Battery management system and method

Abstract

A battery management system is provided. The battery management system includes a controller including at least one processor and at least one memory. The at least one memory includes instructions executed by the at least one processor to: receive, from a load sensor, load information about a load; receive, from a battery sensor, battery operating information; determine, based on the load information and the battery operating information, a number of battery modules required to power the load and operate each battery module at a preferred discharge rate or below the preferred discharge rate; select, based on the number of battery modules and the battery operating information, a set of battery modules included in a battery, each battery module included in the set of battery modules having a current depth of discharge within a preferred depth of discharge range; and instruct the battery to power the load using the set of battery modules.

Description

[0001] Cross-reference to related applications

[0002] This application is based on and claims priority to U.S. Provisional Patent Application No. 62 / 944,825, filed on December 6, 2019.

[0003] Explanation of federally funded research

[0004] not applicable. Background Technology

[0005] Material handling vehicles typically use rechargeable batteries (also known as secondary batteries) as their power source. Rechargeable batteries have a limited number of charge and discharge cycles before the end of their lifespan. To operate the batteries efficiently, a battery management system is implemented to monitor battery operation.

[0006] The battery management system may include sensors for deriving state-of-charge parameters. The sensors may also be used to derive state-of-health parameters. The battery management system may also include circuitry that prevents overcharging of the battery and operates the battery within predefined limits. Summary of the Invention

[0007] This disclosure generally relates to battery management systems for vehicles. More specifically, this disclosure relates to a battery management system optimized to extend battery life using battery-specific parameters such as cell chemistry, empirical data from state-of-charge fluctuations, and / or cell configuration.

[0008] In one aspect, this disclosure provides a battery management system. The battery management system includes: a battery sensor coupled to a battery, the battery including at least one battery module; a load sensor coupled to a load; an actuator coupled to the at least one battery module and the load; and a controller coupled to the battery sensor, the load sensor, and the actuator. The at least one battery module is associated with a preferred depth of discharge range and a preferred discharge rate. The controller includes at least one processor and at least one memory. The at least one memory includes instructions executed by the at least one processor to: receive load information about the load from the load sensor; receive battery operation information from the battery sensor; determine, based on the load information and the battery operation information, the number of battery modules required to power the load and operate each battery module at a preferred discharge rate or below the preferred discharge rate; select a group of battery modules to be included in the battery based on the number of battery modules and the battery operation information, each battery module in the group of batteries having a current depth of discharge within the preferred depth of discharge range; and instruct the battery to use the group of battery modules to power the load.

[0009] In this aspect, the disclosure provides a battery management system comprising: a battery sensor coupled to a battery, the battery comprising at least two battery modules; a load sensor coupled to a load; an actuator coupled to the at least two battery modules and the load; and a controller coupled to the battery sensor, the load sensor, and the actuator. The controller comprises at least one processor and at least one memory. The at least one memory comprises instructions executed by the at least one processor to: receive a battery profile, the battery profile comprising a plurality of operating parameter sets, each operating parameter set comprising a preferred discharge rate, a preferred depth of discharge range, and at least one environmental factor; receive load information about the load from the load sensor; receive battery operating information from the battery sensor; select a target operating parameter set included in the plurality of operating parameter sets based on the battery operating information; determine a number of battery modules required to power the load based on the load information, the battery operating information, and the target operating parameter set; select a set of battery modules included in the battery based on the number of battery modules and the battery operating information; and instruct the battery to power the load using the set of battery modules.

[0010] In this aspect, the disclosure provides a battery management method comprising: receiving load information about a load from a load sensor coupled to the load; receiving battery operating information from a battery sensor coupled to a battery, the battery comprising a plurality of battery modules; determining a number of battery modules required to power the load and operate each battery module included in the battery at or below a preferred discharge rate based on the load information and the battery operating information; selecting a set of battery modules included in the battery based on the number of battery modules and the battery operating information, each battery included in the set of batteries having a current depth of discharge within a preferred depth of discharge range; and instructing the battery to power the load using the set of battery modules.

[0011] The foregoing and other aspects and advantages of the disclosure will appear from the following description. In the description, reference is made to the accompanying drawings which form a part hereof, and in which are shown by way of illustration preferred configurations in accordance with the disclosure. Such configurations do not necessarily represent the full scope of the disclosure, however, and reference is therefore made to the claims and herein for interpreting the scope of the disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0012] The application will be better understood from the following detailed description when considered in connection with the following drawings, of which:

[0013] Figure 1 is an exemplary plot of various state of charge (SOC) curves.

[0014] Figure 2is an example block diagram of a battery management system of a material handling vehicle.

[0015] Figure 3 is a plot of load over time of a battery management system.

[0016] Figure 4 is an example of a process for managing a load coupled to a battery.

[0017] Figure 5 is an example of a process to charge a battery.

[0018] Corresponding reference numerals indicate corresponding parts throughout the several views. While the drawings represent embodiments of the disclosure, the drawings are not necessarily to scale and certain features can be exaggerated in order to better illustrate and explain the embodiments of the disclosure. DETAILED DESCRIPTION

[0019] Before any aspects of the disclosure are explained, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The disclosure is capable of other configurations or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. In this document, "including" "comprising" or "having," and variations thereof, mean encompassing the items listed thereafter and their equivalents as well as additional items. Unless specified or limited otherwise, the terms "mounted," "connected," "supported," and "coupled," and variations thereof, are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, "connected" and "coupled" are not restricted to physical or mechanical connections or couplings.

[0020] The following discussion is presented to enable a person skilled in the art to make and use aspects of the disclosure. Various modifications to the configurations shown will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other configurations and applications without departing from the aspects of the disclosure. Thus, the aspects of the disclosure are not intended to be limited to the configurations shown, but are to be accorded the widest scope consistent with the principles and features disclosed herein. The following detailed description is to be read with reference to the drawings, in which like elements in different drawings are identified with the same reference numerals. The drawings, which are not necessarily to scale, depict selected configurations and are not intended to limit the scope of the disclosure. Skilled artisans will appreciate the illustration provided herein is well as its attendant advantages in terms of providing a non-limiting example of the principles and features disclosed herein.

[0021] Generally, the disclosure provides systems and methods of managing battery health in a material handling vehicle.

[0022] Figure 1 Example graphs showing various state of charge (SOC) curves are shown. Each curve represents an SOC curve for a battery to determine life-extending and / or charge-extending operation parameters for that battery. Life-extending parameters can be parameters in which a battery can be operated in order to extend the useful life of the battery. The useful life of a battery can be related to how many charge / discharge cycles a battery can go through before the battery can be considered end-of-life for a particular application (e.g., 80% of initial capacity). Operating a battery in a manner that minimizes battery degradation can allow the battery to better retain capacity and, thus, operate for longer between charge cycles, which can improve the efficiency of the warehouse. Thus, operating a battery with life-extending parameters can also extend the charge life between charge cycles. Generally, batteries on a materials handling vehicle can differ in cell chemistry, state of charge swing, and / or cell construction. Battery cell chemistries can include lithium ion, lithium ion polymer, nickel metal hydride, nickel cadmium, lead acid, or any other type of cell chemistry suitable for powering a materials handling vehicle. Depending on the chemistry, the cell construction of a battery can include cylindrical cells, soft pack cells, or custom shapes such as cells with lithium ion polymer chemistry. Batteries can include any number of cells configured to produce a nominal voltage. All of these varying constituent and design factors can change the performance characteristics of a battery within a materials handling vehicle.

[0023] In order to determine a desired range of operation parameters and / or conditions of a battery within a materials handling vehicle that provide charge-extending and performance benefits (i.e., operation parameters / conditions that are least taxing on the life and / or battery charge consumption), a group of batteries with the same cell chemistry and construction can be subjected to individualized testing. Each battery can be subjected to a predetermined number of charge / discharge cycles with predetermined operation parameters for each battery. The parameters can include a charge rate (also referred to as a C-rate (e.g., 2C)), a discharge rate (e.g., 1C), a depth of discharge (DoD) operating window (e.g., 90-5%), an ambient or cell temperature, or other parameters that can affect the operation and / or state of health (SOH) of a battery. For accuracy, some of the batteries in the test can have repeated sets of operation parameters, i.e., ten sets of operation parameters can be repeated for three different batteries out of a total of thirty batteries.

[0024] The useful life of a battery can be related to SOH, which can be monitored by measuring how well the battery retains capacity in response to charge / discharge cycles. More specifically, the amount of charge that flows into or out of the battery can be compared to the SOC. SOH can be determined after each charge cycle and / or discharge cycle. Analysis can then be performed to determine the battery that has the best SOH or average SOH after each cycle in order to determine a combination of operating parameters of the battery that promotes extending the charge of the battery. For example, a battery can be determined to have a longer life (i.e., the number of charge cycles while still having the ability to retain useful charge) when used at a charge rate of 1C, a peak discharge rate of 2.5C, a window of available capacity of 80%-5%, and at a cell temperature of 25°C, but not at other operating parameter values. Some batteries can have different desired parameters in different environments, such as in different ambient temperatures. Multiple batteries used in testing that have a battery configuration (e.g., cell configuration, cell chemistry, number of cells, etc.) can be configured to function as a module of a larger battery. In other words, a larger battery has multiple modules that share configuration characteristics that can be used to operate the battery in a manner that extends the life of the battery, as will be explained below.

[0025] Figure 2 An example block diagram of a battery management system 200 of a materials handling vehicle 202 is shown. The battery management system 200 can be coupled to a load 220 and a battery 240. The battery management system 200 can also be coupled to a charger 260 in order to charge the battery 240 when applicable.

[0026] The load 220 can include any number of systems of the materials handling vehicle 202 that can require power from the battery 240. The systems can include a propulsion system, a fork system, a steering system, or any other system used to handle materials. The load 220 can require varying power / current from the battery 240 over time, which varies depending on the actions being performed by the vehicle. For example, if the materials handling vehicle 202 needs to propel itself forward while lifting a load of materials, the power / current demand will be higher than when the materials handling vehicle 202 is not moving and is not lifting a load of materials.

[0027] The battery 240 can be divided into any number of modules. In some embodiments, there is a first battery module 244, a second battery module 248, a third battery module 252, and a fourth battery module 256. Each module can have similar capacities, cell characteristics, and / or cell configurations. Each battery module can be individually coupled to the battery management system 200. While four battery modules are shown, it should be understood that the battery 240 can be divided into any number of modules.

[0028] The battery management system 200 may include a controller 204, a battery sensing module 208, and a power flow module 212 coupled to each other. The controller 204 may include a memory 204A and a processor 204B configured to execute instructions stored in the memory 204A. The controller may have a load management algorithm and a charging management algorithm stored in the instruction storage memory. These will be combined separately. Figure 4 and Figure 5 Load management algorithms and charging management algorithms are discussed. In some embodiments, controller 204 may have a human-machine interface (HMI) configured to receive input or commands from a human operator. In some embodiments, controller 204 may have a data interface 204C capable of connecting to an external computing device, network, or data storage medium via USB, Ethernet, Controller Area Network (CAN) bus, or other wired connections, or WiFi, Bluetooth, or other wireless connections.

[0029] Memory 204A may be coupled to processor 204B. In some embodiments, processor 204B may be any suitable hardware processor or combination of processors (such as a central processing unit (“CPU”), a graphics processing unit (“GPU”), an application-specific integrated circuit (ASIC) etc.) that can execute a program that may include the processes described below.

[0030] In some embodiments, memory 204A may include any suitable one or more storage devices that can be used to store instructions, values, etc., and can be used, for example, to perform the following combination. Figure 4 and Figure 5 The processes 400 and / or 500 are described. Memory 204A may include any suitable volatile memory, non-volatile memory, storage, or any suitable combination thereof. For example, memory 204A may include RAM, ROM, EEPROM, one or more flash memory, one or more hard disk drives, one or more solid-state drives, one or more optical drives, etc.

[0031] The battery sensing module 208 may include one or more sensors coupled to the load 220 and / or battery modules 244, 248, 252, 256. The sensors may be configured to measure parameters of the load 220, such as the current flowing from the battery management system 200 to the load 220. Additionally, the sensors may be configured to measure parameters such as the current flowing to or from one or more of the battery modules 244, 248, 252, 256 or the battery 240, the voltage of one or more of the batteries 240 or the battery modules 244, 248, 252, 256, the pressure of one or more of the battery modules 244, 248, 252, 256 or the battery 240, or any other parameters that may be used to determine the state of charge and / or state of health of one or more of the battery modules 244, 248, 252, 256 or the battery 240. In some embodiments, the battery sensing module 208 may include a data interface coupled to the battery, such as a USB interface or other transmission line capable of receiving data from a memory coupled to the battery. The battery sensing module may then receive data about the battery, such as model number, battery chemistry, battery cell configuration, battery capacity, serial number, or other relevant information about the battery. The battery sensing module 208 may include one or more temperature sensors coupled to battery modules 244, 248, 252, and 256 to sense the temperature of each battery module 244, 248, 252, and 256. The sensed temperature of each battery module 244, 248, 252, and 256 can be used to determine which battery module should be used to power a load, as will be described below.

[0032] Controller 204 can aggregate parameters measured from battery modules 244, 248, 252, and 256 to determine the state of charge and / or depth of discharge (DoD) of each individual battery module, and apply output via actuators to control the power flowing from battery modules 244, 248, 252, and 256. Controller 204 can also use the measured parameters to track battery module lifetime parameters, such as the total number of charge / discharge cycles and / or health status.

[0033] Power flow module 212 can control the power flow to and from battery 240, battery modules 244, 248, 252, 256, load 220, and / or charger 260. Power flow module 212 may include any number of passive components (such as resistors, capacitors, inductors, transformers, solenoids, or amplifiers), active elements (such as diodes, transistors, integrated circuits, power supplies, or transducers), voltage regulators, current regulators, chargers, bidirectional converters, fuses, actuators (such as switches), sensors, or other electrical components configured to control and / or regulate the power flow throughout the battery management system. Power flow module 212 may include multiple DC / DC converters. Each DC / DC converter may be coupled to a different individual battery module. Each DC / DC converter may also be coupled to a common electrical bus. The DC / DC converters can convert relatively low voltages (e.g., 12VDC) from the battery modules to relatively high voltages (such as 180VDC), which can be used to power material handling vehicles. The power flow module 212 may include any number of actuators coupled to the controller 204, charger 260, load 220, and / or battery 240. The controller 204 may control the state (i.e., on or off) of the actuators(s) to control the power flow between the battery 240, battery modules 244, 248, 252, 256, load 220, and / or charger 260.

[0034] refer to Figure 2 as well as Figure 3 A diagram illustrating a load 220 coupled to a battery management system 200 is shown. The load can be quantified by the required power or current magnitude, and the load can vary over time. The battery management system 200 can control the performance of a battery 240 in response to one or more parameters of the load 220 that vary over time. The battery 240 can be divided into any number of modules. As described above, in some embodiments, each module can be a battery. At various time points T1-T 10 The charging state or charge level of each module 244, 248, 252, and 256 is shown. Figure 3 In this context, the load 220 is quantified relative to the load capacity of a single battery module. Each module can be evaluated at a nominal voltage. Each module may have unit chemistry and / or unit construction shared with at least one other module. Each module may have multiple cells and / or volumes shared with at least one other module. In some embodiments, all modules 244, 248, 252, 256 have the same unit chemistry. In some embodiments, multiple batteries with any number of total modules may exist that the battery management system 200 can control and / or monitor.

[0035] The battery management system 200 may have a battery profile corresponding to the battery 240, which allows the battery management system 200 to supply power in a manner that extends the lifespan of the battery 240. The battery profile may include a desired set of operating parameters for the battery 240, such as charging rate, discharging rate, depth of discharge (DoD) operating window, and / or ambient or cell temperature. The battery profile may be stored in the memory of the controller 204. When the battery 240 operates with or within the desired operating parameters, the lifespan of the battery 240 can be extended. The battery profile may have multiple sets of desired operating parameters to account for different environmental factors. For example, for different ambient temperatures, the battery 240 may operate better with different charging rates, discharging rates, and / or DoD operating windows. At colder temperatures, the battery 240 may have a lower desired discharge rate than at warmer temperatures. Compared to a load with arbitrary current requirements at warmer temperatures, the battery management system 200 can use more modules to supply a load with the same arbitrary current requirements at colder temperatures.

[0036] The battery management system 200 can selectively determine which modules of the battery 240 will supply power to the load 220 in a predetermined manner to promote extended battery life and / or charge. The battery management system 200 can use the components described above to track parameters and control the power flow between the battery 240 and the load 220 and / or modules. As described above, each module may include a DoD window and discharge rate to promote extended life and / or charge. When the battery 240 is fully charged, all modules start at T1 with a DoD located at the upper end of the DoD window, and all modules are ready to supply power to the load 220. The battery management system 200 can supply current / power to the load 220 using various modules over time. The battery management system 200 can keep modules at or above a minimum charge or SOC level to keep the battery 240 able to support relatively high loads, which may require at least two modules. The minimum SOC charge level can be located inside or outside the DoD window.

[0037] When load 220 has no load power requirement (e.g., at T1), the battery management system 200 can prevent any module from supplying power to the load. At T1, all battery modules 244, 248, 252, and 246 are in a state of charge at a nominal discharge start level (e.g., fully charged). When load 220 has a relatively low power requirement (e.g., at T2), the battery management system 200 can determine that the power to the load is best supplied by a single module. At T2, load 220 increases to a level requiring engagement of a battery module. For example, the battery management system 200 can determine that load 220 will require a current approximately equal to the desired discharge rate of the module. The battery management system 200 can also determine which module has the minimum number of total discharge cycles and select that module to supply power to load 220 to balance the total usage of modules and thereby maximize the lifespan of battery 240. In some embodiments, the battery management system 200 can also determine which module has the minimum depth of discharge and / or the battery module temperature corresponding to the discharge rate closest to the current required by load 220 (i.e., the temperature sensed using a temperature sensor coupled to the battery module). At T2, the battery management system 200 selects the first module 244 to power the load 220. At T3 and T4, the load 220 continues to maintain approximately the same level as at T2, and the battery management system 200 may continue to allow the first module 244 to power the load 220 if the first module 244 remains within the desired DoD window. The state of charge of the first battery module 244 decreases at T2, T3, and T4. In some embodiments, if the charge level of the currently active module (i.e., the first module 244) is less than the charge levels of(a plurality of) other modules(a plurality of) a predetermined threshold level, the battery management system 200 may select a different module to power the load 220. This may allow for balancing module usage, helping to maximize the lifespan of the battery 240 and / or the time between charge cycles. In some embodiments, if the discharge rate, module temperature, module voltage, voltage level of cells within the module, time at discharge rate, time at charge rate, or cell balance state of the currently active module (i.e., the first module 244) differs from the discharge rate, module temperature, module voltage, voltage level of cells within the module, time at discharge rate, time at charge rate, or cell balance state of the other modules by a predetermined threshold level, the battery management system 200 can select different modules to power the load 220. This can also allow the use of balancing modules to help maximize the lifespan of the battery 240 and / or the time between charge cycles.

[0038] When load 220 has relatively high power requirements (such as at T5), battery management system 200 can determine that the power to the load is best supplied by three modules. Subsequently, the state of charge (DOC) of each of the three modules will decrease. For example, the load may be approximately three times the nominal load capacity of the battery modules. Battery management system 200 can then select three modules to power the load. At T5, battery management system 200 selects first module 244, second module 248, and third module 252 to power load 220. Battery management system 200 can select three modules by continuing to use the already active module(s) (i.e., first module 244) and selecting additional modules to power load 220. In some embodiments, battery management system 200 can select the three modules with the highest charge levels to power the load in order to balance module usage. In some embodiments, battery management system 200 can select as many battery modules as possible with charge levels within a desired DoD window to power load 220 in order to achieve maximum load distribution across battery 240 and minimize the load on each module. In some embodiments, the battery management system 200 may select modules based on real-time operating parameters (such as battery module temperature, voltage, DoD, etc.) and the maximum discharge rate of each module, minimizing the number of modules used to power the load. In some embodiments, the battery management system 200 may use multiple battery modules to power the load 220, which provide varying power / current levels based on the real-time operating parameters (temperature, voltage, DoD, etc.) of each battery module to meet the required total load.

[0039] When the load 220 is a relatively moderate value (e.g., at T6), the battery management system 200 can determine that the power to the load is best supplied by two modules. At T6, the load 220 decreases to a relatively low load level that would require both battery modules, and the state of charge of each of the two battery modules decreases. For example, the battery management system can determine that the load 220 will require approximately twice the current of the module's desired discharge rate, such as if the load 220 requires 1.8A and the module's desired discharge rate is 1.0A. Subsequently, the battery management system 200 can select two modules to power the load 220. At T6, the battery management system 200 selects the first module 244 and the second module 248 to power the load 220. The battery management system 200 can select the two modules by continuing to use the two longest-used active modules or the module with the lowest charge level. In some embodiments, the battery management system 200 can select the two modules with the highest charge levels to power the load in order to balance module usage. In some embodiments, the battery management system 200 can "rotate" between battery modules to reduce the continuous discharge current by pulsating the discharge current from the two selected battery modules before switching between them to output discharge current. This reduces the continuous discharge current from each battery module, which can prevent wear and tear on the battery modules.

[0040] When the load 220 is relatively low (e.g., at T7), the battery management system 200 can determine that the power to the load is best supplied by one module. At T7, the load can be reduced from T6. For example, the battery management system can determine that the load 220 will require a current approximately equal to the desired discharge rate of the module, such as if the load 220 requires 1.1A and the desired discharge rate of the module is 1.0A. Subsequently, the battery management system 200 can select a module to power the load. At T7, the battery management system 200 selects the first module 244 to power the load 220. The battery management system 200 can select a module by continuing to use the longest-used active module or the module with the lowest charge level. In some embodiments, the battery management system 200 can select the module with the highest charge level to power the load in order to balance module usage.

[0041] When one or more modules currently powering the load reach the bottom of the DoD window (e.g., at T8), the battery management system 200 can select one or more different modules to power the load. The load 220 increases from T8, and the state of charge of the first battery module 244 reaches a "low" threshold, indicating that the first battery module 244 cannot provide more charge. Subsequently, two different battery modules are engaged to provide additional power. At T8, the battery management system 200 can determine that the power to the load is best supplied by two modules. For example, the battery management system can determine that the load 220 will require approximately twice the current of the module's expected discharge rate, such as if the load 220 requires 2.4A and the module's expected discharge rate is 1.0A. The battery management system 200 can then select two modules with charge levels within the DoD window to power the load. At T8, the battery management system 200 selects to power the load 220 using the second module 248 and the third module 252. The power management system 200 can select two modules by continuing to use either the two longest-used active modules or the module with the lowest charge level. In some embodiments, the battery management system 200 may select the two modules with the highest charge levels to power the load in order to balance the use of the modules.

[0042] At T9, load 220 can remain approximately the same as at T8, and if the second module 248 and the third module 252 remain within the desired DoD window, the battery management system 200 can continue to allow the second module 248 and the third module 252 to power load 220. The state of charge of the second module 248 and the third module 252 is reduced. When load 220 has zero power requirements (such as at T...), 10 When (at a certain point), the battery management system 200 can prevent any module from supplying power to the load. In T 10 At this point, the charging state of the second module 248 reaches a "low" threshold, indicating that the second module 248 cannot provide more charge. In some embodiments, the battery management system 200 can prevent any battery module from supplying current at a rate greater than a predetermined discharge rate, which may be equal to the desired discharge rate.

[0043] Now for reference Figure 2 as well as Figure 4 An example of a process 400 for managing a load 220 coupled to a battery 240 is shown. In some embodiments, process 400 may be implemented as instructions on at least one memory of a computing device such as a controller 204 and executed by at least one processor coupled to the memory.

[0044] At 404, process 400 may receive battery model data. The battery model data may include model number, serial number, battery chemistry, battery cell configuration, battery capacity, or other relevant information about battery 240. In some embodiments, process 400 may receive the battery model data from a memory coupled to battery 240, where the battery model data is stored. In some embodiments, process 400 may receive the battery model data from a human-machine interface (HMI) of controller 204, the HMI being configured to receive input or commands from a human operator. In some embodiments, process 400 may receive the battery model data from a data interface of controller 204, which is capable of connecting to an external computing device or network via USB, Ethernet, or other wired connections, or WiFi, Bluetooth, or other wireless connections. Process 400 may then proceed to 408.

[0045] At 408, process 400 may select a battery profile based on battery model data. The battery profile may include battery-specific data, such as the battery model corresponding to battery 240 and / or battery modules 244, 248, 252, 256 of battery 240, battery chemistry, battery cell construction, and / or battery capacity. The battery profile may also include one or more sets of operating parameters associated with battery 240. Each set of operating parameters may include values ​​for a plurality of parameters, such as charging rate, discharging rate, depth of discharge (DoD) operating window, and / or ambient or cell temperature. Each of the parameters included in these plurality of parameters may be referred to as a “preferred” parameter, such as extending the lifespan of battery 240 when battery 240 operates at or within the desired operating parameters. The battery profile may have multiple desired sets of operating parameters to account for different environmental factors. Process 400 may have a set of predetermined battery profiles corresponding to the battery model, battery chemistry, battery cell construction, and / or battery capacity parameters of battery 240 and / or battery modules 244, 248, 252, 256 of battery 240. The process may select a battery profile from the set of battery profiles based on which battery profile most closely matches the battery model. For example, process 400 may determine that a target battery profile in the set of battery profiles has a battery model that matches the current battery 240 and select that target battery profile. In some embodiments, the battery profile may be implemented as one or more equations corresponding to the battery (and battery module) based on battery model data. For example, process 400 may select one or more equations corresponding to a battery having the model, battery chemistry, battery cell construction, and / or battery capacity included in the battery model data. In some embodiments, the battery profile may be implemented using machine learning techniques such as artificial neural networks. The artificial neural network can be trained using operating data under various operating conditions (i.e., various temperatures, supplied currents, etc.). Once trained, the artificial neural network can provide an output state of command in response to newly encountered input operating conditions. Process 400 can then proceed to 412.

[0046] At 412, process 400 can sense load information about load 220. In some embodiments, process 400 can receive load information from one or more sensors coupled to load 220. In some embodiments, load information may include the current flowing to load 220, the impedance of load 220, or any other parameter that can be used to determine the power requirement of load 220. Sensors may be included in battery sensing module 208. Process 400 may directly use the received load information to determine the power requirement or current requirement of load 220. Alternatively, process 400 may calculate the power requirement or current requirement of load 220 based on the load information to determine the power requirement or current requirement of load 220. In some embodiments, the current requirement may be formatted as an ampere requirement. In some embodiments, load 220 may transmit the power requirement or current requirement to process 400. Subsequently, load 220 is required to keep its power or current consumption within an allowable load level. Process 400 may then proceed to 416.

[0047] At 416, process 400 may receive battery operation information regarding battery 240. The battery operation information may include: current flowing to or from one or more of battery modules 244, 248, 252, 256 or battery 240; voltage of one or more batteries 240 or battery modules 244, 248, 252, 256; pressure of one or more of battery modules 244, 248, 252, 256 or battery 240; or any other parameter that can be used to determine the state of charge of one or more of battery modules 244, 248, 252, 256 and / or battery 240. Process 400 may use the battery operation information from multiple points in time, using methods known in the art, to calculate the state of charge of battery 240 and / or individual modules 244, 248, 252, 256. The battery operation information may also include environmental information about the battery 240, such as one or more of modules 244, 248, 252, and 256 and / or the temperature of the battery 240. Process 400 may then proceed to 420.

[0048] At 420, process 400 can determine whether to supply power to load 220. The process can determine whether to supply power to load 220 based on battery operating information. If battery 240 is determined to be depleted, such as if all modules 244, 248, 252, and 256 of battery 240 are depleted, or all battery modules 244, 248, 252, and 256 have a charge level at the bottom of the desired DoD window, then process 400 can determine not to supply power to load 220. If at least one battery module has a charge level above the bottom of the desired DoD window, or if at least one battery module is not depleted, then process 400 can determine to supply power to load 220. If process 400 determines not to supply power to load 220, then the process can then terminate. If process 400 determines to supply power to load 220, then process 400 can proceed to 424.

[0049] At 424, process 400 can supply power to load 220 based on load information, battery operation information, and / or battery profile. In some embodiments, process 400 can select a target set of operating parameters included in one or more sets of operating parameters based on environmental information included in the battery operation information. For example, process 400 can select an operating parameter set as the target set that has an environmental or cell temperature closest to the operating temperature of the battery included in the battery information. Subsequently, process 400 can operate battery modules 244, 248, 252, and 256 based on the target set of operating parameters. Using multiple sets of operating parameters allows process 400 to supply power to load 220 using the set of operating parameters best suited to the environmental and / or operating conditions of the battery. For example, process 400 can select a first set of operating parameters included in multiple sets of operating parameters as the target set of operating parameters. The first set of operating parameters may include a first preferred discharge rate, a first preferred depth of discharge range, and a first environmental factor (e.g., a first preferred battery temperature). Process 400 may select a first set of operating parameters instead of a second set that includes a second preferred discharge rate, a second preferred depth of discharge range, and a second environmental factor (e.g., a second preferred battery temperature) because the first environmental factor is closer to battery operating information than the second environmental factor. For example, the first preferred battery temperature may be closer to the actual battery operating temperature than the second preferred battery temperature, and operating battery 240 based on the first preferred battery temperature may extend battery life. Some parameter values ​​may differ between the first and second sets of operating parameters. For example, the first preferred battery temperature may be lower than the second preferred battery temperature, and the first preferred discharge rate may be lower than the second preferred discharge rate. In some embodiments, the first environmental factor may be a first preferred battery temperature range, and the second environmental factor may be a second preferred battery temperature range. The first preferred battery temperature range may include typical temperatures found in warehouses and / or other storage facilities. For example, a first preferred battery temperature range may include 60-100℉, 60-80℉, 60-75℉, 70-100℉, 80-100℉, 65-95℉, 70-90℉, and / or other sub-ranges between 60-100℉. In some embodiments, a second preferred battery temperature range may include 60-100℉, 60-80℉, 60-75℉, 70-100℉, 80-100℉, 65-95℉, 70-90℉, and / or other sub-ranges between 60-100℉. In some embodiments, a second preferred battery temperature range may include temperatures outside of 60-100℉. For example, a second preferred battery temperature range may include 55-100℉, 55-80℉, 40-65℉, 70-110℉, 80-120℉, 80-110℉, 70-105℉, etc. In some embodiments, process 400 may power load 220 differently based on battery operating temperature.For example, if process 400 selects a first set of parameters because the battery operating temperature falls within a first preferred battery temperature range and not within a second preferred battery temperature range, then process 400 can power the load with a different number of battery modules (e.g., because the preferred discharge rate included in the first set of parameters is different from the allowable discharge rate included in the second set of parameters).

[0050] Process 400 can determine which portion of battery modules 244, 248, 252, and 256 will be used to power load 220. First, process 400 can calculate the most desired number of battery modules 244, 248, 252, and 256. This most desired number of battery modules 244, 248, 252, and 256 can be the number of battery modules 244, 248, 252, and 256 that will be able to power load 220 and maintain a discharge rate closest to or lower than the maximum discharge rate of battery modules 244, 248, 252, and 256 (as stored in the battery profile). The desired discharge rate and / or maximum discharge rate can be less than the maximum permissible discharge rate of battery 240 and / or battery modules 244, 248, 252, and 256 (e.g., less than the manufacturer's maximum rated discharge rate). Process 400 can also select the desired discharge rate at that temperature based on the battery profile, using battery environmental information such as the temperature of battery 240. Subsequently, process 400 can determine the most desired portion of battery modules 244, 248, 252, and 256 to power load 220. For example, process 400 can determine that the most desired number of battery modules 244, 248, 252, and 256 is three, and select three battery modules 244, 248, 252, and 256 with charge levels within the desired DoD window in the battery profile. Subsequently, additional conditions can be used to select battery modules 244, 248, 252, and 256, such as selecting the three lowest charge levels within a desired DoD window, selecting the three highest charge levels within a desired DoD window, selecting as many battery modules 244, 248, 252, and 256 as possible that are already powering load 220, and / or any other conditions that help maximize the lifespan or time between charging cycles of battery 240 and / or battery modules 244, 248, 252, and 256. Once a battery module is selected, process 400 can actuate an actuator, such as a switch coupled to battery modules 244, 248, 252, and 256 and load 220, to power load 220 using the selected battery module. The actuator may be included in power flow module 212. Process 400 can then proceed to 412. Process 400 can perform steps 412-424 multiple times per second to adapt to dynamic load requirements without introducing perceptible delays to the operator.

[0051] Now for reference Figure 2 as well as Figure 5 An example of a process 500 for charging battery 240 is shown. Process 500 can be executed when battery management system 200 is coupled to charger 260. Process 500 can also be executed when a material handling vehicle is performing regenerative charging (such as when the elevator of the material handling vehicle is lowering or when the material handling vehicle is braking). Process 500 can be implemented as instructions on the memory of a computing device such as controller 204.

[0052] At 504, process 500 may receive battery model data. Battery model data may include model number, serial number, battery chemistry, battery cell configuration, battery capacity, or other relevant information about battery 240. In some examples, process 500 may receive battery model data from a memory coupled to battery 240, where the battery model data is stored. In some embodiments, process 500 may receive battery model data from a human-machine interface (HMI) of controller 204, the HMI being configured to receive input or commands from a human operator. In some embodiments, process 500 may receive battery model data from a data interface of controller 204, which is capable of connecting to an external computing device or network via USB, Ethernet, or other wired connections, or WiFi, Bluetooth, or other wireless connections. Process 500 may then proceed to 508.

[0053] At point 508, process 500 can select a battery profile based on battery model data. The battery profile may include battery-specific data, such as the battery model corresponding to battery 240, battery chemistry, battery cell configuration, and / or battery capacity. The battery profile may also include a desired set of operating parameters for battery 240, such as charging rate, discharging rate, depth of discharge (DoD) operating window, and / or ambient or cell temperature. Operating battery 240 at or within the desired operating parameters can extend its lifespan. The battery profile may have multiple desired sets of operating parameters to account for different environmental factors. Process 500 may have a predetermined set of battery profiles corresponding to various battery models, battery chemistry, battery cell configuration, and / or battery capacity parameters for battery 240. The process can select a battery profile from a set of battery profiles based on which battery profile most closely matches the battery model. For example, process 500 may determine that a target battery profile in a set of battery profiles has a battery model corresponding to the current battery 240 and select that target battery profile. In some embodiments, the battery profile can be implemented as one or more equations corresponding to the battery (and battery module) based on battery model data. For example, process 500 may select one or more equations corresponding to a battery having a model, battery chemistry, battery cell configuration, and / or battery capacity included in the battery model data. In some embodiments, the battery profile can be implemented using machine learning techniques such as artificial neural networks. The artificial neural network can be trained using operating data under various operating conditions (i.e., various temperatures, supplied currents, etc.). Once trained, the artificial neural network can provide an output state of a command in response to newly encountered input operating conditions. Process 500 may then proceed to 512.

[0054] At 512, process 500 may receive battery operation information regarding battery 240. The battery operation information may include: current flowing to or from one or more of battery modules 244, 248, 252, 256 or battery 240; voltage of one or more batteries 240 or battery modules 244, 248, 252, 256; pressure of one or more of battery modules 244, 248, 252, 256 or battery 240; or any other parameter that can be used to determine the state of charge of one or more of battery modules 244, 248, 252, 256 and / or battery 240. Process 500 may use the battery operation information from multiple points in time, using methods known in the art, to calculate the state of charge of battery 240 and / or individual modules. The battery operation information may also include environmental information about battery 240, such as the temperature of one or more of modules 244, 248, 252, 256 and / or battery 240. Process 500 can then proceed to 516.

[0055] At 516, process 500 may determine whether to supply power to one or more modules 244, 248, 252, 256 of battery 240. If process 500 determines that all battery modules 244, 248, 252, 256 have a charge level at the upper limit of the desired DoD window in the battery profile, then process 500 may terminate. If process 500 determines that at least one battery module has a charge level less than the upper limit of the DoD window, then process 500 may proceed to 520.

[0056] At 520, process 500 can power battery modules 244, 248, 252, and 256 based on battery operation information and / or battery profiles. Process 500 can determine, based on the battery information, which battery modules have charge levels below the desired DoD operating window. Subsequently, process 500 can determine the desired charging rate for battery modules 244, 248, 252, and 256 based on the battery profiles. Process 500 can also select the desired charging rate at that temperature based on the battery profiles, using battery environmental information such as the temperature of battery 240. Subsequently, process 500 can drive actuators to power the selected battery modules at the desired charging rate. In some embodiments, battery modules 244, 248, 252, 256 may be coupled to a circuitry located, for example, in battery 240 or power flow module 212, and configured to provide a charging rate at or near a desired charging rate, and simply drive one or more actuators to supply power from the circuitry to one or more battery modules 244, 248, 252, 256 having a charge level determined to be below a desired DoD operating window. The actuators may be included in power flow module 212. Process 500 may then proceed to 512.

[0057] In some embodiments, any suitable computer-readable medium may be used to store instructions for performing the functions and / or processes described herein. For example, in some embodiments, the computer-readable medium may be transient or non-transient. For example, a non-transient computer-readable medium may include media such as magnetic media (e.g., hard disks, floppy disks, etc.), optical media (e.g., compressed discs, digital video discs, Blu-ray discs, etc.), semiconductor media (e.g., RAM, flash memory, electrically programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), etc.), any suitable medium that is not transient during transmission or does not have any persistent appearance, and / or any suitable tangible medium. As another example, a transient computer-readable medium may be included on a network, in wires, conductors, optical fibers, circuits, or in any suitable medium that is transient during transmission and does not have any persistent appearance, and / or any suitable intangible medium.

[0058] It should be noted that the terminology used herein may cover hardware, software, firmware, or any appropriate combination thereof.

[0059] It should be understood that Figure 4 or Figure 5 The above steps of the process can be performed or carried out in any order or sequence, not limited to the order and sequence shown and described in the figure. Moreover, they can be performed or carried out substantially simultaneously or in parallel where appropriate. Figure 4 or Figure 5 Some of the steps mentioned above are used to reduce waiting and processing time.

[0060] By using the aspects of this disclosure, the battery management system can maximize battery life.

[0061] In this specification, embodiments have been described in a manner that enables a clear and concise description; however, it is intended and will be understood that embodiments may be combined or separated in different ways without departing from the invention. For example, it should be understood that all preferred features described herein are applicable to all aspects of the invention described herein.

[0062] Therefore, while the invention includes what has been described in conjunction with specific embodiments and examples, the invention is not necessarily limited thereto, and many other embodiments, examples, uses, modifications, and deviations from said embodiments, examples, and uses are intended to be covered by the appended claims. The full disclosure of each patent and publication cited herein is incorporated by reference, just as each such patent or publication is individually incorporated by reference.

[0063] The various features and advantages of the invention are set forth in the appended claims.

Claims

1. A battery management system comprising: a battery sensor coupled to a battery comprising at least one battery module, the at least one battery module associated with a preferred depth of discharge range and a preferred rate of discharge; a load sensor coupled to a load; an actuator coupled to the at least one battery module and the load; and a controller coupled to the battery sensor, the load sensor, and the actuator, the controller comprising at least one processor and at least one memory comprising instructions executed by the at least one processor to: receive load information about the load from the load sensor; receive battery operating information from the battery sensor; determine a number of battery modules required to power the load and operate each battery module at or below the preferred rate of discharge based on the load information and the battery operating information; select a set of battery modules included in the battery based on the number of battery modules and the battery operating information, each battery module included in the set of battery modules having a current depth of discharge within the preferred depth of discharge range; and instruct the battery to power the load using the set of battery modules. the battery comprises at least two battery modules, and wherein the number of battery modules comprises a first battery module and a second battery module, the first battery module and the second battery module included in the battery.

2. The battery management system of claim 1, wherein, the battery is a lithium-ion battery.

3. The battery management system of claim 1, wherein, a minimum depth of discharge of the preferred depth of discharge range is greater than a predetermined minimum state of charge associated with the at least one battery module.

4. The battery management system of claim 1, wherein, the preferred rate of discharge is less than a maximum allowable rate of discharge associated with the at least one battery module.

5. The battery management system of claim 1, wherein, the preferred depth of discharge range and the maximum allowable rate of discharge are predetermined based on testing.

6. The battery management system of claim 5, wherein, the testing comprises operating a plurality of batteries at a plurality of predetermined depth of discharge ranges and a plurality of predetermined maximum allowable rates of discharge.

7. The battery management system of claim 6, wherein, the at least one processor further executes the instructions to:

8. The battery management system of claim 1, wherein, receive a battery profile comprising a plurality of sets of operating parameters, each set of operating parameters comprising: a preferred rate of discharge, a preferred depth of discharge range, and at least one environmental factor.

9. The battery management system of claim 8, wherein: a first set of operating parameters included in the plurality of sets of operating parameters comprises: a first rate of discharge, a first preferred depth of discharge range, and a first environmental factor, a second set of operating parameters included in the plurality of sets of operating parameters comprises: a second rate of discharge, a second preferred depth of discharge range, and a second environmental factor, and at least one of: the first rate of discharge is different than the second rate of discharge, the first preferred depth of discharge range is different than the second preferred depth of discharge range, or the first environmental factor is different than the second environmental factor. ​ 10. The battery management system of claim 9, wherein, The battery operating information includes a battery operating temperature, and wherein the first environmental factor is a first preferred battery temperature range and the second environmental factor is a second preferred battery temperature range, the first preferred battery temperature range includes the battery operating temperature, and the second preferred battery temperature range does not include the battery operating temperature.

11. A battery management system, the battery management system comprising: a battery sensor coupled to a battery comprising at least two battery modules; a load sensor coupled to a load; an actuator coupled to the at least two battery modules and the load; and a controller coupled to the battery sensor, the load sensor, and the actuator, the controller comprising at least one processor and at least one memory including instructions executed by the at least one processor to: receive a battery profile, the battery profile comprising a plurality of operating parameter sets, each operating parameter set comprising: a preferred discharge rate, a preferred depth of discharge range, and at least one environmental factor; receive load information about the load from the load sensor; receive battery operating information from the battery sensor; select a target operating parameter set included in the plurality of operating parameter sets based on the battery operating information; determine a number of battery modules required to power the load based on the load information, the battery operating information, and the target operating parameter set; select a set of battery modules included in the battery based on the number of battery modules and the battery operating information; and instruct the battery to power the load using the set of battery modules.

12. The battery management system of claim 11, wherein, The battery operating information includes a battery operating temperature, and the at least one environmental factor includes a preferred battery temperature, and wherein the at least one processor further executes the instructions to: determine that the target operating parameter set includes a preferred battery temperature closer to the battery operating temperature than all other operating parameter sets included in the plurality of operating parameter sets.

13. The battery management system of claim 12, wherein, The load information includes an amp requirement, and wherein the at least one processor further executes the instructions to: determine the number of battery modules required to simultaneously satisfy the amp requirement and discharge each battery module included in the set of battery modules at an operating discharge rate close to the preferred discharge rate.

14. The battery management system of claim 11, wherein: a first operating parameter set included in the plurality of operating parameter sets, the first operating parameter set comprising: a first discharge rate, a first preferred depth of discharge range, and a first environmental factor, a second operating parameter set included in the plurality of operating parameter sets, the second operating parameter set comprising: a second discharge rate, a second preferred depth of discharge range, and a second environmental factor, and at least one of: the first discharge rate is different than the second discharge rate, the first preferred depth of discharge range is different than the second preferred depth of discharge range, or the first environmental factor is different than the second environmental factor.

15. The battery management system of claim 14, wherein, The battery operating information includes a battery operating temperature, and wherein the first environmental factor is a first preferred battery temperature range and the second environmental factor is a second preferred battery temperature range, the first preferred battery temperature range includes the battery operating temperature, and the second preferred battery temperature range does not include the battery operating temperature.

16. A battery management method comprising: receiving load information about a load from a load sensor coupled to the load; receiving battery operating information from a battery sensor coupled to a battery, the battery including a plurality of battery modules; determining, based on the load information and the battery operating information, a number of battery modules required to power the load and operate each battery module included in the battery at a preferred discharge rate or below the preferred discharge rate; selecting, based on the number of battery modules and the battery operating information, a set of battery modules included in the battery, each battery module included in the set of battery modules having a current state of charge within a preferred state of charge range; and directing the battery to power the load using the set of battery modules.

17. The method of claim 16, wherein, The battery is a lithium-ion battery, the battery includes at least two battery modules, and wherein the number of battery modules includes a first battery module and a second battery module, the first battery module and the second battery module being included in the battery.

18. The method of claim 16, further comprising: receiving a battery profile, the battery profile including a plurality of sets of operating parameters.

19. The method of claim 18, wherein a first set of operating parameters included in the plurality of sets of operating parameters includes: a first discharge rate, a first preferred state of charge range, and a first environmental factor, a second set of operating parameters included in the plurality of sets of operating parameters includes: a second discharge rate, a second preferred state of charge range, and a second environmental factor, and at least one of the following: the first discharge rate is different than the second discharge rate, the first preferred state of charge range is different than the second preferred state of charge range, or the first environmental factor is different than the second environmental factor.

20. The method of claim 19, wherein, The battery operating information includes a battery operating temperature, and wherein the first environmental factor is a first preferred battery temperature range and the second environmental factor is a second preferred battery temperature range, the first preferred battery temperature range includes the battery operating temperature, and the second preferred battery temperature range does not include the battery operating temperature.

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