System and method for controlling charging of energy storage system including plurality of battery packs

Abstract

The invention relates to a system and a method for controlling charging of an energy storage system comprising a plurality of battery packs, in particular to a computer system (100) comprising processing circuitry (102) configured to: determine (200) a state of charge (201), SoC, of each of a plurality of battery packs (150a to 150c) in an energy storage system (104) of a vehicle; determining (202) a temperature (203) of each of the plurality of battery packs; determining (204) an internal resistance (205) of each of the plurality of battery packs; setting (206) an initial target SoC (207) for the plurality of battery packs, each battery pack having the same initial target SoC; estimating (208) a final temperature (209) of each battery pack from a predetermined temperature model of the battery packs using the temperatures and the internal resistances of the respective battery packs to obtain the initial target SoC; determining (210) that the estimated final temperature of the battery pack exceeds a threshold temperature (211); and setting (212) a target SoC (213) for a decrease in which an estimate of the battery pack exceeds the threshold temperature.

Description

Technical Field

[0001] The present disclosure generally relates to charging of energy storage systems. In particular aspects, the present disclosure relates to a system and method for controlling the charging of an energy storage system including a plurality of battery packs. The present disclosure may be applied to heavy vehicles such as trucks, buses, and construction equipment, among other vehicle types. Although the present disclosure may be described with respect to a particular vehicle, the present disclosure is not limited to any particular vehicle. Background Art

[0002] In electric and hybrid vehicles that include energy storage systems with multiple battery packs, different battery packs may age differently, depending on both the manufacturing differences between the individual battery packs and how the battery packs are charged. In some cases, damage to a single battery pack in an energy storage system may require replacement or repair of the entire battery, resulting in undesirable downtime for the vehicle. Therefore, it is very important to find a favorable charging scheme to improve battery life. Summary of the invention

[0003] According to a first aspect of the present disclosure, a computer system is provided, which includes a processing circuit system configured to: determine the state of charge (SoC) of each of a plurality of battery packs in an energy storage system of a vehicle; determine the temperature of each of the plurality of battery packs; determine the internal resistance of each of the plurality of battery packs; set an initial target SoC for the plurality of battery packs, each battery pack having the same initial target SoC; estimate the final temperature of each battery pack from a predetermined temperature model of the battery pack using the temperature and internal resistance of the corresponding battery pack to obtain an initial target SoC; determine that the estimated final temperature of the battery pack exceeds a threshold temperature; and reduce the target SoC of the battery pack that is estimated to exceed the threshold temperature.

[0004] A first aspect of the present disclosure may seek to avoid overheating and excessive wear of a battery when charging a battery comprising a plurality of battery packs. Technical benefits may include: equalization of battery pack aging in an energy storage system comprising a plurality of battery packs, which may both improve the service life of the battery and reduce the risk of overheating during charging.

[0005] Optionally, in some examples, including in at least one preferred example, the processing circuit system is further configured to: receive an available charger capacity for charging the energy storage system; and set an initial target SoC for the plurality of battery packs based on the available charger capacity. Technical benefits may include: the target SoC can be adapted based on the properties of the charger. For example, a charger in the form of an external charging station may have limitations that limit the possible SoCs of the energy storage system. Therefore, knowing the properties and limitations of the charger, a more accurate initial target SoC can be set.

[0006] Optionally, in some examples, including in at least one preferred example, the received available charger capacity is at least one of available charging time, maximum charging power, maximum charging current, and total charging energy. Technical benefits may include: if the charger has limitations in terms of charging time, maximum charging power, maximum charging current, and total charging energy, an initial target SoC may be set so that the charger can charge the energy storage system to the set initial SoC.

[0007] Optionally, in some examples, including in at least one preferred example, the processing circuit system is further configured to: during charging, when a reduced target SoC is reached, disconnect the battery pack with the reduced target SoC from the energy storage system; and during operation of the vehicle, determine that at least one other battery pack has a SoC equal to the reduced target SoC and reconnect the battery pack with the reduced target SoC. Technical benefits may include: battery packs that have a reduced target SoC and are therefore charged to a lower SoC than other battery packs are not used until the other battery packs are at the same SoC, which in turn equalizes the aging and health state SoH of different battery packs.

[0008] Optionally, in some examples, including in at least one preferred example, the processing circuit system is further configured to: determine the cooling properties of the energy storage cooling system; and estimate the final temperature of the battery pack based on the cooling properties of the energy storage system. Technical benefits may include: the expected final temperature of the battery pack during charging takes into account not only the properties of the battery itself, but also the properties of the cooling system. For example, the cooling system may be operating at a reduced capacity, in which case the temperature of the battery pack when it reaches a certain SoC may be higher than expected. By taking into account the properties of the cooling system, a more accurate target SoC can be set from the beginning of the charging procedure.

[0009] Optionally, in some examples, including at least one preferred example, the processing circuit system is further configured to reduce the target SoCs of the plurality of battery packs estimated to exceed the corresponding predetermined threshold temperature to the target SoCs whose final temperature of the battery packs does not exceed the predetermined threshold temperature according to the predetermined temperature model. Technical benefits may include: when it can be determined whether more than one battery pack is estimated to exceed the threshold temperature, all battery packs that may exceed the threshold temperature may have a reduced target SoC.

[0010] Optionally, in some examples, including at least one preferred example, the processing circuit system is further configured to: determine a threshold temperature of the battery pack based on an expected decrease in the health state of the battery pack with temperature. Technical benefits may include: battery packs with lower health states will experience lower temperatures to avoid unnecessary damage to the battery pack.

[0011] Optionally, in some examples, including at least one preferred example, the processing circuit system is further configured to: estimate the maximum temperature rise rate of each battery pack to reach an initial target SoC from a predetermined temperature model of the battery pack using the temperature and internal resistance of the corresponding battery pack; and determine that the maximum temperature rise rate of the battery pack exceeds a threshold temperature rise rate; and according to the predetermined temperature model, reduce the target SoC of the battery pack estimated to exceed the threshold temperature rise rate to the target SoC of the battery pack that does not exceed the threshold temperature rise rate. Technical benefits may include: Faulty or degraded battery packs can be detected by monitoring the temperature rise rate, in which case temperature peaks can be prevented by reducing the target SoC even if the final temperature is not expected to exceed the threshold temperature. Therefore, monitoring the temperature rise rate provides an additional method to ensure that the battery pack is not damaged or unnecessarily degraded during charging.

[0012] Optionally, in some examples, including at least one preferred example, the processing circuit system is further configured to: in response to a lowered target SoC of the battery pack, control the charging circuit system to charge the battery pack to the lowered target SoC. Technical benefits may include: the processing circuit system of the vehicle can communicate directly with the charging circuit system, which can be arranged inside the vehicle, or arranged outside the charger or charging station.

[0013] According to a second aspect of the present disclosure, a computer-implemented method is provided, which includes: determining the state of charge (SoC) of each of a plurality of battery packs in an energy storage system of a vehicle through a processing circuit system of a computer system; determining the temperature of each of the plurality of battery packs; determining the internal resistance of each of the plurality of battery packs; setting an initial target SoC for the plurality of battery packs, each battery pack having the same initial target SoC; using the temperature and internal resistance of the corresponding battery pack, estimating the final temperature of each battery pack from a predetermined temperature model of the battery pack to obtain an initial target SoC; determining that the estimated final temperature of the battery pack exceeds a threshold temperature; and lowering the target SoC of the battery pack that is estimated to exceed the threshold temperature.

[0014] A second aspect of the present disclosure may seek to avoid overheating and excessive wear of the battery when charging a battery comprising multiple battery packs. Technical benefits may include: equalization of battery pack aging in an energy storage system comprising multiple battery packs, which can both improve the service life of the battery and reduce the risk of overheating during charging.

[0015] Optionally, in some examples, including in at least one preferred example, the method further comprises: receiving an available charger capacity for charging the energy storage system; and setting an initial target SoC for the plurality of battery packs based on the available charger capacity.

[0016] Optionally, in some examples, including in at least one preferred example, the received available charger capacity is at least one of available charging time, maximum charging power, maximum charging current, and total charging energy.

[0017] Optionally, in some examples, including in at least one preferred example, the method further includes, by the processing circuit system: during charging, when a lowered target SoC is reached, disconnecting the battery pack having a lowered target SoC from the energy storage system; and during operation of the vehicle, reconnecting the battery pack having a lowered target SoC when at least one other battery pack has a SoC equal to the lowered target SoC.

[0018] Optionally, in some examples, including in at least one preferred example, the method further comprises, by the processing circuit system: receiving cooling properties of the energy storage cooling system; and estimating a final temperature of the battery pack based on the cooling properties of the energy storage system.

[0019] Optionally, in some examples, including at least one preferred example, the method further includes, by the processing circuit system: reducing the target SoC of the battery pack whose estimated temperature exceeds a predetermined threshold temperature to a target SoC whose final temperature of the battery pack does not exceed the predetermined threshold temperature according to a predetermined temperature model.

[0020] Optionally, in some examples, including in at least one preferred example, the method further comprises, by the processing circuit system: determining a threshold temperature of the battery pack based on an expected decrease in the health state of the battery pack with temperature.

[0021] Optionally, in some examples, including in at least one preferred example, the method further includes, by the processing circuit system: estimating the maximum temperature rise rate of each battery pack to reach an initial target SoC using a predetermined temperature model of the battery pack, the temperature and internal resistance of the corresponding battery pack; and determining that the maximum temperature rise rate of the battery pack exceeds a threshold temperature rise rate; and reducing the target SoC of the battery pack whose estimated temperature rise rate exceeds the threshold temperature rise rate.

[0022] Optionally, in some examples, including in at least one preferred example, a computer program product is provided, the computer program product comprising program code, which, when executed by a processing circuit system, performs the method of any of the aforementioned examples.

[0023] Optionally, in some examples, including in at least one preferred example, a non-transitory computer-readable storage medium comprising instructions is provided, which, when executed by a processing circuit system, causes the processing circuit system to perform the method of any of the aforementioned examples.

[0024] Those skilled in the art will appreciate that the disclosed aspects, examples (including any preferred examples), and / or the accompanying claims may be appropriately combined with each other. Additional features and advantages are disclosed in the following description, claims, and drawings, and in part will be apparent to those skilled in the art or recognized by practicing the disclosure as described herein.

[0025] Also disclosed herein are computer systems, control units, code modules, computer-implemented methods, computer-readable media, and computer program products associated with the technical benefits discussed above. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Examples are described in more detail below with reference to the accompanying drawings.

[0027] Figure 1 An example vehicle including a computer system including processing circuitry according to an example.

[0028] Figure 2 is a flow chart of an exemplary method for controlling charging of a battery pack according to an example.

[0029] Figure 3 is a flow chart of an exemplary method for controlling charging of a battery pack according to an example.

[0030] Figure 4 is a flow chart of an exemplary method for controlling charging of a battery pack according to an example.

[0031] Figure 5 is a flow chart of an exemplary method for controlling charging of a battery pack according to an example.

[0032] Figure 6 is a schematic diagram of an exemplary computer system for implementing the examples disclosed herein, according to an example. DETAILED DESCRIPTION

[0033] The detailed description set forth below provides information and examples of the disclosed technology in sufficient detail to enable those skilled in the art to practice the disclosure.

[0034] In an energy storage system including multiple battery packs, battery charging, especially charging at a high state of charge (SoC), may cause a sharp increase in temperature, and the cooling system may not be able to cool it down sufficiently. Therefore, it is desirable to provide a system and method to alleviate this problem.

[0035] Therefore, a first aspect of the present disclosure may seek to avoid overheating and excessive wear of the battery when charging a battery comprising multiple battery packs. Technical benefits may include: equalization of battery pack aging in an energy storage system comprising multiple battery packs, which can both improve the service life of the battery and reduce the risk of overheating during charging.

[0036] Figure 1 A vehicle 160 is schematically shown according to an example including a computer system 100 including a processing circuit system 102. The vehicle shown includes a plurality of battery packs 150a to 150c connected to the processing circuit system 102. Further reference will be made to Figure 2 To describe the functionality of the processing circuit system and the method for controlling the processing circuit system, the figure is a flow chart of an exemplary method for controlling the charging of a battery pack according to an example. It should be understood that the described method includes actions taken by the processing circuit system 102 in the vehicle 160.

[0037] The processing circuit system 102 is configured to: determine 200 the state of charge 201 (SoC) of each of the plurality of battery packs 150a to 150c in the energy storage system 104 of the vehicle, and determine 202 the temperature 203 of each of the plurality of battery packs. For example, the SoC 201 may be determined by measuring the voltage across each of the battery packs 150a to 150c using a voltage sensor, and the temperature may be determined using a temperature sensor configured to measure the temperature of the respective battery packs 150a to 150c. In addition, the method includes determining 204 an internal resistance 205 of each of the plurality of battery packs. The internal resistance 205 indicates the health state of the battery, and also provides information about how to charge the battery pack, such as whether certain current limits need to be set.

[0038] Next, the method includes setting 206 an initial target SoC 207 for a plurality of battery packs, each battery pack having the same initial target SoC 207. The initial target SoC 207 may be, for example, 100%, or may be an SoC lower than 100% if there are limitations such as an available time period or if it is desired to charge the battery to a lower SoC for other reasons (such as to increase the useful life of the battery).

[0039] According to the target SoC, the method includes estimating 208 a final temperature 209 of each battery pack of the initial target SoC 207 from a predetermined temperature model of the battery pack using the temperature 203 and the internal resistance 205 of the corresponding battery pack 150a to 150c. The predetermined temperature model may be an electrothermal model for the type of battery pack used. The predetermined temperature model may also be based on empirical data describing the temperature of the battery packs for different charging parameters. Furthermore, the predetermined temperature model may also utilize a database or a lookup table to estimate the final temperature 209 of a given target SoC 207.

[0040] Furthermore, when it is determined 210 that the estimated final temperature of the battery pack 150a to 150c exceeds the threshold temperature 211, the method includes setting 212 a reduced target SoC 213 for the battery pack 150a to 150c estimated to exceed the threshold temperature 211. The threshold temperature 211 is preferably set so as to ensure that the battery pack is not damaged or suffers from excessive wear and aging during the charging procedure. Furthermore, the reduced target SoC 213 is preferably determined using a predetermined temperature model so that the reduced target SoC 213 does not cause the battery temperature to rise above the threshold temperature.

[0041] If all packs are set to the same SoC, there is a risk of uneven pack aging, as the packs may be unevenly loaded and may age differently due to subtle physical differences between packs. The described system and method will in effect provide for periodic rotation of packs to charge them to a higher SoC, thereby introducing more even aging so that the pack health remains constant.

[0042] Figure 3 is a flow chart of an exemplary method for controlling charging of a battery pack according to an example. Figure 3 The method and system described, the processing circuit system is also configured to: receive 300 an available charger capacity 301 for charging the energy storage system; and set 302 the initial target SoC207 of the multiple battery packs based on the available charger capacity 301. In addition, the received available charger capacity 301 can be at least one of the available charging time 303, the maximum charging power 305, the maximum charging current 307 and the total charging energy 309. Therefore, the initial target SoC 207 can be set to correspond to the capability of the charger to avoid setting an unrealistic target SoC. For example, if the charger is only capable of charging at a specific power, and if the charging time is limited, the entire charging cycle may not achieve the desired SoC. In this scenario, it is best to set a lower initial target SoC that the charger can achieve. Thereby, the risk of exceeding the threshold temperature is reduced.

[0043] Figure 4is a flow chart of an exemplary method for controlling charging of a battery pack according to an example. Figure 4 The method and system described herein, the processing circuit system is further configured to: during charging, when a reduced target SoC is reached, disconnect 400 the battery pack having the reduced target SoC from the energy storage system; and during operation of the vehicle, determine 402 at least one other battery pack has a SoC equal to the reduced target SoC and reconnect 404 the battery pack having the reduced target SoC. Because one or more battery packs charged to a lower SoC will not be used until the other battery packs reach the same SoC, the aging of the battery packs is further equalized, thereby attempting to ensure a balanced load on the battery packs.

[0044] The processing circuit system can also be configured to determine the cooling properties of the energy storage cooling system and estimate the final temperature of the battery pack based on the cooling properties of the energy storage system. The temperature model can be formed using the default cooling properties of the cooling system, for example, the cooling can be specified based on the external temperature. However, the cooling properties may have changed from the default settings due to reasons such as degradation of the cooling system performance or failure or damage to parts of the cooling system. The temperature model can then take the reduced capacity of the cooling system into account when determining the final temperature of the battery pack for a given SoC. In addition, temperature peaks are most likely to occur at high SoCs, so the temperature of the battery pack is likely to increase during the charging cycle.

[0045] The processing circuit system can also be configured to reduce the target SoCs of the plurality of battery packs estimated to exceed the corresponding predetermined threshold temperature to the target SoCs whose final temperature of the battery pack does not exceed the predetermined threshold temperature according to the predetermined temperature model. Therefore, the described method is applicable to any number of battery packs in the energy storage system, and therefore different battery packs can be set to different target SoCs during the charging procedure.

[0046] The processing circuit system may also be configured to determine a threshold temperature for the battery pack based on an expected decrease in the state of health of the battery pack with temperature. Therefore, the SoH may be a limiting parameter in determining to which SoC the battery pack should be charged. Some degradation of the SoH may be allowed, as this is a naturally occurring phenomenon in most known batteries. However, it may be desirable to set a threshold for how much the SoH is allowed to degrade during a charging cycle to ensure that the useful life of the battery is maximized.

[0047] Figure 5 is a flow chart of an exemplary method for controlling charging of a battery pack according to an example. Figure 4The method and system described, the processing circuit system is also configured to: estimate 500 the maximum temperature rise rate 501 of each battery pack to reach the initial target SoC from a predetermined temperature model of the battery pack using the temperature and internal resistance of the corresponding battery pack; and determine 502 that the maximum temperature rise rate of the battery pack exceeds the threshold temperature rise rate 503, and according to the predetermined temperature model, reduce 504 the target SoC of the battery pack estimated to exceed the threshold temperature rise rate to the target SoC of the battery pack that does not exceed the threshold temperature rise rate 505. By predicting the temperature peak that may occur (i.e., the temperature rises rapidly) and setting the SoC to prevent the temperature from rising too quickly, the temperature peak of the battery pack can be avoided.

[0048] The processing circuitry is further configured to control the charging circuitry to charge the battery pack to the lowered target SoC in response to the lowered target SoC of the battery pack.

[0049] Figure 6 600 is a schematic diagram of a computer system 600 for implementing the examples disclosed herein. The computer system 600 is suitable for executing instructions from a computer-readable medium to perform these and / or any functions or processes described herein. The computer system 600 may be connected (e.g., networked) to other machines in a LAN, an intranet, an extranet, or the Internet. Although only a single device is shown, the computer system 600 may include any device collection that executes an instruction set (or multiple instruction sets) individually or jointly to perform any one or more of the methods discussed herein. Therefore, any reference to a computer system, a computing system, a computer device, a computing device, a control system, a control unit, an electronic control unit (ECU), a processor device, a processing circuit, etc. in the present disclosure and / or claims includes a reference to one or more such devices to execute an instruction set (or multiple instruction sets) individually or jointly to perform any one or more of the methods discussed herein. For example, the control system may include a single control unit or multiple control units connected to each other or otherwise communicatively coupled, so that any executed function can be distributed between the control units as needed. In addition, such devices can communicate with each other or with other devices through various system architectures (such as directly or via a controller area network (CAN) bus, etc.).

[0050] The computer system 600 may include at least one computing device or electronic device that can include firmware, hardware and / or execute software instructions to implement the functionality described herein. The computer system 600 may include a processing circuit system 602 (e.g., a processing circuit system including one or more processor devices or control units), a memory 604, and a system bus 606. The computer system 600 may include at least one computing device with a processing circuit 602. The system bus 606 provides an interface for system components (including but not limited to the memory 604 and the processing circuit 602). The processing circuit 602 may include any number of hardware components for performing data or signal processing or for executing computer code stored in the memory 604. The processing circuit system 602 may include, for example, a general-purpose processor, a special-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), a circuit containing a processing component, a group of distributed processing components, a group of distributed computers configured for processing, or other programmable logic devices designed to perform the functions described herein, discrete gate or transistor logic, discrete hardware components, or any combination thereof. The processing circuit system 602 may also include computer executable code that controls the operation of the programmable device.

[0051] The system bus 606 can be any of several types of bus structures, which can be further interconnected to a memory bus (with or without a memory controller), a peripheral bus, and / or a local bus using any of a variety of bus architectures. The memory 604 can be one or more devices for storing data and / or computer code to complete or facilitate the methods described herein. The memory 604 can include a database component, an object code component, a script component, or other types of information structures for supporting various activities herein. Any distributed or local memory device can be utilized with the systems and methods of the present specification. The memory 604 can be communicatively connected to the processing circuit 602 (e.g., via a circuit or any other wired, wireless, or network connection) and can include computer code for performing one or more processes described herein. The memory 604 may include nonvolatile memory 608 (e.g., read-only memory (ROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), etc.) and volatile memory 610 (e.g., random access memory (RAM)) or any other medium that can be used to carry or store desired program code in the form of machine-executable instructions or data structures and that can be accessed by a computer or other machine having the processing circuit 602. A basic input / output system (BIOS) 612 may be stored in the nonvolatile memory 608 and may include the basic routines that help to transfer information between elements within the computer system 600.

[0052] The computer system 600 may also include or be coupled to non-transitory computer-readable storage media such as storage device 614, which may include, for example, an internal or external hard disk drive (HDD) (e.g., enhanced integrated drive electronics (EIDE) or serial advanced technology attachment (SATA)), a HDD for storage (e.g., EIDE or SATA), flash memory, etc. The storage device 614 and other drives associated with computer-readable and computer-usable media may provide non-volatile storage of data, data structures, computer-executable instructions, etc.

[0053] The hard-coded or soft-coded computer code may be provided in the form of one or more modules. The module may be implemented as software and / or hard-coded in the circuit to implement the functions described herein in whole or in part. The module may be stored in a storage device 614 and / or a volatile memory 610 that may include an operating system 616 and / or one or more program modules 618. All or part of the examples disclosed herein may be implemented as a computer program 620 stored on a temporary or non-temporary computer-available or computer-readable storage medium (e.g., a single medium or multiple media) such as a storage device 614, which includes complex programming instructions (e.g., complex computer-readable program code) that cause the processing circuit 602 to perform the actions described herein. Therefore, the computer-readable program code of the computer program 620 may include software instructions for implementing the functionality of the examples described herein when executed by the processing circuit 602. In some examples, storage device 614 may be a computer program product (e.g., a readable storage medium) having computer program 620 stored thereon, wherein at least a portion of computer program 620 may be loadable (e.g., loaded into a processor) for implementing functionality of the examples described herein when executed by processing circuitry 602. Processing circuitry 602 may serve as a controller or control system of computer system 600 for implementing the functionality described herein.

[0054] The computer system 600 may include an input device interface 622 configured to receive input and selections to be transmitted to the computer system 600 when executing instructions, such as from a keyboard, mouse, touch-sensitive surface, etc. Such input devices may be connected to the processor circuit 602 via an input device interface 622 coupled to the system bus 606, but may be connected via other interfaces such as a parallel port, an Institute of Electrical and Electronics Engineers (IEEE) 1394 serial port, a universal serial bus (USB) port, an IR interface, etc. The computer system 600 may include an output device interface 624 configured to forward output to a display, a video display unit (e.g., a liquid crystal display (LCD) or a cathode ray tube (CRT)). The computer system 600 may include a communication interface 626 suitable for communicating with a network as appropriate or as needed.

[0055] The operational actions described in any exemplary aspect of this article are described to provide examples and discussions. The actions may be performed by hardware components, may be embodied in machine executable instructions to cause a processor to perform the actions, or may be performed by a combination of hardware and software. Although the specific order of method actions may be shown or described, the order of actions may be different. In addition, two or more actions may be performed simultaneously or partially simultaneously.

[0056] Example 1. A computer system (100) comprising a processing circuit system (102) configured to: determine (200) a state of charge (201) SoC for each of a plurality of battery packs (150a to 150c) in an energy storage system (104) of a vehicle; determine (202) a temperature (203) for each of the plurality of battery packs; determine (204) an internal resistance (205) for each of the plurality of battery packs; set (206) an initial target SoC (207) for the plurality of battery packs, each battery pack having the same initial target SoC; estimate (208) a final temperature (209) for each battery pack from a predetermined temperature model of the battery pack using the temperature and internal resistance of the corresponding battery pack to obtain an initial target SoC; determine (210) that the estimated final temperature of the battery pack exceeds a threshold temperature (211); and set (212) a reduced target SoC (213) for the battery pack estimated to exceed the threshold temperature.

[0057] Example 2. A computer system according to Example 1, wherein the processing circuit system is further configured to: receive (300) available charger capacity (301) for charging an energy storage system; and set (302) an initial target SoC for the plurality of battery packs based on the available charger capacity.

[0058] Example 3. The computer system of Example 2, wherein the received available charger capacity is at least one of available charging time (303), maximum charging power (305), maximum charging current (307), and total charging energy (309).

[0059] Example 4. A computer system according to any of the preceding examples, wherein the processing circuit system is further configured to: during charging, when a reduced target SoC is reached, disconnect (400) a battery pack having a reduced target SoC from an energy storage system; and during operation of a vehicle, determine (402) that at least one other battery pack has a SoC equal to the reduced target SoC and reconnect (404) the battery pack having the reduced target SoC.

[0060] Example 5. The computer system of Example 1, wherein the processing circuit system is further configured to: determine a cooling property of the energy storage cooling system; and estimate a final temperature of the battery pack based on the cooling property of the energy storage system.

[0061] Example 6. A computer system according to any one of Examples 1 to 5, wherein the processing circuit system is further configured to: reduce the target SoCs of multiple battery packs whose estimated temperatures exceed the corresponding predetermined threshold temperature to the target SoCs whose final temperatures of the battery packs do not exceed the predetermined threshold temperature according to a predetermined temperature model.

[0062] Example 7. The computer system of Example 1, wherein the processing circuitry is further configured to determine a threshold temperature of the battery pack based on an expected decrease in the state of health of the battery pack with temperature.

[0063] Example 8. A computer system according to Example 1, wherein the processing circuit system is further configured to: estimate (500) the maximum temperature rise rate (501) of each battery pack to reach an initial target SoC from a predetermined temperature model of the battery pack using the temperature and internal resistance of the corresponding battery pack; and determine (502) that the maximum temperature rise rate of the battery pack exceeds a threshold temperature rise rate (503); and according to the predetermined temperature model, reduce (504) the target SoC of the battery pack that is estimated to exceed the threshold temperature rise rate to the target SoC of the battery pack that does not exceed the threshold temperature rise rate (505).

[0064] Example 9. The computer system of any of the preceding examples, wherein the processing circuit system is further configured to: in response to a lowered target SoC of a battery pack, control the charging circuit system to charge the battery pack to a lowered target SoC.

[0065] Example 10. A vehicle (160) comprising a computer system according to any one of Examples 1 to 9.

[0066] Example 11. A computer-implemented method, comprising: determining, by a processing circuit system of a computer system, a state of charge (SoC) of each of a plurality of battery packs in an energy storage system of a vehicle; determining a temperature of each of the plurality of battery packs; determining an internal resistance of each of the plurality of battery packs; setting an initial target SoC for the plurality of battery packs, each battery pack having the same initial target SoC; estimating a final temperature of each battery pack from a predetermined temperature model of the battery pack using the temperature and internal resistance of the corresponding battery pack to obtain the initial target SoC; determining that the estimated final temperature of the battery pack exceeds a threshold temperature; and

[0067] A target SoC of the battery pack estimated to exceed the threshold temperature is lowered.

[0068] Example 12. The method according to Example 11, further comprising:

[0069] receiving available charger capacity for charging the energy storage system; and

[0070] The initial target SoC for the plurality of battery packs is set based on the available charger capacity.

[0071] Example 13. The method of Example 11, wherein the received available charger capacity is at least one of available charging time, maximum charging power, maximum charging current, and total charging energy.

[0072] Example 14. A method according to any one of Examples 11 to 13, further comprising, by the processing circuit system: during charging, when a lowered target SoC is reached, disconnecting the battery pack having the lowered target SoC from the energy storage system; and during operation of the vehicle, reconnecting the battery pack having the lowered target SoC when at least one other battery pack has a SoC equal to the lowered target SoC.

[0073] Example 15. The method of any one of Examples 11 to 14, further comprising, by the processing circuit system: receiving a cooling property of an energy storage cooling system; and estimating a final temperature of the battery pack based on the cooling property of the energy storage system.

[0074] Example 16. The method according to any one of Examples 11 to 15, further comprising, by the processing circuit system: reducing the target SoC of the battery pack estimated to exceed a predetermined threshold temperature to a target SoC where the final temperature of the battery pack does not exceed the predetermined threshold temperature according to a predetermined temperature model.

[0075] Example 17. The method of any of Examples 11 to 16 further comprising, by the processing circuit system: determining a threshold temperature of the battery pack based on an expected decrease in the state of health of the battery pack with temperature.

[0076] Example 18. A method according to any one of Examples 11 to 17, further comprising, by the processing circuit system: estimating the maximum temperature rise rate of each battery pack to reach an initial target SoC using a predetermined temperature model of the battery pack, the temperature and internal resistance of the corresponding battery pack; and determining that the maximum temperature rise rate of the battery pack exceeds a threshold temperature rise rate; and reducing the target SoC of the battery pack whose estimated temperature rise rate exceeds the threshold temperature rise rate.

[0077] Example 19. A computer program product comprising program code for performing the method of any one of Examples 11 to 18 when executed by a processing circuit system.

[0078] Example 20. A non-transitory computer-readable storage medium comprising instructions that, when executed by a processing circuit system, cause the processing circuit system to perform the method of any of Examples 11 to 18.

[0079] The terms used herein are only for the purpose of describing specific aspects and are not intended to limit the present disclosure. As used herein, unless the context clearly indicates otherwise, the singular forms "one", "a kind of" and "the" are intended to also include plural forms. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. It should also be understood that the terms "include" and / or "comprising" when used herein indicate the presence of stated features, integers, actions, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, actions, steps, operations, elements, parts and / or their groups.

[0080] It should be understood that although the terms first, second, etc. can be used to describe various elements in this article, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, without departing from the scope of the present disclosure, the first element can be referred to as the second element, and similarly, the second element can be referred to as the first element.

[0081] Relative terms such as "below" or "above" or "upper" or "lower" or "horizontal" or "vertical" may be used herein to describe the relationship of one element to another element, as shown in the accompanying drawings. It should be understood that these terms and those discussed above are intended to cover different device orientations in addition to the orientations depicted in the accompanying drawings. It will be understood that when an element is referred to as being "connected" or "coupled" to another element, the element may be directly connected or directly coupled to the other element, or there may be intervening elements. In contrast, when an element is referred to as being "directly connected to" or "directly coupled to" another element, there are no intervening elements.

[0082] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those commonly understood by those skilled in the art to which the present disclosure belongs. It should also be understood that, unless otherwise clearly defined herein, the terms used herein should be interpreted as meanings consistent with their meanings in the context of this specification and the relevant art, and should not be interpreted in an idealized or overly formal sense.

[0083] It should be understood that the present disclosure is not limited to the aspects described above and shown in the accompanying drawings; rather, those skilled in the art will recognize that many changes and modifications may be made within the scope of the present disclosure and the appended claims. In the drawings and description, various aspects have been disclosed for illustrative purposes only and not for limiting purposes, and the scope of the disclosure is set forth in the appended claims.

Claims

1. A computer system (100) comprising a processing circuit system (102), the processing circuit system being configured to: Determining (200) a state of charge (201) SoC of each of a plurality of battery packs (150a to 150c) in an energy storage system (104) of a vehicle; determining (202) a temperature (203) of each of the plurality of battery packs; determining (204) an internal resistance (205) of each of the plurality of battery packs; Setting (206) initial target SoCs (207) for the plurality of battery packs, each battery pack having the same initial target SoC; estimating (208) a final temperature (209) of each battery pack from a predetermined temperature model of the battery pack using the temperature and the internal resistance of the corresponding battery pack to obtain the initial target SoC; determining (210) that the estimated final temperature of the battery pack exceeds a threshold temperature (211); as well as A reduced target SoC (213) for the battery pack estimated to exceed the threshold temperature is set (212).

2. The computer system of claim 1 , wherein the processing circuit system is further configured to: receiving (300) available charger capacity (301) for charging the energy storage system; and The initial target SoC for the plurality of battery packs is set ( 302 ) based on the available charger capacity.

3. The computer system of claim 2, wherein the received available charger capacity is at least one of available charging time (303), maximum charging power (305), maximum charging current (307), and total charging energy (309).

4. The computer system of any preceding claim, wherein the processing circuitry is further configured to: During charging, when the reduced target SoC is reached, disconnecting the battery pack having the reduced target SoC from the energy storage system (400); and During operation of the vehicle, it is determined (402) that at least one other battery pack has a SoC equal to the reduced target SoC and the battery pack having the reduced target SoC is reconnected (404).

5. The computer system of claim 1 , wherein the processing circuit system is further configured to: Determine the cooling properties of the energy storage cooling system; and A final temperature of the battery pack is estimated based on the cooling properties of the energy storage system.

6. The computer system of any one of claims 1 to 5, wherein the processing circuit system is further configured to: The target SoCs of the plurality of battery packs estimated to exceed the corresponding predetermined threshold temperature are reduced according to the predetermined temperature model to target SoCs where the final temperatures of the battery packs do not exceed the predetermined threshold temperature.

7. The computer system of claim 1 , wherein the processing circuit system is further configured to: A threshold temperature for the battery pack is determined based on an expected decrease in the state of health of the battery pack with temperature.

8. The computer system of claim 1 , wherein the processing circuitry is further configured to: estimating (500) a maximum temperature rise rate (501) for each battery pack to reach the initial target SoC from a predetermined temperature model of the battery pack using the temperature and the internal resistance of the corresponding battery pack; and determining (502) that a maximum temperature rise rate of the battery pack exceeds a threshold temperature rise rate (503); and According to the predetermined temperature model, a target SoC of the battery pack estimated to exceed the threshold temperature rise rate is reduced (504) to a target SoC of the battery pack that does not exceed the threshold temperature rise rate (505).

9. The computer system of any preceding claim, wherein the processing circuitry is further configured to: In response to a lowered target SoC of a battery pack, a charging circuit system is controlled to charge the battery pack to the lowered target SoC.

10. A vehicle (160) comprising the computer system of any one of claims 1 to 9.

11. A computer-implemented method comprising: Through the processing circuitry of the computer system, Determining a state of charge (SoC) of each of a plurality of battery packs in an energy storage system of a vehicle; determining a temperature of each of the plurality of battery packs; determining an internal resistance of each of the plurality of battery packs; Setting initial target SoCs for the plurality of battery packs, each battery pack having the same initial target SoC; estimating a final temperature of each battery pack from a predetermined temperature model of the battery pack using the temperature and the internal resistance of the corresponding battery pack to obtain the initial target SoC; determining that the estimated final temperature of the battery pack exceeds a threshold temperature; as well as A target SoC of the battery pack estimated to exceed the threshold temperature is lowered.

12. The method according to claim 11, further comprising: receiving available charger capacity for charging the energy storage system; as well as The initial target SoC for the plurality of battery packs is set based on the available charger capacity. 13 . The method of claim 11 , wherein the received available charger capacity is at least one of available charging time, maximum charging power, maximum charging current, and total charging energy.

14. A computer program product comprising program code for performing the method of any one of claims 11 to 13 when executed by the processing circuitry.

15. A non-transitory computer-readable storage medium comprising instructions which, when executed by the processing circuitry, cause the processing circuitry to perform the method of any one of claims 11 to 13.

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