Method, device and control system for assembling battery pack

Abstract

The embodiment of the invention provides a method and device for assembling a battery pack and a control system. The method comprises the following steps: determining whether the direct-current resistance of n battery units meets a first condition, wherein n is a positive integer greater than 1; and under the condition that the direct-current resistance of the n battery units meets a first condition, assembling the n battery units into a battery pack. According to the method, the device and the control system provided by the embodiment of the invention, the consistency of the direct-current resistance of the battery pack can be improved, the occurrence probability of a non-uniform current phenomenon in a charging process or a discharging process is reduced, and the service life of a product is prolonged.

Description

Technical Field

[0001] The present application relates to the technical field of batteries, and particularly to a method, device, and control system for assembling a battery pack. Background Art

[0002] Due to the requirements of high voltage and large capacity in existing energy storage systems, a large number of batteries need to be connected in series and parallel to assemble into a container and then exchange energy with the power grid through an energy storage converter. During the process of assembling the container, due to the poor consistency of the direct current resistance (DCR) between the parallel battery packs, uneven current distribution occurs between the container clusters, which affects the power output of the entire system's containers and reduces the overall lifespan. Summary of the Invention

[0003] Embodiments of the present application provide a method, device, and control system for assembling a battery pack, which are beneficial to improving the consistency of the direct current resistance of the battery pack, reducing the probability of uneven current distribution at the end of charging or discharging, and increasing the lifespan of the product.

[0004] In a first aspect, a method for assembling a battery pack is provided. The method includes: determining whether the direct current resistances of n battery cells meet a first condition, where n is a positive integer greater than 1; and assembling the n battery cells into a battery pack when the direct current resistances of the n battery cells meet the first condition.

[0005] In this embodiment, by determining whether the direct current resistances of n battery cells meet the first condition and assembling the n battery cells into a battery pack when the direct current resistances of the n battery cells meet the first condition, that is, when assembling the battery pack, controlling the direct current resistance of the battery cells is beneficial to improving the consistency of the direct current resistance of the battery pack, reducing the probability of uneven current distribution at the end of charging or discharging, and increasing the lifespan of the product.

[0006] In a possible implementation, the method further includes: obtaining the first direct current resistance value of each of the n battery cells; where determining whether the direct current resistances of the n battery cells meet the first condition includes: determining whether the sum of the first direct current resistance values of the n battery cells is within a first preset range.

[0007] In this embodiment, when assembling the battery pack, a control range for the direct current resistance of the battery pack is given, and the n battery cells are assembled into a battery pack only when it is monitored that the sum of the first direct current resistance values of the n battery cells is within the control range of the direct current resistance. This method has simple control steps and convenient operation, and is also beneficial to improving the consistency of the direct current resistance between battery packs, reducing the probability of uneven current distribution at the end of charging or discharging, and increasing the lifespan of the product.

[0008] In a possible implementation, n battery cells enter the assembly line continuously.

[0009] In a possible implementation, at least two adjacent battery cells among the n battery cells do not enter the assembly line continuously.

[0010] In a possible implementation, determining whether the sum of the first DC resistance values of the n battery cells is within a first preset range includes: when the sum of the first DC resistance values of m battery cells that enter the assembly line continuously is not within the first preset range, determining whether the sum of the first DC resistance values of the n battery cells is within the first preset range; where the n battery cells include (m - i) battery cells among the m battery cells and the first i battery cells that enter the assembly line after the m battery cells, m = n, and i is a positive integer less than m.

[0011] In this embodiment, when the sum of the first DC resistance values of m battery cells that enter the assembly line continuously is not within the DC resistance control range, it is further possible to determine whether the sum of the first DC resistance values of (m - i) battery cells among the m battery cells and the first i battery cells produced after the m battery cells is within the DC resistance control range, so that the control system can quickly calculate the sum of the first DC resistance values of the n battery cells without waiting, improving the assembly efficiency of the battery pack.

[0012] In a possible implementation, the method further includes: controlling i battery cells among the m battery cells, except for the (m - i) battery cells, to enter the assembly line through the abnormal battery cell channel in a loop.

[0013] In this embodiment, by controlling i battery cells among the m battery cells, except for the (m - i) battery cells, to enter the assembly line through the abnormal battery cell channel in a loop, it is beneficial to improve the DC resistance consistency among the formed battery packs while making all the battery cells on the assembly line be assembled into battery packs as much as possible, improving the production capacity of the system.

[0014] In a possible implementation, i battery cells among the m battery cells are closer to the abnormal battery cell channel than the (m - i) battery cells.

[0015] In this embodiment, when the control system monitors that the first DC resistance values of n battery cells do not meet the DC resistance control range, the channels of the n battery cells close to the abnormal battery cell channel quickly enter the abnormal battery cell channel, so that once the control system monitors again that the first DC resistance values of the n battery cells meet the DC resistance control range, the n battery cells that meet the DC resistance control range can be directly assembled into a battery pack without waiting for the abnormal battery cell to enter the abnormal battery cell channel before assembly, thereby improving the assembly efficiency of the battery pack.

[0016] In a possible implementation, i = 1.

[0017] In this embodiment, once it is monitored that the sum of the first DC resistance values of m battery cells does not meet the DC resistance control range, only one of the m battery cells needs to be replaced, which is beneficial to quickly matching n battery cells that meet the DC resistance control range, thereby improving the assembly efficiency of the battery pack.

[0018] In a possible implementation, the method further includes: obtaining the first DC resistance value of each of the n battery cells; wherein, determining whether the DC resistance of the n battery cells meets the first condition includes: determining whether the first DC resistance value of each of the n battery cells is within a second preset range.

[0019] In this embodiment, each battery cell is graded according to the first DC resistance value of each battery cell, and finally the n battery cells belonging to the same grade are assembled into a battery pack. This method has simple control steps and convenient operation, and can also improve the consistency of the DC resistance between the battery cells in the battery pack.

[0020] In a possible implementation, obtaining the first DC resistance value of each of the n battery cells includes: obtaining the second DC resistance value of each of the n battery cells; performing temperature correction and / or time correction on the second DC resistance value of each battery cell to obtain the first DC resistance value of each battery cell.

[0021] In this embodiment, time correction and / or temperature correction are performed on the obtained second DC resistance value of the battery cell to obtain the first DC resistance value of the battery cell. Furthermore, the first DC resistance value of the battery cell can be used as a basis for judging whether a battery pack can be assembled, making the control of the DC resistance of the battery pack more accurate and improving the consistency of the DC resistance between the battery cells in the battery pack.

[0022] In a possible implementation, obtaining the second DC resistance value of each battery cell among n battery cells includes: performing a DC resistance test on each battery cell at a test temperature to obtain the second DC resistance value of each battery cell; performing temperature correction on the second DC resistance value of each battery cell to obtain the first DC resistance value of each battery cell, including: correcting the second DC resistance value obtained at the test temperature to the first DC resistance value at a reference temperature.

[0023] In this embodiment, correcting the second DC resistance value at the test temperature to the first DC resistance value at the reference temperature can make the first DC resistance values of multiple battery cells all correspond to the same temperature, eliminating the influence of temperature on the difference in the first DC resistance values between battery cells, so that a more accurate DC resistance value can be obtained, providing a reliable basis for the consistency judgment of the DC resistance.

[0024] In a possible implementation, correcting the second DC resistance value obtained at the test temperature to the first DC resistance value at the reference temperature includes: correcting the second DC resistance value to the first DC resistance value according to the ratio between the first function value and the second function value, where the first function value and the second function value are values obtained by substituting the reference temperature and the test temperature into the first mapping function of the DC resistance value and the temperature.

[0025] In a possible implementation, correcting the second DC resistance value of each battery cell according to the ratio between the second DC resistance value and the first DC resistance value of a reference battery cell to obtain the first DC resistance value of each battery cell, where the first DC resistance value of the reference battery cell is obtained by substituting the storage time of the reference battery cell and the second DC resistance value of the reference battery cell into the second mapping function of the DC resistance value and the storage time.

[0026] In a possible implementation, performing time correction on the second DC resistance value of each battery cell to obtain the first DC resistance value of each battery cell includes: substituting the storage time of each battery cell and the second DC resistance of each battery cell into the third mapping function of the DC resistance value and the storage time to obtain the first DC resistance value of each battery cell.

[0027] In a possible implementation, the battery pack is an electrical box and the battery cell is a battery monomer; or, the battery pack is an electrical cabinet and the battery cell is an electrical box.

[0028] In a second aspect, a device for assembling a battery pack is provided. The device includes: a determination unit configured to determine whether the direct current resistances of n battery cells satisfy a first condition, where n is a positive integer greater than 1; and an assembly unit configured to assemble the n battery cells into a battery pack when the direct current resistances of the n battery cells satisfy the first condition.

[0029] In a possible implementation, the device further includes: an acquisition unit configured to acquire a first direct current resistance value of each of the n battery cells; wherein the determination unit is specifically configured to determine whether the sum of the first direct current resistance values of the n battery cells is within a first preset range.

[0030] In a possible implementation, the n battery cells enter the assembly production line continuously.

[0031] In a possible implementation, at least two adjacent battery cells among the n battery cells do not enter the assembly production line continuously.

[0032] In a possible implementation, the determination unit is specifically configured to: when the sum of the first direct current resistance values of m battery cells that enter the assembly production line continuously is not within the first preset range, determine whether the sum of the first direct current resistance values of the n battery cells is within the first preset range, where the n battery cells include (m - i) battery cells among the m battery cells and the first i battery cells that enter the assembly production line after the m battery cells, m = n, and i is a positive integer less than m.

[0033] In a possible implementation, the device further includes: a control unit configured to control the i battery cells other than the (m - i) battery cells among the m battery cells to enter the assembly production line through the abnormal battery cell channel in a loop.

[0034] In a possible implementation, the i battery cells among the m battery cells are closer to the abnormal battery cell channel than the (m - i) battery cells.

[0035] In a possible implementation, i = 1.

[0036] In a possible implementation, the device further includes: an acquisition unit configured to acquire a first direct current resistance value of each of the n battery cells; wherein the determination unit is specifically configured to determine whether the first direct current resistance value of each of the n battery cells is within a second preset range.

[0037] In a possible implementation, the acquisition unit is specifically configured to: acquire a second direct current resistance value of each of the n battery cells; perform temperature correction and / or time correction on the second direct current resistance value of each battery cell to obtain the first direct current resistance value of each battery cell.

[0038] In a possible implementation, the obtaining unit is specifically configured to: perform a direct current resistance test on each battery cell at a test temperature to obtain a second direct current resistance value of each battery cell; and correct the second direct current resistance value obtained at the test temperature to a first direct current resistance value at a reference temperature.

[0039] In a possible implementation, the obtaining unit is specifically configured to: correct the second direct current resistance value to the first direct current resistance value according to the ratio between a first function value and a second function value, where the first function value and the second function value are values obtained by substituting the reference temperature and the test temperature into a first mapping function of the direct current resistance value and the temperature, respectively.

[0040] In a possible implementation, the obtaining unit is specifically configured to: correct the second direct current resistance value of each battery cell according to the ratio between the second direct current resistance value and the first direct current resistance value of a reference battery cell, to obtain the first direct current resistance value of each battery cell, where the first direct current resistance value of the reference battery cell is obtained by substituting the storage time of the reference battery cell and the second direct current resistance value of the reference battery cell into a second mapping function of the direct current resistance value and the storage time.

[0041] In a possible implementation, the obtaining unit is specifically configured to: substitute the storage time of each battery cell and the second direct current resistance of each battery cell into a third mapping function of the direct current resistance value and the storage time, to obtain the first direct current resistance value of each battery cell.

[0042] In a possible implementation, the battery pack is an electrical box and the battery cell is a battery monomer; or, the battery pack is an electrical cabinet and the battery cell is an electrical box.

[0043] In a third aspect, a control system for assembling a battery pack is provided, including a memory and a processor, where the memory is used to store instructions, and the processor is used to read the instructions and execute the method in the first aspect and any possible implementation manner of the first aspect according to the instructions.

[0044] In a fourth aspect, a chip is provided, including a processor, configured to call and run a computer program from a memory, so that a device installed with the chip executes the method in the first aspect and any possible implementation manner of the first aspect.

[0045] In a fifth aspect, a computer program is provided, which enables a computer to execute the method in the first aspect and any possible implementation manner of the first aspect.

[0046] In a sixth aspect, a computer-readable storage medium is provided for storing a computer program, which causes a computer to execute the method in the first aspect and any possible implementation manner of the first aspect.

[0047] In a seventh aspect, a computer program product is provided, including computer program instructions, which cause a computer to execute the method in the first aspect and any possible implementation manner of the first aspect. Description of the Drawings

[0048] To more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on the drawings without creative efforts.

[0049] Figure 1 Shows the assembly process diagram of the container in the embodiment of the present application.

[0050] Figure 2 Shows a schematic block diagram of the first method for assembling a battery pack in the embodiment of the present application.

[0051] Figure 3 Shows a schematic block diagram of the second method for assembling a battery pack in the embodiment of the present application.

[0052] Figure 4 Shows an assembly diagram of an electrical box in the embodiment of the present application.

[0053] Figure 5 Shows another assembly diagram of an electrical box in the embodiment of the present application.

[0054] Figure 6 Shows a schematic block diagram of the third method for assembling a battery pack in the embodiment of the present application.

[0055] Figure 7 Shows a production process diagram of assembling an electrical cabinet in the embodiment of the present application.

[0056] Figure 8 Shows a schematic block diagram of the fourth method for assembling a battery pack in the embodiment of the present application.

[0057] Figure 9 Shows a schematic block diagram of the fifth method for assembling a battery pack in the embodiment of the present application.

[0058] Figure 10 Shows a schematic curve diagram between the DCR value and the storage time of the battery cell in the embodiment of the present application.

[0059] Figure 11Shows a schematic block diagram of the sixth method for assembling a battery pack according to an embodiment of the present application.

[0060] Figure 12 Shows a schematic block diagram of the seventh method for assembling a battery pack according to an embodiment of the present application.

[0061] Figure 13 Shows a schematic block diagram of the eighth method for assembling a battery pack according to an embodiment of the present application.

[0062] Figure 14 Shows a schematic flowchart of a method for assembling an electrical cabinet according to an embodiment of the present application.

[0063] Figure 15 Shows a schematic flowchart of a method for assembling an electrical box according to an embodiment of the present application.

[0064] Figure 16 Shows a schematic block diagram of a device for assembling a battery pack according to an embodiment of the present application.

[0065] Figure 17 Shows another schematic block diagram of a device for assembling a battery pack according to an embodiment of the present application.

[0066] Figure 18 Shows a schematic block diagram of a control system for assembling a battery pack according to an embodiment of the present application. Detailed Embodiments

[0067] The following further describes the embodiments of the present application in detail in conjunction with the accompanying drawings and examples. The detailed descriptions and drawings of the following examples are used to exemplarily illustrate the principles of the present application, but cannot be used to limit the scope of the present application, that is, the present application is not limited to the described embodiments.

[0068] In the description of the present application, it should be noted that unless otherwise specified, the meaning of "a plurality" is more than two; the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "inner", "outer", etc. is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application. In addition, terms such as "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. "Vertical" is not strictly vertical, but within the allowable error range. "Parallel" is not strictly parallel, but within the allowable error range.

[0069] The orientation terms used in the following description are all the directions shown in the figures, and do not limit the specific structure of the present application. In the description of the present application, it should also be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0070] The term "and / or" in the present application is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: there is A, there is both A and B, and there is B. In addition, the character " / " in the present application generally represents an "or" relationship between the preceding and following associated objects.

[0071] Unless otherwise defined, all technical and scientific terms used in the present application have the same meaning as commonly understood by those skilled in the technical field to which the present application belongs; the terms used in the specification of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application; the terms "including" and "having" and any variations thereof in the specification and claims of the present application and the above drawings are intended to cover non-exclusive inclusion. The terms "first", "second", etc. in the specification and claims of the present application or the above drawings are used to distinguish different objects, and are not used to describe a specific order or primary-secondary relationship.

[0072] Referring to "embodiment" in the present application means that the specific features, structures, or characteristics described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of this phrase in various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described in the present application can be combined with other embodiments.

[0073] A battery refers to a single physical module including one or more battery cells to provide higher voltage and capacity. For example, a battery can be a battery system. The battery system in the present application refers to a battery assembly in which battery units are connected in series, parallel, or a combination of series and parallel, where a combination of series and parallel means a mixture of series and parallel. For example, the battery pack in the present application can be an electrical box, and the battery unit is a battery cell, that is, the electrical box can be formed by connecting multiple battery cells in series and / or in parallel. Another example is that the battery pack in the present application can be an electrical cabinet, also referred to as a battery cluster, and the battery unit is an electrical box, that is, the electrical cabinet is formed by connecting multiple electrical boxes in series and / or in parallel.

[0074] Optionally, the battery in the embodiments of the present application may be a lithium-ion battery, a lithium metal battery, a lead-acid battery, a nickel-cadmium battery, a nickel-metal hydride battery, a lithium-sulfur battery, a lithium-air battery, or a sodium-ion battery, etc., and the embodiments of the present application do not make specific limitations thereon.

[0075] Currently, due to the requirements of high voltage and large capacity for energy storage systems, a large number of batteries need to be connected in series and parallel to assemble into a container product and then exchange energy with the power grid through a PCS. During the process of assembling into a container, due to the problem of DCR consistency between parallel battery clusters, the charge and discharge power of the container decreases and the overall life decreases.

[0076] In view of this, the embodiments of the present application provide a method for assembling a battery pack. By determining whether the DCR of n battery cells meets the first condition, and when the DCR of the n battery cells meets the first condition, assembling the n battery cells into a battery pack, that is, controlling the DCR of the battery cells during the assembly of the battery pack, which is beneficial to improving the consistency of the DCR of the battery pack, reducing the probability of uneven current flow during the charging process or the discharging process, and improving the life of the product.

[0077] Figure 1 The figure shows the assembly process diagram of the container. As Figure 1 shown, the battery cell is the smallest unit. An electrical box is assembled by L battery cells, where L is a positive integer greater than 1. An electrical cabinet is assembled by P electrical boxes, where P is a positive integer greater than 1. A container is formed by parallel connection of Q electrical cabinets, where Q is a positive integer greater than 1.

[0078] It should be understood that the battery pack in the embodiments of the present application may be an electrical box, an electrical cabinet, or even a container.

[0079] It should also be understood that the technical solutions in the embodiments of the present application can be applied not only to energy storage batteries but also to power batteries.

[0080] Figure 2 The figure shows a schematic block diagram of a method 100 for assembling a battery pack according to an embodiment of the present application. Optionally, the method 100 may be executed by a control system in the battery automated production and assembly process. For example, the method 100 may be executed by a Manufacturing Execution System (MES), and the method 100 may include the following parts or all of the content.

[0081] S110, determine whether the direct current resistance of n battery cells meets the first condition, where n is a positive integer greater than 1.

[0082] S120, when the direct current resistance of the n battery cells meets the first condition, assemble the n battery cells into a battery pack.

[0083] First, DCR refers to the resistance that the current encounters when flowing through the inside of the battery during operation, including ohmic internal resistance and polarization internal resistance. The ohmic internal resistance is mainly determined by the total conductivity of the battery, while the polarization internal resistance is mainly determined by the solid-phase diffusion coefficient of lithium ions in the electrode active material. Generally, DCR can be calculated by applying a relatively large current to the battery for a short period of time, and based on the voltage change of the battery before and after the applied current and the applied current, the DCR value of the battery can be calculated.

[0084] In some embodiments, to determine whether the DCR of n battery cells satisfies the first condition, it can be to regard the n battery cells as a whole, that is, perform a certain arithmetic operation on the DCR values of each battery cell in the n battery cells to obtain a DCR value, and then further determine whether the DCR value satisfies a certain condition. The situation where the DCR value obtained after performing a certain arithmetic operation on the DCR values of each battery cell in the n battery cells satisfies a certain condition is regarded as the DCR of the n battery cells satisfying the first condition. For example, determine whether the DCR value is within a certain preset range.

[0085] In other embodiments, to determine whether the DCR of n battery cells satisfies the first condition, it can also be that each battery cell in the n battery cells has a DCR value, and respectively determine whether the DCR value of each battery cell satisfies a certain condition. The situation where the DCR values of the n battery cells respectively satisfy a certain condition is determined as the DCR of the n battery cells satisfying the first condition. For example, it can be determined whether the DCR value of each battery cell in the n battery cells is within a certain preset range.

[0086] In other embodiments, on the premise that the situation where the DCR values of n battery cells respectively satisfy a certain condition is determined as the DCR of the n battery cells satisfying the first condition, the determination conditions for the DCR values of each battery cell can be different. For example, the situation where the DCR value of each battery cell in a part of the n battery cells is within the first DCR interval and the DCR value of each battery cell in another part of the n battery cells is within the second DCR interval is regarded as the DCR of the n battery cells satisfying the first condition.

[0087] Assembling n battery cells into a battery pack means electrically connecting the n battery cells in series and / or in parallel through connecting components. Further, the n battery cells electrically connected together can be housed in a housing to form a battery pack. For example, n battery monomers are housed in a box to form an electrical box. For another example, n electrical boxes are housed in a cabinet to form an electrical cabinet. The connecting components may include at least one of a busbar component, a fuse, a high-voltage harness, and a switch. For example, if the battery pack is an electrical box, the electrical box can be formed by connecting multiple battery monomers through a busbar component so that electrical energy can be transmitted between the multiple battery monomers. The electrical box also includes a fuse and a manual maintenance switch for protecting the circuit and preventing abnormal conditions such as overcurrent or overheating from damaging the electrical box. For another example, if the battery pack is an electrical cabinet, the electrical cabinet can be composed of multiple electrical boxes connected through a high-voltage harness and various functional connecting components in the main control box. For example, the functional connecting components may include a busbar component, a fuse, a disconnector, a circuit breaker, a current sensor, and a connector, etc.

[0088] In this embodiment, by determining whether the DCR of n battery cells meets a first condition, and when the DCR of the n battery cells meets the first condition, assembling the n battery cells into a battery pack, that is, controlling the DCR of the battery cells during the assembly of the battery pack, is beneficial to improving the consistency of the DCR of the battery pack, reducing the occurrence probability of uneven current distribution during the charging process or the discharging process, and improving the product life.

[0089] In one embodiment, as Figure 3 shown, the method 100 further includes: S105, obtaining the first DC resistance value of each of the n battery cells; where S110, that is, determining whether the DC resistance of the n battery cells meets the first condition, includes: S111, determining whether the sum of the first DC resistance values of the n battery cells is within a first preset range. Further, S120, that is, when the DC resistance of the n battery cells meets the first condition, assembling the n battery cells into a battery pack, specifically includes: when the sum of the first DC resistance values of the n battery cells is within the first preset range, assembling the n battery cells into a battery pack.

[0090] For example, the battery pack is an electrical box and the battery cells are battery monomers. Obtain the first DCR value of each of the n battery monomers respectively, and calculate the cumulative sum of the first DCR values of the n battery monomers, and then determine whether the cumulative sum of the first DCR values of the n battery monomers is within the first preset range.

[0091] In the case where the battery pack is an electrical box, the battery cells can be just single battery monomers, and then the n battery monomers are connected in series. For example, as Figure 4As shown, the electric box is formed by connecting n battery cells in series. Assuming that the first DCR value of battery cell 1 is DCR1, the first DCR value of battery cell 2 is DCR2, and so on, the first DCR value of battery cell n is DCR n , the cumulative sum x of the first DCR values of n battery cells can be calculated by the following formula:

[0092] x=DCR1+DCR2+……+DCR n (1).

[0093] In the case where the battery pack is an electrical box, the battery unit can also be a battery cell group, where a battery cell group includes at least two battery cells connected in parallel, and then n battery cell groups are connected in series. Figure 5 As shown, the electric box is formed by n battery cell groups connected in series, and each battery cell group is formed by 2 battery cells connected in parallel. Assume that the first DCR value of battery cell 1 is DCR1, the first DCR value of battery cell 2 is DCR2, ..., and so on. The first DCR value of battery cell 2n-1 is DCR 2n-1 The first DCR value of battery cell 2n is DCR 2n Then the cumulative sum x of the first DCR values of n battery cells can be calculated by the following formula:

[0094]

[0095] For another example, if the battery pack is a cabinet, the battery cells are electrical boxes, and n electrical boxes are connected in series, the cumulative sum x of the first DCR values of the n electrical boxes can also be calculated using the above formula (1).

[0096] It should be noted that the first DCR value of each battery cell can be obtained through testing or calculated by other means. For example, for battery cells assembled into an electrical box, the first DCR value of each battery cell can be obtained through testing. For another example, for electrical boxes assembled into an electrical cabinet, the first DCR value of each electrical box can be obtained through testing or by calculating the cumulative sum of the first DCR values of the battery cells included in each electrical box.

[0097] In addition, the first preset range may be a DCR control range set before assembling the battery pack, for example, the DCR control range is [DCR 下限 ,DCR 上限 When assembling the battery pack, the control system can control the barcode scanning device to scan the identification of each battery cell and obtain the first DCR value of each battery cell. The control system can sequentially accumulate the first DCR values of n battery cells. If the cumulative sum x of the first DCR values of the n battery cells belongs to [DCR下限 , DCR 上限 , then the n battery cells are assembled normally, packed and sent to the warehouse.

[0098] In this embodiment, when assembling the battery pack, the DCR control range of a given battery pack is set, and the n battery cells are assembled into a battery pack only when the sum of the first DCR values of the n battery cells is within the DCR control range. This method has simple control steps and convenient operation. It is also beneficial to improve the consistency of DCR among battery packs, reduce the probability of uneven current flow during the charging or discharging process, and improve the product life.

[0099] In some embodiments, the n battery cells enter the assembly line continuously.

[0100] In other embodiments, at least two adjacent battery cells among the n battery cells do not enter the assembly line continuously.

[0101] Generally, when assembling battery cells into a battery pack, the battery cells enter the assembly line in sequence, that is, the battery cells are conveyed on the conveyor belt in sequence. In the embodiments of the present application, the control system can monitor each battery cell entering the assembly line, and first calculate the cumulative sum of the first DCR values of n consecutive battery cells. If the cumulative sum of the first DCR values of the n consecutive battery cells meets the DCR control range, the n consecutive battery cells can be directly assembled into a battery pack. If the cumulative sum of the first DCR values of the n consecutive battery cells does not meet the DCR control range, some of the n consecutive battery cells can be replaced until the cumulative sum of the first DCR values of the new n battery cells is within the DCR control range, and the new n battery cells are assembled into a battery pack. Since some of the new n battery cells are replaced by other battery cells, the new n battery cells assembled into the battery pack are not completely consecutive.

[0102] In this embodiment, by assembling n battery cells whose cumulative sum of the first DCR values meets the DCR control range into a battery pack, and by replacing battery cells for n battery cells whose cumulative sum of the first DCR values does not meet the DCR control range until the cumulative sum of the first DCR values of the replaced n battery cells is finally within the DCR control range, the consistency of DCR among battery packs can be improved, the probability of uneven current flow during the charging or discharging process can be reduced, and the product life can be improved.

[0103] In some embodiments, such as Figure 6As shown, S111, that is, determining whether the sum of the first DC resistance values of n battery cells is within a first preset range, includes: S1110, in the case where the sum of the first DC resistance values of m battery cells continuously entering the assembly line is not within the first preset range, determining whether the sum of the first DC resistance values of n battery cells is within the first preset range, where the n battery cells include (m - i) battery cells among the m battery cells and the first i battery cells that enter the assembly line after the m battery cells, m = n, and i is a positive integer less than m.

[0104] It should be noted that the m battery cells and the n battery cells in the embodiments of the present application respectively represent the same number of different battery cells, that is to say, the number of the m battery cells and the n battery cells is the same, but at least one of the battery cells in the two is a different battery cell. The m battery cells here can be understood as the m battery cells that were added and calculated in the previous round, and the n battery cells can be understood as the m battery cells that will be added and calculated in the next round.

[0105] For example, as Figure 7 shown, taking the electrical boxes forming an electrical cabinet as an example, an electrical cabinet requires 8 electrical boxes. The control system monitors the electrical boxes entering the assembly line and accumulates the sum of the first DCR values of 8 electrical boxes in real time. When the accumulated sum of the first DCR values of the first round of 8 electrical boxes (electrical box 1, electrical box 2, electrical box 3, electrical box 4, electrical box 5, electrical box 6, electrical box 7, and electrical box 8) meets the DCR control range, the first round of 8 electrical boxes will be directly assembled into an electrical cabinet and enter the electrical cabinet stacking area. When the accumulated sum of the first DCR values of the first round of 8 electrical boxes does not meet the DCR control range, the accumulated sum of the first DCR values of the second round of 8 electrical boxes can be calculated. The second round of 8 electrical boxes can include the last 7 electrical boxes among the first round of 8 electrical boxes and the first electrical box after the first round of 8 electrical boxes. For example, the second round of 8 electrical boxes includes electrical box 2, electrical box 3, electrical box 4, electrical box 5, electrical box 6, electrical box 7, electrical box 8, and electrical box 9. It should be noted that the electrical boxes 1 to 8 in the electrical cabinet stacking area are only used to illustrate the number of electrical boxes included in an electrical cabinet, rather than specifically referring to the electrical boxes 1 to 8 on the assembly line.

[0106] In this embodiment, in the case where the sum of the first DCR values of m battery cells continuously entering the assembly line is not within the DCR control range, it is further possible to determine whether the sum of the first DCR values of (m - i) battery cells among the m battery cells and the first i battery cells produced after the m battery cells is within the DCR control range, so that the control system can quickly recalculate the sum of the first DCR values of n battery cells without waiting, improving the assembly efficiency of the battery pack.

[0107] Further optionally, as Figure 6As shown, the method 100 further includes: S130, controlling i battery cells out of the m battery cells, except for (m - i) battery cells, to enter the assembly line in a cycle through the abnormal battery cell channel.

[0108] For example, as Figure 7 shown, continuing with the example of electrical boxes forming an electrical cabinet, when the sum of the first DCR values of the 8 electrical boxes in the first round (for example, electrical box 1, electrical box 2, electrical box 3, electrical box 4, electrical box 5, electrical box 6, electrical box 7, and electrical box 8) calculated by the control system does not meet the DCR control range, then while calculating the sum of the first DCR values of the 8 electrical boxes (electrical box 2, electrical box 3, electrical box 4, electrical box 5, electrical box 6, electrical box 7, electrical box 8, and electrical box 9) in the second round, the control system controls electrical box 1 among the 8 electrical boxes in the first round to enter the abnormal battery cell channel, and this abnormal battery cell channel leads directly to the assembly line. Then, electrical box 1 passing through this abnormal battery cell channel can enter the assembly line again and be re-monitored by the control system.

[0109] In this embodiment, by controlling i battery cells out of the m battery cells, except for (m - i) battery cells, to enter the assembly line in a cycle through the abnormal battery cell channel, it is beneficial to improve the DCR consistency between battery packs while making it possible for all battery cells on the assembly line to be assembled into battery packs as much as possible, thus improving the production capacity of the battery packs.

[0110] In some embodiments, the i battery cells among the m battery cells that enter the abnormal battery cell channel are closer to the abnormal battery cell channel than the (m - i) battery cells that do not enter the abnormal battery cell channel.

[0111] In this embodiment, when the control system monitors that the first DCR values of the above m battery cells do not meet the DCR control range, it controls the battery cells among the m battery cells that are close to the abnormal battery cell channel to quickly enter the abnormal battery cell channel, so that once the control system monitors again that the first DCR values of the above n battery cells meet the DCR control range, it can directly assemble the n battery cells that meet the DCR control range into a battery pack without having to wait for the abnormal battery cell to enter the abnormal battery cell channel before assembling, thereby improving the assembly efficiency of the battery pack.

[0112] In some embodiments, i = 1.

[0113] That is to say, once it is monitored that the sum of the first DCR values of the above m battery cells does not meet the DCR control range, only one battery cell among the m battery cells needs to be replaced, which is beneficial for quickly matching the above n battery cells, thereby improving the assembly efficiency of the battery pack.

[0114] In other embodiments, once it is monitored that the sum of the first DCR values of the above m battery cells does not meet the DCR control range, the last battery cell that enters the assembly line among the m battery cells is returned to the assembly line through the abnormal battery cell channel, and is replaced by the first battery cell that enters the assembly line after the m battery cells.

[0115] Although the above mainly takes the electrical boxes forming an electrical cabinet as an example for illustration, those skilled in the art understand that the control system can also execute the above various processes when assembling battery monomers into electrical boxes.

[0116] In some embodiments, as Figure 8 shown, method 100 further includes: S105, obtaining the first DC resistance value of each of the n battery cells; wherein, S110, that is, determining whether the DC resistance of the n battery cells meets the first condition, includes: S112, determining whether the first DC resistance value of each of the n battery cells is within a second preset range. Further, S120, that is, when the DC resistance of the n battery cells meets the first condition, assembling the n battery cells into a battery pack, specifically including: when the first DC resistance value of each of the n battery cells is within the second preset range, assembling the n battery cells into a battery pack.

[0117] Specifically, before assembling the battery cells into a battery pack, at least one DCR preset range for grading the battery cells can be formulated in advance. After obtaining the first DCR value of each battery cell, it can be judged one by one which grade the first DCR value of each battery cell belongs to, and then n battery cells belonging to the same grade are assembled into a battery pack.

[0118] Taking the assembly of battery cells into an electrical box as an example, three DCR preset ranges can be set, corresponding to S gear, T gear, and U gear in ascending order. After the control system obtains the first DCR value of a battery cell, it can first determine whether the battery cell belongs to the S gear. If it does, the battery cell is marked as the S gear or placed in a fixed position belonging to the S gear; if not, it continues to determine whether the battery cell belongs to the T gear. If it does, the battery cell is marked as the T gear or placed in a fixed position belonging to the T gear; if not, it continues to determine whether the battery cell belongs to the U gear. If it does, the battery cell is marked as the U gear or placed in a fixed position belonging to the U gear; if not, the battery cell is placed in the scrap area. Each battery cell can be classified according to such a process. Whenever the number of battery cells belonging to the same gear can be assembled into an electrical box, multiple battery cells of the same gear are directly assembled into an electrical box, and the electrical box can also be marked with the same gear as the battery cell, so that subsequent electrical boxes belonging to the same gear can be assembled into an electrical cabinet. Similarly, the electrical cabinet can also be marked with the same gear as the electrical box, so that subsequent electrical cabinets belonging to the same gear can be assembled into a container. In this way, the consistency of DCR between electrical cabinets can be improved, and the life of the container can be extended.

[0119] In this embodiment, each battery cell is classified according to the first DCR value of each battery cell, and finally n battery cells belonging to the same gear are assembled into a battery pack. This method has simple control steps and convenient operation, and can also improve the consistency of DCR between battery cells in the battery pack.

[0120] It should be noted that the first DCR value of each battery cell among the n battery cells can be obtained through testing or calculated by other means. For example, for the battery cells assembled into an electrical box, the first DCR value of each battery cell can be obtained through testing. Another example is that for the electrical boxes assembled into an electrical cabinet, the first DCR value of each electrical box can be obtained through testing or by calculating the sum of the first DCR values of the battery cells included in each electrical box.

[0121] In some embodiments, as Figure 9 shown, S105, that is, obtaining the first DC resistance value of each of the n battery cells, includes: S101, obtaining the second DC resistance value of each of the n battery cells; S102, performing temperature correction and / or time correction on the second DC resistance value of each battery cell to obtain the first DC resistance value of each battery cell.

[0122] Generally, the DCR value of a battery cell shows an increasing trend with the storage time. After the battery cells are produced, they need to be stored in a warehouse for a period of time before being assembled into a battery pack. The inconsistent storage time results in inconsistent increases in the DCR values of the battery cells. Therefore, the DCR value obtained after the battery cells are produced cannot accurately represent the DCR value when they are assembled into a battery pack. It should be understood that the first DCR value and the second DCR value in the embodiments of the present application represent DCR values obtained at different times, and the time to obtain the second DCR value is earlier than the time to obtain the first DCR value. In addition, the second DCR value can refer to the DCR value obtained at any time during or after the production of the battery cell. Optionally, the second DCR value is the initial DCR value obtained by testing after the battery system is produced.

[0123] When assembling multiple battery cells into a battery pack, the control system can control the code scanning device to scan the identifier of the battery cell to obtain the second DCR value of the battery cell. By scanning the identifier of the battery cell, the time to obtain the second DCR value of the battery cell can also be traced. When the second DCR value is the initial DCR value, the time to obtain the first DCR value of the battery cell can also be referred to as the time when the battery cell enters the warehouse. Combining with the current time, the storage time of the battery cell can be obtained. For example, the storage time of the battery cell = current time - the time when the battery cell enters the warehouse. After obtaining the storage time of the battery cell and the second DCR value of the battery cell, the first DCR value of the battery cell, which can also be referred to as the current DCR value, can be calculated based on the relationship stored inside the control system.

[0124] Generally, a relationship between the DCR of a battery cell and the storage time of the battery cell can be stored inside the control system. This relationship can be obtained by the control system executing Method 100 to fit a series of DCR values with different storage times, or it can be obtained from another control system, that is, the relationship is obtained by another control system fitting a series of DCR values with different storage times and then sent by the other control system to the control system executing Method 100.

[0125] Optionally, multiple mass-produced battery cells can be selected for storage in a warehouse environment, and a series of different storage days can be selected. Every n days, the same process of DCR testing is performed on multiple battery cells of the same batch, and the average value of the DCR values of multiple battery cells of the same batch at the same storage time is calculated to obtain a series of DCR values of battery cells with different storage times. Next, the DCR values of battery cells with a series of different storage times are fitted according to "storage days, DCR value" to obtain the relationship between the DCR value of the battery cell and the storage time of the battery cell. Figure 10 The fitting schematic diagram of the DCR value and the storage time of battery cells of the same batch is shown.

[0126] In some embodiments, there is a relationship between the DCR value of battery cells in the same batch and the storage time of the battery cells. The relationship between the DCR values of battery cells in different batches and the storage time of the battery cells can be different. In other words, when correcting the DCR value of a certain battery cell for time, it is necessary to first determine the batch of the battery cell, and then further based on the relationship corresponding to that batch, substitute the storage time of the battery cell to determine the first DCR value of the battery cell.

[0127] In other embodiments, it is also possible to fit the DCR values obtained by testing different batches of battery cells at different storage times, that is, there is a corresponding relationship between the DCR value of any batch of battery cells and the storage time of the battery cells. In other words, when correcting the DCR value of a certain battery cell, it is not necessary to determine the batch of the battery cell, and directly based on the relationship stored inside the control system, substitute the storage time of the battery cell to determine the first DCR value of the battery cell.

[0128] In addition, the DCR value of the battery cell is also related to temperature. The DCR values of battery cells obtained at different temperatures vary greatly and cannot reflect the true differences between battery cells. Therefore, it is necessary to eliminate the data influence brought by temperature. For example, the second DCR values of different battery cells obtained at different temperatures can be corrected to the first DCR value at the same temperature, so that the differences in the first DCR values between all battery cells are not affected by temperature. This same temperature can be a reference temperature, such as 25°C, or this same temperature can also be the current ambient temperature.

[0129] Similarly, a relationship between the DCR of the battery cell and temperature can be stored inside the control system. When the test temperature of the battery cell and the second DCR value at the test temperature are obtained, combined with the reference temperature or the current ambient temperature, the first DCR value of the battery cell is calculated.

[0130] In some embodiments, the correction of the DCR value of the battery cell can be to first perform time correction and then temperature correction. For example, the initial DCR value obtained when the battery cell is produced can be corrected for time first, and then the initially DCR value corrected for time can be corrected for temperature, and finally the first DCR value when assembled into a battery pack is obtained. At this time, the second DCR value can actually be understood as the initially DCR value corrected for time.

[0131] In some other embodiments, the correction of the DCR value of the battery cell can also be to first perform temperature correction and then perform time correction. For example, the initial DCR value obtained when the battery cell is produced can be first corrected for temperature, and then the initially temperature-corrected DCR value can be corrected for time, and finally the first DCR value when assembled into a battery pack is obtained. At this time, the second DCR value can actually be understood as the initially temperature-corrected DCR value.

[0132] In this embodiment, the second DCR value of the obtained battery cell is corrected for time and / or temperature to obtain the first DCR value of the battery cell. Furthermore, the first DCR value of the battery cell can be used as a basis for determining whether it can be assembled into a battery pack, making the DCR control of the battery pack more accurate and improving the consistency of the DCR between the battery cells in the battery pack.

[0133] Optionally, as Figure 11 shown, S101, that is, obtaining the second DC resistance value of each of the n battery cells, includes: S103, performing a DC resistance test on each battery cell at the test temperature to obtain the second DC resistance value of each battery cell; S102, that is, correcting the second DC resistance value of each battery cell for temperature and / or time to obtain the first DC resistance value of each battery cell, includes: S104, correcting the second DC resistance value obtained at the test temperature to the first DC resistance value at the reference temperature.

[0134] For example, the second DCR value of each battery monomer can be obtained through testing, and the second DCR value and the test temperature are recorded. When assembling the electrical box, the control system can scan the identification of the battery monomer to obtain the corresponding second DCR value and the test temperature. Further, based on the test temperature and the reference temperature, the second DCR value can be corrected to the first DCR value at the reference temperature. Optionally, the reference temperature is 25 °C.

[0135] In this embodiment, correcting the second DCR value at the test temperature to the first DCR value at the reference temperature can make the first DCR values of multiple battery cells all correspond to the same temperature, eliminating the influence of temperature on the difference in the first DCR values between battery cells, thus providing a reliable basis for the consistency judgment of DCR.

[0136] Optionally, as Figure 12As shown in S104, correcting the second DCR value obtained at the test temperature to the first DCR value at the reference temperature includes: S106, correcting the second DC resistance value to the first DC resistance value according to the ratio between the first function value and the second function value, where the first function value and the second function value are values obtained by substituting the reference temperature and the test temperature into the first mapping function of the DC resistance value and the temperature respectively.

[0137] For example, the second DCR value obtained at the test temperature can be corrected to the first DCR value at the reference temperature according to the following formula:

[0138] R1 = f(T0) / f(T1) * R2 (3).

[0139] Wherein, R1 is the first DCR value, R2 is the second DCR value, T0 is the reference temperature, T1 is the test temperature, and f(T0) and f(T1) are values obtained by substituting the reference temperature and the test temperature into the first mapping function of the DCR value and the temperature respectively.

[0140] As mentioned above, a correspondence or mapping function between the DCR value and the temperature can be stored inside the control system. This correspondence or mapping function can be obtained by data fitting. Taking the battery cells forming an electric box as an example, specifically, all the DCR test values and the corresponding test temperatures of the battery cells in the production line in the past month can be collected, and the DCR test values and the test temperatures of all the battery cells are fitted to obtain the first mapping function of the DCR value and the temperature.

[0141] In some embodiments, the first mapping function of the DCR value and the temperature f(t) = dt 2 + et + f, where d, e, f are constants, t represents the temperature and is a variable, and this mapping function can be updated or corrected regularly according to actual needs.

[0142] After the control system obtains the test temperature T1, the second DCR value DCR2, and the reference temperature T0 of the battery unit, first, T1 and T0 can be respectively substituted into the first mapping function of the DCR value and the temperature to obtain f(T1) and f(T0), and then substituted into the above formula (3), and then the first DCR value R1 of the battery unit can be calculated.

[0143] In some embodiments, such as Figure 13As shown, S102, that is, performing temperature correction and / or time correction on the second DCR value of each battery cell to obtain the first DCR value of each battery cell, includes: S107, correcting the second DC resistance value of each battery cell according to the ratio between the second DC resistance value of the reference battery cell and the first DC resistance value of the reference battery cell to obtain the first DC resistance value of each battery cell. The first DC resistance value of the reference battery cell is obtained by substituting the storage time of the reference battery cell and the second DC resistance value of the reference battery cell into the second mapping function between the DC resistance value and the storage time.

[0144] For example, the time correction of the second DCR value of each battery cell can be performed according to the following formula to obtain the first DCR value of each battery cell:

[0145] R3 = (aD 2 + bD + R0)*R4 / R0 (4).

[0146] Wherein, a and b are constants, R3 is the first DCR value of each battery cell, R4 is the second DCR value of each battery cell, R0 is the second DCR value of the reference battery cell, and D is the storage time of each battery cell.

[0147] That is to say, the second DCR value of one of the battery cells and the storage days of the battery cell can be obtained first, and the first DCR value of the battery cell can be calculated according to the second mapping function of the DCR value and the storage days. The first DCR values of other battery cells can be obtained by correcting the first DCR value of the previously obtained battery cell. Assuming that the first DCR value of the previously obtained battery cell is denoted as R0', its second DCR value is denoted as R0, the first DCR value of the currently required battery cell to be calculated is denoted as R3, and its second DCR value is denoted as R4, then DCR3 is obtained by R4*R0' / R0.

[0148] It should be noted that usually, the DCR test will be immediately performed during or after the production of the battery cells, that is, the second DCR value is obtained and bound to the identification of the battery cell. And the first DCR value will be immediately obtained after the battery cells are assembled into a battery pack to obtain the DCR value of the battery pack and bind it to the identification of the battery pack. At the same time, the first DCR value of the battery cell can also be bound to the identification of the battery cell. Therefore, when calculating the first DCR value of a certain battery cell using formula (3), it is necessary to ensure that the reference battery cell and this battery cell are produced or assembled at the same time and assembled into a battery pack at the same time.

[0149] For example, the DCR test time of battery cells in the same batch on the production line is September 1, 2023, and the time when the battery cells are assembled into an electrical box is September 15, 2023. One battery cell in this batch is used as a reference battery cell. The second DCR value, i.e., the initial DCR value, obtained by testing the reference battery cell on the production line is 0.5523 mΩ. The DCR value of the reference battery cell when assembled into the electrical box calculated by substituting into the fitting relationship between the DCR value and the storage days is 0.59 mΩ. The initial DCR value of another battery cell in this batch obtained by testing on the production line is 0.56 mΩ. Then the DCR value of this battery cell when assembled into the electrical box is 0.59 * 0.56 / 0.5523 = 0.598 mΩ.

[0150] In this embodiment, by correcting the first DCR value of the obtained battery cells, the first DCR values of other battery cells can be obtained quickly and accurately, reducing the calculation amount and improving the processing efficiency of the control system.

[0151] In some other embodiments, as Figure 13 shown, S102, that is, performing temperature correction and / or time correction on the second DCR value of each battery cell to obtain the first DCR value of each battery cell, includes: S108, substituting the storage time of each battery cell and the second DC resistance of each battery cell into the third mapping function between the DC resistance value and the storage time to obtain the first DC resistance value of each battery cell.

[0152] For example, according to the following formula, time correction can be performed on the second DCR value of each battery cell to obtain the first DCR value of each battery cell:

[0153] R6 = aD 2 + bD + c + R5 (5).

[0154] Where a, b, and c are constants, R6 is the first DCR value of each battery cell, R5 is the second DCR value of each battery cell, and D is the storage time of each battery cell. The above formula (5) can also be referred to as the third mapping function between the DCR value and the storage time.

[0155] Using the above formula (5) to obtain the first DCR value of each battery cell is not affected by the time when the battery cell obtains the second DCR value and the time when it is assembled into the battery pack. That is, once the second DCR value and its storage time of the battery cell are obtained, substituting them into the above formula (5) can obtain the first DCR value of the battery cell.

[0156] In this embodiment, by directly substituting the second DCR value of the battery cell and the storage time of the battery cell into the relational expression, the first DCR value of the battery cell can be accurately obtained without being affected by other battery cells, and the calculation method is flexible.

[0157] Next, the method 200 for assembling an electric cabinet provided by the embodiments of the present application will be described in detail in conjunction with Figure 14 and the method 300 for assembling an electric box provided by the embodiments of the present application will be described in detail in conjunction with Figure 15 。

[0158] As Figure 14 shown, the method 200 includes the following parts or all of the content.

[0159] S201, the electric box enters the assembly production line.

[0160] S202, scan the identifier of the electric box to obtain the DCR x of the electric box and the lower bin time of the electric box;

[0161] S203, calculate the storage time of the electric box.

[0162] S204, perform time correction on the DCR x of the electric box to obtain the DCR y of the electric box.

[0163] S205, perform temperature correction on the DCR y of the electric box to obtain the DCR z of the electric box.

[0164] S206, accumulate the DCR z of n electric boxes to obtain G = DCR z1 + DCR z2 + DCR z3 +,..., + DCR zn 。

[0165] S207, determine whether G is within [DCR 下限 , DCR 上限 .

[0166] S208, if it is determined that G is within [DCR 下限 , DCR 上限 , then assemble n electric boxes into an electric cabinet and produce normally.

[0167] S209, if it is determined that G is not within [DCR 下限 , DCR 上限 , replace the nth electric box with the (n + 1)th electric box and continue to accumulate DCR, and at the same time return the nth electric box to the initial end of the assembly production line.

[0168] As shown Figure 15 in, method 300 includes some or all of the following steps.

[0169] S301, A battery cell enters the assembly line.

[0170] S302, Scan the identification of the battery cell to obtain the DCR of the battery cell x and the lower bin time of the battery cell;

[0171] S303, Calculate the storage time of the battery cell.

[0172] S304, Perform time correction on the DCR of the battery cell x to obtain the DCR of the battery cell y .

[0173] S305, Perform temperature correction on the DCR of the battery cell y to obtain the DCR of the battery cell z .

[0174] S306, Based on the DCR of the battery cell z , determine whether the battery cell belongs to the S grade.

[0175] S307, If the battery cell belongs to the S grade, assemble n battery cells belonging to the S grade into an electrical box.

[0176] S308, Mark the electrical box assembled in S307 as the S grade.

[0177] S309, If the battery cell does not belong to the S grade, then continue to determine whether the battery cell belongs to the T grade based on the DCR of the battery cell z .

[0178] S310, If the battery cell belongs to the T grade, assemble n battery cells belonging to the T grade into an electrical box.

[0179] S311, Mark the electrical box assembled in S310 as the T grade.

[0180] S312, If the battery cell does not belong to the T grade, then continue to determine whether the battery cell belongs to the U grade based on the DCR of the battery cell z .

[0181] S313, If the battery cell belongs to the U grade, assemble n battery cells belonging to the U grade into an electrical box.

[0182] S314, Mark the electrical box assembled in S313 as the U grade.

[0183] S315, If the battery cell does not belong to the U grade, then discharge the battery cell to the scrap area.

[0184] It should be understood that in various embodiments of the present application, the magnitudes of the serial numbers of the above processes do not imply the order of execution, and the order of execution of each process should be determined according to its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present application. For example, S204 may be executed after S205, and for another example, S304 may be executed after S305.

[0185] The method for assembling a battery pack according to the embodiments of the present application has been described in detail above. Next, in conjunction with Figure 16 and Figure 17 the device for assembling a battery pack according to the embodiments of the present application will be described in detail. The technical features described in the method embodiments are applicable to the following device embodiments.

[0186] Figure 16 FIG. shows a schematic block diagram of a device 400 for assembling a battery pack according to an embodiment of the present application. As Figure 16 shown, the device 400 includes the following parts or all of the content.

[0187] A determination unit 410, configured to determine whether the DC resistances of n battery cells satisfy a first condition, where n is a positive integer greater than 1;

[0188] An assembly unit 420, configured to assemble n battery cells into a battery pack when the DC resistances of the n battery cells satisfy the first condition.

[0189] In a possible embodiment, as Figure 17 shown, the device 400 further includes: an acquisition unit 430, configured to acquire the first DC resistance value of each of the n battery cells; wherein, the determination unit 410 is specifically configured to: determine whether the sum of the first DC resistance values of the n battery cells is within a first preset range.

[0190] In a possible embodiment, n battery cells enter the assembly line continuously.

[0191] In a possible embodiment, at least two adjacent battery cells among the n battery cells do not enter the assembly line continuously.

[0192] In a possible embodiment, the determination unit 410 is specifically configured to: when the sum of the first DC resistance values of m battery cells that enter the assembly line continuously is not within the first preset range, determine whether the sum of the first DC resistance values of the n battery cells is within the first preset range, where the n battery cells include (m - i) battery cells among the m battery cells and the first i battery cells that enter the assembly line after the m battery cells, and i is a positive integer less than m.

[0193] In a possible embodiment, as Figure 17As shown, the device 400 further includes: a control unit 440, configured to control i battery cells among the m battery cells, except for (m - i) battery cells, to circulate through the abnormal battery cell channel and enter the assembly production line.

[0194] In a possible embodiment, the i battery cells among the m battery cells are closer to the abnormal battery cell channel than the (m - i) battery cells.

[0195] In a possible embodiment, i = 1.

[0196] In a possible embodiment, as Figure 17 shown, the device 400 further includes: an acquisition unit 430, configured to acquire the first DC resistance value of each of the n battery cells; wherein, the determination unit 410 is specifically configured to: determine whether the first DC resistance value of each of the n battery cells is within a second preset range.

[0197] In a possible embodiment, the acquisition unit 430 is specifically configured to: acquire the second DC resistance value of each of the n battery cells; perform temperature correction and / or time correction on the second DC resistance value of each battery cell to obtain the first DC resistance value of each battery cell.

[0198] In a possible embodiment, the acquisition unit 430 is specifically configured to: perform a DC resistance test on each battery cell at a test temperature to obtain the second DC resistance value of each battery cell; correct the second DC resistance value obtained at the test temperature to the first DC resistance value at a reference temperature.

[0199] In a possible embodiment, the acquisition unit 430 is specifically configured to: correct the second DC resistance value to the first DC resistance value according to the ratio between the first function value and the second function value, where the first function value and the second function value are values obtained by substituting the reference temperature and the test temperature into the first mapping function of the DC resistance value and the temperature.

[0200] In a possible embodiment, the acquisition unit 430 is specifically configured to: correct the second DC resistance value of each battery cell according to the ratio between the second DC resistance value and the first DC resistance value of a reference battery cell to obtain the first DC resistance value of each battery cell, where the first DC resistance value of the reference battery cell is obtained by substituting the storage time of the reference battery cell and the second DC resistance value of the reference battery cell into the second mapping function of the DC resistance value and the storage time.

[0201] In a possible embodiment, the obtaining unit 430 is specifically configured to: substitute the storage time of each battery cell and the second DC resistance of each battery cell into a third mapping function of the DC resistance value and the storage time, so as to obtain the first DC resistance value of each battery cell.

[0202] In a possible embodiment, the battery pack is an electrical box and the battery cell is a battery monomer; or, the battery pack is an electrical cabinet and the battery cell is an electrical box.

[0203] It should be understood that each of the above modules in the device 400 is used to implement Figures 2 to 15 the corresponding processes in each of the methods in

[0204] Figure 18 FIG. shows a schematic block diagram of a control system 500 for assembling a battery pack according to an embodiment of the present application. As Figure 18 shown, the control system 500 includes a processor 510 and a memory 520. Among them, the memory 520 is used to store instructions, and the processor 510 is used to read the instructions and execute the methods of various embodiments of the present application based on the instructions.

[0205] Among them, the memory 520 may be a separate device independent of the processor 510, or may be integrated in the processor 510.

[0206] Optionally, as Figure 18 shown, the control system 500 may further include a transceiver 530, and the processor 510 may control the transceiver 530 to communicate with other devices. Specifically, it may send information or data to other devices, or receive information or data sent by other devices.

[0207] It should be understood that the processor in the embodiments of the present application may be an integrated circuit chip with the ability to process signals. In the implementation process, each step of the above method embodiments can be completed by the integrated logic circuit in the hardware of the processor or the instructions in the form of software. The above-mentioned processor may be a general-purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. It can implement or execute various methods, steps, and logic block diagrams disclosed in the embodiments of the present application. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc. The steps of the method disclosed in combination with the embodiments of the present application can be directly embodied as being executed by the hardware decoding processor, or completed by the combination of the hardware and software modules in the decoding processor. The software module may be located in a mature storage medium in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, etc. This storage medium is located in the memory, and the processor reads the information in the memory and combines its hardware to complete the steps of the above method.

[0208] It can be understood that the memory in the embodiments of the present application can be a volatile memory or a non-volatile memory, or can include both volatile and non-volatile memories. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory can be a random access memory (RAM), which is used as an external cache. By way of example but not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchlink dynamic random access memory (SLDRAM), and direct rambus random access memory (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to include but not be limited to these and any other suitable types of memory.

[0209] The embodiments of the present application also provide a computer-readable storage medium for storing a computer program.

[0210] Optionally, the computer-readable storage medium can be applied to the control system of the assembled battery pack in the embodiments of the present application, and the computer program causes the computer to execute the corresponding processes implemented by the control system in each of the methods of the embodiments of the present application. For the sake of brevity, details are not described herein again.

[0211] The embodiments of the present application also provide a computer program product including computer program instructions.

[0212] Optionally, the computer program product can be applied to the control system of the assembled battery pack in the embodiments of the present application, and the computer program instructions cause the computer to execute the corresponding processes implemented by the control system in each of the methods of the embodiments of the present application. For the sake of brevity, details are not described herein again.

[0213] The embodiments of the present application also provide a computer program.

[0214] Optionally, the computer program can be applied to the control system for assembling a battery pack in the embodiments of the present application. When the computer program runs on a computer, it causes the computer to execute the corresponding processes implemented by the control system in each method of the embodiments of the present application. For the sake of brevity, it will not be described in detail here.

[0215] In several embodiments provided by the present application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces. The indirect couplings or communication connections of the devices or units can be in electrical, mechanical, or other forms.

[0216] The units described as separate components may or may not be physically separated. The components displayed as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0217] In addition, in each embodiment of the present application, the functional units can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit.

[0218] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions to cause a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in each embodiment of the present application. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, ROM, RAM, magnetic disks, or optical discs that can store program codes.

[0219] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of changes or substitutions, which should all be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for assembling a battery pack, characterized in that, Including: Determine whether the DC resistances of n battery cells satisfy a first condition, where n is a positive integer greater than 1; When the DC resistances of the n battery cells satisfy the first condition, assemble the n battery cells into the battery pack.

2. The method according to claim 1, wherein The method further includes: Obtain a first DC resistance value of each of the n battery cells; Wherein, the determining whether the DC resistances of the n battery cells satisfy the first condition includes: Determine whether the sum of the first DC resistance values of the n battery cells is within a first preset range.

3. The method according to claim 2, wherein The n battery cells continuously enter an assembly production line.

4. The method according to claim 2, wherein At least two adjacent battery cells among the n battery cells do not continuously enter the assembly production line.

5. The method according to claim 4, wherein The determining whether the sum of the first DC resistance values of the n battery cells is within the first preset range includes: When the sum of the first DC resistance values of m battery cells that continuously enter the assembly production line is not within the first preset range, determine whether the sum of the first DC resistance values of the n battery cells is within the first preset range, where the n battery cells include (m - i) battery cells among the m battery cells and the first i battery cells that enter the assembly production line after the m battery cells, m = n, and i is a positive integer less than m.

6. The method according to claim 5, wherein The method further includes: Control i battery cells among the m battery cells except the (m - i) battery cells to circularly enter the assembly production line through an abnormal battery cell channel.

7. The method according to claim 6, wherein The i battery cells among the m battery cells are closer to the abnormal battery cell channel than the (m - i) battery cells.

8. The method according to any one of claims 5 to 7, characterized in that i＝1。 9. The method according to claim 1, wherein The method further includes: Obtain a first DC resistance value of each of the n battery cells; Wherein, the determining whether the DC resistances of the n battery cells satisfy the first condition includes: Determine whether the first DC resistance value of each of the n battery cells is within a second preset range.

10. The method according to any one of claims 2 to 9, characterized in that, The obtaining the first DC resistance value of each of the n battery cells includes: Obtain a second DC resistance value of each of the n battery cells; Perform temperature correction and / or time correction on the second DC resistance value of each battery cell to obtain the first DC resistance value of each battery cell.

11. The method according to claim 10, wherein The obtaining the second DC resistance value of each of the n battery cells includes: Perform a DC resistance test on each battery cell at a test temperature to obtain the second DC resistance value of each battery cell; The performing temperature correction on the second DC resistance value of each battery cell to obtain the first DC resistance value of each battery cell includes: Correct the second DC resistance value obtained at the test temperature to the first DC resistance value at a reference temperature.

12. The method according to claim 11, wherein The correcting the second DC resistance value obtained at the test temperature to the first DC resistance value at a reference temperature includes: The second DC resistance value is corrected to the first DC resistance value according to the ratio between the first function value and the second function value, where the first function value and the second function value are values obtained by substituting the reference temperature and the test temperature into a first mapping function of DC resistance value and temperature, respectively.

13. The method according to claim 10, wherein The time correction of the second DC resistance value of each battery cell to obtain the first DC resistance value of each battery cell includes: Correcting the second DC resistance value of each battery cell according to the ratio between the second DC resistance value and the first DC resistance value of a reference battery cell, to obtain the first DC resistance value of each battery cell, where the first DC resistance value of the reference battery cell is obtained by substituting the storage time of the reference battery cell and the second DC resistance value of the reference battery cell into a second mapping function of DC resistance value and storage time.

14. The method according to claim 10, wherein The time correction of the second DC resistance value of each battery cell to obtain the first DC resistance value of each battery cell includes: Substituting the storage time of each battery cell and the second DC resistance of each battery cell into a third mapping function of DC resistance value and storage time, to obtain the first DC resistance value of each battery cell.

15. The method according to any one of claims 1 to 14, characterized in that, The battery pack is an electrical box, and the battery cell is a battery monomer; or, the battery pack is an electrical cabinet, and the battery cell is an electrical box.

16. An apparatus for assembling a battery pack, characterized in that, It includes: A determination unit, configured to determine whether the DC resistances of n battery cells meet a first condition, where n is a positive integer greater than 1; An assembly unit, configured to assemble the n battery cells into the battery pack when the DC resistances of the n battery cells meet the first condition.

17. The device according to claim 16, characterized in that, The device further includes: An acquisition unit, configured to acquire the first DC resistance value of each battery cell among the n battery cells; Wherein, the determination unit is specifically configured to: Determine whether the sum of the first DC resistance values of the n battery cells is within a first preset range.

18. The device according to claim 17, wherein The n battery cells enter the assembly line continuously.

19. The device according to claim 17, characterized in that, At least two adjacent battery cells among the n battery cells do not enter the assembly line continuously.

20. The device according to claim 19, wherein, The determination unit is specifically configured to: When the sum of the first DC resistance values of m battery cells that enter the assembly line continuously is not within the first preset range, determine whether the sum of the first DC resistance values of the n battery cells is within the first preset range, where the n battery cells include (m - i) battery cells among the m battery cells and the first i battery cells that enter the assembly line after the m battery cells, m = n, and i is a positive integer less than m.

21. The device according to claim 20, wherein The device further includes: A control unit, configured to control the i battery cells other than the (m - i) battery cells among the m battery cells to enter the assembly line cyclically through an abnormal battery cell channel.

22. The device according to claim 21, characterized in that, The i battery cells among the m battery cells are closer to the abnormal battery cell channel than the (m - i) battery cells.

23. The device according to any one of claims 20 to 22, characterized in that, i＝1。 24. The device according to claim 16, characterized in that The device further includes: an acquisition unit configured to acquire a first DC resistance value of each of the n battery cells; wherein the determination unit is specifically configured to: determine whether the first DC resistance value of each of the n battery cells is within a second preset range.

25. The device according to any one of claims 17 to 24, characterized in that The acquisition unit is specifically configured to: acquire a second DC resistance value of each of the n battery cells; perform temperature correction and / or time correction on the second DC resistance value of each battery cell to obtain the first DC resistance value of each battery cell.

26. The device according to claim 25, characterized in that, The acquisition unit is specifically configured to: perform a DC resistance test on each battery cell at a test temperature to obtain the second DC resistance value of each battery cell; correct the second DC resistance value obtained at the test temperature to the first DC resistance value at a reference temperature.

27. The device according to claim 26, characterized in that, The acquisition unit is specifically configured to: correct the second DC resistance value to the first DC resistance value according to the ratio between a first function value and a second function value, where the first function value and the second function value are values obtained by substituting the reference temperature and the test temperature into a first mapping function of the DC resistance value and the temperature.

28. The device according to claim 25, characterized in that The acquisition unit is specifically configured to: correct the second DC resistance value of each battery cell according to the ratio between the second DC resistance value of a reference battery cell and the first DC resistance value of the reference battery cell to obtain the first DC resistance value of each battery cell, where the first DC resistance value of the reference battery cell is obtained by substituting the storage time of the reference battery cell and the second DC resistance value of the reference battery cell into a second mapping function of the DC resistance value and the storage time.

29. The device according to claim 25, characterized in that, The acquisition unit is specifically configured to: substitute the storage time of each battery cell and the second DC resistance of each battery cell into a third mapping function of the DC resistance value and the storage time to acquire the first DC resistance value of each battery cell.

30. The device according to any one of claims 16 to 29, characterized in that, The battery pack is an electrical box and the battery cell is a battery monomer; or, the battery pack is an electrical cabinet and the battery cell is an electrical box.

31. A control system for assembling a battery pack, characterized in that, including: a memory configured to store instructions; a processor configured to read the instructions and execute the method according to any one of claims 1 to 15 based on the instructions.

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