Wireless system having a multilayer capacitor, and method for producing same

Abstract

The invention relates to a wireless system (100) having a first assembly (20) comprising a power consumption coil (21) and at least one capacitor (10), which form a power consumption resonant circuit, and having a second assembly (30) for receiving an electrical alternating current and generating an electrical direct current and / or for receiving an electrical direct current and generating an electrical alternating current, wherein the capacitor (10) is in the form of a multilayer capacitor with a capacitor body (11) having first electrode layers (1) and second electrode layers (2) which alternate along a stacking direction of the capacitor (10) with dielectric layers (3) inserted therebetween, each of the first electrode layers (1) having at least one first internal electrode (1a), and each of the second electrode layers (2) having at least one second internal electrode (2a). The capacitor (10) further comprises a first coil connection (12a), a second coil connection (12b), a first capacitor connection (13a), and a second capacitor connection (13b), the first internal electrodes (1a) being connected to the first coil connection (12a), and the second internal electrodes (2a) being connected to the second coil connection (12b). The second assembly (30) is electrically conductively connected to the capacitor (10) via the first capacitor connection (13a) and the second capacitor connection (13b), and one of the first electrode layers (1), one of the second electrode layers (2), or a dielectric bottom layer (4) is formed by a support (5) on which the capacitor (10) is mounted.

Description

[0001] WIRELESS SYSTEM WITH MULTI-LAYER CAPER AND METHOD FOR ITS MANUFACTURING

[0002] The present invention relates to the field of wireless systems for transmitting electrical energy to and / or from vehicles, and in particular to a multilayer capacitor as part of a resonant circuit of such charging systems. The present invention further relates to a method for manufacturing such a wireless system comprising a multilayer capacitor with a set total capacitance.

[0003] Electric vehicle batteries can be charged with alternating current (AC) or direct current (DC). Typical AC chargers can provide a charging power of up to 22 kW. AC charging systems can be divided into wired and wireless charging systems, with wireless charging systems primarily implemented as inductive charging systems (ICS). An ICS typically consists of two separate modules, often referred to as the ground pad module (GPM) and the car pad module (CPM). The GPM is installed outside the electric vehicle, while the CPM is mounted inside the vehicle, usually on the underside.The CPM can receive the oscillating electromagnetic, primarily magnetic, field from the GPM, convert it into an alternating current, further convert it (typically rectify it), and generate a charging current (typically direct current) used to charge a vehicle's traction battery. Wireless charging systems are often more convenient for the user, as no manual intervention is usually required to start the battery charging process, other than placing the vehicle over the GPM. In such wireless charging systems, several resonant circuits handle a large amount of reactive power compared to the active power. These resonant circuits include large coils or inductors and capacitors, which ensure temperature and voltage stability as well as a long service life for the charging systems.The stability of the capacitance value is crucial for keeping the resonant frequency within the design parameters and ensuring efficient energy transfer. For example, the resonant chamber of modern wireless charging systems generates 150 kVA of reactive power for a 10 kW output. Due to manufacturing tolerances in various components of these wireless charging systems, precise capacitors are essential for tuning.

[0004] Multilayer capacitors with a multilayer structure are known, for example, from US patent 2,389,420 and have a structure consisting of a multitude of nested and offset layers of an electrically conductive metal film and electrically insulating layers, for example of a ceramic oxide.

[0005] These types of multilayer ceramic capacitors (MLCCs) are generally manufactured by coating and alternately laminating layers of dielectric ceramic material, known as green layers, with films of a conductive paste. The laminated dielectric layers and conductive paste films are then baked, i.e., sintered, at temperatures ranging from 1300 °C to 1600 °C. During firing, the dielectric ceramic layers become dielectric, and the conductive paste forms internal electrodes.

[0006] Due to the ongoing compaction and miniaturization of electronic circuits, there is also a trend towards reducing the size and increasing the capacitance of ceramic multilayer capacitors. Several methods for manufacturing compact ceramic multilayer capacitors exist for reducing the thickness of the dielectric layers and increasing the number of layers to be laminated. However, these methods are complex and result in high costs for small ceramic multilayer capacitors with high energy density. Furthermore, small surface-mountable ceramic multilayer capacitors are very sensitive to mechanical stresses during assembly and to mechanical deflection of the printed circuit board due to vibration and shock.Even relatively low mechanical bending loads and especially torsional loads on the components can very quickly lead to cracking and fractures in the ceramic, which can result in a short circuit of the component.

[0007] There are applications that place high demands on the tolerance limits of capacitors, particularly regarding capacitance. With the state-of-the-art manufacturing processes for ceramic multilayer capacitors, it is difficult to obtain capacitors with the necessary tolerance accuracy on a repeatable basis. This is because the capacitance depends to a large extent on factors such as the thickness of the green layers, the process parameters used, and the composition and particle size of the ceramic granules in a given batch being processed. Not least because of the aforementioned difficulties, currently commercially available ceramic multilayer capacitors characterized by a defined capacitance and high tolerance accuracy are relatively expensive.

[0008] It is an object of the present invention to provide a ceramic capacitor in which the disadvantages of the prior art described above are at least mitigated and which is characterized in particular by increased mechanical stability, higher voltage and temperature stability, a defined capacitance value with low tolerance, and lower unit costs. It is further an object of the present invention to provide a method by which such ceramic capacitors can be manufactured simply and cost-effectively.

[0009] The problem is solved by a ceramic capacitor and a method for manufacturing a ceramic capacitor comprising the features of the independent claims. The dependent claims, the description, and the figures describe further developments and particular embodiments of the invention.

[0010] The wireless system for transmitting electrical energy to and / or from a vehicle according to an embodiment of the present invention comprises a first assembly that performs at least one of the following two functions:

[0011] - Recording an oscillating electromagnetic field and generating an alternating electric current;

[0012] - Receiving an alternating electric current and generating an oscillating electromagnetic field;

[0013] The wireless system also includes a second assembly that performs at least one of the following two functions:

[0014] - Receiving an alternating electric current and generating a direct electric current;

[0015] - Receiving a direct current and generating an alternating current;

[0016] The first assembly comprises a power-inducting coil and at least one capacitor, which together form a power-inducting resonant circuit. The capacitor is designed as a multilayer capacitor with a capacitor body comprising first electrode layers and second electrode layers, which are arranged alternately with interspersed dielectric layers along a stacking direction of the capacitor. The stacking direction is the direction in which the electrode layers and the dielectric layers are stacked. The first electrode layers each have at least one first internal electrode. The second electrode layers each have at least one second internal electrode. The capacitor further comprises a first coil terminal, a second coil terminal, a first capacitor terminal, and a second capacitor terminal.The first internal electrodes are connected to the first coil terminal, and the second internal electrodes are connected to the second coil terminal. The second assembly is electrically connected to the capacitor via the first and second capacitor terminals. One of the first electrode layers, one of the second electrode layers, or a dielectric base layer is formed by a support on which the capacitor is mounted.

[0017] The first assembly may in particular be a magnetic assembly.

[0018] The second assembly may, in particular, be an electronic assembly.

[0019] In a receiving operation, the first assembly serves to receive the oscillating electromagnetic field and to generate the alternating current, and the second assembly serves to receive the alternating current and to generate the direct current.

[0020] In a transmitting operation, the first assembly serves to receive the alternating electric current and to generate the oscillating electromagnetic field, and the second assembly serves to receive the direct electric current and to generate the alternating electric current.

[0021] A GPM can be configured for unidirectional operation, i.e., for one-way power transmission to the vehicle, and is therefore intended only for transmitting. A CPM can be configured for unidirectional operation, and is therefore intended only for receiving. A GPM or a CPM can be configured for bidirectional operation, and is therefore used for both transmitting and receiving.

[0022] A wireless system according to the invention is characterized by the fact that a relatively large capacitance can be integrated across multiple layers into a substrate of the first assembly. Compared to the capacitors used in prior art wireless systems of the same type, such a capacitor is characterized by a lower energy density, which reduces the cooling power required for the capacitor and thus increases its lifespan and, consequently, the functionality of the wireless system. Furthermore, such a capacitor can be integrated flexibly and in a space-saving manner into the first assembly and can be manufactured relatively easily with a defined total capacitance. This eliminates the need for a multitude of previously available, expensive resonant capacitors with precisely defined but small capacitances.Replacing several small and expensive resonant capacitors with a relatively large ceramic capacitor integrated into a carrier also offers the advantage of reduced assembly effort due to fewer solder joints, thus reducing production costs and time. The smaller number of components also means fewer potential sources of failure, which increases the reliability and lifespan of a wireless system incorporating such a ceramic capacitor.

[0023] In various embodiments, the first coil terminal is configured as the first via and the second coil terminal as the second via. Both the first and second vias extend within the capacitor body. Specifically, the first and second vias can extend along the stacking direction of the capacitor.

[0024] Through-hole vias are particularly easy and cost-effective to manufacture, for example, through simple drilling, and are characterized by high mechanical strength and thus reliability. This minimizes the risk of the electrical contact to the internal electrodes of the electrode layers breaking down due to vibrations or mechanical stress. Especially at high frequencies, through-hole vias result in lower losses. Compared to surface-mount connections, through-hole vias allow for better utilization of available space. Furthermore, heat dissipation can be improved through through-holes, as heat can be more efficiently transferred away from the capacitor body through the contact, which is particularly important in applications requiring high power density.The aforementioned advantages apply particularly to vias extending in the stacking direction of the capacitor.

[0025] In various embodiments, the first via extends through the capacitor body without touching the second internal electrodes. The second via extends through the capacitor body without touching the first internal electrodes.

[0026] In various configurations, the first assembly comprises a housing in which at least one capacitor is located. The power-conducting coil is located outside the housing. The first and second coil connections pass through the housing. This allows for a particularly easy connection between the coil and the capacitor during installation, repair, and maintenance.

[0027] In its various forms, the power-consumption resonant circuit comprises exactly one capacitor, which provides a total capacitance comprised of multiple capacitors. These capacitors are connected in series and / or parallel. This allows for a higher total capacitance than would be possible with a single capacitor. Multiple capacitors connected in series or parallel can increase the voltage rating, improving the overall reliability of the capacitor under high-voltage conditions. Distributing the total capacitance across multiple capacitors allows for more even heat dissipation and reduces the risk of thermal hotspots. Even if one capacitor fails, the total capacitance of the capacitor can often still be maintained, further increasing the reliability of the overall system.Furthermore, combining different capacitance components makes it easier to meet specific requirements for capacitance, voltage, and frequency response. In other words, it achieves greater flexibility in circuit design.

[0028] In various embodiments, the capacitor comprises two series and one parallel capacitance component. The first electrode layer includes the first internal electrode and a third internal electrode, which is electrically isolated from the first internal electrode. The second electrode layer includes the second internal electrode and a fourth internal electrode, which is electrically isolated from the second internal electrode. The dielectric layer arranged between the first and second electrode layers electrically isolates the first and fourth internal electrodes, as well as the second and third internal electrodes, from each other.Thus, a first capacitance component is formed by the first internal electrode and the fourth internal electrode, a second capacitance component is formed by the second internal electrode and the third internal electrode, and a third capacitance component is formed by the third internal electrode and the fourth internal electrode.

[0029] Such a circuit, consisting of two capacitors in series and one in parallel, allows for very precise adjustment of the total capacitance. The series connection increases the voltage rating compared to a single capacitor. The parallel capacitor increases the reliability and fault tolerance of the circuit. In various embodiments, the capacitor body has a width of at least 20 mm, preferably 30 mm to 100 mm, measured perpendicular to the stacking direction. The length of the capacitor body, measured perpendicular to the stacking direction, is at least 30 mm, preferably 40 mm to 150 mm. The thickness of the capacitor body, measured in the stacking direction, is 0.05 mm to 5 mm. A capacitor body with the aforementioned dimensions achieves a balance between the capacitor's total capacitance and its space requirements.

[0030] In its various forms, the carrier is a housing for the wireless system. Specifically, the carrier can be a housing for the first assembly. The housing forms one of the first or one of the second electrode layers, enabling a particularly space-saving and cost-effective integration of a capacitor with a comparatively high capacitance into the wireless system.

[0031] In various embodiments, the dielectric layers each comprise a ceramic. Preferably, the dielectric layers each consist essentially of a ceramic. This allows the dielectric layers to be produced simply and with a high degree of design freedom.

[0032] In various configurations, the first and second internal electrodes are connected or connectable to the power-sensing coil via the first and second coil terminals, respectively. This allows the power-sensing coil to be more easily disconnected from the capacitor when necessary, for example, during maintenance or repair work.

[0033] In various configurations, at least one of the first internal electrodes and the second internal electrode are selected from a material belonging to the group consisting of aluminum, nickel, copper, graphite, and carbon. Aluminum electrodes are characterized by their generally good availability, low cost, and good electrical conductivity. Nickel is characterized by good electrical conductivity and good corrosion resistance. Copper is characterized by good electrical conductivity and particularly good thermal conductivity. Graphite and carbon offer a particularly large surface area for a particularly high capacity.

[0034] In some embodiments, the first and second vias each extend through the substrate to a side of the substrate facing away from the capacitor. This allows for a particularly convenient connection between the coil and the capacitor.

[0035] In some embodiments, the first internal electrodes each have a recess that electrically isolates the second via from the first internal electrodes. Similarly, the second internal electrodes each have a recess that electrically isolates the first via from the second internal electrodes. Such recesses make it easy for the capacitor body to have a plurality of capacitance components connected in series and / or parallel.

[0036] In embodiments, the first and second vias each have a circular cross-section. In particular, the cross-section of the first and second vias can range from 2 mm to 50 mm, preferably from 15 mm to 35 mm, and more preferably from approximately 25 mm. Within this range, a balance is achieved between properties such as electrical resistance, current-carrying capacity, mechanical stability, and thermal conductivity on the one hand, and weight and material costs on the other.

[0037] In some embodiments, the first and / or second coil terminal is selected from the group consisting of a flat piece, a wire, and a stranded wire. Compared to a round wire of the same thickness, a flat piece has a larger cross-sectional area, which reduces electrical resistance, leads to lower power losses, and improves heat dissipation and efficiency. Wires are generally easier and less expensive to obtain in various diameters and materials and are more flexible than rigid flat pieces. The use of a stranded wire allows the coil and coil terminals to be provided from a single component, which has a positive impact on the complexity of the wireless system.

[0038] In certain embodiments, the sum of first electrode layers, second electrode layers, and dielectric layers is at least five, preferably at least seven, and in particular exactly nine. This achieves a balance between the achievable total capacitance of the capacitor and the effort required to manufacture it.

[0039] In embodiments, the base area of ​​the capacitor body in contact with the support measures between 1000 mm² 2 and 3000 mm 2 preferably between 1800 mm 2 and 2200 mm 2 , particularly preferably of about 2000 mm 2 . By using a capacitor body with the aforementioned dimensions, a balance is achieved between the total capacitance provided by the capacitor and its space requirement.

[0040] In some embodiments, the carrier has a conductor track structure to which at least one capacitor is electrically connected, in particular via the first capacitor terminal and the second capacitor terminal. This results in a particularly space-saving integration of the capacitor.

[0041] In various embodiments, the at least one first electrode layer, the at least one second electrode layer, and the dielectric layers extend essentially parallel to the substrate. Such a multilayer capacitor structure can be manufactured particularly easily and cost-effectively using methods already known from printed circuit board (PCB) manufacturing. In multilayer capacitors or circuits, shielding electrodes prevent signal coupling between different layers or components, thus improving signal quality and reliability. In some embodiments, the capacitor comprises at least one shielding electrode, preferably two shielding electrodes arranged above and below the internal electrodes. This provides electromagnetic shielding, which can help minimize unwanted parasitic capacitances and lead to a more stable and precise capacitance.At least one of the shielding electrodes can be designed to improve heat dissipation from the capacitor. Furthermore, at least one of the shielding electrodes can provide physical protection against environmental influences by shielding the internal electrodes from moisture, dirt, and / or other sources of damage. This increases the reliability and lifespan of the wireless system.

[0042] The problem is further solved using an inductive charging system for inductively charging a vehicle battery. The inductive charging system comprises a charging station with a power output coil and a wireless system according to one of the embodiments described herein.

[0043] The task is further solved by a vehicle having a wireless system according to one of the embodiments described herein.

[0044] The problem is further solved by a method for manufacturing a wireless system according to one of the embodiments described herein. The total capacitance of the capacitor is set by the following steps: a) providing an arrangement comprising, viewed in a stacking direction of the capacitor, a sequence of a first electrode layer and a dielectric layer; b) applying a second electrode layer to the dielectric layer to obtain a capacitor body; c) measuring a capacitance component of the capacitor body obtained in step b); d) modifying the capacitor body obtained in step b), in particular by eroding a portion of the second electrode layer, depending on the capacitance measured in step c), to obtain a capacitor body with the set capacitance component.e) Optionally, applying a further dielectric layer to the second electrode layer and repeating steps a) to d) to obtain a capacitor body comprising a plurality of first electrode layers and a plurality of second electrode layers arranged alternately with an interspersed dielectric layer along a stacking direction of the capacitor, wherein the capacitor has a set total capacitance defined by the sum of the set capacitance components.

[0045] Such a method makes it possible to manufacture a capacitor with a relatively large and defined total capacitance simply and cost-effectively.

[0046] In various implementations, the modification in step d) is carried out using a laser or chemically. Modifying the capacitor body with a laser to adjust the capacitance can be done particularly quickly and reliably. Chemical modification of the capacitor body can be carried out particularly simply and cost-effectively using methods already familiar from printed circuit board (PCB) manufacturing.

[0047] The invention will now be explained in more detail with reference to exemplary embodiments illustrated in the accompanying figures. These figures schematically show:

[0048] Figure 1: An electric vehicle above a wireless charging station; Figure 2: A first electrode layer of an embodiment of a

[0049] Multilayer capacitor in a top view;

[0050] Figure 3: A second electrode layer of an embodiment of a

[0051] Multilayer capacitor in a top view;

[0052] Figure 4: A sectional view of the multilayer capacitor along line AA in Figure 2 and BB in Figure 3;

[0053] Figure 5: A sectional view of the multilayer capacitor along line A'-

[0054] A' in Figure 2 and B'-B' in Figure 3;

[0055] Figure 6: A circuit arrangement of a wireless system with the component shown in the

[0056] Figures 4 and 5 show the multilayer capacitor.

[0057] The following examples of embodiment are merely illustrative of the subject matter of the invention and have no limiting effect. In principle, identical parts in the figures are designated with the same reference numerals.

[0058] Figure 1 shows a schematic side view of an electric vehicle 7 above a wireless charging station 102, which is located outside the electric vehicle 7 and includes a transmitter for transmitting an oscillating magnetic field. Above the charging station 102, which can also be referred to as a ground pad module (GPM), a wireless charging module 101 for charging a high-voltage battery 6 of the electric vehicle 7 is arranged inside the electric vehicle 7. The wireless charging module 101 can also be referred to as a vehicle module or car pad module (CPM). At least one of the two modules 101, 102 is configured as a wireless system according to one of the embodiments described herein. The ground pad module 102 and the vehicle pad module 101 together form an inductive charging system for the electric vehicle 7.

[0059] Figure 2 is a top view of a first electrode layer 1 located within a multilayer capacitor assembly. The first electrode layer 1 comprises a first internal electrode 1a and a third internal electrode 1b, which is electrically insulated from the first internal electrode 1a by dielectric material 1c. The first internal electrode 1a and the third internal electrode 1b can also be formed on a layer of dielectric material 1c. The first internal electrode 1a has a through-hole. The first electrode layer 1 also has a first coil terminal 12a and a second coil terminal 12b, each configured as a via.The first internal electrode 1a is electrically connected to the first coil terminal 12a via the inner circumference of its through-hole, whereas the third internal electrode 1b is not electrically connected to either the first coil terminal 12a or the second coil terminal 12b. As will be explained in more detail below, the third internal electrode 1b is electrically connected to the second assembly (also not shown) via a second capacitor terminal (not shown in Figure 2).

[0060] Figure 3 is a top view of a second electrode layer 2 located within an embodiment of a multilayer capacitor. The second electrode layer 2 comprises a second internal electrode 2a and a fourth internal electrode 2b. The second internal electrode 2a and the fourth internal electrode 2b are electrically insulated from each other by a dielectric material 2c, whereby the second internal electrode 2a and the fourth internal electrode 2b may also be formed on a layer of dielectric material 2c. The second internal electrode 2a has a through-hole. The second electrode layer 2 comprises a first coil terminal 12a and a second coil terminal 12b, each configured as a through-hole. The second internal electrode 2a is electrically connected to the second coil terminal 12b via the inner circumference of its through-hole.In contrast, the fourth internal electrode 2b is not electrically connected to either the first coil terminal 12a or the second coil terminal 12b. As will be explained in more detail below, the fourth internal electrode 2b is electrically connected to the second assembly (also not shown) via a first capacitor terminal (not shown in Figure 3). Figure 4 shows a sectional view through the capacitor body 11 of the capacitor 10 along line AA in Figure 2 and BB in Figure 3, each perpendicular to the top views shown in these figures. The first internal electrodes 1a and the second internal electrodes 2a are alternately applied to the dielectric layers 3 with their centers of gravity to the right and left, respectively.The dielectric layers 3 arranged between the first electrode layers 1 and the second electrode layers 2 electrically insulate the first internal electrodes 1a and the fourth internal electrodes 2b, as well as the second internal electrodes 2a and the third internal electrode 1b, from each other. In the embodiment shown in Figures 2 to 5, it is preferred, for reasons of simpler manufacturing, if the dielectric material arranged within the electrode layers 1, 2, and which electrically insulates the internal electrodes 1a, 1b and 2a, 2b arranged within the respective electrode layers, consists of the same dielectric material as the dielectric layers 3. However, it is also conceivable, in principle, that the dielectric material of one, several, or all of the dielectric layers 3 differs from the dielectric material arranged within the electrode layers 1, 2.Due to their design and superposition in the stacking direction of the capacitor body 11, the first internal electrodes 1a and the fourth internal electrodes 2b form a region in which the third internal electrode 1b and the fourth internal electrode 2b overlap each other in the stacking direction, as shown in Figure 5. The region in which the first internal electrodes 1a and the fourth internal electrodes 2b overlap forms a first capacitance component of the capacitor. The region in which the third internal electrodes 1b and the second internal electrode 2a overlap forms a second capacitance component of the capacitor. Finally, the region in which the third internal electrodes 1b and the fourth internal electrodes 2b overlap forms a third capacitance component of the capacitor. Since the first internal electrodes 1a are only electrically connected to the first coil terminal, respectively,Since the first internal electrodes 11a and the second internal electrodes 2a are connected to the first via 12a but not to the second coil terminal 12b, and the second internal electrodes 2a are only electrically connected to the second coil terminal or the second via 12b but not to the first coil terminal 12a, a voltage with reversed polarity can be applied to the first internal electrodes 11a and the second internal electrodes 2a. This creates a first capacitance component between the first internal electrodes 11a and the fourth internal electrodes 2b. A second capacitance component is created between the second internal electrodes 2a and the third internal electrodes 1b. In the embodiment shown in Figure 4, the dielectric base layer 4, arranged at the bottom in a stacking direction of the capacitor body 11, is formed by a support 5 on which the capacitor is arranged.

[0061] Figure 5 shows a sectional view through the capacitor body 11 of the capacitor 10 along lines A'-A' in Figure 2 and B'-B' in Figure 3, each perpendicular to the top views shown in these figures. This view reveals the third internal electrodes 1b and the fourth internal electrodes 2b, which are alternately applied to the dielectric layers 3, with the center of gravity to the left and right, respectively. The dielectric base layer 4, located at the bottom of the capacitor body 11 in a stacking direction, is formed by a support 5 on which the capacitor is mounted. Furthermore, the dielectric layers 3, arranged between the first electrode layers 1 and the second electrode layers 2, electrically insulate the third internal electrodes 1b and the fourth internal electrodes 2b from each other.As already described with reference to Figure 4, for reasons of simpler manufacturing, it is preferred that the dielectric material 1c, 2c within the electrode layers 1, 2 consists of the same dielectric material as the dielectric layers 3. The third internal electrodes 1b are not electrically connected to either the first via 12a or the second via 12b. The same applies to the fourth internal electrodes 2b. However, as will be explained in more detail below with reference to Figure 6, the third internal electrodes 1b are electrically connected to the second assembly (also not shown in Figure 5) via a first capacitor terminal, and the fourth internal electrodes 2b via a second capacitor terminal, which are not shown in Figure 5. Thus, a third capacitance component is formed between the third internal electrodes 1b and the fourth internal electrodes 2b.

[0062] Figure 6 shows a representation of a circuit arrangement of a wireless system 100 comprising the multilayer capacitor 10 shown in Figures 4 and 5. The wireless system 100 is for the inductive charging of a vehicle battery, which is not shown in Figure 6 but would be connected to the right in the circuit diagram shown in Figure 6. The wireless system 100 comprises a first assembly 20 and a second assembly 30, wherein the first assembly 20 includes a power-accepting coil 21 and the capacitor 10, which is outlined with dashed lines in Figure 6. The capacitor 10 shown in the figures has three capacitance components C1-C3, which are formed by laminating the first and second electrode layers with the dielectric layers and by arranging the individual internal electrodes within the first and second electrode layers, as described for Figures 2 to 5.Such a multilayer capacitor 10 with three capacitance components C1-C3 is simple and inexpensive to manufacture. Capacitor 10 and power pickup coil 21 form a power pickup resonant circuit. The second assembly 30 is connected to capacitor 10 via a first capacitor terminal 13a and a second capacitor terminal 13b.

[0063] Reference symbol list

[0064] 1 First electrode layer aa First internal electrode

[0065] 1b Third internal electrode

[0066] 1c Dielectric material

[0067] 2 Second electrode layer

[0068] 2a Second internal electrode

[0069] 2b Fourth internal electrode

[0070] 2c Dielectric material 3 Dielectric layer

[0071] 4 Dielectric soil layer

[0072] 5 carriers

[0073] 6 batteries

[0074] 7 vehicles

[0075] 10 Capacitor

[0076] 11 Capacitor bodies

[0077] 11 ' Capacitor body with set capacitance component

[0078] 12a First coil connection

[0079] 12b Second coil connection

[0080] 13a First capacitor connection

[0081] 13b Second capacitor connection

[0082] 20 First assembly

[0083] 21 Power consumption coil

[0084] 22 Housings of the first assembly

[0085] 30 Second assembly

[0086] 100 Wireless System

[0087] 101 Car Pad Module

[0088] 102 Ground Pad Module c Capacitance Component

[0089] Total capacity

Claims

P5507 DE 07.10.2025 - 20 - PATENT CLAIMS 1. Wireless system (100) for transmitting electrical energy to and / or from a vehicle (7) with - a first assembly (20), in particular a magnetic assembly, which performs at least one of the following two functions: o receiving an oscillating electromagnetic field and generating an alternating electric current; o receiving an alternating electric current and generating an oscillating electromagnetic field; - a second assembly (30), in particular an electronic assembly, which performs at least one of the following two functions: o receiving an alternating electric current and generating a direct electric current; o receiving a direct electric current and generating an alternating electric current; - wherein the first assembly (20) comprises a power-swapping coil (21) and at least one capacitor (10) which form a power-swapping resonant circuit, - wherein the capacitor (10) is designed as a multilayer capacitor with a capacitor body (11) having first electrode layers (1) and second electrode layers (2) which are arranged alternately with dielectric layers (3) inserted between them along a stacking direction of the capacitor (10), - wherein the first electrode layers (1) each have at least one first internal electrode (1a) and wherein the second electrode layers (2) each have at least one second internal electrode (2a), P5507 DE 07.10.2025 - 21 - - wherein the capacitor (10) further comprises a first coil terminal (12a), a second coil terminal (12b), a first capacitor terminal (13a), and a second capacitor terminal (13b), - wherein the first internal electrodes (1a) are connected to the first coil terminal (12a) and the second internal electrodes (2a) are connected to the second coil terminal (12b), and - wherein the second assembly (30) is electrically connected to the capacitor (10) via the first capacitor terminal (13a) and the second capacitor terminal (13b), wherein one of the first electrode layers (1), one of the second electrode layers (2) or a dielectric bottom layer (4) is formed by a support (5) on which the capacitor (10) is arranged.

2. The wireless system (100) according to claim 1, wherein the first coil connection (12a) is configured as a first via and the second coil connection (12b) as a second via, each extending within the capacitor body (11), in particular along the stacking direction of the capacitor (10).

3. The wireless system (100) according to claim 2, wherein the first via (12a) extends through the capacitor body (11) without touching the second internal electrodes (2a), and wherein the second via (12b) extends through the capacitor body (11) without touching the first internal electrodes (1a).

4. The wireless system (100) according to one of the preceding claims, wherein the first assembly (20) comprises a housing (22) in which the at least one capacitor (10) is arranged, wherein the power-accepting coil (21) is arranged outside the housing (22), and wherein the first coil connection (12a) and the second coil connection (12b) are passed through the housing (22). P5507 DE 07.10.2025 - 22 - 5. The wireless system (100) according to one of the preceding claims, wherein the power consumption resonant circuit comprises exactly one capacitor (10), wherein the capacitor (10) has a total capacitance (c ges ) provides, which is formed by a plurality of capacitance components (ci, cz, C3) which are connected in series and / or parallel.

6. The wireless system (100) according to any one of the preceding claims, - wherein the first electrode layer (1) comprises the first internal electrode (1a) and a third internal electrode (1b) which is electrically insulated from the first internal electrode (1a), - wherein the second electrode layer (2) comprises the second internal electrode (2a) and a fourth internal electrode (2b) which is electrically insulated from the second internal electrode (2a), - wherein the dielectric layer (3) arranged between the first electrode layer (1) and the second electrode layer (2) electrically insulates the first internal electrode (1a) and the fourth internal electrode (2b) as well as the second internal electrode (2a) and the third internal electrode (1b) from each other, so that - a first capacitance component (ci) is formed by the first internal electrode (1a) and the fourth internal electrode (2b), - a second capacitance component (ci) is formed by the second internal electrode (2a) and the third internal electrode (1b), and - a third capacitance component (cs) is formed by the third internal electrode (1b) and the fourth internal electrode (2b).

7. The wireless system (100) according to one of the preceding claims, wherein the capacitor body (11) has a width of at least 20 mm, preferably from 30 mm to 100 mm, measured perpendicular to the stacking direction, and a length of at least 30 mm, preferably from 30 mm to 100 mm, measured perpendicular to the stacking direction. P5507 DE 07.10.2025 - 23 - 40 mm to 150 mm, and has a thickness of 0.05 to 5 mm measured in the stacking direction.

8. The wireless system (100) according to one of the preceding claims, wherein the carrier (5) is a housing of the wireless system (100), in particular a housing (22) of the first assembly (20).

9. The wireless system (100) according to one of the preceding claims, wherein the dielectric layers (3) each comprise a ceramic, preferably each consisting substantially of a ceramic.

10. Method for manufacturing a wireless system (100) according to any one of claims 1-9, wherein a total capacity (c ges) of the capacitor (10) is set by the following steps: a) providing an arrangement comprising, viewed in a stacking direction of the capacitor (10), a sequence of a first electrode layer (1) and a dielectric layer (3); b) applying a second electrode layer (2) to the dielectric layer (3) to obtain a capacitor body (11); c) measuring a capacitance component (c) of the capacitor body (11) obtained in step b); d) modifying the capacitor body (11) obtained in step b), in particular by eroding a portion of the second electrode layer (2), depending on the capacitance (c) measured in step c), to obtain a capacitor body with the set capacitance component (11');e) Optionally, applying another dielectric layer (3') to the second electrode layer (2) and repeating steps a) to d) to obtain a capacitor body (11) having a plurality of first electrode layers (1) and a plurality of second electrode layers (2), which alternate with an interspersed dielectric layer (3) along a stacking direction of the; P5507 DE 07.10.2025 capacitors (10) are arranged, wherein the capacitor (10) has a set total capacitance (c) ges ) exhibits, which is defined by the sum of the set capacity components (c).

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