Method for joining current collector patterned with multi-layer copper-graphene to battery can and motor stator winding

Abstract

An electrical connection for a vehicle and a method of forming an electrical connection for a vehicle. The electrical connection includes a first electrical component including a first bonding region. The electrical connector also includes a conductor including a second bonding region. The conductor is bonded to the first bonding region of the first electrical component at the second bonding region. In addition, the electrical connector includes a fusion zone formed in the first bonding region, the first electrical component. The conductor includes a copper-graphene multilayer composite material formed on a surface of the conductor, the composite material including at least one of the following composite structures: a) alternating layers of graphene and copper deposited on a substrate, b) graphene particles dispersed in a copper matrix, and c) alternating layers of graphene and copper deposited on a copper foil, wherein the copper foil is wrapped around the substrate.

Description

Background Art

[0001] Electric and hybrid - electric vehicle technologies have been enabled through the development and deployment of rechargeable auxiliary batteries, which supply energy to the electric traction motors, servo motors, and other electronic devices in the vehicle. A number of electrical connectors and electrical components are provided to transfer energy between the batteries, motors, and electrical components in the vehicle. For example, a traction motor includes a stationary stator and a rotor rotatably positioned within the stator. The stator may include a coil winding wound around teeth in the stator. When an alternating current (AC) is applied to the stator, the winding generates a magnetic field, and the permanent magnets in the rotor attempt to align with the magnetic field, causing the rotor to rotate within the stator. The winding is connected to a bus bar, which is then connected to additional components in the power distribution system.

[0002] However, in the power distribution of alternating current (AC), the current density tends to be greater near the surface of a conductor (such as the winding of the stator and the bus bar), while the current density near the core of the conductor decreases. This effectively reduces the cross - sectional area of a larger conductor and increases the effective resistance. This effect is called the skin effect and is enhanced as the frequency of the alternating current increases. To counteract this effect, several smaller conductors can be used instead of a larger conductor. Each smaller conductor has a smaller cross - sectional area than the larger conductor, but together they can exhibit a cross - sectional area similar to that of the larger conductor. In addition, coatings and other composite materials have been and are being developed to address and utilize the skin effect.

[0003] Although the existing conductors in the vehicle achieve their intended purpose, there is still a need for a new and improved conductor and a method of joining the conductor to other conductors and electrical components in a propulsion system and other applications. Summary of the Invention

[0004] According to several aspects, the present disclosure relates to an electrical connector for a vehicle. The electrical connector includes a first electrical component that includes a first engagement region. The electrical connector further includes a conductor that includes a second engagement region. The conductor is joined to the first engagement region of the first electrical component at the second engagement region. In addition, the electrical connector includes a fusion zone formed in the first engagement region of the first electrical component. The conductor includes a substrate that includes a first surface and a copper - graphene multi - layer composite material formed on the first surface. The copper - graphene multi - layer composite material includes at least one of the following composite structures: a) alternating layers of graphene and copper deposited on the substrate, b) graphene particles dispersed in a copper matrix, and c) alternating layers of graphene and copper deposited on a copper foil, where the copper foil wraps around the substrate.

[0005] In the above - mentioned embodiment, the substrate includes at least one material selected from the group consisting of copper, steel, and aluminum.

[0006] In any of the above embodiments, the electrical connector further includes a fusion zone formed in a first bonding region in a first electrical component.

[0007] In any of the above embodiments, graphene present in the fusion zone of the first electrical component is also included. In a further embodiment, a nickel layer is present between the first bonding region and the second bonding region, and nickel is present in the fusion zone of the first electrical component. Alternatively, the copper-graphene multi-layer composite material is not present on the first surface of the second bonding region.

[0008] In any of the above embodiments, the conductive adhesive contacts the first bonding region of the first electrical component and the second bonding region of the conductor. In a further embodiment, the conductive adhesive is at least one of a conductive paste and a conductive tape.

[0009] In any of the above embodiments, the first electrical component is a winding in a stator and the conductor is a bus bar. Alternatively, in any of the above embodiments, the first electrical component is a battery, and the battery includes a first bonding region formed by at least one of a tab and a terminal.

[0010] According to other aspects, the present disclosure relates to a method of forming an electrical connector for a vehicle. The method includes joining a first electrical component including a first bonding region to a conductor including a second bonding region. The conductor includes a substrate that includes a first surface and a copper-graphene multi-layer composite material formed on the first surface. The method further includes forming a fusion zone between the first bonding region in the first electrical component and the second bonding region in the conductor. The copper-graphene multi-layer composite material includes at least one of the following composite structures: a) alternating layers of graphene and copper deposited on the substrate, b) graphene particles dispersed in a copper matrix, and c) alternating layers of graphene and copper deposited on a copper foil, where the copper foil wraps around the substrate.

[0011] In the above embodiments, the joining includes laser welding. Alternatively, the joining is performed by at least one of the following welding processes: ultrasonic welding and friction welding.

[0012] In any of the above embodiments, graphene is present in the first electrical component in the fusion zone. In a further embodiment, the method further includes providing nickel in the form of a foil between the first bonding region and the second bonding region before joining, and nickel is present in the first electrical component in the fusion zone. In an alternative or additional embodiment, the method further includes supplying nickel in the form of a wire, and the nickel is supplied between the first bonding region and the second bonding region. Nickel is present in the first electrical component in the fusion zone. Alternatively, the method further includes removing a portion of the copper-graphene multi-layer composite material from the first surface at the second bonding region before joining the first electrical component to the conductor, where the laser power during the removal is less than the laser power during the joining.

[0013] In any of the above embodiments, the first electrical component includes a secondary battery, where the secondary battery is a pouch cell including tabs, and the first bonding region is located on the tabs. Alternatively or additionally, in any of the above embodiments, the first electrical component includes a secondary battery, where the secondary battery is a cylindrical cell including terminals, and the first bonding region is positioned at the terminals.

[0014] In any of the above embodiments, the method includes bonding a first electrical component including a steel terminal and a first bonding region on the steel terminal to a second bonding region of a conductor. The first electrical component is a secondary battery, and the conductor is formed of copper. The method further includes forming a first fusion zone in the first bonding region and the first electrical component, bonding a second electrical component including a fourth bonding region to a third bonding region of the conductor, and forming a second fusion zone in the fourth bonding region and the second electrical component. Alternatively, in any of the above embodiments, the method includes bonding a first electrical component to a conductor formed of copper. The first electrical component is a winding that provides the first bonding region, and the conductor is a busbar that provides the second bonding region.

[0015] According to yet another aspect, the present disclosure relates to a method for bonding electrical components for a vehicle. The method includes applying an adhesive layer to a first bonding region of a first electrical component and applying the adhesive layer to a second bonding region of a conductor, where the conductor includes a substrate having a first surface and a copper-graphene multi-layer composite material located on the first surface. The method further includes bonding the first electrical component to the conductor, where the adhesive layer includes at least one of a conductive adhesive and a conductive tape. The copper-graphene multi-layer composite material includes at least one of the following composite structures: a) alternating layers of graphene and copper deposited on the substrate, b) graphene particles dispersed in a copper matrix, and c) alternating layers of graphene and copper deposited on a copper foil, where the copper foil wraps around the substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings described herein are for illustrative purposes only and are not intended to limit the scope of the present disclosure in any way.

[0017] Figure 1 Vehicles including a propulsion system utilizing an electric traction motor according to various embodiments of the present disclosure are shown;

[0018] Figure 2A The traction motor stator according to various embodiments of the present disclosure is shown;

[0019] Figure 2B The windings in a motor coupled to a busbar according to various embodiments of the present disclosure are shown;

[0020] Figure 3AShows a top view of a plurality of battery cells in a battery pack according to various embodiments of the present disclosure, wherein each battery cell includes a current collector;

[0021] Figure 3B Shows a plurality of current collectors coupled to a cylindrical secondary battery;

[0022] Figure 4A Shows a battery pouch including a conductor tab according to various embodiments of the present disclosure;

[0023] Figure 4B Shows a battery pouch including a conductor tab according to various embodiments of the present disclosure;

[0024] Figure 5A Shows a cross-sectional view along the axis of a conductor according to various embodiments of the present disclosure;

[0025] Figure 5B Shows according to various embodiments of the present disclosure perpendicular to Figure 5A Cross-sectional view of the axis of the conductor;

[0026] Figure 6 Shows a copper conductor including a composite copper-graphene multi-layer composite coating welded to a first electrical component according to various embodiments of the present disclosure;

[0027] Figure 7A Shows a copper conductor including a composite copper-graphene coating according to various embodiments of the present disclosure, the copper conductor being arranged adjacent to a conductor including a nickel foil positioned between the composite copper-graphene coating and a target;

[0028] Figure 7B Shows a copper conductor including a composite copper-graphene multi-layer composite coating welded to a target according to various embodiments of the present disclosure;

[0029] Figure 8A Shows a copper conductor including a composite copper-graphene multi-layer composite coating welded to a target according to various embodiments of the present disclosure, wherein a part of the coating is removed before welding;

[0030] Figure 8B Shows according to various embodiments of the present disclosure including welding to Figure 8A Copper conductor of the composite copper-graphene multi-layer composite coating of the target;

[0031] Figure 9 Shows a copper conductor including a composite copper-graphene multi-layer composite coating adhered to a target according to various embodiments of the present disclosure;

[0032] Figure 10shows direct welding of two copper conductors including a composite copper-graphene multilayer composite coating welded together according to various embodiments of the present disclosure;

[0033] Figure 11 A schematic diagram of a welding process according to various embodiments of the present disclosure is shown. DETAILED DESCRIPTION

[0034] The following description is merely exemplary in nature and is not intended to limit the present disclosure, application or use. Furthermore, it is not intended to be bound by any express or implied theory presented in the foregoing background technology, summary of the invention or the following detailed description. It should be understood that throughout the drawings, corresponding reference numerals indicate similar or corresponding parts and features.

[0035] Reference will now be made in detail to several examples of the present disclosure illustrated in the accompanying drawings. Whenever possible, the same or similar reference numerals are used in the drawings and the description to represent the same or similar parts or steps. The drawings are in simplified form and are not drawn to exact scale.

[0036] The present disclosure relates to electrical connections and methods of forming electrical connections and circuits in a vehicle's energy storage and propulsion system, including battery modules and electric machines.

[0037] As used herein, the term "vehicle" is not limited to automobiles. Although the present technology is described primarily in conjunction with electric vehicles herein, the present technology is not limited to electric vehicles, but also includes hybrid electric vehicles and internal combustion engines. In addition, these concepts can also be used in a variety of applications, such as related components used in motorcycles, mopeds, locomotives, aircraft, ships and other vehicles, and related components used in other applications using electrical connectors, such as related components used in portable power stations, for example, portable power stations for powering remote work locations and emergency backup power, and permanent power stations associated with buildings and equipment, all of which can be powered by, for example, solar or wind turbine generator systems, power sources and fuel generators, such as gasoline generators or diesel generators and Stirling engines.

[0038] Figure 1 The vehicle 100 is shown including an energy storage and propulsion system 120. The energy storage and propulsion system 120 includes a plurality of electrical components (i.e., components that generate, transmit, or change power) forming an electrical circuit for propelling the vehicle 100, such as batteries, electric motors, power electronics modules and devices within the power electronics modules, and electrical conductors connecting the electrical components together or present within the electrical components, etc., as further described herein.

[0039] As described above, the energy storage and propulsion system 120 generally includes an electric motor 124 and an auxiliary battery 126 for powering the electric motor 124. Additionally, in many embodiments, the propulsion system 120 includes an inverter 128 for converting electrical power from DC (direct current) provided by the battery 126 to AC (alternating current) used by the electric motor 124. The inverter 128 may be included within a power electronics module 130 that includes, for example, transistors and diodes for switching electrical power from DC to AC and vice versa. In an embodiment, the battery 126 is connected to the electric motor 124 through the power electronics module 130.

[0040] A controller 132 may also be included within the power electronics module 130 or otherwise connected to the power electronics module 130. The controller 132 is connected to the inverter 128 and is programmed to control and manage the operation of the electric motor 124 and associated hardware, including the inverter 128. The electric motor 124 is connected to a transmission (drive unit) 136 and a driveline 138 that transfers mechanical power and rotation to the wheels 140 of the vehicle 100. The controller 132 includes one or more processors and a tangible non-transitory memory 134.

[0041] Referring again to the electric motor 124, the electric motor 124 powered by the battery 126 includes a stator 142 and a rotor 144 rotatably disposed within the stator 142. The stator 142 is the stationary part of the electric motor 124. When energized with alternating current (AC), the stator 142 provides a rotating magnetic field, and the stationary magnetic field of the rotor 144 attempts to align with the rotating magnetic field, causing the rotor 144 to rotate, which can be referred to as the "electric" mode. In a traction electric vehicle application, the electric mode provides propulsion force to the vehicle 100. In other applications, the rotating field of the rotor 144 (caused by physical rotation) generates current in the stator 142 - this mode of operation is called "generation", and the electric motor 124 used in this way is used as a generator. The generation mode captures some of the energy recovered from braking, for example, when the vehicle is decelerating and stopping, and stores this energy back into the battery 126.

[0042] Reference Figure 2A and 2B shows an embodiment of the electrical components and specifically shows the stator 142. The stator 142 generally may include a plurality of coil windings 148 formed by one or more conductors, as further described herein. The coil windings 148 are also connected to one or more busbars 150 that connect the coil windings 148 directly or indirectly through additional conductors 122 to the inverter 128 and the battery 126 within the power electronics module 130, as Figure 1 shown.

[0043] Figure 3A and 3BAnother embodiment of an electrical component is shown, particularly a secondary battery 154 arranged in an array 152. As shown, the secondary battery 154 is a cylindrical battery. A secondary battery is understood herein as a rechargeable battery. That is, a secondary battery can store charge, release charge, and can be recharged to store charge again. The secondary battery 154 can include, for example, a lithium-ion battery and a nickel-metal hydride battery. The secondary battery 154 shown is a cylindrical battery and includes a cell can 156 that houses an anode, an anode current collector, a cathode, a cathode current collector, a separator, and an electrolyte that are wound inside the cell can 156. The cell can 156 includes a positive terminal 158 connected to the cathode current collector and a negative terminal 160 connected to the anode current collector. In an embodiment, the cell can 156 includes steel or aluminum, and the positive terminal 158 and the negative terminal 160 include one or more of steel, aluminum, and copper. Conductors 164 are used to connect the cell cans 154 in the array 152 together and to other components in the energy storage and propulsion system 120.

[0044] Figure 4A and 4B Another embodiment of an electrical component is shown, and another embodiment of a secondary battery 170 is specifically shown. As shown, the secondary battery 170 is a pouch battery. The pouch secondary battery 170 can also include, for example, a lithium-ion battery and a nickel-metal hydride battery. The pouch battery 170 includes a pouch 172 that houses an anode, an anode current collector, a cathode, a cathode current collector, a separator, and an electrolyte. Extending from the same end or from either end of the pouch 172 are tabs 174, 176 that are coupled to the cathode current collector and the anode current collector located in the battery 170. The tabs 174, 176 are formed of one or more of steel, aluminum, and copper. Conductors (not shown) are used to connect multiple pouches together, for example, in the Figure 3A battery array shown, and to additional electrical components in the energy storage and propulsion system 120.

[0045] In an embodiment, the conductors 122, 148, 164 (collectively referred to as conductors 180) are formed of a composite material, an embodiment of which is in Figure 5A and 5Bis shown. Conductor 180 includes a substrate 182, e.g., a wire, foil, or trace deposited on a carrier. In an embodiment, the material of substrate 182 is copper. Alternatively, the material of substrate 182 can be any material formed of a conductive material that exhibits a conductivity of at least 1x10^7 siemens per meter (S / m) at 20 degrees Celsius, e.g., in the range of 1x10^7 S / m at 20 degrees Celsius to 6.3x10^7 S / m at 20 degrees Celsius. Thus, in alternative embodiments, the conductor includes at least one or more of the following: steel, aluminum, aluminum alloy, and copper alloy. Substrate 182 can exhibit a thickness or diameter in the range of 0.01 mm to 10 mm, including all values and ranges therebetween, such as 0.5 mm to 5 mm. Additionally, substrate 182 can exhibit any number of cross-sections, including square (as Figure 5B shown), hexagonal, rectangular, oval, elliptical, pentagonal, etc.

[0046] The substrate includes a surface 184, including a copper-graphene multilayer composite 186 formed on surface 184. In an embodiment, the copper-graphene multilayer composite 186 exhibits a conductivity in the range of 105% to 400% of the International Annealed Copper Standard (IACS), including all values and ranges therebetween. The International Annealed Copper Standard (IACS) is understood as the percentage of the conductivity of a material relative to copper, with copper considered 100% conductive and referring to copper having a resistivity of 1.7241 microohm-cm at 20 degrees Celsius. The copper-graphene multilayer composite exhibits a variety of composite structures. In an embodiment, the copper-graphene multilayer composite 186 includes one or more alternating layers of copper and graphene deposited on substrate 182. In such embodiments, graphene is first deposited on each substrate 182, then copper is deposited on the graphene, and the process is repeated until there is a desired number of layers. In additional or alternative embodiments, graphene particles are dispersed between multiple coated copper layers. In yet another embodiment as described above, copper and graphene can be deposited on a copper foil in a manner of alternating layers of copper and graphene or together with graphene particles in a copper matrix, and then the copper foil can be wrapped around substrate 182. The copper-graphene multilayer composite of any of the above embodiments can be directly coated onto substrate 182 or wrapped around a copper foil on substrate 182 using one of several techniques, such as electrochemical deposition, electrodeposition, physical vapor deposition, chemical vapor deposition, and layer-by-layer assembly. The copper-graphene multilayer composite 186 can exhibit a thickness in the range of 5 nm to 500 microns, including all values and ranges therebetween, such as in the range of 30 microns to 300 microns. When there is a foil, in addition to the remaining copper-graphene multilayer composite, the foil exhibits a thickness in the range of 5 microns to 25 microns, including all values and ranges therebetween.

[0047] The conductor 180 is joined to one or more electrical components, such as other conductors as further described herein, Figure 6 the battery 126, the individual battery cells 154, 170 connected together, the electric machine 124, including the individual windings 148 in the stator 142 and the busbars 150 coupled to the windings 148, the inverter 128, the power electronics module 130, including components therein, such as the controller 132 and the non-transitory memory 134, and other electronic components present in the energy storage and propulsion system 120 of the vehicle 100. The conductor 180 and the electrical components are joined at the joint regions present on the conductor 180 and the electrical components.

[0048] For example, referring to Figure 6 , an embodiment of the conductor 180 joined to the first electrical component 190 is shown. The conductor 180 includes a joint region 192 and the electrical component 190 includes a joint region 194. Thus, as understood herein, the joint region is a region on the surface of the conductor 180 or the electrical component 190 where the conductor 180 and the electrical component 190 are joined together. For example, the joint region 194 may be present on the busbar 150 of the stator 142, on the positive electrode 158 or the negative electrode 160 of the cylindrical battery 154, or on the tabs 174, 176 of the pouch battery. A fusion zone 196 is formed in the joint regions 192, 194. In an embodiment, as Figure 6 shown, the fusion zone 196 extends into the surface of the electrical component 190 and in an embodiment extends beneath the surface of the electrical component 190 and through the conductor 180. When using a welding process as further described herein, one or more fusion zones 196 may include materials present in the joint region 192 of the conductor 180 and the joint region 194 of the electrical component 190, such as the material forming the substrate 182 of the conductor, the copper-graphene multi-layer composite material 186 formed on the surface of the conductor 180, and the material from the first electrical component 190. These materials may be mixed into the surface of one or both of the joint regions 192, 194 in the fusion zone 196 and, in an embodiment, beneath its surface. Alternatively, the fusion zone 196 may extend only into the surface of the electrical component 190 or only into the surface of the conductor 180; or the fusion zone 196 may remain at the surface of the electrical component 190 and the conductor 180, as shown in FIG. 8 further discussed herein.

[0049] In an embodiment, the conductor 180 and the electrical component 190 are joined by a welding process, such as a laser welding process, a friction welding process, or an ultrasonic welding process. The laser welding process includes a process of melting and joining the joining area using a laser beam. The friction welding process utilizes the generation of friction to melt and join the joining area together, and includes processes such as friction stir welding, rotational friction welding, and linear friction welding. The ultrasonic welding process employs a process of using local high-frequency ultrasonic vibrations.

[0050] Figure 6 An example of the welding process is shown, where the first electrical component 190 includes a first joining area 192 joined to a second joining area 194 of the conductor 180. The conductor 180 is welded to the first electrical component 190 using a laser. The laser beam 198 is incident on a surface 200 opposite to the second joining area 194, and the laser beam energy passes through the conductor 180 into the electrical component 190, thereby forming a fusion zone 196 in the conductor 180 and the electrical component 190. In an embodiment, a portion of the conductor 180 (including copper and graphene from the copper-graphene multi-layer composite) is dispersed into the fusion zone 196 in the electrical component 190, as described above.

[0051] However, in an embodiment, graphene may be harmful to the joint formed between the conductor 180 and the electrical component 190. Therefore, without being bound by any particular theory, the wettability of graphene can be adjusted by adding nickel to the welded joint. As Figure 7A and 7B shown, a nickel foil 202 is inserted between the first joining area 192 and the second joining area 194. Then the conductor 180 is welded to the first electrical component 190 using a laser. The laser beam 198 is incident on a surface 200 opposite to the second joining area 194, and then the laser beam energy passes through the conductor 180 into the electrical component 190, thereby forming a fusion zone 196 in the conductor 180 and the electrical component 190. In an embodiment, a portion of the conductor (including copper and graphene from the copper-graphene multi-layer composite) 180 and the nickel foil 202 are dispersed into the fusion zone 196 in the electrical component 190. As an alternative to the nickel foil 202, a nickel wire can be supplied between the first joining area 192 and the second joining area 194, especially in embodiments where the first joining area 192 and the second joining area 194 exhibit a relatively large joining area geometry.

[0052] Alternatively or additionally, relative to Figure 7A and 7B the embodiment shown in Figure 8A and 8BA method is shown in which a portion of the copper-graphene multi-layer composite material 186 located on the first surface opposite the second bonding region 194 is removed before bonding. Using a short-pulse laser or a defocused laser beam, which exhibits a lower power at the incident surface 200 than the power used to weld the conductor 180 and the electrical component 190 together, the copper-graphene multi-layer composite material 186 is ablated starting from the surface 200 relative to the second bonding region 194. Once the copper-graphene multi-layer composite material 186 is ablated from the opposite surface 200 to the second bonding region 194, the laser beam 198 is applied at a higher power and incident on the conductor surface 184. The laser beam energy passes through the conductor 180 into the electrical component 190, forming a fusion zone 196 in the conductor 180 and the electrical component 190. In an embodiment, a portion of the conductor 180 (including copper and graphene from the copper-graphene multi-layer composite material in the second bonding region 194) is dispersed into the fusion zone 196 in the electrical component 190. In other embodiments, the copper-graphene multi-layer composite material 186 is also removed from the second bonding region 194.

[0053] Although the above process is shown as using a laser for processing, it should be understood that other processes as described above can be used to bond the conductor 180 to the electrical component 190. Additionally, the ablation of the copper-graphene multi-layer composite material can be performed using alternative processes such as an etching process or a sanding process.

[0054] Figure 9 Another embodiment is shown in which the electrical component 190 is bonded to the conductor 180 using a conductive adhesive 210, and the conductive adhesive 210 is applied to the bonding region 192 of the conductor 180 and the bonding region 194 of the electrical component 190. In an embodiment, the conductive adhesive 210 exhibits a conductivity of at least 1 x 10^6 siemens per meter (S / m) at 20 degrees Celsius. For example, the conductivity ranges from 1 x 10^7 S / m at 20 degrees Celsius to 6.3 x 10^7 S / m at 20 degrees Celsius. The conductive adhesive includes at least one of a conductive glue or a conductive tape (such as a double-sided conductive tape). The conductive adhesive 210 conducts current through the thickness of the conductive adhesive 210. The conductive adhesive 210 forms a fusion zone 196 at the first bonding surface 192 and the second bonding surface 194.

[0055] Figure 10Another embodiment is shown in which two conductors 180, 190 are directly welded together. End portions of each of the conductors 180, 190 form a first joint area 192 and a second joint area 194, respectively. When the two conductors 180, 190 are welded together, a fusion zone 196 is formed between the conductors 180, 190. As shown, the copper-graphene multi-layer composite material 186 is removed from the first joint area 192 and the second joint area 194. In an alternative embodiment, the copper-graphene multi-layer composite material 186 remains on the surface 184 of the conductors 180, 190, and a nickel foil or nickel wire is positioned between the first joint area 192 and the second joint area 194.

[0056] Figure 11 An overall method of forming an electrical connection in an electric machine or forming a circuit in an electric machine is shown. Method 1100 includes joining a conductor 180 to a joint area of a first electrical component 190 at joint area 194 at block 1110. At block 1120, optionally, at least a portion of the copper-graphene multi-layer composite material 186 is removed from at least one surface 184 of the conductor 180, typically on the surface opposite the joint area 194 of the conductor 180. At block 1130, a fusion zone is formed at the joint area 192 of the electrical component 190 and the conductor 180. At block 1140, if the conductor 180 is to be joined to a second component, such as an additional battery cell 154, 170, or an additional conductor 190, then the process is repeated and the conductor 180 is joined to the joint area of the second component at an additional joint area. At block 1150, optionally, the copper-graphene multi-layer composite material 186 is removed from at least one surface of the conductor 180, typically on the surface opposite the additional joint area of the conductor 180. At block 1160, a fusion zone 196 is then formed between the conductor 180 and the second electrical component 190.

[0057] The connection between a conductor including a copper-graphene multi-layer composite coating and a target conductor provides many advantages. These advantages include the ability to provide a conductor including a composite coating for utilizing the skin effect. Another advantage of the welding is to provide a method of connecting a copper-graphene multi-layer coating to a target material (such as a battery steel can). Although the ordered structure of the graphene layer may be disrupted in the fusion zone, the conductivity of the composite material remains relatively high. In addition, the use of nickel provides an additional advantage of increasing the wettability of graphene in the fusion zone. If the ordered structure of graphene in the copper-graphene multi-layer composite material is maintained, additional methods of connecting the coated conductor and the target material can be used. In addition, defocused beam ablation and welding can also advantageously reduce graphene defects.

[0058] As used herein, the terms "controller" and related terms such as microcontroller, control module, module, control, control unit, processor, and like terms refer to one or more combinations of application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), electronic circuits, central processing units (such as microprocessors and related non-transitory memory components in the form of memory and storage devices (read only, programmable read only, random access, hard disk, etc.)). Controller 132 can also be composed of multiple controllers that are electrically connected to each other. Controller 132 can be interconnected with additional systems and / or controllers of vehicle 100, allowing controller 132 to access data such as the speed, acceleration, braking, and steering angle of vehicle 100.

[0059] The processor can be a custom or off-the-shelf processor, a central processing unit (CPU), a graphics processing unit (GPU), an auxiliary processor among several processors associated with the controller, a semiconductor-based microprocessor (in the form of a microchip or chipset), a macroprocessor, a combination thereof, or generally a device for executing instructions.

[0060] The tangible non-transitory memory 134 can include, for example, volatile and non-volatile storage devices such as read only memory (ROM), random access memory (RAM), and keep alive memory (KAM). KAM is a persistent or non-volatile memory that can be used to store various operating variables when the processor is powered off. The tangible non-transitory memory 134 can be implemented using multiple storage devices, such as PROM (programmable read only memory), ePROM (electrically PROM), EEPROM (electrically erasable PROM), flash memory, or other electrical, magnetic, optical, or combined storage devices capable of storing data, some of which represents executable instructions used by controller 132 to control the various systems of vehicle 100.

[0061] The description of the present disclosure is merely exemplary in nature, and variations that do not depart from the gist of the present disclosure are intended to fall within the scope of the present disclosure, and these variations should not be regarded as departing from the spirit and scope of the present disclosure.

Claims

1. An electrical connector for a vehicle, comprising: a first electrical component, the first electrical component comprising a first bonding area; as well as A conductor comprising a second bonding region, wherein the conductor is bonded to the first bonding region of the first electrical component at the second bonding region, wherein the conductor comprises a substrate having a first surface, and a copper-graphene multilayer composite material formed on the first surface, wherein the copper-graphene multilayer composite material comprises at least one of the following composite structures: a) alternating layers of graphene and copper deposited on the substrate, b) graphene particles dispersed in a copper matrix, and c) alternating layers of graphene and copper deposited on a copper foil, wherein the copper foil is wrapped around the substrate. 2 . The electrical connector of claim 1 , wherein the substrate comprises at least one material selected from the group consisting of copper, steel, and aluminum. 3 . The electrical connector of claim 2 , further comprising a fusion zone formed in the first joining region of the first electrical component.

4. The electrical connector of claim 3, further comprising graphene present in the fusion zone of the first electrical component.

5. The electrical connector of claim 4, further comprising a nickel layer present between the first joining region and the second joining region and nickel present in the fusion zone of the first electrical component. 6 . The electrical connector of claim 3 , wherein the copper-graphene multi-layer composite material is not present on the first surface of the second bonding region.

7. The electrical connector of claim 1 further comprising a conductive adhesive contacting the first bonding area of ​​the first electrical component and the second bonding area of ​​the conductor, and wherein the conductive adhesive is at least one of a conductive glue and a conductive tape.

8. The electrical connector of claim 1, wherein the first electrical component is a winding in a stator and the conductor is a busbar.

9. The electrical connector of claim 1, wherein the first electrical component is a battery and the battery includes the first engagement region, the first engagement region being provided by at least one of a tab and a terminal.

10. A method of forming an electrical connector for a vehicle, comprising: bonding a first electrical component including a first bonding region to a conductor including a second bonding region, wherein the conductor includes a substrate having a first surface and a copper-graphene multilayer composite material formed on the first surface; as well as forming a fusion zone between the first joining region in the first electrical component and the second joining region in the conductor, The copper-graphene multilayer composite material comprises at least one of the following composite structures: a) alternating layers of graphene and copper deposited on the substrate, b) graphene particles dispersed in a copper matrix, and c) alternating layers of graphene and copper deposited on a copper foil, wherein the copper foil is wrapped around the substrate.

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