Cooled Busbars for Power Distribution

Abstract

A cooling busbar for power distribution, particularly for electric vehicles, is disclosed. The cooling busbar includes one or more conductive layers and one or more hollow portions (228). A cooling medium, such as a liquid coolant, can flow through the hollow portions. The cooling busbar includes a rigid conductor (223), an insulating layer (224), and a shielding layer (225).

Description

[Technical field]

[0001] [CROSS REFERENCE TO RELATED APPLICATIONS] This application is a nonprovisional application claiming priority to U.S. Provisional Patent Application No. 63 / 263,322, entitled "COOLED BUSBAR FOR ELECTRIC VEHICLE POWER DISTRIBUTION," filed on October 29, 2021, which is incorporated by reference in its entirety and for all purposes.

[0002] The disclosed technology relates to power distribution and, more particularly, to power distribution in electric vehicles. [Background technology]

[0003] Charging systems for electrical systems, such as electric vehicles or any electrical system that involves power transmission from one or more power sources to one or more loads, can utilize flexible braided cables to conduct electricity from the power source to the power load. For example, power can be transmitted from a vehicle charging inlet (e.g., power source) to a vehicle battery (e.g., power load). These cable systems can provide high voltage and high current carrying capacity for high charging rates. These cables are typically flexible and include braided metal encapsulated by single or multiple layers of insulation and metal sleeves for contact safety and electromagnetic compatibility (EMC) shielding. As the need for power charging rates (e.g., charging rates for electric vehicles) increases, the use of flexible braided cables can present technical challenges. Summary of the Invention

[0004] Each claimed innovation has several aspects, no single one of which is solely responsible for its desirable attributes. Without limiting the scope of the claims, some prominent features of the disclosure will now be briefly discussed.

[0005] One aspect of the present disclosure is a power distribution system that includes a bus bar that includes a rigid conductor configured to carry electrical current from a power source to a load, a hollow portion configured to allow a cooling medium to flow therethrough, an insulating layer, and a shielding layer.

[0006] The rigid conductor may include at least one of aluminum or copper. The hollow portion may be surrounded by the rigid conductor. The insulating layer may provide electrical insulation. The insulating layer may further include at least one of cross-linked polyethylene (XLPE), polyvinyl chloride (PVC), nylon, silicone, thermoplastic, or thermoset plastic. The shielding layer may be electrically conductive. The insulating layer may also be disposed between the rigid conductor and the shielding layer.

[0007] The busbar in the power distribution system can include an inner tube layer and an electrical insulation layer. The electrical insulation layer is disposed between the inner diameter of the rigid conductor and the inner tube layer. The hollow portion can surround the outside of the outer diameter of the rigid conductor.

[0008] The rigid conductor may further include a first end and a second end, each of the first end and the second end having an electrical contact area.

[0009] The power distribution system may further include a coolant source, where a cooling medium flows from the coolant source to the busbar and from the second busbar to the coolant source.

[0010] The power distribution system may further include a U-loop adapter connected to the bus bar and to a second bus bar, the second bus bar configured to provide a return flow of the cooling medium.

[0011] The power distribution system may further include a reservoir and a pump configured together to supply a cooling medium to the hollow portion of the busbar.

[0012] The power distribution system may further include a charge port connection unit configured to connect the busbar to a power source.

[0013] Another aspect of the disclosure is an electric vehicle including a battery, a charge port, and a bus bar. The bus bar can include a rigid conductor configured to carry electrical current in an electrical path from the charge port to the battery, a hollow portion configured for a cooling medium to flow therethrough, an insulating layer, and a shielding layer.

[0014] Another aspect of the disclosure is a busbar including a conductor configured to carry electrical energy between components of an electric powertrain and a conduit for a cooling medium, the conductor and the conduit both being part of a single busbar assembly, the busbar being a rigid busbar.

[0015] The cooling medium may include a liquid coolant.

[0016] The busbar may further include a second conduit.

[0017] The bus bar may further include a second conductor and an insulating layer, the insulating layer being disposed between the conductor and the second conductor.

[0018] The conductors of the busbars may include at least one of aluminum or copper.

[0019] The busbar may further include a shielding layer surrounding the conductor. The busbar may further include an insulating layer disposed between the conductor and the shielding layer.

[0020] The conduits of the busbar can include an electrical insulation layer configured to electrically insulate the conductors from the coolant flowing through the conduits. The electrical insulation layer can include at least one of polyethylene, nylon, polyvinyl chloride, silicone thermoplastic, or thermoset plastic.

[0021] Another aspect of the disclosure is an electric vehicle that includes a first liquid-cooled component configured to store electric energy, a second liquid-cooled component configured to utilize the electric energy, and a busbar in a path between the first liquid-cooled component and the second liquid-cooled component, the busbar comprising a rigid conductor configured to carry the electric energy and a conduit configured to carry a liquid coolant between the first liquid-cooled component and the second liquid-cooled component.

[0022] For purposes of summarizing the present disclosure, certain aspects, advantages, and novel features of the innovation are described herein. It should be understood that not all such advantages may be achieved according to any particular embodiment. Thus, the innovation may be embodied or implemented to achieve or optimize one advantage or group of advantages as taught herein, without necessarily achieving other advantages as may be taught or suggested herein. [Brief description of the drawings]

[0023] Embodiments of the present disclosure will now be described, by way of non-limiting examples, with reference to the accompanying drawings, in which:

[0024] [Figure 1] FIG. 1 illustrates an embodiment of a charging system including a pair of cooling bus bars.

[0025] [Figure 2A] FIG. 2 is a diagram showing a pair of cooling bus bars.

[0026] [Figure 2B] FIG. 2 is a cross-sectional view of a cooling busbar including an inner tube layer, a rigid conductor, and a first electrically insulating layer according to one embodiment.

[0027] [Figure 2C] FIG. 2 is a cross-sectional view of a cooling busbar including an inner tube layer, a rigid conductor, a first insulation layer, and a second insulation layer according to one embodiment.

[0028] [Figure 2D] FIG. 2 is a cross-sectional view of a cooling busbar including an inner tube layer, a rigid conductor, a first insulating layer, a second insulating layer, a shielding layer, and a color layer according to one embodiment.

[0029] [Figure 2E] FIG. 1 illustrates a perspective view of a cooling busbar having electrical contact areas and an insulating layer on an inner diameter of a rigid conductor according to one embodiment.

[0030] [Figure 2F] FIG. 1 is a side cross-sectional view of a cooling busbar having electrical contact areas and an insulating layer on the inner diameter of the rigid conductor and an inner tube layer on the inner diameter of the insulating layer.

[0031] [Figure 3A] FIG. 2 is a perspective view of an end portion of a charging port connection unit and a pair of cooling bus bars.

[0032] [Figure 3B] FIG. 1 illustrates a perspective view of a U-loop adapter connected to a cooling busbar, according to one embodiment.

[0033] [Figure 3C] FIG. 13 is another see-through view of a U-loop adapter connected to a cooling bus bar according to one embodiment.

[0034] [Figure 4A] FIG. 2 is a perspective view of one embodiment of a load connection unit and an end of a pair of cooling bus bars.

[0035] [Figure 4B] FIG. 4B is a perspective view of one embodiment of a pair of cooling bus bars coupled to the load connection unit of FIG. 4A.

[0036] [Figure 4C] FIG. 4B is a cross-sectional view showing a pair of cooling bus bars coupled to the load connection unit of FIG. 4A.

[0037] [Figure 5A]FIG. 2 is a perspective view of a pair of cooling bus bars connected to a load.

[0038] [Figure 5B] FIG. 2 is a perspective view of an embodiment of a pair of cooling bus bars.

[0039] [Figure 6] FIG. 1 is a diagram of an electric vehicle power and coolant distribution system using cooling busbars, according to one embodiment.

[0040] [Figure 7] FIG. 2 is a cross-sectional layered view of an exemplary embodiment of a multi-layer cooling busbar including two flat sides.

[0041] [Figure 8] FIG. 2 is a cross-sectional layered view of an exemplary embodiment of a multi-layer cooling busbar including layers of electrically conductive coolant tubes.

[0042] [Figure 9] FIG. 2 is a cross-sectional layered view of an exemplary embodiment of a multi-layer cooling busbar including multiple conductive layers.

[0043] [Figure 10] FIG. 1 is a cross-sectional layered view of an exemplary embodiment of a multi-layer cooling busbar in which multiple coolant flows have two or more coolant flow directions.

[0044] [Figure 11] FIG. 2 is a cross-sectional layered view of an exemplary embodiment of a multi-layer cooling busbar having a circular cross-section including multiple conductors and coolant channels.

[0045] [Figure 12] FIG. 2 is a cross-sectional layered view of an exemplary embodiment of a multi-layer cooling busbar including multiple conductors and a single coolant channel.

[0046] [Figure 13A] 1A is a cross-sectional view of an example embodiment of a busbar having two or more hollow portions about an inner rigid conductor.

[0047] [Figure 13B] 1 is a perspective view of an example embodiment of a busbar implementing one or more hollow portions around an inner rigid conductor;

[0048] [Figure 14] FIG. 1 illustrates a perspective view of an example embodiment of a busbar having a rectangular shape with a plurality of inner rigid conductors and a plurality of hollow portions surrounding the inner rigid conductors. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0049] The following detailed description of certain embodiments presents various descriptions of certain embodiments. However, the innovations described herein may be embodied in many different ways, for example, as defined and encompassed by the claims. This description refers to the drawings, in which reference numbers may indicate identical or functionally similar elements. It will be understood that the elements depicted in the drawings are not necessarily drawn to scale. Furthermore, it will be understood that certain embodiments may include more elements than are depicted in the drawings and / or a subset of the depicted elements. Furthermore, some embodiments may incorporate any suitable combination of features from two or more drawings.

[0050] As discussed above, flexible stranded wires for conducting electricity in electrical systems or components, such as electric vehicles, may face technical challenges as demands for charging rates (e.g., charging rates for electric vehicles) increase. The busbars disclosed herein may be implemented in electric vehicles or any other suitable power distribution system. Although the embodiments disclosed herein may be described with reference to electric vehicles for illustrative purposes, any suitable principles and advantages disclosed herein may be implemented in any suitable power supply system.

[0051] As demand for electric vehicles with faster charging rates increases, cables with larger cross-sectional areas may be desirable, however, increasing the cable cross-sectional area may result in higher costs in one or more of raw materials, transportation and logistics constraints, vehicle packaging constraints, heat losses, and loss of vehicle range due to increased mass.

[0052] SUMMARY OF THE DISCLOSURE Embodiments of the present disclosure relate to a cooling busbar for a power distribution system, such as an electric vehicle power distribution system. The cooling busbar can carry high voltages. The cooling busbar can be shielded. The cooling busbar can distribute both power and liquid / coolant within the electric vehicle.

[0053] For example, the cooling busbar may include one or more conductors and a coolant that extend from a point, such as a power source (e.g., a power supply) to another point, such as a power load (e.g., a motor). In this example, the conductors may provide power from a power source, such as a battery, to a power load, such as a motor, and the coolant may also flow between the power source and the load. Further, in this example, the coolant may be a coolant liquid that may cool the conductors when the temperature of the conductors increases due to high power transmission in the conductors. Thus, the cooling busbar may transmit high power from the power source to the load. The power source is not limited to any particular power source, and the power source may include any suitable unit that provides power to one or more electrical components in an electrical system, such as an electric vehicle.

[0054] In one embodiment, a pair of cooling bus bars transfers power from a charging port of an electric vehicle to a battery pack. The cooling bus bar pair can extend from the charging port to the battery pack. In some embodiments, the cooling bus bar distributes power from the battery pack to one or more electrical components in the vehicle. The cooling bus bar can distribute power from the battery pack to a power conversion system (PCS) and drive unit of an electric vehicle in certain applications. In such applications, the cooling bus bar pair can extend from the battery pack to the front and / or rear drive units. In one embodiment, the battery pack, PCS, and drive unit are connected via a pair of cooling bus bars. In this embodiment, the pair of cooling bus bars can distribute power from the battery pack to the PCS and drive unit while circulating coolant from a coolant reservoir to the battery pack, PCS, and drive unit. The cooling bus bars disclosed herein can be used in any suitable electrical system involving power distribution.

[0055] The cooled busbar can provide at least an order of magnitude increase in system capacity in the same packaging volume compared to cable harnesses or solid core busbars. The cooled busbar can support high charging rates such as 350 kW charging at 400V or 500 kW charging at 800V. Maintaining the temperature of the busbar below the temperature limit of the busbar material can contribute to achieving such high charging rates. With the cooled busbar, faster charging times can be achieved than with certain other busbars, and faster charging times can be achieved at lower temperatures. The cooled busbar can contribute to faster charging, higher throughput at the charging station, and lower system costs. The cooled busbar can include liquid as its cooling medium. Furthermore, the cooled busbar can transmit both power and liquid. As such, it can eliminate some of the thermal lines of traditional electric vehicles that are separate from the charging lines.

[0056] In some embodiments, the cooling busbar includes a rigid conductor and an inner tube layer. An electrical insulation layer can surround the rigid conductor. In some embodiments, the material of the rigid conductor can include any suitable conductive material, such as aluminum, copper, bronze, brass, gold, silver, etc., or any suitable combination or alloy thereof. The rigid conductor can include one or more hollow portions. Such hollow portions of the rigid conductor can be fitted onto the inner tube layer to allow for the passage of a cooling medium for active and / or passive cooling. In one embodiment, the cooling medium can be a liquid coolant. In one embodiment, the cooling medium can be passive cooling using a phase change material, such as hydrated salts or paraffin wax. In one embodiment, the cooling medium is made of a dielectric material. For example, a dielectric material can be included inside the hollow portion of the rigid conductor and the inner tube can be eliminated. The cooling medium can be air in some cases. Any suitable material can be utilized as the cooling medium of the cooling busbar for a particular application.

[0057] In some embodiments, power is distributed through the rigid conductors and liquid is distributed through the inner tube layer. In these embodiments, the cooling busbar distributes both power and coolant, so that the power cables and thermal hoses from some other electric vehicles can be replaced with a single cooling busbar. During power transmission, the liquid can flow through the inner tube layer, maintaining the temperature of the rigid conductors below the temperature limit of the busbar (e.g., the cooling busbar). Thus, high power can be transmitted without increasing the cross-sectional area of ​​the rigid conductors. In some embodiments, the liquid can be supplied from a liquid reservoir of the vehicle, such as a coolant reservoir. Such a reservoir can be a dedicated reservoir for the busbar. Alternatively, the liquid reservoir can be used for another purpose, such as cooling a battery or another component of the electric vehicle. Such a shared reservoir can have a dedicated port for interfacing with the cooling busbar. Alternatively or additionally, the liquid can be supplied from a radiator of the vehicle, which cools the liquid. A pump can flow the liquid from the liquid source through a channel defined by one or more hollow portions of the busbar. Examples of liquids include, but are not limited to, water, oil, and other liquids or solutions. The liquid may be selected based on its thermal conductivity or heat capacity.

[0058] In some embodiments, an electrical insulation layer may be lined between the inner tube layer and the rigid conductor. The inner tube layer may be electrically insulating and thermally conductive. The inner tube layer may be made of any suitable thermally conductive material, such as aluminum. In one embodiment, the inner tube layer is made of a non-conductive material, such as a thermoplastic or thermoset plastic. In one embodiment, the inner tube layer is a coating layer on the inner diameter of the rigid conductor.

[0059] The insulated rigid conductor may be surrounded by a shielding layer. The shielding layer provides shielding against electromagnetic interference (EMI) and protection from damage to the cooling busbar. The shielding layer may be flexible or rigid. If the shielding layer is rigid, it may physically protect the insulation layer from external conditions and / or damage during the 3D bending process. The shielding layer may be made of any suitable EMI shielding material, such as aluminum, conductive plastic, carbon fiber, stainless steel fiber, etc. In some embodiments, the shielding layer may be grounded to the vehicle's body-in-white (BIW). This allows for detection of insulation loss in the event of a high voltage short circuit.

[0060] In some embodiments, various cross-sectional shapes of the rigid conductors can enhance and / or optimize liquid flow and increase and / or maximize power transfer rates. In one embodiment, the rigid conductors have a circular cross-section and a circular hollow portion, which fits into the inner tube layer.

[0061] In some embodiments, the electrical insulation layer may be made of any electrically insulating material such as cross-linked polyethylene (XLPE), PVC, silicone, or plastic, etc. In one embodiment, the electrical insulation layer may be applied by an assembly method such as a heat shrink or extrusion process.

[0062] In some embodiments, two or more cooling busbars run together (e.g., in parallel) with another cooling busbar to transfer relatively high power. Although embodiments may be described with two cooling busbars for illustrative purposes, any suitable principles and advantages disclosed herein may be applied to applications with three or more cooling busbars and / or applications with a single cooling busbar. In one embodiment, a parallel cooling busbar may run from a charging inlet of an electric vehicle to a connection unit in a battery pack. In this embodiment, the connection unit includes a liquid supply port and a return port. For example, a pump at or near the connection unit may supply liquid to an inner tube layer of one of the parallel cooling busbars. The liquid then flows into the inner tube layer of another cooling busbar and returns to a liquid reservoir at or near the connection unit.

[0063] The technology disclosed herein can be applied to a variety of applications. For example, in addition to cooling conductors using a coolant, the busbars disclosed herein can carry coolant between different parts and / or components of an electric vehicle. This can eliminate parallel routing of power distribution and coolant. As another example, multiple conductors and / or multiple fluid conduits can be included in a single busbar.

[0064] FIG. 1 illustrates a high power transmission system 100 of an embodiment of high power transmission using a pair of cooling bus bars 200. The cooling bus bars 200 can be implemented in an electric vehicle, such as a car, a sport utility vehicle, a truck, or any other electric vehicle. The pair of cooling bus bars 200 includes first and second cooling bus bars 201, 202. The cooling bus bars 201, 202 include electrical conductors on which power is concentrated for distribution in an electronic power distribution system, such as an electric vehicle. The cooling bus bars 201, 202 are rigid and retain their shape. With rigid cooling bus bars 201, 202, routing brackets and clips may not be required. In a factory assembly environment, assembly with rigid cooling bus bars 201, 202 may be easier compared to flexible harnesses. The cooling bus bars 201, 202 can carry direct current (DC) power, alternating current (AC) power, or AC and DC power. The raw material for the cooling busbars 201, 202 can be densely packaged and shipped directly from the supplier to the installation site so that it can be bent to fit the on-board packaging, eliminating the need for handling the cables and connectors from some previous busbars.

[0065] 1, a pair of cooling bus bars 200 connect a charging port connection unit 300 and a connection unit 400, which is connected to a load such as a battery pack. The connection unit 400 is an example of a load connection unit that connects a bus bar to a load. The length and path of the cooling bus bars 201, 202 may be determined based on the design or curvature of the underbody of the vehicle and the location of the power source and the load within the vehicle.

[0066] FIG. 2A illustrates a pair of cooling bus bars 200. As illustrated, the pair of bus bars 200 includes a power end 230 and a load end 220. In FIG. 2A, the power end 230 and the load end 220 are disposed toward a power source and a load, respectively. The locations of the load end 220 and the power end 230 can be selected based on physical attributes of the vehicle, such as the location of the power source and the load. For example, the load end 220 can be disposed in one direction toward a load, such as a battery in an electric vehicle. The power end 230 can be disposed in the opposite direction toward a power source, such as an electric vehicle charging port.

[0067] 2B-2D show cross-sectional views of various embodiments of the cooling busbar 201. In some embodiments, for example as shown in FIG. 2B, the cooling busbar 201 comprises a rigid conductor 223 and an inner tube layer 221, with a first electrical insulation layer 224 surrounding the rigid conductor 223. The rigid conductor 223 further comprises one or more hollow portions 228. In FIG. 2B, the hollow portions 228 are fitted inside the surface of the inner tube layer 221 and allow a cooling medium to pass through for active or passive cooling. The hollow portions 228 can function as tubes for liquid coolant to flow through. The rigid nature of the busbar 201 can provide a rigid channel for the liquid coolant flow. In some embodiments, the inner tube layer 221 can be made of a thermally conductive material such as aluminum. The rigid conductor 223 can be made of any suitable electrically conductive material such as aluminum or copper.

[0068] In some embodiments, for example as shown in FIG 2C, in addition to the embodiment described in FIG 2B, a second insulating layer 222 can be included between the inner tube layer 221 and the rigid conductor 223. As shown in FIG 2C, the second insulating layer 222 can provide electrical insulation between the inner tube layer 221 and the rigid conductor 223.

[0069] In some embodiments, the rigid conductor 223 is surrounded by a shielding layer 225, as shown, for example, in FIG. 2D. The shielding layer 225 can provide a shield against electromagnetic interference. Such a shield can protect the rigid conductor 223 from damage. The shielding layer 225 can be flexible or rigid. The shielding layer 225 can be made of any suitable EMI shielding material, such as aluminum. In some embodiments, the shielding layer 225 can physically protect the insulation layer from external conditions and / or damage during a manufacturing process, such as a 3D bending process. In some embodiments, the shielding layer 225 can be grounded to the vehicle's body-in-white (BIW). This allows for detection of insulation loss in the event of a high voltage short circuit. The shielding layer 225 can be surrounded by a coloring layer 226. The coloring layer 226 can provide a specific color to each cooling busbar, so that each cooling busbar can be differentiated from other cooling busbars based on the color of the coloring layer 226.

[0070] In the illustrated embodiment, as shown in Figures 2B-2D, the inner tube layer 221 may be made of any suitable thermally conductive material, such as aluminum. The rigid conductor 223 may be made of any suitable electrically conductive material, such as aluminum or copper. The first and second insulating layers 224, 222 may each be made of any suitable electrically insulating material, such as XLPE, PVC, nylon, silicone, or plastic. In one embodiment, the first and second insulating layers 224, 222 may be applied by an assembly method, such as a heat shrink, extrusion, or coating process. The shielding layer 225 may be flexible or rigid and may be made of any suitable EMI shielding material, such as aluminum or any suitable electrically conductive material, including EMI plastic. The colored layer 226 of Figure 2D may be made of any suitable electrically insulating material with any suitable color coating. A liquid 227 may be present in the hollow portion 228 of the busbar. The liquid 227 may be selected based on its thermal conductivity or heat capacity. Examples of liquid 227 include, but are not limited to, water, oil, and other liquids and / or solutions for cooling. Any other suitable cooling medium may be used in place of liquid 227, such as air, a solid, or a phase change material, such as a hydrated salt or paraffin wax.

[0071] In some embodiments, various cross-sectional shapes of the rigid conductor 223 can be used to enhance and / or maximize the power transfer rate. For example, the rigid conductor 223 may have a rectangular cross-sectional shape. In some embodiments, the rigid conductor 223 may have two or more hollow sections to increase and / or optimize the flow of the liquid 227. In this embodiment, the hollow sections can also be used to achieve bidirectional flow.

[0072] 2E and 2F show the electrical contact areas 206 of the busbars. In the illustrated embodiment, the ends of the first and second cooling busbars 201, 202 each have an electrical contact area 206. In these embodiments, the rigid conductors 223 are exposed, with the exposed surfaces of the rigid conductors 223 forming the electrical contact areas 206. The electrical contact areas 206 at both ends of the cooling busbars 201, 202 are coupled with appropriate positive and negative terminals of the charging port connection units 300 and 400. In various applications, any suitable end connection unit for transmitting power can be used in place of the charging port connection unit 300. The busbar of FIG. 2E includes an insulating layer 222 on the inner diameter of the rigid conductors 223. The busbar of FIG. 2F includes an insulating layer 22 on the inner diameter of the rigid conductors 223 and an inner tube layer 221 on the inner diameter of the insulating layer 222. The inner tube layer 221 can provide protection from corrosive fluid media and the like.

[0073] The cooling busbars disclosed herein can be connected to a variety of connection units for connecting to a power source and connecting to a load. The cooling busbars can be compatible with connection units for other busbars in certain applications. Thus, the cooling busbars disclosed herein can be backward compatible with a variety of connection units and charging ports.

[0074] FIG. 3A illustrates a charge port connection unit 300 and an end of a cooling busbar, such as the power supply end 230. As illustrated, the charge port connection unit 300 has a U-loop adapter 320 mounted to a charge port 310 configured to receive electrical power. The first busbar end 203 and the second busbar end 204 can be connected to the U-loop adapter 320. For example, as shown in FIG. 3A, the electrical contact area 206 of the power supply end 230 can be inserted into the U-loop adapter 320. The U-loop adapter 320 includes a U-loop 311, which in turn includes a first U-loop arm 312 and a second U-loop arm 313. The U-loop adapter 320 can include canted coil springs 314, each of which can be connected to the first and second U-loop arms 312, 313 and can be configured to surround one of the electrical contact areas 206.

[0075] 3B and 3C show diagrams of a U-loop adapter 320. As shown, the first busbar end 203 and the second busbar end 204 are molded in parallel on the inside of the U-loop adapter 320. In one embodiment, the first busbar end 203 is connected to the first U-loop arm 312 and the second busbar end 204 is connected to the second U-loop arm 313. The connection between the first and second busbar ends 203, 204 and the U-loop 311 can be changed based on the application. As shown in FIG. 3B, the U-loop adapter 320 can include a first forged terminal 236. The U-loop adapter 320 can also include a second forged terminal (not shown in FIG. 3B). One end of the first and second forged terminals can be molded into the U-loop adapter 320. The other end of the forged terminal can be connected to a charging port terminal. An electric vehicle can receive power from an external power source, such as a charging station, via the charging port terminal. The electrical contact areas 206 of the first and second busbar ends 203, 204 shown in FIG. 3A may be coupled to forged terminals 236 and surrounded by canted coil springs 314. The diameter of the first and second U-loop arms 312, 313 may be smaller than the inner tube diameter of the first and second busbar ends 203, 204. The loops of the U-loop adapter 320 may provide return flow when one busbar is used to supply coolant and the other busbar is used to return coolant. In some other embodiments without a U-flow, the coolant may continue elsewhere after traveling to the power source or load.

[0076] FIG 4A shows a load connection unit and the ends of a pair of cooling bus bars. The load connection unit is shown in FIG 4A as connection unit 400. The illustrated connection unit 400 has a header 403, a connection insulator 406, a first plug 401 and a second plug 402. In FIG 4A, the first bus bar head 251 and the second bus bar head 252 each have an electrical contact area 206. The connection unit 400 and the U-loop adapter 320 of FIG 3A and FIG 3B can be connected to the opposing ends of the cooling bus bars.

[0077] 4B illustrates an embodiment in which first and second cooling busbars 201, 202 are coupled to a connection unit 400. The electrical contact area 206 of the first busbar head 251 is coupled to a first plug 401. The electrical contact area 206 of the second busbar head 252 is coupled to a second plug 402. The connections between the first and second busbar heads 251, 252 and the first and second plugs 401, 402 can vary depending on the application.

[0078] 4C shows a cross section of a connection unit 400 coupled to cooling busbars 201, 202. In the illustrated embodiment, the first busbar head 251 is coupled to a first mounting member 408 and the second busbar head 252 is connected to a second mounting member 409. This embodiment also shows that the electrical contact areas 206 of the first and second busbar heads 251, 252 are coupled to first and second plugs 401, 402. In one embodiment, one end of the first and second plugs 401, 402 plug into a DC terminal of a battery pack and the other end of the first and second plugs 401, 402 are molded inside a back cap 407. In this embodiment, the first and second busbar heads 251, 252 can be inserted into the first and second liquid headers 404, 405 such that the electrical contact areas 206 of the first and second busbar heads 251, 252 can contact the first and second plugs 401, 402. The connection unit 400 can provide a passageway for the cooling busbars 201, 202. The connection unit 400 can split the cooling medium from the current carrying electrical contact areas 206 on the cooling busbars 201, 202 to the plugs 401, 402.

[0079] 5A and 5B show a pair of cooling busbars 201, 202 connected to a load. In some embodiments, liquid can be circulated within the cooling busbars 201, 202 by receiving liquid from a liquid source, such as a liquid reservoir, as shown in FIG. 5A. For example, the pair of cooling busbars 201, 202 can be connected to a liquid reservoir via liquid pipelines 501, 502, such that liquid can be supplied to one of the pair of cooling busbars 201, 202 and circulated within the cooling busbars 201, 202. FIG. 5B shows one embodiment of liquid circulation. In one example, liquid may be supplied from the first mounting member 408 of the connection unit 400 shown in FIG. 4C, circulated through the first cooling busbar 201, the U-loop 311 shown in FIGS. 3A-3C, and the second cooling busbar 202, and returned to the second mounting member 409 of the connection unit 400 shown in FIG. 4C. In other embodiments, liquid may be provided from the second mounting member 409 and returned to the first mounting member 408. The direction of circulation of the liquid 227 may be based on the geometry of the electric vehicle.

[0080] FIG. 6 illustrates an example of a power and coolant distribution system 600 that uses a pair of cooling bus bars 200. As illustrated, the pair of cooling bus bars 200 can distribute power and circulate liquid between components. For example, in an electric vehicle, the pair of cooling bus bars 200 can extend from a battery pack 604 to a forward drive unit 601, a rear drive unit 602, and a power conversion system (PCS) 603 of the electric vehicle. The cooling bus bars 200 distribute power and circulate coolant. In the power and coolant distribution system 600, no separate coolant hoses are included next to the pair of cooling bus bars 200. This can eliminate the need for parallel coolant lines from certain previous designs. The diagram illustrated in FIG. 6 is provided for illustrative purposes only, and the present disclosure is not limited to electric vehicle power distribution systems, and any suitable principles and advantages of the power distribution system of FIG. 6 can be applied to any other suitable power distribution system.

[0081] SUMMARY OF THE DISCLOSURE Embodiments of the present disclosure relate to busbars for distribution of electrical energy and coolant between components of an electric vehicle. In many existing electric vehicles, multiple liquid-cooled components that utilize and / or store electrical energy are distributed throughout the vehicle. Examples of such components include, but are not limited to, battery packs, power conversion and / or distribution boxes, inverters, motors, etc. Traditionally, these components utilized separate inputs and outputs for coolant and electrical energy, resulting in parallel flow of power and coolant between each element of the powertrain.

[0082] By combining the conduits for distributing electrical energy and coolant into a single assembly, thermodynamic busbars enable more efficient, smaller, and less expensive powertrains. Cooling busbars can connect static components and / or can connect dynamic components, such as drive units.

[0083] The core of the cooling busbar may be an insulated coolant conduit. The insulated coolant conduit may be a homogenous insulating material (e.g., nylon, polyethylene (PE), cross-linked polyethylene (XPLE), polyvinyl chloride (PVC), silicone, etc.). The homogenous insulating material may be formed by any suitable process, such as extrusion, injection molding, blow molding, etc. In some other applications, the insulated coolant conductor may include an electrically conductive material (e.g., aluminum, copper, etc.) with an electrically insulating (e.g., nylon, PE, XPLE, PVC, silicone, etc.) outer coating. The outer coating may be formed by any suitable process, such as powder coating, dip coating, forming a sleeve, heat shrinking, co-extrusion, etc.

[0084] The coolant conduits may serve the dual purpose of carrying coolant between a source and a destination and absorbing a portion of the heat generated by the flow of electrical energy within the outer conductive layer of the busbar.

[0085] The coolant conduit may include a single or multiple sealed volumes and may carry coolant in one or both directions. The coolant conduit is surrounded by a conductive layer (e.g., aluminum, copper) that carries electrical energy from a power source to a load. The coolant conduit may include any suitable cooling medium, such as liquid coolant, air, a phase change material (e.g., hydrated salt or paraffin wax). The conductive layer may be implemented according to any suitable principles and advantages of the rigid conductors disclosed herein. An insulating layer (e.g., nylon, PE, silicone) may be around the conductive layer. The insulating layer may be assembled by any suitable method, such as heat shrinking, co-extrusion, extrusion and bonding, injection molding, etc. Depending on the number of desired electrical paths between the ends of the busbar, additional conductive and insulating layers may be included around the inner conductive and insulating layers of the cooling busbar. An outer conductive layer (e.g., aluminum, copper, conductive thermoplastic) may be included outside of one or more primary conductive paths to act as an electromagnetic shielding layer. The outer conductive layer may also act as a physical and environmental barrier. The outer conductive layer may be implemented according to any suitable principles and advantages of the shielding layers disclosed herein.

[0086] The multi-layer cooling busbars disclosed herein can increase the efficiency of electric powertrains in terms of one or more of cost, mass, or space by consolidating electrical and coolant paths into a single layered assembly.

[0087] Examples of multi-layered cooling busbars are described with reference to FIGS. 7-12. Illustratively, these multi-layered cooling busbars can be in a path between a first liquid-cooled component of an electrical system configured to store electrical energy and a second liquid-cooled component of the electrical system configured to use electrical energy. For example, the electrical system may be in an electric vehicle. Alternatively or additionally, these multi-layered cooling busbars can be in a path between a charging port of the electric vehicle and a battery of the electric vehicle. Any suitable principles and advantages of these multi-layered cooling busbars can be implemented with each other and / or with any other busbars disclosed herein. Any suitable principles and advantages of the electrical system disclosed herein can be applied to any other suitable electrical system. This disclosure describes the electrical system using the example of an electric vehicle for illustrative purposes.

[0088] FIG. 7 illustrates a cooling bus bar according to an embodiment. The cooling bus bar illustrated in FIG. 7 may implement one or more features described above, such as one or more features described above with reference to one or more of FIG. 1, FIG. 2A-FIG. 2F, and FIG. 6. Additionally, the cooling bus bar illustrated in FIG. 7 may be connected to the U-loop adapter 320 illustrated in FIG. 3A-FIG. 3C and / or the connection unit 400 illustrated in FIG. 4A-FIG. 4C. Such a connection may involve structural modifications of the U-loop adapter 320 and the connection unit 400. The cooling bus bar illustrated in FIG. 7 may be a single conductor cooling bus bar. The illustrated bus bar has two flat sides. As illustrated in FIG. 7, the cooling bus bar includes a conductor 702, a tube layer 704 having a conduit 705 for coolant to flow, an insulating layer 706, and a shielding layer 708. The insulating layer 706 and other insulating layers disclosed herein may be electrical insulating layers. Each of these insulating layers may be referred to as an insulating layer. Insulation layer 706 and / or other insulation layers disclosed herein can be implemented according to any suitable principles and advantages of insulation layers 224 and / or 222. Tube layer 704 includes an electrical insulation layer. Conductors 702 can carry high voltages for power distribution in electric vehicles. The number of conduits 705 included in the cooling busbar can be selected based on the particular application.

[0089] FIG. 8 illustrates a cooling busbar according to one embodiment. The cooling busbar is a single heat transfer busbar with an electrically conductive coolant tube layer. As shown in FIG. 8, the cooling busbar can include an electrically conductive coolant tube layer 802 having conduits 705 for coolant to flow through. The electrically conductive coolant tube layer 802 can be surrounded by an insulating layer 804 that electrically insulates the electrically conductive coolant tube layer 802 from the conductors 702. The insulating layer 804 can be surrounded by the conductors 702. The conductors 702 can be surrounded by an insulating layer 706. The insulating layer 706 can be further surrounded by a shielding layer 708.

[0090] FIG. 9 illustrates a cooling busbar according to an embodiment. The cooling busbar is a multi-layer cooling busbar and can include two or more conductive layers. As shown in FIG. 9, the cooling busbar can include a second conductor 902 in addition to the conductor 702. The cooling busbar shown in FIG. 9 can include the conductor 702, a tube layer 704 having a conduit 705 for coolant to flow through, and an insulating layer 706. The insulating layer 706 can be surrounded by the second conductor 902. The second conductor layer 902 can be surrounded by a second insulating layer 904. The second insulating layer 904 can be surrounded by a shielding layer 906. The conductors 702, 902 can provide separate power distribution paths for the cooling busbar of FIG. 9. Although two conductors 702 and 902 are shown in FIG. 9 for illustrative purposes, in certain applications, three or more conductors electrically isolated from one another can be implemented.

[0091] FIG. 10 is a diagram illustrating one embodiment of the cooling busbar of FIG. 9. Bidirectional coolant flow is illustrated in FIG. 10. As illustrated in FIG. 10, a cooling busbar having multiple fluid paths (e.g., conduits 705) may allow fluid to flow in different directions within the fluid paths. In certain applications, coolant may simultaneously flow in different directions within different respective fluid paths of the cooling busbar. For example, coolant may simultaneously flow in different (e.g., opposite) directions within different conduits 705 of the cooling busbar of FIG. 10.

[0092] FIG. 11 illustrates a cooling busbar according to one embodiment. The cooling busbar illustrated in FIG. 11 may implement one or more features described above, such as one or more features described with reference to one or more of FIGS. 1, 2A-2F, and 6-10. Additionally, the cooling busbar illustrated in FIG. 11 may be connected to a U-loop adapter 320 illustrated in FIGS. 3A-3C and / or a connection unit 400 illustrated in FIGS. 4A-4C. Such a connection may involve structural modifications of the U-loop adapter 320 and / or the connection unit 400. The cooling busbar of FIG. 11 has a circular cross-sectional shape, multiple conductors, and bidirectional coolant flow.

[0093] As shown in FIG. 11 , the central conduit 1102 may be surrounded by a first tube layer 1104. The first tube layer 1104 may be surrounded by a second conduit 1106. The number of conduits in the second conduit 1106 may be selected based on a particular application. One or more of the second conduits 1106 may have a different coolant flow direction than the central conduit 1102. The different coolant flow directions may be opposite coolant flow directions. In some cases, two of the second conduits 1106 may have different respective coolant flow directions. The second conduit 1106 may be surrounded by a second tube layer 1108. The second tube layer 1108 may be surrounded by a first conductor 1110. The first conductor 1110 may be surrounded by a first insulation layer 1112. The insulating layer 1112 may be surrounded by a second conductor layer 1114. The second conductor 1114 may be surrounded by a second insulating layer 1116. The second insulating layer 1116 may be surrounded by a shielding layer 1118. Any suitable number of conductors may be implemented for a particular application.

[0094] Figure 12 illustrates a cooling bus bar according to one embodiment. This cooling bus bar is similar to the cooling bus bar described in Figure 11, except that the cooling bus bar of Figure 12 has a single coolant path. As shown in Figure 12, a central conduit 1102 may be surrounded by a first tube layer 1104. The first tube layer 1104 may be surrounded by a first conductive layer 1110 without an intervening conduit.

[0095] In some embodiments, the busbar has one or more hollow portions and an inner rigid conductor. Such a busbar can include an insulating layer between the one or more hollow portions and the inner rigid conductor. Thus, the one or more hollow portions can be outside the insulating layer. A cooling medium can flow through the one or more hollow portions.

[0096] FIG. 13A is a cross-sectional view of a busbar according to one embodiment. The busbar is a circular busbar having an inner rigid conductor 1302 and an outer conductor 1308. Between the inner conductor 1302 and the outer conductor 1308 are respective insulating layers 1304. The outer conductor 1308 may surround the insulating layer 1304 and may include an extrusion having cooling channels, which may be a hollow portion 1306 configured for fluid (e.g., liquid coolant) to flow through. The hollow portion 1306 may be included around the outer diameter of the insulating layer 1304. Any suitable number of hollow portions may be implemented for a particular application. Cooling of the inner rigid conductor 1302 and the outer conductor 1308 may be provided by coolant flowing through the cooling channels of the hollow portion 1306 outside the insulating layer 1304. The flow direction of the coolant in each hollow portion 1306 may be the same direction or different directions.

[0097] FIG. 13B illustrates a busbar corresponding to FIG. 13A compared to a busbar having a solid outer conductor. The cooling busbar of FIG. 13A may be implemented using one or more suitable features of the cooling busbars described herein. For example, the cooling busbar of FIG. 13A may include one or more additional layers, such as one or more additional insulation layers, one or more conductors, one or more shielding layers, or colored layers. Additionally, the cooling busbar of FIG. 13A may be connected to the U-loop adapter 320 of FIGS. 3A-3C and / or the connection unit 400 of FIGS. 4A-4C. Such connection may involve structural modifications of the U-loop adapter 320 and / or the connection unit 400.

[0098] FIG. 14 illustrates a cooling busbar according to an embodiment. The cooling busbar illustrated in FIG. 14 may have similar features to the cooling busbar illustrated in FIG. 13A and FIG. 13B. The cooling busbar illustrated in FIG. 14 may be a flat laminated busbar having multiple inner rigid conductors 1402. The cooling busbar of FIG. 14 may include multiple inner rigid conductors 1402 within a single rigid shield layer. The inner rigid conductors 1402 may include both positive and negative conductors. Thus, a single cooling busbar may include positive and negative conductors, and each inner rigid conductor 1402 may be surrounded by an insulating layer 1404. The insulating layer 1404 may be surrounded by an outer conductor 1408. In some cases, the outer conductor 1408 may be a shielding layer. Alternatively or additionally, a shielding layer may be included around the outer conductor 1408. A hollow portion of the busbar is included outside the insulating layer 1404 of each of the inner rigid conductors 1402. Coolant can flow through the hollow portion to cool the inner rigid conductor 1402. The hollow portion 1406 can be located between the outer conductor 1408 and the insulating layer 1404. The hollow portion 1406 can provide bidirectional fluid flow in a particular application. Any suitable number of hollow portions can be implemented for a particular application. Coolant can flow through a conduit defined by the hollow portion 1406 to cool the inner rigid conductor 1402 and the output conductor 1408. The cooling bus bar of FIG. 14 can implement one or more suitable additional features of the cooling bus bars disclosed herein, such as one or more additional conductors, one or more additional insulating layers, one or more shielding layers, or color layers. Additionally, the cooling bus bar shown in FIG. 14 can be connected to the U-loop adapter 320 shown in FIGS. 3A-3C and / or the connection unit 400 shown in FIGS. 4A-4C. Such connection may involve structural modifications of the U-loop adapter 320 and / or the connection unit 400.

[0099] Unless the context clearly dictates otherwise, words such as "comprise," "comprising," "include," "including," and the like, throughout the specification and claims, should be construed in an inclusive sense, i.e., "including, but not limited to," as opposed to an exclusive or exhaustive sense. The term "coupled," as generally used herein, refers to two or more elements that may be directly connected or connected through one or more intermediate elements. Similarly, the term "connected," as generally used herein, refers to two or more elements that may be directly connected or connected through one or more intermediate elements. Where the context permits, words in the above detailed description using singular or plural numbers can also include plural or singular, respectively. The word "or" in connection with a list of two or more items encompasses all of the following interpretations of that word, namely, any of the items in the list, all of the items in the list, and any combination of the items in the list.

[0100] Additionally, conditional language used herein, particularly "can," "potential," "may," "such," "etc.," and the like, is generally intended to convey that certain embodiments include certain features, elements, and / or conditions, while other embodiments do not, unless specifically stated otherwise or understood otherwise within the context in which it is used. Thus, such conditional language is generally not intended to imply that features, elements, and / or conditions are in any way required for one or more embodiments.

[0101] The foregoing description has been described with reference to specific embodiments. However, the above illustrative description is not intended to be exhaustive or to limit the invention to the precise form described. Many modifications and variations are possible in light of the above teachings. This will enable those skilled in the art to best utilize the techniques and various embodiments with various modifications suitable for various applications.

[0102] Although the present disclosure and embodiments have been described with reference to the accompanying drawings, various changes and modifications will become apparent to those skilled in the art, and such changes and modifications should be understood to be included within the scope of the present disclosure.

Claims

1. A busbar comprising: a rigid conductor configured to carry current from a power source to a load; a hollow portion surrounded by the rigid conductor and configured to allow a cooling medium to flow therethrough; an inner tube layer disposed between the rigid conductor and the hollow portion; an insulating layer; and a shielding layer disposed such that the insulating layer is between the rigid conductor and the shielding layer. A power distribution system comprising:

2. The power distribution system of claim 1 , wherein the rigid conductor comprises at least one of aluminum or copper.

3. The power distribution system of claim 1, wherein the inner tube layer is configured to protect the rigid conductor from corrosion from the cooling medium.

4. The power distribution system of claim 3 , wherein the bus bar further comprises an electrical insulation layer, the electrical insulation layer disposed between an inner diameter of the rigid conductor and the inner tube layer.

5. A power distribution system as described in claim 1, further comprising a second hollow portion outside the outer diameter of the rigid conductor.

6. 2. The power distribution system of claim 1, wherein the rigid conductor has a first end and a second end, the first end and the second end each having an electrical contact area.

7. 10. The power distribution system of claim 1, wherein the insulating layer comprises at least one of cross-linked polyethylene (XLPE), polyvinyl chloride (PVC), nylon, silicone, a thermoplastic, or a thermoset plastic.

8. 10. The power distribution system of claim 1, wherein the bus bar is shaped for incorporation into an electric vehicle, the bus bar being shaped to fit into on-board packaging and extending from a charging port / inlet to a vehicle battery to the vehicle battery.

9. 10. The power distribution system of claim 1, further comprising a second bus bar comprising a second rigid conductor, a second hollow portion, a second insulating layer, and a second shielding layer.

10. 10. The power distribution system of claim 9, further comprising a coolant source, wherein the cooling medium flows from the coolant source to the bus bar and from the second bus bar to the coolant source.

11. 10. The power distribution system of claim 9, further comprising a U-loop adapter connected to the bus bar and the second bus bar, the second bus bar configured to provide a return flow of the cooling medium.

12. The power distribution system of claim 1 , further comprising a reservoir and a pump configured together to supply the cooling medium to the hollow portions of the bus bars.

13. The power distribution system of claim 1 , further comprising a charge port connection unit configured to connect the bus bar to the power source.

14. A battery, Charging port and a busbar including a rigid conductor configured to carry current in an electrical path from the charge port to the battery, a hollow portion surrounded by the rigid conductor and configured to allow a cooling medium to flow therethrough, an inner tube layer disposed between the rigid conductor and the hollow portion, an insulating layer, and a shielding layer disposed such that the insulating layer is between the rigid conductor and the shielding layer; An electric vehicle comprising:

15. a conductor configured to carry electrical energy between components of the electric powertrain; a conduit for a cooling medium, said conduit being surrounded by said conductor, said conductor and said conduit both being part of a single busbar assembly, said busbar being a rigid busbar; a tube layer surrounding the conduit, the tube layer being disposed between the conduit and the conductor; A bus bar comprising:

16. The busbar of claim 15 further comprising a second conduit.

17. 16. The busbar of claim 15, further comprising a second conductor and an insulating layer, the insulating layer disposed between the conductor and the second conductor.

18. The busbar of claim 15 , further comprising a shielding layer surrounding the conductor and an insulating layer disposed between the conductor and the shielding layer.

19. The busbar of claim 15 , wherein the tube layer comprises an electrical insulation layer configured to electrically insulate the conductors from a cooling medium flowing through the conduits.

20. 20. The busbar of claim 19, wherein the electrically insulating layer comprises at least one of polyethylene, nylon, polyvinyl chloride, a silicone thermoplastic, or a thermoset plastic.

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