Method for energy transmission between two electric vehicles with an external control unit, such a control unit and a system with a control unit and a charging cable

Abstract

Method for controlling energy transmission via a charging cable (100) between two electric vehicles (300, 400) using an external control unit (200), wherein the control unit (200) comprises a first processor (234), a first memory (230) with first program instructions (236) and one or more first communication interfaces (208, 211, 212), wherein the charging cable (100) comprises a control unit (105) with a second processor (122) and a second memory (120) with second program instructions (124), wherein the charging cable (100) further comprises at least one second communication interface (104), wherein execution of the second program instructions (124) by the second processor (122) controls the charging cable (100) at least to communicate via the second communication interface (104), wherein the control unit (200) is configured to execute a method for controlling the energy transfer between the two electric vehicles (300, 400) via the charging cable (100) upon execution of the first program instructions (236) by the first processor (234), the method comprising: Establishing a first communication connection between the control unit (200) and the control unit (105) of the charging cable (100), Receiving one or more charging parameters of both electric vehicles (300, 400) by the control unit (200), wherein first charging parameters of the received charging parameters identify a first of the two electric vehicles (300) as an electric vehicle to be received by energy and indicate a first maximum current when receiving energy, wherein second charging parameters of the received charging parameters identify the second of the two electric vehicles (400) as an electric vehicle delivering energy and indicate a second maximum current when delivering energy, wherein the control unit (200) further establishes a second wireless communication connection to the first electric vehicle (300), wherein the control unit (200) receives the first charging parameters from the first electric vehicle (300) via the second communication connection, wherein the control unit (200) further establishes a third wireless communication connection to the second electric vehicle (400), wherein the control unit (200) receives the second charging parameters from the second electric vehicle (400) via the third communication connection, Determining a transmission current for the energy transfer from the second to the first electric vehicle (300, 400) using the first and second maximum currents by the control unit (200), which is forwarded to the participating electric vehicles so that their charging controllers carry out the energy transfer accordingly, Sending one or more control commands from the control unit (200) to the control unit (105) of the charging cable (100), wherein the control commands are configured, upon execution by the second processor, to control the energy transfer between the two electric vehicles (300, 400), wherein the control commands comprise an indication of the transmission current intensity to be used for the energy transfer from the second to the first electric vehicle (300, 400) via the charging cable (100).

Description

[0001] The invention relates to a method for controlling energy transmission via a charging cable between two electric vehicles using an external control unit, a corresponding control unit and a system comprising a corresponding control unit and a corresponding charging cable.

[0002] Electromobility, i.e., the use of electrically powered vehicles for the transport of people and goods, is widely viewed as a key building block for a future sustainable and climate-friendly transport system based on renewable energies. Electromobility therefore plays a key role in the desired transport transition toward transport and mobility based on sustainable energy sources, gentle mobility use, and the networking of various forms of individual transport and local public transport. Electromobility refers to the mobility of people and goods within geographical space using electric drives. In this context, one of the key advantages of electric vehicles over conventional combustion-engine vehicles is their zero local exhaust emissions.

[0003] One of the problems facing electric vehicles, particularly during the development of charging infrastructure, is the limited availability of charging stations. Electric vehicles can be charged using alternating current (AC) and / or direct current (DC). While electric vehicles capable of AC charging can, in principle, be charged at any power outlet with an appropriate adapter cable, such outlets are not available everywhere. On the other hand, the network of publicly accessible charging stations for electric vehicles has not yet been comprehensively developed. Combined with the long charging times of the batteries used, this means that longer journeys in particular require careful route and time planning.

[0004] If an electric vehicle no longer has sufficient energy to move and there is no charging station available, the problem arises as to how it can be recharged. Such a situation can arise, for example, if an electric vehicle breaks down due to a lack of energy and there is no charging station nearby. This problem is exacerbated by the limited availability of charging stations. However, it also arises in general if an electric vehicle breaks down inside or outside of a built-up area. Especially outside of built-up areas, the probability of a charging station being nearby is low.

[0005] An alternative way to charge an electric vehicle at a charging station is to transfer energy from one electric vehicle to another. JP 2010-252520 A describes a method for transferring energy between two electric vehicles using a charging cable that connects the two electric vehicles.

[0006] FR 2 978 303 A1 describes a method that involves connecting a charging circuit of a vehicle battery to be charged to a charging circuit of a bidirectional battery power supply. The charging circuit is used to perform controlled charging of the battery to be charged. A controlled power supply is passed to the charging circuit of the power supply. The charging circuit of the power supply is equipped with a bidirectional charger that converts AC voltage to DC voltage.

[0007] The article by Enim Ucer et al., "A Flexible V2V Charger as a New Layer of Vehicle-Grid Integration Framework," 2019 IEEE Transportation Electrification Conference and Expo, pages 1 to 7, describes a method for sharing electric vehicle-to-electric vehicle (V2V) charge. Power transfer between the electric vehicles is achieved via a conductive bidirectional DC-DC converter, which can take place in workplace parking lots, campuses, residential buildings, and highways.

[0008] WO 2018 / 101702 A1 describes a charging system for an electric vehicle. The charging system includes: a battery for performing both charging and discharging, a boost unit for boosting the battery's output voltage to a preset voltage, a charging port for receiving power from outside the charging system or providing power to the outside, a switch for directly connecting the battery and the charging port or for connecting the boost unit and the charging port according to a charging or discharging mode of the charging system, and a control unit for controlling the switch according to the charging or discharging mode of the charging system. When the charging system is in charging mode, the control unit controls the switch so that the charging port and the battery are directly connected. In this case, the battery is charged by the externally supplied power.When the charging system is in discharge mode, the switch is controlled so that a battery output is connected to the charging port via the boost unit. In this case, battery power is supplied to the outside.

[0009] DE 10 2020 104 357 A1 describes methods, devices, storage media, and systems for a device located at an edge of a vehicle communication network, or vehicles within a coverage area of ​​the device. The device generates a list of vehicle safety data to be distributed to vehicles currently located within a coverage area of ​​the device, based at least in part on a context related to the vehicles. The device further announces on a control channel communicatively coupling the device and the vehicles that the list of vehicle safety data is available and announces a service channel for receiving the list of vehicle safety data. The list of vehicle safety data is provided to the vehicles via the service channel.

[0010] DE 10 2018 205 614 A1 describes a method for providing a charging option by a parked motor vehicle, wherein the motor vehicle has an energy storage device for storing electrical energy and can be put into an energy output state in which, when a charging object is connected to the motor vehicle, energy stored in the energy storage device can be transferred to the charging object, wherein before or upon entering the energy output state, energy output information comprising the position of the motor vehicle is provided, which energy output information can be retrieved or received by a possible charging object and / or by a retrieval device belonging to a person assigned to the charging object.

[0011] WO 2018 / 056 272 A1 describes a device comprising a power supply side identification information acquisition unit that acquires power supply side identification information for identifying the power supply side from a device or a communication terminal of a user on the power supply side; a power receiving side identification information acquisition unit that acquires power receiving side identification information for identifying the power receiving side from a device or a communication terminal of a user on the power receiving side; a power supply information acquisition unit that acquires power supply information about an amount of power supplied by the device on the power supply side or an amount of power supplied to the device on the power receiving side;and a transmission unit that links the power supply side identification information, the power reception side identification information, and the power supply information and transmits them to a transaction management device;

[0012] The invention is therefore based on the object of creating an improved method for energy transmission between two electric vehicles.

[0013] The problem underlying the invention is solved by the features of the independent patent claims. Embodiments of the invention are specified in the dependent patent claims.

[0014] Execution methods include a method for controlling energy transfer via a charging cable between two electric vehicles using an external control unit. The control unit includes a first processor, a first memory with first program instructions, and one or more first communication interfaces. The charging cable includes a control unit with a second processor and a second memory with second program instructions. Furthermore, the charging cable includes at least one second communication interface. Execution of the second program instructions by the second processor controls the charging cable at least to communicate via the second communication interface. The control unit is configured, upon execution of the first program instructions by the first processor, to execute a method for controlling energy transfer between the two electric vehicles via the charging cable.

[0015] The procedure includes: Establishment of a first communication connection between the control unit and the control unit of the charging cable, Receiving one or more charging parameters of both electric vehicles by the control unit, wherein first charging parameters of the received charging parameters identify a first of the two electric vehicles as an electric vehicle to be received by energy and specify a first maximum current when receiving energy, wherein second charging parameters of the received charging parameters identify the second of the two electric vehicles as an electric vehicle delivering energy and specify a second maximum current when delivering energy, Determining a transmission current for the energy transfer from the second to the first electric vehicle using the first and second maximum currents by the control unit, Sending one or more control commands from the control unit to the control unit of the charging cable, wherein the control commands are configured, upon execution by the second processor, to control the energy transfer between the two electric vehicles, wherein the control commands include an indication of the transfer current to be used for the energy transfer from the second to the first electric vehicle via the charging cable.

[0016] Embodiments may have the advantage of enabling energy transfer between two electric vehicles, i.e., vehicle-to-vehicle energy transfer or electric vehicle to electric vehicle charging (EVEVC). Such vehicle-to-vehicle energy transfer can be used, for example, if an electric vehicle requires energy and there is no charging station nearby. For example, the corresponding electric vehicle has broken down due to a lack of energy.

[0017] The external control unit is a control unit that is neither part of one of the electric vehicles involved in the charging process nor of the charging cable. For example, a corresponding control unit is provided on-site in the form of a mobile device, such as a smartphone. "On-site" means, for example, that the communication connection between the control unit and the charging cable is a direct point-to-point connection, such as a wireless direct point-to-point connection, i.e., a connection without a forwarding intermediate station. For example, the wireless direct point-to-point connection is a point-to-point connection via Bluetooth. ®“Bluetooth” is a registered trademark (file numbers: 399078363, 399096027, 003502523) of Bluetooth SIG, Inc., Kirkland Wash., USA. The direct point-to-point connection can also be established, for example, using a cable-based communication cable, such as a USB cable, which is connected to both the control unit and the charging cable. Alternatively, the control unit can be provided on a remote server. “Remote” means, for example, that the communication connection between the control unit and the charging cable is a connection via an on-site intermediate station. This on-site intermediate station could be, for example, a mobile device or a second mobile device, such as a smartphone. The intermediate station forwards the communication between the control unit and the charging cable, for example, in both directions.The communication connection between the control unit and the charging cable comprises, for example, a direct point-to-point connection, such as a wireless direct point-to-point connection, between the intermediate station and the charging cable, i.e., a connection without an additional forwarding intermediate station. For example, the wireless direct point-to-point connection is a point-to-point connection via Bluetooth. ®For example, the direct point-to-point connection between the intermediate station and the charging cable is a wired point-to-point connection via a communication cable, such as a USB cable, which is connected to both the intermediate station and the charging cable. For example, the communication connection between the control unit and the charging cable comprises a communication connection between the intermediate station and the external control unit via a network, such as the Internet. At least in part, the network is a wireless network, such as a mobile network.

[0018] To transfer energy between two electric vehicles, the two electric vehicles are connected via a charging cable. Controlling the energy transfer via a charging cable between two electric vehicles using the external control unit makes it possible to reduce the number of electronics included in the charging cable for carrying out the charging process. In addition to energy transfer, the charging cable is configured to communicate with the external control unit. Furthermore, the charging cable is configured to control the energy transfer according to the control commands of the control unit. For example, the charging cable has circuits for controlling the transferred energy, such as a switch for closing and interrupting the energy transfer, a current limiter, and / or a current direction limiter.For example, the charging cable transmits information about the energy transfer to be carried out, such as the transmission current to be used, to the participating electric vehicles in accordance with the corresponding control commands, whose charging controllers carry out the energy transfer accordingly. The charging cable is configured symmetrically, for example, with regard to energy transfer and / or communication with the participating electric vehicles. For example, the charging cable has identical charging plugs at both ends. For example, the charging cable has an adapter at each end to which different charging plugs can be connected. For example, the charging cable is configured to transfer energy in both directions. Therefore, it makes no difference which end of the charging cable is connected to which of the electric vehicles. The current direction, for example, is controlled electronically in the charging cable.For example, the charging cable is configured to communicate with each of the connected electric vehicles in an identical manner.

[0019] For example, the charging cable is configured asymmetrically with regard to energy transmission and / or communication with the participating electric vehicles. In this case, the current direction is already determined by the charging cable. The charging cable is therefore configured, for example, to transmit energy only in a specific direction. The charging cable has a marking on each of its two charging plugs, indicating whether the corresponding charging plug should be connected to the electric vehicle receiving or supplying energy.

[0020] The external control unit comprises, for example, a user interface with an output device and / or an input device, which allows a user to monitor the energy transfer process and / or make adjustments. For example, the external control unit is provided in the form of a smartphone, which includes an application configured to control the charging process. An external control unit also enables control of the charging process that is independent of the on-board electronics of the participating electric vehicles. This can be particularly advantageous if energy is to be transferred between different types of electric vehicles.

[0021] For example, the control unit determines the smaller of the two maximum currents specified by the charging parameters as the transmission current to be used. One or both maximum currents can, for example, each be a maximum permissible current of the power transmission connection of the corresponding electric vehicle. This can, for example, ensure that the power transmission connections of the electric vehicles are not overloaded. This can be particularly advantageous if energy is to be transferred between different types of electric vehicles. One or both maximum currents can, for example, be a maximum current that has been set by the charging controls of the corresponding electric vehicle for power output or power reception.The first maximum current, which the first electric vehicle receiving the energy sets, defines, for example, a maximum current that the first electric vehicle agrees to receive. The second maximum current, which the second electric vehicle delivering the energy sets, defines, for example, a maximum current that the second electric vehicle agrees to deliver.

[0022] The two maximum currents are communicated by the electric vehicles, for example, via a basic signal via the charging cable and / or via high-level communication. For example, one or both electric vehicles communicate the respective maximum current in the form of a maximum permissible current during a basic signal. For example, one or both electric vehicles communicate a maximum permissible current during a basic signal and additionally the maximum currents for determining the transmission current for energy transmission during high-level communication. For example, the additionally communicated maximum currents are equal to or less than the maximum permissible currents.During high-level communication, for example, previously communicated maximum permissible currents can be confirmed or adjusted by additionally communicated maximum currents. For example, the maximum currents for determining the transmission current for energy transmission are communicated exclusively during high-level communication. The corresponding maximum currents can be, for example, maximum permissible currents or lower currents determined by the charging controllers of the respective electric vehicles.

[0023] Electric vehicles are understood here to be vehicles of any type that are powered by electrical energy, i.e., an electric drive. An electric drive is a drive with one or more electric motors that is controlled by a controller. An electric vehicle can be, for example, road vehicles or motor vehicles, rail vehicles, watercraft and / or aircraft, whose drive energy is provided in the form of electrical energy by one or more externally rechargeable energy storage devices in the vehicle. Such battery-powered vehicles are also referred to as battery electric vehicles. In particular, electric vehicles are purely electrically or hybrid-powered automobiles, i.e., electric cars or hybrid cars.Energy storage devices include rechargeable batteries, such as lithium-ion batteries, or capacitors, such as supercapacitors (“supercapacitors”) or ultracapacitors (“ultracapacitors”). Electric vehicles in this case can be purely electrically powered vehicles or hybrid vehicles, more specifically plug-in hybrid vehicles, which include an externally rechargeable energy storage unit or accumulator to provide electrical drive energy. Such plug-in hybrid vehicles include, in addition to an electric drive, one or more additional drives or energy converters that are powered by an energy source other than electricity.

[0024] Electric vehicles include, for example, electric motorcycles, such as small electric motorcycles, light electric vehicles, in particular light electric vehicles, neighborhood electric vehicles (NEVs), and low-speed electric vehicles (LEVs); electric motorcycles, in particular electric motorcycles, electric scooters; three-wheeled electric vehicles, in particular electric tricycles, electric trikes; and light four-wheeled electric vehicles, in particular medium-speed electric vehicles (MEVs). Furthermore, electric vehicles include, for example, electric passenger vehicles, such as electric cars, electric vehicles, and hybrid electric vehicles. Furthermore, electric vehicles include, for example, electric buses, such as battery buses and hybrid buses. Furthermore, electric vehicles include, for example, electric trucks and electric dump trucks.Electric vehicles also include, for example, electric boats, electric airplanes, electric drones, electric airships, and electric helicopters. Electric vehicles also include electric bicycles, electric wheelchairs, electric carts, electric golf carts, electric forklifts, driverless electric transport vehicles, and e-scooters.

[0025] A "processor" is understood here and below to mean a logic circuit that serves to execute program instructions. The logic circuit can be implemented on one or more discrete components, in particular on a chip. In particular, a "processor" is understood to mean a microprocessor or a microprocessor system comprising multiple processor cores and / or multiple microprocessors. Such a processor or microprocessor is implemented, for example, as a component of a microcomputer. In addition to the processor or microprocessor, the corresponding microcomputer comprises, for example, an internal bus, a memory and an interface(s) to one or more communication interfaces and / or to input / output (I / O).

[0026] A “module” here means an electronic circuit or circuit unit.

[0027] A “program” or “program instructions” is understood here, without limitation, to mean any type of program that includes machine-readable instructions for controlling a functionality of a processor.

[0028] A "communication interface" is understood here as an interface through which data can be received and sent. The communication interface can be configured for wireless radio-based communication or cable-based communication. Wireless communication can, for example, be implemented via WPAN (Wireless Personal Area Network), for example using Bluetooth. ® , or WLAN (Wireless Local Area Network). A wireless communication connection can be, for example, a wireless WPAN, e.g. Bluetooth ®-, or WLAN connection. A direct wireless communication connection can, for example, be a wireless point-to-point radio connection between two devices, in particular a point-to-point Bluetooth connection. In this case, one of the two devices acts as a "master" and the other as a "slave." For example, the two devices connected via a direct wireless communication connection form a piconet, i.e., a PAN of end devices that are connected via Bluetooth. ®are connected. A direct cable-based communication connection can, for example, be a cable-based point-to-point connection between two devices that are connected to each other via a communication cable connected to both devices. The communication cable can, for example, be a USB cable, in particular a USB cable with mini-USB connectors. For example, the control unit, e.g. in the form of a smartphone, and / or the charging cable can have a mini-USB port for connecting the USB cable with a mini-USB connector. In this case, one of the two devices acts as the "master" and the other as the "slave."

[0029] The term “memory” here refers to both volatile and non-volatile electronic memories or digital storage media. “Non-volatile memory” is understood here to be electronic memory for the permanent storage of data. Non-volatile memory can be configured as non-modifiable memory, also known as read-only memory (ROM), or as modifiable memory, also known as non-volatile memory (NVM). In particular, this can be an EEPROM, for example a flash EEPROM, known as flash for short. Non-volatile memory is characterized by the fact that the data stored on it is retained even after the power supply is switched off. “Volatile electronic memory” is understood here to be memory for the temporary storage of data, which is characterized in that all data is lost when the power supply is switched off.In particular, this can be a volatile direct access memory, also known as random-access memory (RAM), or a volatile main memory of the processor.

[0030] The charging cable is configured, for example, to conduct low-voltage communication with both electric vehicles, for example, to query charging parameters. Such communication, known as basic signaling (BS), is described, for example, in the international standard IEC 61851-1 of the International Electrotechnical Commission. According to IEC 61851-1, BS can be implemented, for example, via the CP (Control Pilot) and PP (Proximity Pilot) contacts of the charging cable in connection with the protective earth (PE).

[0031] Furthermore, the charging cable and / or the external control unit can be configured for communication with the electric vehicles at higher layers (High Level Communication / HLC). Such an HLC is described, for example, in the IEC 15118 international standards series of the International Electrotechnical Commission. This includes layers 2 to 7 according to ISO / IEC 15118-2 or, in the future, ISO / IEC 15118-20. The ISO / OSI reference model ("Open Systems Interconnection") is a reference model for open communication systems as a layered architecture published as a standard by the International Organization for Standardization (ISO). HLC with the electric vehicles via the charging cable can, for example, be implemented using Power Line Communication (PLC), as specified, for example, in the international standard IEC 15118-3 of the International Electrotechnical Commission.HLC between the external control unit and the electric vehicles can be implemented, for example, via direct wireless communication connections between the control unit and the respective electric vehicle, such as via Wi-Fi. For example, such HLC can be implemented as specified in the IEC 15118-8 standard.

[0032] The charging cable, for example, comprises two signal contacts on each side, i.e. pilot contact CP (“Control Pilot”) and proximity contact PP (“Proximity Pilot”). For example, a control unit of the charging cable supplies pilot contact CP with a square wave, for example a 1 kHz square wave with ±12 V, which is fed back by the electric vehicle via a resistor and a diode to the protective conductor PE. The charging cable or the control unit of the charging cable can communicate with the electric vehicle via pulse width modulation of the square wave. For example, predefined status queries and / or status information can be sent to the corresponding electric vehicle via this. For example, the electric vehicle can signal states to the charging cable via the resistor between CP and PE and, via this, to the external control unit, i.e. send status information.A signal from the proximity contact PP signals the charging cable that the corresponding electric vehicle is connected. For this purpose, a resistor is placed between PP and PE on the vehicle side, for example. By placing the resistor between PP and PE, the electric vehicle can signal to the charging cable, and through this to the external control unit, a maximum permissible current for delivering and / or receiving energy. This current is, for example, the physically maximum permissible current of the charging ports of the corresponding electric vehicles for delivering and / or receiving energy.

[0033] Embodiments enable a first purely electric or hybrid-powered electric vehicle to receive energy from a second purely electric or hybrid-powered electric vehicle, or the second electric vehicle to deliver energy to the first electric vehicle. A corresponding vehicle-to-vehicle energy transfer may be necessary, for example, if the first electric vehicle has broken down due to a lack of energy and there is no charging station nearby, for example. The second electric vehicle, which is intended to deliver energy, is configured to deliver energy.

[0034] To transfer energy from the second electric vehicle to the first electric vehicle, a system is used that includes a charging cable and an external control unit. A corresponding charging cable for transferring energy from the second electric vehicle to the first electric vehicle is also referred to below as an Active Charging Cable (ACC). A corresponding external control unit for controlling the energy transfer via the charging cable between the two electric vehicles is also referred to below as an Electric Vehicle to Electric Vehicle Charging Control Unit (EVEVCCU).

[0035] According to embodiments, the charging cable has a charging plug at each of two opposite ends. Each of the charging plugs is configured to establish a plug connection with a matching charging socket of one of the two electric vehicles concerned. For example, a control unit in the form of an embedded system is integrated into the cable, which independently controls signal and communication lines to both electric vehicles. Furthermore, the control unit is configured to communicate with the control unit using a communication interface for wireless and / or cable-based communication with the control unit, for example via Bluetooth. ®and / or USB cable. The charging cable further comprises one or more lines for the energy transfer between the two electric vehicles, which are, for example, connected directly to the contacts of the charging plugs. The corresponding lines are configured to establish an electrically conductive connection between the two electric vehicles. Alternatively, devices can optionally be integrated into the charging cable with which a direction of a current flow through the cable can be determined and the current strength of the current flow can be monitored and limited. The values ​​for the direction and current strength of the current flow include, for example, fixed values ​​and / or values ​​that can be set by the control unit. Furthermore, the charging cable comprises, for example, a switch with which the circuit for the current flow can be interrupted and closed.Furthermore, the charging cable comprises, for example, a device for continuously monitoring the continuity of a protective earthing conductor of the charging cable.

[0036] According to embodiments, the charging cable has, for example, a power supply, such as a low-voltage power supply, for the control unit and signal lines. The power supply is, for example, a rechargeable energy storage device. Optionally, the charging cable comprises a device with which the energy storage device, which is, for example, a rechargeable energy storage device, can be charged during energy transfer between the two electric vehicles. In addition, the charging cable has, for example, a switch with which the power supply to the control unit and signal lines can be switched on and off. Furthermore, the charging cable comprises, for example, a display device for displaying a current operating state of the charging cable.

[0037] For example, during a charging process between the two electric vehicles, a distinction is made between two phases: basic signaling (BS) for voltage-based communication and high-level communication (HLC). The BS, for example, is mandatory at the beginning, during, and at the end of a charging process. The HLC, for example, is also mandatory. For example, the HLC is optional. For example, the HLC is mandatory for the energy-supplying electric vehicle, while it is optional for the energy-receiving electric vehicle.

[0038] The BS is established, for example, via a CP contact (“Control Pilot”) and a PP contact (“Proximity Pilot”) of a charging plug of the charging cable in conjunction with a protective earth (PE). The PP contact is configured to detect the presence of the charging plug in an electric vehicle charging socket or the establishment of a connection between the charging plug and the charging socket. The CP contact is configured to transmit control signals between the charging cable and an electric vehicle. The protective earth for energy transmission and communication is a protective conductor designed to contact a protective contact of the connector.

[0039] The control unit in the charging cable controls the states and signals on the CP contacts at the request of the control unit. For example, the control unit controls pulse width modulation (PWM) used on the CP. Furthermore, the control unit detects states of the CP and PP contacts, which are influenced by a charging controller of the electric vehicle to which the corresponding charging plug is connected, and by the charging cable used. The detected states are sent by the control unit to the control unit as charging parameters in the course of status messages. Communication between the control unit of the charging cable and the control unit is, for example, wireless. For example, communication between the control unit of the charging cable and the control unit is cable-based.

[0040] According to embodiments, the BS between the control unit of the charging cable and the electric vehicles can be carried out via digital communication using LIN nodes (“Local Interconnect Network”) in the charging cable and the charging controllers of the electric vehicles.

[0041] For example, if a switch, a current direction limiter, a current limiter, and / or a monitoring unit are integrated into the charging cable, their states can also be retrieved and changed upon request from the control unit. For example, the charging cable detects their states and sends them to the control unit as charging parameters. For example, in response to the transmission of the corresponding states, the charging cable receives control commands from the control unit to change the states of the corresponding components, i.e., the switch, the current direction limiter, the current limiter, and / or the monitoring unit.

[0042] According to embodiments, the functionality of the communication between the control unit and the monitoring unit is continuously monitored. If the communication connection no longer functions, the components of the charging cable, for example, each transition to a safe default state or are set to a corresponding safe default state by the control unit of the charging cable.

[0043] According to embodiments, the control commands which the control unit sends to the control unit of the charging cable comprise a control command to set the PWM for one or both electric vehicles to 5%. Setting the PWM to 5% signals, for example, to the charging controller of the electric vehicle, which receives the 5% PWM, that further communication should take place between the charging controller of the corresponding electric vehicle and the control unit using the HLC. If the vehicle side, i.e. the control unit of the corresponding electric vehicle, signals that it is ready for communication using the HLC, this is reported to the control unit, for example via the control unit. Upon corresponding confirmation of the HLC communication by the charging controller of the corresponding electric vehicle, protocol units orProtocol elements that are exchanged within the HLC between the control unit and the charging controller of the corresponding electric vehicle, for example, transmitted via the control unit of the charging cable. For example, the protocol units are exchanged on the transmission link between the control unit and the corresponding electric vehicle using Power Line Communication (PLC) via the CP signal line. The control unit serves, for example, as a pass-through station for the protocol units of the HLC communication. HLC communication, for example, is communication on layers 2 to 7 of the ISO reference model. The ISO / OSI reference model (“Open Systems Interconnection”) defines a reference model for open communication systems as a layered architecture. This reference model is a reference model published as a standard by the International Organization for Standardization (ISO).

[0044] The control unit is a control unit that communicates wirelessly and / or via cable with the control unit in the charging cable. For example, the control unit in the charging cable controls the BS to the charging controllers in both electric vehicles. For example, the control unit carries out the BS communication with the charging controllers of both electric vehicles independently of each other. For example, the control unit communicates with both electric vehicles and queries charging parameters for each. Using the charging parameters provided by the two electric vehicles, the control unit plans the charging process, creates corresponding control commands for the control unit in the charging cable, and transmits them to the control unit.

[0045] In the case that both electric vehicles support HLC or are configured to run HLC, the control unit carries out the communication of layers 2 to 7 of the ISO reference model to the charging controllers of the two electric vehicles, for example, independently of each other. Protocol units are sent to and / or received from the control unit. The control unit receives the protocol units, for example, via a communication interface of the charging cable to wireless communication and performs a medium change for the protocol units from a wireless communication, for example, Bluetooth. ®, to a wired communication, for example, a Powerline Communication (PLC). Likewise, the control unit performs a medium change of the transmission medium for protocol units, which it receives from one of the charging controllers of the two electric vehicles. For example, during the HLC, the control unit receives protocol units via a wired communication, for example, a PLC, and forwards them via the Bluetooth ® , to the control unit.

[0046] The control unit behaves towards the energy-supplying electric vehicle, for example, like a control unit of a connection unit via which energy can be supplied to an energy grid. With the help of the BS and the HLC, if HLC, the control unit determines, for example, the possibilities and boundary conditions under which energy can be supplied by the energy-supplying electric vehicle on the one hand and under which energy can be received by the energy-receiving electric vehicle on the other. Thus, the charging parameters or boundary conditions for charging each of the two electric vehicles are initially determined.Using the received charging parameters, the control unit determines, for example, control parameters for controlling the charging process, which can ensure that the current intensity of the energy flow does not exceed the current absorption capacity of the charging electric vehicle. The control unit determines the corresponding control parameters and sends them, for example, to the two electric vehicles and to the control unit in the charging cable, which regulates and monitors the current flow between the two electric vehicles during the charging process. This ensures, for example, that a direct current flow from the energy-supplying electric vehicle to the energy-receiving electric vehicle can be enabled and activated without problems or danger.

[0047] According to embodiments, the control unit comprises, for example, one or more certificates and program instructions to support the HLC. Using the certificates, the control unit can, for example, authenticate itself to the two electric vehicles. The corresponding certificates are sent, for example, to the charging controllers of the two electric vehicles, which can authenticate the control unit using the corresponding certificates. For example, the control unit sends the certificates to each of the charging controllers of the two electric vehicles, i.e., authenticates itself to both electric vehicles. Using the program instructions, the control unit can, for example, execute cryptographic test protocols to check the validity of certificates of the charging controllers of the electric vehicles.Using the corresponding certificates that the control unit receives from the charging controllers of the two electric vehicles, the control unit can, for example, authenticate the two electric vehicles. For example, the control unit receives a certificate from each of the charging controllers of the two electric vehicles and authenticates both electric vehicles using the respective certificate. As a result, there is, for example, mutual authentication between the control unit and each of the two electric vehicles. In addition to the certificates and / or as part of the certificates, cryptographic keys can be exchanged between the control unit and the charging controllers of the electric vehicles. The corresponding cryptographic keys can, for example, be used to encrypt the data exchange between the control unit and the respective charging controllers of the two electric vehicles.For example, an encrypted communication channel is established between the control unit and the respective charging controller, in particular a communication channel encrypted using end-to-end encryption. The corresponding encryption can be symmetric, asymmetric, or hybrid encryption, for example. For example, the control unit and the charging controllers of the electric vehicles each have an asymmetric cryptographic key pair. These asymmetric cryptographic key pairs can be used, for example, to negotiate symmetric session keys. A Diffie-Hellman key exchange can be used for this purpose.

[0048] According to embodiments, the control unit comprises a user interface. The user interface comprises, for example, a display device, such as a display and / or indicators, for displaying current states and settings of the control unit, the charging cable, and / or the two electric vehicles. Furthermore, the user interface comprises, for example, an input device, such as a keyboard or a touchscreen function of the display, as an input option for controlling the charging process and for adjusting settings of the control unit and / or the charging cable. For example, the control unit is provided in the form of and / or as a component of a mobile device, such as a smartphone.

[0049] For example, a first electric vehicle A requires energy. The required energy is provided, for example, by a second electric vehicle B. During the charging process controlled by the external control unit, energy is to be transferred from electric vehicle B to electric vehicle A. For example, a driver of electric vehicle B gives his consent to the release of energy up to a certain amount. The driver of electric vehicle B gives this consent to the charging control of electric vehicle B, for example via the on-board electronics of electric vehicle B. For example, no further action is required on the part of a driver of electric vehicle A and, with the consent of the driver, the energy is transferred from electric vehicle B to electric vehicle A via the charging cable connected to both electric vehicles.For example, a further prerequisite for energy transfer is that the driver of electric vehicle A enables the electric vehicle A to charge energy to a selected extent, i.e., to a charging mode. For example, a further prerequisite for energy transfer is that the driver of electric vehicle A gives their consent to charging the energy to the specified extent. The driver of electric vehicle A gives this consent to the charging control system of electric vehicle A, for example, via the on-board electronics of electric vehicle A.

[0050] For both inputs, the circumstances under which energy is delivered or received are taken into account. For example, a private environment or a given exceptional situation is taken into account. This can simplify the HLC process, for example, by simplifying or skipping queries related to ensuring information security, data protection, and / or the billing process. For example, billing can be omitted. For example, the charging controllers of electric vehicles offer corresponding options.

[0051] Both electric vehicles are connected, for example, to the charging cable. Furthermore, a power supply for the charging cable is switched on, for example. The power supply for the charging cable is switched on, for example, using a switch included in the charging cable. The switching on of the power supply for the charging cable is indicated, for example, by an indicator device on the charging cable. For example, a green LED on the charging cable lights up to indicate that the power supply to the charging cable has been activated and the charging cable's control unit is ready, for example, to accept a communication request from the control unit.

[0052] The external control unit and the charging cable control unit connect, for example, via a wireless or cable-based communication link. The charging cable, for example, executes a BS with the electric vehicles and / or the two charging controllers of the electric vehicles. During the BS, a control unit of the charging cable receives charging parameters from both electric vehicles. The charging parameters indicate, for example, whether the electric vehicles are properly connected to the charging cable. Furthermore, the charging parameters include, for example, information about the maximum permissible charging currents of the charging ports of the two electric vehicles. The charging parameters include this information, for example, as maximum permissible currents or in addition to the maximum permissible currents.For example, the maximum currents that are equal to or lower than the maximum permissible specifications are later provided to the control unit as charging parameters, for example during an HLC. The external control unit receives the charging parameters determined from the charging cable using the BS. The external control unit sends a control command to the charging cable control unit, which sets a pulse width modulation (PWM) for both electric vehicles to a predefined low value, for example 5%. By setting the PWM to the predefined low value, the charging cable control unit requests the charging controllers of the two electric vehicles, for example, to initialize an HLC. The HLC of the charging controllers can, for example, be carried out using power line communication (PLC) with the charging cable control unit. The charging cable control unit forwards the communication, for example, to the external control unit.If both sides, ie both electric vehicles, signal their readiness for the HLC, the control unit reports a “ready” state of the charging controls of the electric vehicles with regard to the HLC to the external control unit.

[0053] If, for example, one of the electric vehicles does not accept the HLC, the system continues to use the BS, limiting communication to the BS and evaluating the available information about charging capacities. For example, energy delivery can only be activated if both electric vehicles have signaled their readiness to charge via the BS.

[0054] The current states of the vehicle charging controls of the two electric vehicles are provided, for example, on a display device of the external control unit, for example as part of a graphical user interface.

[0055] For example, if both electric vehicles are ready for an HLC, an independent HLC is started for each of the electric vehicles. For this purpose, a Layer 2 connection is initialized from the external control unit via the control unit and a PLC module of the charging cable assigned to the corresponding electric vehicle to the charging controller of the corresponding electric vehicle. Subsequently, further, higher-level protocols are activated. For example, the external control unit receives all information from electric vehicle B regarding its readiness to deliver energy, as well as the temporal and electrical constraints of an energy delivery, via an application protocol.Using the application protocol, the external control unit also signals to electric vehicle A that it is ready to deliver energy based on the parameters reported by electric vehicle B and waits for information from electric vehicle A regarding parameters regarding its energy acceptance. Based on the information from the charging controllers of both electric vehicles, the external control unit defines control parameters for controlling the energy delivery from electric vehicle B to electric vehicle A during the charging process. For example, both charging controllers define charging parameters that define a maximum current value for the energy transfer during the charging process for each electric vehicle.For example, the external control unit selects a smaller value of the two provided maximum values ​​as the control parameter and sends control commands to the electric vehicle charging controllers, which specify that the energy transfer must take place at a current according to the selected value. If the charging cable also has a current limiter, the external control unit, for example, sends the control command additionally and / or alternatively to the charging cable control unit. This selected value is agreed with electric vehicle B as the current of the energy to be transferred, and electric vehicle B starts delivering energy to the charging cable accordingly. Electric vehicle A is then signaled that it can begin receiving energy. It is also possible, for example, for electric vehicle A to already go into energy acceptance mode before electric vehicle B starts delivering energy.The charging cable's control unit receives the control command and, if necessary, uses the current limiter to limit the transmitted current to the maximum value specified in the control command for energy transmission during the charging process. For example, the current limiter is configured to monitor the energy transmission current. If the specified transmission current is exceeded, the current limiter interrupts the energy transmission, for example. This ensures that the transmitted current does not exceed the value selected by the external control unit, e.g., the maximum energy consumption value communicated by electric vehicle A.

[0056] If the charging cable further includes devices for limiting the direction of current flow, i.e., a current direction limiter, these are addressed by the external control unit via the charging cable's embedded control unit according to the agreed control parameters. If present, the control unit also closes a switch in the charging cable, for example, which closes a circuit between the two electric vehicles for transferring energy during the charging process. For example, the charging cable's control unit and / or the external control unit are configured to monitor the continuity of a protective earth of the charging cable, a current limit, and / or the closed circuits of the BS during the entire charging process.

[0057] When the charging process is complete, the external control unit sends a control command to the charging cable control unit to break the circuit between the two electric vehicles. Upon receiving the corresponding control command, the charging cable control unit opens the switch, if present, and thus breaks the circuit between the two electric vehicles. Furthermore, the external control unit, if used, terminates the HLC with both electric vehicles. In addition, the BS for both electric vehicles is reset to the initial state. For example, the circuit can be broken first and then the HLC terminated, or vice versa.

[0058] Depending on the design, there may be various options for completing or ending the charging process. For example, the charging process can be ended by a manual input from a user on the control unit. For example, upon receiving a corresponding input, the control unit sends information to the charging controllers of the two electric vehicles, informing them of the end of the charging process. Furthermore, the control unit sends, for example, a control command to the control unit of the charging cable to open a switch in the charging cable, thereby interrupting the electrical circuit between the two electric vehicles via the charging cable. Furthermore, at the instigation of the control unit, for example, the HLC is terminated and the BS is returned to the basic state.

[0059] For example, the charging process can be terminated manually on the charging cable, for example by activating a switch that interrupts the electrical circuit between the two electric vehicles via the charging cable. For example, the circuit is interrupted when a power supply, particularly a low-voltage power supply, is switched off on the charging cable. Such manual termination of the charging process on the charging cable can also serve as an emergency stop function to interrupt the charging process in an emergency situation.

[0060] For example, the charging process can be automatically terminated by the on-board electronics of one of the two electric vehicles, for example the second electric vehicle delivering energy or the first electric vehicle receiving energy, for example when a predetermined amount of energy has been transferred. Alternatively, the charging process can also be terminated, for example, by a manual input from the respective driver on the on-board electronics of the second electric vehicle delivering energy or the first electric vehicle receiving energy. If the initiative to terminate the charging process comes from the on-board electronics of one of the two electric vehicles, the termination includes, for example: sending information to the other party, iethe other electric vehicle, with which the other electric vehicle is informed of the end of the charging process; opening the switch in the charging cable, which interrupts the circuit between the two electric vehicles via the charging cable; shutting down the HLC, if the HLC is active, and setting the BS to the basic state. The opening of the switch and / or setting of the BS to the basic state can, for example, be initiated by the control unit of the charging cable. For example, informing the other party, opening the switch, shutting down the HLC and / or setting the BS to the basic state is initiated by the external control unit. For example, the external control unit of the on-board electronics of the electric vehicle, which initiates the termination of the charging process, is notified of the end of the charging process via the control unit of the charging cable or directly via HLC communication, e.g. via WLAN.The control unit then terminates the charging process for the other electric vehicle, for example, and initiates, via the charging cable's control unit, the opening of the switch in the charging cable, thereby breaking the circuit between the two electric vehicles via the charging cable. Furthermore, the control unit terminates the HLC, if the HLC is active, and initiates, via the charging cable's control unit, the return of the BS to the initial state.

[0061] According to embodiments, the control unit receives at least the first or second charging parameters from the control unit of the charging cable. Embodiments can have the advantage that the charging cable communicates with the electric vehicles involved in the charging process, for example, using BS. The charging parameters thus acquired are forwarded by the charging cable to the external control unit. For example, the external control unit can also query further charging parameters from the two electric vehicles via the charging cable using an HLC protocol. For this purpose, a control unit or the processor of the charging cable uses, for example, PLC via the charging cable.

[0062] According to embodiments, the charging cable further comprises a voltage-based communication unit for voltage-based communication with the two electric vehicles. The control unit of the charging cable determines at least the first or second charging parameters of the first or second electric vehicle using the voltage-based communication unit. Embodiments may have the advantage that the charging cable can, for example, perform signaling with the two electric vehicles using the voltage-based communication unit, such as BS using a CP and a PP signaling contact of the charging cable.

[0063] According to embodiments, the first communication connection is a direct wireless communication connection between the first communication interface of the control unit and the second communication interface of the charging cable. Embodiments may have the advantage that the external control unit, for example, has a direct wireless point-to-point communication connection, for example using Bluetooth. ® , to communicate with the charging cable. The external control unit can also communicate with the electric vehicles via the charging cable, for example, using a PLC.

[0064] According to embodiments, the first communication connection is a direct cable-based communication connection between the first communication interface of the control unit and the second communication interface of the charging cable. For example, the control unit is connected to the control unit of the charging cable using a communication cable, such as a USB cable, via which the corresponding direct cable-based communication connection is established. For example, the control unit is provided in the form of a mobile terminal, which is connected to the charging cable via the communication cable.

[0065] According to embodiments, the control unit further establishes a second wireless communication connection to the first electric vehicle. The control unit receives the first charging parameters from the first electric vehicle via the second communication connection. To establish the second wireless communication connection to the first electric vehicle, the control unit uses, for example, one or two further first communication interfaces. Embodiments can have the advantage that the external control unit can, for example, establish an additional communication connection to the first electric vehicle that is independent of the charging cable. This second communication connection is, for example, a direct wireless communication connection. For example, the second communication connection can be established using WLAN.For example, an HLC between the control unit and the first electric vehicle is carried out via the wireless communication connection, while a BS with the first electric vehicle is carried out via the charging cable, for example.

[0066] Alternatively, the second communication connection between the control unit and the first electric vehicle can be established, for example, via a second mobile device as an intermediate station, with which the control unit communicates in the form of a remote server via a wireless and / or wired network. Communication between the second mobile device and the first electric vehicle can be wireless. For example, the external control unit communicates with the corresponding mobile device via the Internet. For example, the external control unit communicates with the corresponding second mobile device at least partially via a cellular network.

[0067] The intermediate station, i.e., the second mobile device, communicates with the charging controllers of both electric vehicles, for example, wirelessly, such as via Wi-Fi, or via the charging cable's control unit. Communication with the charging cable's control unit can be wireless, such as via Bluetooth. ® , or cable-based, for example, via a communication cable. The communication cable, such as a USB cable, is connected to both the intermediate station and the charging cable. Communication between the charging cable's control unit and the vehicle's charging controllers then takes place via the charging cable, for example, using a PLC.

[0068] According to embodiments, the control unit further establishes a third wireless communication connection to the second electric vehicle. The control unit receives the second charging parameters from the second electric vehicle via the third communication connection. Embodiments can have the advantage that the external control unit can, for example, establish an additional communication connection to the second electric vehicle that is independent of the charging cable. This third communication connection is, for example, a direct wireless communication connection. For example, the third communication connection can be established using WLAN. For example, an HLC between the control unit and the second electric vehicle takes place via the third wireless communication connection. For example, a BS with the second electric vehicle takes place via the charging cable.

[0069] Alternatively, the third communication connection between the control unit and the second electric vehicle can be established, for example, via a mobile device, with which the control unit communicates in the form of a remote server via a wireless and / or wired network. Communication between the mobile device and the second electric vehicle can be wireless. For example, the external control unit communicates with the corresponding mobile device via the Internet. For example, the external control unit communicates with the corresponding mobile device at least partially via a cellular network.

[0070] According to embodiments, the control unit receives at least the first or second charging parameters as input via a user interface. Embodiments can have the advantage that, for example, no communication is necessary between the external control unit and the electric vehicles. The user interface is, for example, a user interface of the external control unit, which is provided, for example, in the form of a mobile terminal, such as a smartphone. Alternatively, the user interface can be a user interface of a mobile terminal, such as a smartphone, which is provided as an intermediate station for transmitting the communication between the external control unit and the charging cable. For example, the remote control unit is provided as a remote server.For example, the external control unit communicates with the corresponding mobile device via the Internet. For example, the external control unit communicates with the corresponding mobile device, at least partially, via a mobile network.

[0071] According to embodiments, the control unit is provided in the form of a first mobile terminal. The control unit can thus be provided in the form of and / or as a component of a mobile terminal, for example, a mobile, portable communications device such as a smartphone. For example, a smartphone provides the control unit, with the functionality of the control unit being programmed into an application and the required software being loaded onto the smartphone as an application (app). Embodiments can have the advantage that, for example, a smartphone can be used as an external control unit, on which an application for controlling the charging process is installed.

[0072] According to embodiments, the control unit establishes the first communication connection via a network comprising a second mobile device, via which the control unit receives the charging parameters. The second mobile device, such as a smartphone, serves as an intermediate station for forwarding the communication between the external control unit on the one hand and the charging cable and / or the two electric vehicles on the other hand. For example, the external control unit communicates with the corresponding second mobile device via the Internet. For example, the external control unit communicates with the corresponding second mobile device at least partially via a mobile radio network.Embodiments may have the advantage that the second mobile terminal, such as a smartphone, is used on site, and the control of the energy transfer process can be called up by the external control unit, for example via the Internet as a Software as a Service (SaaS).

[0073] According to embodiments, the control unit is provided in the form of a remote server. For example, the external control unit is a remote, i.e., remotely provided control unit. Thus, the external control unit is provided, for example, by a remote server or a central server. For example, an intermediate station is provided on-site near the charging cable and the electric vehicles involved in the charging process, which forwards the communication between the external, remote control unit and the electric vehicles and the charging cable. This intermediate station is, for example, a second mobile device.

[0074] According to embodiments, communication between the external control unit and the charging cable takes place via a network connection. For example, communication between the external control unit and the charging cable takes place via one or more intermediate stations. The corresponding intermediate stations are, for example, nodes of a network via which the external control unit communicates with the charging cable. For example, this makes it possible for the external control unit to control the charging process to not have to be in the immediate vicinity of the charging cable, as is the case with a Bluetooth ®-connection would be necessary. Instead, the external control unit can control the charging process from a remote location, for example. For example, the control unit is provided on a server. For example, the external control unit provides control of the charging process as a service accessible via a network. In this case, the server providing the external control unit is a service server.

[0075] In this case, in addition to the two electric vehicles, the charging cable, and the external control unit, one or more intermediate stations are used to carry out the charging process between the two electric vehicles. At least one of the intermediate stations is configured, for example, to communicate wirelessly with the charging cable or the charging cable's embedded control unit. Furthermore, one of the intermediate stations is configured, for example, to communicate wirelessly with the external control unit.

[0076] According to embodiments, communication between the external control unit and the charging controllers of the electric vehicles also takes place via a network connection. The corresponding communication between the external control unit and the charging controllers of the electric vehicles takes place, for example, via one or more intermediate stations. For example, the corresponding communication with the charging controllers takes place via the same intermediate stations as the communication between the external control unit and the charging cable. For example, one of the intermediate stations is configured to communicate wirelessly with the electric vehicles or their charging controllers.

[0077] If the intermediate stations receive protocol units during communication between the external control unit and one of the electric vehicle charging controllers and / or the charging cable, the intermediate station forwards the protocol unit to the corresponding charging controller and / or the charging cable or its embedded control unit according to an identifier of the protocol units. Conversely, protocol units, such as messages from the electric vehicle charging controllers and / or the embedded control unit of the charging cable, are forwarded to the external control unit via the one or more intermediate stations. This is also done, for example, using identifiers of the corresponding protocol units.

[0078] For example, a mobile device or a second mobile device, such as a smartphone, can be used as an on-site intermediate station at the charging cable. This second mobile device communicates, for example, with the charging cable and / or with one or both charging controllers of the two electric vehicles via a direct wireless communication connection. For example, the second mobile device communicates with the charging cable via a direct cable-based communication connection. For example, the mobile device used as an intermediate station communicates with the remote external control unit via a network connection. For example, the mobile device comprises an application configured to forward protocol units.

[0079] According to embodiments, first control instructions for controlling the energy transmission are further sent from the control unit to the first electric vehicle. The first control instructions include the specification of the transmission current to be used. According to embodiments, the first control instructions are sent via the first communication connection to the control unit of the charging cable for forwarding via the charging cable to the first electric vehicle. For example, the first control instructions are sent during the HLC, which is preceded, for example, by a BS. For example, the charging cable forwards the first control instructions to the first electric vehicle via PLC. According to embodiments, the first control instructions are sent to the first electric vehicle via the second wireless communication connection. For example, communication via the second wireless communication connection takes place using WLAN.

[0080] For example, the HLC between the external control unit and the charging controllers of the electric vehicles involved in the charging process does not take place via the charging cable. This means that the HLC does not take place via the embedded control unit of the charging cable or a PLC between the control unit and the charging controllers of the electric vehicles. Rather, the HLC takes place directly via wireless communication connections, e.g. using WLAN, between the external control unit and the respective charging controllers of the electric vehicles. The corresponding HLC can be carried out, for example, in accordance with ISO / IEC 15118-2 or the future ISO / IEC 15118-20. The WLAN connection can be established, for example, in accordance with ISO / IEC 15118-8. For example, the external control unit activates a WLAN base station ora Wi-Fi hotspot, after both electric vehicle charging controllers have confirmed via the charging cable using the BS that they are ready for a HLC and have signaled, for example, general charging parameters via the BS. The electric vehicle charging controllers connect to the external control unit via Wi-Fi. For example, such a connection requires the consent of the respective vehicle owner. The vehicle owners of the electric vehicles can signal their consent to the charging controller of the respective electric vehicle, for example, via the on-board electronics. Once the two charging controllers are connected to the external control unit via wireless communication links, the HLC communication is performed.If the charging cable is also configured to run an HLC, for example, using a PLC, the external control unit initiates HLC communication, for example, via the charging cable using a PLC, if it does not detect a Wi-Fi connection to the vehicle charging controllers. To do this, the external control unit sends corresponding control commands to the charging cable's control unit.

[0081] For example, the external control unit communicates with the electric vehicle charging controllers exclusively via a wireless communication connection, such as Wi-Fi. For example, there is no communication between the charging cable control unit and the electric vehicles. For example, there is only limited communication between the charging cable control unit and the electric vehicles, with an evaluation of the respective PP signal from the charging cable. The PP signal indicates, for example, the physically maximum permissible current for the electric vehicles involved and / or signals that the cable is plugged in. For example, the electric vehicle charging controllers only start the HLC when they detect a corresponding predefined PWM from the control unit on CP, for example 5% PWM.Alternatively, for example, only signaling occurs via PP, and the charging controllers of the electric vehicle start the HLC automatically, for example via WLAN, without waiting for signaling via CP.

[0082] For example, the external control unit receives information which it receives in other embodiments via the charging cable by means of BS from the charging controllers of the electric vehicles, in this embodiment directly from the charging controller of the respective electric vehicle by means of HLC via the wireless connection, such as WLAN.

[0083] For example, there is no HLC communication with the electric vehicles, in particular no communication between the external control unit and the charging controllers of the electric vehicles. Furthermore, there is no communication between the charging cable control unit and the charging controllers of the electric vehicles. For example, communication between the charging cable control unit and the electric vehicles is limited to an evaluation of the PP signal. The PP signal indicates, for example, the physically maximum permissible current for the participating electric vehicles and / or signals that the cable is plugged in. For example, all charging parameters of the electric vehicles relevant to the charging process are made available to the external control unit via manual input.

[0084] According to a further embodiment, wireless communication takes place between the external control unit and the charging controllers of the two electric vehicles involved in the charging process, for example via WLAN. This involves, for example, direct communication in each case, in which the charging cable is not involved. Alternatively, the corresponding wireless communication between the control unit and charging devices takes place, for example, using communication mediated via the charging cable, in which an HLC via a wireless connection between the external control unit and the control unit of the charging cable coupled with the PLC between the control unit of the charging cable and the respective charging controllers of the electric vehicles via the charging cable. A BS, for example at the beginning of the charging process, during the charging process and / or at the end of the charging process, remains unaffected.In other words, a corresponding BS is established between the control unit of the charging cable and the charging controllers of the electric vehicles, with the control unit of the charging cable forwarding the results of the BS to the external control unit via the wireless connection.

[0085] If both electric vehicles communicate wirelessly directly with the external control unit, either a charging cable design configured to implement a PLC between the charging cable's control unit and the electric vehicle's charging controllers or a charging cable design not configured to implement a PLC between the charging cable's control unit and the electric vehicle's charging controllers can be used. For example, the external control unit first checks whether wireless communication with the charging controllers of the participating electric vehicles is possible. If so, communication takes place wirelessly, for example, via Wi-Fi.If this is not possible, for example, if a communication attempt fails, HLC is implemented via the wireless connection between the external control unit and the charging cable control unit, coupled with a PLC between the charging cable control unit and those charging controllers of the electric vehicles with which direct wireless communication is not possible. A PLC can thus be implemented via the charging cable, for example, with one of the two electric vehicles, while direct wireless communication is established with the second electric vehicle. A PLC can be implemented via the charging cable, for example, with both electric vehicles, or direct wireless communication can be established with both electric vehicles.

[0086] According to embodiments, mixed operation may also be possible, in which one of the two electric vehicles communicates wirelessly, for example via WLAN, with the external control unit, while the other of the two electric vehicles communicates with the external control unit via PLC via the charging cable.

[0087] According to a further embodiment, charging parameters of the electric vehicles involved in the charging process are transmitted via a wireless communication connection between the external control unit and the charging controllers of the two electric vehicles. For example, the external control unit queries the charging parameters from the charging controllers of the two electric vehicles via a wireless communication connection and receives responses to the queries containing the requested charging parameters via the wireless communication connections to the charging controllers of the two electric vehicles. For example, the charging cable only monitors via the BS whether the charging plugs have been successfully inserted.

[0088] According to a further embodiment, no charging parameters are transmitted by the participating electric vehicles to the control unit of the charging cable or the external control unit. For example, only wireless communication takes place between the external communication unit and the charging cable. For example, the external control unit receives all charging parameters of the two electric vehicles required for the charging process in the form of manual inputs. The corresponding manual inputs are received, for example, via a user interface, such as an input device, of the external control unit, for example in the form of a mobile device. Using the received charging parameters, the external control unit determines control parameters for controlling the charging process and sends them to the control unit of the charging cable.The charging cable's control unit uses the received control parameters, for example, to control the current flow between the two electric vehicles during the charging process. For this purpose, the control unit uses a current flow control module in the charging cable. For example, the charging cable uses the BS to monitor whether the charging plugs have been successfully plugged in.

[0089] According to embodiments, second control instructions for controlling the energy transfer are further sent from the control unit to the second electric vehicle. The second control instructions include the transmission current to be used. According to embodiments, the second control instructions are sent via the first communication connection to the control unit of the charging cable for forwarding via the charging cable to the second electric vehicle. For example, the charging cable forwards the second control instructions to the second electric vehicle via PLC. According to embodiments, the second control instructions are sent to the second electric vehicle via the third wireless communication connection. For example, communication via the third wireless communication connection takes place using WLAN.

[0090] The transmission current included in the second control instructions is, for example, a current value transmitted within the framework of the HLC.

[0091] For example, two phases can be distinguished here: In a first phase, a BS takes place, during which the control unit receives current strength information from both electric vehicles based on the PP signals of both electric vehicles. The control unit determines, for example, the smaller of the two maximum permissible current strengths and signals this value to both electric vehicles via CP. These values ​​of the maximum permissible current strengths as well as the signaled value are each determined by the electrical conditions, i.e. physically. In a second phase, for example, an HLC takes place. During the HLC, for example, there is another exchange of maximum current strengths, to which the two electric vehicles each agree at a logical level.From this, the control unit determines, for example, the smaller of the two maximum current strengths and communicates this value to both electric vehicles as the transmission current strength. The two transmitted maximum current strengths, to which the electric vehicles agree at the logical level, are each less than or equal to the physically maximum permissible current strength of the respective electric vehicle. For example, the two transmitted maximum current strengths, to which the electric vehicles agree at the logical level, are each less than or equal to the smaller of the two physically maximum permissible current strengths. The joint value negotiated at the logical level in the form of the transmission current strength is, for example, less than or equal to the smaller of the two physically maximum permissible current strengths.

[0092] According to embodiments, the charging cable further comprises a switch for closing and interrupting an electrically conductive connection for energy transfer between the two electric vehicles via the charging cable. The control commands include a first control command for closing the electrically conductive connection using the switch. Embodiments can have the advantage that by closing and interrupting the electrically conductive connection, the charging cable, and thus the external control unit controlling the charging cable, has control over the execution of the energy transfer.

[0093] According to embodiments, the charging cable further comprises a current limiter for limiting the current transmitted via the charging cable between the two electric vehicles. The control commands comprise a second control command for limiting the current of the transmitted current to the transmission current to be used, using the current limiter. Embodiments can have the advantage that, thanks to the current limiter, the charging cable, and thus the external control unit controlling the charging cable, has control over the current of the transmitted energy. Thus, the charging cable can ensure that the transmission current to be used is not exceeded during the energy transfer.

[0094] According to embodiments, the charging cable further comprises a current direction limiter for determining a transmission direction of the current transmitted between the two electric vehicles via the charging cable. The control commands comprise a third control command for determining the transmission direction from the second electric vehicle to the first electric vehicle using the current direction limiter. Embodiments can have the advantage that, thanks to the current direction limiter, the charging cable, and thus the external control unit controlling the charging cable, has control over the direction in which the energy is transmitted. Thus, the charging cable can ensure that the energy is transmitted in the correct direction and that the first electric vehicle to be charged actually receives energy and does not release any remaining energy.

[0095] According to embodiments, the control unit comprises a certificate. The control unit sends the certificate, for example, to the two electric vehicles for authentication. In this case, successful authentication of the control unit to the two electric vehicles can, for example, be a prerequisite for executing the method for controlling the energy transfer between the two electric vehicles via the charging cable. Embodiments can have the advantage of ensuring that only an authorized control unit is enabled to control an energy transfer between the electric vehicles.

[0096] For example, the control unit also sends the certificate to the charging cable control unit for authentication. For example, successful authentication of the control unit with the charging cable control unit is also a prerequisite for executing the process for controlling the energy transfer between the two electric vehicles via the charging cable. For example, the control unit has appropriate cryptographic means to check the certificate and verify the authenticity of the control unit.

[0097] For example, in the course of setting up a wireless Bluetooth ®-Connection between the external control unit and the control unit of the charging cable requires a pairing between the control unit and the control unit. For example, the charging cable is assigned a fixed PIN, which must be provided to the control unit, for example via an input device, so that the control unit can use the Bluetooth ® -Connection to the charging cable or the charging cable's control unit. The corresponding PIN is provided, for example, by the charging cable, e.g., in the form of a print, embossing, or a display on a display device on the charging cable.

[0098] A "certificate" here refers to a digital certificate, such as a public-key certificate. A public-key certificate based on asymmetric cryptographic key pairs implements a so-called public-key infrastructure (PKI). A certificate is structured data used to assign a public cryptographic key of an asymmetric cryptosystem to an identity, such as a person or device. A certificate can, for example, contain a public cryptographic key and be signed. For example, the certificate can conform to the X.509 standard or another standard.

[0099] Digital certificates are a proven means of securing electronic communication using asymmetric cryptographic methods to assign a public cryptographic key (signature verification key) to an owner. The certificate documents the authenticity of the corresponding public cryptographic key and / or other properties / authorizations of the owner and is confirmed by an independent, trustworthy authority (certification service provider / CSP), generally the certification authority that issued the certificate. The certificate enables the verification of digital signatures generated as part of an authentication protocol, e.g., a challenge / response protocol, using the public key.

[0100] A certificate can be associated with a digital signature if the private cryptographic key associated with the public cryptographic key was used to generate the corresponding digital signature. By providing a certificate in association with a public cryptographic key, a CDA enables users of asymmetric cryptosystems to associate the corresponding public cryptographic key with an identity, for example, a person or a device. The public cryptographic key serves as a signature verification key, with which the validity of the corresponding signature can be verified. If a signature is valid, the successful validity check simultaneously proves its affiliation with the corresponding public cryptographic key or certificate and thus with the person or device to which the certificate is assigned.

[0101] Asymmetric cryptographic key pairs are used in a variety of cryptosystems and also play an important role in signing digital documents. An asymmetric cryptographic key pair consists of a public cryptographic key, which is used to encrypt data or verify signatures and may be shared with third parties, such as a service provider, and a private cryptographic key, which is used to decrypt data and create digital signatures and must generally be kept secret. The public cryptographic key allows anyone to encrypt data for the owner of the private cryptographic key, verify digital signatures on their documents, or authenticate them.A private cryptographic key allows its owner to decrypt data encrypted with the public cryptographic key or to create digital signatures. A signature created with a private cryptographic key can be verified with the corresponding public cryptographic key.

[0102] The creation of a digital signature, hereinafter referred to simply as a "signature," is a cryptographic process in which an additional data value, referred to as a "signature," is calculated for the data to be signed. The signature can, for example, be an encrypted hash value of the data to be signed, in particular a hash value encrypted with a private cryptographic key of an asymmetric cryptographic key pair associated with a certificate. The special feature of such a signature is that its authorship and affiliation with a specific person or device can be verified by any third party using the certificate.

[0103] For example, communication between the external control unit and the individual electric vehicles is encrypted. For example, communication between the external control unit and the charging cable is encrypted. For example, communication between the external control unit and an intermediate station is encrypted. The encryption can be symmetric encryption, asymmetric encryption, or hybrid encryption. For example, the encryption can be end-to-end encryption, which can be used to implement encrypted end-to-end connections.

[0104] An "encrypted end-to-end connection" is understood here to be a connection between a sender and a receiver with end-to-end encryption, in which data to be transmitted is encrypted by the original sender, e.g. the control unit or a charging controller of an electric vehicle, and only decrypted again by the final receiver, e.g. the charging controller of an electric vehicle or the control unit. The encryption of transmitted data thus takes place across all transmission stations, so that intermediate stations cannot gain any knowledge of the content of the transmitted data due to the encryption. The connection is secured using cryptographic methods, such as encryption and / or cryptographic check values, such as checksums, in order to prevent spying and / or undetectable manipulation of the transmission. A so-called secure messaging method can be used for this purpose.For example, end-to-end encryption is based on two symmetric cryptographic keys, with a first symmetric cryptographic key being used to encrypt messages and a second symmetric cryptographic key being used to authenticate the sender of the message and verify data integrity.

[0105] Embodiments further include a control unit for controlling energy transfer via a charging cable between two electric vehicles. The control unit includes a first processor, a first memory with first program instructions, and one or more first communication interfaces. The charging cable includes a control unit with a second processor and a second memory with second program instructions. Furthermore, the charging cable includes at least one second communication interface. Execution of the second program instructions by the second processor controls the charging cable at least to communicate via the second communication interface. The control unit is configured to control the energy transfer between the two electric vehicles via the charging cable upon execution of the first program instructions by the first processor.

[0106] Taxes include: Establishment of a first communication connection between the control unit and the control unit of the charging cable, Receiving one or more charging parameters of both electric vehicles by the control unit, wherein first charging parameters of the received charging parameters identify a first of the two electric vehicles as an electric vehicle to be received by energy and specify a first maximum current when receiving energy, wherein second charging parameters of the received charging parameters identify the second of the two electric vehicles as an electric vehicle delivering energy and specify a second maximum current when delivering energy, Determining a transmission current for the energy transfer from the second to the first electric vehicle using the first and second maximum currents by the control unit, Sending one or more control commands from the control unit to the control unit of the charging cable, wherein the control commands are configured, upon execution by the second processor, to control the energy transfer between the two electric vehicles, wherein the control commands include an indication of the transfer current to be used for the energy transfer from the second to the first electric vehicle via the charging cable.

[0107] According to embodiments, the control unit is configured to carry out each of the previously described embodiments of the method for controlling energy transfer via the charging cable between the two electric vehicles using the control unit.

[0108] According to embodiments, the control unit is a first mobile terminal.

[0109] According to embodiments, the control unit is a remote server. The first communication connection is a communication connection via a network to a second mobile device, via which the control unit receives the charging parameters.

[0110] Embodiments further include a system comprising a control unit according to one of the previously described embodiments and the charging cable, which comprises the control unit with the second processor and the second memory with the second program instructions as well as the second communication interface, wherein execution of the second program instructions by the second processor controls the charging cable at least for communication via the second communication interface.

[0111] According to embodiments, the system is configured to carry out each of the previously described embodiments of the method for controlling energy transfer via the charging cable between the two electric vehicles using the control unit.

[0112] According to embodiments, the control unit is a first mobile terminal.

[0113] According to embodiments, the control unit is a remote server. The first communication connection is a communication connection via a network to a second mobile device, via which the control unit receives the charging parameters. The system further comprises the second mobile device.

[0114] Embodiments of the invention will be explained in more detail below with reference to the drawings. They show: Fig. 1 a schematic block diagram of an exemplary charging cable for transferring energy between two electric vehicles, Fig. 2 a schematic block diagram of an exemplary control unit for controlling an energy transfer between two electric vehicles, Fig. 3 a schematic block diagram of an exemplary system for transferring energy between two electric vehicles, Fig. 4 a schematic block diagram of an exemplary system for transferring energy between two electric vehicles, Fig. 5 is a schematic block diagram of an exemplary system for transferring energy between two electric vehicles, Fig. 6 is a schematic block diagram of an exemplary system for transferring energy between two electric vehicles, Fig. 7 is a schematic block diagram of an exemplary system for transferring energy between two electric vehicles, Fig. 8 a schematic block diagram of an exemplary external control unit, Fig. 9 a schematic block diagram of an exemplary charging cable and Fig. 10 a schematic block diagram of an exemplary intermediate station.

[0115] Elements of the following embodiments that correspond to one another are identified by the same reference numerals.

[0116] Fig. 1 shows the structure of an exemplary charging cable or ACC 100, which is configured for energy transfer between two electric vehicles 300, 400. The energy transfer between two electric vehicles 300, 400 via the ACC 100 is controlled by an external control unit 200 or EVEVCCU. If energy transfer is to take place between the two electric vehicles 300, 400, a system comprising the ACC 100 and the control unit 200 is required, for example. The ACC 100 is configured so that energy transfer 604 is generally possible in both directions, i.e. from electric vehicle 300 to electric vehicle 400 as well as from electric vehicle 400 to electric vehicle 300. In other words, the ACC 100 is designed symmetrically with regard to its energy transfer capability, for example. For example, the ACC 100 is designed asymmetrically with regard to its energy transfer capability and specifies a transfer direction.Thus, two configurations of the ACC 100 are possible: The transmission direction can be adjustable via the EVEVCCU 200. In this case, the ACC 100 is designed symmetrically with regard to its energy transmission capability to enable energy transmission in both directions. Alternatively, the current flow direction from the ACC 100, and thus the energy transmission direction, can be fixed. In this case, the current flows through the ACC 100 from a source to the sink in only one direction. In this case, the ACC 100 would therefore be designed asymmetrically with regard to its energy transmission capability. In general, however, one of the two connected electric vehicles will require energy, and the second of the connected electric vehicles will have sufficient energy to be able to deliver energy.In the following, without restricting generality, the case in which the first electric vehicle 300 receives energy from the second electric vehicle 400 during the energy transfer is considered. In other words, the case of an energy transfer in the direction 602 is considered.

[0117] The ACC 100 is configured for a charging process between a first electric vehicle 300 participating in the charging process and a second electric vehicle 400 participating in the charging process. For example, the first electric vehicle 300 requires energy. During the charging process, energy is therefore to be transferred from the second electric vehicle 400 to the first electric vehicle 300 via the ACC 100.

[0118] The ACC 100 includes, for example, a switch 101, with which a power supply 111, more precisely a low-voltage power supply, for supplying a control unit 105 of the ACC 100 can be switched on and off. Furthermore, the switch 101 can also be used, for example, to switch power line communication modules 106, 107 and / or base signaling modules 108, 109 on and off. The low-voltage power supply is, for example, a 12 V power supply. Furthermore, the ACC 100 includes, for example, a display device 102 for displaying functional states of the ACC 100 and / or states of the charging process. Furthermore, the ACC 100 comprises, for example, a connection 103 for connecting a voltage, for example a low voltage, for charging the voltage supply 111. Optionally, batteries, in particular rechargeable batteries, could also be used to supply the ACC 100 with low voltage.In this case, the ACC 100 includes a battery compartment or a compartment for the power supply. Alternatively, capacitors, such as supercapacitors or ultracapacitors, can be used instead of batteries as energy storage for the low-voltage power supply.

[0119] Furthermore, the ACC 100 comprises, for example, a communication interface 104 for wireless communication with the EVEVCCU 200. The wireless communication between ACC 100 and EVEVCCU 200 via the communication interface 104 takes place, for example, by means of Bluetooth ® .

[0120] The control unit 105 of the ACC 100 comprises, for example, a processor and memory, perhaps as part of a microcomputer, with software, i.e., executable program instructions, which, when executed by the processor, are configured to control the control unit 105 such that it converts control commands received from the EVEVCCU 200 into corresponding actions. Furthermore, the program instructions are configured, when executed by the processor, to control the control unit 105 such that it forwards information or charging parameters, which the control unit 105 receives from the communication modules 106 to 109 for communication with the charging controllers of the electric vehicles 300, 400, to the EVEVCCU 200.

[0121] The ACC 100 includes, for example, a first power line communication (PLC) module 107, which is configured to transmit protocol units of a high-level communication (HLC) between the control unit 105 and the first electric vehicle 300. In addition, a first basic signaling module 109 is provided, for example, which is configured to execute basic signaling (BS) to the first electric vehicle 300. Furthermore, the module 109 can be configured to execute actions controlled by the control unit 105 and to signal evaluated states of the BS as sensor values ​​to the control unit 105.

[0122] Furthermore, the ACC 100 includes, for example, a second power line communication (PLC) module 106, which is configured to transmit protocol units of a high-level communication (HLC) between the control unit 105 and the second electric vehicle 400. In addition, a second basic signaling module 108 is provided, for example, which is configured to execute basic signaling (BS) to the second electric vehicle 400. Furthermore, the module 108 can be configured to execute actions controlled by the control unit 105 and to signal evaluated states of the BS as sensor values ​​to the control unit 105.

[0123] The ACC 100 can, for example, further comprise a current flow control module 110. The current flow control module 110 provides, for example, an optional circuit for controlling the current flow between the two electric vehicles 300, 400 via the ACC 100. For example, the current flow control module 110 is configured to limit the current, limit the direction of current flow, and / or switch the current flow. During current limitation, for example, the transmitted current intensity can be upper limited with a maximum value for the transmitted current intensity. During current flow direction limitation, for example, a flow direction of the current can be specified, i.e., a current flow between the electric vehicles 300, 400 in one direction can be enabled, while a current flow in the opposite direction is prevented.Furthermore, during switching of the current flow, the current flow between the two electric vehicles can be switched on and off, i.e., an electrically conductive connection for energy transmission between the two electric vehicles 300, 400 via the ACC 100 can be closed and then interrupted again. The corresponding settings of the current flow control module 110 are made, for example, by signaling the control unit 105, which executes control commands received, for example, from the EVEVCCU 200. The corresponding control commands define, for example, a current limit. Furthermore, the current flow control module 110 monitors, for example, a protective conductor of the ACC 100 and / or other units, which are defined, for example, by safety regulations.

[0124] Finally, the ACC 100 includes, for example, a power supply 111, in particular a low-voltage power supply, for operating the components of the ACC 100. These components require, for example, a low-voltage voltage. Furthermore, the ACC 100 includes, for example, an optional circuit 112 for charging the power supply 111 during the charging process by diverting a portion of the energy provided by the charging electric vehicle 400.

[0125] The control unit 105 of the ACC 100 includes, for example, software that converts control commands that the control unit 105 receives from the EVEVCCU 200 into corresponding actions, or converts information that the control unit 105 receives from the components 106 to 109 of the ACC into information to the EVEVCCU 200 and sends it.

[0126] The PLC module 106 is configured to transmit HLC protocol units via PLC between the control unit 105 of the ACC 100 and the electric vehicle 400 in both directions. The PLC module 107 is configured to transmit HLC protocol units via PLC between the control unit 105 of the ACC 100 and the electric vehicle 300 in both directions. The base signaling module 108 is configured to perform actions with a BS on the electric vehicle 400 according to the control by the control unit 105 of the ACC 100, to evaluate states of the BS, and to signal them as sensor values ​​to the control unit 105 of the ACC 100. The base signaling module 108 can also be replaced and / or supplemented, for example, by a LIN node.The basic signaling module 109 is configured to perform actions with the electric vehicle 300 according to the control by the control unit 105 of the ACC 100, to evaluate the states of the BS, and to signal them as sensor values ​​to the control unit 105 of the ACC 100. The basic signaling module 109 can, for example, also be replaced and / or supplemented by a LIN node. The current flow control module 110 comprises circuits for controlling and monitoring the current flow between the two electric vehicles 300, 400 involved in the charging process, which are connected to each other via the ACC 100. For example, the current flow control module 110 is configured to limit the current, to limit the current flow direction, to switch the conductive connection between the two electric vehicles 300, 400 via the ACC, to monitor the current limitation, and to monitor the continuity of the protective earth.For this purpose, the current flow control module 110 comprises, for example, a current limiter, a current direction limiter and / or a switch.

[0127] Settings of the current flow control module 110 are made, for example, by signaling from the control unit 105 of the ACC 100. The power supply 111 of the ACC 100 includes, for example, an energy storage device for the components of 100 that require a low voltage. The circuit 112 can be configured to charge the energy storage device of the power supply 111 during the charging process between the two electric vehicles 300, 400.

[0128] Fig. Figure 2 shows a schematic representation of an exemplary EVEVCCU 200, which is provided, for example, in the form of a mobile terminal 209, such as a smartphone. The EVEVCCU 200 comprises a user interface 201, which comprises, for example, a display device and an input device. A graphical user interface for operating the EVEVCCU 200 and, in particular, for controlling the charging process with the EVEVCCU 200 is displayed on the display device.

[0129] The EVEVCCU 200 further comprises a charging control module 202 for controlling the charging process between two electric vehicles. The charging control module 202 communicates with the charging controller of the first electric vehicle 300 and with the charging controller of the second electric vehicle 400. The charging control module 202 is configured to control the charging process in such a way that a problem-free and safe charging process from one electric vehicle to the other electric vehicle is enabled, particularly for the two electric vehicles involved. To this end, the charging control module 202 controls, for example, an optional current flow control module 110 of the ACC 100. The EVEVCCU 200 further comprises, for example, a first HLC component 203 for processing the protocols of layers 2 to 7 during communication between the charging control module 202 and the charging controller of the electric vehicle 400, for example via service primitives such as commands and messages.Furthermore, the EVEVCCU 200 comprises, for example, a first BS communication component 204 for communicating with the control unit of the ACC 100, which determines and reports the operations of the base signaling module to the BS with the electric vehicle 400, for example, via service primitives such as commands and messages. Furthermore, the EVEVCCU 200 comprises, for example, a charging cable communication component 205, which is configured to control the current flow in the ACC 100 if the ACC 100 comprises a current flow control module 110 with a circuit for controlling the current flow, and for communicating with the charging control module 202, for example, via service primitives such as commands and messages. The charging cable communication component 205 serves, for example, to configure, monitor, and / or manage the charging control module 202.

[0130] The EVEVCCU 200 also includes, for example, a second BS communication component 206 for communication with the control unit of the ACC 100, which determines and reports the processes of the basic signaling module to the BS with the electric vehicle 300, as well as for communication with the charging control module 202, for example via service primitives such as commands and messages. Furthermore, the EVEVCCU 200 includes, for example, a second HLC component 207 for processing the protocols of layers 2 to 7 during communication between the charging control module 202 and the charging controller of the electric vehicle 300, for example via service primitives such as commands and messages. Finally, the EVEVCCU 200 includes a communication interface 208 for communication with the ACC 100 via a communication interface 104 of the ACC 100.For example, communication between the EVEVCCU 200, for example in the form of a mobile terminal 209, and the ACC 100 is wireless communication. For example, communication between the EVEVCCU 200 and the ACC 100 is cable-based communication via a communication cable, for example a USB cable, which is connected to both the EVEVCCU 200, for example in the form of a mobile terminal 209, and the ACC 100.

[0131] The HLC component 203 is configured for an HLC, i.e. for handling protocols of layers 2 to 7 of ISO / IEC 15118-2 or the future ISO / IEC 15118-20, with the charging control of the electric vehicle 400. The HLC is carried out, for example, via the communication interface 208, the communication interface 104, the control unit 105 and the PLC module 106. The basic signaling component 204 is configured to communicate with the control unit 105 of the ACC 100, which controls the BS module 108 and reports its states, for example, via the communication interface 208 of the EVEVCCU and the communication interface 104 of the ACC 100. The charging cable communication component 205 is configured to communicate with the control unit 105 of the ACC 100 for Active Cable Control, i.e. for controlling the current flow via the ACC 100 for querying system statuses of the ACC 100.The charging cable communication component 205 communicates with the control unit 105 of the ACC 100, for example, via the communication interface 208 of the EVEVCCU and the communication interface 104 of the ACC 100. The base signaling component 206 is configured to communicate with the control unit 105 of the ACC 100, which controls the base signaling module 109 and reports its states. The communication of the base signaling component 206 with the control unit 105 of the ACC 100 occurs, for example, via the communication interface 208 of the EVEVCCU and the communication interface 104 of the ACC 100.

[0132] The HLC component 207 is configured for an HLC, i.e., for handling protocols of layers 2 to 7 of ISO / IEC 15118-2 or the future ISO / IEC 15118-20, with the charging controller of the electric vehicle 300. The HLC is implemented, for example, via the communication interface 208, the communication interface 104, the control unit 105, and the PLC module 107.

[0133] For example, the EVEVCCU 200 is implemented in a mobile terminal 209, such as a smartphone, which provides hardware or a platform for controlling the charging process. In addition to the user interface 201 and the communication interface 208, the corresponding hardware includes, for example, a processor and a memory. For example, program instructions for execution by the processor are stored in the memory. The program instructions represent, for example, an application or app for controlling the charging process. For example, the program instructions implement a charging control module 202 for controlling the charging process via the ACC 100. Furthermore, the EVEVCCU 200 includes, for example, a certificate 210 for authenticating the EVEVCCU 200 to the two electric vehicles.Such a certificate 210 for authentication purposes may be required, for example, in the course of an HLC with the electric vehicles, which requires successful authentication of the EVEVCCU 200 by the corresponding electric vehicle.

[0134] Fig. Figure 3 shows an exemplary EVEVCCU 200 and an exemplary ACC 100 communicating with each other. The exemplary EVEVCCU 200 of the Fig. 3 corresponds, for example, to the exemplary EVEVCCU 200 of the Fig. 2. The exemplary ACC 100 of the Fig. 3 corresponds, for example, to the exemplary ACC 100 of the Fig. 1, wherein further exemplary details of the control unit 105 of the ACC 100 are shown. For communication with the other components 106, 107, 108, 109, 110 of the ACC 100, the control unit 105 comprises components 113, 114, 115, 116, 117 configured for this purpose. A power line communication component 113 of the control unit 105 is configured for an HLC, for example, via a PLC, with the charging controller 401 of the electric vehicle 400 via a PLC module 106 of the ACC 100 and a PLC module 402 of the electric vehicle 400.

[0135] Shown is a communication relationship between the EVEVCCU 200 and the two electric vehicles 300, 400 using PLC for HLC. The two electric vehicles 300, 400 each comprise a charging controller 301, 401 and a PLC module 302, 402 for the HLC of the charging controllers 301, 401.

[0136] A basic signaling component 114 of the control unit 105 is configured for communication with the charging controller 401 of the electric vehicle 400 via a BS module 108 of the ACC 100. A charging cable communication component 115 of the control unit 105 is configured to communicate with a power flow control module 110 of the ACC 100. Via the charging cable communication component 115, the control unit 105 is configured to control and monitor the power flow control module 110 and thus the power flow between the two electric vehicles via the ACC. A basic signaling component 116 of the control unit 105 is configured for a BS with the charging controller 301 of the electric vehicle 300 via a BS module 109 of the ACC 100. A power line communication component 117 of the control unit 105 is configured for an HLC, for example by means of a PLC, with the charging controller 301 of the electric vehicle 300 via a PLC module 107 of the ACC 100 and a PLC module 302 of the electric vehicle 300.

[0137] To control the charging process, basic signaling is carried out, for example, with the charging controller 401 of the second electric vehicle 400. For example, the signals from the BS of the second electric vehicle 400 are already present after the plug connection between the ACC 100 and the second electric vehicle 400 has been established. In this case, the PWM signal arrives, for example, on behalf of the BS component 114. The electric vehicle 400 is, for example, the electric vehicle that delivers energy during the charging process. For the BS, the EVEVCCU 200 uses, for example, the charging control module 202, which communicates with the control unit 105 of the ACC 100 via the basic signaling component 204 in order to carry out the BS with the charging controller 401 of the second electric vehicle 400. For this purpose, the control unit 105 of the ACC 100 communicates with the charging controller 401 of the second electric vehicle 400 via the basic signaling module 108 during the BS.The charging control module 202 receives information determined via the BS, such as the status of the charging controller 401 and the physically maximum permissible current load of the electric vehicle 400 during the charging process. Communication between the charging control module 202 of the EVEVCCU 200 and the charging controller 401 of the second electric vehicle 400 takes place via the BS component 204, the communication interface 208, the communication interface 104 of the ACC 100, the control unit 105, the BS component 114, and the BS module 108.

[0138] The charging control module 202 signals a PWM of, for example, 5% via the BS component 204, the communication interface 208, the communication interface 104, the control unit 105, the BS component 114, and the BS module 108. A PWM of 5% signals, for example, a request to the charging controller 401 of the second electric vehicle 400 to initialize an HLC. If the second charging controller 401 rejects this request via the BS module 108, the BS component 114, the control unit 105, the communication interface 104, the communication interface 208, and the BS component 204, only the information received from the BS from the second charging controller 401 is available to the charging control module 202 for the second electric vehicle 400. When an HLC is accepted by the second charging controller 401, the charging control module 202 issues a start command to the HLC component 203 of the EVEVCCU 200 to activate the HLC.The HLC between the charging control module 202 of the EVEVCCU 200 and the charging controller 401 of the second electric vehicle 400 is handled, for example, via the PLC component 203, the communication interface 208, the communication interface 104, the control unit 105, the PLC component 113, the PLC module 106, and the PLC module 402 of the second electric vehicle 400. The charging control module 202 receives, for example, information from the charging controller 401 of the second electric vehicle 400 regarding the possibilities and boundary conditions of a possible energy output by the second electric vehicle 400.

[0139] To control the charging process, basic signaling is also carried out, for example, with the charging controller 301 of the first electric vehicle 300. For example, the signals from the BS of the first electric vehicle 300 are already present after the plug connection between the ACC 100 and the first electric vehicle 300 has been established. In this case, the PWM signal arrives, for example, on behalf of the BS component 116. The electric vehicle 300 is, for example, the electric vehicle receiving energy during the charging process. For the BS, the EVEVCCU 200 uses, for example, the charging control module 202, which communicates with the control unit 105 of the ACC 100 via the basic signaling component 206 in order to carry out the BS with the charging controller 301 of the first electric vehicle 300. For this purpose, the control unit 105 of the ACC 100 communicates with the charging controller 301 of the first electric vehicle 300 via the basic signaling module 109 during the BS.The charging control module 202 receives information determined via the BS, such as the status of the charging controller 301 and the physically maximum permissible current load of the electric vehicle 300 during the charging process. Communication between the charging control module 202 of the EVEVCCU 200 and the charging controller 301 of the first electric vehicle 300 takes place via the BS component 206, the communication interface 208, the communication interface 104 of the ACC 100, the control unit 105, the BS component 116, and the BS module 109.

[0140] The charging control module 202 signals a PWM of, for example, 5% via the BS component 206, the communication interface 208, the communication interface 104, the control unit 105, the BS component 116, and the BS module 109. A PWM of 5% signals, for example, a request to the charging controller 301 of the first electric vehicle 300 to initialize an HLC. If the first charging controller 301 rejects this request via the BS module 109, the BS component 116, the control unit 105, the communication interface 104, the communication interface 208, and the BS component 206, only the information received from the BS from the first charging controller 301 is available to the charging control module 202 for the first electric vehicle 300. When an HLC is accepted by the first charging controller 301, the charging control module 202 issues a start command to the HLC component 207 of the EVEVCCU 200 to activate the HLC.The HLC between the charging control module 202 of the EVEVCCU 200 and the charging controller 301 of the first electric vehicle 300 is handled, for example, via the PLC component 207, the communication interface 208, the communication interface 104, the control unit 105, the PLC component 117, the PLC module 107, and the PLC module 302 of the first electric vehicle 300. The charging control module 202 receives, for example, information on the possibilities and boundary conditions of a possible energy consumption by the first electric vehicle 300 from the charging controller 301 of the first electric vehicle 300.

[0141] Based on the information available from the HLC and, if applicable, the BS with the first charging controller 301 of the first electric vehicle 300 and the second charging controller 401 of the second electric vehicle 400, the charging control module 202 calculates control parameters for controlling the maximum current flow from the second electric vehicle 400 to the first electric vehicle 300. The load caused by the current intensity transmitted during the charging process may, for example, not be greater than the smaller of the maximum values ​​for the respective maximum current intensity and, if applicable, the respective maximum permissible current intensity previously specified by the two electric vehicles during the HLC and, if applicable, BS. The charging control module 202 signals and communicates the selected value for the current intensity of the energy to be transmitted to the two charging controllers 301, 401. For example, the control parameters for the two electric vehicles orThe charging ports of both electric vehicles are each determined from the PP signals of the electric vehicles, and the smaller of the two physically maximum permissible currents is determined as a result. On an HLC basis, for example, the maximum currents to which the two electric vehicles are willing to accept are determined at the logical level, and a value for the current of the energy to be transferred is selected as a result of negotiation at the application level. This selected value is, for example, the smaller of the two maximum currents to which the electric vehicles are willing to accept.Furthermore, the charging control module 202 enables the flow of current between the two electric vehicles via the ACC 100, for example, via the charging cable communication component 205 of the EVEVCCU 200, the communication interface 208, the communication interface 104 of the ACC 100, the control unit 105, the charging cable communication component 115 of the ACC 100, and the current flow control module 110. A prerequisite for enabling the flow of current is, for example, that the charging controllers 301, 401 of the two electric vehicles 300, 400 have each entered a ready state and have reported this to the EVEVCCU 200 via the application protocol.

[0142] After completion of the charging process, which is reported to the EVEVCCU 200, for example, via BS and possibly HLC, all protocols of the HLC are cleared and the BS returns to the basic state.

[0143] Fig. 4 shows another exemplary embodiment of an ACC 100. In contrast to the ACC 100 from Fig. 3, for example, the ACC 100 is not configured for a PLC with the participating electric vehicles 300, 400. For example, compared to the ACC 100, the ACC 100 lacks the two PLC modules 106, 107, and the control unit 105 of the ACC 100 lacks the two PLC components 113, 117.

[0144] In the Fig. 4, the charging control module 202 of the EVEVCCU 200 handles the HLC with the charging controller 401 of the electric vehicle 400 not via the AC 100 by means of a PLC, but via a wireless communication connection, such as WLAN. For this purpose, the charging control module 202 uses the HLC component 203 and the communication interface 211 of the EVEVCCU 200, which establishes a wireless communication connection with the electric vehicle 400 via its communication interface 403. The EVEVCCU also establishes a wireless communication connection with the second electric vehicle 300 involved in the charging process or its charging controller 301 via the HLC component 207, the communication interface 212 and the communication interface 303 of the electric vehicle 300. In this case, both the Fig. 4 shown ACC 100 as well as the ACC 100 according to Fig. 3. The ACC 100 of the Fig. 4 differs from the ACC 100 according to Fig. 3, for example, only because the ACC 100 of the Fig. 4 does not include the two hardware-based PLC modules 106 and 107 together with the two associated software components of the control unit 105, i.e. the PLC components 113 and 117.

[0145] In case of use of an ACC 100 according to Fig. 3 is in Fig. 4 also a mixed configuration is possible, in which one of the two electric vehicles 300, 400 supports HLC with the EVEVCCU 200 via WLAN, while the other of the two electric vehicles 300, 400 communicates with the EVEVCCU 200 via the ACC 100 using PLC.

[0146] Further components which are not required for the communication relationships between the involved components, ie the electric vehicles 300, 400, the ACC 100 and the EVEVCCU 200, are described in Fig. 4 are not listed separately. Additional components can be, for example, Fig. 1 and Fig. 2 can be taken.

[0147] The two electric vehicles 300, 400 each comprise a communication interface 303, 403, which is configured for wireless communication with the EVEVCCU 200, for example in the form of a mobile terminal. For wireless communication with the communication interfaces 303, 403 of the two electric vehicles 300, 400, the EVEVCCU 200 or the mobile terminal comprises, for example, a communication interface. This communication interface can, for example, be the same communication interface 208 via which the EVEVCCU 200 or the mobile terminal enables wireless communication with the ACC 100, or an additional communication interface. The communication interface of the EVEVCCU 200 for wireless communication with the communication interfaces 303, 403 of the two electric vehicles 300, 400 is, for example, a WLAN radio interface.For example, in addition to the communication interface 208 for wireless communication with the ACC 100, the EVEVCCU 200 comprises two additional communication interfaces 211, 212. A first communication interface 211 of these two additional communication interfaces 211, 212 is configured, for example, for wireless communication with the electric vehicle 400 or can be used for this purpose, while a second communication interface 212 is configured, for example, for wireless communication with the electric vehicle 400 or can be used for this purpose. The BS is carried out in the case of the in . Fig. 4, while an HLC is carried out directly between the EVEVCCU 200 and the two electric vehicles 300, 400. For example, instead of the ACC 100, the Fig. 4 also the ACC 100 of the Fig. 3 can be used. In the latter case, the two PLC modules 106, 107 and the two PLC components 113, 117 of the ACC 100 are not used if the EVEVCCU 200 uses direct wireless communication with the two electric vehicles 300, 400 to execute an HLC instead of a PLC provided by the ACC 100. If the ACC 100 is used, for example, a PLC can also be used via the ACC 100 with one of the two electric vehicles 300, 400, while direct wireless communication is established with the other of the two electric vehicles 300, 400, for example, according to IEC 15118-8.

[0148] Fig. 5 shows an exemplary ACC 100 in which the charging cable communication component 115 is configured, for example, only to determine whether the charging plugs at both ends of the ACC 100 are plugged into the charging sockets of the two electric vehicles 300, 400 and to establish the maximum permissible current of the charging point. Any further communication with the two electric vehicles 300, 400 takes place via a wireless communication connection between the EVEVCCU 200 and the charging controllers 301, 401 of the two electric vehicles 300, 400. Via the wireless communication connection, the charging controllers 301, 401 each communicate to the EVEVCCU 200, for example, the charging parameters of the corresponding electric vehicle 300, 400, which the EVEVCCU 200 uses to control the charging process.

[0149] For example, there is direct wireless communication, such as WLAN communication, between the EVEVCCU 200 and the charging controllers 301, 401 of the electric vehicles, as described in Fig. 4. For example, no BS is carried out via the ACC 100. In this case, the ACC 100 can be constructed without components 114, 116, 108, and 109 as shown in the figure. The evaluation of the proximity pilot or proximity contact is handled, for example, by the charging cable communication component 115.

[0150] Fig. 6 shows an exemplary embodiment of an ACC 100 that does not forward charging parameters of the participating electric vehicles 300, 400 to the EVEVCCU 200. For example, there is no wireless communication between the EVEVCCU 200 and the charging controllers 301, 401. For example, the EVEVECCU 200 only provides the user interface 201, the charging control module 202, and the communication interface 208 for communication with the ACC 100. The EVEVCCU can communicate with the ACC via the communication interface 208 and control the current flow during the charging process.

[0151] A communication connection is established, for example, only between the EVEVCCU 200 and the ACC 100. The EVEVCCU 200 receives charging parameters, for example, via manual inputs. For example, no communication takes place between the EVEVCCU 200 and the charging controllers 301, 401 of the two electric vehicles 300, 400. The EVEVCCU 200 uses the received charging parameters to determine control parameters for controlling the charging process. These control parameters are sent, for example, in the form of corresponding control commands using the communication interface 208 for wireless communication with the ACC 100 via the communication interface 104 to the control unit 105 of the ACC 100. The control unit 105 controls the current flow, for example, from the electric vehicle 400 to the electric vehicle 300, according to the received control commands. For this purpose, the control unit 105 uses, for example, the current flow control module 110 of the ACC 100.Furthermore, the control unit 105 uses, for example, the charging cable communication component 115 to determine, using the PP signals, whether the charging plugs at both ends of the ACC 100 have each been successfully plugged into the corresponding electric vehicle 300, 400. For example, confirmation by the charging cable communication component 115 that the charging plugs have each been successfully plugged in is a prerequisite for the control unit 105 to enable the energy transfer between the two electric vehicles 300, 400 via the ACC 100.

[0152] Fig. 7 shows an exemplary system for controlling a charging process using an intermediate station 500, for example in the form of a second mobile terminal 220. If an energy transfer between the two electric vehicles 300, 400 is to take place, the system used for this purpose comprises, in the case of Fig. 7, for example, in addition to the ACC 100 and the control unit 200, the intermediate station 500. The EVEVCCU 200 corresponds, for example, to the EVEVCCU 200 from Fig. 2. The ACC 100 corresponds, for example, to the AC 100 from Fig. 3. Alternatively, the ACC 100 could be the ACC 100 from Fig. 4 or the ACC 100 from Fig. 5. The EVEVCCU 200 communicates with the control unit of the ACC 100 and / or the charging controllers 301, 401 of the two electric vehicles 300, 400, for example, via an intermediate station 500. The corresponding intermediate station 500 can, for example, be provided in the form of a second mobile terminal 220, such as a smartphone. The EVEVCCU 200 is, for example, provided on a remote server, and its functionality can be called as a service by the mobile terminal 220 via a network. Communication between ACC 100 and EVEVCCU 200 can, for example, be analogous to the wireless communication between ACC 100 and EVEVCCU 200 of the Fig. 3, wherein the intermediate station 500, for example in the form of a smartphone, forwards the data transmitted between ACC 100 and EVEVCCU 200. For example, as in Fig. 3, all communication between the EVEVCCU 200 and the charging controllers 301, 401 of the electric vehicles 300, 400 via the ACC 100. The transmitted data can be, for example, data resulting from the BS and / or data from an HLC.

[0153] Protocol units that the intermediate station 500 receives from the HLC component 203 or 207 of the EVEVCCU 200 are forwarded by the HLC component via a wireless communication connection, such as WLAN, to the communication interface 403 or 303 of the electric vehicle 400 or 300 for which they are intended. If there is no direct wireless communication connection between the intermediate station 500 and the charging controllers 301, 401 of the electric vehicles 300, 400, communication with the corresponding charging controller(s) 301, 401 takes place, for example, via the control unit 105 in the ACC 100, which sends the communication to the designated charging controller 301, 401, for example, via PLC.Conversely, if there is no communication connection with the corresponding charging controller(s) 301, 401 via the control unit 105 in the ACC 100, communication takes place, for example, via a direct wireless communication connection between the intermediate station 500 and the charging controllers 301, 401 of the electric vehicles 300, 400.

[0154] Protocol units which the intermediate station 500 receives from the base signaling component 204 or 206 are forwarded by the intermediate station 500 to the control unit 105 in the ACC 100, which converts the received protocol units into corresponding signals from the BS to the intended charging controller 401 or 4301 of the electric vehicles 400 or 300.

[0155] Protocol units that the intermediate station 500 receives from the charging cable communication component 205 are forwarded by the intermediate station 500 to the control unit 105 in the ACC 100, which implements the received protocol units for actions for power flow control using the power flow control module and for managing and controlling the control unit 105.

[0156] Communication between ACC 100 and EVEVCCU 200 can be analogous to the wireless communication between ACC 100 and EVEVCCU 200 of the Fig. 4 or Fig. 5, wherein the intermediate station 500, for example in the form of a smartphone, forwards the data transmitted between ACC 100 and EVEVCCU 200. Communication between the charging controllers 301, 401 of the electric vehicles 300, 400 and the EVEVCCU 200 can, for example, be analogous to the wireless communication between the charging controllers 301, 401 of the electric vehicles 300, 400 and the EVEVCCU 200 of the Fig. 4 or Fig. 5, wherein the intermediate station 500, for example in the form of a smartphone, forwards the data transmitted between the charging controllers 301, 401 of the electric vehicles 300, 400 and the EVEVCCU 200. In particular, the communication can comprise direct wireless communication between the charging controllers 301, 401 of the electric vehicles 300, 400 and the intermediate station 500. For example, the communication can also comprise direct cable-based communication between the charging controllers 301, 401 of the electric vehicles 300, 400 and the intermediate station 500.

[0157] Communication between ACC 100 and EVEVCCU 200 can be analogous to the wireless communication between ACC 100 and EVEVCCU 200 of the Fig. 6 for transmitting the control commands from the EVEVCCU 200 to the control unit 105 of the ACC 100, wherein the intermediate station 500, for example in the form of a smartphone, forwards the data transmitted between ACC 100 and EVEVCCU 200. For example, in the case of Fig. 7 the mobile terminal 220 used as intermediate station 500 receives a manual input with the charging parameters of the two electric vehicles 300, 400 via an input device, which the intermediate station 500 forwards to the EVEVCCU 200 for determining the control parameters to be used for the charging process and for generating the control commands.

[0158] Fig. 8 shows an exemplary external control unit 200. The external control unit 200 is implemented, for example, in the form of a mobile device, such as a smartphone, or, for example, in the form of a remote server. The external control unit 200 comprises a processor 234, a memory 230 with program instructions 236, and a communication interface 208. The control unit 200 is configured, upon execution of the program instructions 236 by the processor 234, to control an energy transfer between two electric vehicles via the charging cable. For example, the program instructions 236 comprise program instructions of an application installed on the control unit 200, which, for example, implements a charging control module. Furthermore, the application implements, for example, a control of the BS and / or protocols of the HLC.

[0159] The communication interface 208 is configured to establish a communication connection to a charging cable. This communication connection can, for example, be one for establishing a direct wireless point-to-point connection between the control unit 200 and the charging cable. For example, the communication interface 208 of the control unit 200 is configured to use a Bluetooth ®-Connection to the charging cable. The communication connection can alternatively be a cable-based communication connection, which is established via a communication cable, such as a USB cable, which is connected to the communication interface 208 and a communication interface of the charging cable. The communication connection can alternatively be a communication connection via a network. For example, the control unit is implemented in the form of a remote server which communicates via a network with a mobile terminal on site. A second mobile terminal on site forwards, for example, control commands from the control unit 200 to the control unit of the charging cable and information from the charging cable to the control unit 200. In addition, the communication interface 208 can be configured to communicate with the electric vehicles involved in the energy transmission.For example, the control unit 200 comprises one or more additional physical communication interfaces (not shown), e.g., WLAN interfaces, for communication with the electric vehicles. For communication via the one or more physical communication interfaces such as 208, the control unit 200 comprises one or more software components that form logical communication interfaces and implement communication protocols for communication via the one or more physical communication interfaces of the control unit 200. These logical communication interfaces or components comprise, for example, one or more high-level communication components, one or more basic signaling components, and / or a charging cable communication component. For example, the control unit 200 comprises at least five logical communication interfaces, ietwo high-level communication components, two basic signaling components, and one charging cable communication component. For example, instructions 236 provide the corresponding software for the logical communication interfaces, e.g., the corresponding communication protocols. Furthermore, instructions 236 include, for example, software for controlling the one or more physical communication interfaces of control unit 200.

[0160] The control unit 200 further comprises a user interface 201. The user interface 201 comprises, for example, an output device, such as a display, and an input device, such as a keyboard. The output and input devices can also be combined, for example in the form of a touch display. The user interface 201 enables a user of the control unit 200 to monitor the progress of the energy transfer and its boundary conditions and to adjust them if necessary. For example, the user of the control unit 200 can specify charging parameters for the charging process via the user interface 201. For example, the instructions 236 provide software for controlling the user interface 201 of the control unit 200.

[0161] For example, the control unit further comprises a certificate 210 for authentication to the electric vehicles and / or to the charging cable. The certificate 210, for example, verifies authorization of the control unit 200 to control the energy transfer between the two electric vehicles via the charging cable. For example, the certificate 210 comprises a public cryptographic key of the control unit 200. This public cryptographic key can serve, for example, as a signature verification key for verifying a signature of the control unit 200, which was created with a private cryptographic key 232 associated with the public cryptographic key of the certificate 200. By providing appropriately signed data, the control unit 200 can verify the ownership of the private cryptographic key, whereby the certificate 210 and the authorization granted by the certificate 210 can be assigned to it.For example, the communication between the control unit 200 and the electric vehicles and / or the charging cable is encrypted, for example using a symmetric session key. Furthermore, communication between the control unit 200 and an on-site intermediate station can also be encrypted, for example using TLS and / or HTTPS.

[0162] Fig. 9 shows an exemplary charging cable 100. The charging cable 100 includes, among other things, a control unit 105. The control unit 105 includes, for example, a processor 122 and a memory 120 with program instructions 124. The control unit 105 is configured to control the functions of the charging cable 100. For this purpose, the program instructions 124 include, for example, software for controlling the control unit 105 or for implementing the functionalities of the control unit 105. Upon execution of the program instructions 124 by the processor 122, the control unit 105 carries out communication with the electric vehicles for an external control unit or forwards data from the corresponding communication between the electric vehicles and the external control unit. Furthermore, the control unit 105 can be configured to control the energy transfer between the two electric vehicles via the charging cable according to control commands from the control unit.For example, the control unit 105, if present, can control a switch for closing and breaking an electrically conductive connection between the two electric vehicles, a current limiter for limiting the current transmitted between the electric vehicles and / or a current direction limiter for limiting the direction of transmission of the current between the two electric vehicles according to the control commands of the control unit.

[0163] The program instructions 124 further provide software for controlling the charging cable hardware, for example, for controlling power line communication modules, base signaling modules, a current flow control module, a switch, a display device, and / or a voltage supply. Furthermore, the program instructions 124 implement one or more software components for communicating with a control unit and with charging controllers of electric vehicles involved in the charging process. These software components form logical communication interfaces and implement communication protocols for communicating with the control unit and with the charging controllers of electric vehicles. These logical communication interfaces or components include, for example, one or more power line communication modules, one or more base signaling components, and / or a charging cable communication component.

[0164] Furthermore, the charging cable 100 comprises a communication interface 104 configured for communication with the control unit or an intermediate station, which forwards a data exchange between the charging cable and the control unit. The communication connection established by the communication interface 104 to the control unit or intermediate station is, for example, a direct wireless point-to-point connection, such as a Bluetooth ® -Connection. Furthermore, the charging cable includes additional physical interfaces for connecting to the electric vehicle in the form of charging plugs, each of which includes, for example, a CP contact and a PP contact, as well as contacts for energy transmission, such as a PE contact and contacts for transmitting AC or DC.

[0165] Fig.10 shows an exemplary intermediate station 500. The intermediate station 500 is provided, for example, in the form of a mobile device, such as a smartphone. The intermediate station 500 is configured to forward a data exchange between a control unit in the form of a remote server and a charging cable as well as the charging controllers of the electric vehicles. For this purpose, the intermediate station 500 has one or more communication interfaces 514. The communication interfaces 514 are configured, for example, to provide a direct wireless communication connection, for example, using Bluetooth. ®, between intermediate station 500 and the charging cable. This communication connection is, for example, a point-to-point connection. Furthermore, communication interfaces 514 are configured, for example, to communicate with the external control unit, for example in the form of a remote server, via a network. The corresponding network is, for example, a wired and / or wireless network. For example, the network comprises a cellular network. For example, the communication takes place via a public network, such as the Internet. Furthermore, the communication between intermediate station 500 and the control unit can be authentic and encrypted, for example using TLS and / or HTTPS.For authentication to the external control unit, the charging cable, and / or the electric vehicles, the intermediate station 500 comprises, for example, one or more cryptographic keys 506. The cryptographic keys 506 are, for example, an asymmetric key pair with a private cryptographic key and a public cryptographic key. For example, the public cryptographic key of the asymmetric key pair can be provided as part of a certificate of the intermediate station 500.

[0166] In addition, the intermediate station 500 can be configured with the communication interfaces 514 to establish wireless communication connections to the electric vehicles. These are, for example, wireless communication connections using WLAN. These are, for example, direct wireless point-to-point connections to the respective electric vehicles, for example via Bluetooth. ® . Communication between the intermediate station 500 and the charging cable and / or the electric vehicles can also be encrypted, for example using symmetric session keys.

[0167] In addition to the communication interfaces 514, the intermediate station 500 comprises a processor 508 and a memory 502 with program instructions 510. The intermediate station 500 is configured, upon execution of the program instructions 510 by the processor 508, to initiate communication for controlling an energy transfer between two electric vehicles via the charging cable between an external control unit, such as a remote server, on the one hand, and the charging cable and / or the electric vehicles on the other. For example, the program instructions 512 comprise program instructions of an application installed on the intermediate station 500, which enables access to the remote server and the functions provided by it for controlling the energy transfer. For example, the application is a browser that enables access to the remote server via the Internet.

[0168] Finally, the intermediate station 500 also includes, for example, a user interface 512. The user interface 512 includes, for example, an output device, such as a display, and an input device, such as a keyboard. The output and input devices can also be combined, for example in the form of a touch display. The user interface 512 enables a user of the intermediate station 500 to initiate the energy transfer process, monitor its progress, and make and terminate adjustments if necessary. For example, the user of the external control unit can specify charging parameters for the charging process via the user interface 512 of the intermediate station 500, which the intermediate station 500 forwards to the control unit. List of reference symbols 100 charging cables 101 switches 102 Display device 103 Charging socket 104 Communication interface 105 Control unit 106 Power Line Communication Module 107 Power Line Communication Module 108 Basic signaling module 109 Basic signaling module 110 Current flow control module 111 Power supply 112 switches 113 Power Line Communication Component 114 Basic signaling component 115 Charging cable communication component 116 Basic signaling component 117 Power Line Communication Component 120 memory 122 processor 124 program instructions 200 control unit 201 User interface 202 Charging control module 203 high-level communication component 204 Basic signaling component 205 Charging cable communication component 206 Basic signaling component 207 high-level communication component 208 Communication interface 209 mobile devices 210 Certificate 211 Communication interface 212 Communication interface 220 mobile devices 230 storage 232 cryptographic key 234 processor 236 program instructions 300 electric vehicles 301 Charging control 302 power line communication module 303 Communication interface 400 electric vehicles 401 Charging control 402 power line communication module 403 Communication interface 500 intermediate station 502 memory 506 cryptographic keys 508 processor 510 instructions 512 User interface 514 Communication interface 600 system 602 Direction of current flow 604 current flow directions

Claims

[1] Method for controlling an energy transfer via a charging cable (100) between two electric vehicles (300, 400) using an external control unit (200), wherein the control unit (200) comprises a first processor (234), a first memory (230) with first program instructions (236) and one or more first communication interfaces (208, 211, 212), wherein the charging cable (100) comprises a control unit (105) with a second processor (122) and a second memory (120) with second program instructions (124), wherein the charging cable (100) further comprises at least a second communication interface (104), wherein the execution of the second program instructions (124) by the second processor (122) controls the charging cable (100) to communicate at least via the second communication interface (104), wherein the control unit (200) is configured to execute a procedure for controlling the energy transfer between the two electric vehicles (300, 400) via the charging cable (100) upon execution of the first program instructions (236) by the first processor (234), the procedure includes: Establishment of an initial communication link between the control unit (200) and the control unit (105) of the charging cable (100), The control unit (200) receives one or more charging parameters from both electric vehicles (300, 400), wherein the first charging parameters of the received charging parameters identify the first of the two electric vehicles (300) as an electric vehicle to receive energy and specify a first maximum current when receiving energy, and wherein the second charging parameters of the received charging parameters identify the second of the two electric vehicles (400) as an electric vehicle supplying energy and specify a second maximum current when supplying energy. wherein the control unit (200) further establishes a second wireless communication link to the first electric vehicle (300), wherein the control unit (200) receives the first charging parameters from the first electric vehicle (300) via the second communication link, wherein the control unit (200) further establishes a third wireless communication link to the second electric vehicle (400), wherein the control unit (200) receives the second charging parameters from the second electric vehicle (400) via the third communication link, Determining a transmission current for the energy transfer from the second to the first electric vehicle (300, 400) using the first and second maximum currents by the control unit (200), which is passed on to the electric vehicles involved so that their charging controllers can carry out the energy transfer accordingly, Sending one or more control commands from the control unit (200) to the control unit (105) of the charging cable (100), wherein the control commands are configured to control, upon execution by the second processor, the energy transfer between the two electric vehicles (300, 400), wherein the control commands include a specification of the transmission current to be used for the energy transfer from the second to the first electric vehicle (300, 400) via the charging cable (100). [2] Method according to claim 1, wherein the first communication link is a direct wireless or cable-based communication link between the first communication interface (208) of the control unit (200) and the second communication interface (104) of the charging cable (100). [3] Method according to any of the preceding claims, wherein the control unit (200) is provided in the form of a mobile terminal (209). [4] Method according to one of the preceding claims, wherein first control instructions for controlling the energy transmission are sent from the control unit (200) to the first electric vehicle (300), the first control instructions comprising the specification of the transmission current to be used. [5] Method according to claim 4, wherein the first control instructions are sent via the first communication link to the control unit (105) of the charging cable (100) for forwarding via the charging cable (100) to the first electric vehicle (300) or wherein the first control instructions are sent via the second wireless communication link to the first electric vehicle (300). [6] Method according to one of the preceding claims, wherein furthermore second control instructions for controlling the energy transfer from the control unit (200) to the second electric vehicle (400) are sent, wherein the second control instructions include the transmission current to be used. [7] Method according to claim 6, wherein the second control instructions are sent via the first communication link to the control unit (105) of the charging cable (100) for forwarding via the charging cable (100) to the second electric vehicle (400) or wherein the second control instructions are sent via the third wireless communication link to the second electric vehicle (400). [8] Method according to one of the preceding claims, wherein the charging cable (100) further comprises a switch (112) for closing and interrupting an electrically conductive connection for energy transfer between the two electric vehicles (300, 400) via the charging cable (100), wherein the control commands comprise a first control command to close the electrically conductive connection using the switch (112). [9] Method according to one of the preceding claims, wherein the charging cable (100) further comprises a current limiter for limiting the current of the current transmitted via the charging cable (100) between the two electric vehicles (300, 400), wherein the control commands comprise a second control command for limiting the current of the transmitted current to the transmission current to be used by means of the current limiter. [10] Method according to one of the preceding claims, wherein the charging cable (100) further comprises a current direction limiter for determining a transmission direction of the current transmitted via the charging cable (100) between the two electric vehicles (300, 400), wherein the control commands comprise a third control command for determining the transmission direction from the second electric vehicle (400) to the first electric vehicle (300) using the current direction limiter. [11] Method according to any of the preceding claims, wherein the control unit (200) comprises a certificate (210), wherein the control unit (200) sends the certificate (210) to the two electric vehicles (300, 400) for authentication, wherein successful authentication of the control unit (200) to the two electric vehicles (300, 400) is a prerequisite for carrying out the method for controlling the energy transfer between the two electric vehicles (300, 400) via the charging cable (100). [12] Control unit (200) for controlling energy transfer via a charging cable (100) between two electric vehicles (300, 400), wherein the control unit (200) comprises a first processor (234), a first memory (230) with first program instructions (236) and one or more first communication interfaces (208, 211, 212), wherein the charging cable (100) comprises a control unit (105) with a second processor (122) and a second memory (120) with second program instructions (124), wherein the charging cable (100) further comprises at least a second communication interface (104), wherein the execution of the second program instructions (124) by the second processor (122) controls the charging cable (100) to communicate at least via the second communication interface (104), wherein the control unit (200) is configured to control the energy transfer between the two electric vehicles (300, 400) via the charging cable (100) upon execution of the first program instructions (236) by the first processor (234), which includes: Establishment of an initial communication link between the control unit (200) and the control unit (105) of the charging cable (100), The control unit (200) receives one or more charging parameters from both electric vehicles (300, 400), wherein the first charging parameters of the received charging parameters identify the first of the two electric vehicles (300) as an electric vehicle to receive energy and specify a first maximum current when receiving energy, and wherein the second charging parameters of the received charging parameters identify the second of the two electric vehicles (400) as an electric vehicle supplying energy and specify a second maximum current when supplying energy. wherein the control unit (200) further establishes a second wireless communication link to the first electric vehicle (300), wherein the control unit (200) receives the first charging parameters from the first electric vehicle (300) via the second communication link, wherein the control unit (200) further establishes a third wireless communication link to the second electric vehicle (400), wherein the control unit (200) receives the second charging parameters from the second electric vehicle (400) via the third communication link, Determining a transmission current for the energy transfer from the second to the first electric vehicle (300, 400) using the first and second maximum currents by the control unit (200), which is passed on to the electric vehicles involved so that their charging controllers can carry out the energy transfer accordingly, Sending one or more control commands from the control unit (200) to the control unit (105) of the charging cable (100), wherein the control commands are configured to control, upon execution by the second processor, the energy transfer between the two electric vehicles (300, 400), wherein the control commands include a specification of the transmission current to be used for the energy transfer from the second to the first electric vehicle (300, 400) via the charging cable (100). [13] Control unit (200) according to claim 12, wherein the control unit (200) is a mobile terminal (209). [14] System (600) comprising a control unit (200) according to claim 12 and the charging cable (100), which includes the control unit (105) with the second processor (122) and the second memory (120) with the second program instructions (124) and the second communication interface (104), wherein the execution of the second program instructions (124) by the second processor (122) controls the charging cable (100) at least to communication via the second communication interface (104). [15] System (600) according to claim 14, wherein the control unit (200) is a mobile terminal (209).

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