squares can be used for the inductive charging of vehicle traction batteries. The charging modules can be designed as single-track or multi-track.be laid out in single or multi-lane format so that routes can be created for the dynamic inductive charging of vehicles that can also be used in oncoming traffic.

[0038] Further advantages and details of the invention are explained in more detail with reference to the exemplary embodiments shown in the schematic figures. Figure 1 shows a perspective view of the initial module and the end module of the battery charging device, Figure 2 shows a schematic diagram of the battery charging device with charging modules and a vehicle driving over them, Figure 3 shows a perspective view of rectilinearly shaped intermediate modules, Figure 4 shows a perspective view of a curved intermediate module and Figure 5 shows a perspective view of a bridge-like intermediate module.

[0039] In the Figure 1The initial module 1 and the final module 2 of the battery charging device according to the invention are shown. The initial module 1 has a ramp 3 and the final module 2 has a ramp 4. Via the ramps 3 and 4, the Figure 1 A vehicle not shown can drive onto the starting module 1 and drive off again from the end module 2.

[0040] The ramp gradients of ramps 3, 4 are designed so flat that industrial trucks with low ground clearance, for example autonomous industrial trucks with a transport platform (ATP or Turtle, Autonomous Mobile Robot or Warehouse Robot) can drive onto the start module 1 and drive off from the end module 2.

[0041] The start module 1 and the end module 2 can be connected to each other via the mechanical plug connections 5 directly or via, in the Figures 3 to 5The intermediate modules 18, 19, 25 shown are mechanically firmly connected. The initial module 1 and the end module 2 as well as the intermediate modules 18, 19, 25 form the charging modules 10 of the battery charging device.

[0042] The mechanical plug connections 5 of the charging modules 10 can be formed by corresponding pins 5a and pin receptacles 5b in the charging modules 10. The pins 5a and pin receptacles 5b can be of any shape, for example, round, triangular, or square.

[0043] In the illustrated embodiment, power supply interfaces 6 and / or data communication interfaces 7 are also integrated into the mechanical plug connections 5.

[0044] A primary coil 8 and power electronics 9 are arranged inside each charging module 10. If the charging modules 10 are made of concrete, the primary coil 8 and power electronics 9 are embedded in the concrete.

[0045] To facilitate transport, the loading modules 10 are provided with transport devices 22, designed as lateral recesses 21 in the form of entry pockets for the forks of an industrial truck. This allows the loading modules 10 to be easily transported to any location in a hall using an industrial truck, such as a forklift. This ensures flexible installation of the loading modules.

[0046] The Figure 2schematically shows a battery charging device with charging modules 10 and a vehicle 11 traveling on the charging modules 10, in particular designed as an industrial truck, for example an autonomously driving industrial truck with a transport platform (ATP or Turtle, Autonomous Mobile Robot or Warehouse Robot). The charging modules 10 are arranged next to one another in the direction of travel F of the vehicle 11. The charging modules 10 placed on the floor 12 each have a primary coil 8, while the vehicle 11, arranged on the underside, has a corresponding secondary coil 13 between a front axle 14 and a rear axle 15. Electrical energy is transferred inductively from the primary coil 8 to the secondary coil 13 of the vehicle 11 in order to charge the traction battery of the vehicle 11.

[0047] Since each of the charging modules 10 has its own primary coil 8, the traction battery of the vehicle 11 can also be charged via the charging modules 10 while the vehicle 11 is passing over.

[0048] The loading modules 10 comprise the initial module 1 and the end module 2 as well as at least one intermediate module 18. The initial module 1 and the end module 2 have the ramps 3 and 4, via which the vehicle 11 can drive up from the ground 12 onto the loading modules 10 and drive off again.

[0049] The width of the charging modules 10 is designed such that the vehicle 11 can drive on the charging modules 10 (initial module 1, intermediate module 18, end module 2) and thus on the primary coils 8.

[0050] The Figure 3shows a perspective view of rectilinear intermediate modules 18. The intermediate modules 18 can be connected to another intermediate module 18, 19, 25 or to the initial module 1 or the end module 2 via the mechanical connectors 5. Power supply interfaces 6 and / or data communication interfaces 7 are also integrated into the mechanical connectors 5. The rectilinear intermediate modules 18 can be used to extend the travel path in a straight direction.

[0051] The charging modules 10 also have track guides 20 to ensure safe travel of the vehicle 11 on the charging modules 10. In the Figure 3 the track guides 20 are formed by two parallel recesses in the surface of the loading modules 10.

[0052] The Figure 4shows a perspective view of a curved intermediate module 19. The intermediate module 19 can also be mechanically connected to an intermediate module 18, 19, 25 or to the start module 1 or the end module 2 via the mechanical plug connections 5. Power supply interfaces 6 and / or data communication interfaces 7 are also integrated into the mechanical plug connections 5. The curved intermediate modules 19 can also be used to create curved travel paths, enabling the greatest possible adaptation to local conditions.

[0053] The Figure 5shows a perspective view of a bridge-shaped intermediate module 25. The intermediate module 25 can also be mechanically connected to an intermediate module 18, 19, 25 or to the start module 1 or the end module 2 via the mechanical plug connections 5. Power supply interfaces 6 and / or data communication interfaces 7 are also integrated into the mechanical plug connections 5. With a bridge-shaped intermediate module 25, for example, another route can be bridged and crossed at an intersection point.

Claims

1. Battery charging device for inductive charging, in particular dynamic and / or stationary inductive charging, of a traction battery of a vehicle (11) that is able to be driven on the ground (12), in particular a ground-based industrial truck, comprising charging modules (10), which are arranged next to one another and are driven over by the vehicle (11), in each of which at least one primary coil (8) is arranged, which is able to transmit electrical power to a secondary coil (13) of the vehicle (11) such that the traction battery is able to be charged while the vehicle (11) is driving over, wherein the charging modules (10) are able to be placed on the ground (12) and comprise at least one initial module (1) and at least one end module (2), characterized in that the at least one initial module (1) and the at least one end module (2) each have a ramp (3, 4), by way of which the vehicle (11) is able to drive onto / off the charging modules (10) from / onto the ground (12).

2. Battery charging device according to Claim 1, characterized in that the charging modules (10) are produced from concrete, wherein the primary coil (8) is embedded in the concrete.

3. Battery charging device according to Claim 1 or 2, characterized in that each charging module (10) contains its own power electronics (9).

4. Battery charging device according to one of Claims 1 to 3, characterized in that the charging modules (10) have track guides (20) for the vehicle (11).

5. Battery charging device according to Claim 4, characterized in that the track guides (20) are in the form of recesses in the surface of the charging modules (10) .

6. Battery charging device according to Claim 4, characterized in that the track guides (20) are in the form of rails that are applied to the surface of the charging modules (10).

7. Battery charging device according to one of Claims 1 to 6, characterized in that the charging modules (10) have mechanical plug connections (5), by way of which the charging modules (10) that are arranged next to one another are able to be mechanically connected to one another in such a way that it is possible for the vehicle (11) to drive over between the charging modules (10) that are arranged next to one another.

8. Battery charging device according to one of Claims 1 to 7, characterized in that the charging modules (10) have power supply interfaces (6), by way of which the charging modules (10) that are arranged next to one another are able to be electrically connected to one another and able to be connected to a power grid via at least one power line routed to at least one charging module (10).

9. Battery charging device according to one of Claims 1 to 8, characterized in that the charging modules (10) have data communication interfaces (7), by way of which the charging modules (10) that are arranged next to one another are able to communicate.

10. Battery charging device according to Claim 7 and Claim 8 and / or Claim 9, characterized in that the power supply interfaces (6) and / or the data communication interfaces (7) are integrated into the mechanical plug connections (5).

11. Battery charging device according to one of Claims 1 to 10, characterized in that the charging modules (10) have transport apparatuses (22) for transporting the charging modules (10) by an industrial truck.

12. Battery charging device according to Claim 11, characterized in that the transport apparatuses (22) are in the form of recesses (21) for fork tines of an industrial truck.

13. Battery charging device according to one of Claims 1 to 12, characterized in that at least one intermediate module (18, 19, 25) is provided between the initial module (1) and the end module (2).

14. Battery charging device according to Claim 13, characterized in that a plurality of intermediate modules (18, 19, 25) are provided and the intermediate modules (18, 19, 25) comprise rectilinearly shaped and / or curved and / or bridge-shaped intermediate modules (18, 19, 25).

15. Battery charging device according to one of Claims 1 to 14, characterized in that the charging modules (10) have weight sensors that are able to detect foreign objects on the charging modules (10).

16. Battery charging device according to one of Claims 1 to 15, characterized in that the charging modules (10) are of single-track or multiple-track design and / or are able to be laid as a single track or multiple tracks.