Battery management system and method, battery, vehicle, equipment, medium and product

Abstract

The invention provides a battery management system and method, a battery, a vehicle, equipment, a medium and a product, and belongs to the technical field of batteries. And the battery management system is used for managing the battery pack in the battery. The battery includes two battery packs connected by a bidirectional converter. The battery management system comprises two sub-battery management systems which are in signal connection with the bidirectional converter. One of the two sub-battery management systems serves as a master control system, and the other one serves as a slave control system. The main control system is configured to obtain state parameters of the two battery packs, and in response to the fact that the difference value of the state parameters of the two battery packs is larger than a first threshold value, the priority of the battery pack corresponding to the larger state parameter in the charging stage and / or the priority of the battery pack corresponding to the larger state parameter in the discharging stage is set to be higher than that of the other battery pack. The state parameters are used for representing the health state of the battery pack. The service life of the whole battery can be prolonged, so that diversified power utilization requirements can be met more flexibly and reliably.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a battery management system, method, battery, vehicle, device, medium and product. BACKGROUND

[0002] Energy saving and emission reduction is the key to social sustainable development. The rechargeable battery has the characteristics of storing or releasing energy as needed, and is widely used in various electric devices or energy storage systems, and is an important part of promoting energy transformation and sustainable development. For the new energy industry, battery technology is an important factor for its development.

[0003] With the continuous development of technology, the power consumption scene of the electric device is constantly enriched, and the power consumption demand is more diversified. The battery usually has an energy compartment, and the rated capacity of a single energy compartment is difficult to meet the diversified power consumption demand, and a single energy compartment lacks redundancy backup. Once a failure occurs, the electric device will not work, so it is urgent to improve. SUMMARY

[0004] The present application aims to at least solve one of the technical problems in the background art. To this end, one object of the present application is to provide a battery management system, method, battery, vehicle, device, medium and product to improve the flexibility and reliability of battery energy supply.

[0005] Embodiments of the first aspect of the present application provide a battery management system for managing battery packs in a battery. The battery includes two battery packs, which are connected through a bidirectional converter and connected with a high-voltage power supply connection terminal and a charging connection terminal. The battery management system includes two sub-battery management systems connected with the bidirectional converter. One of the two sub-battery management systems is a master control system, and the other is a slave control system. The master control system is configured to obtain state parameters of the two battery packs, and in response to a difference between the state parameters of the two battery packs being greater than a first threshold, set the priority of the battery pack corresponding to the state parameter with a larger value in the charging stage and / or the priority in the discharging stage to be higher than that of the other battery pack, and the state parameter is used to represent the health status of the battery pack.

[0006] In the technical solution of the embodiment of the application, two sub battery management systems are arranged, one of which is used as a master control system. The master control system compares the state parameters of the two battery packs to evaluate the aging difference of the battery packs, and adjusts the priority of charging and discharging when the difference of the state parameters exceeds a first threshold value, and then adjusts the priority of charging and discharging of the battery packs according to the aging difference, so as to coordinate and balance the aging degree of the battery packs, prevent the aging difference from expanding, and improve the service life of the battery as a whole, and flexibly meet diversified power demand. In addition, the redundant design of the sub battery management system enables the remaining sub battery management system to continue to work normally as the master control system when the master control system fails, thereby more reliably meeting diversified power demand.

[0007] In some embodiments, the two sub battery management systems are connected to the two battery packs one by one, and the master control system and the slave control system are configured to calculate the state parameters of the battery packs connected thereto respectively; the slave control system is further configured to send the state parameters of the battery pack connected thereto to the master control system. The state parameters of the two battery packs are calculated separately by the master control system and the slave control system, so that each sub battery management system is responsible for data acquisition of one battery pack, without the need for time-sharing multiplexing of sampling channels, and the accuracy of calculation of the state parameters of the battery packs can be improved. The slave control system sends the state parameters of the battery pack connected thereto to the master control system for summarization, and the master control system arbitrates the priority of the two battery packs in the charging stage / discharge stage based on the state parameters of the two battery packs, so that the sub battery management system normally connected to the bidirectional converter can be used as the master control system, and the sub battery management system abnormally connected to the bidirectional converter can be used as the slave control system, realizing a redundant design.

[0008] In some embodiments, each sub battery management system is connected to two battery packs. In the case where no fault occurs in the two sub battery management systems, the master control system and the slave control system are configured to calculate the parameters of different battery packs respectively, and the slave control system is further configured to send the calculated parameters of the battery pack to the master control system; in the case where a fault occurs in one of the two sub battery management systems, the sub battery management system without fault is used as the master control system to calculate the parameters of the two battery packs. If a fault occurs in one of the two sub battery management systems, the other sub battery management system can be used as the master control system to control the conversion of the charging or discharging mode of the two battery packs. When neither of the two sub battery management systems has a fault, the sampling mode of the two sub battery management systems can also be adjusted according to different requirements, so as to more flexibly and reliably meet diversified power demand.

[0009] In some embodiments, the main control system is configured to determine the priority of the two battery packs in the charging stage and / or the priority of the two battery packs in the discharging stage according to the rated capacity of the two battery packs in response to the difference between the state parameters of the two battery packs being less than or equal to the first threshold. When the state parameters are close to each other, adjusting the charging and discharging priority according to the rated capacity can better match the rated capacity with the power demand, make the best of the respective advantages of the battery packs with different capacities, and improve the overall performance of the battery.

[0010] In some embodiments, the main control system is further configured to set the priority of the battery pack with a larger rated capacity in the charging stage and / or the priority of the battery pack with a larger rated capacity in the discharging stage to be higher than the priority of the battery pack with a smaller rated capacity in response to the difference between the state parameters of the two battery packs being less than or equal to the first threshold. Setting the charging priority or the discharging priority of the battery pack with a larger rated capacity to be higher can make the large-capacity battery reasonably bear the load, make the best of its capacity and cycle performance, reduce the risk of transition cycles of the small-capacity battery pack, and be conducive to achieving synchronous degradation of the two battery packs, thereby improving the overall performance of the battery.

[0011] In some embodiments, the two sub-battery management systems are configured to control the discharging or charging of the two battery packs as the main control system when one of them fails. By making the two sub-battery management systems redundant when a failure occurs, the reliability and continuity of the battery charging and discharging control can be improved.

[0012] In some embodiments, the two battery packs are a first battery pack and a second battery pack, and the main control system is further configured to, in the discharging stage, obtain the state of charge of the first battery pack in response to the difference between the state parameters of the first battery pack and the second battery pack being less than or equal to the first threshold, and control the first battery pack to preferentially discharge to the outside in response to the state of charge of the first battery pack being greater than a second threshold until the state of charge of the first battery pack is less than or equal to the second threshold. A large-capacity battery not only has more storage capacity, but also has the advantages of strong cycle tolerance and stable output power. When the energy of the large-capacity battery is sufficient, the large-capacity battery is preferentially used for power supply, which can reduce the switching frequency of the bidirectional converter, reduce the capacity conversion loss, and reduce the failure probability of the small-capacity battery.

[0013] In some embodiments, the main control system is further configured to, in the discharging stage, control the second battery pack to charge the first battery pack that is discharging or switch the second battery pack to discharge to the outside in response to the state of charge of the first battery pack being less than or equal to the second threshold and the state of charge of the second battery pack being greater than a third threshold. By supplementing the energy of the first battery pack or switching the power supply subject, the risk of over-discharge of the first battery pack is reduced, the continuity of the battery power supply to the outside is improved, the service life of the battery is prolonged, different power demands are flexibly met, and the energy utilization efficiency is improved.

[0014] In some embodiments, the battery is applied to a vehicle, and the two battery groups are respectively a first battery group and a second battery group; the main control system is further configured to: in the discharging phase, in response to a difference between the state parameter of the first battery group and the state parameter of the second battery group being less than or equal to a first threshold value, obtaining a driving state of the vehicle; the driving state includes an intelligent driving mode, a commuting mode or a long-distance mode; in response to the vehicle being in the intelligent driving mode, controlling the state of charge of the second battery group to be greater than or equal to a fourth threshold value; in response to the vehicle being in the commuting mode, controlling the first battery group to discharge externally until the state of charge of the first battery group is less than or equal to a second threshold value, and switching to the second battery group to discharge externally; and in response to the vehicle being in the long-distance mode, controlling the first battery group and the second battery group to discharge externally according to a ratio of the remaining charge of the two battery groups. According to the discharging mode of the battery group controlled according to different driving states, more diversified power demand can be met, and the energy utilization efficiency of the battery can be improved.

[0015] In some embodiments, the main control system is further configured to: in the charging phase, charging the two battery groups according to the priority from high to low; and in response to the charging power exceeding the demand power of the battery group with higher priority among the two battery groups, using the part of the charging power exceeding the demand power to charge the battery group with lower priority among the two battery groups. On the basis of determining the charging sequence based on the priority, the charging control logic is further optimized in combination with the relationship between the charging power and the demand power, and the charging efficiency of the battery is improved.

[0016] In some embodiments, the main control system is further configured to: in the discharging phase, in response to a failure of one of the two battery groups, controlling the other of the two battery groups to discharge externally. The two battery groups can be redundant backups of each other, which can improve the continuity and reliability of battery power supply.

[0017] The embodiment of the second aspect of the application provides a battery control method, applied to a battery, the battery comprising two battery packs and a battery management system, the two battery packs being connected through a bidirectional converter, the battery management system being in signal connection with the bidirectional converter, the battery management system comprising two sub-battery management systems, the method comprising: determining one of the two sub-battery management systems as a master control system and the other as a slave control system; the master control system acquiring state parameters of the two battery packs; and the master control system setting, in response to a difference between the state parameters of the two battery packs being greater than a first threshold, a priority of a battery pack corresponding to a state parameter greater than the other in a charging stage and / or a priority of the battery pack in a discharging stage to be higher than that of the other. One of the two sub-battery management systems is set as the master control system, the master control system evaluates the aging difference of the battery packs by comparing the state parameters of the two battery packs, and triggers the adjustment of the charging and discharging priority when the difference between the state parameters exceeds the first threshold, and then adjusts the charging and discharging priority of the battery packs according to the aging difference, which can coordinate and balance the aging degree of the battery packs, prevent the aging difference from expanding, and is beneficial to improving the service life of the battery as a whole and flexibly meeting diversified power demands. Moreover, the redundant design of the sub-battery management systems enables the remaining sub-battery management system to continue to work normally as the master control system when the master control system fails, thereby more reliably meeting diversified power demands.

[0018] In some embodiments, the two battery packs are connected in one-to-one correspondence with the two sub-battery management systems, the master control system acquires the state parameters of the two battery packs, comprising: the master control system and the slave control system respectively calculating the state parameters of the battery packs connected thereto; and the slave control system sending the state parameters of the battery pack connected thereto to the master control system. The state parameters of the two battery packs are calculated separately by the master control system and the slave control system, so that each sub-battery management system is exclusively responsible for data acquisition of one battery pack, without the need for time-sharing multiplexing of sampling channels, which can improve the accuracy of calculation of the state parameters of the battery packs. The slave control system sends the state parameters of the battery pack connected thereto to the master control system for aggregation, and the master control system arbitrates the priority of the two battery packs in the charging stage / discharge stage based on the difference between the state parameters of the two battery packs, so that the sub-battery management system normally connected with the bidirectional converter can be used as the master control system, and the sub-battery management system abnormally connected with the bidirectional converter can be used as the slave control system, realizing a redundant design.

[0019] In some embodiments, the two battery packs are connected to each of the sub-battery management systems, and the master control system acquires state parameters of the two battery packs, including: in response to no fault occurring in the two sub-battery management systems, the master control system and the slave control system respectively calculate the state parameters of different battery packs, and the slave control system sends the calculated state parameters of the battery pack to the master control system; in response to a fault occurring in one of the two sub-battery management systems, the sub-battery management system without fault functions as the master control system to calculate the state parameters of the two battery packs. If one of the two sub-battery management systems itself has a fault, another sub-battery management system can be used as the master control system to realize control of the change of the charging or discharging mode of the two battery packs. When neither of the two sub-battery management systems has a fault, the sampling mode of the two sub-battery management systems can also be adjusted according to different needs, so that diversified power consumption needs can be more flexibly and reliably met.

[0020] In some embodiments, determining one of the two sub-battery management systems as the master control system and the other as the slave control system includes: determining rated capacities of the two battery packs; in response to no fault occurring in the two sub-battery management systems, in the case that the rated capacities of the two battery packs are different, the sub-battery management system controlling the battery pack with the larger rated capacity functions as the master control system, and the sub-battery management system controlling the other battery pack functions as the slave control system; in response to a fault occurring in one of the two sub-battery management systems, the sub-battery management system without fault functions as the master control system, and the sub-battery management system with fault functions as the slave control system. By using the sub-battery management system controlling the battery pack with the larger rated capacity as the master control system, use of another slave control system can be reduced, resource waste can be reduced, the sub-battery management system without fault can be used as the master control system, redundancy design can be realized, and smooth battery charging and discharging can be ensured.

[0021] In some embodiments, determining one of the two sub-battery management systems as the master control system and the other as the slave control system includes: determining rated cycle times of the two battery packs; in response to no fault occurring in the two sub-battery management systems, in the case that the rated cycle times of the two battery packs are different, the sub-battery management system controlling the battery pack with the larger rated cycle time functions as the master control system, and the sub-battery management system controlling the other battery pack functions as the slave control system; in response to a fault occurring in one of the two sub-battery management systems, the sub-battery management system without fault functions as the master control system, and the sub-battery management system with fault functions as the slave control system. By using the sub-battery management system controlling the battery pack with the larger rated cycle time as the master control system, use of another slave control system can be reduced, resource waste can be reduced, the sub-battery management system without fault can be used as the master control system, redundancy design can be realized, and smooth battery charging and discharging can be ensured.

[0022] In some embodiments, the method further comprises: in response to the difference between the state parameters of the two battery packs being less than or equal to the first threshold, the main control system determines the priority of the two battery packs in the charging stage and / or the priority of the two battery packs in the discharging stage according to the rated capacity of the two battery packs. When the state parameters are similar, adjusting the charging and discharging priority according to the rated capacity can better match the rated capacity with the power demand, maximize the advantages of different capacities of the battery packs, and improve the overall performance of the battery.

[0023] In some embodiments, in response to the difference between the state parameters of the two battery packs being less than or equal to the first threshold, the main control system determines the priority of the two battery packs in the charging stage and / or the priority of the two battery packs in the discharging stage according to the rated capacity of the two battery packs, comprising: in response to the difference between the state parameters of the two battery packs being less than or equal to the first threshold, setting the priority of the battery pack with larger rated capacity in the charging stage and / or the priority of the battery pack with larger rated capacity in the discharging stage to be higher than that of the battery pack with smaller rated capacity. Setting the charging priority or discharging priority of the battery pack with larger rated capacity to be higher can make the large-capacity battery reasonably bear the load, maximize its capacity and cycle performance advantages, reduce the risk of transition cycle of the small-capacity battery pack, and be conducive to achieving synchronous attenuation of the two, thereby improving the overall performance of the battery.

[0024] In some embodiments, the two battery packs are a first battery pack and a second battery pack; the method further comprises: in the discharging stage, in response to the difference between the state parameters of the first battery pack and the second battery pack being less than or equal to the first threshold, the main control system obtains the state of charge of the first battery pack; in response to the state of charge of the first battery pack being greater than a second threshold, the main control system controls the first battery pack to preferentially discharge to the outside until the state of charge of the first battery pack is less than or equal to the second threshold. The large-capacity battery not only has more storage capacity, but also has the advantages of strong cycle tolerance and stable output power. When the power of the large-capacity battery is sufficient, the large-capacity battery is preferentially used for power supply, which can reduce the switching frequency of the bidirectional converter, reduce the capacity conversion loss, and reduce the failure probability of the small-capacity battery.

[0025] In some embodiments, the method further comprises: in the discharging stage, in response to the state of charge of the first battery pack being less than or equal to a second threshold and the state of charge of the second battery pack being greater than a third threshold, the main control system controls the second battery pack to charge the first battery pack that is discharging, or switches the second battery pack to discharge to the outside. The embodiments of the application can reduce the risk of over-discharge of the first battery pack by supplementing power to the first battery pack or switching the power supply subject, improve the continuity of the battery power supply to the outside, be conducive to prolonging the service life of the battery, flexibly cope with different power demands, and improve the energy utilization efficiency.

[0026] In some embodiments, the battery is applied to a vehicle, and the two battery groups are respectively a first battery group and a second battery group; the method further comprises: in the discharging phase, the main control system acquires a driving state of the vehicle in response to a difference between the state parameter of the first battery group and the state parameter of the second battery group being less than or equal to a first threshold value; the driving state comprises an intelligent driving mode, a commuting mode or a long-distance mode; the main control system controls the state of charge of the second battery group to be greater than or equal to a fourth threshold value in response to the vehicle being in the intelligent driving mode; the main control system controls the first battery group to discharge externally until the state of charge of the first battery group is less than or equal to a second threshold value, and then switches to the second battery group to discharge externally in response to the vehicle being in the commuting mode; and the main control system controls the first battery group and the second battery group to discharge externally in proportion to the remaining charge of the two battery groups in response to the vehicle being in the long-distance mode. According to the above method, the discharging mode of the battery group is controlled according to different driving states, so that diversified power demands can be met, and the energy utilization efficiency of the battery is improved.

[0027] In some embodiments, the method further comprises: in the charging phase, the main control system charges the two battery groups according to the priority from high to low; and the main control system uses the part of the charging power exceeding the demand power of the battery group with higher priority to charge the battery group with lower priority in response to the charging power exceeding the demand power of the battery group with higher priority. According to the above method, the charging control logic is optimized by further combining the relationship between the charging power and the demand power on the basis of determining the charging sequence according to the priority, so that the charging efficiency of the battery is improved.

[0028] In some embodiments, the method further comprises: in the discharging phase, the main control system controls the other one of the two battery groups to discharge externally in response to one of the two battery groups failing. According to the above method, the two battery groups can be mutually redundant backups, so that the continuity and reliability of the battery power supply are improved.

[0029] Embodiments of the third aspect of the present application provide a battery, comprising: two battery groups connected through a bidirectional converter, and a battery management system for managing the battery groups, the battery management system being the battery management system in the above embodiments, or the battery management system being used in the battery control method in the above embodiments.

[0030] Embodiments of the fourth aspect of the present application provide a vehicle, comprising the battery as above, the battery being used to provide electric energy.

[0031] Embodiments of the fifth aspect of the present application provide a computing device, comprising at least one processor; and at least one memory communicatively connected to the at least one processor, the at least one memory storing instructions which, when executed by the at least one processor alone or collectively, cause the computing device to perform the above battery control method.

[0032] The embodiment of the sixth aspect of the present application provides a computer readable storage medium storing instructions, which, when executed by one or more processors of a computing device alone or in combination, cause the computing device to perform the battery control method.

[0033] The embodiment of the seventh aspect of the present application provides a computer program product comprising instructions, which, when executed by one or more processors of a computing device alone or in combination, cause the computing device to perform the battery control method.

[0034] The above description is only a summary of the technical solutions of the present application. In order to enable one skilled in the art to better understand the technical means of the present application and to implement the same according to the contents of the description, and in order to enable the above and other purposes, characteristics and advantages of the present application to be more apparent and easy to understand, the following specific embodiments of the present application are described. BRIEF DESCRIPTION OF DRAWINGS

[0035] In the drawings, like reference numerals refer to same or similar components throughout the several views. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments in accordance with the present disclosure and should not be considered limiting of the scope of the present application.

[0036] Figure 1 Structure diagram of a vehicle for some embodiments of the present application; Figure 2 Exploded structure diagram of a battery for some embodiments of the present application; Figure 3 Structure diagram of a battery for some embodiments of the present application; Figure 4 Structure diagram of a battery for some embodiments of the present application; Figure 5 Structure diagram of a battery for some embodiments of the present application; Figure 6 Flowchart of a battery control method for some embodiments of the present application; Figure 7 Flowchart of a battery control method for some embodiments of the present application.

[0037] Explanation of reference numerals: Vehicle 1000; Battery 100, controller 200, motor 300; Box 10, first part 11, second part 12, battery cell 20; The first battery pack 110, the second battery pack 120, the bidirectional converter 130, the high-voltage power supply connection terminal 140, the charging connection terminal 150, the sub-battery management system 160, the first sub-battery management system 161, the second sub-battery management system 162, and the battery control method 400. DETAILED DESCRIPTION

[0038] The embodiments of the technical solutions of the present application will be described in detail below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application; the terms "comprising" and "having," and any variations thereof, as used in the specification and claims and the aforementioned drawings, are intended to cover a non-exclusive inclusion.

[0040] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise explicitly and specifically limited.

[0041] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily mutually exclusive or alternative to other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0042] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects are a "or" relationship.

[0043] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two), and similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0044] In the description of the embodiments of the present application, the orientations or positional relationships indicated by the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0045] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connecting", "connecting", "fixing" and the like should be understood broadly, for example, can be fixedly connected, or can be detachably connected, or can be integrated; can be mechanically connected, or can be electrically connected; can be directly connected, or can be indirectly connected through an intermediate medium, or can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0046] At present, from the development of market situation, the application of rechargeable batteries is more and more extensive. Rechargeable batteries are not only applied to energy storage power systems such as hydroelectric, thermal, wind and solar power stations, but also widely used in various electronic devices, such as electric bicycles, electric motorcycles, electric vehicles and other electric vehicles, military equipment, aerospace and other fields. With the continuous expansion of the application field of rechargeable batteries, the market demand is also increasing.

[0047] With the continuous development of technology, the power consumption scene of the power consumption device is constantly enriched, and the power consumption demand is more diversified. The battery device is usually provided with an energy cabin. The rated capacity of a single energy cabin is too large, which leads to a significant increase in cost, and the capacity is too small, which is difficult to meet the diversified power consumption demand, and once a single energy cabin fails, the power consumption device cannot work, and lacks redundancy design.

[0048] In order to meet the diversified power consumption demand, the present application provides a battery, which comprises a first battery pack and a second battery pack connected through a bidirectional converter. In this way, the two battery packs can be charged and discharged as independent energy cabins, can be discharged together, and one battery pack can be responsible for discharging, and the other battery pack can be used to supplement the energy of the battery pack.

[0049] For cost control, the two battery packs can be designed differently in terms of chemical system, number of battery cells contained, etc., so that the voltage platforms of the two battery packs are different. After the two battery packs are connected through the bidirectional converter, they can realize common discharging or charging, or mutual charging, so as to balance the power supply capacity and cost. However, the different design of the two battery packs may bring higher requirements and greater difficulty to the energy management of the battery device.

[0050] Based on the above considerations, the embodiments of the present application provide a battery management system for managing battery packs in a battery. The battery includes two battery packs connected through a bidirectional converter. The battery management system includes two sub-battery management systems in signal connection with the bidirectional converter. One of the two sub-battery management systems serves as a master control system, and the other serves as a slave control system. The master control system is configured to: acquire state parameters of the two battery packs, and in response to a difference between the state parameters of the two battery packs being greater than a first threshold, set a priority of the battery pack corresponding to the state parameter with a larger value in a charging phase and / or a priority of the battery pack in a discharging phase to be higher than that of the other battery pack, the state parameter being used to represent a health state of the battery pack.

[0051] By setting two sub-battery management systems, one of which serves as a master control system, the master control system can evaluate the aging difference between the battery packs by comparing the state parameters of the two battery packs, and trigger adjustment of the charging and discharging priorities when the difference between the state parameters exceeds the first threshold, so as to adjust the charging and discharging priorities of the battery packs according to the aging difference. In this way, the aging degrees of the battery packs can be coordinated and balanced, the aging difference between the two battery packs can be prevented from expanding, and the overall service life of the battery can be improved, so as to flexibly meet diversified power demands. Moreover, the redundant design of the sub-battery management systems enables the remaining sub-battery management system to continue to work normally as the master control system when the master control system fails, so as to more reliably meet diversified power demands.

[0052] The battery cell disclosed in the embodiments of the present application can be used in, but is not limited to, an electric device or an energy storage device such as a vehicle, a ship or an aircraft. The power supply system of the electric device or the energy storage device can be composed of the battery cell and the battery disclosed in the present application. In this way, the overall service life of the battery can be improved, so as to more flexibly and reliably meet diversified power demands.

[0053] The embodiments of the present application provide an electric device using a battery as a power supply. The electric device can be, but is not limited to, a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, an electric vehicle, an electric automobile, a ship, a spacecraft, etc. The electric toy can include a fixed or mobile electric toy, such as a game console, an electric automobile toy, an electric ship toy, an electric aircraft toy, etc. The spacecraft can include an airplane, a rocket, a space shuttle, a spacecraft, etc.

[0054] The following embodiments are described by taking a vehicle 1000 as an example for convenience of illustration.

[0055] Please refer to Figure 1 , Figure 1 A structural schematic diagram of a vehicle is provided for some embodiments of the present application. The vehicle 1000 can be a fuel automobile, a gas automobile or a new energy automobile, and the new energy automobile can be a pure electric automobile, a hybrid electric automobile or a range extended automobile, etc. The vehicle 1000 is internally provided with a battery 100, which can be arranged at the bottom, head or tail of the vehicle 1000. The battery 100 can be used for power supply of the vehicle 1000, for example, the battery 100 can be used as an operating power supply of the vehicle 1000. The vehicle 1000 can further include a controller 200 and a motor 300, and the controller 200 is used to control the battery 100 to supply power to the motor 300, for example, to meet the power demand of the vehicle 1000 during starting, navigation and driving.

[0056] In some embodiments of the present application, the battery 100 can not only be used as an operating power supply of the vehicle 1000, but also be used as a driving power supply of the vehicle 1000, to replace or partially replace fuel or natural gas to provide driving power for the vehicle 1000.

[0057] Please refer to Figure 2 , Figure 2 A structural schematic diagram of a battery is provided for some embodiments of the present application. The battery 100 includes a box body 10 and a battery monomer 20, and the battery monomer 20 is accommodated in the box body 10. The box body 10 is used to provide an accommodation space for the battery monomer 20, and the box body 10 can adopt various structures. In some embodiments, the box body 10 can include a first part 11 and a second part 12, and the first part 11 and the second part 12 are mutually covered. The first part 11 and the second part 12 jointly define an accommodation space for accommodating the battery monomer 20. The second part 12 can be a hollow structure with one end open, and the first part 11 can be a plate-shaped structure, which is covered on the open side of the second part 12 to jointly define the accommodation space with the second part 12. The first part 11 and the second part 12 can also be hollow structures with one side open, and the open side of the first part 11 is covered on the open side of the second part 12. Of course, the box body 10 formed by the first part 11 and the second part 12 can have various shapes, such as a cylinder, a cuboid, etc.

[0058] In the battery 100, the battery cells 20 can be multiple, and the multiple battery cells 20 can be connected in series or in parallel or in a mixed manner. The mixed manner means that the multiple battery cells 20 are connected in series and in parallel. The multiple battery cells 20 can be directly connected in series or in parallel or in a mixed manner, and then the multiple battery cells 20 are accommodated in the box body 10 as a whole. Of course, the battery 100 can also be that the multiple battery cells 20 are connected in series or in parallel or in a mixed manner to form a battery module, and then the multiple battery modules are connected in series or in parallel or in a mixed manner to form a whole and are accommodated in the box body 10. The battery 100 can also include other structures, for example, the battery 100 can also include a current collecting component for realizing the electrical connection between the multiple battery cells 20.

[0059] Each battery cell 20 can be a secondary battery or a primary battery, and can also be a lithium-sulfur battery, a sodium-ion battery or a magnesium-ion battery, but is not limited thereto. The battery cell 20 can be in the shape of a cylinder, a flat body, a cuboid or other shapes.

[0060] The embodiments of the present application provide a battery management system for managing a battery pack in a battery. Please refer to Figure 3 , Figure 3 Fig. 1 is a schematic diagram of a battery provided by some embodiments of the present application. The battery 100 includes two battery packs and a bidirectional converter. The two battery packs can be a first battery pack 110 and a second battery pack 120, which are connected through the bidirectional converter 130 and connected with a high-voltage power supply connection terminal 140 and a charging connection terminal 150.

[0061] The battery management system includes two sub-battery management systems connected with the bidirectional converter. One of the two sub-battery management systems is a master control system, and the other is a slave control system. The master control system is configured to obtain state parameters of the two battery packs, and in response to a difference between the state parameters of the two battery packs being greater than a first threshold, set a priority of the battery pack corresponding to the state parameter with a larger value in a charging stage and / or a priority in a discharging stage to be higher than that of the other battery pack. The state parameter is used to represent the health status of the battery pack.

[0062] The first battery pack 110 and the second battery pack 120 can be two relatively independent battery packs, and any battery pack can include multiple battery cells or multiple battery modules.

[0063] The first battery pack 110 and the second battery pack 120 can be two relatively independent energy compartments in the battery 100. For example, the box body 10 of the battery 100 can form two relatively independent accommodating cavities for accommodating the first battery pack 110 and the second battery pack 120, respectively.

[0064] The rated capacities of the first battery pack 110 and the second battery pack 120 can be the same or different, and the electrode materials of the two can be the same or different. In some embodiments, the first battery pack 110 and the second battery pack 120 themselves have different capacities, so that one or both of the battery packs can be controlled to provide power according to different power consumption requirements, not only to meet diversified power consumption requirements, but also to serve as backup power for each other, to supplement power for the other battery pack, or to partially or completely replace the other battery pack to supply power externally.

[0065] It can be understood that the battery pack can also include three or more battery packs, and any two of them can serve as the first battery pack 110 and the second battery pack 120 of the embodiments of the present application.

[0066] The high-voltage power supply connection terminal 140 is used to connect with a load to provide power to the load. The load can be a drive motor of a vehicle, a thermal management system, and other high-voltage loads. The charging connection terminal 150 is used to connect with an external charging device to receive power provided by the external charging device.

[0067] The bidirectional converter 130 can be a bidirectional direct current-direct current converter (bidirectional DCDC), which has the core function of enabling bidirectional flow of current between two battery packs with different voltages or states, thereby achieving more flexible battery charging and discharging control. Illustratively, the output end of the bidirectional converter is connected to the positive and negative electrodes of the first battery pack, the input end of the bidirectional converter is connected to the positive and negative electrodes of the second battery pack, and the positive and negative electrodes of the first battery pack are respectively connected to the high-voltage power supply connection terminal 140 and the charging connection terminal 150.

[0068] For cost control considerations, the chemical systems and the number of battery cells contained in the two battery packs can be designed differently, so that the voltage platforms of the two battery packs are different, and they can achieve common discharging or charging externally or mutual charging through the bidirectional converter.

[0069] Illustratively, when both the first battery pack 110 and the second battery pack 120 are normal, after being connected to high voltage, the first battery pack 110 continues to supply power to the load because it is directly connected to the high-voltage power supply connection terminal 140. When the bidirectional converter is turned on, the second battery pack 120 is connected to the high-voltage power supply connection terminal 140 through the bidirectional converter, and thus also supplies power to the load together with the first battery pack 110. If the voltage of the second battery pack 120 is greater than the required voltage of the load at this time, the second battery pack 120 will also charge the first battery pack 110. When the bidirectional converter is turned off, the second battery pack 120 cannot be connected to the high-voltage power supply connection terminal 140, and at this time only the first battery pack 110 supplies power to the load.

[0070] When the first battery pack 110 fails and the second battery pack 120 is normal, the first battery pack 110 cannot supply power to the load, the bidirectional converter is opened, and the second battery pack 120 can supply power to the load through the bidirectional converter connected to the high-voltage power supply connection terminal 140.

[0071] When both the first battery pack 110 and the second battery pack 120 fail, neither of the first battery pack 110 and the second battery pack 120 can supply power to the load.

[0072] One of the two sub-battery management systems can be a master control system, and the other of the two sub-battery management systems can be a slave control system when neither of the two sub-battery management systems fails. When one of the two sub-battery management systems fails, the sub-battery management system that does not fail can be a master control system.

[0073] In some embodiments, when neither of the two sub-battery management systems fails, if the rated capacities of the two battery packs are different and the two battery packs are connected to the two sub-battery management systems one-to-one, the sub-battery management system connected to the battery pack with the larger rated capacity can be a master control system, and the sub-battery management system connected to the battery pack with the smaller rated capacity can be a slave control system. The rated capacity of a battery pack refers to the maximum amount of electricity that the battery pack can discharge under standard conditions (specific temperature, discharge rate, and cutoff voltage), and is a reference value for measuring the storage capacity of the battery pack, usually in ampere-hours (Ah) or watt-hours (Wh, Wh = Ah x voltage).

[0074] In some other embodiments, when neither of the two sub-battery management systems fails, if the rated cycle times of the two battery packs are different and the two battery packs are connected to the two sub-battery management systems one-to-one, the sub-battery management system connected to the battery pack with the more rated cycle times can be a master control system, and the sub-battery management system connected to the battery pack with the less rated cycle times can be a slave control system. The rated cycle time of a battery pack refers to the total number of charge and discharge cycles that the battery cells of the battery pack undergo when the capacity decreases to a certain percentage (usually 80%) of the rated capacity under standard charge and discharge conditions, and is an expected value for measuring the service life of the battery.

[0075] The master control system can change the discharge mode or the charge mode of the two battery packs by controlling the bidirectional converter.

[0076] The state parameter can be any parameter that can represent the health state of the battery pack, such as voltage, voltage response speed, equalization current, equalization interval time, internal resistance, etc., which can reflect the degree of capacity attenuation and internal resistance increase of the battery cell. For example, the state parameter can be the state of health (SOH) of the battery.

[0077] The State of Health (SOH) of a battery pack is a key indicator for measuring the degree of degradation of the battery pack's current performance relative to its brand-new state. It is usually expressed as a percentage, with 100% representing a brand-new state and 0% representing complete failure.

[0078] The SOH of a battery pack can be calculated as the ratio of the current actual usable capacity to the rated capacity (or design capacity) at the time of manufacture. The formula is: SOH = (Current actual capacity / Rated capacity) × 100%. For example, if a brand new battery pack has a rated capacity of 100Ah, and after a period of use, the actual capacity of the battery pack is only 80Ah, then its SOH is 80%.

[0079] like Figure 4 As shown, in some embodiments, the sub-battery management system 160 may include a BMU (Battery Management Unit) and a CMC (Cell Module Controller). The CMC is responsible for collecting data such as voltage, current, and temperature of the battery pack, and transmits this data to the BMU via daisy-chain communication. The BMU can calculate state parameters such as SOH of the battery pack based on the basic data collected by the CMC. The BMU can also determine the priority of the two battery packs during the charging phase and / or the discharging phase based on the state parameters of the two battery packs.

[0080] In some embodiments, the two battery packs can be connected one-to-one with two sub-battery management systems 160. That is, both the main control system and the slave control system are connected to one battery pack. The main control system and the slave control system can collect data such as voltage, current, and temperature of the battery packs they are connected to in real time, and estimate the state of equilibrium (SOH) of the battery packs using algorithms, such as open-circuit voltage method, impedance analysis method, or large model algorithm based on machine learning based on real-time current and voltage curves. Then, the slave control system sends the SOH of its connected battery packs to the main control system for aggregation.

[0081] In other embodiments, each sub-battery management system 160 can connect to two battery packs. The main control system can be responsible for collecting data such as voltage, current, and temperature of the two battery packs in real time and estimating the SOH of the two battery packs using an algorithm. Alternatively, the main control system and the slave control system can collect data such as voltage, current, and temperature of different battery packs respectively, and estimate the SOH of the battery packs using an algorithm. The slave control system then sends the calculated SOH of the battery packs to the main control system for aggregation.

[0082] Based on the difference in the state parameters of the two battery packs, the difference in their aging levels can be determined, and at least one of the priorities of the charging stage and the discharging stage can be determined accordingly.

[0083] The priority of the charging stage refers to the order of meeting the charging demand of the battery packs under the same conditions from high to low according to the priority. Similarly, the priority of the discharging stage refers to the order of discharging the battery packs with high priority first under the same conditions. In this way, by adjusting the priority of the charging stage and the discharging stage of the battery packs, the number of times of participating in the charging and discharging cycle of the battery packs can be adjusted, and the difference in the state of health between different battery packs, that is, the difference in the cycle life, can be balanced, so that the aging degree of the two is kept within a certain range, and the overall life of the battery is improved.

[0084] For example, when the state parameter of the first battery pack 110 is greater than the state parameter of the second battery pack 120, it is considered that the second battery pack 120 is more aged, and at least one of the priority of the charging stage and the priority of the discharging stage of the second battery pack 120 can be set to be lower than that of the first battery pack 110, so that the first battery pack 110 performs more charging and discharging cycles than the second battery pack 120, thereby reducing the difference in the aging degree between the two.

[0085] The first threshold value can be determined according to the capacity attenuation characteristics, power demand, detection accuracy of the battery management system, and other factors of the two battery packs.

[0086] If the first threshold value is set too small, the SOH detection accuracy error may occur, leading to incorrect adjustment, or the charging and discharging priority of the battery packs is adjusted frequently, causing the battery management system to repeatedly switch the charging and discharging priority, resulting in system voltage and current fluctuations. If the first threshold value is set too large, the adjustment of the charging and discharging priority of the two battery packs may not be timely, which may increase the risk of overcharging or overdischarging of the low SOH battery pack, and the overall performance of the battery is affected by the low SOH battery pack.

[0087] In some embodiments, the first threshold value can be in the range of 5%-15%, for example, it can be 5%, 8%, 10%, 12%, 15%, or a value between any two of the above values.

[0088] In some embodiments, the first threshold value can be a fixed value set in advance, or a threshold value dynamically adjusted according to the detection results of the battery management system, for example, the first threshold value can be further adjusted dynamically according to the electrochemical impedance spectroscopy detection results of the battery packs to determine whether the first threshold value is appropriate, so as to keep the difference in the aging degree between the two battery packs within an acceptable range.

[0089] When the difference in the state parameter exceeds the first threshold value, the adjustment of the charging and discharging priority is triggered, which can better control the aging difference between the two battery packs, thereby improving the overall performance of the battery.

[0090] In some embodiments, the priority of the single battery pack charging phase and the priority of the discharging phase are adjusted synchronously, that is, the priority of charging is also the priority of discharging, which is more conducive to the complete regulation of the cycle number of the battery pack.

[0091] It can be understood that the battery control method of the embodiments of the present application can be implemented periodically or aperiodically in the whole life cycle of the battery, for example, the charging priority and the discharging priority of the battery pack can be automatically executed and adjusted periodically after setting a time interval, or can be dynamically executed in real time according to the change of the state parameter.

[0092] Two sub-battery management systems 160 are provided, one of which is a master control system. The master control system evaluates the aging difference of the battery packs by comparing the state parameters of the two battery packs, and triggers the adjustment of the charging and discharging priority when the difference of the state parameters exceeds the first threshold value, and then adjusts the charging and discharging priority of the battery packs according to the aging difference, which can coordinate and balance the aging degree of the battery packs, prevent the aging difference from expanding, and is conducive to improving the overall service life of the battery and flexibly meeting diversified power demand. And the redundant design of the sub-battery management system 160 makes the remaining sub-battery management system continue to work normally as the master control system when the master control system fails, so as to more reliably meet the diversified power demand.

[0093] Reference Figure 3 According to some embodiments of the present application, two sub-battery management systems are connected one-to-one with two battery packs, and the master control system and the slave control system are configured to calculate the state parameters of the battery packs connected thereto respectively; the slave control system is further configured to send the state parameters of the battery pack connected thereto to the master control system.

[0094] Exemplarily, the two sub-battery management systems 160 are a first sub-battery management system 161 and a second sub-battery management system 162, the first sub-battery management system 161 is connected to the first battery pack 110, and the second sub-battery management system 162 is connected to the second battery pack 120. The first sub-battery management system 161 is used to collect the basic data of the first battery pack 110 and preprocess it to obtain the required state parameters of the first battery pack, and the second sub-battery management system 162 is used to collect the basic data of the second battery pack 120 and preprocess it to obtain the required state parameters of the second battery pack.

[0095] In some embodiments, the signal interaction and data communication between the two sub-battery management systems can be realized through a controller area network (CAN), RS-485, isolated serial peripheral interface (isoSPI), universal asynchronous receiver-transmitter (UART), or integrated circuit bus (I2C) bus interface, and a unified protocol between the two sub-battery management systems. For example, the slave control system can actively send the state parameters of the battery pack to the master control system at a preset period (e.g., 100 ms). For example, the master control system can also send a state parameter reading instruction to the slave control system, and the slave control system returns the state parameters of the battery pack after receiving the state parameter reading instruction.

[0096] In the above technical solution, the state parameters of the two battery packs are calculated separately by the master control system and the slave control system, so that each sub-battery management system 160 is responsible for data acquisition of one battery pack, without the need for time-sharing multiplexing of sampling channels, which can improve the accuracy of the calculation of the state parameters of the battery pack. The slave control system sends the state parameters of the battery pack connected thereto to the master control system for summarization, and the master control system arbitrates the priority of the two battery packs in the charging stage / discharge stage based on the state parameters of the two battery packs. In this way, the sub-battery management system 160 normally connected with the bidirectional converter can be used as the master control system, and the sub-battery management system 160 abnormally connected with the bidirectional converter can be used as the slave control system, realizing the redundant design.

[0097] Reference Figure 5 According to some embodiments of the present application, each sub-battery management system is connected with two battery packs. In the case where no fault occurs in the two sub-battery management systems, the master control system and the slave control system are configured to calculate the parameters of different battery packs, respectively, and the slave control system is further configured to send the calculated parameters of the battery pack to the master control system. In the case where a fault occurs in one of the two sub-battery management systems, the sub-battery management system without fault functions as the master control system to calculate the parameters of the two battery packs.

[0098] When a fault occurs in one of the two sub-battery management systems 160, the sub-battery management system 160 without fault functions as the master control system, and the sub-battery management system 160 with fault can stop being used. The master control system can directly obtain the state parameters of the two battery packs without the participation of the other sub-battery management system with fault.

[0099] In some embodiments, the sub battery management system 160 can extend the voltage, temperature sampling channel, such as switching two battery pack signals by multiplexing the multiplexer, independently configuring two sets of total current / voltage sensors, multiplexing the same MCU and communication interface (such as CAN bus), and distinguishing the two sets of data by address. Independent areas are divided in the memory of the sub battery management system 160, and the raw data of the cell voltage, temperature, current, and SOH intermediate variables of the two groups are respectively stored. The SOH of the two groups is alternately calculated at a fixed period, and the respective calibration parameters such as rated capacity and aging coefficient are called.

[0100] In the above technical solution, if one of the two sub battery management systems 160 itself fails, the other sub battery management system 160 can be used as the main control system to realize the control of the change of the charging or discharging mode of the two battery packs. When neither of the two sub battery management systems 160 fails, the sampling mode of the two sub battery management systems 160 can also be adjusted according to different needs, so as to more flexibly and reliably meet diversified power demand.

[0101] According to some embodiments of the present application, the main control system is configured to: in response to the difference between the state parameters of the two battery packs being less than or equal to a first threshold value, determining the priority of the two battery packs in the charging phase and / or the priority of the two battery packs in the discharging phase according to the rated capacity of the two battery packs.

[0102] When the difference between the state parameters of the two battery packs is less than or equal to the first threshold value, it means that the aging degrees of the two battery packs are close. At this time, if the priority is still frequently adjusted, the calculation power consumption of the battery management system and the energy loss of the bidirectional converter will be increased. At this time, the priority of charging and discharging can be determined according to the size of the rated capacity of the two battery packs.

[0103] The rated capacities of the two battery packs are different. In some examples, the electrode assemblies of the battery monomers in the two battery packs can adopt different chemical systems, for example, they can be lithium iron phosphate system and ternary system respectively. The difference between such chemical systems can cause the rated capacities of the battery packs to be different. In other examples, the two battery packs can also respectively contain different numbers of battery monomers or battery modules, so that the rated capacities of the two battery packs can also be different. Selecting battery packs with different rated capacities can flexibly select a suitable power supply according to power demand, thereby meeting diversified power demand.

[0104] The way in which the main control system obtains the rated capacities of the two battery packs can refer to the related description in the above embodiments, which will not be repeated here.

[0105] When the state parameters are close, adjusting the charging and discharging priority according to the size of the rated capacity can better match the rated capacity and the power demand, and can maximize the advantages of different capacity battery packs, thereby improving the overall performance of the battery.

[0106] According to some embodiments of the present application, the main control system is further configured to: in response to the difference between the state parameters of the two battery packs being less than or equal to a first threshold value, setting the priority of the battery pack with larger rated capacity in the charging stage and / or the priority of the battery pack with larger rated capacity in the discharging stage to be higher than that of the battery pack with smaller rated capacity.

[0107] The main control system determines the priority of the two battery packs in the charging stage according to the difference between the state parameters of the two battery packs and the difference between the rated capacities. In some examples, the priority of the battery pack with larger capacity in the charging stage and the priority of the battery pack with larger capacity in the discharging stage can be set to be higher than that of the battery pack with smaller rated capacity.

[0108] In the charging stage, the charging connection terminal 150 is connected with the charging pile, and the main control system controls the bidirectional converter 130 to switch to the "high-priority battery pack charging mode" according to the set priority, so as to convert the external charging pile into a voltage / current suitable for the high-priority battery pack, thereby realizing charging of the high-priority battery pack first; when the high-priority battery pack approaches full charge, for example, the state of charge reaches 95%, the main control system controls the bidirectional converter 130 to switch to the "low-priority battery pack charging mode", so as to charge the low-priority battery pack with external power, and also monitor the state of charge and voltage thereof until the state of charge reaches 95%.

[0109] In the discharging stage, the high-voltage power supply connection terminal 140 is connected with the load, and the main control system controls the bidirectional converter 130 to switch to the "high-priority battery pack discharging mode" according to the set priority, so as to allow the high-priority battery pack to directly supply power to the external load (such as a vehicle-mounted motor or an energy storage load), while monitoring the discharging current and cutoff voltage thereof. If the output power of the high-priority battery pack can completely meet the load demand, only the high-priority battery pack supplies power; if the load power exceeds the maximum output power of the high-priority battery pack, the main control system controls the bidirectional converter 130 to switch to the "double-battery pack cooperative discharging mode", so as to allow the low-priority battery pack to supply power in parallel with the high-priority battery pack after converting the voltage by the bidirectional converter 130, thereby supplying power to the load together.

[0110] Setting the charging priority or discharging priority of the battery pack with larger rated capacity to be higher can make the large-capacity battery reasonably bear the load, play its capacity and cycle performance advantages, reduce the risk of over-cycling of the small-capacity battery pack, and be conducive to realizing synchronous attenuation of the two battery packs and improving the overall performance of the battery.

[0111] According to some embodiments of the present application, the two sub-battery management systems are configured to control the discharging or charging of the two battery packs as the main control system when one of them fails.

[0112] The two sub-battery management systems 160 can be a first sub-battery management system 161 and a second sub-battery management system 162. When one of the first sub-battery management system 161 and the second sub-battery management system 162 fails, the other one will switch to become the main control system, and at the same time, be used to perform the charge and discharge management of the two battery packs, thereby forming a redundant backup.

[0113] In some examples, when the first sub-battery management system 161 fails, the second sub-battery management system 162 can perform the charge and discharge control on the first battery pack 110 by controlling the bidirectional converter 130.

[0114] By making the two sub-battery management systems 160 redundant to each other in case of failure, the reliability and continuity of the battery charge and discharge control can be improved.

[0115] According to some embodiments of the present application, the two battery packs are a first battery pack and a second battery pack, and the main control system is further configured to: in the discharging phase, in response to a difference between the state parameter of the first battery pack and the state parameter of the second battery pack being less than or equal to a first threshold value, obtaining the state of charge of the first battery pack; and in response to the state of charge of the first battery pack being greater than a second threshold value, controlling the first battery pack to preferentially discharge to the outside until the state of charge of the first battery pack is less than or equal to the second threshold value.

[0116] The state of charge (SOC) is an index describing the current remaining capacity of the battery, usually expressed in percentage. The state of charge of the battery pack can be collected by the CMC and sent to the MCU.

[0117] The second threshold value can be set according to the charge and discharge characteristics of the battery pack and the specific power demand. In some embodiments, the value range of the second threshold value can be 15%-30%, for example, it can be 15%, 20%, 25% or 30%.

[0118] When the SOC of the first battery pack 110 is greater than the second threshold value, it means that the first battery pack 110 with a larger rated capacity has relatively abundant electric energy, and in the discharging process, the first battery pack 110 is preferentially controlled to supply power to the load.

[0119] The large-capacity battery not only has more storage capacity, but also has the advantages of strong cycle resistance and stable output power. When the electric energy of the large-capacity battery is sufficient, it is preferentially used to supply power, which can reduce the switching frequency of the bidirectional converter 130, reduce the capacity conversion loss, and reduce the failure probability of the small-capacity battery.

[0120] According to some embodiments of the present application, the main control system is further configured to: in the discharging phase, in response to the state of charge of the first battery pack being less than or equal to the second threshold value and the state of charge of the second battery pack being greater than a third threshold value, control the second battery pack to charge the first battery pack being discharged, or switch the second battery pack to discharge externally.

[0121] The third threshold value is the energy supplement threshold value of the second battery pack 120. When the state of charge of the second battery pack 120 is greater than the third threshold value, it is determined that the second battery pack 120 has sufficient power to supplement energy.

[0122] In some examples, the third threshold value can be in the range of 20%-50%, for example, 20%, 30%, 40% or 50%. In some examples, since the rated capacity of the second battery pack 120 is smaller, the third threshold value can be set to be greater than the second threshold value.

[0123] In some embodiments, when the main control system detects that the state of charge of the first battery pack 110 is as low as the second threshold value, and determines that the load still needs to be powered continuously, for example, the vehicle is driving, the main control system controls the bidirectional converter 130 to convert the power of the second battery pack 120 into a voltage suitable for the first battery pack 110, thereby supplementing the power of the first battery pack 110 and improving the endurance of the first battery pack 110.

[0124] In another embodiment, if the main control system determines that the load can tolerate a short switching of the power supply subject, the main control system can also control the bidirectional converter 130 to convert the voltage of the second battery pack 120 into a voltage suitable for the load, and disconnect the discharging switch of the first battery pack 110, thereby switching the power supply subject from the first battery pack 110 to the second battery pack 120.

[0125] Specifically, whether the second battery pack 120 is controlled to supplement the power of the first battery pack 110 or to switch the power supply subject can be selected according to the specific power consumption scenario, and the embodiments of the present application do not limit this.

[0126] The embodiments of the present application can reduce the risk of over-discharging of the first battery pack 110 by supplementing the power of the first battery pack 110 or switching the power supply subject, improve the continuity of the battery power supply externally, and be beneficial to prolong the service life of the battery, flexibly cope with different power consumption demands, and improve the energy utilization efficiency.

[0127] According to some embodiments of the present application, the battery is applied to a vehicle, and the two battery packs are respectively a first battery pack and a second battery pack; the main control system is further configured to: In the discharging phase, in response to the difference between the state parameter of the first battery pack and the state parameter of the second battery pack being less than or equal to a first threshold value, the driving state of the vehicle is obtained; the driving state includes an intelligent driving mode, a commuting mode or a long-distance mode; in response to the vehicle being in the smart driving mode, controlling the state of charge of the second battery pack to be greater than or equal to a fourth threshold value; in response to the vehicle being in the commuting mode, controlling the first battery pack to discharge externally until the state of charge of the first battery pack is less than or equal to a second threshold value, and switching to the second battery pack to discharge externally; and, in response to the vehicle being in the long-distance mode, controlling the first battery pack and the second battery pack to jointly discharge externally according to a ratio of the remaining charges of the two battery packs.

[0128] The rated capacity of the first battery pack is greater than the rated capacity of the second battery pack.

[0129] The driving state refers to the driving mode in which the vehicle is currently located. The driving state can be obtained through communication interaction between the main control system and the vehicle controller.

[0130] The smart driving mode refers to a driving state in which the vehicle is in a state of maximum intelligent auxiliary intervention and reduced driving operation intensity. In this mode, the battery prioritizes power supply for the intelligent system. The second battery pack 120 has a low discharge priority, and the probability of completely emptying its power is low. Controlling the state of charge of the second battery pack 120 to be greater than or equal to a fourth threshold value can serve as a power supply redundancy for the intelligent system, reducing the risk of sudden power failure causing malfunctions or accidents, and improving the reliability of vehicle travel.

[0131] The commuting mode refers to a state in which the vehicle is in a short-distance travel state in an urban area. In this mode, the vehicle is in a state of moderate maximum driving speed (≤80 km / h) and frequent start-stop, and the power supply continuity requirement is not high. The power supply main body can be switched smoothly during parking gaps or low-speed driving to achieve higher endurance.

[0132] The long-distance mode refers to a state in which the vehicle is in a continuous high-speed driving state. In this mode, the vehicle needs to continuously output a large current from the battery, and a single battery pack may not be able to meet the power demand. The main control system allocates the discharge current according to the ratio of the current remaining charges (usually in Ah or SOC) of the first battery pack 110 and the second battery pack 120, so that the two battery packs discharge synchronously according to the "electricity consumption ratio", and all the electricity in the two battery packs is discharged at the end of the discharge. This maximizes the use of the total electricity of the two battery packs and improves energy utilization efficiency.

[0133] Controlling the discharge mode of the battery pack according to different driving states can meet more diversified power demand and improve the energy utilization efficiency of the battery.

[0134] According to some embodiments of the present application, the main control system is further configured to: in the charging phase, charge the two battery packs according to the priority from high to low; and in response to the charging power exceeding the demand power of the battery pack with higher priority among the two battery packs, use the part of the charging power exceeding the demand power to charge the battery pack with lower priority among the two battery packs.

[0135] The charging power refers to the total power of the electric energy that can be provided by an external charging device (such as a charging pile or a vehicle-mounted charger) to the battery system, and is measured in kilowatts (kW), which is the total input capacity in the charging process.

[0136] The demand power refers to the maximum charging power that can be safely accepted by the battery pack (usually the battery pack with higher priority) that is currently being charged under the current state, which is the maximum input upper limit of the battery pack. In some examples, the lower the SOC of the battery pack, the greater the demand power, and vice versa.

[0137] In the charging phase, the main control system formulates a corresponding charging scheme according to the size of the charging power and the demand power of the battery pack with higher priority. For example, when the charging power is less than or equal to the demand power, the charging power is provided to the battery pack with higher priority for charging. When the charging power is greater than the demand power, the main control system splits the charging power, and when the demand power of the battery pack with higher priority is met, the part of the charging power exceeding the demand power is converted into a voltage suitable for the battery pack with lower priority by the bidirectional converter 130, so that the battery pack with lower priority is also charged synchronously.

[0138] In some embodiments, the part of the charging power exceeding the demand power can also exceed the demand power of the battery pack with lower priority, and the part of the excess power can be actively reduced by the external charging device to avoid overload.

[0139] The embodiments of the present application can further optimize the charging control logic by combining the relationship between the charging power and the demand power on the basis of determining the charging sequence based on the priority, thereby improving the charging efficiency of the battery.

[0140] According to some embodiments of the present application, the main control system is further configured to: in the discharging phase, in response to a failure of one of the two battery packs, control the other of the two battery packs to discharge externally.

[0141] When one of the battery packs fails, the main control system can adjust the voltage of the other battery pack to a voltage value suitable for the load through the bidirectional converter 130, so that the load can continue to be powered.

[0142] In the embodiments of the present application, the two battery packs can be redundant backups for each other, which can improve the continuity and reliability of battery power supply.

[0143] As Figure 6 shown in the above embodiments, the application provides a battery control method 400 applied to a battery 100. The battery includes two battery packs and a battery management system, the two battery packs are connected through a bidirectional converter, the battery management system is in signal connection with the bidirectional converter, and the battery management system includes two sub-battery management systems.

[0144] The battery control method 400 includes: Step S410, determining one of the two sub-battery management systems 160 as a master control system and the other as a slave control system; Step S420, the master control system acquires state parameters of the two battery packs, the state parameters being used to represent the health states of the battery packs; Step S430, the master control system sets the priority of the battery pack corresponding to the state parameter with a larger value in the charging stage and / or the priority of the battery pack in the discharging stage to be higher than that of the other battery pack in response to the difference between the state parameters of the two battery packs being greater than a first threshold value.

[0145] The state parameter can be any parameter capable of representing the health state of the battery pack, such as voltage, voltage response speed, equalization current, equalization interval time, internal resistance, etc., which can reflect the capacity attenuation and internal resistance increase of the battery cell. Exemplarily, the state parameter can be the state of health (SOH) of the battery. Steps S410 to S430 can be performed by the battery management system in the above embodiments, and the execution manner can refer to the related description of the above embodiments, which will not be described here.

[0146] The first threshold value can be determined according to the capacity attenuation characteristics, power demand, detection accuracy of the battery management system, etc. of the two battery packs.

[0147] The greater the state parameter, the better the health state of the battery, and vice versa. Exemplarily, the state parameter is the SOH of the corresponding battery pack. The greater the difference between the SOHs of the two battery packs, the greater the difference in aging degree between them. By adjusting the charging priority and / or discharging priority of the battery pack with a higher SOH, the battery with a good health state can participate more in the charging and discharging process, and the battery with a poor health state can slow down the aging speed, so that the aging difference between the two battery packs gradually decreases.

[0148] When the difference between the state parameters exceeds the first threshold value, the adjustment of the charging and discharging priority is triggered, which can better control the aging difference between the two battery packs and thus improve the overall performance of the battery.

[0149] It should be noted that the battery in the embodiment of the present application can also contain more battery groups, and the battery control method described in the embodiment can be implemented for any two battery groups in the battery, so as to determine the priority order between the multiple battery groups.

[0150] In some embodiments, the priority of the single battery group charging stage and the priority of the discharging stage are adjusted synchronously, that is, the priority of charging is also the priority of discharging, which is more conducive to the complete regulation of the cycle number of the battery group.

[0151] It can be understood that the battery control method of the embodiment of the present application can be implemented periodically or aperiodically in the whole life cycle of the battery, for example, the charging priority and the discharging priority of the battery group can be automatically executed and adjusted periodically after setting a time interval, or can be dynamically executed in real time according to the change of SOH.

[0152] It should be noted that the battery in the embodiment of the present application can also contain more battery groups, and the battery control method described in the embodiment can be implemented for any two battery groups in the battery, so as to determine the priority order between the multiple battery groups.

[0153] Two sub-battery management systems 160 are set, one of which is a master control system, and the master control system evaluates the aging difference of the battery groups by comparing the state parameters of the two battery groups, and triggers the adjustment of the charging and discharging priority when the difference of the state parameters exceeds the first threshold, and then adjusts the charging and discharging priority of the battery groups according to the aging difference, which can coordinate and balance the aging degree of the battery groups, prevent the aging difference from expanding, and is conducive to improving the service life of the whole battery and flexibly meeting diversified power demand. And the redundant design of the sub-battery management system 160 makes the remaining sub-battery management system continue to work normally as the master control system when the master control system fails, so as to more reliably meet the diversified power demand.

[0154] Reference Figure 3 According to some embodiments of the present application, the two battery groups are connected one by one with the two sub-battery management systems 160, and step S420 can include: The master control system and the slave control system respectively calculate the state parameters of the battery groups connected thereto; The slave control system sends the state parameters of the battery group connected thereto to the master control system.

[0155] The execution method of the above steps can refer to the related description above, which will not be repeated here.

[0156] In the technical solution, the state parameters of the two battery packs are calculated by the master control system and the slave control system respectively, so that each sub battery management system 160 is responsible for data collection of one battery pack, without time-sharing multiplexing of sampling channels, and the accuracy of calculation of the state parameters of the battery packs can be improved. The state parameters of the battery pack connected to the slave control system are sent to the master control system for summarization, and the master control system arbitrates the priorities of the two battery packs in the charging stage / discharge stage based on the state parameters of the two battery packs, so that the sub battery management system 160 normally connected to the bidirectional converter can be used as the master control system, and the sub battery management system 160 abnormally connected to the bidirectional converter can be used as the slave control system, and the redundancy design is realized.

[0157] Reference Figure 5 According to some embodiments of the present application, the two battery packs are connected to each sub battery management system 160, and step S420 can also include: In response to no failure of the two sub battery management systems 160, the master control system and the slave control system calculate the state parameters of different battery packs respectively, and the slave control system sends the calculated state parameters of the battery pack to the master control system; In response to failure of one of the two sub battery management systems 160, the sub battery management system 160 without failure is used as the master control system to calculate the state parameters of the two battery packs.

[0158] The execution method of the above steps can refer to the related description above, which will not be repeated here.

[0159] In the technical solution, if one of the two sub battery management systems 160 fails, the other sub battery management system 160 can be used as the master control system to control the change of the charging or discharging mode of the two battery packs. When neither of the two sub battery management systems 160 fails, the sampling mode of the two sub battery management systems 160 can also be adjusted according to different needs, so that the diversified power demand can be met more flexibly and reliably.

[0160] According to some embodiments of the present application, step S410 can include: determining the rated capacity of the two battery packs; In response to no failure of the two sub battery management systems 160, in the case that the rated capacities of the two battery packs are different, the sub battery management system 160 controlling the battery pack with larger rated capacity is used as the master control system, and the sub battery management system 160 controlling the other battery pack is used as the slave control system; In response to failure of one of the two sub battery management systems 160, the sub battery management system 160 without failure is used as the master control system, and the sub battery management system 160 with failure is used as the slave control system.

[0161] When both of the two sub battery management systems 160 do not fail, the battery pack with larger rated capacity is used more frequently than the battery pack with smaller rated capacity, and therefore the sub battery management system 160 that controls the battery pack with larger rated capacity is used more frequently, and therefore the sub battery management system 160 that controls the battery pack with larger rated capacity is taken as the master control system. The sub battery management system 160 that controls the battery pack here refers to the sub battery management system 160 that performs state monitoring, charge and discharge control, safety protection, and battery state evaluation on the battery pack it controls.

[0162] When both of the two sub battery management systems 160 do not fail, the sub battery management system 160 that does not fail is taken as the master control system, and the sub battery management system 160 that fails is taken as the slave control system, so as to realize redundancy design and ensure smooth charge and discharge of the battery.

[0163] In the technical solution, the sub battery management system 160 that controls the battery pack with larger rated capacity is taken as the master control system, so as to reduce the use of another slave control system, reduce waste of resources, take the sub battery management system 160 that does not fail as the master control system, realize redundancy design, and ensure smooth charge and discharge of the battery.

[0164] According to some embodiments of the present application, step S410 can also include: determining the rated cycle times of the two battery packs; When both of the two sub battery management systems 160 do not fail, in the case that the rated cycle times of the two battery packs are different, the sub battery management system 160 that controls the battery pack with more rated cycle times is taken as the master control system, and the sub battery management system 160 that controls the other battery pack is taken as the slave control system. When one of the two sub battery management systems 160 fails, the sub battery management system 160 that does not fail is taken as the master control system, and the sub battery management system 160 that fails is taken as the slave control system.

[0165] When both of the two sub battery management systems 160 do not fail, the battery pack with larger rated cycle times is used more frequently than the battery pack with smaller rated cycle times, and therefore the sub battery management system 160 that controls the battery pack with larger rated cycle times is used more frequently, and therefore the sub battery management system 160 that controls the battery pack with larger rated cycle times is taken as the master control system.

[0166] When neither of the two sub-battery management systems 160 fails, the battery pack with a larger number of rated cycles is used more frequently than the battery pack with a smaller number of rated cycles, and therefore, the sub-battery management system 160 that controls the battery pack with a larger number of rated cycles is used more frequently, and therefore, the sub-battery management system 160 that controls the battery pack with a larger number of rated cycles is used as the master control system. By using the sub-battery management system 160 that controls the battery pack with a larger number of rated cycles as the master control system, the use of another slave control system can be reduced, and resource waste can be reduced. By using the sub-battery management system 160 that does not fail as the master control system, a redundant design is achieved, and the smooth charging and discharging of the battery is ensured.

[0167] According to some embodiments of the present application, the method can further include: The master control system determines the priority of the two battery packs in the charging phase and / or the priority of the two battery packs in the discharging phase according to the rated capacity of the two battery packs in response to the difference between the state parameters of the two battery packs being less than or equal to the first threshold value.

[0168] When the difference between the state parameters of the two battery packs is less than or equal to the first threshold value, it means that the aging degrees of the two battery packs are close, and if the priority is still frequently adjusted at this time, the computing power consumption of the battery management system and the energy loss of the bidirectional converter will be increased. At this time, the priority of charging and discharging can be determined according to the size of the rated capacity of the two battery packs.

[0169] The rated capacities of the two battery packs are different. In some examples, the electrode assemblies of the battery cells in the two battery packs can adopt different chemical systems, for example, can be lithium iron phosphate systems and ternary systems respectively. The difference in such chemical systems can cause the rated capacities of the battery packs to be different. In other examples, the two battery packs can also respectively include different numbers of battery cells or battery modules, which can also make the rated capacities of the two battery packs different. Selecting battery packs with different rated capacities can flexibly select appropriate power supply sources according to power demand, thereby meeting diversified power demand.

[0170] The manner in which the master control system obtains the rated capacities of the two battery packs can refer to the related description in the above embodiments, which will not be described here.

[0171] When the state parameters are close, adjusting the charging and discharging priority according to the size of the rated capacity can better match the rated capacity and the power demand, and can maximize the advantages of battery packs with different capacities, thereby improving the overall performance of the battery.

[0172] According to some embodiments of the present application, in response to the difference between the state parameters of the two battery packs being less than or equal to the first threshold value, the master control system determines the priority of the two battery packs in the charging phase and / or the priority of the two battery packs in the discharging phase according to the rated capacity of the two battery packs, including: In response to the difference between the state parameters of the two battery packs being less than or equal to the first threshold value, the priority of the battery pack with the larger rated capacity in the charging stage and / or the priority of the battery pack with the larger rated capacity in the discharging stage is set to be higher than the battery pack with the smaller rated capacity.

[0173] The implementation method of the above steps can refer to the related description above, and will not be repeated here.

[0174] Setting the charging priority or discharging priority of the battery pack with the larger rated capacity to be higher can make the large-capacity battery reasonably bear the load, play its capacity and cycle performance advantages, reduce the risk of over-discharge of the small-capacity battery pack, and be beneficial to realize the synchronous attenuation of the two, and improve the overall performance of the battery.

[0175] According to some embodiments of the present application, the two battery packs are respectively a first battery pack 110 and a second battery pack 120; the method further comprises: In the discharging stage, the main control system acquires the state of charge of the first battery pack 110 in response to the difference between the state parameters of the first battery pack 110 and the second battery pack 120 being less than or equal to the first threshold value. The main control system controls the first battery pack 110 to preferentially discharge to the outside in response to the state of charge of the first battery pack 110 being greater than a second threshold value, until the state of charge of the first battery pack 110 is less than or equal to the second threshold value.

[0176] The rated capacity of the first battery pack 110 is greater than the rated capacity of the second battery pack 120.

[0177] When the SOC of the first battery pack 110 is greater than the second threshold value, it means that the first battery pack 110 with the larger rated capacity has relatively sufficient electric energy, and the first battery pack 110 is preferentially controlled to supply power to the load when discharging. When the SOC of the first battery pack is lower than the second threshold value, the battery pack that preferentially supplies power can be switched to reduce the risk of over-discharge of the first battery pack.

[0178] The large-capacity battery not only has more stored electricity, but also has the advantages of strong cycle tolerance and stable output power. When the large-capacity battery has sufficient electric energy, it is preferentially used to supply power, which can reduce the switching frequency of the bidirectional converter 130, reduce the capacity conversion loss, and reduce the failure probability of the small-capacity battery.

[0179] According to some embodiments of the present application, the method further comprises: In the discharging stage, the main control system controls the second battery pack 120 to charge the first battery pack 110 that is discharging, or switches the second battery pack 120 to discharge to the outside in response to the state of charge of the first battery pack 110 being less than or equal to the second threshold value and the state of charge of the second battery pack 120 being greater than a third threshold value.

[0180] The third threshold is a power compensation threshold of the second battery pack 120, and when the SOC of the second battery pack 120 is greater than the third threshold, it is determined that the second battery pack 120 has sufficient power to compensate.

[0181] In some examples, the third threshold can be in a range of 20%-50%, for example, 20%, 30%, 40% or 50%. In some examples, the third threshold can be set to be greater than the second threshold due to the smaller rated capacity of the second battery pack 120.

[0182] The SOC of the first battery pack 110 being less than or equal to the second threshold and the SOC of the second battery pack 120 being greater than the third threshold means that the first battery pack 110 has insufficient remaining power, while the second battery pack 120 has relatively sufficient power, and at this time the second battery pack 120 can be used as a power compensation source or a backup power source.

[0183] The second battery pack 120 can compensate the first battery pack 110 by supplying power to the first battery pack 110, and at this time the priority of the first battery pack 110 for discharging externally is still higher than that of the second battery pack 120. The second battery pack 120 can also directly replace the first battery pack 110 to discharge externally, and at this time the discharging priority of the second battery pack 120 is higher than that of the first battery pack 110.

[0184] The embodiments of the present application can reduce the risk of over-discharge of the first battery pack 110 by compensating the first battery pack 110 or switching the power supply subject, improve the continuity of the battery external power supply, and be beneficial to prolong the service life of the battery, flexibly cope with different power consumption demands, and improve the energy utilization efficiency.

[0185] According to some embodiments of the present application, the battery is applied to a vehicle, and the two battery packs are the first battery pack 110 and the second battery pack 120, and the rated capacity of the first battery pack 110 is greater than that of the second battery pack 120; the method further comprises: In the discharging phase, the main control system acquires the driving state of the vehicle in response to the difference between the state parameters of the first battery pack 110 and the state parameters of the second battery pack 120 being less than or equal to the first threshold; the driving state includes an intelligent driving mode, a commuting mode or a long-distance mode; The main control system controls the state of charge of the second battery pack to be greater than or equal to the fourth threshold in response to the vehicle being in the intelligent driving mode; The main control system controls the first battery pack 110 to discharge externally until the SOC of the first battery pack 110 is less than or equal to the second threshold, and switches to the second battery pack 120 to discharge externally in response to the vehicle being in the commuting mode; and The main control system controls the first battery pack 110 and the second battery pack 120 to discharge externally according to the ratio of the remaining charges of the two battery packs in response to the vehicle being in the long-distance mode.

[0186] The execution method of the above steps can refer to the related description above, which will not be repeated here.

[0187] According to the control of the discharging mode of the battery pack according to different driving states, more diversified power consumption demands can be met, and the energy utilization efficiency of the battery can be improved.

[0188] According to some embodiments of the application, the method further comprises: In the charging phase, the main control system charges the two battery packs according to the priority from high to low; In response to the charging power exceeding the demand power of the battery pack with higher priority in the two battery packs, the main control system uses the part of the charging power exceeding the demand power to charge the battery pack with lower priority in the two battery packs.

[0189] The execution method of the above steps can refer to the related description above, which will not be repeated here.

[0190] The embodiments of the application can further optimize the charging control logic by combining the relationship between the charging power and the demand power on the basis of determining the charging sequence based on the priority, thereby improving the charging efficiency of the battery.

[0191] According to some embodiments of the application, the method further comprises: In the discharging phase, in response to a failure of one of the two battery packs, the main control system controls the other of the two battery packs to discharge externally.

[0192] When one of the battery packs fails, the main control system can adjust the voltage of the other battery pack to a voltage value suitable for the load through the bidirectional converter 130, so that the load can continue to be powered.

[0193] In the embodiments of the application, the two battery packs can be redundant backups for each other, which can improve the continuity and reliability of the battery power supply.

[0194] Reference Figures 3 to 5 The embodiments of the third aspect of the application provide a battery comprising two battery packs, the two battery packs being connected through a bidirectional converter, and a battery management system connected with the bidirectional converter. The battery management system is the battery management system in the above embodiments, or the battery management system is used to execute the battery control method in the above embodiments.

[0195] The two battery packs are a first battery pack 110 and a second battery pack 120, the rated capacity of the first battery pack 110 is greater than the rated capacity of the second battery pack 120; and / or, the rated cycle number of the first battery pack 110 is greater than the rated cycle number of the second battery pack 120.

[0196] In some examples, the electrode assemblies of the individual cells in the first battery pack 110 and the second battery pack 120 may employ different chemical systems, such as lithium iron phosphate and ternary lithium batteries, respectively. This difference in chemical system may result in different rated capacities and / or rated cycle lives of the battery packs. For example, the first battery pack 110 may be a lithium-ion battery, and the second battery pack 120 may be a sodium-ion battery.

[0197] In other examples, the first battery pack 110 and the second battery pack 120 may also use the same chemical system, but they may contain different numbers of battery cells or battery modules, thus resulting in different rated capacities. Selecting battery pack combinations with different rated capacities and / or rated cycle counts allows for flexible selection of a suitable power source based on power demand, thereby meeting diverse power requirements.

[0198] By differentiating the rated capacity of the first battery pack 110 and the second battery pack 120, the battery's ability to meet diverse power needs and its cost can be balanced, which is conducive to improving the energy utilization efficiency of the battery.

[0199] like Figure 1 As shown, an embodiment of the third aspect of this application provides a vehicle 1000, which includes a battery 100 as described above, the battery 100 being used to provide electrical energy.

[0200] The vehicle 1000 of this application embodiment includes the battery 100 described in the above embodiments, and therefore also has the beneficial effects described in the foregoing embodiments, which will not be repeated here.

[0201] This application provides a computing device including: at least one processor; and at least one memory communicatively connected to the at least one processor, wherein the at least one memory stores instructions that, when executed individually or jointly by the at least one processor, cause the computing device to perform the battery control method 400 described in the above embodiments.

[0202] Various implementations of the systems and techniques described above can be realized in digital electronic circuitry, integrated circuitry, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a system on a chip (SoC), a programmable logic device (CPLD), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include implementation in one or more computer programs that are executable and / or interpretable on a programmable system including at least one programmable processor, which can be special or general purpose, coupled to receive data and instructions from, and to transmit data and instructions to, a storage system, at least one input device, and at least one output device.

[0203] An embodiment of the present application provides a computer readable storage medium storing instructions, which, when executed by one or more processors of a computing device, alone or in combination, cause the computing device to perform the battery control method 400 described in the above embodiments.

[0204] A computer readable medium can be a tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. The machine-readable medium can include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the above. More specific examples of the machine-readable storage medium will include one or more lines of electrical connections, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disc read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the above.

[0205] An embodiment of the present application provides a computer program product including instructions, which, when executed by one or more processors of a computing device, alone or in combination, cause the computing device to perform the battery control method 400 described in the above embodiments.

[0206] The technical solutions of the present application are further described below in combination with a specific embodiment.

[0207] As Figure 4As shown, the battery 100 is mounted on the vehicle 1000, and is used to provide electric energy for the vehicle 1000. The battery 100 comprises a first battery pack 110, a second battery pack 120, a bidirectional converter 130, a high-voltage power supply connection terminal 140, a charging connection terminal 150, and two sub-battery management systems 160, which are signal connected with the bidirectional converter.

[0208] The first battery pack 110 and the second battery pack 120 are connected through the bidirectional converter 130, and then connected with the high-voltage power supply connection terminal 140 and the charging connection terminal 150, wherein the high-voltage power supply connection terminal 140 is used to be connected with a load, and the charging connection terminal 150 is used to be connected with an external charging device.

[0209] The two sub-battery management systems 160 are respectively used to obtain state parameters of the first battery pack 110 and the second battery pack 120, and the two sub-battery management systems 160 are signal connected. Figure 7 As shown, the battery control method is as follows: Step S501, start.

[0210] Step S502, one of the two sub-battery management systems is used as a master control system, and the other is used as a slave control system. For example, when neither of the two battery management systems fails, the sub-battery management system controlling the first battery pack is used as the master control system, and the sub-battery management system controlling the second battery pack is used as the slave control system. When the connection between one of the two sub-battery management systems and the bidirectional converter fails, the sub-battery management system 160 connected normally with the bidirectional converter is used as the master control system, and the sub-battery management system 160 connected abnormally with the bidirectional converter is used as the slave control system.

[0211] Step S503, the master control system obtains the state parameter of the first battery pack 110. The state parameter is the SOH of the battery pack.

[0212] Step S504, the slave control system obtains the state parameter of the second battery pack 120.

[0213] Step S505, the slave control system sends the state parameter of the second battery pack 120 to the master control system.

[0214] Step S506, the master control system judges whether the difference between the state parameters of the first battery pack 110 and the second battery pack 120 is greater than X%, wherein X% is a first threshold. If yes, step S507 is executed, and if no, steps S503 and S504 are returned.

[0215] Step S507, the master control system judges whether the rated capacity of the first battery pack 110 is greater than the rated capacity of the second battery pack 120. If yes, step S508 is executed, and if no, step S509 is executed.

[0216] Step S508, the main control system sets the priority of the first battery pack 110 in the charging phase and the priority in the discharging phase to be higher than the second battery pack 120.

[0217] Step S509, the main control system sets the priority of the second battery pack 120 in the charging phase and the priority in the discharging phase to be higher than the first battery pack 110.

[0218] Step S510, end.

[0219] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the claims and the specification of the present application. In particular, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery management system, characterized in that, The battery management system is used to manage the battery packs in the battery, the battery including two battery packs connected by a bidirectional converter, and the battery management system includes: Two sub-battery management systems are signal-connected to the bidirectional converter, with one of the sub-battery management systems acting as the master control system and the other as the slave control system; wherein... The main control system is configured to: acquire state parameters of the two battery packs, and in response to the difference between the state parameters of the two battery packs being greater than a first threshold, set the priority of the battery pack with the larger state parameter in the charging phase and / or the priority in the discharging phase to be higher than that of the other battery pack, wherein the state parameters are used to characterize the health status of the battery packs.

2. The battery management system according to claim 1, characterized in that, The two sub-battery management systems are connected one-to-one with the two battery packs; wherein, The main control system and the slave control system are configured to calculate the state parameters of the battery pack connected thereto, respectively; the slave control system is also configured to send the state parameters of the battery pack connected thereto to the main control system.

3. The battery management system according to claim 1, characterized in that, Each of the sub-battery management systems is connected to both of the battery packs; wherein, In the absence of failure in the two sub-battery management systems, the main control system and the slave control system are configured to calculate the state parameters of different battery packs respectively, and the slave control system is further configured to send the calculated state parameters of the battery packs to the main control system. In the event of a failure in one of the two sub-battery management systems, the non-faulty sub-battery management system acts as the main control system to calculate the state parameters of the two battery packs.

4. The battery management system according to claim 1, characterized in that, The main control system is also configured to: In response to the difference in state parameters between the two battery packs being less than or equal to a first threshold, the priority of the two battery packs during the charging phase and / or the priority during the discharging phase is determined based on the rated capacity of the two battery packs.

5. The battery management system according to claim 4, characterized in that, The main control system is also configured to: In response to the difference in state parameters between the two battery packs being less than or equal to a first threshold, the battery pack with the larger rated capacity is given a higher priority during the charging phase and / or the discharge phase than the battery pack with the smaller rated capacity.

6. The battery management system according to any one of claims 1-5, characterized in that, The two sub-battery management systems are configured such that when one of them fails, the other acts as the main control system to control the discharge or charging of the two battery packs.

7. The battery management system according to any one of claims 1-5, characterized in that, The two battery packs are designated as a first battery pack and a second battery pack, and the main control system is further configured to: During the discharge phase, the state of charge of the first battery pack is obtained in response to the difference between the state parameters of the first battery pack and the state parameters of the second battery pack being less than or equal to a first threshold. as well as, In response to the first battery pack having a state of charge greater than a second threshold, the first battery pack is controlled to discharge externally preferentially until the state of charge of the first battery pack is less than or equal to the second threshold.

8. The battery management system according to claim 7, characterized in that, The main control system is also configured to: During the discharge phase, in response to the first battery pack's state of charge being less than or equal to the second threshold and the second battery pack's state of charge being greater than the third threshold, the second battery pack is controlled to charge the first battery pack that is discharging, or the second battery pack is switched to discharge externally.

9. The battery management system according to any one of claims 1-5, characterized in that, The battery is used in a vehicle, and the two battery packs are a first battery pack and a second battery pack, respectively. The main control system is also configured to: During the discharge phase, in response to the difference between the state parameters of the first battery pack and the state parameters of the second battery pack being less than or equal to a first threshold, the driving state of the vehicle is obtained; the driving state includes intelligent driving mode, commuting mode or long-distance mode. In response to the vehicle being in the intelligent driving mode, the state of charge of the second battery pack is controlled to be greater than or equal to a fourth threshold. In response to the vehicle being in the commuting mode, the first battery pack is controlled to discharge externally until the state of charge of the first battery pack is less than or equal to a second threshold, at which point the second battery pack switches to discharging externally; and... In response to the vehicle being in the long-distance mode, the first battery pack and the second battery pack are controlled to discharge together according to the ratio of their remaining charge.

10. The battery management system according to any one of claims 1-5, characterized in that, The main control system is also configured to: During the charging phase, the two battery packs are charged according to their priority from high to low; and, In response to a charging power exceeding the power requirement of the higher-priority battery pack among the two battery packs, the portion of the charging power exceeding the power requirement is used to charge the lower-priority battery pack among the two battery packs.

11. The battery management system according to any one of claims 1-5, characterized in that, The main control system is also configured to: During the discharge phase, in response to a fault in one of the two battery packs, the other of the two battery packs is controlled to discharge externally.

12. A battery control method, applied to a battery, characterized in that, The battery includes two battery packs and a battery management system. The two battery packs are connected via a bidirectional converter, and the battery management system is signal-connected to the bidirectional converter. The battery management system includes two sub-battery management systems. The method includes: One of the two sub-battery management systems is designated as the master control system, and the other as the slave control system. The main control system acquires the status parameters of the two battery packs, and the status parameters are used to characterize the health status of the battery packs. The main control system responds when the difference between the state parameters of the two battery packs is greater than a first threshold, by setting the priority of the battery pack with the larger state parameter during the charging phase and / or the discharge phase to be higher than that of the other battery pack.

13. The method according to claim 12, characterized in that, The two battery packs are connected one-to-one with the two sub-battery management systems. The main control system acquires the status parameters of the two battery packs, including: The main control system and the slave control system respectively calculate the state parameters of the battery pack connected to them; The slave control system sends the status parameters of the battery pack connected to it to the master control system.

14. The method according to claim 12, characterized in that, Both battery packs are connected to each of the sub-battery management systems. The main control system acquires the status parameters of the two battery packs, including: In response to the absence of faults in the two sub-battery management systems, the main control system and the slave control system respectively calculate the state parameters of different battery packs, and the slave control system sends the calculated state parameters of the battery packs to the main control system; In response to a failure in one of the two sub-battery management systems, the non-faulty sub-battery management system acts as the main control system to calculate the state parameters of the two battery packs.

15. The method according to claim 12, characterized in that, The determination of one of the two sub-battery management systems as a master control system and the other as a slave control system includes: Determine the rated capacity of the two battery packs; In response to the absence of failure in both sub-battery management systems, when the rated capacities of the two battery packs are different, the sub-battery management system controlling the battery pack with the larger rated capacity shall be used as the main control system, and the sub-battery management system controlling the other battery pack shall be used as the slave control system. In response to a failure in one of the two sub-battery management systems, the non-failed sub-battery management system is designated as the master control system, and the failed sub-battery management system is designated as the slave control system.

16. The method according to claim 12, characterized in that, The determination of one of the two sub-battery management systems as a master control system and the other as a slave control system includes: Determine the rated number of cycles for the two battery packs; In response to the absence of failure in both sub-battery management systems, when the rated cycle counts of the two battery packs are different, the sub-battery management system controlling the battery pack with the higher rated cycle count is designated as the master control system, and the sub-battery management system controlling the other battery pack is designated as the slave control system. In response to a failure in one of the two sub-battery management systems, the non-failed sub-battery management system is designated as the master control system, and the failed sub-battery management system is designated as the slave control system.

17. The method according to claim 12, characterized in that, The method further includes: The main control system responds to the fact that the difference between the state parameters of the two battery packs is less than or equal to a first threshold, and determines the priority of the two battery packs in the charging phase and / or the priority in the discharging phase according to the rated capacity of the two battery packs.

18. The method according to claim 17, characterized in that, The main control system responds to the condition that the difference in state parameters between the two battery packs is less than or equal to a first threshold, and determines the priority of the two battery packs during the charging phase and / or discharging phase based on their rated capacity, including: In response to the difference in state parameters between the two battery packs being less than or equal to a first threshold, the battery pack with the larger rated capacity is given a higher priority during the charging phase and / or the discharge phase than the battery pack with the smaller rated capacity.

19. The method according to any one of claims 12 to 18, characterized in that, The two battery packs are referred to as the first battery pack and the second battery pack, respectively. The method further includes: During the discharge phase, the main control system responds to the difference between the state parameters of the first battery pack and the state parameters of the second battery pack being less than or equal to a first threshold, and obtains the state of charge of the first battery pack. The main control system responds to the first battery pack's state of charge being greater than the second threshold by controlling the first battery pack to discharge externally preferentially until the first battery pack's state of charge is less than or equal to the second threshold.

20. The method according to claim 19, characterized in that, The method further includes: During the discharge phase, the main control system responds to the first battery pack's state of charge being less than or equal to the second threshold and the second battery pack's state of charge being greater than the third threshold by controlling the second battery pack to charge the first battery pack that is discharging, or by switching to the second battery pack discharging externally.

21. The method according to any one of claims 12 to 18, characterized in that, The battery is used in a vehicle, and the two battery packs are a first battery pack and a second battery pack, respectively. The method further includes: During the discharge phase, the main control system responds to the difference between the state parameters of the first battery pack and the state parameters of the second battery pack being less than or equal to a first threshold, and obtains the driving status of the vehicle; the driving status includes intelligent driving mode, commuting mode or long-distance mode; The main control system responds to the vehicle being in the intelligent driving mode by controlling the state of charge of the second battery pack to be greater than or equal to the fourth threshold. The main control system, in response to the vehicle being in the commuting mode, controls the first battery pack to discharge externally until the state of charge of the first battery pack is less than or equal to a second threshold, then switches to the second battery pack discharging externally; and The main control system responds to the vehicle being in the long-distance mode by controlling the first battery pack and the second battery pack to discharge together according to the ratio of their remaining charge.

22. The method according to any one of claims 12 to 18, characterized in that, The method further includes: During the charging phase, the main control system charges the two battery packs from high to low according to the priority. The main control system responds to a situation where the charging power exceeds the power requirement of the higher-priority battery pack among the two battery packs by using the portion of the charging power exceeding the power requirement to charge the lower-priority battery pack among the two battery packs.

23. The method according to any one of claims 12 to 18, characterized in that, The method further includes: During the discharge phase, the main control system responds to a fault in one of the two battery packs by controlling the other of the two battery packs to discharge externally.

24. A battery, characterized in that, include: Two battery packs are connected via a bidirectional converter, and A battery management system for managing the battery pack, wherein the battery management system is the battery management system according to any one of claims 1-11, or the battery management system is used to execute the battery control method according to any one of claims 12-23.

25. A vehicle, characterized in that, The vehicle includes the battery as described in claim 24, the battery being used to provide electrical energy.

26. A computing device, characterized in that, include: At least one processor; as well as At least one memory communicatively connected to the at least one processor, the at least one memory storing instructions that, when executed individually or jointly by the at least one processor, cause the computing device to perform the method of any one of claims 12 to 23.

27. A computer-readable storage medium, characterized in that, The device stores instructions that, when executed individually or jointly by one or more processors of the computing device, cause the computing device to perform the method of any one of claims 12 to 23.

28. A computer program product, characterized in that, Includes instructions that, when executed individually or jointly by one or more processors of a computing device, cause the computing device to perform the method of any one of claims 12 to 23.

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