DE102022108335A1 - POWER RAIL WITH ACTIVE COOLING - Google Patents

Abstract

The present invention relates to a busbar (100), wherein the busbar (100) forms a receptacle (102) for a cooling cell (104) and the cooling cell (104) is arranged in the receptacle (102), the receptacle (102 ) is designed to thermally couple the cooling cell (104) to the busbar (100), the cooling cell (104) having connections (118) for a cooling medium and being designed to actively control the temperature of the busbar (100).

Description

Technical area

The present invention relates to a busbar with a cooling cell.

State of the art

The present invention is described below primarily in connection with a high-voltage distribution system of a vehicle.

In an electrically powered vehicle, drive energy can be transmitted via busbars. Busbars are solid sheet metal strips made of a metal material with good electrical conductivity. The busbars provide a large cable cross-section to enable low power loss.

In particular, when charging a traction battery of the vehicle, charging is carried out with ever higher powers in order to increase the state of charge of the traction battery within a short period of time. Even busbars with large cable cross-sections can become warm.

Description of the invention

An object of the invention is therefore to provide an improved busbar using the simplest possible design means. An improvement here can, for example, relate to a reduced temperature of the busbar, particularly when charging the traction battery.

The task is solved by the subjects of the independent claims. Advantageous developments of the invention are specified in the dependent claims, the description and the accompanying figures.

In the approach presented here, a cooling cell is thermally coupled to the busbar. Interfaces between the busbar and adjacent components are also thermally connected to the cooling cell via the busbar.

With the approach presented here, the power loss that occurs when charging the traction battery can be absorbed in the busbar. Furthermore, increased power loss at the interfaces due to a potentially increased contact resistance of the interfaces can be conducted through the busbar to the cooling cell and also be absorbed. In this way, the temperature of the busbar, the interfaces and ideally also adjacent components can be limited during charging.

According to one aspect of the invention, a busbar is presented, wherein the busbar forms a receptacle for a cooling cell and the cooling cell is arranged in the receptacle, the receptacle being designed to thermally couple the cooling cell to the busbar, the cooling cell having connections for a Has cooling medium and is designed to actively control the temperature of the busbar.

The following description explains designs of the cooling cell and its connection to the busbar. Implementations of the cooling cell for active cooling of the busbar are explained in detail. Only as a possible alternative, it is partly described how the cooling cell could be designed if passive cooling of the busbar is desired, whereby it is pointed out that passive temperature control of the busbar is not an embodiment of the busbar specified here, but in one by the applicant another application filed in parallel on the same day is claimed.

A busbar can be a strip of sheet metal. The busbar provides a line cross-section across a width and thickness for transmitting electrical power. The busbar can, for example, be made of a copper material, an aluminum material or iron material such as steel.

The busbar can be arranged, for example, between a charging socket of an electrically powered vehicle and a traction battery of the vehicle. In particular, the busbar can be arranged in the area of the charging socket.

A cold cell can have a housing made of a heat-conducting material. The housing can in particular be made of a metal material. A cooling medium can be passed through the cooling cell via connections and transport away the heat energy generated due to the power loss of the busbar.

Alternatively, the cooling cell can be passive and a heat storage medium can be arranged in the housing. The heat storage medium can absorb the heat energy during the charging process and release it again after the charging process. This allows a predefined amount of energy to be absorbed before the busbar reaches a predefined temperature. In particular, the heat storage medium can have a higher heat capacity than a material from which the busbar is made and can therefore absorb and store more heat energy per volume than in the busbar is the case. The material of the heat storage medium generally differs from a material of a housing surrounding the heat storage medium and generally has a significantly higher heat capacity than the material of the housing. For example, the specific heat capacity of the heat storage medium may be more than 50%, more than 100% or even more than 200% higher than that of the material of the bus bar or the housing.

A receptacle can be adapted to a contour of the cooling cell and provide the largest possible heat transfer surface between the busbar and the cooling cell. The cooling cell can be cylindrical or prismatic, for example.

The busbars of a pair of busbars can have different electrical potentials during operation. The busbars can be electrically insulated from each other. Clearance and creepage distances can be maintained between the busbars.

The busbars of the pair of busbars can be arranged symmetrically to one another. Through a symmetrical arrangement, electromagnetic radiation from the busbars can compensate for each other. The symmetrical arrangement allows the radiation from the pair of busbars to be reduced overall.

The cooling cell of the pair of busbars can have two partial cells that are electrically insulated from one another. A sub-cell and a busbar can be connected to one another in an electrically conductive manner. The partial cells can be at different electrical potentials. By electrically separating the sub-cells, good heat transfer from the current cell to the respective sub-cell can be achieved, since no electrical insulation is required there.

The cooling cell can be electrically insulated from the busbar. If an electrically conductive cooling medium flows through the cooling cell, current flow through the cooling medium can be prevented by electrically separating the cooling cell and the busbar. In order to electrically insulate the cooling cell from the busbar, a heat-conducting insulating material can be arranged between the cooling cell and the busbar. In addition, clearance and creepage distances between the cooling cell and the busbar can be maintained. Alternatively, an electrically insulating cooling medium can be used.

In the area of the holder, two electrically insulating spacers can be arranged between the cooling cell and the busbar. A gap formed by the spacers between the cooling cell and the busbar can be filled with an electrically insulating and heat-conducting paste. An electrically insulating and heat-conducting paste can be called a gap filler. The gap filler is configured to compensate for any tolerances and resulting air gaps and to ensure optimal heat transfer. Side edges of the gap may be closed to trap the paste in the gap. A spacer can close at least one side of the gap. The spacers can be arranged on opposite sides of the gap. The edges of the gap between the spacers can be closed by electrically insulating closures.

The cooling cell can be arranged between two electrically insulating contact protection caps. The spacers can be formed by the contact protection caps. Touch protection caps can, for example, consist of a plastic material. The contact protection caps can provide the necessary air and creepage distances to electrically insulate the cold cell. The spacers can be arranged along an edge of the contact protection caps.

In the area of the holder, an electrically insulating film can be arranged between the cooling cell and the busbar. The film can be arranged in addition to the paste between the cooling cell and the busbar to protect against a puncture.

A sensor system for mapping a temperature in the area of the recording in a temperature value can be arranged between the cooling cell and the busbar. The sensor system can be designed, for example, as a printed circuit in the film. The sensors can also be integrated into the spacer. The cooling capacity of the cold cell can be regulated using sensors. Likewise, current flow through the busbar can be limited when a temperature threshold is exceeded.

The busbar can have at least one tab in the area of the receptacle for fastening the cooling cell to the busbar and/or for fastening the busbar to a structural component. A tab can be an extension of the busbar. Alternatively, the tab can also be part of an electrically insulating spacer. The tab can protrude from the busbar and provide space for attachment next to the busbar.

Alternatively, the cooling cell can be electrically connected to the busbar. If the cool If an electrically insulating cooling medium flows through the cell or is designed as a passive cooling cell, the cooling cell can rest directly on the busbar and have the same electrical potential as the busbar. Thanks to the electrically conductive connection, the recording can be carried out easily and cost-effectively. The electrically conductive connection has a low heat transfer resistance. Thanks to the direct connection, the cooling cell can absorb heat energy particularly well.

The busbar can at least partially depict a contour of the cooling cell in the area of the receptacle. The busbar can be a negative form of at least a portion of the contour of the cooling cell. By mapping the contour, the largest possible heat transfer area between the busbar and the cooling cell can be achieved.

The busbar can enclose the cooling cell in the area of the holder by more than 180°. The cooling cell can then mechanically lock into the holder. For this purpose, the busbar can be elastically deformed in the area of the holder when it snaps into place. The busbar can, for example, have a slightly smaller bending radius in the area of the receptacle than the contour of the cooling cell. This means that the busbar is slightly pre-tensioned and presses against the housing of the locked cooling cell with a resulting restoring force. Due to the resulting surface pressure, a low heat transfer resistance between the receptacle and the cooling cell can be achieved.

The busbar can have at least one holding element arranged in the area of the receptacle. The cooling cell can be arranged between the holding element and the busbar. The holding element can at least partially depict the contour of the cooling cell and at least partially enclose the cooling cell. A holding element can be attached to the busbar. The holding element can, for example, consist of a plastic material. The holding element can enclose the part of the contour that is not enclosed by the receptacle. The holding element can fix the cooling cell in the receptacle.

The holding element can form the receptacle and be arranged between the busbar and the cooling cell. The holding element can at least partially enclose the cooling cell. In particular, the holding element can completely enclose the contour of the cooling cell. The holding element can be made of a heat-conducting, electrically insulating material. The holding element can electrically separate the cooling cell from the busbar. The holding element allows the busbar to have a simplified geometry.

The busbar can form at least one wall of the cooling cell in the area of the receptacle. The busbar can be an integral part of the cooling cell. The cooling cell can then be arranged directly on the busbar. The direct connection results in very good heat transfer from the busbar to the cooling cell.

Cooling cell connections can run through the power rail. An inlet and an outlet for the cooling medium can be arranged in openings through the busbar. By arranging the connections in the busbar, the cooling cell can be designed very simply.

The busbar can have a connection panel for a pin of a charging socket adjacent to the receptacle. The busbars can also have an interface to a high-voltage distribution system of the vehicle adjacent to the receptacle. The busbar can be arranged directly behind the charging socket. The busbar can be referred to as an adapter busbar and form a connection between the charging socket and the high-voltage distribution system. Due to the immediate proximity to the charging socket, heat generated in the charging socket due to a contact resistance in the charging socket can be easily absorbed.

The connection field can be designed to accommodate different pins. The different pins may be required for different charging socket standards. Thanks to the universal mount, the busbar can be designed as a common part for different charging socket standards.

The cooling cell can have ribs aligned with an interior of the cooling cell. Ribs can increase a heat transfer area to a cooling medium or a heat storage medium in the interior. Increased cooling performance can be achieved due to the increased heat transfer surface.

The cooling cell can have at least one slat running through an interior of the cooling cell. A fin can provide additional heat transfer surface to a cooling medium or a heat storage medium in the interior. The additional heat transfer surface allows increased cooling performance to be achieved. The slat can be flat or curved. The slat can stiffen the cooling cell.

The at least one slat can be held by the ribs. The ribs can be aligned in one direction of the slat. The slat can be inserted between at least two of the ribs. The ribs can be slightly elastically deformed by the slat and clamp the slat with a resulting restoring force.

The at least one lamella can define a flow path for the cooling medium from the inflow to the outflow in the interior. The cooling medium can flow in opposite directions on opposite sides of the fin. The fin allows the flow path to be extended. Likewise, a flow cross section for the cooling medium can be reduced, which can lead to an increased flow rate and improved heat transfer to the cooling medium.

The at least one lamella can have flow openings for the cooling medium. The cooling fin can then extend through the entire interior. The cooling medium can flow from one side of the slat to the other side of the slat via the flow openings.

Alternatively, the at least one lamella can be shorter than the interior space in order to form the flow path for the cooling medium. The cooling medium can then flow around one edge of the lamella from one side to the other.

The cooling cell can have at least two slats in the interior. The cooling fins can protrude into the interior from opposite sides. The flow path can be made serpentine by slats on opposite sides. This allows the flow path to be extended and the flow cross section to be reduced.

The slats can be used to modify or optimize the flow mechanics within the cooling cell. Through the shape, form, surface, as well as through targeted elevations and breakthroughs, laminar or turbulent flows can be consciously achieved.

The heat storage medium can be a phase change material. A phase change material can be referred to as a latent heat storage material. The phase change material can absorb or release thermal energy at a substantially constant temperature while undergoing a phase change. For example, a paraffin material or salt material can absorb or release large amounts of heat energy at its melting point at its melting temperature. The temperature only rises or falls again when the phase change is essentially complete. The amount of heat energy that can be absorbed can be adjusted via a volume of the phase change material. The melting point or the melting temperature can be adjusted by a material composition of the phase change material. The phase change material allows the temperature of the busbar to be kept within a predetermined temperature range during the charging process. The thermal energy can be released slowly after charging.

The at least one slat can have compensating openings. The fill level of the heat storage medium within the cooling cell can be equalized through compensation openings. However, the slat can prevent liquid heat storage material from sloshing back and forth.

The heat storage medium can incompletely fill the interior space. If the cooling cell is incompletely filled, thermal expansion of the heat storage medium can be taken into account.

A remaining volume of the interior can be filled with a noble gas. A noble gas can at least slow down or even prevent chemical changes in the heat storage medium over time. This means that the cooling cell can have a long service life.

Short character description

• 1 eine Darstellung einer Stromschiene gemäß einem Ausführungsbeispiel;
• 2 eine Schnittdarstellung einer prismatischen Kühlzelle an einer Stromschiene gemäß einem Ausführungsbeispiel;
• 3 eine Darstellung einer passiven Kühlzelle für eine Stromschiene gemäß einem Ausführungsbeispiel;
• 4 bis 10 Darstellungen von Kühlzellen in Aufnahmen von Stromschienen gemäß Ausführungsbeispielen;
• 11 eine Darstellung eines Stromschienenpaars gemäß einem Ausführungsbeispiel;
• 12 eine Schnittdarstellung einer Kühlzelle für ein Stromschienenpaar gemäß einem Ausführungsbeispiel; und
• 13 bis 14 Darstellungen von Kühlzellen in Aufnahmen von Stromschienenpaaren gemäß Ausführungsbeispielen.

An advantageous embodiment of the invention is explained below with reference to the accompanying figures. Show it:

• 1 a representation of a busbar according to an exemplary embodiment;
• 2 a sectional view of a prismatic cooling cell on a busbar according to an exemplary embodiment;
• 3 a representation of a passive cooling cell for a busbar according to an exemplary embodiment;
• 4 until 10 Representations of cooling cells in recordings of busbars according to exemplary embodiments;
• 11 a representation of a pair of busbars according to an exemplary embodiment;
• 12 a sectional view of a cooling cell for a pair of busbars according to an exemplary embodiment; and
• 13 until 14 Representations of cooling cells in recordings of pairs of busbars according to exemplary embodiments.

The figures are schematic representations and only serve to explain the invention. Elements that are the same or have the same effect are consistently provided with the same reference numerals.

Detailed description

1 shows a representation of a busbar 100 with a receptacle 102 for a cooling cell 104 according to an exemplary embodiment. The receptacle 102 for the cooling cell 104 is formed by a three-dimensional contour of the busbar 100. The receptacle 102 thermally couples the cooling cell 104 to the busbar 100. The cooling cell 104 acts as a heat sink and cools the busbar 100. The busbar 100 is essentially a stamped and bent strip of sheet metal. A line cross section of the busbar 100 results from a material thickness of the busbar 100 and a width of the busbar at a narrowest point.

In one exemplary embodiment, the busbar 100 has a connection panel 106 for a pin 108 of a charging socket of a vehicle and an interface 110 to a high-voltage distribution system 112 of the vehicle. In this way, the cooling cell 104 can absorb heat loss at connection points during a charging process of the vehicle. The connection panel 106 and the interface 110 are angled relative to a central part of the busbar 100. Pin 108 is replaceable here, for example. In particular, the busbar 100 can be used as an adapter busbar for different charging socket standards (country variants).

The receptacle 102 with the cooling cell 104 is arranged in the middle part between the connection panel 106 and the interface 110. The busbar 100 connects the pin 108 and the high-voltage distribution system 112 to one another in both an electrically and thermally conductive manner. Both the pin 108 and the high-voltage distribution system 112 are thermally coupled to the cooling cell 104 via the receptacle 102. The cooling cell 104 can thus heat the charging socket and at least part of the high-voltage distribution system.

The cooling cell 104 is aligned here along the busbar 100. The receptacle 102 therefore consists of two tabs 114 that protrude laterally beyond a side edge of the busbar 100. The tabs 114 are bent out of a main extension plane of the busbar 100 in the area of the receptacle 102 and rest on a lateral surface 116 of the cooling cell 104. The tabs 114 enclose a large part of the lateral surface 116. The receptacle 102 therefore has a large heat transfer area to the cooling cell 104.

The cooling cell 104 can be shaped differently depending on the space available. The cooling cell 104 can be cylindrical or prismatic, for example. The recording 102 is adapted to the shape of the cooling cell 104. Here the cooling cell 104 is cylindrical, for example.

The cold cell 104 can be connected to a cooling system. Then the cooling cell 104 can be referred to as an active cooling cell. The cooling cell 104 can also be designed to be passive and provide a defined heat storage capacity.

As an active cooling cell 104, a cooling medium is passed through an interior of the cooling cell 104 via connections 118. The cooling medium transports heat from the busbar 100 to a heat sink of the vehicle, for example during the charging process. For example, depending on requirements, oil, coolant or refrigerant can be passed through the cooling cell 104. The cooling cell 104 can be connected to its own cooling circuit. The cooling cell 104 can also be connected to a cooling circuit of a traction battery of the vehicle. Likewise, the cooling cell 104 can be connected to an air conditioning system of the vehicle.

As a passive cooling cell 104, a heat storage medium is arranged in the interior of the cooling cell 104. For example, the heat storage medium absorbs heat during the charging process and releases the heat again with a time delay after the charging process. The heat storage medium can have a large heat capacity. For example, the heat storage medium can be a phase change material. The phase change material can absorb and release large amounts of heat as latent heat during a phase change at an approximately constant temperature.

2 shows a sectional view of a prismatic cooling cell 104 on a busbar 100 according to an exemplary embodiment. The busbar 100 essentially corresponds to the busbar in 1 . The cooling cell 104 here has a square cross section. As opposed to 1 Here, the cooling cell 104 is aligned transversely to the busbar 100 and the busbar 100 is bent around the cooling cell 104 to form the receptacle 102. In the present embodiment, the receptacle 102 encloses the cooling cell 104 on three of four sides.

Here the cooling cell 104 is galvanically isolated from the busbar 100. For this purpose, a heat-conducting insulator is arranged between the cooling cell 104 and the busbar 100 in the area of the receptacle 104.

In one embodiment, the insulator is designed as a paste-like material that is arranged in a gap 200 between the cooling cell 104 and the busbar 100. The paste-like material can be referred to as a gap filler. The material is shown here transparently. The gap 200 is created by a spacer 202 of the receptacle 102. The spacer 202 closes a side edge of the gap 200 and prevents the pasty material from escaping to the side and prevents the busbar 100 from being placed directly on the cooling cell 104.

In one exemplary embodiment, the cooling cell 104 is further enclosed by an electrically insulating film 204 in order to reliably prevent breakdowns through the insulator.

In one exemplary embodiment, the cooling cell 104 has ribs 210 projecting from a wall 206 of the cooling cell 104 into an interior 208 of the cooling cell. The wall 206 is, for example, an extruded profile made of an aluminum material. The ribs 210 increase a heat transfer area of the wall 206 to the medium arranged in the interior 208.

In one exemplary embodiment, 208 slats 212 are arranged in the interior. The slats 212 divide the interior 208 into partial areas 214. The slats 212 also increase the heat transfer area to the medium.

In an active design of the cooling cell 104, the slats 212 define a flow path for the medium through the interior 208. In a passive design of the cooling cell 104, the slats 212 act as baffles and prevent the medium from sloshing back and forth in the interior 208.

In one exemplary embodiment, the ribs 210 are designed in pairs, with a gap between the ribs 210 of a pair each corresponding to a thickness of the slats 212. The slats 212 are each inserted between a pair of ribs 210 on opposite sides.

In one embodiment, the ribs 210 are aligned radially to a center axis of the interior 208. The slats 212 are arcuate.

3 shows a representation of a passive cooling cell 104 for a busbar according to an exemplary embodiment. The cooling cell 104 essentially corresponds to the illustration in 1 . Here a heat storage medium 300 is arranged in the interior 208. The heat storage medium 300 fills the interior 208 up to a predefined filling level 302. A remaining volume of the interior 208 is empty. The remaining volume can be filled with air or a noble gas 304, for example. A negative pressure can be set in the volume. The empty volume allows the heat storage medium 300 to expand unhindered when heated.

In one embodiment, the heat storage medium 300 is a phase change material 306. The phase change material 306 is, for example, a salt material or a paraffin material. The phase change material 306 is solid in a cold state and liquid in a heated state. During the phase change from solid to liquid, the phase change material 306 absorbs heat of fusion until it is completely melted without significantly changing its temperature. During the phase change from liquid to solid, the phase change material 306 releases heat of solidification until it has completely solidified without significantly changing its temperature. The phase change material 306 can therefore absorb and release large amounts of thermal energy during the phase change at an approximately constant temperature.

In one exemplary embodiment, slats 212 are connected to at least one cover 308 of the cooling cell 104 and protrude into the interior 208. The slats 212 increase the heat transfer area to the heat storage medium 300. The slats 212 are shorter here than the interior 208. This results in a distance between one End of the slats 212 and an opposite cover 308 of the cooling cell 104.

In one exemplary embodiment, 308 slats 212 are arranged on both covers. The slats 212 protrude alternately from both covers 308 into the interior 208.

In one exemplary embodiment, the slats 212 have compensation openings 310. The liquid heat storage medium 300 can compensate for level differences within the cooling cell 104 through the compensation openings.

4 until 10 show representations of cooling cells 104 in recordings 102 of busbars 100 according to exemplary embodiments.

In 4 The cooling cell 104 is cylindrical and arranged lengthwise next to the busbar 100. The receptacle 102 consists of a single tab 114 projecting laterally from the busbar 100. The tab 114 is bent in the shape of a hook. The tab 114 is angled transversely to the busbar 100 at a transition to the flat busbar 100 and from there runs in an arc around the cooling cell 104. The receptacle 102 thus largely reproduces the contour of the cooling cell 104 and has a wrap angle of more than 180 °. The wrap angle can be between 190° and 230°, for example. Here the wrap angle is approximately 210°. When mounting the cooling cell 104 in the receptacle 102, the tab 114 is elastically deformed and springs back after the deformation. As a result, the cooling cell 104 is held securely in the receptacle 102. The arch of the tab 114 can also have smaller dimensions than the cooling cell 104 when empty. As a result, the tab 114 is prestressed during assembly and clamps the cooling cell 104 with a resulting prestress. This results in good heat-conducting contact between the receptacle 102 and the cooling cell 104.

In 5 the tab 114 is not angled and runs in an arc around the cooling cell 104 until one end of the tab 114 rests against the busbar 100 again. The receptacle 102 therefore has a wrap angle of 270°. At the end of the tab 114 there is a flange 500 which is attached to the busbar 100 or at a beginning of the tab 114.

In one embodiment, the tab 114 has a bending area 502 with reduced bending resistance to simplify the assembly of the cooling cell 104. Through the bending area 502, the receptacle 102 can be bent open with reduced effort and the cooling cell 104 can be arranged in the receptacle 102. In the bending region 502, a cross-sectional area of the tab 114 is reduced. Here, a series of openings 504 are arranged in the tab 114 in the bending area 502.

The cooling cell 104 here is an active cooling cell with connections 118. The connections 118 are arranged in one of the covers 308 of the cooling cell 104.

The busbar 100 in 6 essentially corresponds to the busbar in 4 . Here the busbar 100 has an additional holding element 600. The holding element 600 is connected to the receptacle 102. The holding element 600 complements the receptacle 102. The receptacle 102 and the holding element 600 each have a wrap angle of 180° around the cooling cell 104. Together, the receptacle 102 and the holding element 600 have a wrap angle of 360°. The holding element 600 is connected to the receptacle 102 or the busbar 100 via flanges 500.

The busbar 100 in 7 essentially corresponds to the busbar in 5 . In addition, the busbar 100 has a holding element 600 as in 5 on. The holding element 600 is connected to the receptacle 102 via a flange 500. The receptacle 102 and the holding element 600 together have a wrap angle of 360° around the cooling cell 104. The holding element 600 here is in particular a plastic part made of a heat-conducting plastic. The holding element 600 has thickenings 700 for attachment to the flange 500 and the busbar 100.

In 8th the receptacle 102 is completely formed by the holding element 600. The holding element 600 completely encloses the lateral surface 116 of the cooling cell 104. The holding element 600 has a foot 800 which lies flat against the busbar 100.

In 9 The cooling cell 104 has a cuboid shape and rests with one flat side lengthwise on the busbar 100. Two tabs 114 arranged on opposite sides of the busbar 100 are aligned transversely to the busbar 100 and form the receptacle 102. The holder itself acts as a spacer to the rail and can have a recess towards the rail. This recess can be filled with gap filler, for example. The tabs 114 lie on opposite narrow sides of the cooling cell 104. A holding element 600 rests on the second flat side of the cooling cell 104 and fixes the cooling cell 104 in the receptacle 102.

Is the cold room as in 9 As shown, the tabs 114 also serve, if necessary, to fix one or more busbars 100 to the environment, for example to the body or adjacent components.

In one exemplary embodiment, connections 118 of the cooling cell 104 are arranged on opposite end faces of the cooling cell 104. The holding element 600 has recesses 900 for the connections 118.

In 10 The busbar 100 forms a floor 1000 of the cooling cell 104 in the area of the receptacle 102. The cooling cell 104 is therefore cohesively connected to the busbar 100. The direct contact results in a low heat transfer resistance to the cooling cell 104.

In one exemplary embodiment, the connections 118 of the cooling cell run through the busbar 100. This means that the busbar 100 can also be installed in special space conditions. Alternatively, the connections 118 are also opposite each other.

11 shows a representation of a pair of busbars 1100 according to an exemplary embodiment. The pair of busbars 1100 consists of two busbars 100, each with a receptacle 102. The busbars 100 essentially correspond to the busbars in the previous figures. In contrast, here a single cooling cell 104 is thermally coupled to both busbars 100. For this purpose, the cooling cell 100 is arranged between the two receptacles 102. The recordings 102 are arranged symmetrically to a center plane of the cooling cell 104. Since the busbars 100 are at different electrical potentials, the cooling cell 104 is galvanically isolated from at least one of the busbars 100 and appropriate clearance and creepage distances are maintained. The recordings 102 therefore wrap around the cooling cell 104 by less than 180°.

The cooling cell 104 is aligned along the busbars. The busbars 100 lie next to each other in a common plane before and after the recordings 102. Shortly before and after the recordings 102, the busbars 100 are twisted by approximately 90°. In the area of the receptacles 102, the busbars 100 are approximately deformed into half-shells, which essentially correspond to the contour of the cooling cell 102.

In one exemplary embodiment, the cooling cell 104 has contact protection caps 1102. The contact protection caps 1102 cover both lids of the cooling cell 104 and each form a spacer 202. The spacers 202 rest on opposite ends of the receptacle 102 and form the gap 200 between the busbars 100 and the cooling cell 104. The gap 200 is filled with the electrically insulating, heat-conducting material.

In one exemplary embodiment, a connection 118 for cooling medium is arranged in both covers. The connection 118 penetrates the contact protection cap 1102. At the bushing, the contact protection cap has a contact protection collar 1104 in order to maintain the clearance and creepage distances.

12 shows a sectional view of an active cooling cell 104 for a pair of busbars according to an exemplary embodiment. The cooling cell 104 is divided into two sub-cells 1200 that are electrically insulated from one another. An insulator 1202 is arranged between the sub-cells 1200. Each sub-cell 1200 can thus have its own electrical potential. Each sub-cell 1200 has a connection 118 for an electrically insulating cooling medium. An overflow channel 1204 connecting the partial cells 1200 runs through the insulator 1202. As a result, the same volume flow flows through both partial cells 1200, but they are electrically separated from one another.

In one exemplary embodiment, two slats 212 are arranged in the interior 208 of each partial cell 1200. The slats 212 are shorter than the interior 208 and protrude from opposite sides into the respective interior 208. The slats 212 form a meandering flow path 1206 for the cooling medium. The flow path 1206 extends from the respective connection 118 to the overflow channel 1204. Both interior spaces 208 are completely flowed through through the slats 212.

If the slats 212 are designed to be as long as the interior 208, the slats 212 can have overflow openings. The overflow openings connect the spaces between the slats 212 and form the flow path 1206.

13 until 14 show representations of cooling cells 104 in recordings 104 of pairs of busbars 1100 according to exemplary embodiments.

In 13 is a cooling cell 104 with electrically insulated sub-cells 1200 as in 12 arranged transversely between the busbars 100 of the pair of busbars 1100. The partial cells 1200 are at the respective electrical potential of the busbars 100. The busbars 100 essentially correspond to the illustration in 2 . In contrast, the cooling cell 104 here is cylindrical and the receptacles 102 are therefore arcuate as in 4 . The receptacles 102 each encompass more than half of a circumference of the partial cells 1200. The cooling cell 104 is held in the receptacle 102 by one holding element 600 per busbar 100.

The busbars 100 are approximately identical here and run essentially parallel next to each other from connection panels 106 for pins of a charging socket to interfaces 110 of a high-voltage distribution system 112. In the area of the interfaces 110, the busbars 100 have a height offset in order to ensure a parallel arrangement of busbars of the high-voltage distribution system 112 make possible.

In 14 is the cold cell 104 as in 13 arranged transversely to the busbars 100. In contrast, the busbars are 100, as in 11 electrically insulated from the cooling cell 104 using spacers. The busbars 100 run in the area of the receptacles 102 on opposite sides along the cooling cell 104 and cross each other there without touching each other. The receptacles 102 each enclose less than half the circumference of the cooling cell 104 in order to maintain the air and creepage distances.

Possible embodiments of the invention are summarized again below or presented with a slightly different choice of words.

Modular and scalable cooling units are presented.

Charging systems basically consist of a charging socket, a cable and a switch box on or in the battery. The battery is charged using direct current (DC) or alternating current (AC). The performance is many times higher when charging with direct current than when charging with alternating current.

For charging with direct current and the power transmitted with it, cables, components and interfaces are dimensioned accordingly larger. Outputs of around 700 amps at around 800 volts are currently possible.

However, the current trend is that the current intensity increases disproportionately and thus the power loss in the form of heat increases squared. One possibility is to further adapt or enlarge the cross sections; another possibility is to specifically cool the system.

In order to design effective cooling, it is important to understand where in the system heat can arise. What should be mentioned here are primarily the transition and line resistances. The contact resistance always arises at interfaces, i.e. from the charging socket outlet to the cable or from pin to socket. The cable resistance increases the smaller the cross-section of a cable is chosen and the warmer the cable itself becomes.

In order to cool individual components in the system charging path, the expenses must be viewed as very different. On the one hand, this is due to the topology and complexity of a component itself, but on the other hand it is also due to the scope in terms of package, accessibility and material mix.

An example would be the cooling of a pipe. Through active cooling, the cross section can be reduced - i.e. less weight and costs, as well as a smaller package. However, the cooling itself can offset the advantages, as the costs increase, the package does not become smaller and the complexity can be higher and robustness may be lower.

Another aspect in the context of effort and benefit is the requirement not to develop systems and components that are highly individualized down to the last detail.

The Cool Cells approach presented here presents a modular, scalable, active or passive portfolio of cooling units that can be integrated into the hotspots of a charging system with as little individualization as possible. For this purpose, areas and parts are identified in components that enable this approach and increase the potential through their design or cost-effective adaptation.

The connection field offers the potential to redesign the rail for each country variant. The rear position also provides good accessibility for service. Furthermore, the connection panel is in direct proximity to power losses generated by contact resistances, for example at pins and the transition to the high-voltage distribution system HVDS (high-voltage double rail). Therefore, a design and modification of the rail (DC bar) to accommodate a standardized, modular and scalable cooling module is proposed here. The cooling module can be designed both actively and passively and can be designed both on potential and galvanically isolated from it.

The cooling module can be designed as a cylinder or cube and, due to the 2D and/or point symmetry and/or the multiple 3D axis symmetry, enables a high degree of flexibility and a high potential for identical parts. The bending-stamping process generally offers a high degree of flexibility for integrating a cooling module.

A section of the cooling module, for example the cylinder surface, is partially enclosed or connected by the bending-stamping grid and thus heat is dissipated. The cooling module can be fixed directly using the bending-stamping grid.

For the design and type of integration, it is important to take into account the type of cooling circuit inside or outside the vehicle. Cooling systems with a galvanically non-insulating, i.e. current-conducting, cooling fluid generally require insulation between the cool cell and the current-carrying component (section). Such a cooling fluid is, for example, a water-glycol mixture, e.g. from the battery cooling circuit.

Cooling systems that are based on mineral, synthetic or similar oil do not conduct electricity. Here the cooling can take place directly on the potential or the current-carrying component. However, the clearance and creepage distances compared to other components must be maintained during integration.

Another very effective option is to integrate the CoolCell as a “consumer” of the air conditioning refrigerant cycle. Here, the cool cell is flowed through by a fluid that has been cooled down by the air conditioning system or the compressor. Since the temperature differences to be achieved between the cool cell and the heat source are relatively large, this method would be very powerful.

A cooling source can be used for thermal management. The cooling source can be located in the vehicle or outside the vehicle. In the vehicle, a cooling module can be supplied, for example, by an S-Box in the vehicle, an HV storage unit in the vehicle, the cooling circuit of the air conditioning system, or it can be self-sufficient. The cooling module can be supplied from outside the vehicle, for example through the charging station.

The Cool Cell/s can alternatively be integrated into an independent cooling circuit system. In addition to the necessary lines, a heat exchanger, a reservoir or expansion tank and a pump are integrated.

Cool cells can therefore be integrated into different types of cooling circuits. Cool Cells can be integrated individually or multiple times into components/groups.

Several cooling modules can be connected in series or parallel. The serial and parallel circuit can be combined according to the amount of heat.

Cooling modules can also be operated via different independent circuits. In this case, the systems would not overlap, especially if the fluids are different.

The module basically consists of three basic forms. Round, cubic and flat. Depending on the form of integration, the appropriate form can be chosen. For the sake of simplicity, the round shape is usually shown in the examples shown in the figures. However, the structure and integration can largely be transferred to the other forms.

What all shapes have in common is that the lateral surface is largely in contact with the heat source for heat transfer or cooling effect. Depending on the dimensions or length of the Cool Cell itself, the front surface itself may be more suitable. A fundamental distinction is made between cooling at potential, in which the module is energized, and isolated cooling, in which the module has no current-conducting contact with the potential, i.e. is galvanically isolated from the potential.

With a finned profile heat sink, the module has one or more guide fins, depending on the version. These fins guide the cooling medium through the module. The aim is to maximize the flow length and optimize the fluid mechanics without modifying the standardized base body, so that the heat absorption capacity of the medium is optimally used.

The slats are inserted and guided and fixed by the cooling fins themselves. The slats have a gap to the heat sink or openings through which the medium can flow.

In a passive design, the module is closed on both sides and there are no entrances or exits. Inside the module is felt with a heat accumulator. The heat storage is, for example, a latent heat storage or phase change material (PCM).

On the front side, i.e. on the lids, ribs can be applied to improve the heat input. These can have compensation holes in order to achieve a uniform filling level across the cell. The volume expansion of a PCM, for example, is taken into account by a filling level of approx. 70-90% and the compression capacity of the gas or air is utilized. A proportion of the PCM volume shape to the heat transfer area size to the PCM can be set depending on the application. For example, with a steep temperature gradient, the number of heat transfer surfaces can be increased to better 'activate' the PCM.

In an active structure, a slat made of sheet metal, for example, can be fixed on the cover between the connections. This is designed so that the inlet or outlet is not covered. If possible, the lamella forms two sections of the same size and, if possible, separated, through which a cooling medium flows completely as it enters and exits. The lamella ensures that the module is completely flushed through, only allowing backflow or reversal of the flow at the end. If an extruded profile with integrated cooling fins is used as the base body, the fin is only pushed in two optimally opposite cooling fins. One or more 'stoppers' prevent this 'Lowering' the slat, ie holding the slat in position. Alternatively, the length of the slat corresponds to the inner length of the module and it has at least one opening for flow. An optimal flow (fluid mechanics) can be determined through calculations or simulations with several breakthroughs.

Alternatively, at least one slat made of sheet metal, for example, can be fixed on the cover next to one of the two connections. This is designed so that the inlet or outlet is not covered. When combined, the slats form three separate sections that are as large as possible, through which a cooling medium flows completely as it enters and exits. The slats ensure that the module is completely flushed. If an extruded profile with integrated cooling fins is used as the base body, the fin is pushed into two cooling fins. If the cooling fins are oriented towards the center as shown here, the lamella can be curved or bendable or have the corresponding contour to create the above-mentioned sections.

Two modules can be connected in parallel next to each other, i.e. combined, to cool two potentials with one unit. An insulator between the modules is designed so that it seals and fixes the modules, but also acts as an insulator.

Foils, gap fillers and spacers, individually or in combination, are used for galvanic isolation. In a preferred embodiment, a film made of polyimide with an elastic cover layer is used. Due to the high dielectric strength of polyimide (approx. 150 to 200 kV/mm), insulation can be guaranteed with a wall thickness of approximately 25 to 40 µm. The elastic cover layer is approx. 0.5 to 1.5 mm thick and preferably consists of silicone with ceramic fillers. This allows an ideal compromise between elasticity and thermal conductivity to be achieved. The film encloses the entire surface of the module and ensures that the requirements for high-voltage-low-voltage separation are met.

The film can have a printed or fully or partially integrated temperature sensor system. Alternatively, the sensor system can also be integrated into the spacer, whereby conventional sensor components (SMD) can also be used here. The system can be monitored directly using sensors.

The spacer, here part of the cap, ensures that the gap filler is not displaced by the DC bar busbar and thus ensures the necessary distance. The contour of the spacer is designed so that the gap filler is pressed between the spacer and the film for assembly.

The electrical insulation consisting of foil, gap filler and spacer can also be used for cubic shapes.

The module can be as in 4 be covered by the DC bar (= busbar). The lateral surface (M) can essentially be an open >180° semicircle and fix the body in place so that the rail briefly gives way during installation. The module can be clipped into the DC bar.

The module can be as in 6 can also be completely enclosed by a second element of the rail. The second element is connected to the DC bar, for example by welding, screwing, riveting, etc.

The module can be as in 7 be fixed by one or more additional holding elements. The holding element is optimally made from a material with optimized thermal conductivity, for example thermally conductive plastic.

The DC bar can use the module as in 5 Enclose it so that it is fixed. The DC bar can, for example, have a tab at the end with which the end is fixed to itself elsewhere. The DC bar may have local weakenings such as beads, notches and/or notches to allow local movement when installing the module.

The holding element can hold the cell as in 8th also fully enclose and thus fully take over the heat conduction and fixation. The galvanic isolation from the DC bar is therefore provided directly.

The module can also be oriented laterally. This variant allows two cooling modules to be directly coupled to the other DC pin or the other potential. The arrangement has the advantage that the DC bar “holds” the module by forming a depression.

The cooling module can be as in 10 Alternatively, they should not be “contacted” on the outer surface, but rather be thermally coupled via the end surface, ie via the caps of the cooling unit. The fixation takes place, for example, using screws, circumferential welding or clips.

The inlet and outlet can be positioned on both sides, in which case the DC bar requires the necessary recesses for the inlet and outlet. The front side is contacted directly at potential or galvanically separated by spacers, gap fillers, etc.

A flat, elongated cooling unit can be used as in 9 can be placed directly on the DC bar. A holder is designed in such a way that it represents the spacer and the filling area for the gap filler all around. Lateral tabs in the direction of the DC bar maintain the creepage distances. The holder is fixed to the housing or other components.

A cap is designed to hold the cooling unit in position and ensure even contact pressure on the rail. The cap is clipped, screwed or welded to the holder, for example.

The cooling module can be as in 10 fully integrated, i.e. proportionally connected to the DC bar and sealed. The material bond is achieved, for example, by friction or laser welding. Other processes are possible depending on the design and material pairing. The cooling module can be integrated frontally or from the front. Alternatively, the cooling module can be integrated on the back. The connections can be on the back or through the DC bar itself. It is possible to press in, weld or screw the inlet or return. Slats can be integrated on the DC bar and/or in the cooling module.

The cooling module can be as in 11 can also be proportionately enclosed and fixed by two DC bars at different potentials. The DC bars surround the module in such a way that the creepage distances are maintained. This type of integration reduces EMC emissions.

The cooling module can be as in 14 also be oriented horizontally or transversely. The two potentials do not encompass the module completely and symmetrically. The DC bars can be stacked for EMC optimization. The outputs of the DC bars can also be located next to each other to optimize the connection.

Since the devices and methods described in detail above are exemplary embodiments, they can be modified to a wide extent in the usual way by those skilled in the art without departing from the scope of the invention. In particular, the mechanical arrangements and the size ratios of the individual elements to one another are merely examples.

REFERENCE SYMBOL LIST

100

busbar

102

Recording

104

cold room

106

Connection panel

108

Pin code

110

interface

112

High-voltage distribution system

114

tab

116

Lateral surface

118

Connection

200

gap

202

Spacer

204

foil

206

Wall

208

inner space

210

rib

212

lamella

214

Sub-area

300

Heat storage medium

302

Filling height

304

Noble gas

306

Phase change material

308

Lid

310

Compensating opening

500

flange

502

Bending area

600

Holding element

700

thickening

800

Foot

900

recess

1000

Floor

1100

Pair of busbars

1102

Touch protection cap

1104

Touch protection collar

1200

Subcell

1202

insulator

1204

Overflow channel

1206

Flow path

Claims (10)

Busbar (100), wherein the busbar (100) forms a receptacle (102) for a cooling cell (104) and the cooling cell (104) is arranged in the receptacle (102), the receptacle (102) being designed to hold the cooling cell (104) to be thermally coupled to the busbar (100), the cooling cell (104) having connections (118) for a cooling system dium and is designed to actively control the temperature of the busbar (100). Busbar (100) according to Claim 1 , in which the cooling cell (104) has ribs (210) aligned with an interior (208) of the cooling cell (100). Busbar (100) according to one of the preceding claims, in which the cooling cell (104) has at least one lamella (212) running through an interior (208) of the cooling cell (104). Busbar (100) according to Claim 2 and Claim 3 , in which the at least one slat (212) is held by the ribs (210). Busbar (100) according to one of the preceding claims, in which the at least one lamella (212) forms a flow path (1206) for the cooling medium in the interior (208). Busbar (100) according to Claim 5 , in which the at least one lamella (212) has flow openings for the cooling medium. Busbar (100) according to Claim 5 , in which the at least one lamella (212) is shorter than the interior (208) in order to form the flow path (1206) for the cooling medium. Busbar (100) according to one of Claims 3 until 7 , in which the cooling cell (104) has at least two slats (212) in the interior (208), the slats (212) protruding into the interior (208) from opposite sides. Busbar (100) according to one of the preceding claims, in which the busbar (100) forms at least one wall (206) of the cooling cell (104) in the area of the receptacle (102). Busbar (100) according to Claim 9 , in which connections (118) of the cooling cell (104) run through the busbar (100).

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