Traction battery charging

Abstract

The present disclosure provides "traction battery charging". In response to a request to DC fast charge a traction battery at a charging station providing a plurality of DC fast charge rates, a controller generates, for only each of the rates corresponding to an aging parameter of the traction battery that is less than a threshold, an output indicative of a cost of charging the traction battery at the rate, each of the plurality of DC fast charge rates has a cost per unit time that increases as the rate increases.

Description

Technical Field

[0001] The present disclosure relates to strategies for charging electric vehicles. Background Art

[0002] An electric vehicle is provided with one or more traction batteries for propulsion. The traction batteries can be recharged by a charger. Summary of the invention

[0003] A vehicle includes a traction battery and a controller. The controller: in response to a request for DC fast charging of the traction battery at a charging station that provides a plurality of DC fast charging rates, generates an output for only each of the rates that corresponds to an aging parameter of the traction battery that is less than a threshold, the output indicating a cost of charging the traction battery at the rate, each of the plurality of DC fast charging rates having a cost per unit time that increases as the rate increases; and charges the traction battery at a selected one of the rates.

[0004] A method includes, upon receiving a request for DC fast charging of a traction battery at a charging station that provides a plurality of DC fast charging rates, charging the traction battery at one of the rates automatically selected based on a total cost such that the total cost is less than a threshold cost, the total cost including a portion representing a cost of electricity for the charging, a cost of time for a user of the charging, and a cost of aging of the traction battery of the charging, each of the plurality of DC fast charging rates having a cost per unit of time that increases as the rate increases.

[0005] A vehicle control system includes a controller that charges a traction battery at one of a plurality of DC fast charge rates, the one of the plurality of DC fast charge rates being selected such that the one rate corresponds to an aging parameter of the traction battery that is less than a threshold, the aging parameter being based on a duration of the charging. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 is a diagram of an electrified vehicle showing a powertrain and energy storage components including an electric machine.

[0007] Figure 2 It is a block topology for vehicle charging system.

[0008] Figure 3 is a flow chart of the process of charging an electric vehicle. DETAILED DESCRIPTION

[0009] Embodiments are described herein. However, it should be understood that the disclosed embodiments are merely examples and that other embodiments may take various and alternative forms. The drawings are not necessarily drawn to scale. Some features may be enlarged or minimized to show details of particular components. Therefore, the specific structural details and functional details disclosed herein should not be interpreted as limiting, but merely as a representative basis for teaching those skilled in the art.

[0010] The various features shown and described with reference to any one of the accompanying drawings may be combined with features shown in one or more other drawings to produce embodiments not explicitly shown or described. The combinations of features shown provide representative embodiments for typical applications. However, for specific applications or implementations, various combinations and modifications of features consistent with the teachings of the present disclosure may be desired.

[0011] The present disclosure proposes, among other things, a system and method for charging an electric vehicle. Conventionally, the total price of charging an electric vehicle can be determined by the total amount of electrical energy received by the vehicle. With the introduction of high-power DC chargers, utility companies can set pricing rates based on the maximum charging power that varies over time. For example, a 150kW DC fast charging power may correspond to $0.99 / min, while a 75kW DC fast charging power may correspond to only $0.25 / min. In a variable power charging process, the charger can adjust the charging power based on real-time feedback from the vehicle battery. The charging process may start with a high charging power when the battery state of charge (SOC) is low, and gradually reduce the charging power as the SOC increases. However, the pricing rate corresponding to the maximum charging power may be applied throughout the charging process. Continuing with the current example, if the charging process starts with a charging power of 150kW, the pricing of the current charging process will be set to $0.99 / min throughout the process, even if the charging power is subsequently reduced to 75kW. In other words, the pricing rate of the charging process is determined by the highest charging power, despite the fact that the highest charging power is only utilized at the beginning of the process. The present disclosure proposes a system for charging a vehicle while allowing the user to save.

[0012] Figure 1An electrified vehicle 112, which may be referred to as a plug-in hybrid electric vehicle (PHEV), a battery electric vehicle (BEV), and / or a full hybrid electric vehicle (FHEV), is depicted. The plug-in hybrid electric vehicle 112 may include one or more motors 114 mechanically coupled to a hybrid transmission 116. The motor 114 may be capable of operating as a motor or a generator. In addition, the hybrid transmission 116 is mechanically coupled to an engine 118. The hybrid transmission 116 is also mechanically coupled to a drive shaft 120, which is mechanically coupled to wheels 122. The motor 114 may provide propulsion and braking capabilities when the engine 118 is turned on or off. The motor 114 may also act as a generator and may provide fuel economy benefits by recovering energy that would normally be lost as heat in a friction braking system. The motor 114 may also reduce vehicle emissions by allowing the engine 118 to operate at a more efficient speed and allowing the hybrid electric vehicle 112 to operate in an electric mode when the engine 118 is turned off under certain conditions. The electrified vehicle 112 may also be a BEV. In a BEV configuration, the engine 118 may not be present.

[0013] The traction battery or battery pack 124 stores energy that can be used by the motor 114. The vehicle battery pack 124 can provide a high voltage direct current (DC) output. The traction battery 124 can be electrically coupled to one or more power electronics modules 126 (such as a traction inverter). The power electronics module 126 is also electrically coupled to the motor 114 and provides the ability to transfer energy bidirectionally between the traction battery 124 and the motor 114. For example, the traction battery 124 can provide a DC voltage, and the motor 114 can operate using three-phase alternating current (AC) to function. The power electronics module 126 can convert the DC voltage into a three-phase AC current to operate the motor 114. In the regenerative mode, the power electronics module 126 can convert the three-phase AC current from the motor 114 acting as a generator into a DC voltage compatible with the traction battery 124.

[0014] The vehicle 112 may include a variable voltage converter (VVC) (not shown) electrically coupled between the traction battery 124 and the power electronics module 126. The VVC may be a DC / DC boost converter configured to increase or step up the voltage provided by the traction battery 124. By increasing the voltage, current requirements may be reduced, resulting in a reduction in wiring size of the power electronics module 126 and the motor 114. Additionally, the motor 114 may be operated with better efficiency and lower losses.

[0015] In addition to providing energy for propulsion, the traction battery 124 can also provide energy for other vehicle electrical systems. The vehicle 112 can include a DC / DC converter module 128 that converts the high voltage DC output of the traction battery 124 to a low voltage DC supply that is compatible with low voltage vehicle loads 129. The output of the DC / DC converter module 128 can be electrically coupled to an auxiliary battery 130 (e.g., a 12V battery) for charging the auxiliary battery 130. The low voltage system can be electrically coupled to the auxiliary battery 130.

[0016] The electrified vehicle 112 may be configured to recharge the traction battery 124 from an external power source 136. The external power source 136 may be a connection to an electrical outlet. The external power source 136 may be electrically coupled to a charger or electric vehicle supply equipment (EVSE) 138. The external power source 136 may be a distribution network or grid provided by an electric utility company. The EVSE 138 may provide circuitry and controls to manage energy transfer between the power source 136 and the vehicle 112. The external power source 136 may provide DC or AC power to the EVSE 138. The EVSE 138 may have a charging connector 140 for plugging into a charging port 142 of the vehicle 112. The charging port 142 may be any type of port configured to transfer power from the EVSE 138 to the vehicle 112. The charging port 142 may be electrically coupled to a charger or an onboard power conversion module 144. The power conversion module 144 may regulate the power supplied from the EVSE 138 to supply the appropriate voltage and current levels to the traction battery 124. The power conversion module 144 may interface with the EVSE 138 to coordinate power delivery to the vehicle 112. The EVSE 138 may output a DC fast charging current to charge the traction battery 124 via the power conversion module 144. The EVSE 138 may adjust the charging power by varying the current (or voltage) output. The EVSE connector 140 may have pins that match corresponding recesses of the charging port 142. Alternatively, the various components described as being electrically coupled or connected may use wireless inductive coupling to transfer power. In addition, the charging port 142 may be configured to output DC power from the traction battery 124 through the power conversion module 144. One or more contactors 146 may isolate the traction battery 124 from other components when open, and connect the traction battery 124 to other components when closed.

[0017] The electronic modules / controllers in the vehicle 112 can communicate via one or more vehicle networks (described in detail below). The vehicle network can include multiple channels for communication. The channels of the vehicle network can include discrete connections between modules and can include power signals from the auxiliary battery 130. Different signals can be transmitted through different channels of the vehicle network. For example, a video signal can be transmitted through a high-speed channel, while a control signal can be transmitted through a low-speed channel. The vehicle network can include any hardware and software components that facilitate the transmission of signals and data between modules. A computing platform 148 may be present to perform and coordinate various operations of the vehicle 112.

[0018] Figure 2 200 is a block topology of a vehicle charging system. The computing platform 148 of the vehicle 112 may include one or more processors 204 configured to execute instructions, commands, and other programs that support the processes described herein. For example, the computing platform 148 may be configured to execute instructions of a vehicle application 206 to provide features such as communication and charging control. Such instructions and other data may be maintained in a non-volatile manner using a variety of types of computer-readable storage media 208. Computer-readable media 208 (also referred to as processor-readable media or storage devices) include any non-temporary media (tangible media) that participate in providing instructions or other data that can be read by the processor 204 of the computing platform 148. Computer-executable instructions may be compiled or interpreted according to a computer program created using a variety of programming languages ​​and / or technologies, including but not limited to the following items alone or in combination: Java, C, C++, C#, Objective C, Fortran, Pascal, Java Script, Python, Perl, and SQL.

[0019] The computing platform 148 may be provided with various features that allow a vehicle occupant / user to interact with the computing platform 148. For example, the computing platform 148 may receive input from a human-machine interface (HMI) control 210 that is configured to provide occupant interaction with the vehicle 112. As an example, the computing platform 148 may interface with one or more buttons (not shown) or other HMI controls (e.g., steering wheel audio buttons, a push-to-talk button, instrument panel controls, etc.) that are configured to invoke functionality on the computing platform 148 and other components of the vehicle 112.

[0020] The computing platform 148 may also drive or otherwise communicate with one or more displays 212 configured to provide visual output to vehicle occupants via a video controller 214. In some cases, the display 212 may be a touch screen that is also configured to receive user touch input via the video controller 214, while in other cases, the display 212 may be just a display without touch input capabilities. The computing platform 148 may also drive or otherwise communicate with one or more speakers 218 configured to provide audio output to vehicle occupants via an audio controller 220.

[0021] The computing platform 148 may be configured to communicate with a mobile device 222 of a vehicle user via a wireless connection 224. The mobile device 222 may be any of various types of portable computing devices capable of communicating with the computing platform 148, such as a cellular phone, a tablet computer, a smart watch, a laptop computer, a portable music player, a key fob, or other device. In many examples, the computing platform 148 may include a wireless transceiver 226 that communicates with a Wi-Fi controller 228, a near field controller (NFC) 229, a Bluetooth controller 230, and other controllers such as a Zigbee transceiver, an IrDA transceiver, an RFID transceiver (not shown), and is configured to communicate with a compatible wireless transceiver 232 of the mobile device 222. The computing platform 148 may also be provided with location services via a global navigation satellite system (GNSS) controller 234 that is configured to determine the location of the vehicle 112 and plan a navigation route. For example, as an example, the GNSS controller 234 may be configured to support a global positioning system (GPS). Navigation software may be stored in non-volatile storage 208 as part of vehicle applications 206 . Map data used for route planning may also be stored in non-volatile storage 208 as part of vehicle data 236 .

[0022] The mobile device 222 may be provided with a processor 238 configured to execute instructions, commands, and other programs that support processes such as calls, wireless communications, multimedia processing, and digital authentication. The wireless transceiver 232 of the mobile device 222 may communicate with a Wi-Fi controller 240, a Bluetooth controller 242, an NFC controller 244, and other controllers, and may be configured to communicate with a compatible wireless transceiver 226 of the computing platform 148. The mobile device 222 may be provided with a non-volatile storage device 246 configured to store various software and data. For example, the non-volatile storage device 246 may store mobile applications 248 and mobile data 250 to enable various features of the mobile device 222.

[0023] The computing platform 148 may also be configured to communicate with the charging controller 252 via one or more vehicle networks 254. As some examples, the vehicle network 254 may include, but is not limited to, one or more of a controller area network (CAN), Ethernet, ultra-wideband (UWB), and media oriented systems transport (MOST).

[0024] The charging controller 252 of the vehicle 112 can be configured to control the charging of the vehicle battery 124. The charging controller 252 can be configured to communicate with the EVSE 138 (charger) to coordinate vehicle charging via a charging cable 256 that supports data communication. Alternatively, the charging controller 252 can be configured to communicate with the EVSE 138 via a wireless connection (not shown). Additionally or alternatively, the system can be configured to use the mobile device 222 to communicate vehicle information to the EVSE 138 via the wireless connection 258 with or without the involvement of the vehicle charging controller 252. The vehicle 112 and the mobile device 222 can also be configured to communicate with a remote server 259 via corresponding wireless transceivers to obtain various information.

[0025] The EVSE 138 may include one or more processors 260 configured to execute instructions, commands, and other programming that support the processes described herein. As an example, the EVSE 138 may be configured to execute instructions of the station software 262 stored in the storage device 264 to provide functionality such as activation / deactivation of charging, price selection, processing payments, and wireless communications with various digital entities. The EVSE 138 may be provided with an HMI control 266 configured to provide interaction with a user.

[0026] The EVSE 138 may include a wireless transceiver 268 that communicates with an NFC controller 270 , a radio frequency identification (RFID) controller 272 , a Bluetooth controller 274 , a Wi-Fi controller 276 , and other controllers configured to communicate with a compatible wireless transceiver 226 of the vehicle 112 and / or a compatible wireless transceiver 232 of the nomadic device 222 .

[0027] refer to Figure 3 , shows an exemplary flow chart of a process 300 for charging a vehicle according to an embodiment of the present disclosure. The process 300 provides a method for charging a vehicle more economically and flexibly by allowing a vehicle user to customize charging preferences while taking into account battery aging caused by DC fast charging. Continue to refer to Figure 1 and Figure 2, the process 300 may be implemented individually or collectively via one or more of the EVSE 138, the charging controller 252 of the vehicle 112, and / or the server 259. For simplicity, the following description will be made with reference to the EVSE 138. At operation 302, in response to detecting that the vehicle 112 is connected to the EVSE connector 140 via the charging port 142, the EVSE 138 establishes data communication with the vehicle 112 to prepare for an upcoming charging event. As discussed above, the charging cable 256 may be configured to support a data communication protocol and thus enable wired communication between the EVSE 138 and the charging controller 252 of the vehicle 112. Additionally or alternatively, data communication may be established between the EVSE 128 and the vehicle 112 via a wireless connection through the wireless transceivers 268, 226 of each respective device. Additionally or alternatively, the EVSE 138 may establish wireless data communication with a mobile device 222 associated with the vehicle 112.

[0028] At operation 304, the EVSE 138 receives vehicle information via previously established data communications. The vehicle information may include various information / data related to the vehicle 112 that may be used to assess vehicle charging. For example, the vehicle information may include the SOC of the traction battery 124, which may be used to determine the amount of energy required by the vehicle. The vehicle information may also include the vehicle make / model and the charging power configurations (e.g., charging powers) supported by the vehicle 112, which may be used to determine one or more charging powers applicable to the vehicle 112. The vehicle information may also include battery health and temperature information of the traction battery 124, which may be used to adjust the charging power.

[0029] As discussed above, the present disclosure allows vehicle users to customize the charging experience based on user preferences. At operation 306, the EVSE 138 receives a charging requirement for the current charging event specified by the user. The charging requirement may be received from the vehicle 112 and / or a mobile device 112 associated with the vehicle 112. The charging requirement may specify the desired outcome of a charging event defined by the user. For example, the charging requirement may include a desired target SOC at the end of a charging event specified by the user. The charging requirement may also include a maximum duration for the charging event that the user is willing to wait for. The charging requirement may also include a maximum budget for the charging event that the user is willing to pay. For example, the charging requirement may include a target SOC of 80% (starting from the current 30%), with a maximum duration of 20 minutes and a maximum budget of $20.

[0030] The charging requirement may also include a battery aging threshold within which battery aging caused by the current charging event is allowed. As discussed above, DC fast charging may cause degradation of battery health due to the heat generated by the high current. Battery aging may be quantified in various ways. For example, battery aging may be quantified in the form of a percentage of total battery capacity loss (e.g., 0.01% of the maximum capacity per charge). Additionally or alternatively, battery aging may be quantified in the form of a monetary value calculated based on the amount of capacity loss. Continuing with the above example, if the total value of the traction battery 124 is defined as $10,000, a 0.01% capacity loss may be converted to the equivalent of approximately $1.00 monetary depreciation of the traction battery 124. Battery aging (particularly in the form of monetary depreciation) may be considered as part of the maximum price offered by the vehicle. For example, if a user pays $30 for a fast charge and incurs a $2.00 battery monetary depreciation during the fast charge, the actual total expense amount associated with the fast charge event is $32 instead of $30. Therefore, the user's maximum budget will be at least $32 to qualify for the current charging event.

[0031] At operation 308, the EVSE 138 uses both the vehicle information and the previously received charging requirements to determine one or more candidate charging options. Depending on the specific situation, more than one candidate charging option may be determined. Each candidate charging option may include various characteristics associated with a planned charging event that meets the charging requirements specified by the user. For example, a charging option may include one or more charging powers that meet both the user's time and budget requirements at various stages of the charging event. Typically, a charging event may start with a higher charging power at the beginning of the charging event and gradually reduce the charging power based on the expected and real-time feedback from the traction battery 124 during the duration of the charging event. The change in charging power may affect the charging duration, which in turn may result in a different total price. In addition, different charging powers may also result in different battery aging. At operation 310, the EVSE 138 determines the battery aging of each candidate charging option and associates the battery aging with the corresponding charging option. Therefore, each charging option may be associated with a price, a charging duration, and a battery aging value (aging parameter). Battery aging can be determined and calculated by considering various factors. As a few non-limiting examples, battery aging can be determined using factors such as expected heat and / or temperature predicted using the charging power and its corresponding duration. Battery aging may be further determined using current and / or expected ambient temperatures during a charging event measured locally or received from server 259. Battery aging may be further determined using the current health of traction battery 124. As a general rule, lower charging powers may be associated with reduced amounts of battery aging, while higher charging powers may be associated with increased amounts of battery aging. In one example, over a given time period, a 75 kW charging power may be associated with nearly $0.00 battery aging, while 125 kW and 150 kW may be associated with monetary values ​​of $1.00 and $1.25 battery aging.

[0032] At operation 312, the EVSE 138 determines whether the aging value is within the aging threshold specified in the user requirements. If the answer is no, indicating that the aging associated with one or more candidate charging options is unacceptable, the process proceeds to operation 314, and the EVSE 138 reduces the planned charging power and re-determines one or more new charging options. In general, the reduced charging power can reduce the heat generated during charging and thus reduce battery aging. If the answer to operation 312 is yes, the process proceeds to operation 316, and the EVSE 138 presents options to the user to select from. The EVSE 138 can present the options via the HMI control 266. In addition or alternatively, the EVSE 138 can output the charging options to the vehicle 112 and / or the mobile device 222 for presentation to the user. The charging options may include various information associated with each option. For example, the user may be presented with charging options (including the total price, charging duration, and battery aging value associated with each option), and the user is asked to select from one of the options. In response to receiving user input indicating a user selection of one of the candidate charging options, the process proceeds to operation 318 and the EVSE 138 charges the vehicle based on the selected charging option.

[0033] Additionally or alternatively, the EVSE 138 may be configured to perform automatic decision making when multiple charging options are available without presenting each option to the user. More specifically, the user may pre-define a cost threshold that enables the EVSE 138 and / or the vehicle 112 to automatically select one of the eligible options without requiring user input each time the vehicle 112 is connected to the EVSE 138. The cost threshold may take into account not only the price paid for charging, but may also take into account the battery aging cost and the additional time the user waits for charging. For example, the total cost of each charging option may be determined using the following equation:

[0034] Cost = t*p+C battery+u*a

[0035] The above equation takes into account three factors to evaluate the total cost. The first factor t*p represents the price paid for charging for the corresponding option (the cost of electricity for charging). t represents the time required to charge the vehicle for the option, and p represents the charging rate for the option (e.g., price per minute). The second factor c 电池represents the monetary depreciation of the traction battery 124 associated with the charging option (traction battery aging cost). The third factor u*a represents the associated time cost of the user waiting for the vehicle to complete charging. The time cost can be presented and evaluated in various ways. In this example, the time cost can be evaluated in the form of additional time relative to the fastest charging option used as a reference. u represents a user-defined value representing the user's hourly rate ($20 per hour), and a represents the additional time of the corresponding option compared to the fastest charging time. For example, if the EVSE 138 determines that the fastest charging time is 30 minutes and the current option takes 45 minutes to complete, the additional 15 minutes will result in a time cost of $5 (i.e., $20*0.25 hours per hour). In the case of determining the total cost of each option, the EVSE 138 can be configured to automatically select the charging option with the lowest cost without requiring user input each time.

[0036] The algorithm, method or process disclosed herein can be delivered to or implemented by a computer, a controller or a processing device, which may include any dedicated electronic control unit or a programmable electronic control unit. Similarly, the algorithm, method or process can be stored in various forms as data and instructions that can be executed by a computer or a controller, including but not limited to information permanently stored on a non-writable storage medium such as a read-only memory device and information that can be changed and stored on a writable storage medium such as an optical disk, a random access memory device or other magnetic and optical media. The algorithm, method or process can also be implemented by a software executable object. Alternatively, suitable hardware components can be used, such as a combination of an application-specific integrated circuit, a field programmable gate array, a state machine or other hardware components or devices, or firmware, hardware and software components to implement the algorithm, method or process in whole or in part.

[0037] Although exemplary embodiments are described above, these embodiments are not intended to describe all possible forms covered by the claims. The words used in the specification are descriptive rather than limiting, and it should be understood that various changes can be made without departing from the spirit and scope of the present disclosure. The words a processor and multiple processors, for example, are interchangeable herein, as are the words a controller and multiple controllers.

[0038] As previously described, the features of the various embodiments may be combined to form additional embodiments of the invention that may not be explicitly described or shown. Although various embodiments may have been described as providing advantages or being preferred over other embodiments or prior art implementations with respect to one or more desired characteristics, it will be appreciated by those of ordinary skill in the art that one or more features or characteristics may be compromised to achieve desired overall system properties, depending on the specific application and implementation. These properties may include, but are not limited to, strength, durability, marketability, appearance, packaging, size, serviceability, weight, manufacturability, ease of assembly, and the like. Thus, embodiments described as being less desirable than other embodiments or prior art implementations with respect to one or more characteristics are not outside the scope of this disclosure and may be desirable for a particular application.

[0039] According to the present invention, a vehicle is provided, the vehicle having: a traction battery; and a controller programmed to: in response to a request for DC fast charging of the traction battery at a charging station providing a plurality of DC fast charging rates, generate an output for only each of the rates corresponding to an aging parameter of the traction battery that is less than a threshold, the output indicating a cost of charging the traction battery at the rate, each of the plurality of DC fast charging rates having a cost per unit time that increases as the rate increases; and charge the traction battery at the selected one of the rates.

[0040] According to one embodiment, the controller is further programmed to automatically select one of the rates based on user defined criteria for identifying the selected one of the rates.

[0041] According to one embodiment, the output further indicates a duration of charging the traction battery at the rate.

[0042] According to one embodiment, the cost includes a portion representing a value per unit of time for the user.

[0043] According to one embodiment, the controller is further programmed to receive an input defining a value per unit of time for the user.

[0044] According to one embodiment, the cost comprises a portion representing the product of a value per unit of time for the user and a difference between a charging duration at the rate and a charging duration at a maximum of the rates corresponding to the aging parameter less than the threshold.

[0045] According to one embodiment, the controller is further programmed to receive an input defining the threshold value.

[0046] According to the present invention, a method comprises, after receiving a request for DC fast charging of a traction battery at a charging station that provides a plurality of DC fast charging rates, charging the traction battery at one of the rates automatically selected based on a total cost such that the total cost is less than a threshold cost, the total cost including a portion representing a cost of electricity for the charging, a cost of time for a user of the charging, and a cost of aging of the traction battery of the charging, each of the plurality of DC fast charging rates having a cost per unit of time that increases as the rate increases.

[0047] In one aspect of the invention, the method includes receiving an input defining the threshold cost.

[0048] In one aspect of the present invention, the user's time cost is the product of the user's per unit time value and the duration of the charging.

[0049] In one aspect of the invention, said traction battery aging cost is a function of said one of a duration and said rate of said charging.

[0050] In one aspect of the invention, in response to a state of charge of the traction battery exceeding a threshold state of charge, an output is generated indicating a recommendation to switch to a non-DC fast charge.

[0051] According to the present invention, a vehicle control system is provided having: a controller programmed to charge a traction battery at one of a plurality of DC fast charge rates, the one of the plurality of DC fast charge rates being selected such that the one rate corresponds to an aging parameter of the traction battery that is less than a threshold, the aging parameter being based on a duration of the charging.

[0052] According to one embodiment, the controller is further programmed to charge at a rate selected such that a total cost of the charging is less than a threshold cost, and wherein the total cost includes a portion representing a cost of electricity for the charging, a cost of time for a user of the charging, and a cost of aging of a traction battery for the charging.

[0053] According to one embodiment, the user's time cost is the product of the user's per-unit time value and the duration.

[0054] According to one embodiment, said traction battery aging cost is a function of said duration and said one of said rates.

[0055] According to one embodiment, the total cost is user defined.

Claims

1. A vehicle comprising: Traction batteries; as well as A controller, the controller being programmed to: generating, in response to a request for DC fast charging of a traction battery at a charging station that provides a plurality of DC fast charging rates, an output only for each of the rates that corresponds to an aging parameter of the traction battery that is less than a threshold, the output indicating a cost of charging the traction battery at the rate; as well as The traction battery is charged at a selected one of the rates. 2 . The vehicle of claim 1 , wherein the controller is further programmed to automatically select one of the rates based on user-defined criteria for identifying the selected one of the rates.

3. The vehicle of claim 1 wherein the output further indicates a duration of charging the traction battery at the rate. The vehicle of claim 1 , wherein the cost includes a portion representing a value per unit of time for a user.

5. The vehicle of claim 4, wherein the controller is further programmed to receive an input defining a value per unit of time for the user.

6. The vehicle of claim 1 , wherein the cost includes a portion representing a product of a user's value per unit of time and a difference between a charging duration at the rate and a charging duration at a maximum of the rates corresponding to the aging parameter being less than the threshold.

7. The vehicle of claim 1 wherein the controller is further programmed to receive an input defining the threshold.

8. A method comprising: After receiving a request for DC fast charging of a traction battery at a charging station that provides a plurality of DC fast charging rates, charging the traction battery at one of the rates automatically selected based on a total cost such that the total cost is less than a threshold cost, the total cost including a portion representing a cost of electricity for the charging, a cost of time for a user of the charging, and a cost of aging of the traction battery of the charging, each of the plurality of DC fast charging rates having a cost per unit of time that increases as the rate increases.

9. The method of claim 8, further comprising receiving an input defining the threshold cost.

10. The method of claim 8, wherein the user's time cost is the product of the user's per unit time value and the duration of the charging.

11. The method of claim 8 wherein said traction battery aging cost is a function of said one of a duration of said charging and said rate. 12 . The method of claim 8 , generating an output indicative of a recommendation to switch to non-DC fast charging in response to the state of charge of the traction battery exceeding a threshold state of charge.

13. A vehicle control system, comprising: a controller programmed to charge a traction battery at one of a plurality of DC fast charge rates, the one of the plurality of DC fast charge rates being selected such that the one rate corresponds to an aging parameter of the traction battery that is less than a threshold, the aging parameter being based on a duration of the charging.

14. The vehicle control system of claim 13, wherein the controller is further programmed to charge at a rate selected so that a total cost of the charging is less than a threshold cost, and wherein the total cost includes portions representing a cost of electricity for the charging, a cost of time for a user of the charging, and a cost of aging of a traction battery for the charging. 15 . The vehicle control system of claim 14 , wherein the user's time cost is a product of the user's per-unit time value and the duration.

Images