Formation device and formation method for secondary battery

Abstract

Disclosed is a formation device and a formation method for a secondary battery. The formation device includes a temperature controller for controlling a temperature of the secondary battery, a temperature sensor for measuring the temperature of the secondary battery, a charge / discharge unit including a probe contacting a terminal of the secondary battery, a vacuum tube for removing a gas inside the secondary battery, and a controller for charging the secondary battery until a state of charge of the secondary battery reaches a termination capacity, wherein the controller controls the temperature controller to maintain the temperature of the secondary battery measured by the temperature sensor at a set temperature range during the charging, and controls the vacuum tube during the charging, and wherein the termination capacity can be 40% to 90%.

Description

Technical Field

[0001] This disclosure relates to a formation apparatus and a formation method for secondary batteries. Background Technology

[0002] Unlike primary batteries, which are not designed for (re)charging, secondary (or rechargeable) batteries are designed to discharge and be recharged. Low-capacity secondary batteries are used in portable small electronic devices such as smartphones, feature phones, laptops, digital cameras, and camcorders, while high-capacity secondary batteries are widely used as power sources for driving motors in hybrid and electric vehicles, as well as for storing electricity (e.g., household and / or utility-scale power storage). A secondary battery typically includes an electrode assembly containing positive and negative electrodes, a housing that houses the electrode assembly, and electrode terminals connected to the electrode assembly.

[0003] The formation process of a secondary battery is a step that activates and stabilizes the battery's initial performance during battery manufacturing. The formation process occurs during the initial charging and discharging of the secondary battery, and the battery's function is optimized as ions are inserted into and extracted from the electrodes through the formation process. Additionally, a solid electrolyte interface (SEI) layer is formed during the formation process. The SEI layer, located between the electrodes and the electrolyte, protects the electrodes and thus determines the battery's lifespan and performance.

[0004] The information disclosed herein in the Background section is intended to enhance understanding of the background of this disclosure, and therefore may contain information that does not constitute related (or prior art). Summary of the Invention

[0005] This disclosure provides a formation apparatus and a formation method for secondary batteries.

[0006] However, the technical problems to be solved by this disclosure are not limited to those described herein. Those skilled in the art will clearly understand, through the description of this disclosure herein, other problems not mentioned herein, as well as aspects and features of this disclosure that will solve these problems.

[0007] According to embodiments of this disclosure for solving technical problems, a formation apparatus for a secondary battery includes: a temperature controller for controlling the temperature of the secondary battery; a temperature sensor for measuring the temperature of the secondary battery; a charging / discharging unit including probes contacting terminals of the secondary battery; a vacuum tube for removing gas from inside the secondary battery; and a controller for charging the secondary battery until the state of charge of the secondary battery reaches a termination capacity, wherein the controller controls the temperature controller to maintain the temperature of the secondary battery measured by the temperature sensor within a set temperature range during charging, and controls the vacuum tube during charging, and wherein the termination capacity can be from 40% to 90%.

[0008] According to embodiments of this disclosure, the temperature range can be from 35°C to 65°C.

[0009] According to embodiments of this disclosure, a secondary battery is mounted on a tray, and the temperature controller may include a heating element for heating the tray.

[0010] According to embodiments of this disclosure, the temperature controller may include a fan for blowing cool air toward the tray.

[0011] According to embodiments of this disclosure, the probe may include a first probe and a second probe. The first probe is electrically connected to a first terminal of a first electrode of a secondary battery, and the second probe is electrically connected to a second terminal of a second electrode of a secondary battery. A temperature sensor may be connected to either the first probe or the second probe, and a vacuum tube may be in contact with the electrolyte injection port of the secondary battery.

[0012] According to embodiments of this disclosure, the inside of the vacuum tube can be under negative pressure.

[0013] According to embodiments of this disclosure, the controller can control the charging / discharging unit to charge the secondary battery at a C-rate of 0.2C to 1.2C until the secondary battery's state of charge reaches its termination capacity.

[0014] According to embodiments of this disclosure, the controller can control the charging / discharging unit to charge the secondary battery multiple times at different C-rates during charging.

[0015] According to embodiments of this disclosure for solving technical problems, a formation method for a secondary battery includes the following steps: a preheating step for preheating the secondary battery; a charging step for charging the secondary battery until the state of charge (SOC) of the secondary battery reaches the termination capacity (%); a temperature control step for maintaining the secondary battery within a set temperature range until the state of charge (SOC) of the secondary battery reaches the termination capacity (%); and a degassing step for removing gas from inside the secondary battery, wherein the charging step, the temperature control step, and the degassing step are performed in parallel, and wherein the termination capacity can be from 40% to 90%.

[0016] According to embodiments of this disclosure, the temperature range can be from 35°C to 65°C.

[0017] According to embodiments of this disclosure, the formation method for a secondary battery may further include a pre-aging step of injecting electrolyte into the secondary battery and placing the secondary battery as is before the preheating step.

[0018] According to embodiments of this disclosure, in the preheating step, the secondary battery can be preheated until the temperature of the secondary battery reaches 35°C to 65°C.

[0019] According to embodiments of this disclosure, the preheating step may include: stacking a tray on which a secondary battery is loaded and placing the tray into a preheater; connecting the tray to the heating part of the preheater; and preheating the tray to a predetermined specific temperature between 35°C and 65°C.

[0020] According to embodiments of this disclosure, the secondary battery can be charged within a voltage range of 0.1V to 4.5V during the charging step.

[0021] According to embodiments of this disclosure, in the temperature control step, heating can be performed by heating the tray on which the secondary battery is mounted, and cooling can be performed by blowing cold air toward the tray.

[0022] According to embodiments of this disclosure, the tray may include a heating plate mounted on its lower part, and the temperature control step may be performed by increasing the temperature of the heating plate.

[0023] According to embodiments of this disclosure, in the degassing step, the gas inside the secondary battery can be removed by bringing the vacuum tube into contact with the electrolyte injection port of the secondary battery, and the inside of the vacuum tube can be under negative pressure.

[0024] According to embodiments of this disclosure, the formation method for a secondary battery may further include the steps of releasing the vacuum tube from the electrolyte injection port and sealing the electrolyte injection port after the degassing step.

[0025] According to embodiments of this disclosure, the formation method for a secondary battery may further include a step of transferring the secondary battery to a formation apparatus between a preheating step and a charging step.

[0026] According to embodiments of this disclosure, in the charging step, the secondary battery can be charged multiple times at different C-rates ranging from 0.2C to 1.2C until the state of charge of the secondary battery reaches its termination capacity.

[0027] According to some embodiments of this disclosure, by performing a formation apparatus and method that simultaneously charges a secondary battery at a high rate under high-temperature conditions and degassing, gas generation in the electrode material at high temperatures can be maximized, and gas removal can be maximized. Therefore, the generation of byproducts due to side reactions within the secondary battery is suppressed, and battery quality can be improved.

[0028] According to some embodiments of this disclosure, a stable film can be formed on the electrode surface by reducing the mechanical or electrochemical stress received by the electrode during high-rate charging, thus enabling the manufacture of a secondary battery with a stable structure.

[0029] According to some embodiments of this disclosure, the charging step, temperature control step, and degassing step are performed in parallel in a single device, which can improve the production efficiency of secondary batteries by simplifying the formation process.

[0030] According to some embodiments of this disclosure, the life characteristics, performance, and quality of secondary batteries produced by a formation apparatus and formation method that simultaneously degassing the secondary battery at a high rate under high temperature conditions can be improved.

[0031] However, the aspects and features of this disclosure are not limited to those described herein, and those skilled in the art will clearly understand other aspects and features not mentioned from the detailed description described herein. Attached Figure Description

[0032] The accompanying drawings illustrate embodiments of the present disclosure and, together with the detailed description thereof, further describe aspects and features of the disclosure. Therefore, the present disclosure should not be construed as limited to the drawings.

[0033] Figure 1 This is a schematic diagram of a formation apparatus according to an embodiment of the present disclosure.

[0034] Figure 2 This is a flowchart illustrating a formation method according to an embodiment of the present disclosure.

[0035] Figure 3 This is a charging recipe table showing the charging process performed step by step in a formation apparatus according to an embodiment of the present disclosure.

[0036] Figure 4 It is a time-voltage curve used to illustrate the operation method of the formation apparatus and the formation method according to embodiments of the present disclosure.

[0037] Figure 5 This is a schematic diagram of a tray according to an embodiment of the present disclosure.

[0038] Figure 6 It is a graph showing the results of evaluating the internal pressure changes of a secondary battery that has undergone formation.

[0039] Figure 7 It is a graph showing the results of evaluating the thickness change of a secondary battery that has undergone formation.

[0040] Figure 8 This is an XPS curve showing the surface analysis results of the positive electrode material of the secondary battery.

[0041] Figure 9 This is a graph showing the results of evaluating the crystal structure of the cathode material of a secondary battery using Raman spectroscopy.

[0042] Figure 10 This is a graph showing the XRD analysis results of the positive electrode material of a secondary battery.

[0043] Figure 11 This is a graph showing the results of evaluating the lifetime characteristics of a secondary battery that has undergone charging and discharging.

[0044] Figure 12 This is a graph showing the results of evaluating the internal resistance based on the charge and discharge life of a secondary battery that has already undergone formation.

[0045] Figure 13 This is a graph showing the results of evaluating the capacity based on the storage time of a secondary battery that has undergone formation.

[0046] Figure 14 This is a graph showing the results of evaluating the internal resistance based on the storage time of a secondary battery that has undergone formation. Detailed Implementation

[0047] In the following, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The terms or words used in this specification and claims are not to be construed as having a general or dictionary meaning, but should be interpreted as consistent with the technical concept of the present disclosure, based on the principle that the inventor may be his / her own lexicographer to appropriately define the concepts of the terms in order to best describe his / her disclosure.

[0048] The embodiments described in this specification and the constructions shown in the accompanying drawings are merely some of the embodiments of this disclosure and do not represent all the technical spirit, aspects, and features of this disclosure. Therefore, it should be understood that various equivalents and modifications may exist to replace or modify the embodiments described herein at the time of filing.

[0049] It will be understood that when an element or layer is referred to as being "on," "connected to," or "bonded to" another element or layer, the element or layer may be directly on, directly connected to, or directly bonded to the other element or layer, or one or more intermediary elements or intermediary layers may be present. When an element or layer is referred to as being "directly on," "directly connected to," or "directly bonded to" another element or layer, no intermediary element or intermediary layer is present. For example, when a first element is described as being "bonded" or "connected" to a second element, the first element may be directly bonded to or directly connected to the second element, or the first element may be indirectly bonded to or indirectly connected to the second element via one or more intermediary elements.

[0050] In the figures, the dimensions of various elements, layers, etc., may be exaggerated for clarity. The same reference numerals denote the same elements. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. Furthermore, when describing embodiments of this disclosure, the use of "may" refers to "one or more embodiments of this disclosure." When expressions such as "at least one of..." and "any one of..." follow a list of elements, they modify the entire list of elements, not individual elements within that list. When a list of elements A, B, and C is specified using phrases such as "at least one of A, B, and C," "at least one of A, B, or C," "at least one selected from the group of A, B, and C," or "at least one selected from A, B, and C," the phrase may refer to any suitable combination (or subset) of A, B, and C, and all suitable combinations (or subsets), such as A, B, C, A and B, A and C, B and C, or A and B and C. As used herein, the term “use” and its variations may be considered synonymous with the term “utilize” and its variations, respectively. As used herein, the terms “substantially,” “about,” and similar terms are used as approximate terms rather than as terms of degree, and are intended to account for inherent biases in measurements or calculations that will be recognized by one of ordinary skill in the art.

[0051] It will be understood that although the terms first, second, third, etc., may be used herein to describe various elements, components, regions, layers, and / or portions, these elements, components, regions, layers, and / or portions should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or portion from another element, component, region, layer, or portion. Therefore, without departing from the teachings of the exemplary embodiments, the first element, first component, first region, first layer, or first portion discussed herein may be referred to as a second element, second component, second region, second layer, or second portion.

[0052] For ease of description, spatial relative terms such as “below,” “under,” “lower,” “above,” and “upper” are used herein to describe the relationship between one element or feature and another element(s) shown in the figures. It will be understood that, in addition to the orientation depicted in the figures, the spatial relative terms are also intended to cover different orientations of the device in use or operation. For example, if the device in the figures is flipped, an element described as “below” or “under” other elements or features will subsequently be oriented “above” or “above” said other elements or features. Thus, the term “below” can cover both above and below orientations. The device may be otherwise oriented (rotated 90 degrees or in other orientations), and the spatial relative descriptive terms used herein should be interpreted accordingly.

[0053] The terminology used herein is for the purpose of describing embodiments of this disclosure and is not intended to limit the disclosure. As used herein, unless the context clearly indicates otherwise, the singular forms “a” and “an” are also intended to include the plural forms. It will also be understood that when the terms “comprising,” “including,” and / or variations thereof are used in this specification, it indicates the presence of the stated features, integers, steps, operations, elements, and / or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0054] Furthermore, any numerical range disclosed and / or described herein is intended to include all subranges with the same numerical precision contained within the described range. For example, the range “1.0 to 10.0” is intended to include all subranges between the described minimum value 1.0 and the described maximum value 10.0 (inclusive), i.e., having a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0, such as 2.4 to 7.6. Any maximum numerical limit described herein is intended to include all lower numerical limits contained therein, and any minimum numerical limit described in this specification is intended to include all higher numerical limits contained therein. Therefore, the applicant reserves the right to amend this specification and the claims to expressly describe any subranges contained within the range expressly described herein.

[0055] Referring to two compared elements, features, etc., as “identical” can mean that they are “substantially identical.” Therefore, the phrase “substantially identical” can include cases with deviations considered low in the art (e.g., 5% or less). Additionally, when a parameter is said to be uniform in a given region, it can mean that it is uniform in terms of average value.

[0056] Throughout this specification, unless otherwise stated, each element may be singular or plural.

[0057] Arranging any element "above (or below)" or "on (below)" another element can mean that any element can be positioned to contact the upper (or lower) surface of the element, and that the other element can be positioned between the element and any element positioned on (or below) the element.

[0058] Additionally, it will be understood that when a component is referred to as “linked,” “combined,” or “connected” to another component, these components can be directly “combined,” “linked,” or “connected” to each other, or another component can be “placed” between these components.

[0059] Throughout this specification, unless otherwise stated, when “A and / or B” is stated, it means A, B, or A and B. That is, “and / or” includes any or all combinations of the listed items. Unless otherwise stated, when “C to D” is stated, it means C or greater and D or less.

[0060] The terminology used in this specification is for describing examples of this disclosure and is not intended to limit this disclosure.

[0061] Figure 1 This is a schematic diagram of a formation apparatus according to an embodiment of the present disclosure.

[0062] The formation apparatus 100 for a secondary battery according to an embodiment of the present disclosure may include a temperature controller TC for controlling the temperature of the secondary battery, a temperature sensor 140 for measuring the temperature of the secondary battery, a charging / discharging unit 150, a vacuum tube 160 for removing gas from inside the secondary battery, and a controller 170.

[0063] By using an automated system capable of processing multiple secondary cells simultaneously, the formation process using the formation apparatus 100 can be performed efficiently. The formation apparatus 100 can precisely control the voltage, current, and temperature of each secondary cell. This allows the formation apparatus 100 to minimize imbalances between secondary cells and reduce the initial defect rate.

[0064] For example, such as Figure 1 As shown, tray 110 consists of four rows (1R, 2R, 3R, 4R), and can hold 24 secondary batteries in each row. Therefore, one formation device 100 can form a total of 96 secondary batteries at a time. In this case, the charge / discharge unit 150, temperature sensor 140, and vacuum tube 160 in the formation device 100 can be arranged in four rows.

[0065] In this disclosure, prismatic secondary batteries are described as examples of secondary batteries, but this disclosure is not limited thereto; secondary batteries can be cylindrical, pouch-shaped, coin-shaped, or needle-shaped. Figure 1 The diagram shows a formation apparatus 100 for a prismatic secondary battery, but for formation apparatuses for other types of secondary batteries, the detailed structure of the apparatus may vary depending on the location of the terminals, electrolyte injection port, etc., of the secondary battery and the shape of the casing.

[0066] Reference Figure 1According to an embodiment, the charging / discharging unit 150 may include probes 152a and 152b. Probes 152a and 152b may include a first probe 152a and a second probe 152b. The first probe 152a is electrically connected to a first terminal of a first electrode of the secondary battery, and the second probe 152b is electrically connected to a second terminal of a second electrode of the secondary battery. When the first electrode is positive and the second electrode is negative, the first terminal may be a positive terminal and the second terminal may be a negative terminal. Alternatively, when the first electrode is negative and the second electrode is positive, the first terminal may be a negative terminal and the second terminal may be a positive terminal.

[0067] The terminals of the secondary battery may be exposed outside the housing and may contact or connect to probes 152a and 152b. The terminals of the secondary battery may be electrically connected via electrode tabs or electrode leads to electrodes included in an electrode assembly housed inside the secondary battery housing.

[0068] Probes 152a and 152b can connect the charging / discharging unit 150 and the secondary battery via connections to the terminals of the secondary battery to supply current and voltage to or recover current and voltage from the secondary battery. Furthermore, probes 152a and 152b can measure the voltage, current, and other parameters of the secondary battery in real time and transmit the data to the control system. Additionally, probes 152a and 152b can monitor the status of the secondary battery in real time to detect conditions such as overcharging, over-discharging, and overheating, and safely control the charging / discharging unit 150.

[0069] The charging / discharging unit 150 according to the embodiment may further include a charging / discharging circuit, a power supply unit, a control system, a data collection and monitoring device, etc. The power supply unit may be a device for supplying current to or recovering current from the secondary battery. For example, the power supply unit may supply a constant current or voltage during charging and may recover a constant current or voltage during discharging. The power supply unit may operate in CC (constant current) and CV (constant voltage) modes to perform various charging / discharging modes.

[0070] The control system of the charging / discharging unit 150 can be a system for real-time monitoring and control of voltage, current, etc., during the charging / discharging process. The control system can automatically adjust the charging / discharging process according to the state of the secondary battery and minimize damage to the secondary battery by preventing overcharging or over-discharging. The control system can be software for controlling charging / discharging and visually displaying data. This allows the user to monitor the charging / discharging state of the secondary battery and manage the charging / discharging process. Furthermore, various charging / discharging conditions can be set. The charging / discharging conditions according to an embodiment will be described later.

[0071] The data collection and monitoring device of the charging / discharging unit 150 can be a system for collecting and analyzing data generated during charging / discharging. For example, the data collection and monitoring device can evaluate the performance of the secondary battery by recording various parameters such as voltage, current, charging capacity, and discharging capacity in real time.

[0072] The temperature controller TC according to an embodiment may include a heating element 120 for heating a tray 110 on which secondary batteries are loaded. The tray 110 may provide storage space for loading multiple secondary batteries. The heating element 120 may raise the temperature of the secondary batteries by heating the tray 110. The heating element 120 may be disposed at the bottom of the tray 110 to uniformly heat the loaded secondary batteries. (See below for further details.) Figure 5 Describe the characteristics of the heating element 120.

[0073] The temperature controller TC may also include cooling sections 130a, 130b, and 130c for the cooling tray 110. For example, as Figure 1 As shown, cooling units 130a, 130b, and 130c may include fans for blowing cool air toward tray 110. The fans may include a first fan 130a, a second fan 130b, and a third fan 130c to uniformly cool the entire tray 110. However, this disclosure is not limited thereto, and fans of various numbers and positions may be used.

[0074] Reference Figure 1 The first fan 130a is configured to blow cool air from the upper left side of the tray 110 in a direction toward the tray 110, the second fan 130b is configured to blow cool air from the upper center of the tray 110 in a direction toward the tray 110, and the third fan 130c can be configured to blow cool air from the upper right side of the tray 110 in a direction toward the tray 110. However, this disclosure is not limited thereto, and the direction of airflow from each fan can vary depending on the fan mounting position.

[0075] According to an embodiment, the temperature controller TC can be a device for controlling the heat generated during the charging / discharging process of a secondary battery. The temperature controller TC can be software-driven to control the heating unit 120 and the cooling units 130a, 130b, 130c to maintain the temperature of the secondary battery at a user-set temperature. The temperature controller TC can control the temperature variation of the secondary battery to be relatively small during charging / discharging, thereby improving the performance and lifespan characteristics of the secondary battery.

[0076] Temperature sensor 140 can measure the temperature of the secondary battery during the charging / discharging process. According to an embodiment, temperature sensor 140 can be connected to a first probe 152a or a second probe 152b of the charging / discharging unit 150, such as... Figure 1As shown in the diagram. Therefore, when probes 152a and 152b descend or tray 110 rises to bring probes 152a and 152b into contact with the terminals of the secondary battery, temperature sensor 140 connected to probes 152a and 152b can measure the temperature by directly contacting the surface or interior of the secondary battery. When measuring the temperature by directly contacting the surface or interior of the secondary battery, the accurate temperature of the surface or interior of the secondary battery can be measured precisely. However, the temperature measurement method of temperature sensor 140 is not limited to this; temperature sensor 140 can also be a non-contact sensor.

[0077] In an embodiment, the vacuum tube 160 may contact or connect to the electrolyte inlet of the secondary battery to remove gas from inside the secondary battery. The interior of the vacuum tube 160 may be under negative pressure to maximize the removal of gas generated inside the secondary battery during the charging / discharging process. The vacuum tube 160 may be positioned where it can be easily connected to the electrolyte inlet of the secondary battery. For example, as... Figure 1 As shown, the vacuum tube 160 can be disposed between the first probe 152a and the second probe 152b, with the first probe 152a and the second probe 152b positioned where they can be easily connected to the terminals of the secondary battery (e.g., above the terminals). The vacuum tube 160 can be directly connected to the probes 152a and 152b of the charging / discharging unit 150. Alternatively, the vacuum tube 160 can be indirectly connected to the probes 152a and 152b of the charging / discharging unit 150 via the controller 170.

[0078] In an embodiment, the vacuum tube 160 may further include a reflux electrolyte storage section for temporarily collecting electrolyte that flows back through the electrolyte inlet during the repeated vacuum and venting processes performed in the degassing step. The electrolyte that has already flowed back during the vacuum period is stored in this storage section, and during the venting step, the electrolyte is reinjected into the electrolyte inlet through a return path, thereby preventing electrolyte loss. This configuration can maintain electrolyte stability inside the secondary battery even during the repeated vacuum and venting processes during the charging and settling steps, and as... Figure 3 As shown, gas removal through vacuum tube 160 and re-injection of refluxed electrolyte can be performed in parallel in a total of 12 steps, including charging and settling.

[0079] In this embodiment, the controller 170 can control the charging / discharging unit 150 to charge the secondary battery at a C-rate of 0.2C to 1.2C until the state of charge (SOC) of the secondary battery reaches a predetermined termination capacity (%) from 0% (or the initial state of the secondary battery before charging). Simultaneously, the controller 170 can control the temperature controller TC to maintain the temperature of the secondary battery, as measured by the temperature sensor 140, within a set temperature range during the charging period until the SOC reaches the termination capacity from 0%. At the same time, the controller 170 can control the vacuum tube so that it remains under negative pressure throughout the charging period until the SOC reaches the termination capacity from 0%. This allows for the continuous removal of gases generated inside the secondary battery during charging, particularly during the SOC charging phase.

[0080] The set temperature range described here can be 35°C to 65°C. Alternatively, the set temperature range can be 35°C to 45°C, 40°C to 50°C, 45°C to 55°C, 50°C to 60°C, or 55°C to 65°C. However, the set temperature range is not limited to these and can be changed according to the design and the surrounding environment.

[0081] The termination capacity (%) described here can be from 40% to 90%. The user can pre-input any value within this range into the controller 170 as the termination capacity. In this case, the controller 170 can send a signal to the control system in the charging / discharging unit 150 to control charging, so that charging can proceed only to a predetermined specific termination capacity.

[0082] The range of termination capacity can vary depending on the electrode materials inside the secondary battery. For each electrode material, the amount of gas that may be generated during charging and discharging may differ. In the case of electrode materials that may generate a small amount of gas, the termination capacity can be set low because the amount of gas to be removed is small. Alternatively, in the case of electrode materials that undergo a large rate of thickness change during charging and discharging, the termination capacity can be set low to minimize the stress received by the electrodes. For example, in the case of a negative electrode material including silicon, which undergoes a large rate of thickness change during charging and discharging, the termination capacity can be set to approximately 80%.

[0083] In this embodiment, when the temperature of the secondary battery is within the set temperature range described herein, the controller 170 can control the charging / discharging unit 150 to start charging the secondary battery, and when the temperature of the secondary battery is less than the minimum value of the set temperature range, the controller 170 can activate the temperature controller TC to bring the temperature of the secondary battery to the minimum value, and then start charging the secondary battery.

[0084] Figure 2 This is a flowchart illustrating a formation method according to an embodiment of the present disclosure.

[0085] Figure 2 The flowcharts and descriptions herein are merely examples of this disclosure, and the scope of this disclosure is not limited thereto. Figure 2 The flowchart and description herein. For example, one or more steps can be added / changed / deleted from the flowchart and description herein, the order of one or more steps can be changed, and one or more steps can be executed simultaneously.

[0086] Reference Figure 2 The formation method (200) for a secondary battery according to the embodiment can begin with a preheating step (S220) to preheat the secondary battery. Alternatively, before the preheating step (S220), the formation method 200 can begin with a pre-aging step (S210), in which an electrolyte is injected into the secondary battery and the secondary battery is left as is. The electrolyte can be injected through the electrolyte injection port of the secondary battery, and the secondary battery can be left as is (or left to stand) for a predetermined period of time so that the electrodes and the separator can be sufficiently wetted by the electrolyte. Since the electrolyte fully penetrates into the electrode material, the pre-aging step (S210) can improve the contact between the electrode surface and the electrolyte.

[0087] The pre-aging step (S210) can be carried out in a low temperature range of about 20°C to 30°C to slowly advance the internal reaction of the secondary battery. However, the pre-aging temperature is not limited to this and can be varied depending on the design of the secondary battery manufacturing method or the desired performance. For example, the pre-aging step can be carried out at less than or equal to 15°C under specific conditions.

[0088] In the preheating step (S220), the secondary battery can be preheated until its temperature reaches the set temperature range described herein, for example, 35°C to 65°C. The secondary battery can be preheated to a specific temperature before charging to ensure temperature uniformity. Furthermore, preheating can activate the electrode active materials inside the secondary battery and reduce thermal shock that may occur during charging. This can reduce the increase in stress and volume changes that may occur during the initial charge. The preheating step (S220) can be performed in conjunction with a reference... Figure 1 The formation process (hereinafter referred to as the formation apparatus) is performed in a separate preheating chamber. (See below for reference.) Figure 5 Describe the specific preheating method.

[0089] Next, the step of transferring the secondary battery to the formation apparatus (S230) can be performed. In the transfer step (S230), the tray, which has already been preheated in the preheating step (S220), can be transferred as is to improve process efficiency. In an embodiment, the transfer step (S230) can be performed by an automated transfer system to transfer the tray to the formation apparatus. The automated transfer system can be operated using devices such as conveyor belts, robotic arms, or AGVs (Automated Guided Vehicles).

[0090] During the transfer step (S230), the transfer path and environment can be maintained to keep temperature, humidity, and other conditions constant, ensuring that the temperature of the secondary batteries in the tray does not fluctuate. For example, the temperature of the secondary batteries in the tray can be continuously monitored by temperature sensors and a monitoring system in the transfer section, allowing for immediate action if a temperature fluctuation is detected.

[0091] The conveyed pallets can be precisely loaded into the tanks or support systems of the formation unit. For example, the conveying and loading of pallets can be performed by an automated loading system while minimizing vibration and shock to the secondary batteries, thus preventing damage to them.

[0092] Then, the charging step (S240), the temperature control step (S250), and the degassing step (S260) can be executed in parallel.

[0093] The charging step (S240) may include charging the secondary battery at a C-rate of 0.2C to 1.2C until the state of charge (SOC) of the secondary battery reaches a predetermined termination capacity (%) from 0%. According to an embodiment, the charging step (S240) may include the following steps: charging the secondary battery once at a specific C-rate within the C-rate range described herein, or charging the secondary battery multiple times at different C-rates within the C-rate range described herein. In this case, the termination capacity may be from 40% to 90%.

[0094] In the charging step (S240), charging of the secondary battery begins when the temperature of the secondary battery is within the set temperature range described here (e.g., 35°C to 65°C), and when the temperature of the secondary battery is less than the minimum value of the set temperature range, charging of the secondary battery can begin after heating the secondary battery to reach the minimum value.

[0095] The temperature control step (S250) may include maintaining the secondary battery within a set temperature range (e.g., 35°C to 65°C) as described herein until the secondary battery's state of charge (SOC) reaches a termination capacity (%) from 0%. At this point, the termination capacity may be between 40% and 90%. (See reference herein.) Figure 1As described, heating can be performed by heating the tray on which the secondary battery is mounted, and cooling can be performed by blowing cold air toward the tray.

[0096] The degassing step (S260) is a step to remove gas from inside the secondary battery, and it can be performed throughout the entire charging period from 0% SOC to when the SOC reaches its final capacity. This allows gases generated at high temperatures during the charging process to be removed as soon as they are generated, maximizing gas removal. In the degassing step (S260), by using a vacuum tube (e.g., Figure 1 The vacuum tube (160) contacts the electrolyte injection port of the secondary battery to remove gas from inside the secondary battery, and the inside of the vacuum tube can be kept under negative pressure. Throughout the entire charging period from when the secondary battery's SOC is 0% to when the SOC reaches its final capacity, the inside of the vacuum tube can be kept under negative pressure.

[0097] After the degassing step (S260), a step (S270) can be performed to release the vacuum tube from the electrolyte injection port of the secondary battery and seal the electrolyte injection port. Alternatively, welding, heat sealing, or bonding can be used as methods for sealing the electrolyte injection port. Or, a separate sealing member can be used. For example, a process can be performed to seal the electrolyte injection port with a pin-type plug. However, the plug used to seal the electrolyte injection port is not limited to this; for example, a ball-shaped plug can be used.

[0098] Figure 3 This is a charging recipe table showing the charging process performed step by step in a formation apparatus according to an embodiment of the present disclosure.

[0099] Figure 3 This is a table illustrating examples of the operation of a vacuum tube performed in a formation apparatus according to an embodiment. In this embodiment, here, Figure 1 The vacuum tube described in the document (e.g., Figure 1 160 in the formula may also include a reflux electrolyte storage section (hereinafter referred to as the "storage section") for preventing and storing electrolyte reflux that occurs internally during the degassing step while internal gases are removed through the electrolyte inlet in contact with the secondary battery.

[0100] In this embodiment, the degassing step is performed in parallel with the charging step and the temperature control step, and in this embodiment, as... Figure 3As shown, vacuuming and venting can be repeated during the charging step (“Charging”) and the resting step (“Resting”). The “Mode” in the recipe table indicates either a charging step or a resting step, and specifically refers to “Charging” and “Resting”, respectively. “Current (C-rate)” indicates the rate of charge current (C-rate), and C-rate refers to the ratio of the charge current to the battery's rated capacity (e.g., 0.2C means charging at 20% of the rated capacity). Additionally, “Volts [mV]” indicates the set value of the charging voltage. “Time [minutes]” indicates the duration of this step, in minutes. In the table, “Lower Vacuum Limit,” “Vacuum Value,” and “Upper Vacuum Limit” are the vacuum pressure values ​​(in kPa) set in the vacuum tube according to the steps, and can be controlled by the controller (e.g., Figure 1 The vacuum is maintained based on these values ​​under the control of (170). Here, "lower vacuum limit" is the lower reference pressure at the start of vacuum operation, and "upper vacuum limit" is the upper reference pressure during vacuum operation. "Vacuum value" indicates the target vacuum holding pressure. In the table, "[Vacuum] Vacuum holding time" is the time to maintain the vacuum value in seconds, and "[Exhaust] Leakage holding time" indicates the stabilization time after the vacuum is released during the exhaust step, also shown in seconds.

[0101] In this embodiment, the vacuum tube can maintain the set vacuum conditions step by step during the vacuum holding time, and then perform vacuum release in the venting step. In this example, the electrolyte that flows back through the electrolyte injection port during the vacuum process is temporarily collected in the return electrolyte storage section, and then the electrolyte can be re-injected (reflowed) into the electrolyte injection port through the re-injection tube in the venting step.

[0102] This structure prevents electrolyte loss even during repeated vacuuming and / or venting processes and ensures the stability of the internal electrolyte in the secondary battery. In embodiments, the vacuuming and reflow electrolyte re-injection can be repeated in a total of 12 steps (steps 1 to 12) covering both the charging and resting phases. More specifically, as Figure 3 As shown, a vacuum holding time and an venting (leakage) holding time are set for each step, and after maintaining the set vacuum value during the vacuum period, the refluxed electrolyte is collected into a storage unit through the venting step, and then it can be re-injected. However, this disclosure is not limited to this, and the vacuum and venting processes can also be performed using only a vacuum tube without a storage unit. For example, if the refluxed electrolyte can fall through a structure or internal path in the vacuum tube or return naturally, the refluxed electrolyte can be re-injected in the venting step without a separate storage unit.

[0103] Figure 4 It is a time-voltage curve used to illustrate the operation method of the formation apparatus and the formation method according to embodiments of the present disclosure. Figure 4 It is used for illustration and reference. Figure 2 The graphs showing the voltage, state of charge, and C-rate in the pre-aging step (S210), preheating step (S220), charging step (S240), and sealing step (S270) of the formation method for secondary batteries described herein.

[0104] The pre-aging step (S210) according to the embodiment can be performed at room temperature for approximately 12 to 48 hours. Afterwards, a preheating step (S220) can be performed by loading the secondary battery onto a tray. After the preheating step (S220) is completed, the seal of the secondary battery can be removed (S_R). In the seal removal step (S_R) for initiating charging of the secondary battery, the voltage can be 0V and the state of charge (SOC) can be 0%. The seal removal step (S_R) can be a step used to initiate a degassing step by contacting a vacuum tube with the electrolyte injection port.

[0105] In the charging step (S240) according to the embodiment, the secondary battery can be charged within a voltage range of 0.1V to 4.5V.

[0106] Furthermore, in the charging step (S240) until the secondary battery's SOC reaches a predetermined termination capacity (%) from 0%, the secondary battery can be charged at a C-rate of 0.2C to 1.2C. Here, the predetermined termination capacity (SOC of B%) can be 40% to 90%.

[0107] The charging step (S240) according to the embodiment may include charging the secondary battery once at a specific C-rate or charging the secondary battery multiple times at different C-rates. For example, refer to... Figure 4 The charging step (S240) can be performed in the order of step (C1) (charging at a C-rate of 0.2C to 0.5C for a predetermined time) and step (C2) (charging at a C-rate of 0.5C to 1.2C for a predetermined time). However, the C-rate of each charging segment and the number of charging segments are not limited thereto, and the secondary battery can be charged several times at different C-rates within the range of 0.2C to 1.2C.

[0108] The SOC range or termination capacity of a specific step during a predetermined time period of charging at a specific C-rate (e.g., SOC of A%, SOC of B%, etc.) can vary depending on the design of the secondary battery, such as the electrode material, capacity, and degree of heat generation.

[0109] In the charging step (S240) according to the embodiment, when charging is performed at a C-rate of 0.2C to 1.2C, and at a high C-rate of 1.2C to achieve the maximum C-rate, the mechanical or electrochemical stress received by the electrode can be reduced. Therefore, a stable film can be formed on the electrode surface, and a secondary battery with a stable structure can be manufactured.

[0110] Specifically, compared to a formation method that divides a pre-charge section for additive decomposition reactions inside the secondary battery, performed at a very low rate (e.g., 0.05C to 0.2C) in a low voltage region (e.g., less than or equal to 3.4V), and a charging section for film formation on the electrode surface, charged in a voltage range of, for example, 3.4V to 4.3V, the charging step (S240) described herein replaces the pre-charge section and the charging section with a single step. Furthermore, because the charging is performed at a high temperature (e.g., 35°C to 65°C) at a high rate of up to 1.2C in this step, gases inside the secondary battery can be generated and removed more effectively, and films on the electrode surface can be formed more densely.

[0111] The membrane can comprise a solid electrolyte interphase (SEI) layer formed on the negative electrode surface during the initial charging of the secondary battery, or a positive electrode electrolyte interphase (CEI) layer formed on the positive electrode surface. The SEI layer allows ions originating from the positive electrode to move easily, but reduces gas generation by preventing further decomposition of the electrolyte. The SEI layer maintains electrode stability by controlling ionic reactions on the negative electrode surface. The CEI layer is generated by side reactions between the electrolyte and the positive electrode, and particularly during the high-voltage operation of the secondary battery, it inhibits further decomposition of the electrolyte on the positive electrode surface, thereby ensuring long-term battery stability at high voltages and ensuring improved performance by preventing electrode capacity degradation.

[0112] When charged at a high rate (e.g., 0.2C to 1.2C) for a single charge, the stress on the electrodes is reduced compared to charging and discharging at a low rate (e.g., 0.05C to 0.2C) for an extended period, and the generation of inherent gas can be maximized. In this case, the extent to which a large amount of persistent gas is generated during the use steps following the manufacture of a secondary battery including electrodes that have already undergone a high-rate charge is reduced, and the performance of the secondary battery can be improved.

[0113] Figure 5 This is a schematic diagram of a tray according to an embodiment of the present disclosure. Figure 5 It is used for illustration and reference. Figure 1 The described tray and heating element, and references Figure 2 A diagram illustrating an example of the implementation of the described preheating step.

[0114] In one embodiment, the tray 110 on which a plurality of secondary batteries SB are mounted may include a heating plate 112 mounted on its lower part. However, this disclosure is not limited thereto, and any construction capable of uniformly heating the secondary batteries SB loaded therein may be used as the heating plate 112. For example, the heating plate 112 may be constructed in such a way that heating wires are arranged on the entire surface in contact with the secondary batteries SB.

[0115] As another example, the heating element 120 may be disposed separately in the peripheral portion of the tray 110 to uniformly heat the loaded secondary battery. For example, the heating element 120 may be disposed on at least one of the side surface or the lower surface of the tray 110 to uniformly heat the loaded secondary battery. However, this disclosure is not limited thereto, and various configurations for heating the secondary battery may be employed.

[0116] By reference Figure 1 The temperature controller described is used for temperature control and reference. Figure 2 The temperature control in the described temperature control step (S250) can be performed by increasing the temperature of the heating plate 112.

[0117] In reference Figure 2 In the described preheating step (S220), the temperature of the secondary battery SB, which has undergone the pre-aging step, is raised to a predetermined temperature by mounting a preheater 410 on a tray 110. When the temperature of the secondary battery SB reaches the predetermined temperature (e.g., 35°C to 65°C), the connection between the tray 110 and the preheater 410 can be released. (Refer to...) Figure 5 In one embodiment, a tray 110 may hold four rows (1R, 2R, 3R, 4R) of secondary batteries SB, and multiple trays 110 may be stacked and connected to a single preheater 410 for a preheating step.

[0118] and Figure 5 Unlike the previous version, the preheater 410 includes a preheating chamber, and a tray 110 on which a secondary battery SB is loaded is placed into the preheating chamber so that the secondary battery SB can be uniformly preheated for a predetermined period of time. The preheating steps according to the embodiment can be performed in the following sequence: stacking the tray 110 on which the secondary battery SB is loaded and placing the tray 110 into the preheater 410; connecting the connector of the tray 110 to the heating element of the preheater 410; preheating the tray to a predetermined specific temperature within a temperature range of 35°C to 65°C; and releasing the connection between the connector and the heating element when preheating is complete.

[0119] The preheating step described herein can improve the speed of the formation process by raising the temperature to a predetermined high temperature (e.g., 35°C to 65°C) before transferring and placing the secondary battery into the formation apparatus.

[0120] Figure 6 It is a graph showing the results of evaluating the internal pressure changes of a secondary battery that has undergone formation.

[0121] In the following description, the formation method according to the first example can be performed in the following order: injecting electrolyte into a prismatic secondary battery and loading the secondary battery onto a tray; performing pre-aging and then transferring the tray to a charging / discharging facility; charging / discharging the secondary battery in the charging / discharging facility; transferring the tray to an aging chamber and keeping the tray as is; removing gas from the secondary battery; and sealing the electrolyte injection port.

[0122] The formation method according to the second example can be performed by the formation apparatus and formation method described herein. Hereinafter, the formation method according to the second example can be performed in the following order: injecting electrolyte into a prismatic secondary cell and loading the secondary cell onto a tray; performing pre-aging and then heating the secondary cell in a preheater; transferring the tray to a reference... Figure 1 The steps of the formation apparatus described; the steps of operating a heating plate mounted on the lower part of the tray and a fan mounted on the upper part of the tray to maintain the secondary battery within the set temperature range described herein while charging / discharging the secondary battery; the steps of contacting the vacuum tube with the electrolyte injection port to remove gas; and the steps of sealing the electrolyte injection port.

[0123] exist Figure 6 In the graph, the x-axis indicates the number of days (days) the secondary battery has been used (charge / discharge) after formation, and the y-axis indicates the result of measuring the internal pressure of the secondary battery using a pressure sensor. The conditions used to evaluate the internal pressure of the secondary battery are the CC / CV charging method, in which a full charge voltage of 4.3V is used, and charging is performed at a C-rate of 0.2C. Initially, charging is performed with a constant current, and once 4.3V is reached, charging is performed with a constant voltage. Additionally, the secondary battery is discharged to 2.8V, and a 10-minute resting period is set between charging and discharging to stabilize the reactions occurring inside the battery.

[0124] Reference Figure 6It was confirmed that the internal pressure of the secondary battery that had undergone the formation method according to the second example 520 was lower than that of the secondary battery that had undergone the formation method according to the first example 510. This indicates that, compared to the first example, the amount of gas generated by the side reactions inside the secondary battery was smaller in the secondary battery that had undergone the formation method according to the second example. As a result of analyzing the composition of the gas generated inside the secondary battery sample after 5 days, it was confirmed that the gas included carbon dioxide (CO2), methane (CH4), carbon monoxide (CO), and ethane (C2H6), and that the gas was generated at a concentration of about 16,000 ppm in the first example and about 10,000 ppm in the second example.

[0125] Figure 7 It is a graph showing the results of evaluating the thickness change of a secondary battery that has undergone formation.

[0126] exist Figure 7 In the graph, the x-axis indicates the elapsed usage time (in hours) of the formed secondary battery (charge / discharge), and the y-axis indicates the result of measuring the thickness (mm) of the secondary battery during the charging and discharging process. Besides evaluating the secondary battery at 60°C without pressing it, the conditions used to evaluate the thickness of the secondary battery are the same as... Figure 6 The conditions described in the text are the same.

[0127] Reference Figure 7 It was confirmed that the secondary cell that had undergone the formation methods according to the second examples 620a and 620b was thinner than the secondary cell that had undergone the formation methods according to the first examples 610a and 610b. This is believed to be because fewer side reactions occurred inside the secondary cell.

[0128] Figure 8 This is an XPS curve showing the surface analysis results of the positive electrode material of the secondary battery. Figure 8 The graph shows the results of analyzing the composition of the cathode surface of a secondary battery that has undergone formation by means of XPS (X-ray photoelectron spectroscopy) analysis based on the intensity analysis of the binding energy (eV). For evaluation, NCA (nickel-cobalt-aluminum oxide, LiNi) was used as a high-nickel ternary cathode material. 0.8 Co 0.1 Al0 .1 O2).

[0129] Reference Figure 8In both the first and second examples, NCA-O and Li2CO3 peaks appeared. The NCA-O peak refers to the peak of NCA in its oxide state. Lithium carbonate (Li2CO3) is a byproduct generated on the cathode surface when lithium ions react with the electrolyte and may affect film formation. As a result of analyzing the Li2CO3 peak area, it was confirmed that the amount of lithium carbonate in the second example 720 was reduced by approximately 9% compared to the first example 710. This indicates that the secondary battery that has undergone the formation method according to the second example 720 has a thinner lithium carbonate and organic / inorganic side reaction layer compared to the secondary battery that has undergone the formation method according to the first example 710. This is believed to be because the film formation reaction consuming electrolyte was reduced in the second example.

[0130] Figure 9 This is a graph showing the results of evaluating the crystal structure of the cathode material of a secondary battery using Raman spectroscopy. Figure 9 The graph shows the results of Raman spectroscopy based on Raman shift (cm). -1 The results of spectral analysis were used to analyze the positive electrode crystal structure of the secondary battery that had undergone formation. NCA was used as the positive electrode for evaluation.

[0131] Reference Figure 9 Compared to the first example 810, the second example 820 is more clearly visible at approximately 600 cm. -1 A appears at the location 1g (Ni) vibrational mode peak. This indicates that the layered structure of NCA was better preserved in the second example 820 compared to the first example 810, and less rock salt structure formation was observed. A secondary cell including a cathode with numerous rock salt structures refers to a secondary cell that has deteriorated and become irreversibly incapable of further reaction. (Refer to...) Figure 9 It was confirmed that the rock salt structure was less in the second example 820 than in the first example 810, which indicates that the internal resistance of the secondary battery is further reduced in the second example 820 and that the secondary battery is of excellent performance.

[0132] Figure 10 This is a graph showing the XRD analysis results of the positive electrode material of a secondary battery. Figure 10 The graph shows the results of analyzing the atomic-scale crystal structure of the cathode of a secondary battery that has undergone formation using X-ray diffraction analysis based on spectral analysis at the diffraction angle (2θ). NCA was used as the cathode for evaluation.

[0133] Reference Figure 10Initial state example 900 shows the results of analyzing the positive electrode of a secondary battery that has not undergone formation, and first example 910 and second example 920 show the results of analyzing the positive electrode of a secondary battery from the initial state using the formation method described herein. Compared to first example 910, the (003) peak indicating NCA appears on the right side in second example 920, confirming that charging has been carried out slightly more. This refers to the fact that the negative electrode potential in second example 920 is higher than that in first example 910. This confirms that second example 920 is superior in charge / discharge efficiency due to reduced lithium-ion consumption side reactions (such as lithium deposition at the negative electrode) compared to first example 910.

[0134] Figure 11 This is a graph showing the results of evaluating the lifetime characteristics of a secondary battery that has undergone charging and discharging. Figure 12 This is a graph showing the results of evaluating the internal resistance based on the charge and discharge life of a secondary battery that has already undergone formation. Figure 11 It is a graph showing the results of evaluating capacity retention by repeating charge and discharge cycles with one charge and one discharge as a cycle. Figure 12 This is a graph showing the results of evaluating the DC internal resistance (DC-IR) in a specific cycle. Figure 12 It is a graph showing the percentage increase in internal resistance as a result of charge / discharge cycles, with the initial internal resistance set to 100%.

[0135] The secondary battery formed using the method was evaluated at 45°C, with charging and discharging performed at a C-rate of 0.5C within a voltage range of 2.8V to 4.3V.

[0136] Reference Figure 11 This confirms that, compared to the secondary battery using the formation method according to the first example 1010, the capacity retention rate is higher in the secondary battery using the formation method according to the second example 1020, reaching up to approximately 580 cycles. (Refer to...) Figure 12 This confirms that, compared to a secondary battery using the formation method according to the first example 1110, the internal resistance is lower in a secondary battery using the formation method according to the second example 1120 at up to approximately 580 cycles.

[0137] Figure 13 This is a graph showing the results of evaluating the capacity based on the storage time of a secondary battery that has undergone formation. Figure 14 This is a graph showing the results of evaluating the internal resistance based on the storage time of a secondary battery that has undergone formation. Figure 13 The graph shows the results of evaluating capacity retention based on storage time (days) by placing a converted secondary battery in a constant temperature chamber at 60°C. Figure 14This is a graph showing the results of evaluating the change in internal resistance over storage time (days) by placing a formed secondary battery in a constant temperature chamber at 60°C. Figure 13 The evaluation criteria are the same.

[0138] Reference Figure 13 This confirms that the capacity retention rate of the secondary battery using the formation method according to the second example 1220 is at a similar level to that of the secondary battery using the formation method according to the first example 1210, reaching up to approximately 95 days. (Refer to...) Figure 14 This confirms that the internal resistance in the secondary battery using the formation method according to the second example 1320 is at a similar level to that in the secondary battery using the formation method according to the first example 1310, up to about 95 days.

[0139] This indicates that even though the secondary battery has undergone formation at high temperature and high rate, the secondary battery that has undergone formation according to the second example is superior to the secondary battery that has undergone formation according to the first example in terms of lifetime characteristics and performance in terms of charge / discharge and storage, or is at a similar level to the secondary battery that has undergone formation according to the first example.

[0140] Although embodiments of this disclosure have been described herein, this disclosure is not limited thereto. Various modifications and variations can be made by those skilled in the art within the spirit of this disclosure and the equivalents of the appended claims.

Claims

1. A formation apparatus for a secondary battery, the formation apparatus for a secondary battery comprising: A temperature controller is used to control the temperature of the secondary battery; A temperature sensor is used to measure the temperature of the secondary battery; A charging / discharging unit, including probes that contact the terminals of the secondary battery; A vacuum tube is used to remove gas from inside the secondary battery. as well as A controller is provided for charging the secondary battery until the secondary battery reaches its final state of charge (SOC) capacity. The controller controls the temperature controller to maintain the temperature of the secondary battery, as measured by the temperature sensor, within a set temperature range during charging, and also controls the vacuum tube during charging. The termination capacity is 40% to 90%.

2. The formation apparatus for secondary batteries according to claim 1, wherein, The temperature range is 35°C to 65°C.

3. The formation apparatus for secondary batteries according to claim 1, wherein, The secondary battery is mounted on a tray, and the temperature controller includes a heating element for heating the tray.

4. The formation apparatus for secondary batteries according to claim 3, wherein, The temperature controller includes a fan for blowing cool air toward the tray.

5. The formation apparatus for a secondary battery according to claim 1, wherein, The probe includes a first probe and a second probe. The first probe is electrically connected to a first terminal of a first electrode of the secondary battery, and the second probe is electrically connected to a second terminal of a second electrode of the secondary battery. The temperature sensor is connected to either the first probe or the second probe, and the vacuum tube is in contact with the electrolyte injection port of the secondary battery.

6. The formation apparatus for a secondary battery according to claim 1, wherein, The inside of the vacuum tube is under negative pressure.

7. The formation apparatus for a secondary battery according to claim 1, wherein, The controller controls the charging / discharging unit to charge the secondary battery at a C-rate of 0.2C to 1.2C until the state of charge of the secondary battery reaches the termination capacity.

8. The formation apparatus for a secondary battery according to claim 1, wherein, The controller controls the charging / discharging unit to charge the secondary battery multiple times at different C-rates during charging.

9. A formation method for a secondary battery, the formation method for a secondary battery comprising the following steps: The preheating step preheats the secondary battery; The charging step involves charging the secondary battery until the state of charge of the secondary battery reaches its termination capacity. The temperature control step maintains the secondary battery within a set temperature range until the state of charge of the secondary battery reaches the termination capacity. as well as The degassing step removes the gas inside the secondary battery. The charging step, the temperature control step, and the degassing step are performed in parallel, and the termination capacity is 40% to 90%.

10. The formation method for a secondary battery according to claim 9, wherein, The temperature range is 35°C to 65°C.

11. The formation method for a secondary battery according to claim 9, further comprising a pre-aging step of injecting electrolyte into the secondary battery and placing the secondary battery as is prior to the preheating step.

12. The formation method for a secondary battery according to claim 9, wherein, In the preheating step, the secondary battery is preheated until its temperature reaches 35°C to 65°C.

13. The formation method for a secondary battery according to claim 9, wherein, The preheating step includes: The steps of stacking trays loaded with the secondary batteries and placing the trays into the preheater; The steps of connecting the tray to the heating section of the preheater; and The step of preheating the tray to a predetermined specific temperature between 35°C and 65°C.

14. The formation method for a secondary battery according to claim 9, wherein, During the charging step, the secondary battery is charged within a voltage range of 0.1V to 4.5V.

15. The formation method for a secondary battery according to claim 9, wherein, In the temperature control step, heating is performed by heating the tray containing the secondary battery, and cooling is performed by blowing cold air toward the tray.

16. The formation method for a secondary battery according to claim 15, wherein, The tray includes a heating plate mounted on its lower part, and the temperature control step is performed by increasing the temperature of the heating plate.

17. The formation method for a secondary battery according to claim 9, wherein, In the degassing step, the gas inside the secondary battery is removed by bringing the vacuum tube into contact with the electrolyte injection port of the secondary battery, and the inside of the vacuum tube is under negative pressure.

18. The formation method for a secondary battery according to claim 17, further comprising the steps of releasing the vacuum tube from the electrolyte injection port and sealing the electrolyte injection port after the degassing step.

19. The formation method for a secondary battery according to claim 9, further comprising the step of transferring the secondary battery to a formation apparatus between the preheating step and the charging step.

20. The formation method for a secondary battery according to claim 9, wherein, In the charging step, the secondary battery is charged multiple times at different C-rates ranging from 0.2C to 1.2C until the state of charge of the secondary battery reaches the termination capacity.

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