Vehicle Power Management System

Abstract

The vehicle power management system includes a power source having a plurality of battery cells and switching to control electrical connection of the battery cells. The system is configured to measure electrical parameters to determine a power consumption demand and dynamically assign the battery cells to a primary group and an auxiliary group. The number of battery cells assigned to the auxiliary group depends on the power consumption demand. During the power consumption demand, the system controls the switching to electrically connect the battery cells assigned to the auxiliary group to supply power for the power consumption demand.

Description

[Technical field]

[0001] The present invention relates generally to a type of vehicle power management system designed to ensure that there is sufficient battery power for vehicle power consumption demands, such as cranking. [Background technology]

[0002] A vehicle's internal combustion engine is started using a starter motor that draws power from a battery source (typically a lead-acid battery) during ignition.

[0003] However, the battery power source may become too depleted (e.g., due to parasitic power draw of vehicle systems) to provide sufficient power to the starter motor, which may cause the vehicle to become inoperable and require a jump start, towing, etc.

[0004] Vehicles may have other power consumption requirements, such as to unlock and open the doors, etc. Electric vehicles have been known to become inaccessible when their batteries become too depleted to operate the doors.

[0005] SUMMARY OF THE PRESENT EMBODIMENT The present invention seeks to provide a vehicle power management system that overcomes or substantially ameliorates at least some of the shortcomings of the prior art, or at least to provide an alternative system.

[0006] Where any information of prior art is referred to herein, it should be understood that such reference does not constitute an admission that that information forms part of the common general knowledge in the art in Australia or any other country. Summary of the Invention

[0007] Provided herein is a vehicle power management system that includes a power source that includes a plurality of battery cells.

[0008] The system further includes switching for controlling the electrical connection of the battery cells.

[0009] The system is configured to dynamically allocate battery cells into primary and auxiliary groups.

[0010] The system is further configured to measure the electrical parameters to determine a power consumption requirement, and the number of battery cells assigned to the auxiliary group is dependent on the power consumption requirement.

[0011] During that power consumption demand, the system controls switching to electrically connect the battery cells assigned to the auxiliary group to provide power for the power consumption demand.

[0012] In this manner, the system of the present invention ensures that the battery cells assigned to a supplemental group always have sufficient charge to meet the determined power consumption requirements.

[0013] For example, with respect to an internal combustion engine vehicle power consumption requirement for cranking, the system may measure electrical parameters during cranking to determine the cranking power consumption requirement, and during cranking, the system controls switching to electrically connect the battery cells assigned to the auxiliary group to supply power to the starter motor to meet the determined cranking power consumption requirement.

[0014] In this manner, the system of the present invention ensures that the battery cells assigned to the auxiliary group always have sufficient charge for cranking.

[0015] In an embodiment, the number of battery cells assigned to the auxiliary group may further depend on configurations that may affect power consumption requirements during cranking, such as engine size and engine fuel type. For example, during initial installation, the system may be configured with a configuration setting for a 3L diesel engine.

[0016] In a further embodiment, the number of battery cells assigned to the auxiliary group is further dependent on a further measured parameter that may affect the power consumption demand during cranking. One such measured parameter may be temperature, for example, the system may be configured to add an additional battery cell to the auxiliary group for every 2° C. below 20° C.

[0017] In further embodiments, the number of battery cells assigned to the auxiliary group may further depend on calculation parameters that may affect the power consumption requirements during cranking. One such calculation parameter may be the battery life since battery cell efficiency decreases over time. Another such calculation parameter may be the time elapsed since the last cranking, which indicates cold or warm cranking.

[0018] In embodiments, the system may be configured to alternate the allocation of battery cells between the primary and auxiliary groups to spread out the duty cycle and extend the life of the power source. Battery cells may be reallocated after a certain number of crankings or after a period of time. In certain embodiments, the system may be configured to permanently reserve at least one cell for the auxiliary group, and thus not suffer from duty cycle degradation from use in the primary group.

[0019] During charging, the system may be configured to prioritize charging of battery cells assigned to auxiliary groups, and the system may measure the state of charge of the battery cells assigned to the auxiliary groups to control such prioritization.

[0020] In an embodiment, the system may be configured to detect cranking, such as by detecting a current above a threshold or a voltage below a threshold.

[0021] Preferably, the system is configured to switch the battery cells of the auxiliary group in a short period of time, such as less than 10 ms, or even less than 5 ms, so that the initial current inrush demand can be met. In an alternative embodiment, the power supply can be manually configured in cranking mode to switch the battery cells assigned to the auxiliary group when needed.

[0022] In some embodiments, the system is configured to measure the state of charge of the battery cells assigned to the primary group to determine if battery cells from the auxiliary group are needed, for example, if the state of charge of the primary group is sufficient to meet cranking power consumption demands, the system may reserve cells of the auxiliary group for later use.

[0023] In an embodiment, the system of the present invention takes the form of a portable vehicle battery with an internal controller that can be installed in a vehicle in a conventional manner.

[0024] In the case of an electric vehicle, power consumption requirements may relate to maintaining enough power to open and close the vehicle doors, to be able to drive a certain distance, or to keeping the vehicle in a "limp" mode for a certain duration.

[0025] Other aspects of the invention are also disclosed.

[0026] While any other form may be considered which may fall within the scope of the invention, preferred embodiments of the present disclosure will now be described, by way of example only, with reference to the accompanying drawings, in which: [Brief description of the drawings]

[0027] [Figure 1] 1 illustrates a block level system diagram of a vehicle power management system according to one embodiment. [Diagram 2] 4 illustrates an exemplary current draw during cranking. [Diagram 3] 4 illustrates an exemplary process by a system according to one embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] FIG. 1 shows a vehicle power management system 100 comprising a power supply 101 comprising a split-cell arrangement of multiple individual battery cells 102 .

[0029] The system 100 further includes switching 103 electrically connecting the battery cells 102. The switching 103 may include an electrical switch 104 for each battery cell 102. The electrical switches 104 may be high-rated MOSFET switches or the like. The battery cells 102 may be lead-acid based battery cells, although other battery technologies are envisioned, including lithium based battery cells 102.

[0030] According to the illustrated embodiment, the battery cells 102 are connected in parallel by switching 103. Each battery cell 102 may provide 12V to be compatible with the vehicle electrical system.

[0031] In an embodiment, the power source 101 may be a physical portable battery that may be installed in a vehicle in a conventional manner, having battery terminals 105. The terminals 105 may include a positive battery terminal 105A and a negative battery terminal 105B.

[0032] As shown, the negative battery terminal 105B may be connected to a common negative rail 106 of the battery cells 102. Additionally, the positive battery terminal 105A may be connected to a common positive rail 107 that interfaces with the switching 103.

[0033] In an alternative embodiment, the system 100 is integrally installed in the vehicle, such as at the time of manufacture. In this embodiment, the battery cells 102 themselves may be replaced as needed, but other components of the system 100 may remain installed.

[0034] The power source 101 may be used to provide electrical power to the vehicle, including for the vehicle's starter motor 108 during cranking. An ignition switch 109 may selectively interconnect the power source 101 and the starter motor 108.

[0035] The system 100 is configured to measure electrical parameters to determine power consumption requirements.

[0036] Thus, the system 100 is configured to dynamically allocate the battery cells 102 to the primary and auxiliary groups. The number of battery cells 102 allocated to the auxiliary group 102 depends on the power consumption requirements.

[0037] Thus, during this power consumption demand, the system 100 is configured to control the switching 103 to electrically connect the battery cells 102 assigned to the auxiliary group to provide power for the power consumption demand.

[0038] According to one embodiment, the power consumption demand is a cranking power consumption demand of an internal combustion engine vehicle, and the system 100 may measure electrical parameters during cranking to determine the cranking power consumption demand.

[0039] Thus, during cranking, the system 100 controls the switching 103 to electrically connect the battery cells 102 assigned to the auxiliary group to supply power to the starter motor 108 to meet the determined cranking power consumption demand.

[0040] In this manner, the system of the present invention ensures that the battery cells assigned to the auxiliary group always have sufficient charge for cranking.

[0041] In an embodiment, the system 100 may comprise a controller 110 configured to control the switching 103. The controller 110 comprises a processor 111 for processing digital data. The controller 110 may further comprise a memory device 112 operatively interfacing with the processor 111 via a system bus 113. The memory device 112 is configured to store data 114 and computer program code instructions. In use, the processor 111 fetches these computer program code instructions and associated data 114 from the memory device 112 for interpretation and execution of the computational control functions described herein.

[0042] The computer program code instructions may be logically divided into multiple computer program code instruction controllers 115. For example, one controller 115 may be used to measure electrical parameters to determine cranking power consumption demand. Another controller 115 may be used to dynamically allocate battery cells 102 between primary and auxiliary groups. A further controller 115 may be used to control the switching 103.

[0043] The controller 110 may include an I / O interface 116 for interfacing the switching 103 with other peripherals. The I / O interface 116 may be a digital and / or analog I / O interface 116.

[0044] In embodiments where power source 101 is a physical portable battery, the battery may have controller 110 installed therein. In this embodiment, controller 110 may take the form of a small, ruggedized microprocessor device suitable for such applications, such as a field programmable gate array (FPGA) based controller.

[0045] The system 100 may include an ammeter 117 that is used by the controller 110 to measure the amperes drawn during cranking. The controller 110 may use the current readings from the ammeter 117 to determine cranking power demand.

[0046] 2 shows an example current trend 138 during cranking, where the vertical axis represents current and the horizontal axis represents time. When the ignition switch 109 is closed at point 118, an inrush current over about 5 ms causes the current to reach a maximum plateau 119 at about 15 ms.

[0047] As the starter motor 108 begins to rotate, a series of current draw oscillations 120 at a frequency of approximately 2 Hz may be exhibited until the internal combustion engine is started, after which the current returns to zero at point 121 .

[0048] In additional or alternative embodiments, the system 100 may include at least one voltmeter 122. The controller 110 may obtain voltage readings from the voltmeter 122 during cranking to determine cranking power demands. In the illustrated embodiment, the system 100 includes a voltmeter 122 interfaced with each battery cell 102. In an alternative embodiment, the system 100 includes switching interfaced with each voltmeter 122 for each of the primary and auxiliary groups. In this manner, the system 100 may determine the state of charge of the auxiliary or primary group, as described in further detail below.

[0049] The data 112 may be organized using a look-up table that maps the measured current and / or voltage to a respective cranking power consumption demand, or the controller 110 may be configured to calculate the cranking power consumption demand using a formula using the current and / or voltage.

[0050] In a preferred embodiment, the controller 110 uses both the current and voltage to determine the total power draw during cranking and sets the cranking power draw demand accordingly. The controller 110 may calculate the cranking power draw demand using a safety factor, such as 10% above the measured total power draw.

[0051] In an embodiment, the controller 110 may be configured to measure cranking power consumption over multiple crankings and calculate the cranking power consumption requirement using a rolling average calculation. The rolling average calculation may be used to account for variability in power consumption requirements that may be affected over time by factors such as battery life, temperature, etc.

[0052] For example, in the winter when a colder engine consumes more power while cranking, a rolling average may gradually increase the cranking power consumption requirement as the seasons become colder and winterier, or gradually decrease the cranking power consumption requirement as the seasons become warmer and summerier.

[0053] The data 114 may include an assignment table that records which battery cells 102 are assigned to which groups. The assignment table is dynamically updated by the controller 115 over time.

[0054] In an embodiment, the number of battery cells 102 assigned to a supplemental group further depends on configuration settings that may affect power consumption requirements. For example, configuration settings may include engine size configuration settings, where larger engines require more power during cranking. As a further example, configuration settings may include fuel type, where diesel engines require more power during starting (including for coil preheating).

[0055] Thus, for example, during initial configuration, system 100 may be configured with configuration settings stored in data 114 that specify that power source 110 is to be installed on a 3L diesel engine. The lookup tables previously described that map voltage and / or current to respective cranking power demands allow for further mappings according to these configuration settings. For example, the lookup tables may include separate mappings for diesel engines as opposed to gasoline engines.

[0056] In an embodiment, the number of battery cells assigned to the auxiliary group further depends on the further measured parameter. Referring to FIG. 1, the system 100 may include a sensor 123. The controller 110 may read a signal from the sensor 123 to determine the further measured parameter.

[0057] In an embodiment, custom sensors 123 may be installed in the vehicle. In an alternative embodiment, controller 110 may operatively interface with vehicle management system 125, including reading various sensor data from vehicle management system 125. In yet another embodiment where power source 101 is a portable battery, required sensors (such as an ambient air temperature sensor) may be integrally installed in the power source.

[0058] In one embodiment, the sensor 123 is a thermometer since temperature can affect power consumption requirements during cranking, and thus the controller 110 can dynamically allocate more battery cells 102 to the auxiliary group in colder weather compared to warmer weather.

[0059] The further measured parameters may be used to vary the number of battery cells 110 assigned to the auxiliary groups according to the determined cranking power consumption requirements.

[0060] For example, for a particular vehicle for which the controller 110 has determined that 10 battery cells 102 should be reserved in the auxiliary group for cranking, the controller 110 may be programmed to increase the number of battery cells 102 assigned to the auxiliary group by one battery cell 102 for every 2° C. decrease below 20° C. Thus, at 0° C., the controller 110 will have assigned an additional 10 battery cells 102 to the auxiliary group in accordance with the determined cranking power consumption requirements, in addition to the 10 battery cells 102 already assigned to the auxiliary group.

[0061] In an embodiment, during initialization (such as after manufacture or installation), the controller 110 may enter an initial calibration stage, where these additional measurement parameters are instantiated by measurements using the associated sensors 123. Once these additional measurement parameters are calibrated, the controller 110 may store these measurement parameters in memory for subsequent lookup.

[0062] Periodically, the controller 110 may reinitialize these various measured parameters by taking further measurements. For example, some parameters, such as engine displacement, may not require reinitialization, while other parameters, such as ambient temperature, may.

[0063] In an embodiment, the number of battery cells assigned to the auxiliary group further depends on a calculation parameter that may affect the power consumption requirements during cranking.

[0064] One such calculation parameter may be the battery life, since the efficiency of the battery cells 102 decreases over time. For example, the controller 110 may be configured to add an additional battery cell 102 to the auxiliary group every six months after installation.

[0065] The controller 110 may interface with a user interface 124, which may include a digital display and / or push buttons. The user interface 124 may be used to reset a timer upon initial installation for calculation of elapsed time.

[0066] In a further embodiment, the calculated parameter is calculated as the time since the last cranking. For example, the controller 110 may be configured to reserve an additional five battery cells 102 for the auxiliary group if the vehicle was last started more than an hour ago. That is, when the engine was started recently and is therefore still warm, the starter motor 108 will have a lower power consumption requirement during cranking than if it had not been started for some time.

[0067] As alluded to above, the number of battery cells 102 assigned to the auxiliary groups according to cranking power consumption demands may vary formulaically according to measured and / or calculated parameters. Alternatively, the controller 110 may use the look-up table described above to calculate the variance of the number of battery cells 102 assigned to the auxiliary groups according to measured and / or calculated parameters.

[0068] In an embodiment, the controller 110 is configured to alternate the allocation of battery cells between the primary and auxiliary groups.

[0069] For example, after a certain number of crankings or after a certain period of time (e.g., one month), the controller 110 may reassign five battery cells 105 from the auxiliary group to the primary group and correspondingly reassign each of the five battery cells 105 from the primary group to the auxiliary group. Such a rotational assignment shares duty cycles among the battery cells 102, thereby extending the life of the power source 101.

[0070] However, in an embodiment, the controller 110 may be configured to reserve at least one battery cell 102 for the auxiliary group that is not assigned to the primary group, such that the at least one reserved battery cell 102 does not exhibit duty cycle degradation over time, thereby ensuring that at least one underutilized battery cell 102 remains in the auxiliary group.

[0071] In an embodiment, the system 100 is configured to detect cranking and control the switching 103 accordingly. For example, the controller 110 may use an ammeter 117 to detect when the current draw exceeds a threshold indicative of cranking. The controller 110 may reactively switch battery cells 102 from the auxiliary group, preferably in less than 5 ms, to meet the maximum current draw 119 demand shown in FIG. 2. Similarly, the controller 110 may use at least one voltmeter 122 to detect when the voltage drops below a threshold indicative of cranking.

[0072] In an alternative embodiment, the system is manually configurable into cranking mode and configured to control switching to electrically connect battery cells 102 assigned to auxiliary groups when the system 100 is in cranking mode.

[0073] For example, if the power source 101 takes the form of a portable battery, the user interface 124 may take the form of a toggle switch. During cranking, a user may flick the toggle switch to configure the portable battery into cranking mode such that the battery cells 102 assigned to the auxiliary group are switched in for cranking.

[0074] During charging of the power source 101, the system 100 may be configured to control the switching 103 to prioritize charging of the battery cells 102 assigned to the auxiliary group. The system 100 may be further configured to measure the state of charge of the battery cells 102 assigned to the auxiliary group.

[0075] For example, the controller 110 may be configured to detect charging when the current or voltage determined by the ammeter 117 or the at least one voltmeter 122 exceeds a threshold value. For example, the controller 110 may detect charging when the voltage detected by the at least one voltmeter exceeds 13 V.

[0076] The controller 110 may monitor the state of charge of each battery cell 102 to determine the state of charge of the battery cells 102. For example, the controller 110 may determine that a measured voltage less than 8V should be classified as a depleted state of charge. Thus, upon detecting the depleted battery cells 102 assigned to the auxiliary group using their respective voltmeters 122, the controller 110 may control the switching 103 to charge these depleted battery cells 102 first until it detects a voltage rise above, for example, 12.5V, and then the other cells 102 of the main group may be connected by the switching 103 for recharging.

[0077] In an embodiment, the controller 110 is configured to measure the state of charge of the battery cells 102 assigned to the primary group to determine whether to control the switching 103 to electrically connect the battery cells 102 assigned to the auxiliary group during cranking. For example, if the measured state of charge of the battery cells 102 assigned to the primary group indicates that the battery cells 102 are sufficient to meet cranking power consumption demands, the controller 110 may be configured not to switch the battery cells 102 assigned to the auxiliary group.

[0078] 3 illustrates an example process 126 that may be implemented by the system 100 in relation to cranking power consumption demand. In an embodiment, the process 126 is implemented by the controller 110.

[0079] The process begins at step 127. At step 128, the controller 110 may be configured with various configuration settings. These configuration settings may include the number of cells 120 of the power source 110 for the allocation table in the memory 112.

[0080] Additionally, these configuration settings may include the previously mentioned configuration settings that may affect power consumption requirements during cranking, such as engine size, fuel type, etc. Also, as alluded to above, these configuration settings may be used as part of a look-up table to map measured electrical parameters to respective cranking power consumption requirements.

[0081] In step 129, the controller 110 is configured to measure an electrical parameter 131 to determine the cranking power consumption demand.

[0082] As alluded to above, the controller 110 may use an ammeter 117 to measure current draw during cranking, and at least one voltmeter 122 to measure voltage during cranking, and preferably use both current and voltage to measure actual power consumption.

[0083] The controller 110 may be configured to integrate the current draw (i.e., calculate the area under the current draw trend 138) to measure the total current draw over time between the start of cranking 118 and the end of cranking 121. That is, the controller 110 may be configured to accurately measure ampere-hours for the required power consumption demand according to the measured current.

[0084] The controller 110 may then store the determined cranking power consumption requirement in the memory 112 .

[0085] As alluded to above, the controller 112 may increase the cranking power demand by a safety factor, such as 10%.

[0086] In step 130, the controller 110 dynamically assigns the battery cells 102 to subgroups.

[0087] As shown, in step 130, the controller 110 may further receive a sensor signal 132 from the sensor 123 to adjust the number of battery cells 102 assigned to the subgroups. As alluded to above, the sensor 123 may include a temperature sensor, with the controller 110 assigning more battery cells 102 to the subgroups with lower temperatures.

[0088] Also, in step 130, the controller 130 may perform calculations 133 to adjust the number of battery cells 102 assigned to the auxiliary groups. As alluded to above, these calculations 133 may be calculations that affect power consumption requirements during cranking, such as battery life and time since last cranking.

[0089] When assigning battery cells 102 to the primary and auxiliary groups, the controller 120 may perform a rotation decision 134 to determine whether to rotate battery cells between the two groups. As alluded to above, after a certain number of crankings (e.g., every 10 crankings) or after a certain period of time (e.g., every month), the controller 110 may reallocate a predetermined number of battery cells 102 from the auxiliary group to the primary group and correspondingly reallocate an equal number of battery cells 102 from the primary group to the auxiliary group.

[0090] Also at step 130, the controller 110 makes a decision 135 as to whether to reserve a particular battery cell 102 for a supplemental group.

[0091] In step 136, during cranking, the controller 110 controls the switching 103 to electrically connect the battery cells assigned to the auxiliary group to provide power for cranking.

[0092] As alluded to above, the controller 110 may determine the state of charge 137 of the battery cells assigned to the primary group to determine if the battery cells 102 assigned to the auxiliary group are required for cranking. That is, if the state of charge of the battery cells 102 assigned to the primary group is measured to be sufficient to meet cranking power consumption demands, the controller 103 may be programmed not to switch out the battery cells 102 assigned to the auxiliary group.

[0093] In further embodiments, the power consumption requirements may relate to other types of vehicle power consumption requirements, including for electric vehicles.

[0094] In this regard, the battery cells 102 may be used to power an electric motor of an electric vehicle. For example, the battery cells 102 assigned to the primary group may be used to power the vehicle's electric motor, and the battery cells 102 assigned to the auxiliary group may be held in reserve to meet the measured power consumption needs of the electric vehicle.

[0095] For example, the power consumption requirement may relate to maintaining residual power in the auxiliary group to meet a measured door mechanism power consumption requirement for unlocking and / or opening the door. This embodiment avoids a situation where the electric vehicle cannot be opened due to a depleted battery, resulting in the need for towing, etc.

[0096] According to this example, during unlocking or opening of the vehicle door, the controller 110 is configured to measure the power consumption requirement (e.g., in terms of voltage and / or current) for opening or unlocking the vehicle door. Thus, the controller 110 can dynamically assign the battery cells 102 to the auxiliary groups according to the determined power consumption requirement, such that if the door needs to be opened or unlocked despite the battery cells 102 assigned to the primary group being depleted, the auxiliary groups will have sufficient residual power to do so.

[0097] In a further embodiment, the power consumption requirement is related to a drivable range power consumption requirement.

[0098] According to this embodiment, the system 100 may measure power consumption during driving to determine the power consumption requirements necessary to drive the vehicle a certain distance.

[0099] For example, the controller 110 may measure the power consumption requirements of a vehicle's electric motor to determine the power consumption requirements for driving a distance of 50 km.

[0100] The power consumption requirement may be calculated by the controller 110 with reference to other parameters that may affect the range power consumption requirement, such as measured electrical circuit resistance, ambient temperature, drivetrain efficiency, vehicle mass, drag coefficient, rolling resistance, tire pressure, air conditioning system load, number of passengers, etc.

[0101] Thus, the controller 110 may be configured to assign battery cells 102 to auxiliary groups depending on the measured power consumption requirements for driving a certain distance. The amount of battery cells 102 assigned to the auxiliary groups may be adjusted according to these further measured parameters. For example, upon sensing that there are four passengers in the vehicle, the controller 110 may be configured to assign an additional two battery cells 102 to the auxiliary groups to meet the measured power consumption requirements of the four passengers.

[0102] The power consumption requirements may also be related to a limp mode duration power consumption requirement, where the controller 100 determines how much power is needed to keep the electric vehicle in limp mode (i.e., non-essential vehicle services such as air conditioning are powered off by the vehicle management system 125) for a certain amount of time, such as one hour. According to this embodiment, the controller 100 may measure electrical parameters of the vehicle's critical electrical services, such as the vehicle management system's power consumption requirements, to dynamically determine how much power is needed to maintain these critical electrical services for a specified duration.

[0103] Yet another power consumption requirement may be related to maintaining sufficient power for other safety and essential vehicle systems, including vehicle lighting, battery charging systems, and the like.

[0104] In an embodiment, an electric vehicle may include a high voltage battery power source (such as a 350V battery power source) for powering its electric motor, and an auxiliary 12V battery. In this embodiment, said power source 101 may take the form of an auxiliary 12V battery. In this regard, the controller 110 obtains various electrical parameter measurements to dynamically allocate sufficient battery cells 102 to the auxiliary group of the auxiliary 12V battery 101 to ensure that the auxiliary 12V battery 101 retains sufficient residual power to meet the associated power consumption requirements. Thus, even if the primary cells in the 12V battery are depleted, the auxiliary battery 101 will still have sufficient power to control (including powering the auxiliary for a certain duration or distance as may be applicable) various safety and essential functions of the vehicle (including door lock and opening mechanisms, the vehicle management system 125, the system controlling the high voltage battery, lighting, the battery charging system, power steering, etc.).

[0105] As alluded to above, the controller 111 takes various electrical parameter measurements (voltage, current draw, etc.) of these safety and essential systems to determine the power consumption requirements of the systems, including, in some cases, the power consumption requirements to operate the systems for a certain duration or distance.

[0106] In an embodiment, the controller 110 may obtain electrical parameter measurements to satisfy individual power consumption demands, however, in an embodiment, the controller 110 may obtain electrical parameter measurements for a combination of power consumption demands.

[0107] For example, during door opening, the controller 110 may measure the current draw electrical parameters of the associated door unlocking mechanism. Additionally, during cranking, the controller 111 may determine the power consumed by the starter motor 108 during cranking. Thus, the controller 110 may be programmed to ensure that sufficient cells 102 are assigned to the auxiliary group to meet the power consumption demands of both unlocking and cranking the door.

[0108] The foregoing description, for convenience of explanation, uses specific terminology to provide a thorough understanding of the invention. However, it will be apparent to one skilled in the art that specific details are not required to practice the present invention. Thus, the foregoing description of specific embodiments of the present invention has been presented for purposes of illustration and description. The foregoing description is not intended to be exhaustive or to limit the invention to the precise form disclosed, as many modifications and variations are possible in light of the above teachings. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, so that others skilled in the art can best utilize the invention and various modifications of the embodiments as suited to the particular use contemplated. It is intended that the following claims and their equivalents define the scope of the invention.

Claims

1. A vehicle power management system, comprising: a power source comprising a plurality of battery cells; and switching for controlling electrical connection of the battery cells, the system comprising: Measuring electrical parameters to determine power consumption requirements; dynamically allocating the battery cells to a primary group and an auxiliary group, the number of battery cells allocated to the auxiliary group being dependent on the power consumption requirement; During the power consumption requirement, the switching is controlled to electrically connect the battery cells assigned to the auxiliary group to supply power for the power consumption requirement. The system is configured as follows.

2. The system of claim 1 , wherein the power consumption demand is a cranking power consumption demand.

3. The system of claim 2 , further comprising an ammeter, the system configured to measure the cranking power demand using the ammeter during cranking.

4. The system of claim 2 , further comprising a voltmeter, the system configured to measure the cranking power demand using the voltmeter during cranking.

5. The system of claim 2 , wherein the system is configured to measure cranking power consumption over multiple crankings and calculate the cranking power consumption demand using a rolling average calculation.

6. The system of claim 1 , wherein the number of battery cells assigned to the auxiliary group is further dependent on a configuration setting.

7. The system of claims 2 and 6, wherein the configuration settings include at least one of an engine size and a fuel type.

8. The system of claim 1 , wherein the number of battery cells assigned to the auxiliary group is further dependent on an additional measured parameter.

9. The system of claims 2 and 8, wherein the further measured parameter is temperature.

10. The system of claim 1 , wherein the number of battery cells assigned to the auxiliary group is further dependent on a computational parameter.

11. The system of claims 2 and 10, wherein the calculation parameters include at least one of a battery life calculation parameter and a time since last cranking calculation parameter.

12. The system of claim 1 , wherein the system is configured to alternate an allocation of the battery cells between the primary group and the auxiliary group.

13. The system of claims 2 and 12, wherein the system is configured to alternate the allocation of the battery cells between the primary and auxiliary groups depending on the number of cranking events.

14. The system of claim 12 , wherein the system is configured to alternate an allocation of the battery cells between the primary group and the auxiliary group depending on a time period.

15. The system of claim 12 , wherein the system is configured to reserve at least one battery cell not assigned to the primary group.

16. The system of claim 1 , wherein during charging of the power source, the system is configured to control the switching to prioritize charging of battery cells assigned to the auxiliary group.

17. 17. The system of claim 16, wherein the system is configured to measure a state of charge of battery cells assigned to the supplemental group and prioritize charging of battery cells assigned to the supplemental group.

18. The system of claim 2 , wherein the system is configured to detect cranking and control the switching accordingly.

19. 20. The system of claim 18, wherein the system is configured to detect cranking by measuring a current draw above a threshold.

20. 3. The system of claim 2, wherein the system is manually configurable into a cranking mode, and the system is configured to control the switching to electrically connect battery cells assigned to the auxiliary group when the system is in the cranking mode.

21. 2. The system of claim 1, wherein the system is configured to measure a state of charge of battery cells assigned to the primary group to determine whether to control the switching to electrically connect battery cells assigned to the auxiliary group to provide power for the power consumption requirements.

22. 10. The system of claim 1, wherein the power source is a portable battery and the switching electrically connects the cells across terminals of the portable battery.

23. 23. The system of claims 2 and 22, wherein the portable battery further comprises a controller configured to measure the cranking power consumption demand and, during cranking, control the switching to electrically connect battery cells assigned to the auxiliary group to provide power for the cranking.

24. The system of claim 1 , wherein the power consumption requirement is a door mechanism power consumption requirement.

25. 2. The system of claim 1, wherein the power consumption requirement is a drivable range power consumption requirement, and the system is configured to measure electric motor electrical parameters while driving to determine a drivable range power consumption requirement for driving the vehicle a certain distance.

26. 26. The system of claim 25, wherein the system is further configured to adjust the number of battery cells assigned to the auxiliary group by measuring at least one of electrical circuit resistance, ambient temperature, drivetrain efficiency, vehicle mass, drag coefficient, rolling resistance, tire pressure, air conditioning system load, and number of passengers.

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