Battery cell cleaning apparatus and method for manufacturing battery cell using same

Abstract

The present invention provides a battery cell cleaning apparatus for improving electrolyte impregnation, and a method for preparing a battery cell using same, the battery cell cleaning apparatus comprising: a main body part configured such that at least one battery cell is immersed in a liquid medium accommodated in an internal space; and a vibration part attached to the main body part and configured to generate vibration and transmit the generated vibration to the liquid medium, wherein the vibration part is configured to apply the vibration toward both ends of the battery cell in the length direction through the liquid medium.

Description

Battery cell cleaning device and battery cell manufacturing method using the same

[0001] The present invention relates to a battery cell cleaning device and a method for manufacturing a battery cell using the same, and more specifically, to a battery cell cleaning device for improving electrolyte impregnation and a method for manufacturing a battery cell using the same. This application is a priority claim application for Korean Patent Application No. 10-2024-0193125 filed on December 20, 2024, and all contents disclosed in the specification and drawings of said application are incorporated by reference into this application.

[0002] Secondary batteries, which possess electrical characteristics such as high energy density and high applicability across product groups, are widely applied not only to portable devices but also to electric vehicles (EVs) or hybrid electric vehicles (HEVs) powered by electric sources. These secondary batteries are attracting attention as a new energy source for enhancing eco-friendliness and energy efficiency, not only for the primary advantage of drastically reducing the use of fossil fuels but also because they generate no by-products from energy use.

[0003] Currently, widely used types of secondary batteries include lithium-ion batteries, lithium-polymer batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-zinc batteries. The operating voltage of these unit secondary battery cells, or unit battery cells, is approximately 2.5V to 4.5V. Therefore, if a higher output voltage is required, multiple battery cells are connected in series to form a battery pack. Additionally, depending on the charge / discharge capacity required for the battery pack, multiple battery cells are connected in parallel to form a battery pack. Accordingly, the number of battery cells included in the battery pack can be varied depending on the required output voltage or charge / discharge capacity.

[0004] On the other hand, relying solely on vacuum and pressurization treatments after injecting the electrolyte from the top of the cylindrical battery cell may have limitations in completely impregnating the entire electrode assembly with the electrolyte. For example, the electrolyte impregnation rate may differ between the top and bottom of the electrode assembly. More specifically, there may be cases where residual electrolyte accumulates at the bottom of the cylindrical battery cell after injection, while the electrolyte is not properly impregnated at the top.

[0005] Furthermore, because the gaps between the positive plate, separator, and negative plate constituting the electrode assembly are formed very narrowly, the electrolyte injected through the upper opening of the battery can may remain only at the top of the battery can due to capillary action and may not be effectively delivered to the bottom of the battery can. Alternatively, during vacuum and pressurization processes, although the delivery of the electrolyte to the top or bottom of the battery can may be easy, the electrolyte may not reach the center of the electrode assembly, resulting in the existence of unimpregnated areas.

[0006] When such unimpregnated electrolyte regions exist, the movement of lithium ions is hindered, which can lead to a decrease in battery cell capacity compared to the design, increased battery cell resistance, voltage non-uniformity, and reduced safety due to lithium precipitation. Additionally, there is a problem in that vacuum and pressurization processes for electrolyte impregnation may require a considerable amount of time.

[0007] Therefore, research is needed on methods to improve electrolyte impregnation and simplify the process by reducing the unimpregnated area of ​​the electrolyte-injected battery cell.

[0008] Accordingly, the technical problem to be solved by the present invention is to provide a battery cell cleaning device for improving electrolyte impregnation and a method for manufacturing a battery cell using the same.

[0009] In addition, the invention provides a battery cell cleaning device capable of cleaning foreign substances from a battery can, and a method for manufacturing a battery cell using the same.

[0010] In addition, the present invention provides a battery cell cleaning device capable of reducing the area of ​​non-impregnated electrolyte in a battery cell, and a method for manufacturing a battery cell using the same.

[0011] In addition, the invention provides a battery cell cleaning device capable of preventing a decrease in capacity relative to the design of the battery cell, and a method for manufacturing a battery cell using the same.

[0012] In addition, the invention provides a battery cell cleaning device and a method for manufacturing a battery cell using the same, which can simplify the battery cell manufacturing process.

[0013] However, the technical problems that the present invention aims to solve are not limited to those described above, and other unmentioned problems will be clearly understood by those skilled in the art from the description of the invention below.

[0014] To solve the above objective, the present invention provides a battery cell cleaning device comprising: a main body portion configured to accommodate at least one battery cell in a liquid medium contained in an internal space; and a vibration portion mounted on the main body portion and configured to generate vibration and transmit the generated vibration to the liquid medium, wherein the vibration portion is configured to apply vibration toward both ends in the longitudinal direction of the battery cell through the liquid medium.

[0015] For example, the main body may include a fixing part that fixes the battery cell so that both ends of the battery cell in the longitudinal direction are maintained at a predetermined distance from the inner wall of the main body and are immersed in the liquid medium.

[0016] For example, the above fixing part may be configured to fix a cylindrical battery cell comprising an electrode assembly wound around a winding axis by stacking a first electrode, a separator, and a second electrode.

[0017] For example, the vibration unit may include a generation unit configured to generate an electrical signal; a conversion unit configured to convert the electrical signal received from the generation unit into mechanical vibration; and an application unit configured to apply the mechanical vibration converted from the conversion unit toward both ends in the longitudinal direction of the battery cell.

[0018] For example, the above-mentioned generating unit may be configured to generate an ultrasonic signal having a frequency of 20 kHz or more and 100 kHz or less.

[0019] For example, the above-mentioned conversion unit includes a piezoelectric element, and the piezoelectric element may be configured to convert an electrical signal received from the above-mentioned generation unit into ultrasonic vibration.

[0020] For example, the above-mentioned vibration members are provided in multiple numbers on the inner wall of the main body and are each positioned toward both ends in the longitudinal direction of the battery cell and can be controlled independently.

[0021] For example, the application unit may include a first application unit configured to apply mechanical vibration converted from the conversion unit toward one end in the longitudinal direction of the battery cell; and a second application unit configured to apply mechanical vibration converted from the conversion unit toward the other end in the longitudinal direction of the battery cell.

[0022] For example, it may include a circulation unit configured to supply and discharge a liquid medium contained in the internal space of the main body to circulate it.

[0023] In addition, the present invention provides a battery cell manufacturing method using a battery cell cleaning device according to various embodiments described above, comprising: an injection step of injecting an electrolyte into the battery cell; a sealing step of sealing the battery cell; an insertion step of inserting the battery cell into the internal space of the main body; and a cleaning step of applying vibration toward both ends in the longitudinal direction of the battery cell through the vibration unit, thereby cleaning the exterior of the battery cell while simultaneously inducing the electrolyte located in the longitudinal end regions of the battery cell to be impregnated into the central region.

[0024] For example, the battery cell may be a cylindrical battery cell comprising an electrode assembly formed by stacking a first electrode, a separator, and a second electrode and winding it around a winding axis.

[0025] For example, the above injection step may include a process of diffusing the electrolyte injected into the battery cell under vacuum conditions.

[0026] For example, it may include a circulation step of supplying and discharging a liquid medium into the internal space of the main body through the circulation section of the battery cell cleaning device.

[0027] The battery cell cleaning device and the battery cell manufacturing method using the same according to various embodiments of the present invention have the effect of improving the performance of the battery cell.

[0028] In addition, the battery cell cleaning device according to various embodiments and the battery cell manufacturing method using the same have the effect of improving the impregnation properties of the electrolyte.

[0029] In addition, the battery cell cleaning device according to various embodiments and the battery cell manufacturing method using the same have the effect of being able to clean foreign substances from the battery can.

[0030] In addition, the battery cell cleaning device according to various embodiments and the battery cell manufacturing method using the same have the effect of preventing a decrease in capacity relative to the design of the battery cell.

[0031] In addition, the battery cell cleaning device according to various embodiments and the battery cell manufacturing method using the same have the effect of simplifying the battery cell manufacturing process.

[0032] However, the effects obtainable through the present invention are not limited to those described above, and other unmentioned technical effects will be clearly understood by those skilled in the art from the description of the invention below.

[0033] FIG. 1 is a schematic diagram showing a battery cell cleaning device according to one embodiment of the present invention.

[0034] FIGS. 2 and FIGS. 3 are schematic diagrams illustrating embodiments of the battery cell cleaning device of FIG. 1.

[0035] Figure 4 is a diagram illustrating the flow of the electrolyte in a battery cell by the battery cell cleaning device of Figure 1.

[0036] FIGS. 5 to 7 are flowcharts of embodiments of a battery cell manufacturing method using the battery cell cleaning device of FIG. 1.

[0037] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the present invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.

[0038] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention; thus, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

[0039] In addition, the present invention includes various embodiments. For each embodiment, redundant descriptions of substantially identical or similar configurations are omitted, and the focus is on the differences.

[0040] Additionally, to aid in understanding the invention, the attached drawings are not drawn to actual scale, and the dimensions of some components may be exaggerated. Furthermore, the same reference numerals may be assigned to identical components in different embodiments.

[0041] Although terms such as "first," "second," etc., are used to describe various components, it goes without saying that these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless specifically stated otherwise, the first component may also be the second component.

[0042] Throughout the specification, unless specifically stated otherwise, each component may be singular or plural.

[0043] In the following, the statement that any configuration is placed on the "upper (or lower)" of a component or on the "upper (or lower)" of a component may mean not only that any configuration is placed in contact with the upper (or lower) surface of said component, but also that another configuration may be interposed between said component and any configuration placed on (or below) said component.

[0044] In addition, where it is stated that one component is "connected," "combined," or "connected" to another component, it should be understood that while the components may be directly connected or connected to each other, another component may be "interposed" between each component, or each component may be "connected," "combined," or "connected" through another component.

[0045] Singular expressions used in this specification include plural expressions unless the context clearly indicates otherwise. In this application, terms such as "composed of" or "comprising" should not be interpreted as necessarily including all of the various components or steps described in the specification, and should be interpreted as meaning that some of the components or steps may be omitted or additional components or steps may be included.

[0046] Meanwhile, although terms indicating directions such as up, down, left, right, front, and back may be used in this specification, these terms are used merely for convenience of explanation and may vary depending on the position or arrangement, rotation, or position of the observer, as is obvious to those skilled in the art of this invention.

[0047] The present invention may be implemented in the following embodiments, each independently. Furthermore, the present invention may be implemented in combination of two or more of the following embodiments. Each of the following embodiments may not only be implemented independently but may also be freely combined with one another.

[0048] For convenience of explanation, in this specification, the direction following the length direction of the winding axis of an electrode assembly wound in a jelly roll shape is referred to as the winding axis direction. The direction in which the electrode assembly is wound along the winding axis is referred to as the winding direction. Furthermore, the direction moving away from or closer to the winding axis of the electrode assembly is referred to as the radial direction.

[0049]

[0050] FIG. 1 is a schematic diagram showing a battery cell cleaning device (100) according to one embodiment of the present invention, and FIG. 2 and FIG. 3 are schematic diagrams illustrating embodiments of the battery cell cleaning device (100) of FIG. 1.

[0051] Referring to FIGS. 1 to 3, a battery cell cleaning device (100) according to one embodiment mainly comprises a main body part (110) and a vibration part (120).

[0052] The main body (110) may be configured to contain at least one battery cell (1) in a liquid medium (C) contained in an internal space.

[0053] The main body (110) is configured to accommodate a liquid medium (C) in a space formed inside, and this internal space can provide an appropriate volume so that the liquid medium (C) can be maintained at a certain level during the cleaning process.

[0054] Additionally, the main body (110) may be designed to accommodate at least one battery cell (1) to facilitate contact with a liquid medium (C), and may include a support structure or clamp, etc., to stably fix the battery cell (1) during the cleaning process.

[0055] The liquid medium (C) can perform the role of transferring energy to the surface and interior of the battery cell (1) within the main body (110), thereby contributing to the removal of contaminants from the battery cell (1) and the movement of the electrolyte (E).

[0056] The vibration unit (120) may be configured to be mounted on the main body (110) to generate vibration and to transmit the generated vibration to the liquid medium (C).

[0057] The vibration unit (120) can function to effectively reach the surface and interior of the battery cell (1) by transmitting vibrations to the liquid medium (C). Through this, the liquid medium (C) transmits vibrations to the battery cell (1) during the cleaning process, thereby increasing the efficiency of the cleaning process.

[0058] The vibration unit (120) may be configured to apply vibrations toward both ends of the battery cell (1) in the longitudinal direction through a liquid medium (C). At this time, the vibration unit (120) may contribute to effectively controlling or moving contaminants or uneven electrolyte (E) distribution concentrated at each end of the battery cell (1) during the cleaning process of the battery cell (1).

[0059] Accordingly, the battery cell cleaning device (100) according to the present embodiment can induce the movement of the electrolyte in a specific direction inside the battery cell (1) by applying vibrations toward one end in the longitudinal direction of the battery cell (1) and the other end positioned opposite thereto. In this process, the heat generated along with the vibrations can improve the fluidity of the electrolyte (E) contained inside the battery cell (1), thereby reducing the resistance to movement of the electrolyte (E) and achieving a more uniform distribution. As a result, the battery cell cleaning device (100) can move the electrolyte (E) to areas not impregnated with electrolyte that may exist inside the battery cell (1), thereby significantly improving the impregnation. In addition, by effectively removing foreign substances on the surface of the battery cell (1) that may occur during the electrolyte (E) injection process through vibrations, the complexity of the manufacturing process can be reduced and the efficiency of quality control can be increased.

[0060] Hereinafter, each configuration of the battery cell cleaning device (100) according to one embodiment of the present invention will be examined in detail.

[0061] A main body part (110) according to one embodiment may include a fixed part (111).

[0062] The fixing part (111) may be configured to fix the battery cell (1) so that both ends of the battery cell (1) in the longitudinal direction are maintained at a predetermined distance from the inner wall of the main body part (110). Through this, the battery cell (1) can be stably immersed in the liquid medium (C). In addition, the fixing part (111) can ensure that vibrations are transmitted uniformly throughout the battery cell (1) by maintaining the position of the battery cell (1) constant during the cleaning process. This structure can prevent the battery cell (1) from shaking or the vibration transmission efficiency from decreasing during the cleaning and movement of the electrolyte (E).

[0063] The fixing part (111) can be configured to fix, for example, a cylindrical battery cell (1). This allows the cylindrical battery cell (1) to be stably maintained within the main body (110) and optimizes the contact area with the liquid medium (C) during the cleaning process. Additionally, the fixing part (111) can be designed in a shape suitable for the external shape of the cylindrical battery cell (1) so that vibrations can be transmitted to both ends of the battery cell (1) in the longitudinal direction. This contributes to improving the movement and impregnation of the electrolyte (E).

[0064] The vibration unit (120) may include, for example, a generating unit (121) that generates an electric signal, a converting unit (122) that converts the generated electric signal into mechanical vibration, and an applying unit (123) that applies the converted mechanical vibration to both ends of the battery cell (1) in the longitudinal direction.

[0065] The generating unit (121) may be designed to generate an electrical signal. This electrical signal may be, for example, an ultrasonic signal having a frequency of 20 kHz or more and 100 kHz or less. The generated electrical signal may be transmitted to the conversion unit (122) through stable and efficient signal output and converted into mechanical vibration.

[0066] The conversion unit (122) may include a piezoelectric element or similar device that converts an electrical signal into contraction and expansion motion, thereby generating high-frequency vibration energy. The converted mechanical vibration can be transmitted to each of the longitudinal ends of the battery cell (1) through the application unit (123).

[0067] The application unit (123) can be designed to concentrate vibrations in a specific direction and transmit them uniformly to the surface of the battery cell (1). For example, the application unit (123) may be made of a cylindrical ultrasonic horn and may be positioned at a predetermined distance from both ends in the longitudinal direction of the battery cell (1). The vibrations applied by the ultrasonic waves of the application unit (123) may be applied once, or two or more times periodically or non-periodically.

[0068] The configuration of such a vibrating part (120) can promote the movement of the electrolyte (E) inside the battery cell (1) and improve the efficiency of the cleaning and impregnation process.

[0069] As illustrated in FIG. 2, as an example, the vibration unit (120) can be designed to generate ultrasonic vibrations through a single generating unit (121) and a conversion unit (122), and to transmit the generated vibrations to two application units (123) positioned toward both ends in the longitudinal direction of the battery cell (1). This method can provide a structure that ensures simplicity and efficiency of the design by unifying the generating unit (121) and the conversion unit (122), while also enabling the ultrasonic vibrations to be uniformly transmitted to both ends of the battery cell (1) through the two application units (123).

[0070] Both application units (123) can be designed to maintain appropriate directionality and vibration transmission paths to accurately transmit vibrations, such as ultrasonic vibrations, received from the conversion unit (122) to both ends in the longitudinal direction of the battery cell (1). By doing so, vibration loss can be minimized, and vibration energy can be concentrated in a specific area of ​​the battery cell (1) to maximize the movement of the electrolyte (E) and cleaning effect.

[0071] Accordingly, the battery cell cleaning device (100) according to the present embodiment does not require separate generation unit (121) and conversion unit (122) to be installed individually for each of the plurality of application units (123), so it can contribute to cost reduction and design simplification of the system.

[0072] As another example, as shown in FIG. 3, the vibrating part (120) may be provided with a plurality of vibrating parts (120a, 120b) on the inner wall of the main body part (110).

[0073] Each vibration unit (120a, 120b) can be independently positioned toward both ends in the longitudinal direction of the battery cell (1) and can be independently controlled. Specifically, each vibration unit (120a, 120b) can be designed to provide focused vibrations at one end and the other end in the longitudinal direction of the battery cell (1). By doing so, each vibration unit (120a, 120b) can concentrate ultrasonic vibrations on specific locations in the battery cell (1) to help the electrolyte (E) move effectively inside the battery cell (1), and can perform the role of removing contaminants and improving impregnation.

[0074] Since each vibration unit (120a, 120b) can be controlled independently, conditions such as different vibration intensities, frequencies, or application times can be arbitrarily set at both ends of the battery cell (1) in the longitudinal direction. Through this, optimized vibration conditions can be implemented according to the cleaning requirements of each location or the distribution state of the electrolyte (E). In addition, this independent control method enables maintenance of specific vibration units (120a, 120b) or differential operation under specific conditions during the battery cell (1) manufacturing process, thereby greatly increasing the flexibility and work efficiency of the system.

[0075] Accordingly, the battery cell cleaning device (100) according to the present embodiment allows for independent control of the application of ultrasonic vibrations according to requirements. Through this configuration, the movement of the electrolyte (E) and the cleaning effect are improved, thereby allowing the quality of the battery cell manufacturing process to be maintained more stably.

[0076] A battery cell cleaning device (100) according to one embodiment may include a circulation unit (130) connected to a main body (110). The circulation unit (130) may be configured to continuously circulate a liquid medium (C) within the main body (110) by supplying or discharging a liquid medium (C) contained in the internal space of the main body (110). To this end, the circulation unit (130) may be equipped with a storage tank for storing the liquid medium (C), a circulation pump, and a discharge valve, and a filtering device may be additionally provided to control the contamination level of the liquid medium (C) or maintain cleaning efficiency during the cleaning process. Through this configuration, the freshness of the liquid medium (C) can be maintained during the cleaning process, and contaminants can be prevented from accumulating in the main body (110).

[0077] Additionally, a battery cell cleaning device (100) according to one embodiment may include a drying unit (140) connected to a main body (110). The drying unit (140) may include a hot air dryer or a vacuum drying device to remove residual liquid medium (C) from the surface and inside of the battery cell (1) after the cleaning process is completed. The drying unit (140) may be designed to operate while maintaining an appropriate temperature and humidity to shorten the drying time and prevent physical damage to the battery cell (1). Through this, the battery cell (1) can be transferred to a subsequent process in a dried state, thereby improving the efficiency of the manufacturing process.

[0078] In addition, a battery cell cleaning device (100) according to one embodiment may include a control unit (150) configured to control each component of the battery cell cleaning device (100).

[0079] The control unit (150) integrally controls the operation of each component connected to the main body (110), for example, the vibration unit (120), the circulation unit (130), and the drying unit (140), and can monitor the operating status of each component in real time and output control signals to maintain optimal cleaning conditions. The control unit (150) may include a user interface that allows the user to set cleaning conditions (e.g., ultrasonic frequency, vibration intensity, circulation speed, drying temperature, etc.) and can support maintaining the quality of the cleaning process consistently through an automated process.

[0080] Such a configuration enables the battery cell cleaning device (100) of the present invention to operate efficiently and precisely, and can contribute to quality control throughout the cleaning process and increase productivity of the manufacturing process.

[0081]

[0082] FIG. 4 is a diagram for explaining the flow of the electrolyte (E) of the battery cell (1) by the battery cell cleaning device (100) of FIG. 1.

[0083] The battery cell (1) applied to the battery cell cleaning device (100) of the present invention may be a cylindrical battery cell. For example, the battery cell (1) may be a cylindrical battery cell in which the ratio of the form factor (defined as the ratio of the diameter of the cylindrical battery cell to the height, i.e., the ratio of the diameter to the height) is approximately greater than 0.4.

[0084] Here, the form factor may refer to a value representing the diameter and height of a cylindrical battery cell. The cylindrical battery cell may be a 46110 cell, a 48750 cell, a 48110 cell, a 48800 cell, or a 46800 cell by applying the numerical value representing the form factor. Here, the first two digits represent the diameter of the cell, the next two digits represent the height of the cell, and the last digit 0 indicates that the cross-section of the cell is circular.

[0085] Additionally, the battery cell (1) may be a cylindrical battery cell, for example, having a form factor ratio (ratio of diameter along the radial direction to height along the core axis direction) greater than approximately 0.4. For example, the diameter of the battery cell (1) may be 40 mm to 50 mm, and the height may be 60 mm to 130 mm. The form factor of the battery cell (1) may be, for example, 46110, 4875, 48110, 4880, or 4680.

[0086] However, the shape of the battery cell (1) according to the present invention is not limited by the above and can be applied to batteries of other shapes. For example, it can be applied to prismatic batteries.

[0087] Referring to FIG. 4, the battery cell (1) applied to the battery cell cleaning device (100) may largely include a battery can (10) and an electrode assembly (20).

[0088] The battery can (10) may be a cylindrical structure for a cylindrical battery cell. In this case, a side wall member may form the side of the cylinder of the battery can, and a bottom member may be connected to the side wall member to form one end of the cylinder. That is, the bottom member becomes the closed part of the battery can (10), and the other end of the battery can (10) facing the bottom member may be open to become an opening.

[0089] The electrode assembly (20) can be accommodated inside the battery can (10) through the opening of the battery can (10).

[0090] The electrode assembly (20) may be configured such that the first electrode and the second electrode and the separator interposed between them are wound around a winding axis. After the winding is completed, the electrode assembly (20) may be in the form of a jelly-roll. When viewed from the top or bottom in the direction of the winding axis of the electrode assembly (20), the outer shape of the electrode assembly (20) along the circumferential direction may be circular. However, the structure of the electrode assembly (20) is not limited by this example and may have a winding structure well known in the art.

[0091] The first electrode and the second electrode may be manufactured in the form of a sheet. The first electrode and the second electrode may be configured such that an active material layer is coated on the surface of at least a portion of a metal foil. The first electrode and the second electrode may have a retaining portion region coated with an active material layer and a non-retaining portion region not coated with an active material layer.

[0092] An electrode assembly (20) according to one embodiment is designed to include more active material layers to maximize the energy density of the battery cell (1) and can be manufactured in a jelly-roll form by tightly winding them. While this structure is advantageous for increasing energy density, as the electrode assembly (20) is tightly wound, it may result in physical limitations for the electrolyte (E) to penetrate into the electrode assembly (20). In particular, the low porosity of each electrode may act as one of the main causes that make it difficult for the electrolyte (E) to move effectively into the electrode assembly (20).

[0093] As a result, the electrolyte (E) is relatively concentrated in the longitudinal end regions (P1, P3) of the battery cell (1), and there is a possibility that an unimpregnated region is formed in the longitudinal central region (P2) of the battery cell (1) where the electrolyte (E) does not sufficiently penetrate. This unimpregnated region indicates that the electrolyte (E) is not uniformly distributed throughout the electrode assembly (20), and thus the movement of cations (Li+) within the electrode assembly (20) may occur inefficiently.

[0094] Consequently, the unimpregnated area of ​​the electrode assembly (20) can cause a decrease in the overall capacity of the battery cell (1), which can lead to a decrease in energy density and battery performance.

[0095] Accordingly, the impregnation of the battery cell (1) can be improved by using the battery cell cleaning device (100) of the present invention.

[0096] As described above, the battery cell cleaning device (100) of the present invention can induce the electrolyte (E) to be distributed more uniformly inside the battery cell (1) by applying vibration, for example, ultrasonic vibration, to each of the longitudinal ends of the battery cell (1).

[0097] For example, the electrolyte (E) relatively concentrated in the longitudinal end regions (P1, P3) of the battery cell (1) can be moved to the unimpregnated region formed in the longitudinal central region (P2) of the battery cell (1) through the action of ultrasonic vibration energy. This flow process enables an even distribution of the electrolyte (E) within the electrode assembly (20), thereby significantly improving impregnation.

[0098] In addition, the heat generated by such ultrasonic vibrations can lower the viscosity of the electrolyte (E) and promote the movement of the electrolyte (E). That is, as the concentration of the electrolyte (E) is lowered, penetration into the electrode assembly (20) becomes easier, and an effective distribution of the electrolyte (E) can be achieved throughout the electrode assembly (20). This effect can contribute to improving the electrochemical performance of the battery cell (1) and preventing a decrease in overall capacity.

[0099] At the same time, ultrasonic vibration can also be usefully applied during the battery cell (1) cleaning process. Foreign substances present on the outside of the battery can (10) can be effectively removed by ultrasonic vibration, and as a result, additional cleaning processes can be omitted, thereby simplifying the manufacturing process.

[0100] Accordingly, the battery cell cleaning device (100) of the present invention can simultaneously improve the impregnation of the electrolyte (E) and the cleanliness of the battery cell (1), thereby increasing the efficiency of the manufacturing process and optimizing battery performance and quality.

[0101]

[0102] In addition, a method for manufacturing a battery cell (1) can be performed using the battery cell cleaning device (100) described above with reference to FIGS. 1 to 4.

[0103] FIGS. 5 to 7 are flowcharts of embodiments of a method for manufacturing a battery cell (1) using the battery cell cleaning device (100) of FIG. 1.

[0104] A battery cell manufacturing method according to one embodiment using the aforementioned battery cell cleaning device (100) may largely include a liquid injection step, a sealing step, an insertion step, and a cleaning step.

[0105] The injection step is a step of injecting an electrolyte (E) into the interior of a battery cell (1), so that the electrolyte (E) comes into contact with the electrode assembly (20) to achieve initial impregnation. This step can be precisely controlled to inject an appropriate amount of electrolyte (E) into the interior of the battery cell (1), and the injection pressure and speed can be adjusted considering the structural characteristics of the electrode assembly (20) (e.g., high active material density and low porosity). For example, the battery cell (1) may be a cylindrical battery cell comprising an electrode assembly (20) that is wound around a winding axis by stacking a first electrode, a separator, and a second electrode.

[0106] The sealing step is a step of sealing the battery cell (1) so that the electrolyte (E) injected inside does not leak out. This step includes a process of sealing the opening of the battery can (10) of the battery cell (1), and after sealing, the electrolyte (E) is stably maintained inside the battery cell (1).

[0107] The insertion step is a step of inserting a sealed battery cell (1) into the internal space of the main body (110) of the battery cell cleaning device (100). In this step, for example, the battery cell (1) can be stably fixed by the fixing part (111) of the main body (110) and positioned in a location optimized for the subsequent ultrasonic vibration and cleaning process.

[0108] The cleaning step is a step of applying ultrasonic vibrations toward both ends of the battery cell (1) in the longitudinal direction using the vibration unit (120) of the battery cell cleaning device (100). This step simultaneously performs two main effects. First, the ultrasonic vibrations perform a cleaning process by removing foreign substances from the outer surface of the battery cell (1). This is achieved through cavitation induced by the ultrasonic vibrations and the flow action of a fluid medium (C), for example, a cleaning liquid. Second, it induces an impregnation process that moves the electrolyte (E), which is relatively concentrated in the longitudinal end regions (P1, P3) of the battery cell (1), to the central region (P2). In this process, the heat generated by the ultrasonic vibrations reduces the viscosity of the electrolyte (E), thereby enhancing mobility and helping the electrolyte (E) to permeate uniformly into the unimpregnated area of ​​the electrode assembly (20).

[0109] In this way, the battery cell manufacturing method according to the present embodiment can simultaneously improve the impregnation of the electrolyte (E) and the cleanliness of the battery cell (1), thereby maximizing battery performance and the efficiency of the manufacturing process.

[0110] The injection step may include a process of injecting an electrolyte (E) into the interior of a battery cell (1), along with an additional process of diffusing the injected electrolyte (E) within an electrode assembly (20) through pressure control. This additional process may help the electrolyte (E) come into complete contact with the electrode assembly (20) and penetrate into the pores of the electrode assembly.

[0111] For example, in a vacuum state, air inside the battery cell (1) is removed to reduce the resistance to the inflow of the electrolyte (E) and enable faster and more uniform impregnation. Additionally, to further diffuse the injected electrolyte (E) into the electrode assembly (20), pressure may be applied to the battery cell (1) or maintained for a specific period of time so that the electrolyte (E) permeates the entire surface and depth of the electrode assembly (20).

[0112] This impregnation process minimizes unimpregnated areas that may occur due to the high-density structure of the electrode assembly (20) and can contribute to stabilizing the electrochemical performance of the battery cell (1). As a result, the injection step optimizes the distribution of the electrolyte (E) in the initial stage of the battery cell manufacturing process, thereby preventing quality issues in subsequent processes and improving battery capacity and lifespan.

[0113] The battery cell manufacturing method according to the present embodiment may include a circulation step of supplying and discharging a liquid medium (C) into the internal space of the main body (110) using the circulation unit (130) of the battery cell cleaning device (100) to circulate it. The circulation step may, for example, allow the liquid medium (C) to continuously move within the main body (110) during the cleaning step to effectively remove contaminants attached to the surface and external structure of the battery cell (1). The circulation step may be performed temporarily or periodically throughout the manufacturing process, and the flow rate, temperature, or circulation time of the liquid medium (C) may be adjusted to maximize cleaning efficiency under specific conditions.

[0114] Additionally, the cleaning step may include a drying step in which, after the cleaning process of the battery cell (1) is completed, the liquid medium (C) residue remaining on the surface and inside the battery cell (1) is removed using the drying unit (140) of the battery cell cleaning device (100). The drying step can prevent the possibility of contamination in subsequent processes and ensure manufacturing quality by treating the battery cell (1) with a hot air drying or vacuum drying method to evaporate the remaining liquid components.

[0115] In particular, the drying step can be designed to maintain appropriate temperature and humidity conditions to prevent damage to the battery cell (1). This prevents corrosion or performance degradation caused by residue of the liquid medium (C) and allows the battery cell (1) to be transferred to the next process in a completely cleaned and dried state.

[0116] Accordingly, the battery cell manufacturing method according to the present embodiment can improve the cleanliness and electrochemical performance of the battery cell (1) simultaneously by using a battery cell cleaning device (100), and contribute to increasing the overall quality and efficiency of the manufacturing process.

[0117]

[0118] As described above, although the present invention has been explained by limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs.

[0119] [Explanation of the symbol]

[0120] 1: Battery cell

[0121] 10: Battery can

[0122] 20: Electrode assembly

[0123] 100: Battery cell cleaning device

[0124] 110: Main body

[0125] 111: Fixed part

[0126] 120, 120a, 120b: Vibrating part

[0127] 121: Generation section

[0128] 122: Conversion section

[0129] 123: Authorization Department

[0130] 1231: First Authorization Department

[0131] 1232: Second Authorization Department

[0132] 130: Circulatory section

[0133] 140: Drying section

[0134] 150: Control unit

[0135] E: Electrolyte

[0136] C: Liquid media

[0137] P1, P2, P3: Area

Claims

1. A main body configured to accommodate at least one battery cell in a liquid medium contained in an internal space; and It includes a vibration unit mounted on the main body to generate vibration and configured to transmit the generated vibration to the liquid medium. The above-mentioned vibrating part is, A battery cell cleaning device characterized by being configured to apply vibration toward both ends in the longitudinal direction of the battery cell through the above liquid medium.

2. In Paragraph 1, The above main body part is, A battery cell cleaning device characterized by including a fixing part for fixing the battery cell such that both ends of the battery cell in the longitudinal direction are maintained at a predetermined distance from the inner wall of the main body and are immersed in the liquid medium.

3. In Paragraph 2, The above fixed part is, A battery cell cleaning device characterized by being configured to fix a cylindrical battery cell comprising an electrode assembly wound around a winding axis by stacking a first electrode, a separator, and a second electrode.

4. In Paragraph 1, The above-mentioned vibrating part is, A generator configured to generate an electrical signal; A converter configured to convert the electrical signal received from the above-mentioned generating unit into mechanical vibration; and A battery cell cleaning device characterized by including an application unit configured to apply mechanical vibration converted from the above conversion unit toward both ends in the longitudinal direction of the battery cell.

5. In Paragraph 4, The above generating unit is, A battery cell cleaning device characterized by being configured to generate an ultrasonic signal having a frequency of 20 kHz or more and 100 kHz or less.

6. In Paragraph 4, The above conversion unit is, A battery cell cleaning device comprising a piezoelectric element, wherein the piezoelectric element is configured to convert an electrical signal received from the generating unit into an ultrasonic vibration.

7. In Paragraph 4, The above authorization unit is, A first application unit configured to apply mechanical vibration converted from the above conversion unit toward one end in the longitudinal direction of the battery cell; and A battery cell cleaning device characterized by including a second application unit configured to apply mechanical vibration converted from the above conversion unit toward the other end in the longitudinal direction of the battery cell.

8. In Paragraph 4, The above-mentioned vibrating part is, A battery cell cleaning device characterized by having a plurality of units provided on the inner wall of the main body, each positioned toward both ends in the longitudinal direction of the battery cell and independently controlled.

9. In Paragraph 1, A battery cell cleaning device characterized by including a circulation unit configured to supply and discharge a liquid medium contained in the internal space of the main body to circulate it.

10. A method for manufacturing a battery cell using a battery cell cleaning device according to any one of claims 1 to 9, wherein A fluid injection step of injecting an electrolyte into the battery cell; A sealing step for sealing the above battery cell; An insertion step of inserting the battery cell into the internal space of the main body; and A method for manufacturing a battery cell, characterized by including a cleaning step of applying vibration toward both ends in the longitudinal direction of the battery cell through the vibration unit, thereby cleaning the exterior of the battery cell while simultaneously inducing the electrolyte located in the longitudinal end regions of the battery cell to be impregnated into the central region.

11. In Paragraph 10, The above battery cell is, A method for manufacturing a battery cell, characterized by comprising a cylindrical battery cell including an electrode assembly formed by stacking a first electrode, a separator, and a second electrode and winding it around a winding axis.

12. In Paragraph 10, The above injection step is, A method for manufacturing a battery cell, characterized by including a process of diffusing an electrolyte injected into the battery cell under vacuum conditions.

13. In Paragraph 10, A method for manufacturing a battery cell, characterized by including a circulation step of supplying and discharging a liquid medium into the internal space of the main body through the circulation section of the battery cell cleaning device.

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