Battery energy state determination method, battery management system, device and storage medium

Abstract

The present application relates to a battery energy state determination method, battery management system, device, and storage medium. The method includes: determining at least one target battery pack branch from multiple battery pack branches based on the branch states of multiple battery pack branches in a battery module, so as to determine the energy state of the battery module based on the charge state of the at least one target battery pack branch; the at least one target battery pack branch includes at least one battery pack branch that is not connected to the energy transmission system of the battery module; in the above method, the selected target battery pack branches include battery pack branches that can subsequently be connected to the energy transmission system, which can adapt to the actual situation that the battery pack branches in the battery module are connected to the energy transmission system one by one, so that the selected target battery pack branches are battery pack branches that can actually participate in energy transmission in the future, which can be used to accurately measure the actual available energy of the battery module, thereby improving the accuracy of the obtained energy state of the battery module.

Description

Technical Field

[0001] The present application relates to the field of battery management technology, and in particular to a battery energy status determination method, a battery management system, a device, and a storage medium. Background Art

[0002] With the development of new energy technologies, batteries are increasingly being used in various industries.

[0003] Taking new energy vehicles as an example, they typically use battery modules consisting of multiple parallel battery pack branches as their power source, and exchange energy with other devices through an energy transmission system. In related technologies, the Battery Management System (BMS) estimates the battery module's State of Energy (SOE) based on the battery pack branches within the battery module that are connected to the energy transmission system, thereby enabling monitoring and management of the battery module.

[0004] However, the accuracy of energy state estimation of battery modules in related technologies is relatively poor. Summary of the Invention

[0005] Based on this, it is necessary to provide a battery energy status determination method, battery management system, device and storage medium to address the above technical problems.

[0006] In a first aspect, an embodiment of the present application provides a method for determining a battery energy state, the method comprising:

[0007] determining at least one target battery pack branch from the plurality of battery pack branches according to branch states of the plurality of battery pack branches in the battery module; the at least one target battery pack branch including at least one battery pack branch that is not connected to an energy transmission system of the battery module;

[0008] The energy state of the battery module is determined according to the remaining power of at least one target battery pack branch.

[0009] In an embodiment of the present application, a target battery pack branch screened out from the battery module is used to determine the energy state of the battery module, and the screened out target battery pack branch includes a battery pack branch that can be subsequently connected to the energy transmission system, which can adapt to the actual situation that the battery pack branches in the battery module are connected to the energy transmission system one by one, so that the screened out target battery pack branch is the battery pack branch that can actually participate in energy transmission subsequently, which can be used to accurately measure the actual available energy of the battery module, thereby improving the accuracy of the obtained energy state of the battery module.

[0010] In one embodiment, determining at least one target battery pack branch from the plurality of battery pack branches based on branch states of the plurality of battery pack branches in the battery module includes:

[0011] Determining multiple candidate battery pack branches from the multiple battery pack branches according to branch states of the multiple battery pack branches in the battery module;

[0012] At least one target battery pack branch is determined from the plurality of candidate battery pack branches according to the connection status of each candidate battery pack branch and the energy transmission system.

[0013] In an embodiment of the present application, candidate battery pack branches are screened from the battery module based on the branch status, and target battery pack branches are screened from the candidate battery pack branches based on the connection status. The influence of the branch status and the connection status on the screening of the target battery pack branches is taken into account, thereby improving the accuracy of the obtained target battery pack branch.

[0014] In one embodiment, determining at least one target battery pack branch from a plurality of candidate battery pack branches based on the connection status of each candidate battery pack branch and the energy transmission system includes:

[0015] Determining at least one first branch that is connected to the energy transmission system and at least one second branch that is not connected to the energy transmission system from a plurality of candidate battery pack branches;

[0016] At least one target battery pack branch is determined from a plurality of candidate battery pack branches according to the voltages of at least one first branch and at least one second branch, and an energy transmission mode of the battery module.

[0017] In an embodiment of the present application, the energy transmission mode of the battery module and the voltage of the candidate battery pack branch in different connection states will affect whether the candidate battery pack branch that is not connected to the energy transmission system can be normally connected under future working conditions. Therefore, by utilizing the energy transmission mode of the battery module and the voltage of the candidate battery pack branch in different connection states, the target battery pack branch is determined from the candidate battery pack branches, and the reliability of the determined target battery pack branch can be improved.

[0018] In one embodiment, determining at least one target battery pack branch from a plurality of candidate battery pack branches based on the voltages of at least one first branch and at least one second branch, and an energy transfer mode of the battery module, includes:

[0019] Determining a branch with a maximum voltage in at least one first branch according to the energy transmission mode of the battery module and the voltages of the first branches;

[0020] At least one target battery pack branch is determined from a plurality of candidate battery pack branches according to the voltage of the maximum voltage branch and the voltage of at least one second branch.

[0021] In an embodiment of the present application, the branch with the maximum voltage is determined in the first branch based on the energy transmission mode, and the target battery pack branch is determined from the candidate battery pack branches according to the voltage of the branch with the maximum voltage and each second branch. This helps to eliminate the candidate battery pack branches that cannot be connected to the energy transmission system in the candidate battery pack branches through voltage comparison, thereby realizing rapid screening of the target battery pack branches and improving the overall efficiency of battery energy status determination.

[0022] In one embodiment, determining a branch with a maximum voltage in at least one first branch according to an energy transmission mode of the battery module and the voltages of the first branches includes:

[0023] When the energy transmission mode of the battery module is the discharge mode, determining a first branch with the smallest voltage among at least one first branch according to the voltages of the first branches as the maximum voltage branch;

[0024] When the energy transmission mode of the battery module is the charging mode, a first branch with the largest voltage is determined in at least one first branch according to the voltages of the first branches as the maximum voltage branch.

[0025] In an embodiment of the present application, in the discharge mode of the battery module, the first branch with the smallest voltage is adopted as the maximum voltage branch, and in the charging mode of the battery module, the first branch with the largest voltage is adopted as the maximum voltage branch, so as to clarify the maximum voltage branch adopted for screening the target battery pack branch under different working conditions of the battery module, improve the adaptability of the maximum voltage branch and the working state of the battery module, and thus improve the accuracy and reliability of the target battery pack branch obtained under different working conditions of the battery module.

[0026] In one embodiment, determining at least one target battery pack branch from a plurality of candidate battery pack branches based on the voltage of the maximum voltage branch and the voltage of at least one second branch includes:

[0027] Comparing the voltage of each second branch with the voltage of the maximum voltage branch to obtain a voltage magnitude relationship between each second branch and the maximum voltage branch;

[0028] At least one target battery pack branch is determined from a plurality of candidate battery pack branches based on the energy transmission mode of the battery module and the relationship between the voltages.

[0029] In an embodiment of the present application, the above-mentioned voltage magnitude relationship under different energy transmission modes can be used to estimate whether the second branch can be connected to the energy transmission system. The target battery pack branch is determined based on the above-mentioned voltage magnitude relationship and the energy transmission mode of the battery module, which can improve the reliability of the target battery pack branch obtained in successfully connecting to the energy transmission system and participating in energy interaction. The target battery pack branch that can participate in energy interaction is used to predict the energy state of the battery module, which correspondingly improves the accuracy of the energy state prediction.

[0030] In one embodiment, determining at least one target battery pack branch from a plurality of candidate battery pack branches based on the energy transfer mode of the battery module and the relationship between the voltages includes:

[0031] When the energy transmission mode of the battery module is the discharge mode and there is no second branch whose voltage is greater than the voltage of the maximum voltage branch in all voltage magnitude relationships, each candidate battery pack branch is used as the target battery pack branch;

[0032] When the energy transmission mode of the battery module is the discharge mode, and in all voltage magnitude relationships there is a second branch whose voltage is greater than the voltage of the maximum voltage branch, the second branch whose voltage is greater than the voltage of the maximum voltage branch is eliminated from multiple candidate battery pack branches to obtain at least one target battery pack branch.

[0033] In the embodiment of the present application, the specific method of determining the target battery pack branch in the discharge mode is clarified, and the conduction strategy of the battery pack branch and the energy transmission system in the discharge mode is adapted, thereby improving the reliability of the target battery pack branch in the discharge mode, and correspondingly improving the accuracy of the battery module energy state determined based on the reliable target battery pack branch.

[0034] In one embodiment, determining at least one target battery pack branch from a plurality of candidate battery pack branches based on the energy transfer mode of the battery module and the relationship between the voltages includes:

[0035] When the energy transmission mode of the battery module is the charging mode and there is no second branch whose voltage is less than the voltage of the maximum voltage branch in all voltage magnitude relationships, all candidate battery pack branches are used as target battery pack branches;

[0036] When the energy transmission mode of the battery module is the charging mode, and in all voltage magnitude relationships there is a second branch whose voltage is lower than the voltage of the maximum voltage branch, the second branch whose voltage is lower than the voltage of the maximum voltage branch is eliminated from multiple candidate battery pack branches to obtain at least one target battery pack branch.

[0037] In the embodiment of the present application, the specific method of determining the target battery pack branch in the charging mode is clarified, and the conduction strategy of the battery pack branch and the energy transmission system in the charging mode is adapted to improve the reliability of the target battery pack branch in the charging mode, and correspondingly improves the accuracy of the battery module energy state determined based on the reliable target battery pack branch.

[0038] In one embodiment, the method further includes:

[0039] When all target battery pack branches are connected to the energy transmission system and the energy transmission mode of the battery module is switched, obtaining at least one branch to be connected in the battery module that is not connected to the energy transmission system;

[0040] According to the target transmission mode switched to by the battery module and the voltage of at least one branch to be turned on, each branch to be turned on is turned on and connected to the energy transmission system.

[0041] In an embodiment of the present application, when the energy transmission mode of the battery module is switched, there is no need to disconnect the target battery packs that have been connected to the energy transmission system and then connect them again. The remaining branches to be connected can continue to be connected to the energy transmission system according to the target transmission mode, thereby improving the mode switching efficiency, reducing the switching loss of the mode switching, and extending the service life of the switch.

[0042] In one embodiment, according to the target transmission mode switched to by the battery module and the voltage of at least one branch to be turned on, each branch to be turned on is turned on with the energy transmission system, including:

[0043] Determining a conduction order for each branch to be conducted and the energy transmission system to be conducted according to a target transmission mode and a voltage of at least one branch to be conducted;

[0044] Each branch to be turned on is connected to the energy transmission system in turn according to the conduction sequence.

[0045] In an embodiment of the present application, the conduction sequence is determined based on the target transmission mode and the voltage of each branch to be turned on, so that each branch to be turned on is turned on with the energy transmission system in turn according to the conduction sequence, thereby achieving orderly conduction of each branch to be turned on and improving the stability of the battery module operation.

[0046] In one embodiment, determining a conduction order for each branch to be conducted and the energy transmission system to be conducted according to a target transmission mode and a voltage of at least one branch to be conducted includes:

[0047] When the target transmission mode is the discharge mode, the order of the voltages of the branches to be turned on from large to small is used as the turn-on order;

[0048] When the target transmission mode is the charging mode, the order of the voltages of the branches to be turned on from small to large is used as the turn-on order.

[0049] In the embodiments of the present application, the conduction sequence of the battery module under different energy transmission modes is clarified, which is adapted to different mode switches, thereby improving the stability of the battery module working mode switching and the stability of the operation after switching.

[0050] In one embodiment, the steps of sequentially connecting each branch to be connected to the energy transmission system according to a connection sequence include:

[0051] Prioritize the conduction of the pre-charge branch between the first branch to be conducted and the energy transmission system according to the conduction sequence;

[0052] When the voltage of the first branch to be turned on meets the voltage requirement of the target transmission mode, the first branch to be turned on is turned on to the energy transmission system, and the remaining branches to be turned on are turned on to the energy transmission system in sequence according to the turn-on order.

[0053] In an embodiment of the present application, the voltage of the branch to be conducted is changed by conducting a pre-stored branch between the branch to be conducted and the energy transmission system, so that the branch to be conducted can meet the voltage requirement under the corresponding target transmission mode, thereby improving the success rate of conduction between the branch to be conducted and the energy transmission system.

[0054] In one embodiment, the target transmission mode is a discharge mode, and the voltage requirements of the target transmission mode include: the voltage of the branch to be turned on is less than the voltage of the battery pack branch in the battery module that was last turned on with the energy transmission system, and the voltage difference is less than the first voltage difference.

[0055] In one embodiment, the target transmission mode is a charging mode, and the voltage requirements of the target transmission mode include: the voltage of the branch to be turned on is greater than the voltage of the battery pack branch in the battery module that was last turned on with the energy transmission system, and the voltage difference is greater than the second voltage difference.

[0056] In a second aspect, an embodiment of the present application further provides a device for determining a battery energy state, the device comprising:

[0057] a branch determination module, configured to determine at least one target battery pack branch from the plurality of battery pack branches based on branch states of the plurality of battery pack branches in the battery module; the at least one target battery pack branch including at least one battery pack branch that is not connected to the energy transmission system of the battery module;

[0058] The state estimation module is used to determine the energy state of the battery module based on the remaining power of at least one target battery pack branch.

[0059] In a third aspect, an embodiment of the present application further provides a battery management system comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps in the battery energy status determination method provided in any one of the embodiments of the first aspect are implemented.

[0060] In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the battery energy status determination method provided in any one of the embodiments of the first aspect above.

[0061] In a fifth aspect, an embodiment of the present application further provides a computer program product, comprising a computer program, which, when executed by a processor, implements the steps of the battery energy status determination method provided in any one of the embodiments of the first aspect above.

[0062] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 A schematic diagram of an application environment of a method for determining a battery energy state in one embodiment;

[0064] Figure 2 1 is a flow chart of a method for determining a battery energy state in one embodiment;

[0065] Figure 3 Schematic diagram of a process for determining a target battery pack branch in one embodiment;

[0066] Figure 4 is a schematic diagram of a flow chart for determining a target battery pack branch in another embodiment;

[0067] Figure 5 is a schematic diagram of a flow chart for determining a target battery pack branch in another embodiment;

[0068] Figure 6 1 is a schematic diagram of a flow chart for determining a branch with a maximum voltage value in one embodiment;

[0069] Figure 7 is a schematic diagram of a flow chart for determining a target battery pack branch in another embodiment;

[0070] Figure 8 is a schematic diagram of a flow chart for determining a target battery pack branch in another embodiment;

[0071] Figure 9is a flow chart of a method for determining a battery energy state in another embodiment;

[0072] Figure 10 1 is a schematic diagram of a process for connecting a branch to be connected to an energy transmission system in one embodiment;

[0073] Figure 11 A schematic diagram of a flow chart for determining a conduction sequence in one embodiment;

[0074] Figure 12 is a schematic diagram of a process for connecting a branch to be connected to an energy transmission system in another embodiment;

[0075] Figure 13 is a flow chart of a method for determining a battery energy state in another embodiment;

[0076] Figure 14 FIG. 1 is a structural block diagram of a device for determining a battery energy state in one embodiment. DETAILED DESCRIPTION

[0077] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0078] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the term "include" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0079] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0080] In the description of the embodiments of this application, the term "and / or" is merely a description of an association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. In the description of the embodiments of this application, the term "plurality" refers to two or more (including two), unless otherwise specifically defined.

[0081] With the development of new energy technologies, batteries are increasingly being used in various industries.

[0082] Taking new energy vehicles as an example, they typically use battery modules consisting of multiple parallel battery pack branches as their power source, and exchange energy with other devices through an energy transmission system. In related technologies, the Battery Management System (BMS) estimates the battery module's State of Energy (SOE) based on the battery pack branches within the battery module that are connected to the energy transmission system, thereby enabling monitoring and management of the battery module.

[0083] However, in actual applications, the BMS connects each battery pack branch to the energy transmission system based on the energy state of each battery pack branch in the battery module. Related technologies estimate SOE based on the battery pack branches connected to the energy transmission system, ignoring the energy contribution of the battery pack branches connected to the energy transmission system under future operating conditions. This makes it impossible to accurately measure the actual available energy of the battery module, resulting in poor accuracy in battery module energy state estimation.

[0084] Based on this, the present application provides a method for determining the battery energy status, which determines the energy status of the battery module by screening out target battery pack branches that can be continuously connected to the energy transmission system from the battery module. The screened out target battery pack branches are battery pack branches that can actually participate in energy transmission in the future, and can be used to accurately measure the actual available energy of the battery module, thereby achieving the technical effect of improving the accuracy of the energy status of the obtained battery module.

[0085] In one embodiment, a method for determining battery energy status is provided, which can be applied to Figure 1 In the application environment shown. Among them, the battery module 100 includes multiple parallel battery pack branches 101. The battery module 100 interacts with external devices through the energy transmission system 200, such as charging the battery module 100 through the external device, or discharging the external device through the battery module 100. Each battery pack branch 101 in the battery module 100 is connected to the energy transmission system 200 and the BMS 300 respectively. The BMS 300 can control the connection status between the battery pack branch 101 and the energy transmission system 200, such as closing the relay between the battery pack branch 101 and the energy transmission system 200 to connect the battery pack branch 101 and the energy transmission system 200, or disconnecting the relay between the battery pack branch 101 and the energy transmission system 200 to disconnect the battery pack branch 101 from the energy transmission system 200.

[0086] The battery pack in the battery pack branch 101 may include a plurality of single batteries or battery cells.

[0087] Those skilled in the art will understand that Figure 1 The structure shown in the figure is only a block diagram of a part of the structure related to the embodiment of the present application, and does not constitute a limitation on the computer device to which the embodiment of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0088] In one embodiment, the present application provides a method for determining battery energy status, such as Figure 2 As shown, this embodiment includes the following steps:

[0089] S210. Determine at least one target battery pack branch from the multiple battery pack branches based on the branch states of the multiple battery pack branches in the battery module; the at least one target battery pack branch includes at least one battery pack branch that is not connected to the energy transmission system of the battery module.

[0090] The branch status characterizes the operating status of a battery pack branch and can be either faulty or normal. For example, the branch status can be determined based on the current, voltage, or temperature of the battery pack branch. For example, the branch status can be determined based on the branch current / voltage to determine whether the battery pack branch is short-circuited. If so, the branch status of the battery pack branch is determined to be faulty. Alternatively, the battery pack temperature can be used to determine whether the battery pack is experiencing thermal runaway (e.g., if the temperature exceeds a threshold). If so, the branch status of the battery pack branch is determined to be faulty.

[0091] The energy transmission system is the channel through which the battery module exchanges energy with external devices. The battery module can be charged and discharged through the energy transmission system. If the battery pack branch is connected to the energy transmission system, it indicates that the switch (such as a relay) between the battery pack branch and the energy transmission system is closed. If the battery pack branch is not connected to the energy transmission system, it indicates that the switch (such as a relay) between the battery pack branch and the energy transmission system is open.

[0092] Optionally, the BMS may monitor the status of each battery pack branch in the battery module to determine whether each battery pack branch is faulty, and select battery pack branches with normal branch status as target battery pack branches.

[0093] S220: Determine the energy state of the battery module according to the remaining power of at least one target battery pack branch.

[0094] The battery module's State of Energy (SOE) measures the actual available energy in the battery module. For example, for battery modules used in new energy vehicles, the SOE can be used to estimate the vehicle's range.

[0095] Optionally, after screening the target battery pack branches from the battery module, the BMS may determine the state of charge (SOC) of the battery module according to the remaining power of each target battery pack branch, and then determine the SOE of the battery module based on the SOC of the battery module.

[0096] Exemplarily, for each target battery pack branch, the BMS can obtain the electrical status parameters of the target battery pack branch, such as current, voltage, and resistance, to determine the remaining power of the target battery pack branch based on the electrical status parameters of the target battery pack branch, and determine the SOC of the battery module based on the sum of the remaining power of all target battery pack branches, and then obtain the SOE of the battery module corresponding to the SOC of the battery module based on the correlation between SOC and SOE.

[0097] It should be noted that the remaining charge based on the target battery pack branch can be used not only to predict the energy state of the battery module, but also to predict other energy parameters of the battery module, such as the total remaining charge and output power. This can accordingly improve the accuracy of the battery module energy parameter prediction and reduce the occurrence of parameter jumps.

[0098] In an embodiment of the present application, at least one target battery pack branch is determined from the multiple battery pack branches based on the branch states of multiple battery pack branches in the battery module, so as to determine the energy state of the battery module based on the charge state of the at least one target battery pack branch; the at least one target battery pack branch includes at least one battery pack branch that is not connected to the energy transmission system of the battery module; in the above method, the target battery pack branch screened out from the battery module is used to determine the energy state of the battery module, and the screened out target battery pack branch includes the battery pack branch that can be subsequently connected to the energy transmission system, which can adapt to the actual situation that the battery pack branches in the battery module are connected to the energy transmission system one by one, so that the screened out target battery pack branch is the battery pack branch that can actually participate in energy transmission subsequently, which can be used to accurately measure the actual available energy of the battery module, thereby improving the accuracy of the obtained energy state of the battery module.

[0099] The branch status of the battery pack branch and the connection status of the battery pack branch and the energy transmission system will affect the selected target battery pack branch. Based on this, in one embodiment, if Figure 3 As shown, the above S210 determines at least one target battery pack branch from the multiple battery pack branches according to the branch states of the multiple battery pack branches in the battery module, including:

[0100] S310 , determining a plurality of candidate battery pack branches from the plurality of battery pack branches according to branch states of the plurality of battery pack branches in the battery module.

[0101] The candidate battery pack branches are battery pack branches that are screened out from the battery module and are in normal state.

[0102] Optionally, the BMS may monitor the status of each battery pack branch in the battery module to determine whether each battery pack branch is in a faulty branch state, and select battery pack branches with normal branch states as candidate battery pack branches.

[0103] S320 : Determine at least one target battery pack branch from a plurality of candidate battery pack branches according to the connection status of each candidate battery pack branch and the energy transmission system.

[0104] The connection status between the battery pack branch and the energy transmission system is used to indicate whether there is conduction between the battery pack branch and the energy transmission system.

[0105] Optionally, after screening the candidate battery pack branches, the BMS may obtain the connection status of each candidate battery pack branch and the energy transmission system to screen at least one target battery pack branch from the multiple candidate battery pack branches.

[0106] For example, when all candidate battery packs are connected to the energy transmission system, the BMS will take all candidate battery pack branches as target battery pack branches; when some candidate battery pack branches are connected to the energy transmission system and some candidate battery pack branches are not connected to the energy transmission system, the BMS may take the candidate battery pack branches connected to the energy transmission system as target battery pack branches, and further screen the target battery pack branches from the candidate battery pack branches not connected to the energy transmission system.

[0107] In an embodiment of the present application, multiple candidate battery pack branches are determined from the multiple battery pack branches based on the branch status of multiple battery pack branches in the battery module, and at least one target battery pack branch is determined from the multiple candidate battery pack branches based on the connection status of each candidate battery pack branch and the energy transmission system; in the above method, candidate battery pack branches are screened from the battery module based on the branch status, and then target battery pack branches are screened from the candidate battery pack branches based on the connection status, taking into account the influence of the branch status and the connection status on the screening of the target battery pack branches, thereby improving the accuracy of the obtained target battery pack branch.

[0108] In the case where some candidate battery pack branches are connected to the energy transmission system and some candidate battery pack branches are not connected to the energy transmission system, in one embodiment, if Figure 4 As shown, the above S320, determining at least one target battery pack branch from multiple candidate battery pack branches according to the connection status of each candidate battery pack branch and the energy transmission system, includes:

[0109] S410: Determine, from a plurality of candidate battery pack branches, at least one first branch that is connected to an energy transmission system and at least one second branch that is not connected to the energy transmission system.

[0110] Optionally, the BMS may determine, based on the connection status of each candidate battery pack branch and the energy transmission system, a candidate battery pack branch that is connected to the energy transmission system from all candidate battery pack branches as the first branch, and determine a candidate battery pack branch that is not connected to the energy transmission system from all candidate battery pack branches as the second branch.

[0111] S420: Determine at least one target battery pack branch from a plurality of candidate battery pack branches based on the voltages of at least one first branch and at least one second branch, and an energy transmission mode of the battery module.

[0112] The energy transmission mode of the battery module is used to characterize the working mode of the battery module, which can be a charging mode or a discharging mode.

[0113] Optionally, the BMS may take the first branch of all candidate battery pack branches as the target battery pack branch, and further screen the target battery pack branch in the second branch according to the voltage of each first branch, the voltage of each second branch and the energy transmission mode of the battery module.

[0114] For example, the BMS can compare the voltage of each first branch with the voltage of each second branch, identify the second branch from all second branches whose voltage relationship with the first branch satisfies the voltage relationship under the corresponding energy transfer mode, and use all first branches and the second branches that meet the voltage relationship as the target battery pack branch. The voltage relationship required to be met varies in different energy transfer modes.

[0115] In an embodiment of the present application, at least one first branch that is connected to the energy transmission system and at least one second branch that is not connected to the energy transmission system are determined from multiple candidate battery pack branches, so as to determine at least one target battery pack branch from the multiple candidate battery pack branches based on the voltages of the at least one first branch and the at least one second branch, and the energy transmission mode of the battery module; in the above method, the energy transmission mode of the battery module and the voltages of the candidate battery pack branches in different connection states will affect whether the candidate battery pack branches that are not connected to the energy transmission system can be normally connected under future working conditions. Therefore, by utilizing the energy transmission mode of the battery module and the voltages of the candidate battery pack branches in different connection states to determine the target battery pack branch from the candidate battery pack branches, the reliability of the determined target battery pack branch can be improved.

[0116] To obtain the target battery pack branch, in one embodiment, as Figure 5As shown, the above S320, determining at least one target battery pack branch from multiple candidate battery pack branches according to the connection status of each candidate battery pack branch and the energy transmission system, includes:

[0117] S510: Determine, from a plurality of candidate battery pack branches, at least one first branch that is connected to an energy transmission system and at least one second branch that is not connected to the energy transmission system.

[0118] Optionally, the BMS may determine, based on the connection status of each candidate battery pack branch and the energy transmission system, a candidate battery pack branch that is connected to the energy transmission system from all candidate battery pack branches as the first branch, and determine a candidate battery pack branch that is not connected to the energy transmission system from all candidate battery pack branches as the second branch.

[0119] S520: Determine a branch with a maximum voltage in at least one first branch according to the energy transmission mode of the battery module and the voltages of the first branches.

[0120] The maximum voltage branch is the first branch with the largest or smallest voltage among all first branches.

[0121] Optionally, the BMS can obtain the energy transmission mode of the battery module and the voltage of each first branch, and compare the voltage of each first branch to determine the first branch with the largest voltage and the first branch with the smallest voltage, and then select one of the first branch with the largest voltage and the first branch with the smallest voltage as the branch with the maximum voltage according to the energy transmission mode of the battery module.

[0122] S530 : Determine at least one target battery pack branch from a plurality of candidate battery pack branches based on the voltage of the maximum voltage branch and the voltage of at least one second branch.

[0123] Optionally, after obtaining the branch with the maximum voltage in the first branch, the BMS can compare the voltage of the branch with the voltage of each second branch, determine from all second branches the second branch whose voltage relationship with the branch with the maximum voltage satisfies the voltage relationship under the corresponding energy transfer mode, and use all first branches and second branches that meet the voltage relationship as target battery pack branches. The voltage relationship required to be met varies in different energy transfer modes.

[0124] In an embodiment of the present application, a maximum voltage branch is determined in at least one first branch based on the energy transmission mode of the battery module and the voltage of each first branch, and at least one target battery pack branch is determined from multiple candidate battery pack branches based on the voltage of the maximum voltage branch and the voltage of at least one second branch; in the above method, the maximum voltage branch is determined in the first branch based on the energy transmission mode, so as to determine the target battery pack branch from the candidate battery pack branches based on the voltage of the maximum voltage branch and each second branch, which helps to subsequently eliminate the candidate battery pack branches that cannot be connected to the energy transmission system through voltage comparison, thereby realizing rapid screening of the target battery pack branches and improving the overall efficiency of battery energy status determination.

[0125] The determination method of the voltage maximum branch is different in different energy transmission modes. In one embodiment, Figure 6 As shown, the above S520, determining a branch with a maximum voltage in at least one first branch according to the energy transmission mode of the battery module and the voltage of each first branch, includes:

[0126] S610: When the energy transmission mode of the battery module is the discharge mode, determine a first branch with the minimum voltage in at least one first branch according to the voltages of the first branches as the maximum voltage branch.

[0127] Optionally, the BMS compares the voltages of the first branches and, when the energy transmission mode of the battery module is the discharge mode, determines the first branch with the smallest voltage among all the first branches as the branch with the maximum voltage among all the first branches of the battery module in the discharge mode.

[0128] S620: When the energy transmission mode of the battery module is the charging mode, determine a first branch with the largest voltage in at least one first branch according to the voltages of the first branches as the maximum voltage branch.

[0129] Optionally, the BMS compares the voltages of the first branches and, when the energy transmission mode of the battery module is the charging mode, determines the first branch with the largest voltage among all the first branches as the branch with the maximum voltage among all the first branches of the battery module in the discharging mode.

[0130] In an embodiment of the present application, when the energy transmission mode of the battery module is a discharge mode, the first branch with the smallest voltage is determined in at least one first branch according to the voltage of each first branch, as the voltage maximum branch; when the energy transmission mode of the battery module is a charging mode, the first branch with the largest voltage is determined in at least one first branch according to the voltage of each first branch, as the voltage maximum branch; in the above method, in the discharge mode of the battery module, the first branch with the smallest voltage is adopted as the voltage maximum branch, and in the charging mode of the battery module, the first branch with the largest voltage is adopted as the voltage maximum branch, so as to clarify the voltage maximum branch adopted for screening the target battery pack branch under different working states of the battery module, improve the adaptability of the voltage maximum branch and the working state of the battery module, and thus improve the accuracy and reliability of the target battery pack branch obtained under different working states of the battery module.

[0131] In practical applications, the target battery pack branch can be determined by the relationship between the voltage of the maximum voltage branch and the voltage of each second branch. Figure 7 As shown, the above S520, determining at least one target battery pack branch from a plurality of candidate battery pack branches based on the voltage of the maximum voltage branch and the voltage of at least one second branch, includes:

[0132] S710 : Compare the voltage of each second branch with the voltage of the maximum voltage branch to obtain a voltage magnitude relationship between each second branch and the maximum voltage branch.

[0133] Optionally, the BMS may compare the voltage of each second branch with the voltage of the maximum voltage branch, and obtain the voltage magnitude relationship between each second branch and the maximum voltage branch.

[0134] S720: Determine at least one target battery pack branch from a plurality of candidate battery pack branches based on the energy transmission mode of the battery module and the relationship between the voltages.

[0135] Optionally, after obtaining the above-mentioned voltage magnitude relationship, the BMS can determine a reference magnitude relationship based on the energy transmission mode of the battery module, and match the actual voltage magnitude relationships obtained with the reference magnitude relationship to determine at least one target battery pack branch from multiple candidate battery pack branches based on the matching results.

[0136] For example, when the matching result is that all actually obtained voltage size relationships satisfy the reference size relationship, the BMS takes all candidate battery pack branches as target battery pack branches; when the matching result is that there is a voltage size relationship that does not satisfy the reference size relationship among all actually obtained voltage size relationships, the BMS may take the first branch of all candidate battery pack branches and the second branch that satisfies the reference size relationship as the target battery pack branch.

[0137] In an embodiment of the present application, by comparing the voltage of each second branch with the voltage of the maximum voltage branch, the voltage magnitude relationship between each second branch and the maximum voltage branch is obtained, so as to determine at least one target battery pack branch from multiple candidate battery pack branches according to the energy transmission mode of the battery module and each voltage magnitude relationship; in the above method, the above voltage magnitude relationship under different energy transmission modes can be used to estimate whether the second branch can be connected to the energy transmission system, and the target battery pack branch is determined based on the above voltage magnitude relationship and the energy transmission mode of the battery module, which can improve the reliability of the target battery pack branch obtained to successfully connect to the energy transmission system and participate in energy interaction, and use the target battery pack branch that can participate in energy interaction to predict the energy state of the battery module, thereby correspondingly improving the accuracy of the energy state prediction.

[0138] For the case where the energy transmission mode of the battery module is the discharge mode, in one embodiment, as Figure 8 As shown, the above S720, based on the energy transmission mode of the battery module and the relationship between the voltages, determines at least one target battery pack branch from multiple candidate battery pack branches, including:

[0139] S810: When the energy transmission mode of the battery module is the discharge mode and there is no second branch whose voltage is greater than the voltage of the maximum voltage branch in all voltage magnitude relationships, each candidate battery pack branch is used as the target battery pack branch.

[0140] It should be noted that in discharge mode, the BMS connects the battery pack branches in the battery module to the energy transmission system in descending order of voltage. Under normal circumstances, the voltage of all unconnected second branches in the battery module should be less than or equal to the voltage of the branch with the lowest voltage among all connected first branches.

[0141] In the discharge mode, the maximum voltage branch is the minimum voltage branch in the first branch of the battery module.

[0142] In actual working conditions, there is no situation where the voltage of the second branch is greater than the voltage of the branch with the maximum voltage. This indicates that the voltage of the second branch of the battery module has not changed due to external influences. The BMS can continue to connect each second branch to the energy transmission system in sequence from high to low voltage.

[0143] Optionally, when the energy transmission mode of the battery module is the discharge mode, and there is no second branch whose voltage is greater than the voltage of the maximum voltage branch in all voltage magnitude relationships, it is characterized that each second branch in the battery module that is not connected to the energy transmission system can subsequently be connected to the energy transmission system normally, and the BMS will take each candidate battery pack branch as the target battery pack branch.

[0144] S820. When the energy transmission mode of the battery module is the discharge mode and there is a second branch whose voltage is greater than the voltage of the maximum voltage branch in all voltage magnitude relationships, eliminate the second branch whose voltage is greater than the voltage of the maximum voltage branch from multiple candidate battery pack branches to obtain at least one target battery pack branch.

[0145] In actual operating conditions, the voltage of the second branch may be greater than the voltage of the branch with the maximum voltage. This indicates that the voltage of the second branch has increased due to external influences on the battery module, and is higher than the voltage of the branch with the lowest voltage among all the first branches that are conductive. If the battery module's energy transmission mode is not switched, this second branch will subsequently be unable to conduct electricity with the energy transmission system.

[0146] Optionally, when the energy transmission mode of the battery module is the discharge mode, and in all voltage magnitude relationships there is a second branch whose voltage is greater than the voltage of the maximum voltage branch, the second branch in the battery module whose voltage is greater than the voltage of the maximum voltage branch cannot be subsequently connected to the energy transmission system, and the BMS eliminates the second branch in the candidate battery pack branch whose voltage is greater than the voltage of the maximum voltage branch, and uses the remaining candidate battery pack branches as the target battery pack branches.

[0147] In an embodiment of the present application, when the energy transmission mode of the battery module is a discharge mode, and there is no second branch whose voltage is greater than the voltage of the maximum voltage branch in all voltage magnitude relationships, each candidate battery pack branch is used as a target battery pack branch; when the energy transmission mode of the battery module is a discharge mode, and there is a second branch whose voltage is greater than the voltage of the maximum voltage branch in all voltage magnitude relationships, the second branch whose voltage is greater than the voltage of the maximum voltage branch is eliminated from multiple candidate battery pack branches to obtain at least one target battery pack branch; in the above method, the specific method of determining the target battery pack branch in the discharge mode is clarified, and it is adapted to the conduction strategy of the battery pack branch and the energy transmission system in the discharge mode, thereby improving the reliability of the target battery pack branch in the discharge mode, and correspondingly improving the accuracy of the battery module energy state determined based on the reliable target battery pack branch.

[0148] For the case where the energy transmission mode of the battery module is the charging mode, in one embodiment, as Figure 8 As shown, the above S720, determining at least one target battery pack branch from multiple candidate battery pack branches based on the energy transmission mode of the battery module and the relationship between the voltages, further includes:

[0149] S830: When the energy transmission mode of the battery module is the charging mode and there is no second branch whose voltage is less than the voltage of the maximum voltage branch in all voltage magnitude relationships, each candidate battery pack branch is used as the target battery pack branch.

[0150] It should be noted that in charging mode, the BMS connects the battery pack branches in the battery module to the energy transmission system in ascending order of voltage. Under normal circumstances, the voltage of all unconnected second branches in the battery module should be greater than or equal to the voltage of the branch with the highest voltage among all connected first branches.

[0151] In charging mode, the maximum voltage branch is the branch with the maximum voltage in the first branch of the battery module.

[0152] In actual working conditions, there is no situation where the voltage of the second branch is lower than the voltage of the branch with the maximum voltage. This indicates that the voltage of the second branch of the battery module has not changed due to external influences. The BMS can continue to connect each second branch to the energy transmission system in order from low to high voltage.

[0153] Optionally, when the energy transmission mode of the battery module is the charging mode, and there is no second branch whose voltage is less than the voltage of the maximum voltage branch in all voltage magnitude relationships, it is characterized that each second branch in the battery module that is not connected to the energy transmission system can subsequently be connected to the energy transmission system normally, and the BMS will take each candidate battery pack branch as the target battery pack branch.

[0154] S840. When the energy transmission mode of the battery module is the charging mode and there is a second branch whose voltage is lower than the voltage of the maximum voltage branch in all voltage magnitude relationships, eliminate the second branch whose voltage is lower than the voltage of the maximum voltage branch from multiple candidate battery pack branches to obtain at least one target battery pack branch.

[0155] In actual operating conditions, the voltage of the second branch may be lower than the voltage of the branch with the maximum voltage. This indicates that the voltage of the second branch has dropped due to external influences on the battery module, and is lower than the voltage of the branch with the highest voltage among all the first branches that are turned on. If the battery module's energy transmission mode is not switched, this second branch will subsequently be unable to conduct electricity with the energy transmission system.

[0156] Optionally, when the energy transmission mode of the battery module is the charging mode, and in all voltage magnitude relationships there is a second branch whose voltage is lower than the voltage of the maximum voltage branch, the second branch in the battery module whose voltage is lower than the voltage of the maximum voltage branch cannot be subsequently connected to the energy transmission system, and the BMS eliminates the second branch in the candidate battery pack branch whose voltage is lower than the voltage of the maximum voltage branch, and uses the remaining candidate battery pack branches as the target battery pack branches.

[0157] In an embodiment of the present application, when the energy transmission mode of the battery module is a charging mode, and there is no second branch whose voltage is less than the voltage of the maximum voltage branch in all voltage magnitude relationships, each candidate battery pack branch is taken as a target battery pack branch; when the energy transmission mode of the battery module is a charging mode, and there is a second branch whose voltage is less than the voltage of the maximum voltage branch in all voltage magnitude relationships, the second branch whose voltage is less than the voltage of the maximum voltage branch is eliminated from multiple candidate battery pack branches to obtain at least one target battery pack branch; in the above method, the specific method of determining the target battery pack branch in the charging mode is clarified, and it is adapted to the conduction strategy of the battery pack branch and the energy transmission system in the charging mode, thereby improving the reliability of the target battery pack branch in the charging mode, and correspondingly improving the accuracy of the battery module energy state determined based on the reliable target battery pack branch.

[0158] When the energy transmission mode of the battery module is switched, in one embodiment, Figure 9 As shown, the above method also includes:

[0159] S910: When all target battery pack branches are connected to the energy transmission system and the energy transmission mode of the battery module is switched, obtain at least one branch to be connected in the battery module that is not connected to the energy transmission system.

[0160] The energy transmission mode of the battery module may be switched from a charging mode to a discharging mode, or from a discharging mode to a charging mode.

[0161] Optionally, after all battery pack branches in the battery module that can be connected to the energy transmission system, that is, all target battery pack branches, are connected to the energy transmission system, the BMS can monitor whether the energy transmission mode of the battery module is switched, and if switching occurs, obtain the battery pack branches in the battery module that are not connected to the energy transmission system as the branches to be connected.

[0162] S920: Connect each branch to be connected to the energy transmission system according to the target transmission mode switched to by the battery module and the voltage of at least one branch to be connected.

[0163] Optionally, the BMS can determine the priority of each battery pack branch based on the target transmission mode switched to by the battery module and the voltage of each branch to be turned on, so as to turn on each branch to be turned on in batches with the energy transmission system according to the priority.

[0164] In an embodiment of the present application, when each target battery pack branch is connected to the energy transmission system and the energy transmission mode of the battery module is switched, at least one branch to be connected in the battery module that is not connected to the energy transmission system is obtained, and each branch to be connected is connected to the energy transmission system according to the target transmission mode to which the battery module is switched and the voltage of at least one branch to be connected; in the above method, when the energy transmission mode of the battery module is switched, each target battery pack that has been connected to the energy transmission system does not need to be disconnected and then connected, and the remaining branches to be connected can continue to be connected to the energy transmission system according to the target transmission mode, thereby improving the mode switching efficiency, reducing the switching loss of the mode switching, and extending the service life of the switch.

[0165] The target transmission mode determines the order in which each branch to be turned on is turned on with the energy transmission system. Therefore, in one embodiment, if Figure 10 As shown, the above method also includes:

[0166] S1010: When all target battery pack branches are connected to the energy transmission system and the energy transmission mode of the battery module is switched, obtain at least one branch to be connected in the battery module that is not connected to the energy transmission system.

[0167] The energy transmission mode of the battery module may be switched from a charging mode to a discharging mode, or from a discharging mode to a charging mode.

[0168] Optionally, after all battery pack branches in the battery module that can be connected to the energy transmission system, that is, all target battery pack branches, are connected to the energy transmission system, the BMS can monitor whether the energy transmission mode of the battery module is switched, and if switching occurs, obtain the battery pack branches in the battery module that are not connected to the energy transmission system as the branches to be connected.

[0169] S1020: Determine a conduction order in which the branches to be conducted are conducted with the energy transmission system according to the target transmission mode and the voltage of at least one branch to be conducted.

[0170] Among them, different target transmission modes correspond to different conduction sequences.

[0171] Optionally, the BMS may sort the voltages of the branches to be turned on according to their voltages, and select the voltage sorting corresponding to the target transmission mode as the turn-on order for the branches to be turned on to conduct with the energy transmission system.

[0172] S1030 , connecting each branch to be connected to the energy transmission system in sequence according to the connection sequence.

[0173] Optionally, after obtaining the conduction sequence, the BMS may sequentially conduct each branch to be conducted with the energy transmission system according to the conduction sequence. For example, the BMS may sequentially conduct each branch to be conducted with the energy transmission system in the order of high to low voltage, or may sequentially conduct each branch to be conducted with the energy transmission system in the order of low to high voltage.

[0174] In an embodiment of the present application, the conduction order of each branch to be conducted and the energy transmission system is determined according to the target transmission mode and the voltage of at least one branch to be conducted, so that each branch to be conducted is conducted with the energy transmission system in turn according to the conduction order; in the above method, the conduction order is determined based on the target transmission mode and the voltage of each branch to be conducted, so that each branch to be conducted is conducted with the energy transmission system in turn according to the conduction order, thereby achieving orderly conduction of each branch to be conducted and improving the stability of the battery module.

[0175] The target transmission mode switched to by the battery module is different, and the corresponding conduction sequence is also different. In one embodiment, Figure 11 As shown, the above S1020, determining the conduction order of each branch to be conducted and the energy transmission system according to the target transmission mode and the voltage of at least one branch to be conducted, includes:

[0176] S1110 : When the target transmission mode is the discharge mode, the order of the voltages of the branches to be turned on, from large to small, is used as the turn-on order.

[0177] In discharge mode, the battery pack branch with the most remaining charge is preferentially connected to the energy transmission system for discharge. The more remaining charge in the battery pack branch, the higher the voltage.

[0178] Optionally, when the target transmission mode is the discharge mode, the BMS may use the order of the voltages of the branches to be turned on from large to small as the turn-on order of the branches to be turned on and the energy transmission system.

[0179] S1120: When the target transmission mode is the charging mode, the order of the voltages of the branches to be turned on from small to large is used as the turn-on order.

[0180] In charging mode, the battery pack branch with the least remaining power is preferentially connected to the energy transmission system for charging. The less remaining power in the battery pack branch, the lower the voltage.

[0181] Optionally, when the target transmission mode is the charging mode, the BMS may use the order of the voltages of the branches to be turned on from small to large as the turn-on order of the branches to be turned on and the energy transmission system.

[0182] In an embodiment of the present application, when the target transmission mode is the discharge mode, the voltages of the branches to be turned on are arranged in descending order as the conduction order; when the target transmission mode is the charging mode, the voltages of the branches to be turned on are arranged in descending order as the conduction order; in the above method, the conduction order of the battery module under different energy transmission modes is clarified, and it is adapted to different mode switches, thereby improving the stability of the battery module working mode switching and the stability of the operation after switching.

[0183] In order to connect the branch to be connected with the energy transmission system, in one embodiment, the above S1030, connecting each branch to be connected with the energy transmission system in sequence according to the connection order, includes:

[0184] Prioritize the conduction of the pre-charge branch between the first branch to be conducted and the energy transmission system according to the conduction sequence;

[0185] When the voltage of the first branch to be turned on meets the voltage requirement of the target transmission mode, the first branch to be turned on is turned on to the energy transmission system, and the remaining branches to be turned on are turned on to the energy transmission system in sequence according to the turn-on order.

[0186] Among them, there are two transmission branches between each battery pack branch in the battery module and the energy transmission system, including the pre-charge branch. For example, Figure 1 As shown, the branch including the load R between the battery pack branch 101 and the energy transmission system 200 is the pre-charging branch of the connected battery pack branch 101 .

[0187] Optionally, after the conduction sequence is determined, the BMS may prioritize conducting the pre-charge branch between the first branch to be conducted and the energy transmission system according to the conduction sequence. For example, the BMS may control the closing of a relay on the pre-charge branch between the first branch to be conducted and the energy transmission system to conduct the pre-charge branch.

[0188] Among them, after the pre-stored branch of the branch to be turned on is turned on, the branch to be turned on will participate in energy interaction, and the voltage will change accordingly.

[0189] Optionally, after the pre-charge branch of the first branch to be turned on is turned on, the BMS can continue to monitor the voltage of the first branch to be turned on, and when the voltage meets the voltage requirement of the corresponding target transmission mode, close another transmission branch between the first branch to be turned on and the energy transmission system, thereby turning on the first branch to be turned on and the energy transmission system. Referring to the above turn-on process, the remaining branches to be turned on are turned on to the energy transmission system in turn according to the turn-on sequence.

[0190] In an embodiment of the present application, the pre-charge branch between the first branch to be conducted and the energy transmission system is preferentially conducted in the conduction order, so that when the voltage of the first branch to be conducted meets the voltage requirement of the target transmission mode, the first branch to be conducted is conducted with the energy transmission system, and the remaining branches to be conducted are conducted with the energy transmission system in turn according to the conduction order; in the above method, the voltage of the branch to be conducted is changed by conducting the pre-charge branch between the branch to be conducted and the energy transmission system, so that the branch to be conducted can meet the voltage requirement under the corresponding target transmission mode, thereby improving the success rate of conduction between the branch to be conducted and the energy transmission system.

[0191] In one embodiment, the target transmission mode is a discharge mode, and the voltage requirements of the target transmission mode include: the voltage of the branch to be turned on is less than the voltage of the battery pack branch in the battery module that was last turned on with the energy transmission system, and the voltage difference is less than the first voltage difference.

[0192] Among them, in the discharge mode, the BMS connects each battery pack branch to the energy transmission in sequence according to the voltage from large to small, and the battery pack branch connected to the energy transmission system participates in the discharge, and the voltage gradually decreases.

[0193] Optionally, in the discharge mode, the voltage of the battery pack branch that was last connected to the energy transmission system gradually decreases. When the voltage difference between the branch to be connected and the branch to be connected decreases to a value less than a preset first voltage difference, the BMS can connect the branch to be connected to the energy transmission system.

[0194] In one embodiment, the target transmission mode is a charging mode, and the voltage requirements of the target transmission mode include: the voltage of the branch to be turned on is greater than the voltage of the battery pack branch in the battery module that was last turned on with the energy transmission system, and the voltage difference is greater than the second voltage difference.

[0195] Among them, in the charging mode, the BMS connects each battery pack branch to the energy transmission system in sequence according to the voltage from small to large. The battery pack branches connected to the energy transmission system participate in charging, and the voltage gradually increases.

[0196] Optionally, in charging mode, the voltage of the battery pack branch that was last connected to the energy transmission system gradually increases. When the voltage difference between the branch to be connected and the branch to be connected increases to a value greater than a preset second voltage difference, the BMS can connect the branch to be connected to the energy transmission system.

[0197] It should be noted that the first pressure difference and the second pressure difference may be the same or different.

[0198] In one embodiment, Figure 12 As shown, the above S1030, sequentially connecting each branch to be connected to the energy transmission system according to the connection sequence, includes:

[0199] S1210, preferentially conducting the pre-charge branch between the first branch to be conducted and the energy transmission system according to the conduction order;

[0200] S1220: In the discharge mode, when the voltage of the first branch to be connected is lower than the voltage of the battery pack branch in the battery module that was previously connected to the energy transmission system, and the voltage difference is lower than the first voltage difference, the first branch to be connected is connected to the energy transmission system, and the remaining branches to be connected are connected to the energy transmission system in sequence according to the connection order.

[0201] S1230. In the charging mode, when the voltage of the first branch to be turned on is greater than the voltage of the battery pack branch in the battery module that was previously turned on to the energy transmission system, and the voltage difference is greater than the second voltage difference, the first branch to be turned on is turned on to the energy transmission system, and the remaining branches to be turned on are turned on to the energy transmission system in sequence according to the turn-on order.

[0202] To facilitate understanding by those skilled in the art, the battery energy status determination method provided in this application is described in detail below. Figure 13 As shown, the method may include:

[0203] S1301, determining multiple candidate battery pack branches from the multiple battery pack branches based on whether the multiple battery pack branches in the battery module are in normal branch status;

[0204] S1302: Determine, based on whether multiple candidate battery pack branches are connected to the energy transmission system, at least one first branch connected to the energy transmission system and at least one second branch not connected to the energy transmission system;

[0205] S1303: When the energy transmission mode of the battery module is the discharge mode, determine, based on the voltages of the first branches, a first branch with the smallest voltage among at least one first branch as the maximum voltage branch;

[0206] S1304: When the energy transmission mode of the battery module is the charging mode, determine, based on the voltages of the first branches, a first branch with the largest voltage among at least one first branch as the maximum voltage branch;

[0207] S1305: Compare the voltage of each second branch with the voltage of the maximum voltage branch to obtain a voltage magnitude relationship between each second branch and the maximum voltage branch;

[0208] S1306: When the energy transmission mode of the battery module is the discharge mode and there is no second branch whose voltage is greater than the voltage of the maximum voltage branch in all voltage magnitude relationships, select each candidate battery pack branch as the target battery pack branch;

[0209] S1307: If the energy transmission mode of the battery module is a discharge mode and the voltage of a second branch is greater than the voltage of the maximum voltage branch in all voltage magnitude relationships, eliminate the second branches having a voltage greater than the voltage of the maximum voltage branch from the multiple candidate battery pack branches to obtain at least one target battery pack branch.

[0210] S1308: When the energy transmission mode of the battery module is the charging mode and there is no second branch whose voltage is less than the voltage of the maximum voltage branch in all voltage magnitude relationships, select all candidate battery pack branches as target battery pack branches;

[0211] S1309: If the energy transmission mode of the battery module is the charging mode and the voltage of the second branch in all voltage magnitude relationships is lower than the voltage of the maximum voltage branch, eliminate the second branches whose voltage is lower than the voltage of the maximum voltage branch from the multiple candidate battery pack branches to obtain at least one target battery pack branch.

[0212] S1310, determining the energy state of the battery module according to the remaining power of at least one target battery pack branch;

[0213] S1311, determining whether each target battery pack branch is connected to the energy transmission system and whether the energy transmission mode of the battery module is switched;

[0214] S1312: When all target battery pack branches are connected to the energy transmission system and the energy transmission mode of the battery module is switched, obtaining at least one branch to be connected in the battery module that is not connected to the energy transmission system;

[0215] S1313. When the target transmission mode is the discharge mode, the voltages of the branches to be turned on are arranged in descending order as the turn-on order; when the target transmission mode is the charge mode, the voltages of the branches to be turned on are arranged in descending order as the turn-on order;

[0216] S1314: preferentially conduct the pre-charge branch between the first branch to be conducted and the energy transmission system according to the conduction order;

[0217] S1315. In the discharge mode, if the voltage of the first branch to be connected is lower than the voltage of the battery pack branch in the battery module that was previously connected to the energy transmission system, and the voltage difference is lower than the first voltage difference, the first branch to be connected is connected to the energy transmission system, and the remaining branches to be connected are connected to the energy transmission system in sequence according to the connection order.

[0218] S1316. In the charging mode, when the voltage of the first branch to be turned on is greater than the voltage of the battery pack branch in the battery module that was previously turned on to the energy transmission system, and the voltage difference is greater than the second voltage difference, the first branch to be turned on is turned on to the energy transmission system, and the remaining branches to be turned on are turned on to the energy transmission system in sequence according to the turn-on order.

[0219] It should be noted that for the description in the above S1301-S1316, reference can be made to the relevant description in the above embodiment, and the effects are similar, so this embodiment will not be repeated here.

[0220] It should be understood that, although the various steps in the flowcharts involved in the various embodiments described above are displayed in sequence according to the instructions of the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the flowcharts involved in the various embodiments described above can include multiple steps or multiple stages, and these steps or stages are not necessarily executed and completed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0221] In one embodiment, Figure 14 As shown, a battery energy state determination device is provided, including: a branch determination module 1401 and a state estimation module 1402; wherein:

[0222] The branch determination module 1401 is configured to determine at least one target battery pack branch from the plurality of battery pack branches based on the branch states of the plurality of battery pack branches in the battery module; the at least one target battery pack branch includes at least one battery pack branch that is not connected to the energy transmission system of the battery module;

[0223] The state estimation module 1402 is used to determine the energy state of the battery module according to the remaining power of at least one target battery pack branch.

[0224] Each module in the battery energy status determination device described above may be implemented in whole or in part through software, hardware, or a combination thereof. Each module may be embedded in or independent of a processor in a computer device in the form of hardware, or may be stored in a memory in the computer device in the form of software, so that the processor can call and execute the corresponding operations of each module.

[0225] In one embodiment, a battery management system is provided, including a memory and a processor. The memory stores a computer program, and the processor implements the steps of any of the above-mentioned battery energy status determination methods when executing the computer program.

[0226] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of any of the above-mentioned battery energy status determination methods are implemented.

[0227] In one embodiment, a computer program product is provided, comprising a computer program, which implements the steps of any of the above-mentioned battery energy status determination methods when executed by a processor.

[0228] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the above-mentioned embodiments. In particular, any reference to memory, database, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The databases involved in the various embodiments provided herein may include at least one of a relational database and a non-relational database. Non-relational databases may include, but are not limited to, distributed databases based on blockchains. The processors involved in the various embodiments provided herein may be, but are not limited to, general-purpose processors, central processing units (CPUs), graphics processing units (GPUs), digital signal processors (DSPs), programmable logic devices (PLDs), data processing logic devices based on quantum computing, and the like.

[0229] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0230] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A method for determining battery energy status, characterized in that: The method comprises: According to branch states of multiple battery pack branches in the battery module, determining multiple candidate battery pack branches with normal branch states from the multiple battery pack branches; Determining at least one first branch that is connected to an energy transmission system and at least one second branch that is not connected to the energy transmission system from among the plurality of candidate battery pack branches; Determining at least one target battery pack branch from the plurality of candidate battery pack branches based on the voltages of the at least one first branch and the at least one second branch, and the energy transmission mode of the battery module; the at least one target battery pack branch includes at least one battery pack branch that is not electrically connected to the energy transmission system of the battery module; the at least one target battery pack branch includes the first branch, and a second branch of the second branch that satisfies a voltage relationship with the first branch under the energy transmission mode; The energy state of the battery module is determined according to the remaining power of the at least one target battery pack branch.

2. The method according to claim 1, characterized in that The determining, based on the voltages of the at least one first branch and the at least one second branch, and the energy transmission mode of the battery module, at least one target battery pack branch from the plurality of candidate battery pack branches includes: Determining a branch with a maximum voltage in the at least one first branch according to the energy transmission mode of the battery module and the voltage of each of the first branches; At least one target battery pack branch is determined from the plurality of candidate battery pack branches according to the voltage of the maximum voltage branch and the voltage of the at least one second branch.

3. The method according to claim 2, characterized in that The determining a branch with a maximum voltage in the at least one first branch according to the energy transmission mode of the battery module and the voltage of each of the first branches includes: When the energy transmission mode of the battery module is a discharge mode, determining a first branch with the smallest voltage among the at least one first branch according to the voltages of the first branches as the maximum voltage branch; When the energy transmission mode of the battery module is the charging mode, a first branch with the largest voltage is determined in the at least one first branch according to the voltages of the first branches as the maximum voltage branch.

4. The method according to claim 2 or 3, characterized in that The determining, based on the voltage of the maximum voltage branch and the voltage of the at least one second branch, at least one target battery pack branch from the plurality of candidate battery pack branches includes: Comparing the voltage of each second branch with the voltage of the maximum voltage branch to obtain a voltage magnitude relationship between each second branch and the maximum voltage branch; At least one target battery pack branch is determined from the plurality of candidate battery pack branches according to the energy transmission mode of the battery module and the relationship between the voltages.

5. The method according to claim 4, characterized in that The determining, based on the energy transmission mode of the battery module and the voltage magnitude relationship, at least one target battery pack branch from the plurality of candidate battery pack branches includes: When the energy transmission mode of the battery module is a discharge mode and the voltage of the second branch does not exist in all voltage magnitude relationships and is greater than the voltage of the maximum voltage branch, each of the candidate battery pack branches is used as the target battery pack branch; When the energy transmission mode of the battery module is the discharge mode, and in all voltage magnitude relationships, the voltage of the second branch is greater than the voltage of the maximum voltage branch, the second branch whose voltage is greater than the voltage of the maximum voltage branch is eliminated from the multiple candidate battery pack branches to obtain the at least one target battery pack branch.

6. The method according to claim 4, characterized in that The determining, based on the energy transmission mode of the battery module and the voltage magnitude relationship, at least one target battery pack branch from the plurality of candidate battery pack branches includes: When the energy transmission mode of the battery module is the charging mode and there is no voltage relationship in which the voltage of the second branch is less than the voltage of the maximum voltage branch, each of the candidate battery pack branches is used as the target battery pack branch; When the energy transmission mode of the battery module is the charging mode, and in all voltage magnitude relationships, the voltage of the second branch is smaller than the voltage of the maximum voltage branch, the second branch whose voltage is smaller than the voltage of the maximum voltage branch is eliminated from the multiple candidate battery pack branches to obtain the at least one target battery pack branch.

7. The method according to any one of claims 1 to 3, characterized in that The method further comprises: When all target battery pack branches are connected to the energy transmission system and the energy transmission mode of the battery module is switched, obtaining at least one to-be-connected branch in the battery module that is not connected to the energy transmission system; According to the target transmission mode to which the battery module is switched and the voltage of the at least one branch to be turned on, each branch to be turned on is turned on and the energy transmission system.

8. The method according to claim 7, characterized in that The step of connecting each branch to be connected to the energy transmission system according to the target transmission mode switched to by the battery module and the voltage of the at least one branch to be connected includes: determining, according to the target transmission mode and the voltage of the at least one branch to be turned on, a conduction order in which the branches to be turned on are connected to the energy transmission system; The branches to be turned on are sequentially turned on with the energy transmission system according to the turn-on sequence.

9. The method according to claim 8, characterized in that The determining, based on the target transmission mode and the voltage of the at least one branch to be turned on, a conduction order in which the branches to be turned on are connected to the energy transmission system includes: When the target transmission mode is the discharge mode, the order of the voltages of the branches to be turned on from large to small is used as the turn-on order; When the target transmission mode is the charging mode, the order of the voltages of the branches to be turned on from small to large is used as the turn-on order.

10. The method according to claim 8, characterized in that The step of sequentially connecting each of the branches to be connected to the energy transmission system according to the connection sequence includes: Prioritizing the conduction of the pre-charge branch between the first branch to be conducted and the energy transmission system according to the conduction sequence; When the voltage of the first branch to be turned on meets the voltage requirement of the target transmission mode, the first branch to be turned on is turned on with the energy transmission system, and the remaining branches to be turned on are turned on with the energy transmission system in sequence according to the turn-on order.

11. The method according to claim 10, characterized in that The target transmission mode is a discharge mode, and the voltage requirements of the target transmission mode include: the voltage of the branch to be turned on is less than the voltage of the battery pack branch in the battery module that was last turned on with the energy transmission system, and the voltage difference is less than the first voltage difference.

12. The method according to claim 10, characterized in that The target transmission mode is a charging mode, and the voltage requirements of the target transmission mode include: the voltage of the branch to be turned on is greater than the voltage of the battery pack branch in the battery module that was last turned on with the energy transmission system, and the voltage difference is greater than the second voltage difference.

13. A battery energy status determination device, characterized in that: The device comprises: a branch determination module, configured to determine, based on branch states of multiple battery pack branches in a battery module, multiple candidate battery pack branches whose branch states are normal from the multiple battery pack branches; determine, from the multiple candidate battery pack branches, at least one first branch that is conductive with an energy transmission system and at least one second branch that is not conductive with the energy transmission system; determine, based on voltages of the at least one first branch and the at least one second branch, and an energy transmission mode of the battery module, at least one target battery pack branch from the multiple candidate battery pack branches; the at least one target battery pack branch includes at least one battery pack branch that is not conductive with the energy transmission system of the battery module; the at least one target battery pack branch includes the first branch and a second branch of the second branch that satisfies a voltage relationship with the first branch under the energy transmission mode; A state estimation module is used to determine the energy state of the battery module according to the remaining power of the at least one target battery pack branch.

14. A battery management system, characterized in that: The method comprises a memory and a processor, wherein the memory stores a computer program, and is characterized in that when the processor executes the computer program, the steps of the method according to any one of claims 1 to 12 are implemented.

15. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 12 are implemented.

16. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 12 are implemented.

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