Device and method for adjusting flatness of battery cell

Abstract

The invention discloses a device and a method for adjusting the flatness of a battery cell. The device for adjusting the flatness of the battery cell comprises a clamp and a controller, the clamp is used for clamping a battery cell, a plurality of temperature control components are arranged on a temperature control surface of the clamp, the temperature control surface is in contact with a cooling surface of the battery cell under the condition that the clamp clamps the battery cell, the cooling surface comprises a plurality of partitions, and the partitions and the temperature control components are arranged in a one-to-one correspondence manner; the controller is used for controlling the first temperature control part to cool the target subarea according to a target cooling curve corresponding to the target subarea in the process that the clamp clamps the battery cell so as to reduce the flatness of the target subarea, the target subarea is any subarea in the multiple subareas, and the first temperature control part is used for controlling the first temperature control part to cool the target subarea; the target cooling part is the cooling part corresponding to the target partition in the multiple cooling parts. Therefore, the temperature of the battery cell can be reduced before the battery cell is sealed, and the internal and external temperature difference after the battery cell is sealed is reduced, so that the internal and external air pressure difference is reduced, the concave degree of the surface of the battery cell is reduced, and the flatness of the battery cell is improved.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to a battery cell flatness adjustment device and method. Background Technology

[0002] After the battery cell is formed, the internal temperature is high. After the battery cell is sealed by welding at high temperature, as the battery cell gradually cools down and the internal air pressure decreases, the external air pressure gradually becomes greater than the internal air pressure, causing the shell to be under continuous stress. This causes the surface of the battery cell to become concave, resulting in flatness exceeding the specifications.

[0003] If the flatness of the battery cell exceeds the specification, it may lead to problems such as glue cracking, solder burn-through, poor heat dissipation, and short lifespan. Therefore, a solution to improve the flatness of the battery cell is needed.

[0004] Therefore, a solution is needed that enables the recognition rate of the graphic codes on the battery to meet production requirements.

[0005] The above statements are for the purpose of providing background information in relation to this application only and do not necessarily constitute prior art. Summary of the Invention

[0006] In view of the above problems, this application provides a battery cell flatness adjustment device and method, which can reduce the battery cell temperature before sealing the battery cell, reduce the internal and external temperature difference after sealing the battery cell, thereby reducing the internal and external air pressure difference, reducing the degree of concavity of the battery cell surface, and thus improving the flatness of the battery cell.

[0007] In a first aspect, this application provides a battery production system, which includes: a clamp and a controller; the clamp for clamping a battery cell, the clamp having a temperature control surface with multiple temperature control components, each of which is connected to the controller, wherein when the clamp is clamping the battery cell, the temperature control surface is in contact with the cooling surface of the battery cell, the cooling surface including multiple partitions, each partition corresponding to one of the multiple temperature control components; the controller for controlling a first temperature control component to cool a target partition according to a target cooling curve corresponding to the target partition during the clamping process, so as to reduce the flatness of the target partition, the target partition being any one of the multiple partitions, and the target cooling component being the cooling component corresponding to the target partition among the multiple cooling components.

[0008] In this embodiment, the temperature control surface of the clamp is equipped with multiple temperature control components, and the cooling surface of the battery cell includes multiple zones. Each zone corresponds to one of the multiple temperature control components. During the clamping process, the temperature control surface of the clamp contacts the cooling surface of the battery cell. The controller can control the multiple temperature control components to cool each zone according to its corresponding cooling curve. This reduces the battery cell temperature before sealing, decreases the internal and external temperature difference after sealing, reduces the internal and external pressure difference, and minimizes surface concavity, thereby improving the flatness of the battery cell. Furthermore, different areas on the cooling surface have different flatness requirements, necessitating different adjustments. By assigning multiple temperature control components to each zone, each zone can be independently and precisely temperature-controlled to meet the differentiated needs of different zones, thus improving the flatness of the battery cell more accurately.

[0009] In some embodiments, the cell flatness adjustment device further includes: a plurality of rangefinders, each connected to a controller, wherein the plurality of rangefinders are configured to correspond one-to-one with a plurality of partitions; a target rangefinder is used to detect the height of a target partition and send the height to the controller, wherein the target rangefinder is the rangefinder corresponding to the target partition among the plurality of rangefinders; the controller is used to determine the target flatness error of the target partition based on the height; and to determine the target cooling curve of the target partition based on the target flatness error.

[0010] In this way, by setting up multiple rangefinders that correspond one-to-one with multiple zones, the height of each zone can be accurately determined, laying the foundation for independent zone temperature control.

[0011] In some embodiments, the temperature control surface is further provided with multiple temperature sensors, which are respectively connected to the controller, and the multiple temperature sensors are configured to correspond one-to-one with multiple partitions; the target temperature sensor is used to detect the current temperature of the target partition and send the current temperature to the controller, and the target temperature sensor is the temperature sensor among the multiple temperature sensors that corresponds to the target partition; the controller is used to determine the target cooling curve of the target partition based on the current temperature.

[0012] In this way, by setting multiple temperature sensors and corresponding them one-to-one with multiple zones, the current temperature of each zone can be accurately detected, laying the foundation for independent zone temperature control.

[0013] In some embodiments, the plurality of partitions include at least two of the following: the tab side region of the cell, the winding and closing region, the stacked and misaligned region, and the central region.

[0014] Typically, areas such as the tab side, winding and sealing area, stacking misalignment area, and center area of ​​a battery cell are prone to concavity. Therefore, setting these areas as partitions and cooling them can effectively improve the flatness of the battery cell.

[0015] In some embodiments, the temperature control component includes a thermoelectric cooler, the cold end of which is disposed on the temperature control surface.

[0016] Thus, the semiconductor cooler is small in size, making it easy to integrate multiple semiconductor coolers on the fixture to achieve independent zone temperature control. In addition, the semiconductor cooler has high temperature control accuracy, which makes it easy to accurately cool the battery cell.

[0017] In some embodiments, the hot end of the thermoelectric cooler is provided with a heat dissipation layer.

[0018] In this way, by setting a heat dissipation layer at the hot end of the semiconductor cooler, the heat accumulated at the hot end can be dissipated efficiently, so as to avoid the safety hazards caused by excessive temperature.

[0019] In some embodiments, a first thermally conductive layer is provided between the hot end of the semiconductor cooler and the heat dissipation layer.

[0020] Thus, by placing a first thermally conductive layer between the hot end of the semiconductor cooler and the heat dissipation layer, thermal resistance can be reduced, heat conduction can be accelerated, and heat dissipation efficiency can be improved.

[0021] In some embodiments, the first thermally conductive layer is thermally conductive silicone grease or indium foil.

[0022] Thus, thermal grease is inexpensive, and choosing thermal grease as the first thermal conductive layer can reduce costs; indium foil has low thermal resistance, and choosing indium foil as the first thermal conductive layer can improve thermal conductivity.

[0023] In some embodiments, a second thermally conductive layer is provided between the cold end of the semiconductor cooler and the cooling surface.

[0024] Thus, by placing a second heat-conducting layer between the cold end and the cooling surface of the semiconductor cooler, thermal resistance can be reduced, heat conduction can be accelerated, and cooling efficiency can be improved.

[0025] In some embodiments, the second thermally conductive layer is thermally conductive silicone grease or indium foil.

[0026] Thus, thermal grease is inexpensive, and choosing it as the first thermal conductive layer can reduce costs. Moreover, thermal grease is insulating, which can reduce the probability of short circuits caused by conductivity between the charged battery cell and the clamp. Indium foil has low thermal resistance, and choosing it as the first thermal conductive layer can improve thermal conductivity.

[0027] In some embodiments, an insulating layer is provided between the cold end of the semiconductor cooler and the cooling surface.

[0028] Thus, by setting an insulating layer between the cold end and the cooling surface, the probability of a short circuit caused by conductivity between the charged battery cell and the clamp can be reduced.

[0029] Secondly, this application provides a method for adjusting the flatness of a battery cell, comprising: obtaining a target cooling curve corresponding to a target partition of the battery cell, wherein the cooling surface of the battery cell includes multiple partitions, and the target partition is any one of the multiple partitions; during the process of clamping the battery cell with a fixture, controlling a target temperature control component to cool the target partition according to the target cooling curve to reduce the flatness of the target partition; the temperature control surface of the fixture is provided with multiple temperature control components, and when the fixture clamps the battery cell, the temperature control surface is in contact with the cooling surface, and the multiple partitions are set one-to-one with the multiple temperature control components, wherein the target cooling component is the cooling component corresponding to the target partition among the multiple cooling components.

[0030] In this embodiment, the temperature control surface of the clamp is equipped with multiple temperature control components, and the cooling surface of the battery cell includes multiple zones. Each zone corresponds to one of the multiple temperature control components. During the clamping process, the temperature control surface of the clamp contacts the cooling surface of the battery cell. The controller can control the multiple temperature control components to cool each zone according to its corresponding cooling curve. This reduces the battery cell temperature before sealing, decreases the internal and external temperature difference after sealing, reduces the internal and external pressure difference, and minimizes surface concavity, thereby improving the flatness of the battery cell. Furthermore, different areas on the cooling surface have different flatness requirements, necessitating different adjustments. By assigning multiple temperature control components to each zone, each zone can be independently and precisely temperature-controlled to meet the differentiated needs of different zones, thus improving the flatness of the battery cell more accurately.

[0031] In some embodiments, obtaining the target cooling curve corresponding to the target partition of the battery cell includes: obtaining a first mapping relationship between the partition and the cooling curve; and determining the target cooling curve corresponding to the target partition based on the first mapping relationship.

[0032] In this way, the cooling curve corresponding to any partition can be quickly determined based on the first mapping relationship between the partition and the cooling curve, which facilitates the rapid cooling of each partition.

[0033] In some embodiments, obtaining the target cooling curve corresponding to the target partition of the battery cell includes: obtaining a second mapping relationship between the flatness error and the cooling curve and the target flatness error of the target partition; and determining the target cooling curve corresponding to the target flatness error based on the second mapping relationship.

[0034] In this way, by obtaining the flatness error and the second mapping relationship of each partition, the cooling curve corresponding to each partition can be accurately determined based on the flatness error, thus facilitating precise cooling of each partition.

[0035] In some embodiments, obtaining the target cooling curve corresponding to the target partition of the battery cell includes: obtaining the current temperature, target desired temperature and preset duration of the target partition, wherein the preset duration is less than or equal to the duration for which the clamp holds the battery cell; and generating the target cooling curve based on the current temperature, target desired temperature and preset duration.

[0036] In this way, the temperature of the target zone can be reduced from the current temperature to the desired temperature during the transfer of the battery cell using a clamp, which improves the flatness of the battery cell without spending extra time.

[0037] In some embodiments, obtaining the target expected temperature of the target partition includes: obtaining a third mapping relationship between the partition and the expected temperature; and determining the target expected temperature corresponding to the target partition based on the third mapping relationship.

[0038] In this way, the desired temperature of any partition can be quickly determined based on the third mapping relationship between the partition and the desired temperature, which makes it easier to cool down each partition quickly.

[0039] In some embodiments, obtaining the target desired temperature of the target partition includes: obtaining the target flatness error and the current temperature of the target partition; determining the target temperature change of the target partition based on the target flatness error; and determining the target desired temperature based on the current temperature and the target temperature change.

[0040] In this way, the required temperature change for a partition can be accurately determined based on the partition's flatness error, and the target desired temperature for that partition can be accurately determined based on its current temperature and the temperature change.

[0041] In some embodiments, generating a target cooling curve based on the current temperature, the target desired temperature, and a preset duration includes: obtaining a fourth mapping relationship between flatness error and cooling curve type and the target flatness error of the target partition; determining the target cooling curve type corresponding to the target flatness error based on the fourth mapping relationship; and generating the target cooling curve based on the current temperature, the target desired temperature, the preset duration, and the target cooling curve type.

[0042] In this way, different cooling curve types can be used for zones with different flatness errors to achieve more precise dynamic temperature control of zones.

[0043] In some embodiments, during the process of clamping the battery cell, controlling the target temperature control component to cool the target partition according to the target cooling curve to reduce the flatness of the target partition includes: determining the electrical parameters of the target temperature control component based on the target cooling curve; and controlling the target temperature control component to cool the target partition based on the electrical parameters during the process of clamping the battery cell to reduce the flatness of the target partition.

[0044] In this way, by determining the electrical parameters of the temperature control components for each zone based on the cooling curves of each zone, the cooling rate of each zone can be adjusted, thereby achieving precise zone temperature control.

[0045] In some embodiments, electrical parameters include current or power.

[0046] In this way, by controlling the current or power of the temperature control components in each zone, the cooling rate of each zone can be controlled simply and accurately.

[0047] In some embodiments, after controlling the target temperature control component to cool the target partition according to the target cooling curve to reduce the flatness of the target partition, the method further includes: obtaining the target flatness of the target partition; controlling the sealing device to seal the battery cell based on the target flatness being less than or equal to a preset threshold; and controlling the sorting device to move the battery cell to the target area based on the target flatness being greater than the preset threshold.

[0048] In this way, cells that meet or do not meet the flatness standard can be handled automatically and properly, improving the level of automation in cell production.

[0049] In some embodiments, the above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, specific embodiments of this application are described below.

[0050] The beneficial effects of the embodiments of this application are at least as follows: (1) The temperature control component of the clamp can cool the battery cell during the clamping process, thereby reducing the battery cell temperature before sealing, reducing the internal and external temperature difference after sealing, thereby reducing the internal and external air pressure difference, reducing the degree of concavity of the battery cell surface, and thus improving the flatness of the battery cell. (2) By setting multiple temperature control components to correspond one-to-one with multiple zones of the cell cooling surface, the temperature of each zone can be controlled independently and precisely to adapt to the different needs of different zones, thereby improving the flatness of the cell more accurately. Attached Figure Description

[0051] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 One of the structural schematic diagrams of a cell flatness adjustment device provided in some embodiments of this application; Figure 2A schematic diagram of the structure of a rangefinder provided in some embodiments of this application; Figure 3 This is a second schematic diagram of a battery cell flatness adjustment device provided in some embodiments of this application; Figure 4 This is the third schematic diagram of a battery cell flatness adjustment device provided in some embodiments of this application; Figure 5 A schematic diagram of a semiconductor cooler provided for some embodiments of this application; Figure 6 A flowchart illustrating a method for adjusting the flatness of a battery cell, provided in some embodiments of this application; Figure 7 A schematic diagram of a zoned temperature control system provided in some embodiments of this application; Figure 8 This application provides a schematic diagram of the structure of a battery cell flatness adjustment system according to some embodiments; Figure 9 One of the schematic diagrams of a cooling curve provided for some embodiments of this application; Figure 10 This is a second schematic diagram of a cooling curve provided for some embodiments of this application.

[0052] The accompanying drawings are not necessarily drawn to scale. Detailed Implementation

[0053] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0054] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0055] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0056] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0057] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0058] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0059] The term "determine" can encompass a wide variety of actions. For example, "determine" can include calculation, operation, processing, deduction, investigation, searching (e.g., looking in a table, database, or other data structure), assertion, etc. Furthermore, "determine" can include receiving (e.g., receiving information), accessing (e.g., accessing data in memory), etc. Additionally, "determine" can include parsing, selecting, picking, building, etc.

[0060] In this document, the terms “coupled,” “connected,” and “linked” are used to refer to a direct or indirect connection between two objects. For example, when describing a first object coupled to a second object, the first object is considered to be coupled to the second object even if it is not in direct physical contact with the second object, but is indirectly in contact with the second object through a conductor and / or other objects. The term “circuit” is widely used and intended to include hardware implementations of both electronic components and conductors that, when connected and configured, enable the performance of the functions described in this application, without being limited to the type of electronic circuit.

[0061] In this application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged after being discharged to activate the active materials and continue to be used.

[0062] A battery cell typically consists of an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and an insulating component. During the charging and discharging process, active ions (e.g., lithium ions) repeatedly insert and extract between the positive and negative electrodes. The insulating component, positioned between the positive and negative electrodes, prevents short circuits while allowing active ions to pass through.

[0063] After the battery cell is formed, its internal temperature is high and its natural cooling rate is slow. After the battery cell is sealed with sealing nails at high temperature, as the battery cell gradually cools down and the internal air pressure decreases, the external air pressure gradually exceeds the internal air pressure. This causes the casing to be under continuous stress, resulting in concavity on the battery cell surface and thus exceeding the flatness specification. Exceeding the flatness specification of the battery cell may lead to problems such as adhesive cracking, solder burn-through, poor heat dissipation, and short lifespan. Therefore, a solution to improve the flatness of the battery cell is needed.

[0064] With the rapid development of the new energy industry, the demand for lithium-ion batteries is growing rapidly, placing higher demands on battery energy density. The thickness of square aluminum casings is becoming increasingly thinner, with the thinnest reaching 0.4mm. This thinner casing corresponds to lower tensile strength, making the cells more susceptible to temperature or internal / external pressure differences during cell manufacturing. This results in poor flatness consistency within the cells, significantly impacting module safety.

[0065] The flatness of battery cells is affected by factors such as the thickness of the incoming aluminum casing, temperature, and the pressure difference between the inside and outside of the cell. Currently, the flatness of the cells is generally controlled by secondary liquid injection and helium filling. This involves instantly increasing the internal gas pressure of the cell to inflate the casing and reduce its concavity. However, some products are prone to poor flatness consistency due to factors such as unreasonable helium filling parameters, large fluctuations in helium filling pressure, poor gas pressure consistency at different workstations, and long cell storage time. This is mainly manifested as some cells exceeding the lower limit of the flatness specification and cells being overly concave. Traditional cell flatness detection uses feeler gauge sampling, which cannot prevent the outflow of cells with unqualified flatness, significantly impacting the safety of the module. Moreover, cells with unqualified flatness require manual sorting, which is time-consuming and labor-intensive.

[0066] In addition, manual measurement has a certain measurement error, so the grading results are also biased. That is, in a batch of cells with small flatness, there may be some cells with large flatness, which will lead to glue overflow defects; in a batch of cells with large flatness, there may be some cells with small flatness, which will lead to poor glue coating area.

[0067] For example, after the battery cell is formed, the internal temperature reaches as high as 50°C. After the battery cell is sealed with sealing nails at this high temperature, due to the temperature difference between the inside and outside (ambient temperature 25°C), the battery cell gradually cools down, the internal air pressure decreases, and the external air pressure is greater than the internal air pressure. The aluminum shell is continuously under stress, causing the large surface and sides of the battery cell to become more concave. This results in the flatness of the battery cell continuing to become concave after it is placed in storage or stored, eventually exceeding the flatness specification. Therefore, reducing the temperature before sealing the battery cell can improve the flatness consistency of the battery cell and prevent the flatness of the battery cell from becoming concave over storage time. However, natural cooling is slow and inefficient.

[0068] This application provides a battery cell flatness adjustment device and method. The battery cell flatness adjustment device includes: a clamp and a controller; the clamp is used to clamp the battery cell, and the temperature control surface of the clamp is provided with multiple temperature control components, which are respectively connected to the controller. When the clamp clamps the battery cell, the temperature control surface is in contact with the cooling surface of the battery cell. The cooling surface includes multiple partitions, and the multiple partitions are respectively configured to correspond one-to-one with the multiple temperature control components; the controller is used to control the first temperature control component to cool the target partition according to the target cooling curve corresponding to the target partition during the clamping process of the battery cell, so as to reduce the flatness of the target partition. The target partition is any one of the multiple partitions, and the target cooling component is the cooling component corresponding to the target partition among the multiple cooling components.

[0069] In this embodiment, the temperature control surface of the clamp is equipped with multiple temperature control components, and the cooling surface of the battery cell includes multiple zones. Each zone corresponds to one of the multiple temperature control components. During the clamping process, the temperature control surface of the clamp contacts the cooling surface of the battery cell. The controller can control the multiple temperature control components to cool each zone according to its corresponding cooling curve. This reduces the battery cell temperature before sealing, decreases the internal and external temperature difference after sealing, reduces the internal and external pressure difference, and minimizes surface concavity, thereby improving the flatness of the battery cell. Furthermore, different areas on the cooling surface have different flatness requirements, necessitating different adjustments. By assigning multiple temperature control components to each zone, each zone can be independently and precisely temperature-controlled to meet the differentiated needs of different zones, thus improving the flatness of the battery cell more accurately.

[0070] Furthermore, it can reduce the number of cells with unacceptable flatness, improve cell safety, and save on manual sorting workload, saving time and effort. Moreover, it reduces the probability of individual cells with large flatness within a batch of cells with small flatness, and the probability of individual cells with small flatness within a batch of cells with large flatness, thereby reducing the occurrence of adhesive overflow defects and poor adhesive coating area.

[0071] In some embodiments of this application, the battery cell can be of any chemical type, such as a lithium-ion battery cell, a nickel-based battery cell, a sodium-based battery cell, a lead-acid battery cell, etc. Among them, lithium-ion battery cells include, but are not limited to, lithium cobalt oxide battery cells, lithium manganese oxide battery cells, lithium nickel oxide battery cells, lithium iron phosphate battery cells, etc.

[0072] In some embodiments of this application, the battery cell can be a battery cell of any shape and structure, such as a cylindrical battery cell, a flat battery cell, a pouch battery cell, a square battery cell, etc.

[0073] The battery cell flatness adjustment device and method provided in some embodiments of this application can be used between the battery cell formation process and the sealing process.

[0074] First, combined Figure 1 The cell flatness adjustment device provided in the embodiments of this application will be described in detail.

[0075] Figure 1 This illustration shows one of the structural schematic diagrams of a cell flatness adjustment device according to an embodiment of this application. Figure 1 As shown, the cell flatness adjustment device 100 may include a clamp 110 and a controller 120.

[0076] The clamp 110 can be used to hold the battery cell. The battery cell can be a battery cell that has completed formation but has not yet been sealed. The clamp 110 can be used to move the formed battery cell from the formation station to the sealing station.

[0077] The temperature control surface of the clamp 110 may be provided with multiple temperature control components 111, and the multiple temperature control components 111 may be connected to the controller 120 respectively. The temperature control surface may be a surface used to cool the battery cell. The temperature control components 111 may be used to cool the battery cell. For example, the temperature control components 111 may be a water cooling device or an air cooling device.

[0078] For example, the multiple temperature control components 111 can be arranged in a rectangular array of 1*1, 2*2, or 3*3. The arrangement of the multiple temperature control components 111 can be determined according to the pattern of cell depression.

[0079] When the battery cell is held by the clamp 110, the temperature control surface can contact the cooling surface of the battery cell. The cooling surface can be the surface of the battery cell to be cooled. The cooling surface can include multiple sections, and the multiple sections can be configured one-to-one with multiple temperature control components 111. For example, the cooling surface can be the large surface of the battery cell and / or the side surface of the battery cell.

[0080] The controller 120 can be used to control the first temperature control component to cool the target partition according to the target cooling curve corresponding to the target partition during the process of clamping the battery cell, so as to reduce the flatness of the target partition. The target partition can be any one of multiple partitions, and the target cooling component can be the cooling component 111 corresponding to the target partition among multiple cooling components 111.

[0081] The cooling component 111 can cool the battery cell during the process of the fixture 110 moving the formed battery cell from the forming station to the sealing station.

[0082] Flatness can be defined as the height difference between the most convex and the most concave points on a cooling surface. The smaller the flatness, the flatter the cooling surface.

[0083] The cooling curve can be a cooling trajectory for cooling a corresponding zone. Specifically, the cooling curve can be a curve of temperature changing over time. The controller 120 can control the temperature control component 111 to cool the corresponding zone to the temperature corresponding to that time at any time according to the cooling curve. Different zones can correspond to different cooling curves, and the target zone corresponds to the target cooling curve.

[0084] In this embodiment, the temperature control surface of the clamp 110 is provided with multiple temperature control components 111, and the cooling surface of the battery cell includes multiple zones. Each zone corresponds to one of the multiple temperature control components 111. During the clamping process of the battery cell, the temperature control surface of the clamp 110 contacts the cooling surface of the battery cell. The controller 120 can control the multiple temperature control components 111 to cool each zone according to the corresponding cooling curve. This reduces the battery cell temperature before sealing, reduces the internal and external temperature difference after sealing, reduces the internal and external pressure difference, and decreases the degree of surface concavity, thereby improving the flatness of the battery cell. Furthermore, different areas on the cooling surface have different flatness, requiring different adjustments. By setting multiple temperature control components 111 corresponding to multiple zones, each zone can be independently and precisely temperature-controlled to adapt to the differentiated needs of different zones, thus more accurately improving the flatness of the battery cell.

[0085] In some embodiments, the cell flatness adjustment device 100 may further include: a plurality of rangefinders. The plurality of rangefinders may be connected to the controller 120 respectively. The plurality of rangefinders may be configured one-to-one with a plurality of partitions.

[0086] The target rangefinder can be used to detect the height of the target zone and send the height to the controller 120. The target rangefinder can be the rangefinder corresponding to the target zone among multiple rangefinders.

[0087] The controller 120 can be used to determine the target flatness error of the target partition based on the height; and to determine the target cooling curve of the target partition based on the target flatness error.

[0088] Rangefinders can be non-contact rangefinders, such as laser rangefinders and ultrasonic rangefinders.

[0089] Specifically, before the battery cell formation is completed and before it is mounted on the fixture 110, the height of the target partition can be scanned in real time using a target rangefinder and fed back to the controller 120. The controller 120 can then calculate the flatness of the target partition in real time based on the height and further determine the target flatness error. The flatness error can be the error between the measured plane and the reference plane. Different flatness errors can correspond to different cooling curves. The mapping relationship between different flatness errors and different cooling curves can be preset, and then the target cooling curve corresponding to the target flatness error can be determined based on this mapping relationship, serving as the target cooling curve for the target partition.

[0090] For example, such as Figure 2 As shown, the rangefinder may include a high-voltage circuit 131, a field-programmable gate array (FPGA) 132, a time-to-digital converter (TDC) 133, a transmitting circuit 134, a receiving circuit 135, and optical elements 136. The transmitting circuit 134 may include a laser driver 1341 and a pulsed laser diode 1342.

[0091] A laser rangefinder emits a pulsed laser beam. When the laser beam strikes a target object, a portion of the laser beam is reflected back. The laser rangefinder calculates the distance between the target object's surface and the laser rangefinder by measuring the time difference (TOF) between the emitted pulse and the received reflected pulse, and using the speed of light (c). The formula is: Distance = Speed ​​of light × Time difference / 2. An ultrasonic rangefinder emits high-frequency sound waves (typically around 40kHz). When the sound waves encounter a target object, a portion of the sound waves is reflected back. The ultrasonic rangefinder calculates the distance between the target object's surface and the ultrasonic rangefinder by measuring the time difference (TOF) between the emitted and received sound waves, and using the speed of sound (approximately 340m / s in air). The formula is: Distance = Speed ​​of sound × Time difference / 2. The method for calculating the height of the target partition in this embodiment is the same as the method for calculating the distance described above.

[0092] In this way, by setting up multiple rangefinders that correspond one-to-one with multiple zones, the height of each zone can be accurately determined, laying the foundation for independent zone temperature control.

[0093] In some embodiments, such as Figure 3 As shown, the temperature control surface is also equipped with multiple temperature sensors 112. Each of the multiple temperature sensors 112 can be connected to the controller 120. Each of the multiple temperature sensors 112 can be configured to correspond one-to-one with multiple zones.

[0094] With the battery cell held in place by the clamp 110, the temperature control surface is in contact with the cooling surface of the battery cell, so multiple temperature sensors 112 can contact the cooling surface of the battery cell to perform temperature detection. The temperature sensors 112 can be high-precision temperature sensors, such as PT100 platinum resistance thermometers.

[0095] The target temperature sensor can be used to detect the current temperature of the target partition and send the current temperature to the controller 120. The target temperature sensor can be the temperature sensor 112 corresponding to the target partition among multiple temperature sensors 112.

[0096] Each temperature sensor 112 can sense the temperature of its surroundings, i.e., the current temperature, and feed it back to the controller 120.

[0097] Controller 120 can be used to determine the target cooling curve for the target zone based on the current temperature.

[0098] In this way, by setting multiple temperature sensors 112 to correspond one-to-one with multiple zones, the current temperature of each zone can be accurately detected, laying the foundation for independent zone temperature control.

[0099] In some embodiments, the multiple partitions may include at least two of the following: the tab side region of the battery cell, the winding and closing region, the stacked and misaligned region, and the central region.

[0100] The tab side area, winding and closing area, stacking misalignment area, and central area of ​​the battery cell are usually prone to concavity. Therefore, these areas can be set as partitions and cooled to effectively improve the flatness of the battery cell.

[0101] In some embodiments, such as Figure 4 As shown, the temperature control component 111 may include a thermoelectric cooler (TEC), and the cold end 41 of the TEC may be disposed on the temperature control surface.

[0102] A TEC (Cooling Thermoelectric Temperature Coefficient) can consist of a cold end and a hot end; the cold end absorbs heat, and the hot end releases heat. The cooling principle of a TEC can be described as follows: Figure 5As shown, when current flows through a thermocouple formed by a negative (N)-type semiconductor and a positive (P)-type semiconductor, heat transfer occurs between the two ends, creating a temperature difference that forms a cold junction and a hot junction. Connecting dozens or even hundreds of such PN junction pairs in parallel via a ceramic substrate constitutes a TEC module. When energized, the cold junction absorbs heat on one side, while the hot junction releases heat on the other. By changing the direction of the current, the hot and cold junctions can be switched, enabling bidirectional temperature control of the battery cell. Therefore, it can be used in applications requiring cooling as well as heating or bidirectional temperature control. The heating / cooling rate can be controlled by changing the current magnitude. The temperature of the cold junction can be controlled by the current from an external power supply, and the temperature can also be displayed in real time on an external display screen. The advantages of TEC are: small space requirement, easy installation and long life, high safety and reliability, can be integrated into the fixture and make close contact with the battery cell for cooling; precise temperature control can be achieved by adjusting the magnitude and direction of the current, with an accuracy of ±0.1°C; no mechanical moving parts, low thermal inertia, and fast heating and cooling speeds; TEC modules can be made relatively small, making it easy to integrate multiple modules into the fixture to achieve independent zone temperature control.

[0103] For example, the fixture may be hollow, and the TEC may be embedded in the fixture such that the cold end 41 of the TEC is located on the temperature control surface of the fixture 110.

[0104] Thus, the TEC is small in size, making it easy to integrate multiple TECs on the fixture 110 to achieve independent zone temperature control. In addition, the TEC has high temperature control accuracy, which makes it easy to accurately control the cooling of the battery cell.

[0105] In some embodiments, such as Figure 4 As shown, the hot end 42 of the TEC can be provided with a heat dissipation layer 43.

[0106] The heat dissipation layer 43 can be used to efficiently dissipate the heat accumulated on the hot end 42. The heat dissipation capacity of the heat dissipation layer 43 can be greater than the maximum cooling power of the hot end 42.

[0107] For example, the heat dissipation layer 43 can be a water-cooled plate. A water-cooled plate is attached to the hot end 42, and a high-speed flowing coolant inside the water-cooled plate quickly removes heat.

[0108] For example, the heat dissipation layer 43 can also be a cooling fan.

[0109] Thus, by setting a heat dissipation layer 43 on the hot end 42 of the TEC, the heat accumulated on the hot end 42 can be dissipated efficiently to avoid overheating and safety hazards.

[0110] In some embodiments, such as Figure 4As shown, a first thermally conductive layer 441 may be disposed between the hot end 42 of the TEC and the heat dissipation layer 43. The first thermally conductive layer 441 may be made of a highly thermally conductive material.

[0111] Thus, by placing a first thermally conductive layer 441 between the hot end 42 of the TEC and the heat dissipation layer 43, thermal resistance can be reduced, heat conduction can be accelerated, and heat dissipation efficiency can be improved.

[0112] In some embodiments, the first thermally conductive layer 441 may be thermally conductive silicone grease or indium foil.

[0113] Thus, thermal grease is inexpensive, and choosing thermal grease as the first thermal conductive layer can reduce costs; indium foil has low thermal resistance, and choosing indium foil as the first thermal conductive layer can improve thermal conductivity.

[0114] In some embodiments, a second thermally conductive layer 442 may be provided between the cold end 41 of the TEC and the cooling surface. The second thermally conductive layer 442 may be a material with high thermal conductivity.

[0115] Thus, by placing a second heat-conducting layer 442 between the cold end 41 of the TEC and the cooling surface, thermal resistance can be reduced, heat conduction can be accelerated, and cooling efficiency can be improved.

[0116] In some embodiments, the second thermally conductive layer may be thermally conductive silicone grease or indium foil.

[0117] Thus, thermal grease is inexpensive, and choosing it as the first thermal conductive layer can reduce costs. Moreover, thermal grease is insulating, which can reduce the probability of short circuits caused by conductivity between the charged battery cell and the clamp. Indium foil has low thermal resistance, and choosing it as the first thermal conductive layer can improve thermal conductivity.

[0118] In some embodiments, an insulating layer may be provided between the cold end 41 of the TEC and the cooling surface.

[0119] To ensure that the insulation layer does not block heat transfer between the cold end 41 of the TEC and the cooling surface, the insulation layer may have thermal conductivity. For example, the insulation layer may be thermally conductive silicone, an aluminum nitride ceramic sheet, or an alumina ceramic sheet.

[0120] Thus, by setting an insulating layer between the cold end and the cooling surface, the probability of a short circuit caused by conductivity between the charged battery cell and the clamp can be reduced.

[0121] In some examples, multiple rangefinders scan the height of each partition in real time to determine the flatness error of each partition. A 0.1mm pit is found in partition A, while the flatness of partition B is acceptable. The control algorithm, based on preset rules (such as "prioritizing cooling of pitted areas"), calculates that the cooling power of the TEC corresponding to partition A needs to be increased by X%, and the cooling power of the TEC corresponding to partition B needs to be reduced or stopped. Control commands are sent to the drive channel corresponding to partition A to increase the current, and to the drive channel corresponding to partition B to decrease / stop the current. The temperature of partition A drops rapidly, the material shrinks, and the flatness is improved. Multiple rangefinders continuously monitor and identify the flatness of each partition, and control the TEC to provide priority and enhanced cooling to the identified pitted areas at different rates until the flatness meets the standard. The control system adjusts the temperature of each partition to a balanced state, and the flatness of the cell cooling surface meets the standard.

[0122] In some examples, the temperature control surface of the fixture 110 can be designed as multiple independently temperature-controlled micro-blocks, each block embedding a TEC (Thermal Design Temperature Regulator), and each TEC connected to an independent drive channel. Furthermore, a high-precision temperature sensor (such as a PT100 platinum resistance thermometer) can be integrated into each block to provide real-time feedback on the temperature of the corresponding cell cooling surface, achieving differentiated cooling for each zone. Specifically, multiple independently controlled TECs can be integrated into the temperature control surface of the fixture 110. During the cooling process, different cooling intensities are applied to different zones to compensate for uneven cooling contraction caused by structural inhomogeneities (such as the tab side, winding seam, lamination misalignment area, and easily dented central area). Stronger cooling power is applied to the TECs in easily dented areas, ensuring that these areas cool synchronously with other areas, preventing new stress warping due to asynchronous cooling rates. This gradient differentiated cooling can balance the shrinkage stress difference caused by structural inhomogeneities, allowing the entire cooling surface to resist atmospheric pressure uniformly and stably before sealing, avoiding localized dents.

[0123] Below, in conjunction with Figure 6 The method for adjusting the flatness of the battery cell provided in the embodiments of this application will be described in detail.

[0124] Figure 6 This paper illustrates one of the flowcharts of a cell flatness adjustment method according to an embodiment of this application. It should be noted that the cell flatness adjustment method can be applied to the cell flatness adjustment device shown in any of the above embodiments.

[0125] like Figure 6 As shown, the cell flatness adjustment method may include the following steps: S610, obtain the target cooling curve corresponding to the target zone of the battery cell; S620 controls the target temperature control component to cool the target zone according to the target cooling curve during the clamping process of the battery cell, so as to reduce the flatness of the target zone.

[0126] The cooling surface of the battery cell can include multiple zones, and the target zone can be any one of these zones. The temperature control surface of the clamp can be equipped with multiple temperature control components, which can contact the cooling surface when the clamp holds the battery cell. Each of the multiple zones can be assigned a corresponding temperature control component. The target cooling component can be the one that corresponds to the target zone among the multiple cooling components.

[0127] For details on the specific process, please refer to the above embodiments, which will not be repeated here.

[0128] In this embodiment, the temperature control surface of the clamp is equipped with multiple temperature control components, and the cooling surface of the battery cell includes multiple zones. Each zone corresponds to one of the multiple temperature control components. During the clamping process, the temperature control surface of the clamp contacts the cooling surface of the battery cell. The controller can control the multiple temperature control components to cool each zone according to its corresponding cooling curve. This reduces the battery cell temperature before sealing, decreases the internal and external temperature difference after sealing, reduces the internal and external pressure difference, and minimizes surface concavity, thereby improving the flatness of the battery cell. Furthermore, different areas on the cooling surface have different flatness requirements, necessitating different adjustments. By assigning multiple temperature control components to each zone, each zone can be independently and precisely temperature-controlled to meet the differentiated needs of different zones, thus improving the flatness of the battery cell more accurately.

[0129] In some embodiments, S610 may include: Obtain the first mapping relationship between the partition and the cooling curve; Based on the first mapping relationship, the target cooling curve corresponding to the target partition is determined.

[0130] The first mapping relationship can include multiple partitions and their corresponding cooling curves. Specifically, multiple cooling curves corresponding to each partition can be pre-set to obtain the first mapping relationship. When cooling of a target partition is required, the target cooling curve corresponding to the target partition can be determined based on this first mapping relationship. The cooling curves corresponding to multiple partitions can be obtained through experimental testing.

[0131] In this way, the cooling curve corresponding to any partition can be quickly determined based on the first mapping relationship between the partition and the cooling curve, which facilitates the rapid cooling of each partition.

[0132] In some embodiments, S610 may include: Obtain the second mapping relationship between flatness error and cooling curve, and the target flatness error of the target partition; Based on the second mapping relationship, the target cooling curve corresponding to the target flatness error is determined.

[0133] Here, flatness error can be defined as the height error between the measured plane and the reference plane. Different flatness errors require different degrees of flatness improvement, therefore, different cooling curves can be determined for different flatness errors.

[0134] Specifically, multiple cooling curves corresponding to different flatness errors can be pre-set to obtain a second mapping relationship. When cooling of a target area is required, the target flatness error of the target area can be obtained first. Then, based on the second mapping relationship, the target cooling curve corresponding to the target flatness error can be determined as the target cooling curve for the target area. The cooling curves corresponding to multiple flatness errors can be obtained through experimental testing.

[0135] In this way, by obtaining the flatness error and the second mapping relationship of each partition, the cooling curve corresponding to each partition can be accurately determined based on the flatness error, thus facilitating precise cooling of each partition.

[0136] In some embodiments, S610 may include: Obtain the current temperature, target desired temperature, and preset duration of the target partition; Based on the current temperature, the target desired temperature, and the preset duration, a target cooling curve is generated.

[0137] The preset duration can be defined as the allowable time for the target zone to cool from its current temperature to the desired target temperature. The preset duration can be less than or equal to the time the fixture holds the battery cell. Since cooling of the battery cell needs to be completed during its movement from the formation station to the sealing station, the preset duration can be determined based on the time required for the fixture to move the formed battery cell from the formation station to the sealing station. The desired target temperature can be the temperature that the target zone is expected to reach after the preset duration.

[0138] For example, the current temperature of the target zone is 45°C. The target zone needs to reach the target desired temperature of 35°C before sealing. It takes 15 minutes for the fixture to move the formed cell from the formation station to the sealing station. Therefore, the preset time can be 15 minutes. That is to say, the temperature of the target zone needs to be reduced from 45°C to 35°C within 15 minutes. The target cooling curve can be a curve in which the temperature drops from 45°C to 35°C at a constant rate within 15 minutes.

[0139] In this way, the temperature of the target zone can be reduced from the current temperature to the desired temperature during the transfer of the battery cell using a clamp, which improves the flatness of the battery cell without spending extra time.

[0140] In some embodiments, obtaining the target desired temperature for the target partition may include: Obtain the third mapping relationship between the partition and the desired temperature; Based on the third mapping relationship, the target expected temperature corresponding to the target partition is determined.

[0141] The third mapping relationship can include multiple partitions and their corresponding desired temperatures. Specifically, the desired temperatures for multiple partitions can be preset to obtain the third mapping relationship. When it is necessary to cool a target partition, the target desired temperature for that partition can be determined based on this third mapping relationship. The desired temperatures for multiple partitions can be obtained through experimental testing.

[0142] In this way, the desired temperature of any partition can be quickly determined based on the third mapping relationship between the partition and the desired temperature, which makes it easier to cool down each partition quickly.

[0143] In some embodiments, obtaining the target desired temperature for the target partition may include: Obtain the target flatness error and current temperature of the target partition; Determine the target temperature change of the target zone based on the target flatness error; The target desired temperature is determined based on the current temperature and the change in the target temperature.

[0144] Specifically, a mapping relationship between flatness error and temperature change can be pre-defined. This mapping relationship can include multiple flatness errors and their corresponding temperature changes. In this mapping relationship, the temperature change corresponding to each flatness error can be the temperature change required to correct that flatness error.

[0145] For example, a temperature compensation map can be generated based on the location and flatness error of each partition. Specifically, the temperature change of each partition can be determined based on the flatness error of each partition, and then the temperature change is marked on the location of each partition to obtain the temperature compensation map. This temperature compensation map can clearly show the required temperature change of each partition.

[0146] When cooling is required for a target area, this mapping relationship can be used to determine the target temperature change corresponding to the target flatness error of the target area. This target temperature change can be the amount of temperature change required to correct the target flatness error.

[0147] The target desired temperature can be the difference between the current temperature of the target zone and the change in the target temperature.

[0148] In this way, the required temperature change for a partition can be accurately determined based on the partition's flatness error, and the target desired temperature for that partition can be accurately determined based on its current temperature and the temperature change.

[0149] In some embodiments, since the degree of indentation at the same location on the cooling surface of different cells is usually similar, the required flatness improvement for the same zone of different cells is roughly the same. Initially, the target desired temperature can be determined using the aforementioned scheme of determining the target temperature change based on the target flatness error, and then determining the target desired temperature. Later, based on previously accumulated data and experience, the target desired temperature for different zones can be directly determined. For example, for zones prone to indentation or with poor flatness, such as the tab side region, winding and closing region, the stacked misalignment region, and the center region of the cell, lower target desired temperatures can be set for these zones. For example, the target desired temperature for the zone corresponding to the center region can be 25°C, and the target desired temperature for the zone corresponding to the edge region can be 35°C. Zones with lower temperatures experience greater shrinkage, causing the easily indented center region to shrink more than the surrounding edge regions, thus actively "flattening" it.

[0150] Furthermore, by setting a higher cooling rate for the corresponding zones of the easily concave central area, support can be established in the easily concave central area in advance. This allows the easily concave central area to cool first and rapidly transform from a "soft" to a "rigid" state through the glass transition temperature (Tg) of the adhesive, forming a "skeleton." While the central area has solidified and hardened, the edge areas remain in a relatively soft and malleable state. This stress releases the edge areas, and as they cool and shrink, the shrinkage stress acts on the already solidified and robust central area. Since the central area can no longer be easily pulled, the shrinkage force at the edges is used more for self-compactment rather than causing the entire center to collapse.

[0151] In some embodiments, generating a target cooling curve based on the current temperature, the target desired temperature, and a preset duration may include: Obtain the fourth mapping relationship between flatness error and cooling curve type, and the target flatness error of the target partition; Based on the fourth mapping relationship, the type of target cooling curve corresponding to the target flatness error is determined; Based on the current temperature, target desired temperature, preset duration, and target cooling curve type, a target cooling curve is generated.

[0152] The fourth mapping relationship can include multiple flatness errors and their corresponding cooling curve types. Specifically, multiple cooling curve types corresponding to different flatness errors can be preset to obtain the fourth mapping relationship. When cooling is required for a target area, the target cooling curve type corresponding to the target flatness error of the target area can be determined based on this fourth mapping relationship.

[0153] For example, the cooling curve type may include, but is not limited to, uniform, fast at first and slow later, stepped, etc.

[0154] For example, for partitions with a flatness error ≤ ±0.2mm, a slow and uniform cooling curve can be used to reduce the temperature to the target desired temperature of 35℃, i.e., a cooling rate of about 1℃ / min; for partitions with a flatness error of ±0.2mm < ±0.5mm, a cooling curve that is fast at first and then slow can be used to reduce the temperature to the target desired temperature of 30℃; for partitions with a flatness error > ±0.5mm, a stepped (multi-step cooling) cooling curve can be used to reduce the temperature to the target desired temperature of 25℃, thereby achieving dynamic temperature control of the partitions.

[0155] Of course, other cooling curve types can also be included, such as the fast-slow-fast-fast type, which rapidly cools down to a critical temperature point (such as near the glass transition temperature Tg) in the high-temperature region, then slowly cools down to fully release stress, and finally rapidly cools down to room temperature to improve efficiency.

[0156] In this way, different cooling curve types can be used for zones with different flatness errors to achieve more precise dynamic temperature control of zones.

[0157] In some embodiments, during the clamping of the battery cell by the fixture, controlling the target temperature control component to cool the target zone according to the target cooling curve to reduce the flatness of the target zone may include: The electrical parameters of the target temperature control component are determined based on the target cooling curve. During the clamping process of the battery cell, the target temperature control component is controlled based on electrical parameters to cool the target area in order to reduce the flatness of the target area.

[0158] Electrical parameters can control the temperature of the target temperature control component. The target cooling curve can be a curve showing the temperature changing over time. At any given time, the temperature corresponding to that time can be determined based on the target cooling curve. Then, based on that temperature, electrical parameters can be determined and output to the target temperature control component at that time. This controls the target temperature control component to change its own temperature, thereby cooling the target zone and reducing the flatness of the target zone.

[0159] Specifically, the mapping relationship between temperature and electrical parameters can be pre-calibrated, and the electrical parameters corresponding to each temperature on the target cooling curve can be determined based on the mapping relationship. The electrical parameter curve of electrical parameter change over time can then be obtained, and the target temperature control component can be controlled based on the electrical parameter curve.

[0160] In this way, by determining the electrical parameters of the temperature control components for each zone based on the cooling curves of each zone, the cooling rate of each zone can be adjusted, thereby achieving precise zone temperature control.

[0161] In some embodiments, electrical parameters may include current or power.

[0162] Specifically, the mapping relationship between temperature and current can be pre-calibrated. Based on this mapping relationship, the current curve corresponding to the target cooling curve can be determined. Then, current is output to the target temperature control component according to the current curve to control the target temperature control component to change its own temperature and cool the target zone.

[0163] Alternatively, the mapping relationship between temperature and power can be pre-calibrated. Based on this mapping relationship, the power curve corresponding to the target cooling curve can be determined. Then, the power of the target temperature control component can be controlled according to the power curve to change the temperature of the target temperature control component and cool down the target zone.

[0164] In this way, by controlling the current or power of the temperature control components in each zone, the cooling rate of each zone can be controlled simply and accurately.

[0165] In some embodiments, after controlling the target temperature control component to cool the target zone according to the target cooling curve to reduce the flatness of the target zone, the method may further include: Obtain the target flatness of the target partition; Based on the target flatness being less than or equal to a preset threshold, the sealing equipment is controlled to seal the battery cell; Based on the target flatness being greater than a preset threshold, the sorting equipment is controlled to move the battery cells to the target area.

[0166] After improving the flatness of the target partition through the above embodiments, the flatness of the target partition can be checked again to see if it meets the standard. Specifically, if the target flatness is less than or equal to a preset threshold, it indicates that the flatness of the target partition meets the standard; if the target flatness is greater than the preset threshold, it indicates that the flatness of the target partition does not meet the standard.

[0167] Then, the flatness of the battery cell can be determined based on whether the flatness of multiple partitions meets the standard. For example, if the flatness of multiple partitions all meets the standard, the flatness of the battery cell is determined to be compliant; if the flatness of any one of the multiple partitions does not meet the standard, the flatness of the battery cell is determined to be non-compliant.

[0168] If the flatness of the battery cell meets the standard, subsequent production processes can proceed, and the sealing equipment can be used to seal the cell. If the flatness of the battery cell does not meet the standard, it needs to be further improved. For example, the flatness can be improved by secondary electrolyte injection or helium filling. Then, the flatness can be checked again to see if it meets the standard. If it does, it can be sealed. If it does not meet the standard, the flatness can be improved by other methods, or the battery cell can be discarded.

[0169] Sealing equipment can be used to seal battery cells with sealing nails. Sorting equipment is used to transfer battery cells to secondary electrolyte filling and helium filling stations.

[0170] For example, after the battery cell reaches the sealing station and is unloaded from the fixture, the flatness of the battery cell can be tested again to see if it meets the standard. If it does, it is sealed. If it does not meet the standard, the flatness of the battery cell can be further improved by secondary liquid injection or helium filling.

[0171] In this way, cells that meet or do not meet the flatness standard can be handled automatically and properly, improving the level of automation in cell production.

[0172] In some examples, such as Figure 7 As shown, the zoned temperature control system 700 may include a temperature control panel 701 connected to multiple independently controlled TECs. During the cooling phase, independent power or current can be applied to different TECs corresponding to different zones. Each zone is equipped with a temperature detection module 702, which may include a temperature sensor, a comparison module, and a feedback module. The module compares the current temperature with the target desired temperature in real time and feeds the feedback to the central processing unit 703, dynamically adjusting the amount of power or current applied to each zone to regulate the cooling rate, thereby enabling uniform cooling of the cell's cooling surface.

[0173] The control unit can run an independent proportional-integral-derivative (PID) control algorithm for each zone. The algorithm calculates the magnitude and direction of the required output current based on the desired temperature and the current temperature of that zone, thereby achieving zoned temperature control.

[0174] like Figure 8As shown, this embodiment of the application integrates the TEC array fixture 810, the heat dissipation system 820, the multi-channel power driver 830, the sensor network 840, the flatness detection system 850, and the control unit 860 into a cell flatness adjustment system 800. This enables the fixture to perform zoned dynamic programmed temperature control of the cell, thereby improving the flatness consistency of the cell. The control unit 860 can perform zoned temperature control using an intelligent control algorithm. The control unit 860 can be a central processing unit (CPU) or a programmable logic controller (PLC).

[0175] In a specific example, the temperature of the battery cell after exiting the formation process is greater than 45°C, and the time for transferring the battery cell from the formation station to the sealing station is generally 15 minutes. During the transfer of the battery cell using traditional fixtures, the temperature drop curve of the battery cell can be shown as follows: Figure 9 As shown, by Figure 9 It can be seen that the cell temperature is still greater than 40℃ after 15 minutes, and there is a large temperature difference between the inside and outside of the cell. The pressure difference caused by the temperature difference will cause the flatness of the large surface and side of the cell to become concave, exceeding the flatness specification.

[0176] During the transfer of battery cells using the cooling fixture provided in this application embodiment, the cooling curve of the battery cell can be as follows: Figure 10 As shown, by Figure 10 It can be seen that the cell temperature drops to 35℃ after 15 minutes (the cooling rate can be increased by increasing the power or current of the TEC, so that the cell has a lower temperature before sealing). Welding the sealing nails of the cell at this temperature reduces the temperature difference and pressure difference between the inside and outside of the cell, and improves the flatness consistency.

[0177] Specifically, after the cells are formed, 64 cells are verified using both traditional clamps and cooling clamps provided in the embodiments of this application. Normal flow drawing is performed, and the flatness of the cells using the two types of clamps is measured at the sealing nail.

[0178] As shown in Table 1, compared with traditional clamps, cooling clamps can reduce the cell temperature by 6°C to 7°C, thereby improving the average flatness of the cell after sealing with sealing nails and improving the uniformity of cell flatness.

[0179] Table 1 - Test Results

[0180] This application embodiment utilizes a programmed cooling curve, avoiding reliance on slow natural cooling or forced cooling. The cooling rate and gradient are actively controlled by a TEC (Thermal Design Temperature) according to a preset program. Excessive cooling can cause the adhesive to cure too quickly, preventing sufficient release of internal stress and leading to springback and warping. Therefore, a rapid-then-slow or stepped cooling curve can be used. For example, rapid cooling to a critical temperature point (such as near the glass transition temperature Tg) in the high-temperature zone, followed by slow cooling to fully release stress, and finally rapid cooling to room temperature to improve efficiency. In the step of active cooling according to a preset cooling curve, the cooling curve can include at least two stages with different cooling rates. For example, a rapid-then-slow cooling curve can be as follows: Figure 10 As shown.

[0181] In this embodiment, by integrating multiple TECs onto the fixture, the battery cell is cooled while it is being drawn normally. Depending on the actual drawing situation, different fixtures can be modified between the formation, secondary injection, and sealing nail welding stages to meet the cooling requirements. It can also be used in other scenarios where battery cell cooling is required.

[0182] This application embodiment achieves independent and precise temperature control and localized differentiated cooling by using a TEC array and temperature sensors; it also achieves dynamic programmed control with real-time feedback by using temperature sensors and rangefinders, combining the rapid response capability of the TEC with sensor feedback to form a closed-loop control.

[0183] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the claims.

[0184] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0185] One or more of the components, steps, features, and / or functions disclosed in this application may be rearranged and / or combined into a single component, step, feature, or function, or distributed among several components, steps, or functions. Those skilled in the art may also add additional elements, components, steps, and / or functions without departing from the scope disclosed herein.

[0186] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell flatness adjustment device, characterized in that, include: Fixtures and controllers; The clamp is used to hold the battery cell. The temperature control surface of the clamp is provided with multiple temperature control components. The multiple temperature control components are respectively connected to the controller. When the clamp holds the battery cell, the temperature control surface contacts the cooling surface of the battery cell. The cooling surface includes multiple partitions, and the multiple partitions are configured one-to-one with the multiple temperature control components. The controller is used to control a first temperature control component to cool the target partition according to the target cooling curve corresponding to the target partition during the process of the clamp holding the battery cell, so as to reduce the flatness of the target partition. The target partition is any one of the plurality of partitions, and the target cooling component is the cooling component corresponding to the target partition among the plurality of cooling components.

2. The cell flatness adjustment device according to claim 1, characterized in that, The cell flatness adjustment device further includes: multiple rangefinders, each connected to the controller, and the multiple rangefinders are configured to correspond one-to-one with the multiple partitions; The target rangefinder is used to detect the height of the target partition and send the height to the controller. The target rangefinder is the rangefinder corresponding to the target partition among the plurality of rangefinders. The controller is used to determine the target flatness error of the target partition based on the height; and to determine the target cooling curve of the target partition based on the target flatness error.

3. The cell flatness adjustment device according to claim 1 or 2, characterized in that, The temperature control surface is also provided with multiple temperature sensors, which are respectively connected to the controller, and the multiple temperature sensors are configured one-to-one with the multiple partitions; The target temperature sensor is used to detect the current temperature of the target partition and send the current temperature to the controller. The target temperature sensor is the temperature sensor corresponding to the target partition among the plurality of temperature sensors. The controller is used to determine the target cooling curve of the target zone based on the current temperature.

4. The cell flatness adjustment device according to claim 1, characterized in that, The plurality of zones include at least two of the following: the tab side region, the winding and closing region, the stacked and misaligned region, and the central region of the battery cell.

5. The cell flatness adjustment device according to claim 1, characterized in that, The temperature control component includes a semiconductor cooler, and the cold end of the semiconductor cooler is disposed on the temperature control surface.

6. The cell flatness adjustment device according to claim 5, characterized in that, The hot end of the semiconductor cooler is provided with a heat dissipation layer.

7. The cell flatness adjustment device according to claim 6, characterized in that, A first thermally conductive layer is provided between the hot end of the semiconductor cooler and the heat dissipation layer.

8. The cell flatness adjustment device according to claim 7, characterized in that, The first thermal conductive layer is thermal grease or indium foil.

9. The cell flatness adjustment device according to claim 5, characterized in that, A second heat-conducting layer is provided between the cold end of the semiconductor cooler and the cooling surface.

10. The cell flatness adjustment device according to claim 9, characterized in that, The second thermally conductive layer is thermally conductive silicone grease or indium foil.

11. The cell flatness adjustment device according to claim 5, characterized in that, An insulating layer is provided between the cold end of the semiconductor cooler and the cooling surface.

12. A method for adjusting the flatness of a battery cell, characterized in that, include: Obtain the target cooling curve corresponding to the target partition of the battery cell. The cooling surface of the battery cell includes multiple partitions, and the target partition is any one of the multiple partitions. During the process of clamping the battery cell, the target temperature control component is controlled to cool the target partition according to the target cooling curve in order to reduce the flatness of the target partition; The clamp has multiple temperature control components on its temperature control surface. When the clamp holds the battery cell, the temperature control surface contacts the cooling surface. The multiple partitions are configured one-to-one with the multiple temperature control components. The target cooling component is the cooling component that corresponds to the target partition among the multiple cooling components.

13. The method according to claim 12, characterized in that, The acquisition of the target cooling curve corresponding to the target zone of the battery cell includes: Obtain the first mapping relationship between the partition and the cooling curve; Based on the first mapping relationship, the target cooling curve corresponding to the target partition is determined.

14. The method according to claim 12, characterized in that, The acquisition of the target cooling curve corresponding to the target zone of the battery cell includes: Obtain the second mapping relationship between flatness error and cooling curve, and the target flatness error of the target partition; Based on the second mapping relationship, the target cooling curve corresponding to the target flatness error is determined.

15. The method according to claim 12, characterized in that, The acquisition of the target cooling curve corresponding to the target zone of the battery cell includes: The current temperature, target desired temperature, and preset duration of the target zone are obtained, wherein the preset duration is less than or equal to the duration for which the clamp holds the battery cell; The target cooling curve is generated based on the current temperature, the target desired temperature, and the preset duration.

16. The method according to claim 15, characterized in that, Obtaining the target desired temperature for the target partition includes: Obtain the third mapping relationship between the partition and the desired temperature; Based on the third mapping relationship, the target desired temperature corresponding to the target partition is determined.

17. The method according to claim 15, characterized in that, Obtaining the target desired temperature for the target partition includes: Obtain the target flatness error and current temperature of the target partition; The target temperature change of the target zone is determined based on the target flatness error. The target desired temperature is determined based on the current temperature and the change in the target temperature.

18. The method according to claim 15, characterized in that, The step of generating the target cooling curve based on the current temperature, the target desired temperature, and the preset duration includes: Obtain the fourth mapping relationship between flatness error and cooling curve type, and the target flatness error of the target partition; Based on the fourth mapping relationship, the target cooling curve type corresponding to the target flatness error is determined; The target cooling curve is generated based on the current temperature, the target desired temperature, the preset duration, and the target cooling curve type.

19. The method according to claim 12, characterized in that, During the process of clamping the battery cell with the fixture, controlling the target temperature control component to cool the target zone according to the target cooling curve to reduce the flatness of the target zone includes: The electrical parameters for controlling the target temperature control component are determined based on the target cooling curve. During the process of clamping the battery cell, the target temperature control component is controlled based on the electrical parameters to cool the target partition, thereby reducing the flatness of the target partition.

20. The method according to claim 19, characterized in that, The electrical parameters include current or power.

21. The method according to claim 12, characterized in that, After the target temperature control component cools the target zone according to the target cooling curve to reduce the flatness of the target zone, the method further includes: Obtain the target flatness of the target partition; Based on the target flatness being less than or equal to a preset threshold, the sealing device is controlled to seal the battery cell; Based on the target flatness being greater than the preset threshold, the sorting equipment is controlled to move the battery cell to the target area.

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