CORD SET FOR V2V, V2L, OR G2V CHARGING OR POWER SUPPLY

A cord set comprises: electric-vehicle supply equipment (EVSE) comprising circuitry, the EVSE having a receptacle; a first charging gun coupled to an end of a first cord, wherein a first connector is coupled to an opposite end of the first cord, and wherein the first connector is configured to be coupled with the receptacle for vehicle-to-vehicle charging; a second charging gun coupled to an end of a second cord, wherein an opposite end of the second cord is coupled to the EVSE; and a grid cord, wherein a second connector is coupled to an end of the grid cord, and wherein the second connector is configured to be coupled with the receptacle for grid-to-vehicle charging.

TECHNICAL FIELD

This document relates to a cord set for V2V, V2L, or G2V charging or power supply.

BACKGROUND

In recent years, electric vehicle (EV) technology has continued to develop, and an increasing number of people are choosing to have an EV as a personal vehicle. An EV has an onboard battery pack or other energy storage. In the past, EV batteries have been utilized as the source of energy for the EV itself (e.g., for its powertrain and electrical components).

SUMMARY

In a first aspect, a cord set comprises: electric-vehicle supply equipment (EVSE) comprising circuitry, the EVSE having a receptacle; a first charging gun coupled to an end of a first cord, wherein a first connector is coupled to an opposite end of the first cord, and wherein the first connector is configured to be coupled with the receptacle for vehicle-to-vehicle charging; a second charging gun coupled to an end of a second cord, wherein an opposite end of the second cord is coupled to the EVSE; and a grid cord, wherein a second connector is coupled to an end of the grid cord, and wherein the second connector is configured to be coupled with the receptacle for grid-to-vehicle charging.

Implementations can include any or all of the following features. The EVSE further comprises a voltage divider, wherein the first charging gun has a proximity pin, and wherein coupling of the first connector with the receptacle causes the voltage divider to be coupled to the proximity pin through the first cord. The voltage divider includes at least a resistor, wherein coupling the resistor to the proximity pin through the first cord lowers a voltage at the proximity pin. The EVSE detects whether the first or second connector is coupled with the receptacle. Each of the first and second charging guns is a J1772 charging gun. The cord set is configured so that vehicle-to-vehicle charging with the first connector coupled with the receptacle involves the first charging gun being coupled to a donor electric vehicle, and the second charging gun being coupled to an acceptor electric vehicle. The cord set is configured so that grid-to-vehicle charging with the second connector coupled with the receptacle involves the second charging gun being coupled to an electric vehicle to be charged.

In a second aspect, a method comprises: providing, by a first electric vehicle (EV), a first voltage at a proximity pin, wherein a first cord couples the proximity pin to EV supply equipment (EVSE); detecting, by the first EV, a second voltage at the proximity pin; based on the second voltage having a first level, initiating, by the first EV, grid-to-vehicle charging of the first EV; and based on the second voltage having a second level different from the first level, initiating, by the first EV, vehicle-to-vehicle charging with the first EV as a donor vehicle and a second EV as an acceptor vehicle.

Implementations can include any or all of the following features. The method further comprises prompting, in response to the second voltage having the second level, a user for input whether to initiate the vehicle-to-vehicle charging. The method further comprises detecting, by the first EV and for the grid-to-vehicle charging, a third voltage on a pilot pin coupled to the EVSE by the cord, wherein the third voltage represents a level of current available for the grid-to-vehicle charging. The method further comprises providing, by the first EV and for the vehicle-to-vehicle charging, a third voltage on a pilot pin coupled to the EVSE by the cord, wherein the third voltage represents a level of current available for the vehicle-to-vehicle charging. The method further comprises terminating, by the first EV, the vehicle-to-vehicle charging. The first EV is associated with an application, the method further comprising receiving, by the first EV, a stop command generated by the application, wherein the first EV terminates the vehicle-to-vehicle charging in response to receiving the stop command. The first EV has a touchscreen, the method further comprising receiving, by the first EV, a stop command entered by a user using the touchscreen, wherein the first EV terminates the vehicle-to-vehicle charging in response to receiving the stop command. A charging gun is coupled to an end of the cord, wherein the charging gun is coupled to the first EV for the vehicle-to-vehicle charging, wherein the charging gun has a button, and wherein the first EV terminates the vehicle-to-vehicle charging in response to the button being pressed. The method further comprises receiving, by the first EV, a signal from the EVSE, wherein the first EV terminates the vehicle-to-vehicle charging in response to the signal. A charging gun is coupled to the second EV for the vehicle-to-vehicle charging, wherein the charging gun has a button, and wherein sending of the signal was triggered by pressing of the button. The method further comprises detecting, by the first EV, a fault in the vehicle-to-vehicle charging, and changing a state of the first vehicle in response to the fault.

In a third aspect, a cord set comprises: a power strip comprising circuitry, the power strip having a receptacle; a first charging gun coupled to an end of a cord, wherein a first connector is coupled to an opposite end of the cord, and wherein the first connector is configured to be coupled with the receptacle for vehicle-to-load power supply; and a grid cord, wherein a second connector is coupled to an end of the grid cord, and wherein the second connector is configured to be coupled with the receptacle for grid-to-load power supply.

Implementations can include any or all of the following features. The power strip further comprises a voltage divider, wherein the first charging gun has a proximity pin, and wherein coupling of the first connector with the receptacle causes the voltage divider to be coupled to the proximity pin through the first cord. The voltage divider includes at least a resistor, wherein coupling the resistor to the proximity pin through the first cord lowers a voltage at the proximity pin.

DETAILED DESCRIPTION

This document describes examples of systems and techniques for facilitating use of the energy storage of an electric vehicle (EV) to provide power to one or more other electric apparatuses. For example, the other electric apparatus can be another EV that uses the received electricity to charge its own energy storage. As another example, the other apparatus can be an electric device that receives its power from the EV by being plugged into a power strip coupled to the EV. Cord sets described herein can facilitate communication schemes that enable charging of an EV with power from a grid, as well as conveying electricity from the EV to other equipment. This can enable use of the EV's battery pack as a mobile energy storage.

Examples described herein refer to a vehicle. A vehicle is a machine that transports passengers or cargo, or both. A vehicle can have one or more motors using at least one type of fuel or other energy source (e.g., electricity). Examples of vehicles include, but are not limited to, cars, trucks, and buses. The number of wheels can differ between types of vehicles, and one or more (e.g., all) of the wheels can be used for propulsion of the vehicle. The vehicle can include a passenger compartment accommodating one or more persons. An EV can be powered exclusively by electricity, or can use one or more other energy sources in addition to electricity, to name just a few examples. As used herein, an EV includes an onboard energy storage, sometimes referred to as a battery pack, to power one or more electric motors. Two or more EVs can have different types of energy storages and/or different sizes thereof.

Examples described herein refer to vehicle-to-vehicle (V2V) charging. As used herein, V2V is performed with at least two EVs, wherein a first EV serves as a donor EV for energy and one or more second EVs serve as acceptor EVs for energy. The V2V charging involves discharging the donor EV and charging the second EV(s). Charging an energy storage involves supplying energy into the storage and increasing its state of charge. Discharging an energy storage involves removing energy from the storage and decreasing its state of charge. As such, in V2V charging there is both charging and discharging involved, of separate EVs. Moreover, an electrical connector that is coupled to an EV is sometimes referred to as a charging gun. In V2V charging, respective charging guns are coupled to each of the EVs. That is, charging guns are used for both the donor EV and the acceptor EV(s). When an EV is instead being charged with electricity from a grid, this can be referred to as grid-to-vehicle (G2V) charging.

Examples described herein refer to vehicle-to-load (V2L) power supply. As used herein, in V2L power supply an EV serves as a donor EV for energy for one or more loads. The V2L power supply involves discharging of the EV and consumption of electrical energy by the load(s). When the load is instead supplied with electricity from a grid, this can be referred to as grid-to-load (G2L) power supply.

Examples described herein refer to a power grid, or a grid for short. As used herein, a grid that supplies power includes any of multiple types of networks for delivering electricity from a producer to one or more consumers. A grid can be owned and/or operated by any of multiple types of actors, including, but not limited to, a public entity (e.g., a municipality, city, state, or country) that may act through one or more utility companies, or a private entity (e.g., a corporation, another private enterprise, or an individual). A grid can deliver electricity to a building at any of multiple levels of power.

Examples described herein describes certain components of an electric circuit as being coupled to each other. As used herein, being coupled means to be electrically coupled, unless otherwise stated.

FIG.1shows an example of a cord set100that can perform V2V or G2V charging. The cord set100can be used with one or more other examples described elsewhere herein. The cord set100is here shown as being associated with a donor EV102and acceptor EVs104A-104B. Each of the donor EV102and the acceptor EVs104A-104B can be any of multiple types of EV having an onboard energy storage (e.g., battery pack) that can be charged from an external power source. The donor EV102and the acceptor EV104A are here shown as being the same model of EV, whereas the acceptor EV104B is a different EV model (e.g., from the same or a different manufacturer) from the donor EV102and the acceptor EV104A. The vehicle types that are being shown (e.g., a sedan vehicle, or other type of passenger vehicle) are used for illustrative purposes only.

The cord set100includes electric-vehicle supply equipment (EVSE)106. The EVSE106includes circuitry for communicating with the donor EV102and the acceptor EVs104A-104B. The EVSE106can be configured for power flow in a left-to-right direction in the present illustration. The EVSE106has a receptacle108for electric connection. Any type of electrical connector that is compatible with the intended levels of current and voltage, and that supports adequate communication ability, can be used. In some implementations, the receptacle108is configured for being used with AC mains electricity.

The cord set100includes a charging gun110A coupled to an end of a cord112A. A connector114A is coupled to an opposite end of the cord112A from the charging gun110A. The connector114A is configured to be coupled with the receptacle108for V2V charging. For example, in such V2V charging, the EV102can be the donor vehicle.

The cord set100includes a charging gun110B coupled to an end of a cord112B. An opposite end of the cord112B from the charging gun110B can be coupled to the EVSE106. For example, the opposite end can be permanently attached to the EVSE106, or the opposite end can have a connector (e.g., a plug and corresponding receptacle) that facilitates removable coupling with the EVSE106.

The charging guns110A-110B can be any type(s) of charging gun compatible with one or more of the EVs. For example, multiple power pins and one or more control pins can be included to facilitate communications and transfer of electricity through the associated cord.

The cord set100includes a grid cord116. A connector114B is coupled to an end of the grid cord116. The connector114B is configured to be coupled with the receptacle108for G2V charging. For example, in such G2V charging, any of the EVs102or104A-104B can be the EV being charged. A grid plug118is coupled to an opposite end of the grid cord116from the connector114B.

As mentioned, when the connector114A is coupled to the receptacle108the cord set100can perform V2V charging, and when the connector114B is coupled to the receptacle108the cord set100can perform G2V charging. The cord set100can communicate to one or more of the EVs102or104A-104B whether it is the cord112A, or the grid cord116, that is coupled to the receptacle108. Namely, the charging guns110A-110B may be substantially identical to each other, and the EV that has either of them plugged in needs to know whether it will act as a donor EV or as an acceptor EV.

The EVSE106can include a voltage divider120, here shown in an enlarged inset. The voltage divider120can be coupled to the circuitry of the EVSE106. When the connectors114A-114B are coupled to the receptacle108, the voltage divider120can be coupled to the circuitry so as to be included in a proximity-pin line. The voltage divider120can include at least one resistor122. The coupling of the voltage divider120to the circuitry of the EVSE106can correspond to either including the resistor122in the proximity-pin line (for V2V charging), or not including the resistor122in the proximity-pin line (for G2V charging). Both the connectors114A and114B will couple to the voltage divider120. The connectors114A and114B have different internal designs, and hence, when coupled to the voltage divider120, they will generate different detectable voltages. The EVSE106and the vehicle can detect the corresponding voltages for the connectors114A and114B to decide the states.

Any of the charging guns110A-110B can have one or more actuatable features. In some implementations, the charging gun110A has a button124A, and the charging gun110B has a button124B. For example, each of the buttons124A-124B can control an electric relay or other switch (sometimes referred to as a latch).

FIG.2shows an example of a cord set200that can perform V2L or G2L power supply. The cord set200can be used with one or more other examples described elsewhere herein. The cord set200is here shown as being associated with the donor EV102.

The cord set200includes a power strip202. The power strip202includes circuitry for communicating with the donor EV102. The power strip202can be configured for power flow in a left-to-right direction in the present illustration. The power strip202has the receptacle108for electric connection.

The cord set200includes the charging gun110A coupled to the end of the cord112A, and the connector114A is coupled to the opposite end of the cord112A. For example, in V2L power supply, the EV102can be the donor vehicle. The power strip202includes one or more receptacles204. An electric component can be plugged into the receptacle204to receive electricity through the power strip202.

The cord set200includes the grid cord116, with the connector114B coupled to the end thereof, and the grid plug118is coupled to an opposite end of the grid cord116. For example, in G2L power supply, the electric component plugged into the receptacle204can be provided with electricity from the grid.

As mentioned, when the connector114A is coupled to the receptacle108the cord set200can perform V2L power supply, and when the connector114B is coupled to the receptacle108the cord set200can perform G2L power supply. The cord set200can communicate to the EV102that the cord112A is coupled to the receptacle108. Namely, the EV102that has the charging gun110A plugged in needs to know whether it will act as a donor EV or be charged with energy. The power strip202can include the voltage divider120(FIG.1) coupled to the circuitry of the power strip202. The voltage divider120can include at least the resistor122. The coupling of the voltage divider120to the circuitry of the power strip202can correspond to either including the resistor122in the proximity-pin line (for V2L power supply).

FIG.3shows an example of communication flows relating to the EVs102and104A. The communication flows can be used with one or more other examples described elsewhere herein. The EVs102and104A are used for illustrative purposes only. For example, in a different implementation the communication flows can occur with regard to EVs that are not of the same type as each other.

The communication flows include a V2V plug detection300. In some implementations, the EV102provides a voltage on a proximity pin at its charge port, which proximity pin is coupled to the EVSE106by the cord. The EV102can detect the resulting voltage at the proximity pin. For at least one specific detected voltage, the detection triggers the EV102to initiate G2V charging. This can involve the EV102receiving a signal302(here, an input signal) on a pilot pin regarding the G2V charging. For example, the EVSE106can inform the EV102what current level(s) the EVSE106can provide.

For at least one other specific detected voltage, the detection triggers the EV102to initiate V2V charging. Contrary to the previous example where an input signal was received at the pilot pin, V2V can instead involve the signal302on the pilot pin being an output signal from the EV102regarding the V2V charging. For example, the EV102can inform the EVSE106what current level(s) the EV102can provide. Circuitry304of the EVSE106(e.g., a pilot detector) can be invoked with the signal302in both G2V and V2V charging.

The EVSE106includes a controller (sometimes referred to as an MCU)306. The controller306can handle communications to and from the EVSE106in G2V and V2V charging. The EVSE106includes circuitry308(e.g., a pilot generator) coupled to the controller306. In some implementations, the circuitry308can generate a signal310to the EV104A. For example, the signal310can be referred to as an acceptor pilot signal and can be detected at a pilot pin of the EV104A. One or both of the circuitries304and308can handle communication based on pulse width modulation (PWM) signals. Examples of signaling are provided below.

Examples described herein regarding communication flows during G2V and V2V charging also apply, with modifications, to scenarios that involve V2L power supply or G2L power supply. For example, the power strip202(FIG.2) can include some or all of the described circuitry of the EVSE106.

FIG.4shows an example of pin mapping. Any or all of the pins described can be used with one or more other examples described elsewhere herein. These examples involve a donor vehicle interface400and an EVSE interface402. The donor vehicle interface400can include power pins (here labeled L1 and L2/N, respectively) for conveying electricity to the EV during charging, or from the EV when the EV serves as a donor vehicle. The donor vehicle interface400includes a proximity pin404A, a pilot pin406A, and an equipment ground pin408. The EVSE interface402includes some corresponding pins, such as a proximity pin404B and a pilot pin406B.

A voltage level410can be generated and be forwarded in either direction between the proximity pins404A-404B. The voltage level410is generated when either of the the connectors114A and114B (FIG.1) is plugged in. For example, the voltage level410can be based on detection of a negative temperature coefficient resistor at the EVSE. As another example, the voltage level410can be based on detection of whether V2V charging should be initiated.

A signal412can be generated and be forwarded in either direction between the pilot pins406A-406B. For example, the signal412can involve detection of a grid plug. As another example, the signal412can involve transmitting a control pilot signal from a donor EV.

FIG.5shows an example of detectable states500for V2V, V2L, or G2V charging or power supply. Any or all of the detectable states500can be used with one or more other examples described elsewhere herein. The different states are indicated against a horizontal axis labeled proximity state (e.g., the states can be detected using a pin referred to as a proximity pin). The states are characterized as having voltages in different ranges, such voltages indicated against a vertical axis labeled proximity voltage range. Seven states are shown and are here referred to as states500-1through500-7, respectively. States500-1and500-2can be associated with V2V charging. States500-3and500-4can be associated with V2L power supply. States500-5,500-6, and500-7can be associated with G2V charging.

The state500-1can be associated with pressing of a latch on the charging gun that is coupled to the donor EV. For example, the button124A (FIG.1) of the charging gun110A can be pressed to generate the voltage corresponding to the state500-1. The state500-2can correspond to the latch being released. In some implementations, the state500-1is a quick state and the state500-2is the steady state when the button is released. The states500-1and500-2can have a lower voltage than other states of the detectable states500. As such, the invocation of V2V charging, which can be done by coupling the voltage divider (e.g., the resistor122inFIG.1) to the proximity pin through the cord, can involve lowering a voltage at the proximity pin.

FIG.6shows an example of a pulse width modulation (PWM) diagram600relating to V2V charging. The PWM diagram600can be used with one or more other examples described elsewhere herein. The PWM diagram600includes a diagram602relating to signals on the pilot pin of a donor EV, and a diagram604relating to signals on the pilot pin of an acceptor EV. Different states are indicated against a horizontal axis. In the various states, the PWM signal can have voltages in different ranges, such voltages indicated against respective vertical axes for the diagrams602and604. In the following, the various states are discussed in order from left to right in the PWM diagram600.

In state D-E for the donor, no PWM is generated. In the corresponding state A for the acceptor, a 12V signal can be generated. This state can correspond to a charging gun not being plugged into the acceptor EV, wherein no connection is made. For example, AC discharge of the donor EV can be enabled, and the EVSE can be powered on.

In state D-B for the donor, a 9V signal can be generated. In the corresponding state B1 for the acceptor, a 9V signal can be generated. Once the charging gun in plugged into the acceptor EV, the voltage can be automatically pulled down to 9V.

In state D-C for the donor, a 6-9V PWM signal is generated. In the corresponding state B2 for the acceptor, a 9V PWM signal can be generated. The EVSE can detect a state and generate a 9V PWM signal.

In state D-C for the donor, the donor can maintain the 6-9V PWM signal. In the corresponding state C for the acceptor, a 6V PWM signal can be generated. The acceptor EV can detect the 9V PWM, and understand a duty ratio of the PWM signal about current limitation. The acceptor EV can therefore pull down the PWM signal to a 6V PWM. The acceptor EV can receive the same level of current that the donor EV is capable of discharging, or a lesser level if the EVSE cannot deliver the full level. State C for the acceptor is where energy is transferred from the donor EV to the acceptor EV. The duty ratio can change during this process. Both the donor and the acceptor can change the duty ratio. For example, the donor regulates its production of current based on state of charge. The EVSE can derate itself based on its temperature.

In state D-C for the donor, the 6-9V PWM signal can be generated. In the corresponding state B2 for the acceptor, a 9V PWM signal can be generated. This can be the reverse of the initialization process. The acceptor EV can stop the process by changing the PWM signal from 6V to 9V.

In state D-B for the donor, a 9V signal can be generated. In the corresponding state B1 for the acceptor, a 9V signal can be generated. The EVSE can detect the stopping by the acceptor EV and stop the process.

In state D-E for the donor, no signal is generated. In the corresponding state A for the acceptor, a 12V signal can be generated. This state can correspond to a charging gun not being plugged into the acceptor EV, wherein no connection is made.

FIG.7shows an example of a state diagram700regarding a starting sequence for V2V charging. The state diagram700can be used with one or more other examples described elsewhere herein. Operations702,706, and710correspond to actions taken by a user. Operations704and712correspond to actions taken and/or states entered into by, a donor EV. Operation708corresponds to an action taken and/or state entered into by, an acceptor EV. Operation714corresponds to actions taken and/or states entered into by, an EVSE.

In operation702, a user can connect a V2V plug to a donor EV.

In operation704A, an onboard charger (OBC) of the donor vehicle can detect a V2V session by way of a proximity pin (PP). In operation704B, the donor EV can present a message to a user (e.g., on a touchscreen device) that V2V discharging is available to be initiated. For example, the message can prompt the user for input and indicate that the onboard charger waits for the user to activate V2V discharging.

In operation706, a user can connect a charging gun to an acceptor EV.

In operation708, the acceptor EV can detect a state (e.g., state D-E for the acceptor pilot inFIG.6). The detection can be made based on a control pilot (CP; e.g., the donor EV's PWM signal) on the pilot pin and a proximity pin signal.

In operation710, a user can activate V2V charging using an application or by way of a touchscreen input. For example, an application associated with the donor EV can run on a mobile electronic device controlled by the user. The application can activate V2V charging.

In operation712A, the onboard charger of the donor EV can engage in a handshaking procedure with a vehicle control unit (VCU) and/or a battery management unit (BMU). In operation712B, the onboard charger can generate AC power from the donor EV's energy storage, and can generate a PWM signal on the control pilot.

In operation714A, the EVSE can perform a self-check procedure. In operation714B, the EVSE can perform a charging gun handshake (e.g., according to the J1772 standard from SAE International) with the acceptor EV. In operation714C, the EVSE can close its relay on the power line(s) and V2V charging can begin.

FIGS.8-9show examples of state diagrams regarding stopping sequences for V2V charging.FIG.8shows an example of a state diagram800regarding stopping (e.g., terminating) V2V charging using an application, or a touchscreen, or a V2V plug button for the donor EV.FIG.9shows an example of a state diagram900regarding stopping (e.g., terminating) V2V charging using a charging gun button for the acceptor EV. The state diagrams800and/or900can be used with one or more other examples described elsewhere herein.

Operations802and814correspond to actions taken by a user. Operations804and808correspond to actions taken and/or states entered into by, a donor EV. Operation812corresponds to an action taken and/or state entered into by, an acceptor EV. Operations806and810correspond to actions taken and/or states entered into by, an EVSE.

Beginning with the state diagram800, at an operation802, in a first case, a user can use an application or a touchscreen input to deactivate V2V charging. This can be done by making an input that generates a stop command. In a second case, the user can press a button on the V2V-plug (e.g., the charging gun plugged into the donor EV).

In operation804A, the onboard charger of the donor EV can engage in a handshaking procedure with a VCU and/or a BMU. In operation804B, the onboard charger can stop the PWM signal on the control pin.

In operation806A, the EVSE can perform a handshake (e.g., according to the J1772 standard from SAE International) with the acceptor EV to stop charging. In operation806B, the EVSE can open its relay on the power line(s). In operation806C, the EVSE can engage in a handshake procedure with the donor EV to stop the discharging from the donor.

In operation808, the onboard charger of the donor EV can stop its AC power output.

In operation810, the EVSE can detect that it has lost power.

In operation812, the acceptor EV can detect a state (e.g., state D-E for the donor pilot inFIG.6). The detection can be made based on a control pilot (CP; e.g., the donor EV's PWM signal) on the pilot pin and a proximity pin signal.

In operation814, the user can unplug the V2V-plug from the donor EV and the charging gun from the acceptor EV.

Turning now to the state diagram900, operations902and910correspond to actions taken by a user. Operation904corresponds to an action taken and/or state entered into by, an acceptor EV. Operation906corresponds to actions taken and/or states entered into by, an EVSE. Operation908corresponds to actions taken and/or states entered into by, a donor EV.

In operation902, the user can press the button on the charging gun coupled to the acceptor EV.

In operation904, the acceptor EV can detect a change on a proximity pin as a result of the button press, and can execute a stop sequence in response.

In operation906A, the EVSE can open its relay on the power line(s). In operation906B, the EVSE can engage in a handshaking procedure with the donor EV to stop its discharging.

In operation908A, the onboard charger of the donor EV can stop its AC power output. In operation908B, the onboard charger can engage in a handshaking procedure with a VCU and/or a BMU to stop the V2V charging.

In operation910, the user can unplug the V2V plug from the donor EV, and unplug the charging gun from the acceptor EV.

FIGS.10-11show examples of state diagrams regarding detecting a fault for V2V charging.FIG.10shows an example of a state diagram1000regarding detection of a fault during V2V charging when a V2V plug is disconnected from the EVSE box.FIG.11shows an example of a state diagram1100regarding detection of a fault during V2V charging when the EVSE detects a fault in itself. The state diagrams1000and/or1100can be used with one or more other examples described elsewhere herein.

Operation1002corresponds to an ongoing process. Operation1004corresponds to actions taken and/or states entered into by, a donor EV. Operation1006corresponds to an action taken and/or state entered into by, an EVSE. Operation1008corresponds to an action taken and/or state entered into by, an acceptor EV.

In operation1002, a V2V charging session is in progress.

In operation1004A, an onboard charger of the donor EV detects a stop of the V2V session by a signal at a proximity pin.

At operation1004B, the donor EV stops its AC power output.

At operation1004C, the onboard charger of the donor EV can engage in a handshaking procedure with a VCU and/or a BMU to stop the discharging.

At operation1006, the EVSE can detect that it has lost power, and can open its relay at the power line(s).

At operation1008, the acceptor EV can change from state C (e.g., where a 6V PWM signal is generated, seeFIG.6) to state E. For example, in state E the proximity signal can be engaged, but the control pilot is lost. At operation1008, since the V2V cable is disconnected from the EVSE, the EVSE power supply is lost, and hence the control pilot is lost. However, the proximity pin may be available, and the vehicle may see a valid proximity pin signal, as long as the charging gun is plugged into the vehicle.

Turning now to the state diagram1100, operation1102corresponds to an ongoing process. Operation1104corresponds to actions taken and/or states entered into by, an EVSE. Operation1106corresponds to an action taken and/or state entered into by, a donor EV. Operation1108corresponds to an action taken and/or state entered into by, an acceptor EV.

In operation1102, a V2V charging session is in progress.

In operation1104A, an EVSE can change its state from state C (e.g., where a 6V PWM signal is generated, seeFIG.6) to state E. Regarding state E, see description of operation1008above.

At operation1104B, the EVSE can open its relay at the power line(s).

At operation1104C, the EVSE can change the voltage polarity for the signal at the control pin of the donor EV.

At operation1106A, the donor EV can stop its AC power output.

At operation1106B, the onboard charger of the donor EV can engage in a handshaking procedure with a VCU and/or a BMU to stop the V2V session.

At operation1108, the acceptor EV can exit its charging state.

The terms “substantially” and “about” used throughout this Specification are used to describe and account for small fluctuations, such as due to variations in processing. For example, they can refer to less than or equal to ±5%, such as less than or equal to ±2%, such as less than or equal to ±1%, such as less than or equal to ±0.5%, such as less than or equal to ±0.2%, such as less than or equal to ±0.1%, such as less than or equal to ±0.05%. Also, when used herein, an indefinite article such as “a” or “an” means “at least one.”

In addition, the logic flows depicted in the figures do not require the particular order shown, or sequential order, to achieve desirable results. In addition, other processes may be provided, or processes may be eliminated, from the described flows, and other components may be added to, or removed from, the described systems. Accordingly, other implementations are within the scope of the following claims.