Multi-pack parallel charging and discharging control method and device for battery packs

Abstract

The invention relates to the technical field of batteries, and discloses a multi-pack parallel charging and discharging control method and device for battery packs, and the method comprises the steps: obtaining the current state information of each battery pack in a parallel total pack which is formed by connecting a target battery pack with at least one other battery pack in parallel; in response to a preset starting signal of the target battery pack, determining a charging and discharging mode of the target battery pack according to the preset starting signal; performing charge-discharge sorting on the target battery pack based on the charge-discharge mode of the target battery pack and the current state information of all the battery packs, and controlling the target battery pack to enter the charge-discharge mode; and calculating total pack charging and discharging power data of the target battery pack, and performing charging and discharging control on the target battery pack based on the total pack charging and discharging power data. The method can overcome the defects of parallel charging and discharging of a plurality of existing independent battery packs, has the advantages of high control efficiency and low cost, can guarantee safe charging and discharging of the parallel battery packs, and further improves the user experience.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and in particular to a method and device for controlling the parallel charging and discharging of multiple battery packs. Background Art

[0002] With the global shift to new energy for automobiles, electric motorcycles (also known as electric motorcycles) have also ushered in changes. Compared with electric cars, electric motorcycles have not formed a unified standard in the industry, that is, each manufacturer reserves different space for electric motorcycle batteries, and car manufacturers always need to find battery manufacturers to customize batteries. Specifically, battery manufacturers try to launch battery packs with different voltage platforms and smaller volumes. Customers can choose to network multiple battery packs according to their needs to meet their endurance requirements. For customers, they can choose different endurance packages, and they can also network the battery packs at will during use.

[0003] Currently, for the control of parallel charging and discharging of multiple independent battery packs, the existing technology adds a high-power control board outside the battery pack to achieve charge and discharge control of the battery pack. However, the additional high-power control board needs to be developed by a special factory, such as a battery factory or an automobile factory, which will greatly increase the charge and discharge cost and space occupied by the battery pack, and has the problems of high control cost and low efficiency, making it difficult to achieve reasonable charge and discharge of the battery pack, which seriously affects the safe use of users. Summary of the invention

[0004] In view of this, the present invention provides a method and device for controlling parallel charging and discharging of multiple battery packs to solve the problems of low control efficiency and high cost of existing parallel charging and discharging of multiple independent battery packs, difficulty in achieving safe and effective charging and discharging control of the battery packs, and further affecting the user experience.

[0005] In a first aspect, the present invention provides a method for controlling the parallel charging and discharging of multiple battery packs, the method comprising:

[0006] Obtaining current status information of each battery pack in a parallel total pack, wherein the parallel total pack is formed by connecting a target battery pack in parallel with at least one other battery pack;

[0007] In response to a preset start signal of the target battery pack, determining a charge and discharge mode of the target battery pack according to the preset start signal;

[0008] Based on the charge and discharge mode of the target battery pack and the current status information of all battery packs, the target battery pack is charged and discharged in a sequence, and the target battery pack is controlled to enter the charge and discharge mode;

[0009] Calculate the total pack charge and discharge power data of the target battery pack, and control the charge and discharge of the target battery pack based on the total pack charge and discharge power data, wherein the total pack charge and discharge power data is determined according to the charge and discharge power data of all battery packs in the parallel total pack.

[0010] The multi-pack parallel charge and discharge control method of the battery pack of the present invention, after determining its charge and discharge mode through the preset start signal of the target battery pack, firstly performs charge and discharge sequencing to determine the charge and discharge order of each battery pack; after the charge and discharge sequencing, the target battery pack is controlled to enter the charge and discharge mode, the total pack charge and discharge power data of the target battery pack is calculated and the charge and discharge control is performed based on the data, which can reduce the control cost of parallel charging and discharging of multiple independent battery packs, help to improve the control efficiency, ensure the safe charging and discharging of the parallel battery packs, and thus enhance the user experience.

[0011] In an optional implementation, the preset start signal includes a charging signal and a discharging signal, wherein the charging signal is generated after the battery pack establishes a communication connection with a preset charging device, and the discharging signal is generated after the battery pack establishes a connection with a preset discharging device; determining the charging and discharging mode of the target battery pack according to the preset start signal includes:

[0012] If the preset start signal is a charging signal, determining that the charge and discharge mode of the target battery pack is a charging mode;

[0013] If the preset start signal is a discharge signal, the charge and discharge mode of the target battery pack is determined to be a discharge mode.

[0014] The present invention determines the corresponding charge and discharge mode by the signal type of the preset start signal of the target battery pack, which can ensure the accurate identification of the charge and discharge mode and help to improve the subsequent precise control of the target battery pack.

[0015] In an optional implementation, if the charge and discharge mode is a charging mode, the target battery pack is charged and discharged in a sorting manner based on the charge and discharge mode of the target battery pack and the current state information of all battery packs, and the target battery pack is controlled to enter the charge and discharge mode, including:

[0016] In a first preset cycle, based on current state information of all battery packs, all battery packs to be charged whose charge and discharge modes are charging modes are obtained from the parallel total pack to obtain a first charging set;

[0017] The first charging set is filtered based on a preset charging condition to obtain a second charging set, where the preset charging condition is a charging restriction condition of the battery pack, and the charging restriction condition at least includes that the battery pack is forced to exit the charging mode, the battery pack position is invalid, the battery pack communication is abnormal, and the battery pack is in a charging protection state;

[0018] Determine the lowest voltage according to the current state information of each battery pack to be charged in the second charging set, and calculate a first voltage difference between the current voltage corresponding to the target battery pack and the lowest voltage;

[0019] If the first voltage difference is 0, it is determined that the target battery pack belongs to the low-voltage pack parallel situation, and the target battery pack is controlled to enter the charging mode after delay filtering processing; wherein, the low-voltage pack parallel situation means that when the target battery pack is incorporated into the parallel total pack, the current voltage corresponding to the target battery pack is the minimum voltage on the parallel total pack;

[0020] If the first voltage difference is not 0, it is determined that the target battery pack does not belong to the low-voltage pack parallel situation, and it is judged whether the first voltage difference is greater than the first preset voltage difference threshold; if the first voltage difference is not greater than the first preset voltage difference threshold, the target battery pack is controlled to enter the charging mode after delay filtering; if the first voltage difference is greater than the first preset voltage difference threshold, it returns to the step of responding to the preset start signal of the target battery pack and determining the charge and discharge mode of the target battery pack according to the preset start signal.

[0021] In the charging mode, the present invention sorts all the battery packs to be charged in the current parallel total pack, filters out the battery packs that do not meet the charging conditions based on the charging restriction conditions, and then judges the charging sorting of the target battery pack based on whether the target battery pack belongs to a low-voltage pack in parallel. After the target battery pack meets the relevant charging conditions, it controls it to enter the charging mode after delay filtering processing, which can ensure the charging safety of the target battery pack.

[0022] In an optional implementation, if the charge and discharge mode is the discharge mode, the target battery pack is charged and discharged in a sequence based on the charge and discharge mode of the target battery pack and the current state information of all battery packs, and the target battery pack is controlled to enter the charge and discharge mode, including:

[0023] In a second preset cycle, based on current state information of all battery packs, all battery packs to be discharged whose charge and discharge modes are discharge modes are obtained from the parallel total pack to obtain a first discharge set;

[0024] The first discharge set is filtered based on a preset discharge condition to obtain a second discharge set, where the preset discharge condition is a discharge restriction condition of the battery pack, and the discharge restriction condition at least includes a situation where the battery pack is in a mid-parallel connection, a situation where the battery pack has a fault exit, a situation where the battery pack has a forced exit from a discharge mode, an invalid battery pack position, an abnormal battery pack communication, and a battery pack in a discharge protection state;

[0025] Determine the highest voltage according to the current state information of each battery pack to be discharged in the second discharge set, and calculate the second voltage difference between the current voltage corresponding to the target battery pack and the highest voltage;

[0026] Determine whether the target battery pack belongs to the large current dynamic parallel situation, wherein the large current dynamic parallel situation means that when the target battery pack is incorporated into the parallel total package, the current current corresponding to the parallel total package is greater than the preset threshold current;

[0027] When the target battery pack is not in a high-current dynamic parallel connection state, determining whether the second voltage difference is greater than a second preset voltage difference threshold; if the second voltage difference is not greater than the second preset voltage difference threshold, controlling the target battery pack to enter a discharge mode after delay filtering processing is performed on the target battery pack; if the second voltage difference is greater than the second preset voltage difference threshold, returning to the step of responding to a preset start signal of the target battery pack and determining a charge and discharge mode of the target battery pack according to the preset start signal;

[0028] When the target battery pack belongs to the large current dynamic parallel situation, at least one second battery pack that is discharging in the parallel total pack is obtained, and the third voltage difference between the target battery pack and each second battery pack is calculated respectively, and each third voltage difference is determined whether it is greater than the second preset voltage difference threshold, wherein the current current of the second battery pack in the parallel total pack is greater than the preset threshold current; if all the third voltage differences are greater than the second preset voltage difference threshold, the target battery pack is controlled to enter the discharge mode after delay filtering; if there is at least one third voltage difference that is not greater than the second preset voltage difference threshold, the step of returning to respond to the preset start signal of the target battery pack and determining the charge and discharge mode of the target battery pack according to the preset start signal is returned.

[0029] The present invention sorts all battery packs to be discharged in the current parallel total pack in the discharge mode, filters out the battery packs that do not meet the discharge requirements based on the discharge restriction conditions, and then judges the discharge order of the target battery pack based on whether the target battery pack belongs to a large current dynamic parallel situation. After the target battery pack meets the relevant sorting conditions, it is controlled to enter the discharge mode after delay filtering processing, which can ensure the discharge safety of the target battery pack.

[0030] In an optional implementation, calculating the total pack charge and discharge power data of the target battery pack includes:

[0031] Detecting the current charge and discharge current of the parallel total package, where the current charge and discharge current is the sum of the charge and discharge currents of all battery packs in the parallel total package;

[0032] Determine whether the current charge and discharge current is less than a first preset current threshold;

[0033] When the current charge and discharge current is less than the first preset current threshold, the initial total package charge and discharge power data is calculated, and the initial total package charge and discharge power data is determined as the total package charge and discharge power data of the target battery pack, wherein the initial total package charge and discharge power data is the maximum charge and discharge power data of the battery pack that has entered the charge and discharge mode, and the charge and discharge power data corresponding to the battery pack that has entered the charge and discharge mode is obtained by looking up the preset charge and discharge power data table according to the current temperature and charge state of the battery pack;

[0034] When the current charge and discharge current is not less than a first preset current threshold, the charge and discharge power data of the battery pack that has entered the charge and discharge mode and the charge and discharge capacity of the battery pack are calculated, and the total charge and discharge power data of the target battery pack is determined based on the charge and discharge power data of all battery packs and the corresponding charge and discharge capacities, wherein the charge and discharge capacity of the battery pack is obtained based on the ratio of the charge and discharge current of the battery pack to the total charge and discharge current of all battery packs that have entered the charge and discharge mode.

[0035] The present invention calculates the total pack charge and discharge power data of the target battery pack according to the relationship between the current charge and discharge current of the parallel total pack and the first preset current threshold value, which can ensure the calculation accuracy of the total pack charge and discharge power data, thereby helping to improve the control efficiency of the target battery pack and ensure the charge and discharge safety of the target battery pack.

[0036] In an optional implementation, determining the total pack charge and discharge power data of the target battery pack based on the charge and discharge power data of all battery packs and the corresponding charge and discharge capabilities includes:

[0037] For all battery packs including the target battery pack, the ratio of each battery pack is calculated respectively, where the ratio is the value obtained by comparing the charge and discharge power data of a single battery pack with its corresponding charge and discharge capacity;

[0038] The smallest ratio is selected from multiple ratios to obtain the total charge and discharge power data of the target battery pack.

[0039] The present invention obtains the total pack charge and discharge power data of the target battery pack through the charge and discharge power data of each battery pack and the minimum ratio of its charge and discharge capacity, which can ensure the charge and discharge safety of each battery pack in the parallel total pack.

[0040] In an optional implementation, after obtaining the total pack charge and discharge power data of the target battery pack, the multi-pack parallel charge and discharge control method of the battery pack further includes:

[0041] Filter the single-pack charge and discharge power data with the largest value from the charge and discharge power data of multiple battery packs;

[0042] When the total package charge and discharge power data is less than the preset ratio of the single package charge and discharge power data and lasts for a first preset time, if the total package charge and discharge power data is equal to the ratio of the target battery pack, control the target battery pack to forcibly exit the charge and discharge mode;

[0043] If the total pack charge and discharge power data is not less than a preset ratio of the single pack charge and discharge power data or does not last for a preset time, or the total pack charge and discharge power data is not equal to the ratio of the target battery pack, the target battery pack will continue to be charged and discharged based on the total pack charge and discharge power data.

[0044] The present invention designs a relationship determination process between the total package charge and discharge power data and the charge and discharge power data of a single package with the largest value among the charge and discharge power data of multiple battery packs. This can verify the validity of the total package charge and discharge power data and control the target battery pack to forcibly exit the charge and discharge mode when the requirements are not met, thereby greatly ensuring the charge and discharge safety of each battery pack on the parallel total package.

[0045] In an optional embodiment, the method for controlling the charging and discharging of multiple battery packs in parallel further includes:

[0046] In each update cycle of the charge and discharge capability of the target battery pack, statistics are collected on the current situation of each battery pack entering or exiting the charge and discharge mode;

[0047] If any battery pack enters the charge and discharge mode, the total pack charge and discharge power data currently calculated for the target battery pack is maintained, and the step of detecting the current charge and discharge current of the parallel total pack is returned until the new total pack charge and discharge power data for the target battery pack is calculated;

[0048] If any battery pack exits the charge and discharge mode, the step of detecting the current charge and discharge current of the parallel total pack is returned, and before the new total pack charge and discharge power data of the target battery pack is calculated, the maximum value in the corresponding charge and discharge power data of each battery pack in the parallel total pack is determined as the current total pack charge and discharge power data of the target battery pack.

[0049] The present invention adopts a periodic statistical method to obtain the charging and discharging conditions of each battery in each update cycle of the charging and discharging capacity of the target battery pack. When other battery packs enter or exit the current charging and discharging mode, a corresponding calculation process for the total pack charging and discharging power data of the target battery pack is designed, which can ensure the generalization and accuracy of the total pack charging and discharging power data, thereby improving the charging and discharging control efficiency of the target battery pack.

[0050] In an optional implementation, if the charge and discharge mode is a charging mode, after obtaining the total charge and discharge power data of the target battery pack, the multi-pack parallel charge and discharge control method of the battery pack further includes:

[0051] Obtain the parallel circulation current of the parallel package;

[0052] The total package charge and discharge power data of the target battery pack is updated based on the parallel circulation current to obtain updated total package charge and discharge power data.

[0053] The present invention takes into account the parallel circulating current of the parallel total pack when the target battery pack is in the charging mode, and updates the total pack charge and discharge power data of the target battery pack based on the parallel circulating current, thereby ensuring the calculation accuracy of the total pack charge and discharge power data.

[0054] In an optional implementation, the charge and discharge control of the target battery pack is performed based on the total pack charge and discharge power data, including:

[0055] After the communication master package uploads the total package charge and discharge power data to the central control or preset charging device, the central control or preset charging device controls the charge and discharge of the target battery pack based on the total package charge and discharge power data; wherein, the communication master package is determined based on the bus position information in the current status information of each battery pack in the parallel total package.

[0056] The present invention communicates with the central control or a preset charging device through a communication main package, which can improve communication efficiency and further enhance the charge and discharge control of the target battery pack.

[0057] In an optional implementation, if the charge and discharge mode is a discharge mode, the method for controlling the parallel charge and discharge of multiple battery packs further includes:

[0058] When energy feedback is detected in the discharge mode, the current feedback current of the parallel package is obtained;

[0059] Determining whether the current feedback current is less than a second preset current threshold;

[0060] When the current feedback current is less than the second preset current threshold, the initial total package feedback power data is calculated, and the initial total package feedback power data is determined as the total package charging power state of the target battery pack, wherein the initial total package feedback power data is the maximum feedback power data in the battery pack, and the feedback power data corresponding to the battery pack is obtained by looking up the preset feedback power data table according to the current temperature and charge state of the battery pack;

[0061] When the current feedback current is not less than a second preset current threshold and lasts for a second preset time, the charging power state of each battery pack and the charging capacity of the battery pack are calculated, and the total pack feedback power data of the target battery pack is determined based on the charging power states and charging capacities of all battery packs, wherein the charging capacity of the battery pack is obtained according to the ratio of the feedback current of the battery pack to the total charging current of all battery packs that have entered the charging mode;

[0062] The target battery pack is charged and controlled based on the total pack feedback power data.

[0063] When the target battery pack is in the discharge mode, the present invention designs a calculation process of the total package feedback power data corresponding to the energy feedback in consideration of the energy feedback situation, and controls the charging of the target battery pack based on the total package feedback power data, thereby realizing precise charging control of the target battery pack.

[0064] In an optional embodiment, the method for controlling the charging and discharging of multiple battery packs in parallel further includes:

[0065] If the target battery pack is forced to exit the charging mode, when the charging and discharging power data of the target battery pack is greater than the charging and discharging power data of other battery packs in the parallel total pack, or after the charging signal is restarted and responds to the charging signal again, the target battery pack is controlled to enter the charging mode;

[0066] If the target battery pack is forced to exit the discharge mode, the discharge signal is restarted, and the target battery pack is controlled to enter the discharge mode after responding to the discharge signal again.

[0067] The present invention takes into account the prerequisite for the target battery pack to re-enter the corresponding charge / discharge mode when the target battery pack is forced to exit the charge / discharge mode, and can ensure comprehensive and effective charge / discharge control of the target battery pack.

[0068] In a second aspect, the present invention provides a multi-pack parallel charging and discharging control device for a battery pack, the device comprising:

[0069] An information acquisition module, used to acquire current status information of each battery pack in a parallel total pack, wherein the parallel total pack is formed by connecting a target battery pack in parallel with at least one other battery pack;

[0070] A mode determination module, configured to respond to a preset start signal of a target battery pack and determine a charge and discharge mode of the target battery pack according to the preset start signal;

[0071] A charge and discharge sequencing module, used to perform charge and discharge sequencing on the target battery pack based on the charge and discharge mode of the target battery pack and the current status information of all battery packs, and control the target battery pack to enter the charge and discharge mode;

[0072] The charge and discharge control module is used to calculate the total pack charge and discharge power data of the target battery pack, and to control the charge and discharge of the target battery pack based on the total pack charge and discharge power data, wherein the total pack charge and discharge power data is determined according to the charge and discharge power data of all battery packs in the parallel total pack.

[0073] The device for controlling parallel charging and discharging of multiple battery packs of the present invention determines the charging and discharging mode of the target battery pack through a preset starting signal of the target battery pack, performs charging and discharging sorting to determine the charging and discharging order of each battery pack, controls the target battery pack to enter the corresponding charging and discharging mode, calculates the total pack charging and discharging power data of the target battery pack and performs charging and discharging control based on the data, which can greatly reduce the control cost of parallel charging and discharging of multiple independent battery packs, improves the control efficiency, ensures the safe charging and discharging of the parallel battery packs, and enhances the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0075] Figure 1 is a flow chart of a method for controlling parallel charging and discharging of multiple battery packs according to an embodiment of the present invention;

[0076] Figure 2 is a flow chart of another method for controlling parallel charging and discharging of multiple battery packs according to an embodiment of the present invention;

[0077] Figure 3 This is a schematic diagram of the parallel charging sequence of multiple packs;

[0078] Figure 4 It is a schematic diagram of the discharge sequencing of multiple packages in parallel;

[0079] Figure 5 This is a schematic diagram of SOP calculation for charging multiple packs in parallel;

[0080] Figure 6 This is a schematic diagram of SOP calculation for multi-pack parallel discharge;

[0081] Figure 7 It is a structural block diagram of a multi-pack parallel charge and discharge control device for battery packs according to an embodiment of the present invention. DETAILED DESCRIPTION

[0082] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0083] In this embodiment, a method for controlling the parallel charging and discharging of multiple battery packs is provided. Figure 1 FIG. 1 is a flow chart of a method for controlling parallel charging and discharging of multiple battery packs according to an embodiment of the present invention. Figure 1 As shown, the process includes the following steps:

[0084] Step S101, obtaining current status information of each battery pack in a parallel total pack, wherein the parallel total pack is formed by a target battery pack and at least one other battery pack in parallel.

[0085] In this embodiment, the specific content of the current status information of the battery pack and the method of obtaining the information are not limited here. For example, the current status information includes the current, voltage, temperature, and position (i.e., the area where the battery is stored, also known as the storage location of the battery) of the battery pack; through the analog front end (Analog Front End, AFE) and analog to digital converter module (Analog to Digital Converter, AD module) of the battery management system. It should be explained that AFE in the battery management system usually refers to the "battery sampling chip", which is mainly used to collect parameters such as the voltage and temperature of the battery cell; the AD module is responsible for converting the analog signal into a digital signal for further processing by the microcontroller or processor.

[0086] Step S102 , in response to a preset start signal of the target battery pack, determining a charge and discharge mode of the target battery pack according to the preset start signal.

[0087] In this embodiment, the signal type of the preset start signal determines the current charge / discharge mode of the target battery pack, and the specific signal type can be determined according to the actual connection relationship of the target battery pack.

[0088] Step S103 , based on the charge and discharge mode of the target battery pack and the current status information of all battery packs, the target battery pack is charged and discharged in a sequence, and the target battery pack is controlled to enter the charge and discharge mode.

[0089] In this embodiment, the charge and discharge sequencing of the target battery pack is essentially to determine the charging or discharging order of the battery pack, following the sequencing logic of high-voltage packs discharging first and low-voltage packs charging first to independently decide whether the target battery pack should enter the charging or discharging mode.

[0090] Step S104, calculating the total pack charge and discharge power data of the target battery pack, and controlling the charge and discharge of the target battery pack based on the total pack charge and discharge power data, wherein the total pack charge and discharge power data is determined according to the charge and discharge power data of all battery packs in the parallel total pack.

[0091] In this embodiment, the charge and discharge power data represents the SOP (State of Power) of the target battery pack in the charge or discharge mode.

[0092] The method for controlling parallel charging and discharging of multiple battery packs of an embodiment of the present invention determines the charging and discharging mode of the target battery pack through a preset start signal of the target battery pack, and then performs charging and discharging sequencing to determine the charging and discharging order of each battery pack; after the charging and discharging sequencing, the target battery pack is controlled to enter the charging and discharging mode, and the total pack charging and discharging power data of the target battery pack is calculated and charging and discharging control is performed based on the data, which can reduce the control cost of parallel charging and discharging of multiple independent battery packs, help improve the charging and discharging control efficiency of the battery pack, ensure the safe charging and discharging of the parallel battery packs, and thus enhance the user experience.

[0093] In this embodiment, a method for controlling the parallel charging and discharging of multiple battery packs is provided. Figure 2 FIG. 1 is a flow chart of another method for controlling parallel charging and discharging of multiple battery packs of an embodiment of the present invention. Figure 2 As shown, the process includes the following steps:

[0094] Step S201, obtaining the current status information of each battery pack in the parallel total pack, wherein the parallel total pack is formed by the target battery pack and at least one other battery pack in parallel. Figure 1 Step S101 of the illustrated embodiment will not be described in detail here.

[0095] Step S202 , in response to a preset start signal of the target battery pack, determining a charge and discharge mode of the target battery pack according to the preset start signal.

[0096] In this embodiment, the preset start signal includes a charging signal and a discharging signal, wherein the charging signal is generated after the battery pack establishes a communication connection with the preset charging device, and the discharging signal is generated after the battery pack establishes a connection with the preset discharging device. It should be noted that the discharge signal of this embodiment is generated after the battery pack establishes a connection with the preset discharging device, that is, a hard-wired connection. For example, a discharge signal can be generated once the battery pack is inserted into the preset discharging device; in addition, the specific types of the preset charging device and the preset discharging device of this embodiment can be adaptively set according to actual needs. For example, the preset charging device is a charging pile, and its corresponding charging signal is an intelligent charging signal; the preset discharging device is a car, and its corresponding discharge signal is a key signal, that is, once the key is inserted into the vehicle and the key signal is detected, the discharge sequence can be performed. This is only an exemplary description.

[0097] Specifically, determining the charge and discharge mode of the target battery pack according to the preset start signal in the above step S202 includes:

[0098] Step S2021: if the preset start signal is a charging signal, determining that the charge and discharge mode of the target battery pack is a charging mode.

[0099] Step S2022: if the preset start signal is a discharge signal, determining that the charge and discharge mode of the target battery pack is a discharge mode.

[0100] In the embodiment of the present invention, the corresponding charge and discharge mode is determined by the signal type of the preset start signal of the target battery pack, which can ensure the accurate identification of the charge and discharge mode and improve the precise control of the target battery pack.

[0101] Step S203 , based on the charge and discharge mode of the target battery pack and the current status information of all battery packs, the target battery pack is sorted for charge and discharge, and the target battery pack is controlled to enter the charge and discharge mode.

[0102] In this embodiment, if the charge and discharge mode is the charging mode, the target battery pack is charged and discharged in a sorting manner based on the charge and discharge mode of the target battery pack and the current state information of all battery packs in the above step S203, including:

[0103] Step A1, within a first preset cycle, based on current status information of all battery packs, all battery packs to be charged whose charge and discharge mode is a charging mode are obtained from the parallel total pack to obtain a first charging set.

[0104] In this embodiment, the specific value of the first preset period is not limited here, and can be adaptively adjusted according to actual needs. For example, the first preset period is 100 ms, which is only used as an exemplary description.

[0105] Step A2, filtering the first charging set based on preset charging conditions to obtain a second charging set, wherein the preset charging conditions are charging restriction conditions of the battery pack, and the charging restriction conditions at least include that the battery pack is forced to exit the charging mode, the battery pack position is invalid, the battery pack communication is abnormal, and the battery pack is in a charging protection state.

[0106] It should be noted that the specific content of the charging restriction conditions in this embodiment will mark the corresponding abnormal situation when the battery pack has a corresponding abnormality.

[0107] Step A3, determining the lowest voltage according to the current state information of each battery pack to be charged in the second charging set, and calculating a first voltage difference between the current voltage corresponding to the target battery pack and the lowest voltage.

[0108] Step A4, if the first voltage difference is 0, determine whether the target battery pack belongs to the low-voltage parallel pack situation, and control the target battery pack to enter the charging mode after delay filtering processing; wherein, the low-voltage parallel pack situation means that when the target battery pack is incorporated into the parallel total pack, the current voltage corresponding to the target battery pack is the minimum voltage on the parallel total pack.

[0109] Step A5, if the first voltage difference is not 0, it is determined that the target battery pack does not belong to the low-voltage pack parallel situation, and it is judged whether the first voltage difference is greater than the first preset voltage difference threshold; if the first voltage difference is not greater than the first preset voltage difference threshold, the target battery pack is controlled to enter the charging mode after delay filtering; if the first voltage difference is greater than the first preset voltage difference threshold, it returns to respond to the preset start signal of the target battery pack, and determines the charge and discharge mode of the target battery pack according to the preset start signal.

[0110] In this embodiment, the specific value of the first preset pressure difference threshold can be adaptively adjusted according to actual needs and is not limited here.

[0111] It should be noted that in the present embodiment, the delayed filtering process for the target battery pack may introduce a certain time delay, such as a delay of 1S, to achieve a filtering effect for the target battery pack.

[0112] In the embodiment of the present invention, in the charging mode, all battery packs to be charged in the current parallel total pack are sorted, and after the battery packs that do not meet the charging requirements are filtered out based on the charging restriction conditions, the charging order of the target battery pack is determined based on whether the target battery pack belongs to a low-voltage pack in parallel. After the target battery pack meets the relevant charging conditions, it is controlled to enter the charging mode after delay filtering processing, thereby ensuring the charging safety of the target battery pack.

[0113] In this embodiment, if the charge and discharge mode is the discharge mode, the target battery pack is charged and discharged in a sequence based on the charge and discharge mode of the target battery pack and the current state information of all battery packs in the above step S203, including:

[0114] Step B1, within a second preset period, based on the current state information of all battery packs, all battery packs to be discharged whose charging and discharging mode is a discharge mode are obtained from the parallel total pack to obtain a first discharge set.

[0115] In this embodiment, the specific value within the second preset period is not limited here, and can be adaptively adjusted according to actual needs. For example, the second preset period is 50 ms, which is only used as an exemplary description.

[0116] Step B2, filtering the first discharge set based on the preset discharge condition to obtain the second discharge set, the preset discharge condition is the discharge restriction condition of the battery pack, and the discharge restriction condition at least includes the battery pack being in parallel midway, the battery pack having a fault exit, the battery pack having a forced exit from the discharge mode, the battery pack position being invalid, the battery pack communication being abnormal, and the battery pack being in a discharge protection state.

[0117] It should be noted that the specific content of the discharge restriction condition in this embodiment will mark the corresponding abnormal situation when the corresponding abnormality occurs in the battery pack.

[0118] Step B3, determining the highest voltage according to the current state information of each battery pack to be discharged in the second discharge set, and calculating a second voltage difference between the current voltage corresponding to the target battery pack and the highest voltage.

[0119] Step B4, determining whether the target battery pack belongs to a large current dynamic parallel situation, wherein the large current dynamic parallel situation means that when the target battery pack is incorporated into a parallel total package, the current current corresponding to the parallel total package is greater than a preset threshold current.

[0120] In this embodiment, the specific value of the preset threshold current is not limited here and can be adaptively adjusted according to actual needs.

[0121] Step B5, when the target battery pack does not belong to the large current dynamic parallel situation, determine whether the second voltage difference is greater than the second preset voltage difference threshold; if the second voltage difference is not greater than the second preset voltage difference threshold, then control the target battery pack to enter the discharge mode after delay filtering processing; if the second voltage difference is greater than the second preset voltage difference threshold, then return to respond to the preset start signal of the target battery pack, and determine the charge and discharge mode of the target battery pack according to the preset start signal.

[0122] In this embodiment, the specific value of the second preset pressure difference threshold can be adaptively adjusted according to actual needs; the relevant content of the delay filtering process is referred to the above, and will not be repeated here.

[0123] Step B6, when the target battery pack belongs to the large current dynamic parallel situation, obtain at least one second battery pack that is discharging in the parallel total pack, calculate the third voltage difference between the target battery pack and each second battery pack respectively, and judge whether each third voltage difference is greater than the second preset voltage difference threshold, wherein the current current of the second battery pack in the parallel total pack is greater than the preset threshold current; if all the third voltage differences are greater than the second preset voltage difference threshold, then the target battery pack is controlled to enter the discharge mode after delay filtering processing; if there is at least one third voltage difference that is not greater than the second preset voltage difference threshold, then return to the step of responding to the preset start signal of the target battery pack and determining the charge and discharge mode of the target battery pack according to the preset start signal.

[0124] In the embodiment of the present invention, in the discharge mode, all battery packs to be discharged in the current parallel total pack are sorted, and after filtering out the battery packs that do not meet the discharge requirements based on the discharge restriction conditions, the discharge sorting of the target battery pack is determined based on whether the target battery pack belongs to a large current dynamic parallel situation, and after the target battery pack meets the relevant sorting conditions, it is controlled to enter the discharge mode after delay filtering processing, thereby ensuring the discharge safety of the target battery pack.

[0125] Step S204, calculate the total pack charge and discharge power data of the target battery pack, and control the charge and discharge of the target battery pack based on the total pack charge and discharge power data, wherein the total pack charge and discharge power data is determined according to the charge and discharge power data of all battery packs in the parallel total pack.

[0126] Specifically, the above step S204 includes:

[0127] Step S2041, detecting the current charge and discharge current of the parallel total pack, wherein the current charge and discharge current is the sum of the charge and discharge currents of all battery packs in the parallel total pack.

[0128] In this embodiment, the specific detection method of the current charging and discharging current is not limited here, and can be obtained according to a conventional current detection method in the art.

[0129] Step S2042, determining whether the current charge and discharge current is less than a first preset current threshold.

[0130] In this embodiment, the specific value of the first preset current threshold is adaptively adjusted according to actual needs.

[0131] Step S2043, when the current charge and discharge current is less than the first preset current threshold, calculate the initial total package charge and discharge power data, and determine the initial total package charge and discharge power data as the total package charge and discharge power data of the target battery pack, wherein the initial total package charge and discharge power data is the maximum charge and discharge power data in the battery pack that has entered the charge and discharge mode, and the charge and discharge power data corresponding to the battery pack that has entered the charge and discharge mode is obtained by looking up the preset charge and discharge power data table based on the current temperature and charge state of the battery pack.

[0132] In practical applications, the charging SOP table and discharging SOP table of the temperature, state of charge and corresponding power state of the battery pack under charging or discharging state can be obtained through offline calibration, that is, the preset charging and discharging power data table of this embodiment.

[0133] Step S2044, when the current charge and discharge current is not less than the first preset current threshold, calculate the charge and discharge power data of the battery pack that has entered the charge and discharge mode and the charge and discharge capacity of the battery pack, and determine the total charge and discharge power data of the target battery pack based on the charge and discharge power data of all battery packs and the corresponding charge and discharge capacity, wherein the charge and discharge capacity of the battery pack is obtained based on the ratio of the charge and discharge current of the battery pack to the total charge and discharge current of all battery packs that have entered the charge and discharge mode.

[0134] Specifically, in the above step S2044, the total pack charge and discharge power data of the target battery pack is determined based on the charge and discharge power data of all battery packs and the corresponding charge and discharge capabilities, including:

[0135] Step C1, for all battery packs including the target battery pack, the ratio of each battery pack is calculated respectively, wherein the ratio is a value obtained by comparing the charge and discharge power data of a single battery pack with its corresponding charge and discharge capacity.

[0136] In this embodiment, the charge and discharge power data of the battery pack is obtained by looking up a table; the charge and discharge capacity of the battery pack is calculated based on the current charge and discharge status of each battery pack.

[0137] Step C2, selecting the smallest ratio from multiple ratios to obtain total pack charge and discharge power data of the target battery pack.

[0138] In the embodiment of the present invention, the total pack charge and discharge power data of the target battery pack is obtained by using the charge and discharge power data of each battery pack and the minimum ratio of their charge and discharge capabilities, which can ensure the charge and discharge safety of each battery pack in the parallel total pack.

[0139] It should be noted that in order to ensure the total package charge and discharge power data of the target battery pack, that is, the accuracy of the total package charge / discharge SOP, a verification process for the total package charge / discharge SOP is also designed in this embodiment to ensure its calculation quality. Specifically, the multi-pack parallel charge and discharge control method of the battery pack of this embodiment also includes:

[0140] Step D1, selecting the single-pack charge and discharge power data with the largest value from the charge and discharge power data of multiple battery packs.

[0141] Step D2, when the total pack charge and discharge power data is less than the preset ratio of the single pack charge and discharge power data and lasts for a first preset time, if the total pack charge and discharge power data is equal to the ratio of the target battery pack, the target battery pack is controlled to forcibly exit the charge and discharge mode.

[0142] In this embodiment, specific values ​​of the preset ratio and the first preset time can be adaptively set according to actual needs. For example, the preset ratio is 20% and the first preset time is 2 minutes, which is only an exemplary description.

[0143] Step D3, when the total package charge and discharge power data is not less than the preset ratio of the single package charge and discharge power data or does not last for a preset time, or the total package charge and discharge power data is not equal to the ratio of the target battery pack, continue to control the charge and discharge of the target battery pack based on the total package charge and discharge power data.

[0144] In the embodiment of the present invention, a process for determining the relationship between the total package charge and discharge power data and the charge and discharge power data of a single package with the largest value is designed to verify the validity of the total package charge and discharge power data, and to control the target battery pack to forcibly exit the charge and discharge mode when the requirements are not met, thereby greatly ensuring the charge and discharge safety of each battery pack on the parallel total package.

[0145] It should be noted that the present embodiment adopts a periodic statistical method. After calculating the total charge / discharge SOP of the target battery pack, a corresponding design is also provided to detect whether there are other battery packs entering or exiting during the charge / discharge capacity update cycle of the target battery pack, so as to update the total charge / discharge SOP obtained. Specifically, the multi-pack parallel charge / discharge control method of the present embodiment also includes:

[0146] Step E1, within each update cycle of the charge and discharge capability of the target battery pack, statistics are collected on the current status of each battery pack entering or exiting the charge and discharge mode.

[0147] In this embodiment, the specific value of the update period is adaptively set according to actual needs, such as the update period is 3S.

[0148] Step E2, if any battery pack enters the charge and discharge mode, maintain the total pack charge and discharge power data currently calculated for the target battery pack, and return to the step of detecting the current charge and discharge current of the parallel total pack until the new total pack charge and discharge power data of the target battery pack is calculated.

[0149] Step E3, if any battery pack exits the charge and discharge mode, return to the step of detecting the current charge and discharge current of the parallel total pack, and before the calculation of the new total pack charge and discharge power data of the target battery pack is completed, determine the maximum value of the corresponding charge and discharge power data of each battery pack in the parallel total pack as the current total pack charge and discharge power data of the target battery pack.

[0150] It should be noted that, in this embodiment, when the battery pack enters or exits the charge and discharge mode, it can be determined accordingly through the message status of the corresponding battery pack on the communication bus of the parallel package.

[0151] The embodiment of the present invention designs a corresponding calculation process for the total pack charge and discharge power data of the target battery pack when other battery packs enter or exit the current charge and discharge mode, which can ensure the generalization and accuracy of the total pack charge and discharge power data, thereby improving the charge and discharge control efficiency of the target battery pack.

[0152] It should be noted that after calculating the total package charge / discharge SOP of the target battery pack, if the target battery pack is in charging mode, the circulation situation needs to be considered, and the total package charging SOP needs to be updated based on the circulation current. Therefore, after obtaining the total package charge and discharge power data of the target battery pack in charging mode, the multi-package parallel charge and discharge control method of the battery pack of this embodiment also includes: obtaining the parallel circulation current of the parallel total package; updating the total package charge and discharge power data of the target battery pack based on the parallel circulation current to obtain the updated total package charge and discharge power data. It should be explained that the circulation current is the discharge of the high-voltage package to the low-voltage package. Each battery pack can detect whether it is currently in a discharge or charging state. If the charger is plugged in and a battery pack is discharging, the corresponding current is the circulation current. Specifically, updating the total package charge and discharge power data of the target battery pack based on the parallel circulation current can ensure the calculation accuracy of the total package charge and discharge power data.

[0153] Step S2045, after the communication master package uploads the total package charge and discharge power data to the central control or preset charging device, the central control or preset charging device controls the charge and discharge of the target battery pack based on the total package charge and discharge power data; wherein, the communication master package is determined according to the bus position information in the current status information of each battery pack in the parallel total package.

[0154] In this embodiment, the battery pack corresponding to the lowest or highest position on the bus can be selected as the communication main pack, which is only for illustrative purposes and is not intended to be limiting.

[0155] In the embodiment of the present invention, the total package charge and discharge power data of the target battery pack are calculated respectively according to the relationship between the current charge and discharge current of the parallel total package and the first preset current threshold; and the total package charge and discharge power data is uploaded through the communication main package to enable the central control or preset charging device to control the charge and discharge of the target battery pack based on it; not only the calculation accuracy of the total package charge and discharge power data is ensured, but also the communication efficiency is improved, the control efficiency of the target battery pack is further improved, and the charging and discharging safety of the target battery pack is guaranteed.

[0156] It should be noted that when the target battery pack is in the discharge mode, it is also necessary to detect whether there is braking energy, that is, energy feedback. Therefore, the multi-pack parallel charge and discharge control method of the battery pack of this embodiment also includes:

[0157] Step F1, when it is detected that there is energy feedback in the discharge mode, the current feedback current of the parallel total package is obtained.

[0158] In this embodiment, the specific method of obtaining the current feedback current can be obtained according to conventional means in the art.

[0159] Step F2, determining whether the current feedback current is less than a second preset current threshold.

[0160] In this embodiment, the specific value of the second preset current threshold is adaptively adjusted based on actual needs.

[0161] Step F3, when the current feedback current is less than the second preset current threshold, calculate the initial total package feedback power data, and determine the initial total package feedback power data as the total package charging power state of the target battery pack, wherein the initial total package feedback power data is the maximum feedback power data in the battery pack, and the feedback power data corresponding to the battery pack is obtained by looking up the preset feedback power data table according to the current temperature and charge state of the battery pack.

[0162] In this embodiment, the specific method for obtaining the preset feedback power data table is as mentioned above and will not be repeated here.

[0163] Step F4, when the current feedback current is not less than the second preset current threshold and lasts for the second preset time, calculate the charging power status of each battery pack and the charging capacity of the battery pack, and determine the total pack feedback power data of the target battery pack based on the charging power status and charging capacity of all battery packs, wherein the charging capacity of the battery pack is obtained based on the ratio of the feedback current of the battery pack to the total charging current of all battery packs that have entered the charging mode.

[0164] In this embodiment, specific values ​​of the second preset current threshold and the second preset time are not limited here, and both can be adaptively adjusted based on actual needs.

[0165] Step F5, controlling the charging of the target battery pack based on the total pack feedback power data.

[0166] In the embodiment of the present invention, when the target battery pack is in the discharge mode, a calculation process of the total package feedback power data corresponding to the energy feedback is designed in consideration of the energy feedback situation, and the charging of the target battery pack is controlled based on the total package feedback power data, thereby achieving precise charging control of the target battery pack.

[0167] It should be noted that, considering the prerequisite for the target battery pack to forcibly exit the charge / discharge mode and re-enter the corresponding charge / discharge mode, in order to ensure the comprehensive charge / discharge control of the target battery pack, the multi-pack parallel charge / discharge control method of the battery pack of this embodiment also includes:

[0168] Step G1, if the target battery pack is forced to exit the charging mode, when the charging and discharging power data of the target battery pack is greater than the charging and discharging power data of other battery packs in the parallel pack, or after restarting the charging signal and responding to the charging signal again, the target battery pack is controlled to enter the charging mode.

[0169] Step G2: if the target battery pack is forced to exit the discharge mode, restart the discharge signal, and control the target battery pack to enter the discharge mode after responding to the discharge signal again.

[0170] In the embodiment of the present invention, when the target battery is forced to exit the charge / discharge mode, if it needs to be re-integrated into the parallel total package to enter the corresponding charge / discharge mode, the corresponding prerequisites must be met to ensure comprehensive and effective charge / discharge control of the target battery package.

[0171] In a specific embodiment, a method of parallel charging and discharging of multiple independent lithium battery packs is provided, which includes a plurality of software algorithms. The software algorithms include a multi-pack parallel charging and discharging sorting algorithm, a multi-pack parallel total pack charging / discharging SOP calculation algorithm, a multi-pack master-slave determination algorithm, a midway parallel determination algorithm, a storage position determination algorithm, etc. Specifically, the steps of parallel charging and discharging are as follows:

[0172] 1. The voltage, current, temperature, position and other information of the current battery pack are collected in real time through AFE, AD module, temperature sensor, etc.; and after the preset start signal of the battery pack is valid, the information required for parallel connection is transmitted to the communication bus to receive the parallel connection information of other battery packs in real time.

[0173] 2. Based on the received preset start signal, such as a smart charging signal or a key signal; wherein the key signal is a signal sent by the whole vehicle, and is sent to all multiple battery packs in parallel at the same time; based on the preset start signal, determine whether the battery pack is to be charged or discharged in parallel. Specifically, the current battery pack decides whether to enter the charge / discharge mode after voltage sorting, such as entering the charging mode after parallel charging sorting after establishing a communication connection with the smart charger; entering the discharge mode after parallel discharge sorting after receiving the key signal of the whole vehicle; wherein the sorting follows the sorting logic of high-voltage packs discharging first and low-voltage packs charging first, and the two packs can be charged and discharged at the same time when the difference between the two packs is not large. The parallel charge / discharge sorting of multiple packs in this embodiment can be referred to. Figure 3 and Figure 4 schematic diagram for understanding.

[0174] 3. The total package charge / discharge SOP is calculated at the same time as the preset start signal is given; if there is no charge / discharge current on the bus at the beginning (the current is obtained by adding up the currents collected by all battery packs), then the initial total package charge / discharge SOP = the maximum charge / discharge SOP of the battery pack that has entered the charge / discharge mode.

[0175] 4. During the charge / discharge period of the current battery pack, that is, when there is a charge / discharge current on the bus, the battery management system (BMS) will calculate the charge / discharge capacity of each pack in real time based on the charge / discharge current of each pack. In practical applications, since the current collection of each pack is not synchronized, the charge / discharge capacity of each pack in this embodiment = the total charge / discharge current of each pack within 3S divided by the total charge / discharge current on the bus.

[0176] 5. When there is charge / discharge current on the bus, the total charge / discharge SOP of the current battery pack = min (the charge / discharge SOP of each pack divided by its charge / discharge capacity).

[0177] 6. The charge / discharge capacity of the current battery pack is updated every 3 seconds when there is current. If there is no current, the last calculated value is maintained. If a pack is disconnected or connected in the middle, the total charge / discharge SOP of the current battery pack = the maximum charge / discharge SOP of the battery pack that has entered the charge / discharge mode. For the calculation of the charge / discharge SOP of multiple packs in parallel in this embodiment, please refer to Figure 5 and Figure 6 It needs to be explained that Figure 5 and Figure 6 In the calculation of charge / discharge capacity, Figure 6 The discharge capacity of each battery pack Z = (X × 1000) / Y and the total package SOP = single package SOP × 1000 / Z. The reason why × 1000 is required is to improve the calculation accuracy and retain three decimal places; the judgment that the total package SOP is 20% less than the maximum SOP of the single package and lasts for 2 minutes is that when a battery pack temperature is too high or too low and affects the parallel power, it will be removed to ensure the parallel efficiency, that is, to determine whether there is a high and low temperature parallel situation; the total package SOP is derived from the data of this package. The judgment process is that the total package SOP is the minimum value derived from the SOP of each package and its charge and discharge capacity, so each package has a derived total package SOP, that is, the total package SOP derived from the data of this package.

[0178] 7. When there is feedback in the discharge mode, the charging SOP only gives the maximum feedback SOP of the total package at each feedback, that is, after the feedback current is obtained, the feedback capacity of 600ms is calculated, and then the total package feedback SOP is given.

[0179] For example, when the current battery pack is in discharge mode, if the charging current is monitored, the feedback SOP needs to be calculated. Since the current has a direction, the charging current or the discharging current can be determined according to the current direction. Specifically, for the parallel battery packs a, b, and c: the feedback SOP of each pack can be obtained by looking up the table based on the current temperature and SOC; when there is no feedback current, the total pack feedback SOP is the maximum feedback SOP of the single pack; when there is feedback current and it lasts for 600ms, the total pack feedback SOP = min (the feedback SOP of each pack divided by its charging capacity).

[0180] 8. The package with the lowest position on the bus is determined as the main package, where the position can also be selected from other positions to determine the main package, which is used to communicate with the central control and upload the total package SOP. In this embodiment, only the main package has the authority to upload the calculated total package charge / discharge SOP to the bus, and as long as the controller or charger controls the charge and discharge of the battery pack according to this SOP, the actual current of multiple packages will not exceed its own capacity, and at least one package has reached its maximum capacity, so that batteries with different SOH (State of Health), different SOC (State of Charge), and different temperatures can be connected in parallel.

[0181] It should be noted that the above steps are the normal battery pack parallel charge / discharge sequence and SOP calculation process. In actual use, the following situations should also be considered, specifically:

[0182] 1. Dynamic parallel discharge: When a high-voltage package on the bus is discharging with a large current, resulting in a large voltage drop, the low-voltage package that has not yet entered the discharge mode is temporarily not allowed to enter until the original high-voltage package is lower than the total voltage of the low-voltage package to a certain value to prevent the occurrence of large circulating current. In actual applications, since the preset start signals of each battery pack are given at the same time, there will be a large voltage difference when the two voltage packs are discharged.

[0183] 2. Parallel connection during discharge: When a battery pack is already in discharge mode on the bus, the battery pack inserted in the middle is not allowed to enter the discharge mode until the discharge start signal is restarted to prevent the bus from being powered off due to reordering.

[0184] 3. High / low temperature parallel connection: When several battery packs with different temperatures are connected in parallel, resulting in the total charge / discharge SOP of the total pack being smaller than the maximum charge / discharge SOP of a single pack, the battery pack with too high or too low temperature will be kicked out of the parallel connection; if it is kicked out of the discharge mode, it can only be allowed to be connected again after the discharge start signal is restarted; if it is kicked out of the charge mode, it can only be allowed to be connected again when its charge SOP is larger than the SOP of other packs on the bus; or it can only be allowed to be connected again after the charge start signal is restarted, to prevent the parallel connection effect from being unsatisfactory.

[0185] In this embodiment, when the battery pack receives an external start signal, the battery packs on the communication bus will exchange key information such as voltage, current, charge / discharge SOP, working status, etc.; the sequencing logic of high-voltage packs discharging first and low-voltage packs charging first will independently determine whether the current battery pack enters the charging or discharging mode; during the charging and discharging process, each battery pack will calculate its own charging and discharging capacity according to the actual charging and discharging current, and then divide the current pack's charge / discharge SOP by its capacity to obtain the total pack charge / discharge SOP, and finally the main pack will send the total pack charge / discharge SOP to the controller to control the charging and discharging of the current battery pack; the cost of the control board can be saved, and no additional circuit is required. The battery packs on the bus are monitored at all times only by software algorithms. Although the circulating current cannot be eliminated, the circulating current will be controlled within a reasonable range without excessive loss; by saving the space for the control board, it can make assembly easier for car manufacturers and the entire vehicle more concise.

[0186] In summary, the parallel charging and discharging scheme of the above-mentioned battery pack can make multiple packs sorted and connected in parallel by themselves, and the total pack charging / discharging SOP is updated in real time, so as to achieve the maximum energy efficiency under the premise of ensuring that the charging / discharging current of each pack does not exceed the SOP.

[0187] In this embodiment, a multi-pack parallel charge and discharge control device for a battery pack is also provided, which is used to implement the above-mentioned embodiments and preferred implementation modes, and will not be repeated here. As the term "module" is used below, it can implement a combination of software and / or hardware with a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0188] The present invention provides a multi-pack parallel charging and discharging control device for battery packs, such as Figure 7 As shown, the device comprises:

[0189] The information acquisition module 701 is used to acquire the current status information of each battery pack in the parallel total pack, wherein the parallel total pack is composed of a target battery pack and at least one other battery pack in parallel.

[0190] The mode determination module 702 is used to respond to a preset start signal of the target battery pack and determine a charge and discharge mode of the target battery pack according to the preset start signal.

[0191] The charge and discharge sequencing module 703 is used to perform charge and discharge sequencing on the target battery pack based on the charge and discharge mode of the target battery pack and the current status information of all battery packs, and control the target battery pack to enter the charge and discharge mode.

[0192] The charge and discharge control module 704 is used to calculate the total pack charge and discharge power data of the target battery pack, and to control the charge and discharge of the target battery pack based on the total pack charge and discharge power data, wherein the total pack charge and discharge power data is determined according to the charge and discharge power data of all battery packs in the parallel total pack.

[0193] The further functional description of each of the above modules is the same as that of the above corresponding embodiments, and will not be repeated here. The multi-pack parallel charge and discharge control device of the battery pack in this embodiment is presented in the form of a functional unit, where the unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and memory that executes one or more software or fixed programs, and / or other devices that can provide the above functions.

[0194] The multi-pack parallel charge and discharge control device of the battery pack embodiment of the present invention can greatly reduce the control cost of parallel charging and discharging of multiple independent battery packs, improve the control efficiency, ensure the safe charging and discharging of parallel battery packs, and enhance the user experience.

[0195] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A method for controlling the charging and discharging of multiple battery packs in parallel, characterized in that: The method comprises: Acquire current status information of each battery pack in a parallel total pack, wherein the parallel total pack is formed by connecting a target battery pack in parallel with at least one other battery pack; In response to a preset start signal of the target battery pack, determining a charge and discharge mode of the target battery pack according to the preset start signal; Based on the charge and discharge mode of the target battery pack and current status information of all battery packs, the target battery pack is charged and discharged in a sequence, and the target battery pack is controlled to enter the charge and discharge mode; Calculate the total pack charge and discharge power data of the target battery pack, and control the charge and discharge of the target battery pack based on the total pack charge and discharge power data, wherein the total pack charge and discharge power data is determined according to the charge and discharge power data of all battery packs in the parallel total pack.

2. The method for controlling the charging and discharging of multiple battery packs in parallel according to claim 1, characterized in that: The preset start signal includes a charging signal and a discharging signal, wherein the charging signal is generated after the battery pack establishes a communication connection with a preset charging device, and the discharging signal is generated after the battery pack establishes a connection with a preset discharging device; determining the charging and discharging mode of the target battery pack according to the preset start signal includes: If the preset start signal is a charging signal, determining that the charge and discharge mode of the target battery pack is a charging mode; If the preset start signal is a discharge signal, the charge and discharge mode of the target battery pack is determined to be a discharge mode.

3. The method for controlling the charging and discharging of multiple battery packs in parallel according to claim 1, characterized in that: If the charge and discharge mode is a charging mode, the target battery pack is charged and discharged in a sequence based on the charge and discharge mode of the target battery pack and current state information of all battery packs, and the target battery pack is controlled to enter the charge and discharge mode, including: In a first preset cycle, based on current state information of all battery packs, all battery packs to be charged whose charge and discharge modes are charging modes are obtained from the parallel total pack to obtain a first charging set; The first charging set is filtered based on a preset charging condition to obtain a second charging set, wherein the preset charging condition is a charging restriction condition of the battery pack, and the charging restriction condition at least includes a situation where the battery pack is forced to exit a charging mode, a battery pack position is invalid, a battery pack communication is abnormal, and the battery pack is in a charging protection state; Determine a minimum voltage according to current state information of each battery pack to be charged in the second charging set, and calculate a first voltage difference between a current voltage corresponding to the target battery pack and the minimum voltage; If the first voltage difference is 0, it is determined that the target battery pack belongs to the low-voltage pack parallel situation, and the target battery pack is controlled to enter the charging mode after delay filtering processing; wherein, the low-voltage pack parallel situation means that when the target battery pack is incorporated into the parallel total pack, the current voltage corresponding to the target battery pack is the minimum voltage on the parallel total pack; If the first voltage difference is not 0, it is determined that the target battery pack does not belong to the low-voltage pack parallel situation, and it is judged whether the first voltage difference is greater than the first preset voltage difference threshold; if the first voltage difference is not greater than the first preset voltage difference threshold, the target battery pack is controlled to enter the charging mode after delay filtering; if the first voltage difference is greater than the first preset voltage difference threshold, the step of returning to the preset start signal in response to the target battery pack and determining the charge and discharge mode of the target battery pack according to the preset start signal is performed.

4. The method for controlling the charging and discharging of multiple battery packs in parallel according to claim 1, characterized in that: If the charge and discharge mode is a discharge mode, the target battery pack is charged and discharged in a sequence based on the charge and discharge mode of the target battery pack and current state information of all battery packs, and the target battery pack is controlled to enter the charge and discharge mode, including: In a second preset cycle, based on current state information of all battery packs, all battery packs to be discharged whose charge and discharge modes are discharge modes are obtained from the parallel total pack to obtain a first discharge set; The first discharge set is filtered based on a preset discharge condition to obtain a second discharge set, wherein the preset discharge condition is a discharge restriction condition of the battery pack, and the discharge restriction condition at least includes a situation where the battery pack is in parallel midway, a situation where the battery pack has a fault exit, a situation where the battery pack has a forced exit from a discharge mode, an invalid battery pack position, an abnormal battery pack communication, and a battery pack in a discharge protection state; Determine a maximum voltage according to current state information of each battery pack to be discharged in the second discharge set, and calculate a second voltage difference between a current voltage corresponding to the target battery pack and the maximum voltage; Determine whether the target battery pack belongs to a large current dynamic parallel connection situation, wherein the large current dynamic parallel connection situation means that when the target battery pack is incorporated into the parallel total pack, the current current corresponding to the parallel total pack is greater than a preset threshold current; When the target battery pack does not belong to the large current dynamic parallel connection situation, determine whether the second voltage difference is greater than a second preset voltage difference threshold; if the second voltage difference is not greater than the second preset voltage difference threshold, control the target battery pack to enter the discharge mode after delay filtering processing on the target battery pack; if the second voltage difference is greater than the second preset voltage difference threshold, return to the step of responding to the preset start signal of the target battery pack and determining the charge and discharge mode of the target battery pack according to the preset start signal; When the target battery pack belongs to the large current dynamic parallel situation, at least one second battery pack that is discharging in the parallel total pack is obtained, and the third voltage difference between the target battery pack and each second battery pack is calculated respectively, and each third voltage difference is judged whether it is greater than the second preset voltage difference threshold, wherein the current current of the second battery pack on the parallel total pack is greater than the preset threshold current; if all third voltage differences are greater than the second preset voltage difference threshold, the target battery pack is controlled to enter the discharge mode after delay filtering processing; if there is at least one third voltage difference that is not greater than the second preset voltage difference threshold, the step of responding to the preset start signal of the target battery pack and determining the charge and discharge mode of the target battery pack according to the preset start signal is returned.

5. The method for controlling parallel charging and discharging of multiple battery packs according to any one of claims 3 to 4, characterized in that: The calculating the total charge and discharge power data of the target battery pack includes: Detecting the current charge and discharge current of the parallel total package, wherein the current charge and discharge current is the sum of the charge and discharge currents of all battery packs in the parallel total package; Determining whether the current charge and discharge current is less than a first preset current threshold; When the current charge and discharge current is less than a first preset current threshold, initial total package charge and discharge power data is calculated, and the initial total package charge and discharge power data is determined as the total package charge and discharge power data of the target battery pack, wherein the initial total package charge and discharge power data is the maximum charge and discharge power data of the battery pack that has entered the charge and discharge mode, and the charge and discharge power data corresponding to the battery pack that has entered the charge and discharge mode is obtained by looking up a preset charge and discharge power data table according to the current temperature and charge state of the battery pack; When the current charge and discharge current is not less than a first preset current threshold, the charge and discharge power data of the battery pack that has entered the charge and discharge mode and the charge and discharge capacity of the battery pack are calculated, and the total pack charge and discharge power data of the target battery pack is determined based on the charge and discharge power data of all battery packs and the corresponding charge and discharge capacities, wherein the charge and discharge capacity of the battery pack is obtained based on the ratio of the charge and discharge current of the battery pack to the total charge and discharge current of all battery packs that have entered the charge and discharge mode.

6. The method for controlling parallel charging and discharging of multiple battery packs according to claim 5, characterized in that: The determining the total pack charge and discharge power data of the target battery pack based on the charge and discharge power data of all battery packs and the corresponding charge and discharge capabilities includes: For all battery packs including the target battery pack, respectively calculating a ratio of each battery pack, wherein the ratio is a value obtained by comparing the charge and discharge power data of a single battery pack with its corresponding charge and discharge capacity; The smallest ratio is selected from multiple ratios to obtain the total charge and discharge power data of the target battery pack.

7. The method for controlling the charging and discharging of multiple battery packs in parallel according to claim 6, characterized in that: After obtaining the total pack charge and discharge power data of the target battery pack, the method further includes: Filter the single-pack charge and discharge power data with the largest value from the charge and discharge power data of multiple battery packs; When the total pack charge-discharge power data is less than a preset ratio of the single pack charge-discharge power data and lasts for a first preset time, if the total pack charge-discharge power data is equal to the ratio of the target battery pack, controlling the target battery pack to forcibly exit the charge-discharge mode; If the total pack charge and discharge power data is not less than a preset ratio of the single pack charge and discharge power data or does not last for a preset time, or the total pack charge and discharge power data is not equal to the ratio of the target battery pack, the target battery pack continues to be charged and discharged based on the total pack charge and discharge power data.

8. The method for controlling the charging and discharging of multiple battery packs in parallel according to claim 5, characterized in that: The method further comprises: In each update cycle of the charge and discharge capability of the target battery pack, statistics are collected on the current situation of each battery pack entering or exiting the charge and discharge mode; If any battery pack enters the charge and discharge mode, the total pack charge and discharge power data currently calculated for the target battery pack is maintained, and the step of detecting the current charge and discharge current of the parallel total pack is returned to until the new total pack charge and discharge power data of the target battery pack is calculated; If any battery pack exits the charge and discharge mode, the step of detecting the current charge and discharge current of the parallel total pack is returned, and before the new total pack charge and discharge power data of the target battery pack is calculated, the maximum value in the corresponding charge and discharge power data of each battery pack in the parallel total pack is determined as the current total pack charge and discharge power data of the target battery pack.

9. The method for controlling the charging and discharging of multiple battery packs in parallel according to claim 6, characterized in that: If the charge and discharge mode is a charging mode, then after obtaining the total pack charge and discharge power data of the target battery pack, the method further includes: Obtain the parallel circulation current of the parallel package; The total pack charge and discharge power data of the target battery pack is updated based on the parallel circulation current to obtain updated total pack charge and discharge power data.

10. The method for controlling the charging and discharging of multiple battery packs in parallel according to claim 2, characterized in that: The controlling the charge and discharge of the target battery pack based on the total pack charge and discharge power data includes: After the communication master package uploads the total package charge and discharge power data to the central control or preset charging device, the central control or preset charging device controls the charge and discharge of the target battery pack based on the total package charge and discharge power data; wherein the communication master package is determined based on the bus position information in the current status information of each battery pack in the parallel total package.

11. The method for controlling the charging and discharging of multiple battery packs in parallel according to claim 1, characterized in that: If the charging and discharging mode is a discharging mode, the method further includes: When energy feedback is detected in the discharge mode, the current feedback current of the parallel package is obtained; Determining whether the current feedback current is less than a second preset current threshold; When the current feedback current is less than the second preset current threshold, the initial total package feedback power data is calculated, and the initial total package feedback power data is determined as the total package charging power state of the target battery pack, wherein the initial total package feedback power data is the maximum feedback power data in the battery pack, and the feedback power data corresponding to the battery pack is obtained by looking up the preset feedback power data table according to the current temperature and charge state of the battery pack; When the current feedback current is not less than a second preset current threshold and lasts for a second preset time, the charging power state of each battery pack and the charging capacity of the battery pack are calculated, and the total pack feedback power data of the target battery pack is determined based on the charging power states and the charging capacities of all battery packs, wherein the charging capacity of the battery pack is obtained according to the ratio of the feedback current of the battery pack to the total charging current of all battery packs that have entered the charging mode; The target battery pack is charged and controlled based on the total pack feedback power data.

12. The method for controlling charge and discharge of multiple battery packs in parallel according to claim 6, characterized in that: The method further comprises: If the target battery pack is forced to exit the charging mode, when the charging and discharging power data of the target battery pack is greater than the charging and discharging power data of other battery packs in the parallel total pack, or after restarting the charging signal and responding to the charging signal again, control the target battery pack to enter the charging mode; If the target battery pack is forced to exit the discharge mode, the discharge signal is restarted, and the target battery pack is controlled to enter the discharge mode after responding to the discharge signal again.

13. A battery pack parallel charging and discharging control device, characterized in that: The device comprises: An information acquisition module, used to acquire current status information of each battery pack in a parallel total pack, wherein the parallel total pack is composed of a target battery pack and at least one other battery pack in parallel; a mode determination module, configured to respond to a preset start signal of the target battery pack and determine a charge and discharge mode of the target battery pack according to the preset start signal; A charge and discharge sequencing module, configured to perform charge and discharge sequencing on the target battery pack based on the charge and discharge mode of the target battery pack and current status information of all battery packs, and control the target battery pack to enter the charge and discharge mode; A charge and discharge control module is used to calculate the total pack charge and discharge power data of the target battery pack, and to control the charge and discharge of the target battery pack based on the total pack charge and discharge power data, wherein the total pack charge and discharge power data is determined according to the charge and discharge power data of all battery packs in the parallel total pack.

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