Method for Adjusting a Battery on Demand When Not Charging

Abstract

A method according to an exemplary aspect of the present disclosure includes, among other things, conditioning a battery of an electric vehicle in response to an operator's request for improved performance at the expense of reduced driving range when not charging. An electric vehicle system according to an exemplary aspect of the present disclosure further includes a battery, a motor configured to receive power from the battery to drive wheels, and a system control device that generates a control signal for conditioning the battery in response to an operator's request for improved performance at the expense of reduced driving range when not charging.

Description

Technical Field

[0001] The present disclosure relates to a method and system for an electric vehicle, where a battery can be adjusted when not charging in response to an operator's request for improved performance at the expense of reduced driving range. Background Art

[0002] The need to reduce fuel consumption and emissions of motor vehicles is well known. Accordingly, vehicles that reduce or completely eliminate dependence on internal combustion engines are being developed. Electric vehicles are one type of vehicle currently being developed for this purpose. Generally, electric vehicles differ from conventional motor vehicles in that they are selectively driven by one or more motors powered by batteries. In contrast, conventional motor vehicles rely entirely on internal combustion engines to drive the vehicle.

[0003] High-voltage battery packs for powering motors and other electrical loads typically include multiple battery assemblies or battery arrays, which include multiple interconnected battery modules composed of battery cells. The power output of these high-voltage batteries is a function of various factors, one of which is the battery temperature. At extreme hot and cold ambient temperatures, the ability of the battery to charge and discharge may be limited. Since there is no engine to compensate for the loss of battery power, this problem becomes more critical for Battery Electric Vehicles (BEVs). Thus, these reductions in charge and discharge power limits reduce the vehicle's performance and drivability. Summary of the Invention

[0004] A method according to an exemplary aspect of the present disclosure includes, among other things, adjusting a battery of an electric vehicle when not charging in response to an operator's request for improved performance at the expense of reduced driving range.

[0005] In another non-limiting embodiment of the foregoing method, the method includes determining the state of the battery to determine the amount of energy required to bring the battery to a desired performance capacity level.

[0006] In another non-limiting embodiment of any of the foregoing methods, the method includes comparing at least one of a battery temperature and a state of charge of the battery with a threshold to determine the state of the battery.

[0007] In a further non-limiting embodiment of any of the foregoing methods, the method includes estimating the impact on driving range based on the amount of energy required to bring the battery to a desired performance capacity level.

[0008] In another non-limiting embodiment of any of the foregoing methods, the method includes communicating to the operator an estimated driving range available in the event the battery is adjusted to a desired performance capacity level.

[0009] In a further non - limiting embodiment of any of the foregoing methods, the estimating step includes defining a plurality of performance levels and estimating the impact of each performance level on the driving range based on the amount of energy required to bring the battery to each performance level.

[0010] In another non - limiting embodiment of any of the foregoing methods, the method includes communicating to the operator the estimated driving range available for each performance level.

[0011] In a further non - limiting embodiment of any of the foregoing methods, the method includes adjusting the battery in response to an affirmative request from the operator for improved performance at the expense of reduced driving range.

[0012] In another non - limiting embodiment of any of the foregoing methods, the adjusting step includes heating or cooling the battery.

[0013] In a further non - limiting embodiment of any of the foregoing methods, the electric vehicle comprises a battery electric vehicle or a plug - in hybrid electric vehicle.

[0014] A method according to another exemplary aspect of the present disclosure includes, among other things, generating an operator prompt in response to the next use or travel time of the electric vehicle or in response to the electric vehicle not being plugged in, the operator prompt allowing the operator to approve adjusting the battery of the electric vehicle for improved performance at the expense of reduced driving range.

[0015] In another non - limiting embodiment of any of the foregoing methods, the method includes determining the state of the battery to determine the amount of energy required to bring the battery to a desired performance capacity level.

[0016] In another non - limiting embodiment of any of the foregoing methods, the method includes comparing at least one of the battery temperature and the state of charge of the battery with a threshold to determine the state of the battery.

[0017] In another non - limiting embodiment of any of the foregoing methods, the method includes estimating the impact on the driving range based on the amount of energy required to bring the battery to a desired performance capacity level.

[0018] In another non - limiting embodiment of any of the foregoing methods, the method includes communicating to the operator the estimated driving range available if the battery is adjusted to the desired performance capacity level.

[0019] In another non - limiting embodiment of any of the foregoing methods, the method includes adjusting the battery in response to the operator's request for improved performance at the expense of reduced driving range.

[0020] A system according to another exemplary aspect of the present disclosure includes, among other things, a battery, an electric motor configured to receive power from the battery to drive the wheels, and a system control device that generates a control signal for conditioning the battery when not charging in response to a request for improved performance at the expense of reduced driving range.

[0021] In another non-limiting embodiment of the foregoing system, the system includes an interface configured to allow an operator to communicate a usage schedule to the system control device, and wherein the system control device is configured to identify the next usage or travel time, and if the next usage or travel time is during a non-charging state, generate an operator prompt that allows the operator to select an increased performance mode at the expense of reduced driving range.

[0022] In any further non-limiting embodiment of the foregoing system, the system control device determines the state of the battery to determine the amount of energy required to bring the battery to a desired performance capacity level, estimates the impact on driving range based on the energy requirement for conditioning the battery, and communicates to the operator the estimated driving range available if the battery is conditioned to the desired performance capacity level.

[0023] In another non-limiting embodiment of any of the foregoing systems, the system includes a heating system and a cooling system, wherein the system control is configured to, when not charging and in response to an operator's selection of improved performance capacity, activate the heating or cooling system to bring the temperature of the battery within a desired range for achieving the desired performance capacity level at the next usage or travel time.

[0024] The embodiments, examples, and alternatives of the foregoing paragraphs, claims, or the following description and drawings, including any of their respective aspects or individual features that can be taken independently or in any combination. Features described in connection with one embodiment apply to all embodiments unless the features are incompatible.

[0025] In light of the following detailed description, various features and advantages of the present disclosure will become apparent to those of ordinary skill in the art. The accompanying drawings, which are incorporated in and constitute a part of this specification, can be briefly described as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 An electric vehicle and a charging station are schematically shown;

[0027] Figure 2 is a flowchart showing a method for preconditioning a battery of an electric vehicle when not charging. DETAILED DESCRIPTION

[0028] The present disclosure details exemplary methods for conditioning a battery of an electric vehicle in response to an operator's request for improved performance at the expense of reduced driving range when not charging. These and other features are discussed in more detail in the following paragraphs of this detailed description.

[0029] Figure 1 An example electric vehicle 10 is schematically shown including a battery 12, an electric motor 14, and a pair of wheels 16. The electric motor 14 can receive electrical power from the battery 12. The electric motor 14 converts the electrical power into torque to drive the wheels 16. In some embodiments, the battery 12 is a high-voltage traction battery.

[0030] The example electric vehicle 10 is a fully electric vehicle, i.e., a battery electric vehicle (BEV). In other examples, the electric vehicle 10 is a hybrid electric vehicle or a plug-in hybrid electric vehicle (PHEV) that can selectively replace the electric motor with an internal combustion engine or drive the wheels 16 with torque provided by an internal combustion engine in addition to the electric motor. Other electric vehicles with fuel cells are also important in terms of thermal management.

[0031] The battery 12 will periodically need to be recharged. A charging station 18 can provide electrical power to recharge the battery 12. The charging station 18 includes a cable assembly 20 that can engage a port 22 of the electric vehicle 10 to electrically couple the electric vehicle 10 to the charging station 18. When the electric vehicle 10 and the charging station 18 are electrically coupled, electrical power can move from a grid power source 24 to the electric vehicle 10. The electrical power from the grid power source 24 recharges the battery 12.

[0032] The example electric vehicle 10 includes a system for controlling the operation of the battery 12 and the electric motor 14 and for interfacing with an operator of the vehicle 10. The system includes a controller 30 and an operator interface 32 that communicate with each other. The controller 30 can include a processor, a memory, and one or more input and / or output (I / O) device interfaces communicatively coupled via a local interface. The local interface can include, for example and without limitation, one or more buses and / or other wired or wireless connections. The local interface can have other elements, which are omitted for simplicity, such as controllers, buffers (caches), drivers, repeaters, and receivers for implementing communication. In addition, the local interface can include address, control, and / or data connections for enabling proper communication between the above components.

[0033] The controller 30 can be a hardware device for executing software, in particular software stored in a memory that can include one or more individual programs, each program including an ordered list of executable instructions for implementing logical functions. The controller 30 can be a custom or commercially available processor, a central processing unit (CPU), an auxiliary processor among several processors associated with a computing device, a semiconductor-based microprocessor (in the form of a microchip or chipset), or generally any device that executes software instructions. The memory can include any one or combination of volatile memory elements (e.g., random access memory (RAM), such as dynamic RAM (DRAM), static RAM (SRAM), synchronous dynamic RAM (SDRAM), video RAM (VRAM), etc.) and / or non-volatile memory elements (e.g., read-only memory (ROM), hard disk drive, magnetic tape, compact disc read-only memory (CD-ROM), etc.).

[0034] The interface 32 can include various input and output devices that can communicate with the controller input and output interfaces. The interface 32 can be, for example, a touch screen within the vehicle 10 through which information can be conveyed to the operator or through which the operator can communicate with the controller 30. Additionally, the interface 32 can also include a wireless communication interface through which the vehicle controller 30 and the operator can communicate via a mobile device such as a smart phone or a tablet computer or, for example, an Internet browser.

[0035] The battery 12 is an exemplary electric vehicle battery. The battery 12 can be a high-voltage traction battery pack including a plurality of battery assemblies (i.e., a battery array or a group of battery cells) capable of outputting electricity to operate the motor 14. In one non-limiting embodiment, the electric vehicle 10 operates in an electric vehicle (EV) mode in which the motor 14 is used for vehicle propulsion, thereby consuming the state of charge of the battery 12 to its minimum allowable value under certain driving modes / cycles.

[0036] In one example, when the vehicle is not in use, the operator preferably places the wire 20 in the charging port 22 so that the charging station 18 can replenish the depleted battery power. Optionally, there are wireless charging systems that do not require a plug connection for charging. However, typically during use, the vehicle 10 is parked in a location that does not include a charging station, which means the vehicle is not being charged.

[0037] As discussed above, an exemplary method of the present disclosure is directed to a method of conditioning battery 12 of BEV 10 to allow an operator to select a mode that provides higher vehicle performance at the expense of reduced driving range. In one example, controller 30 determines the battery state to determine the amount of energy required to bring the battery to a desired performance capacity level. In one example, the state of the battery is determined based on the state of charge of the battery and / or the battery temperature. For example, the desired performance level may be based on the desired speed capability, acceleration capability, etc. As Figure 2 shown, controller 30 first detects when the Next Usage Time (NUT) or travel time, as shown at 100, is available. In one example, the operator communicates with controller 30 via interface 32 to identify one or more travel times / NUTs scheduled for the vehicle 10 on a daily or multi-day basis. When the vehicle is charging, controller 30 can then initiate battery heating or cooling based on when the operator plans to next use the vehicle, such that a desired vehicle performance level can be achieved. However, if the next usage time occurs while the vehicle is not charging, controller 30 traditionally does not initiate battery heating or cooling for performance improvement because this can have an adverse effect on the vehicle's driving range.

[0038] However, as the driving range of BEV 10 continues to be extended, it is desirable to provide the operator with the option of improved performance rather than increased driving range. Once it is determined that the next usage time occurs while the vehicle is not charging, controller 30 begins an analysis to determine if the battery can be conditioned as shown at 102. As shown at 104, the method first determines if vehicle 10 is in a non-charging situation. If the vehicle is in a non-charging situation, controller 30 then determines the current state of battery 12. For example, controller 30, as shown at 106, determines if the available power from battery 12 is limited due to the current temperature of battery 12. In one example, step 106 has two temperature thresholds, which include a first threshold T1 and a second threshold T2, where below the first threshold T1 the battery needs heating and above the second threshold T2 the battery needs cooling. It should be noted that the temperature value of T1 is lower than T2. In other words, if the battery temperature is between the two thresholds, no thermal management / conditioning is required. As shown at 108, controller 30 can also determine if the available energy from battery 12 is limited due to the state of charge C of the battery, where the state of charge C must be greater than a threshold C1. In other words, the current battery temperature and the current state of charge are compared with the respective thresholds to determine if conditioning is required to place the battery in an appropriate state to provide the desired performance level at the next "travel time".

[0039] If the controller 30 determines that the battery temperature meets the threshold requirements and the state of charge of the battery meets the threshold, it can do so because the current state of the battery is sufficient to achieve the desired performance level. For example, if it is determined that the battery temperature is within a predetermined temperature range defined by T1 and T2, and the state of charge of the battery is higher than a predetermined state of charge threshold C1, then a determination is made as shown at 110 regarding the amount of energy required to place the battery 12 under conditions that provide the desired performance level. In one example, the amount of energy required is based on providing a full or maximum performance level for the vehicle. In another example, multiple performance levels are identified and the amount of energy is determined for each performance level.

[0040] As shown at 112, based on this determination, the controller 30 will estimate the remaining driving range of the vehicle 10 in the case where the battery 12 is to be conditioned for a desired increased performance level. For example, the controller 30 will determine the currently available driving range and the estimated impact on the driving range, i.e., the reduction in driving range, that will occur if the operator selects to condition. As shown at 114, the controller 30 then prompts the operator to select between conditioning the battery 1 and a limited or increased performance mode based on the estimated impact on the vehicle's driving range. The controller 30 does this by communicating information to the operator via the interface 32. In one example, the information includes the amount by which the driving range will be reduced and the driving range available if conditioning the battery 12 will occur.

[0041] As shown at 116, if the operator affirmatively selects the increased performance level at the expense of reducing the driving range, then the controller 30 will then determine the temperature at which the battery 12 needs to be in order to achieve the desired performance level. In one example, the vehicle includes a heating system 40 and a cooling system 42 controlled by the controller 30( Figure 1 ). As Figure 2 shown at 118, if heating is required, the controller 30 will issue a control signal to activate the heating system 40. As shown at 120, if cooling is required, the controller 30 will issue a control signal to activate the cooling system 42. Subsequently, the battery 12 is cooled or heated until the desired temperature range is reached. Any type of heating or cooling system can be used to heat / cool the battery 12.

[0042] As shown at 122, if heating is required, the controller 30 will identify the target battery coolant temperature. Then, as shown at 124, the controller 30 will determine the heater duty cycle to achieve the target battery coolant temperature. The controller 30 will then issue a control signal to control valves, pumps, and / or other heating system components to perform the heater duty cycle as shown at 126.

[0043] As shown at 128, if cooling is required, the controller 30 will identify the target battery coolant temperature. Then, as shown at 130, the controller 30 will determine the cooling duty cycle to achieve the target battery coolant temperature. Then, as shown at 132, the controller 30 will issue control signals to valves, pumps, and / or other air conditioning system components to perform the cooling duty cycle.

[0044] This method is useful for situations where the vehicle is not charging for an extended period of time in high or low temperature environments. For example, if the operator drives to the airport for a trip, the vehicle may be in a non-charging state for several days. The operator may have communicated to the controller 30 the estimated travel time / NUT when the operator returns from the trip. The controller 30 can then determine the current state of the battery based on this travel time / NUT and offer the operator options with an available increased performance level.

[0045] In this example, the operator may have indicated that the operator is planning to return home upon arrival at the airport. If the vehicle has been in a very cold environment for several days, the controller 30 can then determine the energy required to heat the battery to place the battery within a temperature range that provides one or more different performance levels. The controller 30 can also determine the impact on the driving range due to the energy required to thermally condition the battery. The controller can then communicate to the operator how much driving range is available for each performance level and allow the user to approve or disapprove the conditional strategy.

[0046] While different non-limiting embodiments are shown as having specific components or steps, the embodiments of the present disclosure are not limited to those specific combinations. Some components or features in any non-limiting embodiment can be used in combination with features or components from any other non-limiting embodiment.

[0047] It should be understood that like reference numerals in several figures represent corresponding or similar elements. It should be understood that although a particular component arrangement is disclosed and shown in these exemplary embodiments, other arrangements may also benefit from the teachings of the present disclosure.

[0048] The above description should be construed as illustrative and not as any limitation. Those of ordinary skill in the art will understand that certain modifications may fall within the scope of the present disclosure. For these reasons, the following claims should be studied to determine the true scope and content of the present disclosure.

Claims

1. A method for adjusting a battery of an electric vehicle, comprising: Determining a next usage time when the electric vehicle is not charging; Determining a current available driving range of the electric vehicle; Estimating an impact of increasing a performance capacity level on the current available driving range; Providing a choice of an increased performance mode to an operator based on the estimated impact on the current available driving range; Adjusting the battery of the electric vehicle in response to the operator's selection of the increased performance mode when not charging.

2. The method according to claim 1, comprising: Determining a state of the battery to determine an amount of energy required to bring the battery to the increased performance capacity level.

3. The method according to claim 2, comprising: Comparing at least one of a battery temperature and a state of charge of the battery with a threshold to determine the state of the battery.

4. The method according to claim 2, comprising: Estimating an impact on the current available driving range based on the amount of energy required to bring the battery to the increased performance capacity level, and communicating to the operator an estimated driving range available when the battery is adjusted to the increased performance capacity level.

5. The method according to claim 4, wherein the estimating step includes: Defining a plurality of increased performance capacity levels and estimating an impact of each increased performance capacity level on the driving range based on the amount of energy required to bring the battery to each increased performance capacity level, and communicating to the operator an estimated driving range available for each increased performance capacity level.

6. The method according to claim 4, comprising: Adjusting the battery in response to the operator's selection of the increased performance mode, and the adjusting step includes heating or cooling the battery.

7. The method according to claim 1, wherein the electric vehicle includes a battery electric vehicle or a plug-in hybrid electric vehicle.

8. A method for adjusting a battery of an electric vehicle, comprising: Determining a next usage time when the electric vehicle is not charging; Determining a current available driving range of the electric vehicle; Estimating an impact of increasing a performance capacity level on the current available driving range; Providing a choice between a limited performance mode and an increased performance mode to an operator based on the estimated impact on the current available driving range; Generating an operator prompt when the electric vehicle is not charging, the operator prompt allowing the operator to approve adjusting the battery of the electric vehicle to achieve the increased performance mode.

9. The method according to claim 8, comprising: Determining a state of the battery to determine an amount of energy required to bring the battery to the increased performance capacity level, and comparing at least one of a battery temperature and a state of charge of the battery with a threshold to determine the state of the battery.

10. The method according to claim 9, comprising: Estimating an impact on the current available driving range based on the amount of energy required to adjust the battery, and communicating to the operator an estimated driving range available when the battery is adjusted to the increased performance capacity level.

11. The method according to claim 10, comprising: Adjusting the battery in response to an affirmative request from an operator for the increased performance mode.

12. An electric vehicle system, comprising: A battery, An electric motor configured to receive power from the battery to drive wheels, and A system control device configured to: Determine the next usage time when the electric vehicle is not charging; Determine the current available driving range of the electric vehicle; Estimate the impact of an increased performance capacity level on the current available driving range; Offer the operator a choice between a limited performance mode and an increased performance mode based on the estimated impact on the current available driving range; And Generate a control signal for adjusting the battery in response to a request from the operator for the increased performance mode when not charging.

13. The system according to claim 12, comprising: An interface configured to allow the operator to communicate a usage schedule to the system control device, and wherein the system control device is configured to: Generate an operator prompt that allows the operator to select the increased performance mode.

14. The system according to claim 13, Wherein: The system control device is configured to: Determine the state of the battery to determine the amount of energy required to bring the battery to the increased performance capacity level, Estimate the impact on the driving range based on the amount of energy required to adjust the battery, and Communicate to the operator the estimated driving range available if the battery is adjusted to the increased performance capacity level.

15. The system according to claim 14, comprising: A heating system and a cooling system, wherein the system control device is configured to, when not charging and in response to an operator's selection of the increased performance mode, activate the heating system or the cooling system to place the temperature of the battery within a desired range for achieving the increased performance capacity level for the next use or travel time.

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