Method for separating secondary battery cell

Abstract

The present invention relates to a method for separating a secondary battery cell in which components of a battery cell are separated and are each recycled. The present invention provides a method for separating a secondary battery cell, comprising a cell supply step, a casing separation step, a first heat treatment step, and an electrode separation step. In addition, the present invention provides a method for separating a secondary battery cell, comprising an opening step, a frame separation step, and an electrode separation step. According to the present invention, the components of a battery cell can be separated and each recycled, an electrolyte can be evaporated in a state in which a separator is present, thereby preventing the occurrence of fire during the separation process, and a positive electrode and a negative electrode can be separated and recycled, thereby increasing the recovery rate and reducing recovery costs.

Description

Secondary battery cell separation method

[0001] The present invention relates to a method for separating secondary battery cells, and to a method for separating battery cells by separating the components of the battery cells and recycling each component.

[0002] With the recent rapid growth of the electric vehicle market, the electric vehicle battery market is also growing rapidly. This surge in battery demand is expected to lead to a large volume of waste batteries generated as they reach the end of their lifespan.

[0003] Accordingly, the market for recycling used batteries is growing, and technologies for processing them are also advancing. Methods for recycling used batteries include utilizing them as reusable Energy Storage Systems (ESS), and recycling used batteries that are unsuitable for reuse or have already been reused.

[0004] Recycling waste batteries involves extracting valuable metals like nickel and cobalt through processes such as disassembly, mechanical crushing, and chemical treatment. However, mechanical crushing poses a fire risk due to the high reactivity of lithium ions. Furthermore, the resulting powder is also flammable, making storage difficult. Furthermore, if the entire waste battery is crushed, the subsequent chemical treatment to extract valuable elements is complex and expensive.

[0005] Prior art literature

[0006] Prior Document 1: Republic of Korea Patent No. 10-2414319 (registered on June 24, 2022)

[0007] Prior Document 2: Republic of Korea Patent No. 10-2317034 (registered on October 19, 2021)

[0008]

[0009] The technical purpose of the present invention is to separate the configuration of a battery cell and recycle each configuration separately.

[0010] Another technical object of the present invention is to prevent fire from occurring during the separation process by evaporating the electrolyte while a separator is present.

[0011] Another technical object of the present invention is to increase the recovery rate and reduce the recovery cost by separating and recycling the anode and cathode.

[0012] Another technical object of the present invention is to remove environmentally harmful elements without burning the membrane, reduce the cost of removing hazardous substances, and enable recycling of the membrane itself.

[0013]

[0014] The present invention provides a method for separating a secondary battery cell, including steps of cell supply, casing separation, first heat treatment, and electrode separation.

[0015] In addition, a method for separating a secondary battery cell including a cell supply step, an opening step, a first heat treatment step, a frame separation step, and an electrode separation step is provided.

[0016]

[0017] According to the present invention, the configuration of the battery cell can be separated and recycled individually.

[0018] Additionally, by evaporating the electrolyte while the separator is present, fire can be prevented during the separation process.

[0019] Additionally, by separating the positive and negative electrodes and recycling them, the recovery rate can be increased and the recovery cost can be reduced.

[0020] Additionally, it removes environmental hazards without burning the membrane, reduces the cost of removing hazardous substances, and allows the membrane itself to be recycled.

[0021]

[0022] Figure 1 is a flowchart of a secondary battery cell separation method.

[0023] Figure 2 is a drawing showing a module disassembly step for disassembling a battery module into battery cells.

[0024] Figure 3 is a drawing showing a part of the casing being cut in the casing separation step.

[0025] Figure 4 is a drawing showing the process of vaporizing an electrolyte through heat treatment and capturing it in an electrolyte collector.

[0026] Figure 5 is a drawing showing the combined shape of the positive electrode, negative electrode, and separator of a battery having multiple separators and the sequential separation thereof.

[0027] Figure 6 is a drawing showing the combined shape of the positive and negative separators of a battery with one separator.

[0028] Figure 7 is a drawing showing the process of cutting a separator in the electrode separation step.

[0029] Figure 8 is a drawing showing the process of the first heat treatment step and the electrode separation step.

[0030] Figure 9 is a drawing showing that the separator is removed and the positive and negative electrodes are separated and crushed.

[0031] Figure 10 is a flowchart of a secondary battery cell separation method including a cooling step.

[0032] Figure 11 is a drawing showing the appearance of a battery module.

[0033] Figure 12 is a perspective view of the battery module with the cover removed.

[0034] Figure 13 is a plan view showing the appearance of cutting a connecting electrode.

[0035] Figure 14 is a drawing showing the internal structure of a secondary battery cell.

[0036] Figure 15 is a diagram showing the process of the opening stage.

[0037] Figure 16 is a drawing showing the process of vaporizing an electrolyte through heat treatment and capturing it in an electrolyte collector.

[0038] Figure 17 is a drawing showing the process of separating the cell assembly and the frame in the electrode separation step.

[0039] Figure 18 is a diagram showing a cell assembly collection step.

[0040] Figure 19 is a drawing showing two or more secondary battery cells undergoing an electrode separation step simultaneously.

[0041] Figure 20 is a flowchart of a method for separating a cylindrical secondary battery cell including a cooling step.

[0042]

[0043] The present invention provides a method for separating a battery cell including a cell assembly composed of a positive electrode, a negative electrode, an electrolyte, and a separator, the method comprising a first heat treatment step of heating the cell assembly to vaporize the electrolyte, and an electrode separation step of separating the positive electrode or the negative electrode from the separator.

[0044] In addition, a method for separating a battery cell including a cell assembly composed of a positive electrode, a negative electrode, an electrolyte, and a separator and a frame sealing the cell assembly is provided, the method including an opening step of opening a part of the frame, a first heat treatment step of heating the cell assembly to vaporize the electrolyte, and an electrode separation step of separating the positive electrode or the negative electrode from the separator.

[0045]

[0046] The purpose and effects of the present invention will become clearer through the detailed description below, but the purpose and effects of the present invention are not limited to the following description alone. Furthermore, in describing the present invention, if a detailed description of known technologies related to the present invention is deemed to unnecessarily obscure the gist of the invention, such detailed description will be omitted.

[0047] Hereinafter, with reference to the attached drawings, embodiments of the present invention will be described in detail so that a person skilled in the art can easily practice the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments disclosed below. In addition, in order to clearly disclose the present invention in the drawings, parts unrelated to the present invention are omitted, and the same or similar symbols in the drawings represent the same or similar components. FIGS. 1 to 10 relate to a method for separating a pouch-type secondary battery cell, and FIGS. 11 to 20 relate to a method for separating a cylindrical secondary battery cell. Referring to FIGS. 1 to 20, a method for separating a pouch-type secondary battery cell and a method for separating a cylindrical secondary battery cell will be sequentially described.

[0048] The method for separating a pouch-type battery cell (100) can be divided into a method using a discharged battery and a method using a non-discharged battery. However, both methods can separate the battery cell (100) through the same process, but when using a non-discharged battery, since no discharging is performed, the number of workers and space required for discharging can be maximized, and since a discharger is not used, the investment cost can be minimized, making it economical. Hereinafter, the common process of the method for separating a pouch-type battery cell (100) will be described.

[0049] Referring to FIG. 1, a method for separating a battery cell (100) is a method for separating a battery cell (100) including a positive electrode (111), a negative electrode (112), an electrolyte, and a separator (113), including a first heat treatment step (S400) of heating a cell assembly (110) to vaporize the electrolyte, an electrode separation step (S500) of separating the positive electrode (111) or the negative electrode (112) from the separator (113), and then performing crushing after separating each component of the battery cell (100). However, a cell supply step (S200) and a casing separation step (S300) may be further included before the first heat treatment.

[0050] The cell supply step (S200) is a step of supplying cells to the battery cell (100) separation line according to the present invention. Prior to the cell supply step (S200), a module disassembly step is performed to disassemble a module-based battery into cell units, so that the cells can be supplied to the battery cell (100) separation line in the form of cells.

[0051] The module disassembly step (S100) can be divided into a module disassembly step of a discharge module and a module disassembly step of a non-discharge module. Referring to Fig. 2, in the case of a discharge module, the module disassembly step (S100) can be performed by cutting the side of the module. At this time, the cutting can be performed using a module cutting device (310) that applies pressure, such as a press, to cut one side of the module. When cutting, both sides where the negative and positive electrodes (111) protrude can be cut simultaneously. Alternatively, by first cutting one side of either the negative electrode (112) or the positive electrode (111) and then cutting the remaining side, a short circuit can be prevented, so that even if a module is not completely discharged, it can be safely cut and disassembled.

[0052] By including the module disassembly step (S100) in this way, the battery in module or pack units is disassembled into cell units, thereby reducing the probability of occurrence of hazards such as fire or explosion compared to when all battery cells (100) are connected, and even if an accident such as fire or explosion occurs, the effect is that it is reduced to the size of one battery cell (100).

[0053] In the case of a zero-discharge module, the same method as the discharge module described above can be utilized. In addition, the module disassembly step of the zero-discharge module may further include a cooling step. The cooling step in the module disassembly step (S100) may be performed in the same manner as the cooling step of the cell separation method described later. Since moisture may condense and cause a short circuit, the cutting must be completed quickly after freezing is completed, and it is preferable to cut within 1 minute. In addition, if a cooling step is provided, a dry environment is required to prevent moisture condensation, and a dry environment can be created by using equipment capable of controlling the internal environment, such as a chamber, or by utilizing a moisture removal device or an inert gas such as nitrogen.

[0054] A battery cell (100) is configured to include a cell assembly (110) including a positive electrode (111), a negative electrode (112), an electrolyte, and a separator (113) inside, and a casing surrounding the cell assembly (110). The casing separation step (S300) is a step of separating the casing and the cell assembly (110).

[0055] The casing separation step (S300) is performed by cutting a portion of the casing, and may be performed by cutting one or more sides of the casing.

[0056] Referring to Fig. 3, it shows three vertically cut sections (120) of the casing surrounding the cell assembly (110). In this way, the cell assembly (110) can be separated through the cut sections by cutting the sections of the casing. However, as described above, it is possible to cut one section, and when only one section is cut, there is an advantage of increased process efficiency. In addition, rather than vertically cutting the section where the sections meet as shown in Fig. 3, it is also possible to cut perpendicularly to one section.

[0057] Including the casing separation step (S300) in this way allows the separately separated casing to be recycled as is or only the materials contained in the casing to be collected separately, so the separation step can be reduced compared to crushing the entire battery cell (100) and mixing all the recyclable materials, which is economical in terms of cost and time.

[0058] Meanwhile, the description is based on the casing separation step (S300) being performed before the first heat treatment step (S400), but if the first heat treatment step (S400) is performed without separating the casing, the casing can be separated after the first heat treatment step (S400).

[0059] At this time, if the first heat treatment step (S400) is performed without separating the casing, a hollow portion may be formed on a portion of the surface of the casing so that the electrolyte vaporizes and escapes through the hollow portion.

[0060] The first heat treatment step (S400) is a step of heating the cell assembly (110) to vaporize the electrolyte. That is, the cell assembly (110) including the positive electrode (111), negative electrode (112), electrolyte, and separator (113) remaining after separating the casing is heated to vaporize the electrolyte, and then the vaporized electrolyte is captured. That is, the first heat treatment step (S400) may be performed including a first heating step and a first electrolyte capture step.

[0061] Meanwhile, the first electrolyte capture step can be performed by capturing the vaporized electrolyte, transporting it to a relatively low-temperature space, allowing it to condense and then collect it as a liquid. Because the electrolyte emits a pungent odor when vaporized and is environmentally harmful, it is desirable to capture it by including the electrolyte capture step. Capturing the electrolyte through the aforementioned electrolyte capture step allows for recycling or easy disposal.

[0062] In the first heating step included in the first heat treatment step (S400), the cell assembly (110) can be heated by supplying heat to the cell assembly (110) using a heating device.

[0063] For example, a heating device may heat the cell assembly (110) by supplying hot air having a predetermined temperature range. In another example, the heating device may be provided as a device such as a chamber having an internal space, and the cell assembly (110) may be heated by increasing the internal temperature. In addition, various methods for heating the cell assembly (110) may be utilized.

[0064] In addition, in the first heating step, the temperature of the hot air applied to the cell assembly (110) or the temperature inside the chamber is preferably 90 to 180 degrees, and the time for which the temperature is applied to the cell assembly (110) and maintained is preferably formed to be about 20 minutes to 1 hour. Referring to FIG. 4, when heated by a heating device in the heating step, the electrolyte vaporizes and becomes a gas, and at this time, an electrolyte collector for collecting the gas can be provided to collect the vaporized electrolyte. When the electrolyte collector collects the electrolyte after vaporizing it to a predetermined ratio or more and then removing it from the cell assembly (110), the adhesive strength of the positive electrode (111), the negative electrode (112), and the separator (113) that were adhered to each other is weakened, making it easy to separate them. Referring to FIG. 8, it can be seen that only a portion of the electrolyte has vaporized by performing the first heating step. In this way, if only a portion of the electrolyte is vaporized and removed from the cell assembly (110), the adhesive strength of the positive electrode (111), negative electrode (112), and separator (113), which were adhered to each other, is weakened, making them easy to separate. On the other hand, if the electrolyte is excessively vaporized and removed in the first heat treatment step, the positive electrode (111) or negative electrode (112) may become excessively dry and fall off as powder, and may mix with each other, reducing the recovery rate. Therefore, it is preferable that the amount of the predetermined electrolyte that is vaporized and then collected in the first heat treatment step is 20 to 50% of the total electrolyte.

[0065] In addition, as the electrolyte is vaporized and removed through the first heating step, the separator (113) shrinks, and as the separator (113) shrinks, the positive electrode (111), the negative electrode (112), and the separator (113), which were fixed to each other, are easily separated from each other. Meanwhile, in order to enable the vaporized electrolyte to be captured without diffusing into another space, it is preferable to perform the first heat treatment step (S400) in a sealed space. The sealed space may be a chamber, a sealed container, or the like. In addition, the electrolyte can be recovered by including a process of cooling and condensing the electrolyte captured through the preceding process.

[0066] In this way, by including the first heat treatment step (S400), the electrolyte among the components of the cell assembly (110) can be evaporated and captured in a gaseous state. In addition, since the electrolyte is removed from the cell assembly (110), it becomes easy to separate the remaining components that were adhered to each other, and the separator (113) shrinks, so that the electrode and the separator (113) can be naturally separated. In addition, since the electrolyte is separated by evaporating only the electrolyte while the separator (113) is present, the positive electrode (111) and the negative electrode (112) do not come into contact, so that a short circuit does not occur, and thus a fire can be prevented. In addition, since the electrolyte is evaporated and removed, the electrolyte, which is an ion included in the electrolyte, cannot move, so that lithium does not move, thereby preventing a fire.

[0067] Additionally, a vaporization promotion step may be further provided after the first heat treatment step (S400) to promote vaporization of the electrolyte (114). The vaporization promotion step may utilize various methods capable of promoting vaporization of the electrolyte (114). However, in one embodiment of the present invention, a method of increasing the area exposed to the air of the electrolyte (114) to enable faster vaporization will be described.

[0068] The vaporization promotion step may be performed by bending the cell assembly (110) so that the surfaces of the positive electrode (111), the separator (113), and the negative electrode (112) of the cell assembly (110) that has previously undergone the first heat treatment step (S400) are more exposed. In other words, it may be performed in a manner similar to unfolding the pages of a book. In the cell assembly (110) unfolded in this manner, gaps are created between each component, and air can enter and exit through the gaps, thereby increasing the area of ​​the electrolyte (114) exposed to the air.

[0069] The electrode separation step (S500) is a step for separating the positive electrode (111) and the negative electrode (112) from the cell assembly (110) from which the electrolyte has been removed. The electrode separation step (S500) is a step for separating and crushing the negative electrode (112) and the positive electrode (111) separately so that they can be recycled, since the materials of the negative electrode (112) and the positive electrode (111) are different.

[0070] Meanwhile, the electrode separation step (S500) may be performed differently depending on two methods for forming the cell assembly (110). The two methods are described below. Referring to FIGS. 5 and 6, the cell assembly (110) may be formed in two ways.

[0071] Referring to FIG. 5, a cell assembly (110) can be formed by stacking multiple separators (113) so that one separator (113) is positioned between the positive electrode (111) and the negative electrode (112). In addition, referring to FIG. 6, a separator (113) can be formed so that the negative electrode (112) and the positive electrode (111) are inserted between the stacked separators (113) which are folded on both sides.

[0072] In the case of a pouch-type battery cell (100) that does not utilize a method of continuously stacking a separator (113) as shown in FIG. 5, it can be configured by only pulling and separating the electrode or separator. However, in the case of having a shape as shown in FIG. 6, the negative electrode (112) and the positive electrode (111) must be separated from both sides. Therefore, in order to separate the positive electrode (111) and the negative electrode (112) from one side, a separator cutting step may be additionally included to cut the separator (113) on one side.

[0073] The membrane cutting step may be performed before or after the first heat treatment, and may be performed by cutting one or both sides of the cell assembly (110). In addition, if the vaporization promotion step described above is included, it may be performed before the vaporization promotion step.

[0074] The membrane cutting step can be performed by making a predetermined number of long scratches on one side of the membrane (113) to be opened using a cutting device so that the membrane (113) can be opened. The cutting device can be equipped with a knife having a sharp blade, or can be equipped with a device capable of making scratches on the side of the membrane (113).

[0075] Meanwhile, as shown in Fig. 7, it is also possible to vertically cut one side of the folded side of the separator (113) to open it so that the electrode can be discharged through the cut side.

[0076] In addition, referring to FIG. 5, the electrode separation step (S500) can sequentially separate and remove the stacked positive electrode (111), separator (113), and negative electrode (112) from the upper side.

[0077] Also, referring to FIG. 8, the electrode separation step of separating the positive electrode (111) or the negative electrode (112) from the first separator (113) may be performed by having the separator (113) attached to the positive electrode (111) or the negative electrode (112) together. Alternatively, there may be a case where the separator (113) is attached to both sides of the positive electrode (111) and separated. The right-hand figure after the electrode separation sequentially from the top shows a drawing showing a case where the separator (113) is attached to the positive electrode (111) and separated together, a drawing showing a case where the separator (113) is attached to the negative electrode (112), and a case where the separator (113) is attached to both sides of the positive electrode (111) and separated.

[0078] In this way, by including the electrode separation step (S500), the cathode (112) and anode (111), which are made of different materials, can be separated and recycled separately. In addition, NCM, Al, Cu, Graphite, etc. can be reliably recovered at a rate of 98% or higher, and recovery costs can be drastically reduced.

[0079] Meanwhile, the positive electrode (111) or negative electrode (112) separated through the electrode separation step (S500) may have a separator (113) attached to it or residue of the separator (113) may remain. To separate this, a separator (113) separation step may be further included. The separator (113) separation step may be performed by crushing the separated positive electrode (111) and negative electrode (112) respectively and then separating the separator (113) through the difference in specific gravity. At this time, a method of putting it in water or blowing it with wind can be used as a separation method through the difference in specific gravity. When the crushed positive electrode (111) or negative electrode (112) is put in water, the separator (113) with a low specific gravity floats in the water, so it can be separated from the remaining materials. Alternatively, when blowing the wind, the separator (113) with a low specific gravity flies far, so this can be utilized for separation.

[0080] However, in the electrode separation step (S500), it is also possible to crush the positive electrode (111), negative electrode (112), and separator (113) together without separating them separately. In this case, it is also possible to separate the separator (113) using a method utilizing the above-described difference in specific gravity, and to proceed with the subsequent separation step while the positive electrode (111) and negative electrode (112) are crushed together. At this time, the positive electrode (111) and negative electrode (112), which have been stabilized through the first heat treatment step (S400), do not cause a fire even if they are crushed together.

[0081] In addition, after the electrode separation step (S500), a stabilization step of contacting water with the positive electrode (111) or the negative electrode (112) may be further included. The stabilization step is a step of contacting water with the positive electrode (111) or the negative electrode (112) or both separated through the electrode separation step (S500), and it is preferable to contact water by spraying it in the form of a mist. When the stabilization step is performed in this way, the water comes into contact with the lithium contained in the electrode and reacts, generating heat. However, since the mist is made of fine particles, it does not ignite but only generates heat. If it continues to contact the mist, the lithium gradually becomes stable thereafter. In addition, since the water used to spray the mist may react with the powder if it contains impurities and cause a fire, pure water (DI water) can be used, or it is preferable to use salt water containing 1 to 3% salt, alcohols such as ethanol, but water containing ions, etc. can also be used.

[0082] Meanwhile, if the first heat treatment step (S400) is performed under the condition of 120 degrees for less than 20 minutes, the separator can be separated while being attached only to the anode (111) side. Since the cathode (112) is formed of graphite and uses a water-soluble binder, and the anode (111) uses a chemical binder, the electrolyte on the cathode (112) side vaporizes well, and the electrolyte on the anode (111) side does not vaporize well, so the surface tension of the anode side where a lot of electrolyte remains is greater, so the separator can be attached to the anode side. If the first heat treatment step (S400) is performed under these conditions, the separator can be attached only to the anode (111) side, so there is an advantage that there is no need to separate the separator from the cathode separately.

[0083] In addition, as a method of physically removing the residue of the separator (113) attached to the positive electrode (111) and the negative electrode (112) before crushing the positive electrode (111) and the negative electrode (112), the positive electrode (111) or the negative electrode (112) may be heated and the separator (113) may be peeled off to remove the separator (113), or the residue of the separator (113) may be physically scraped off.

[0084] By removing the separator (113) in this way, environmentally harmful elements can be eliminated and costs for removing hazardous substances can be reduced because the separator (113) is not burned as in the general recycling method of battery cells (100), and the separator (113) can also be recycled.

[0085] Meanwhile, residual electrolyte exists in the positive electrode (111) and negative electrode (112) separated through the electrode separation step (S500), and a second heat treatment step (S510) can be performed to additionally remove this. The second heat treatment step (S510) vaporizes the electrolyte through heat treatment and captures the vaporized residual electrolyte, similar to the first heat treatment step (S400). That is, the second heat treatment step (S510) can be performed including a second heating step and a second electrolyte capture step.

[0086] In the second heating step included in the second heat treatment step (S510), the cell assembly (110) can be heated by supplying heat to the cell assembly (110) using a heating device.

[0087] For example, a heating device may heat the cell assembly (110) by supplying hot air having a predetermined temperature range. In another example, the heating device may be provided as a device such as a chamber having an internal space, and the cell assembly (110) may be heated by increasing the internal temperature. In addition, various methods for heating the cell assembly (110) may be utilized.

[0088] In addition, in the second heating step, the temperature of the hot air applied to the cell assembly (110) or the temperature inside the chamber is preferably 90 to 250 degrees, which is a condition for completely removing the remaining electrolyte. Since the positive and negative electrodes are already separated, there is no need to worry about them mixing, so it is okay even if the electrolyte completely vaporizes, dries, and crumbles into powder. In addition, since the vaporization temperature of the binder included in the electrolyte is 247 degrees, it is preferable to heat at a temperature higher than that in order to vaporize the binder as well, and it is preferable that the time for which the corresponding temperature is applied and maintained to the cell assembly (110) is formed to be about 10 to 30 minutes. Referring to FIG. 4, when heated by a heating device in the heating step, the electrolyte vaporizes and becomes a gas, and at this time, an electrolyte collector for collecting the gas can be provided to collect the vaporized electrolyte. When the electrolyte collector collects and removes the electrolyte from the cell assembly (110) after vaporizing it by a predetermined ratio, the adhesive strength of the positive electrode (111), negative electrode (112), and separator (113) that were previously adhered to each other is weakened, making them easier to separate. Meanwhile, the amount of the predetermined electrolyte to be heated and vaporized in the second heating step is preferably 20 to 100% of the remaining electrolyte. However, it is preferable to collect and evaporate as much electrolyte as possible, and the most ideal embodiment is to evaporate and remove 100% of all remaining electrolyte.

[0089] In addition, as the electrolyte is vaporized and removed through the second heating step, the separator (113) shrinks, and as the separator (113) shrinks, the anode (111) and the separator (113) or the cathode (112) and the separator (113), which were fixed to each other, are easily separated from each other. Meanwhile, in order to enable the vaporized electrolyte to be captured without diffusing into another space, it is preferable to perform the second heat treatment step (S510) in a sealed space. The sealed space may be a chamber, a sealed container, or the like. In addition, the electrolyte can be recovered by including a process of cooling and condensing the electrolyte captured through the preceding process.

[0090] In this way, by including the second heat treatment step (S510), the electrolyte among the components of the cell assembly (110) can be evaporated and captured in a gaseous state. In addition, since the electrolyte is removed from the cell assembly (110), it becomes easy to separate the remaining components that were adhered to each other, and the separator (113) shrinks, so that the electrode and the separator (113) can be naturally separated. In addition, since the electrolyte is separated by evaporating only the electrolyte while the separator (113) is present, the positive electrode (111) and the negative electrode (112) do not come into contact, so that a short circuit does not occur, and thus a fire can be prevented. In addition, when the electrolyte is evaporated and removed, the electrolyte, which is an ion contained in the electrolyte, cannot move, and therefore, the charge does not move, so a short circuit does not occur, thereby preventing a fire.

[0091] As shown in Fig. 9, when the positive electrode (111), the negative electrode (112), and the separator (113) are separated through the above-described process, instead of performing a process of recycling the black mass obtained by crushing all components while the electrodes and the separator (113) are combined, the separator is separated separately, and the positive electrode (111) is crushed in the first crusher (400) and the negative electrode is crushed in the second crusher (401) so that each component can be separated separately and recycled in the form of black powder. Therefore, the separation process can be reduced compared to when all components are mixed, thereby ensuring economic feasibility. In other words, since black mass is not recovered but black powder is recovered, the time and cost of refining black mass into black powder can be reduced, and since the positive electrode (111) and the negative electrode (112) are separated separately and crushed, high-purity black powder can be recovered, so the recovery rate can be maximized. In addition, since high-purity black powder is recovered, the post-processing process can also be cost-minimized, and since the secondary battery cell separation method of the embodiment of the present invention described above simplifies and reduces the number of processes, there is also an advantage in that the process can be operated with a minimum number of personnel.

[0092] Referring to FIG. 10, in order to prevent fires in some batteries that are not completely discharged in the method for separating cells of a zero-discharge battery type, it is possible to proceed with the method for separating a pouch-type battery cell (100) by including the cooling steps described below. In addition, it is also possible to include a cooling step in the method for separating a zero-discharge battery cell (100) to ensure the stability of the battery cell (100). The cooling step will be described below.

[0093] The first cooling step (S210) is a step for cooling and deactivating the battery cells (100) supplied in cell units, and can be performed before the first heat treatment step (S400), and specifically, can be performed between the cell supply step (S200) and the casing separation step (S300). The battery cells (100) can be cooled to extremely low temperatures by utilizing a cryogenic method in which the battery cells (100) are placed in a predetermined space containing liquid nitrogen, and of course, other cooling methods capable of cooling the battery cells (100) can be utilized. However, when the battery cells (100) are cooled and the temperature drops, moisture in the air may condense on the battery cells (100), causing a short circuit and a risk of fire. Therefore, it is preferable that the first cooling step (S210) be performed in a dry atmosphere without moisture in the air. Therefore, a dry environment can be created by utilizing equipment capable of controlling the internal environment, such as a chamber, or by utilizing a moisture removal device or an inert gas, such as nitrogen. Additionally, the first cooling step (S210) may be omitted as a step to prevent fire in the battery cell (100).

[0094] By including the first cooling step (S210) in this way, the stability of the battery cell (100) can be secured, thereby preventing fire from occurring during subsequent steps.

[0095] The second cooling step (S410) is a process of cooling the cell assembly (110) from which the electrolyte, heated and heated in the first heat treatment process, has been vaporized, to room temperature. This process can be performed after the first heat treatment. To rapidly induce cooling, a cooling device that emits air at a predetermined temperature can be included to introduce cool air. Alternatively, the temperature can be rapidly lowered by forming a nitrogen atmosphere in the air.

[0096] Meanwhile, in the third cooling step (S420) to be described later, the cell assembly (110) is cooled again. If the second cooling step (S410) is performed, less material for lowering the temperature, such as the refrigerant used in the third cooling step (S420), can be used, which is economical. In addition, by gradually lowering the temperature from room temperature, the cell assembly (110) can be less affected by the impact of rapid temperature changes.

[0097] The third cooling step (S420) is a step of cooling and deactivating the cell assembly (110) from which the electrolyte has been removed through the first heat treatment step (S400), and can be performed before the electrode separation step (S500), and specifically, can be performed after the first heat treatment or the second cooling step (S410). The third cooling step (S420) is a step of the same method as the first cooling step (S210) except that the target is different. Therefore, the third cooling step (S420) can cool the cell assembly (110) from which the electrolyte has been removed to an extremely low temperature by utilizing a cryogenic method, and of course, other cooling methods can be utilized. However, since there is a risk that when the cell assembly (110) is cooled and the temperature drops, moisture in the air may condense on the cell assembly (110), causing a short circuit and resulting in a fire, the third cooling step (S420) is preferably performed in a dry atmosphere without moisture in the air, and a dry environment can be created by using equipment capable of controlling the internal environment, such as a chamber, or by using a moisture removal device or an inert gas, such as nitrogen. In addition, the third cooling step (S420) may be omitted because it is a step for preventing a fire in the battery cell (100).

[0098] By including the third cooling step (S420) in this way, the stability of the cell assembly (110) can be secured, thereby preventing fire from occurring during subsequent steps.

[0099] Meanwhile, as described above, the second cooling step (S410) can be used to reduce the impact caused by rapid temperature changes, and by performing the third cooling step (S420) after the second cooling, it is possible to secure economic efficiency by using less refrigerant, etc. to be used in the third cooling step (S420). However, even though the second cooling step (S410) includes such effects, the second cooling step (S410) can be omitted and only the third cooling step (S420) can be performed.

[0100] Meanwhile, when the third cooling step (S420) is performed, as in the second cooling step (S410), the cell assembly (110) is cooled and the temperature drops, so there is a risk that moisture in the air may condense on the cell assembly (110), causing a short circuit and resulting in a fire. Therefore, it is preferable that the electrode separation step (S500) be performed in a dry atmosphere without moisture in the air. A dry environment can be created by using equipment capable of controlling the internal environment, such as a chamber, or by using a moisture removal device or an inert gas, such as nitrogen.

[0101]

[0102] The method for separating cylindrical secondary battery cells can be divided into a method using a discharged battery and a method using a non-discharged battery. However, both methods can separate the battery cell (100) through the same process, but in the case of using a non-discharged battery, since no discharging is performed, the manpower and space required for discharging can be maximized, and since a discharger is not used, the investment cost can be minimized, making it economical. Hereinafter, a common process of a method for separating cylindrical secondary battery cells will be described. Referring to FIG. 1, the method for separating secondary battery cells includes an opening step (S200) of opening a portion of a frame (124), a first heat treatment step (S300) of heating the cell assembly (110) to vaporize the electrolyte, and an electrode separation step (S500) of separating the positive electrode (111), the negative electrode (112), and the separator, and then each component of the battery cell (100) can be separated and then crushed. However, a cell supply step may be further performed before the first heat treatment, and a frame separation step (S400) may be further included before the electrode separation process, so that each component of the battery cell (100) may be separated and then crushed. That is, in the cylindrical secondary battery cell separation method, unlike the pouch type, each step is defined and described as above in FIGS. 1 and 20.

[0103] The cell supply step (S100) is a step of supplying cells to a battery cell (100) separation line according to the present invention. The cell supply step (S100) may include a process of disassembling a battery in a module unit, so that the battery cells (100) can be supplied in preparation for subsequent processes. Meanwhile, one embodiment of the present invention provides a process of simultaneously disassembling a plurality of secondary battery cells included in a secondary battery cell group including two or more secondary battery cells that are electrically connected to each other through a connecting electrode, which will be described later, and arranged in a grid shape.

[0104] Referring to FIG. 14, the frame (124) is formed in a cylindrical shape that surrounds the cell assembly (110), and the center of the cylinder is empty, or the components of the cell assembly (110) are wound around a cylindrical core (130).

[0105] Meanwhile, referring to FIGS. 11 and 12, the battery cell (100) may be formed of two or more aligned secondary battery cell groups that are electrically connected to each other and arranged in a grid shape, and the cell groups may be formed as secondary batteries in the form of modules or packs. At this time, in order to electrically connect the battery cells (100), a connecting electrode (410) that connects an external positive electrode and an external negative electrode formed on the outside of the battery cell (100) may be provided, respectively. That is, there is a connecting electrode that connects the positive electrodes of the secondary battery cells, and there is a connecting electrode that connects the negative electrodes, respectively. In addition, the outside is wrapped with a cover (430), and the inside is filled with a resin (420) to fix the battery cell (100) and the connecting electrode (410), but the resin (420) is omitted in some drawings.

[0106] The secondary battery cell group formed in this way can perform a separation process similar to the process of separating one battery cell (100), and at this time, two or more battery cells (100) arranged and aligned can perform the separation process simultaneously.

[0107] Referring to Fig. 13, before the opening step (S200), the electrical connection means between the battery cells (100) can be cut to electrically insulate and short-circuit each battery cell (100). This is done by cutting the connecting electrode (410) described above. Referring to Fig. 13, the connecting electrode (410) provided between the battery cells (100) can be cut using a connecting electrode cutting device (413) capable of cutting the connecting electrode (410). Referring to the connecting electrode cutting portion (414) of Fig. 4, it can be confirmed that one row or column of the connecting electrode (410) is completely cut, and when all of the cutting portions represented by dotted lines are cut, each battery cell (100) is electrically insulated and short-circuited, and operates as only one battery cell.

[0108] By performing the process of short-circuiting between battery cells (100) in this way, each cell is electrically isolated, and the probability of occurrence of risk factors such as fire or explosion that may occur when all battery cells (100) are connected can be reduced.

[0109] The opening step (S200) is a step of opening the battery cell (100) by forming a hollow (121) in the center portion (122) of the upper surface of the cylindrical battery. Referring to FIG. 15, the opening step (S200) can be performed through an opening device (123), and the hollow (121) is formed on the upper or lower surface, but it is also possible to form the hollow (121) on both the upper and lower surfaces. The hollow (121) can also be formed on the side surface, but considering the structure of the cylindrical battery of FIG. 14, it is preferable to form the hollow (121) on the upper and lower surfaces because the hollow (121) formed on the side surface may come into contact with the electrode and cause a short circuit.

[0110] In addition, a hollow (121) is formed in the center portion (122), which is the center of the upper or lower surface, because the cylindrical battery is formed with an empty center or including a core (130). This is to prevent the opening device (123) from being inserted too far into the center portion (122) to process the hollow (121) and from being inserted toward the empty space or the core (130) rather than the electrode side, thereby preventing a short circuit. Meanwhile, another reason for processing the hollow (121) in the upper and lower surfaces is that a certain space is provided in the upper or lower surface to include a configuration such as a gasket due to the structure of the cylindrical battery. Referring to FIGS. 14 and 15, such a space can be confirmed, and can act as a kind of buffer to prevent the opening device (123) from coming into contact with the electrodes, etc., even if it is inserted too far. However, the space is due to technical limitations, and attempts to continuously eliminate the space are being made, and even if there is no certain space on the upper or lower surface of the cylindrical battery described above, a hollow (121) can be formed by inserting the opening device (123) up to the part where the tab of the battery is located. In addition, when inserted toward the core (130) of the center portion (122) described above, a hollow (121) can be formed without causing a short circuit even if there is no space. That is, the opening step (S200) can form a hollow on the upper or lower surface of the cylindrical battery cell regardless of the presence or absence of space.

[0111] When the hollow (121) is processed through the opening step, the electrolyte is vaporized from the inside of the cylindrical battery to the outside in the first heat treatment step (S300) to be described later and can escape through the hollow (121).

[0112] The first heat treatment step (S300) is a step of heat-treating a cell assembly (110) including a positive electrode (111), a negative electrode (112), an electrolyte, and a separator (113) inside a battery cell (100). The electrolyte is vaporized through the heat treatment and the vaporized electrolyte is captured. That is, the first heat treatment step (S300) may be performed including a first heating step and a first electrolyte capture step.

[0113] Meanwhile, the first electrolyte capture step can be performed by capturing the vaporized electrolyte, transporting it to a relatively low-temperature space, allowing it to condense and then collect it as a liquid. Because the electrolyte emits a pungent odor when vaporized and is environmentally harmful, it is desirable to capture it by including the electrolyte capture step. Capturing the electrolyte through the aforementioned electrolyte capture step allows for recycling or easy disposal.

[0114] In the first heating step included in the first heat treatment step (S300), the temperature of the cell assembly (110) can be increased by supplying heat to the cell assembly (110) using a heating device.

[0115] For example, a heating device may supply hot air having a predetermined temperature range to increase the temperature of the cell assembly (110). In another example, the heating device may be provided as a device such as a chamber having an internal space, thereby increasing the temperature of the cell assembly (110). In addition, various methods for increasing the temperature of the cell assembly (110) may be utilized.

[0116] In addition, in the first heating step, the temperature of the hot air applied to the cell assembly (110) or the temperature inside the chamber is preferably 90 to 250 degrees, and the time for which the temperature is applied to the cell assembly (110) and maintained is preferably formed to be about 20 minutes to 1 hour. Referring to FIG. 16, when the temperature is raised by a heating device that raises the temperature in the heating step, the electrolyte is vaporized and becomes a gas, and at this time, an electrolyte collecting device (200) that collects the gas can be provided to collect the vaporized electrolyte. When the electrolyte collecting device (200) vaporizes the electrolyte to a predetermined ratio or more and then collects it and removes it from the cell assembly (110), it becomes easy to separate the positive electrode (111), the negative electrode (112), and the separator (113) from which the electrolyte has been removed. Meanwhile, if the electrolyte is excessively vaporized and removed in the first heat treatment step (S300), the positive electrode (111) or negative electrode (112) may become excessively dry and fall off as powder, and may mix with each other, resulting in a reduced recovery rate. Therefore, it is preferable that the amount of the predetermined electrolyte to be collected after vaporization in the first heat treatment step (S300) be 20 to 50% of the total electrolyte.

[0117] In addition, the electrolyte is vaporized during the first heating step. To ensure that the vaporized electrolyte is captured without diffusing into other spaces, it is preferable to perform the first heat treatment step (S300) in a sealed space. The sealed space may be a chamber, a sealed container, or the like. In addition, the electrolyte can be recovered by including a process of cooling and condensing the electrolyte captured through the preceding process.

[0118] In this way, by including the first heat treatment step (S300), the electrolyte among the components of the cell assembly (110) can be evaporated and captured in a gaseous state. In addition, since the electrolyte is removed from the cell assembly (110), it becomes easy to separate the remaining components, and since the electrolyte is separated by evaporating only the electrolyte while the separator (113) is present, the positive electrode (111) and negative electrode (112) do not come into contact, so that a short circuit does not occur, and thus a fire can be prevented. In addition, since the electrolyte is evaporated and removed, the electrolyte, which is an ion included in the electrolyte, cannot move, so that lithium movement is prevented, thereby preventing a fire.

[0119] The battery cell (100) is configured to include a cell assembly (110) including a positive electrode (111), a negative electrode (112), an electrolyte, and a separator (113) inside, and a frame (124) surrounding the cell assembly (110), and a frame separation step (S400) for separating the frame (124) is performed between the first heat treatment step (S300) and the electrode separation step (S500).

[0120] Referring to FIGS. 17 and 18, the frame separation step (S400) may include an upper surface cutting step for cutting the upper surface of the battery cell (100), a lower surface cutting step for cutting the lower surface of the battery cell (100), and a cell assembly (110) collection step for collecting the cell assembly (110) contained within the frame (124) with both sides cut.

[0121] Referring to the first picture of FIG. 17, the empty space that does not include the electrodes on the upper and lower surfaces of the cylindrical battery cell is cut, and the upper and lower surfaces are sequentially cut so that both the upper and lower surfaces are removed as shown in the last picture. However, the order of cutting the upper and lower surfaces may be switched. Thereafter, the cell assembly (110) contained in the frame (124) with both sides cut can be collected. However, the empty space that does not include the electrodes described above is due to technical limitations, and since attempts to continuously eliminate the space are being made, it is possible to cut up to the part where the tab of the battery is present even if there is no empty space on the upper or lower surface of the cylindrical battery described above. That is, in the frame separation step (S400), the upper and lower surfaces of the cylindrical battery cell can be cut to remove the upper and lower surfaces regardless of the presence or absence of space.

[0122] Fig. 18 is a drawing showing a cell aggregate collection step. Referring to Fig. 18, the cell aggregate collection step of collecting a cell aggregate (110) contained in a frame (124) with both sides cut off can collect the cell aggregate (110) by pushing the cell aggregate (110) out of the frame (124) with a press bar (140) having a smaller diameter than the frame (124). Since the wound cell aggregate (110) is tightly fitted to the frame (124), it is not easily separated by simply pushing or pulling it out of the frame (124).

[0123] Accordingly, a press bar (140) having a smaller diameter than the frame (124) can be provided to push the cell assembly (110) out of the frame (124). At this time, the entire cell assembly (110) can be pushed out, or rather than pushing out the entire cell assembly (110), the center of the cell assembly (110) can be pushed out so that a portion of the positive electrode (111), negative electrode (112), and separator (113) of the cell assembly (110) wound around the center can protrude to the opposite side. In this way, when the center is pushed out and begins to protrude, the entire assembly can eventually come out, and the cell assembly (110) can be separated from the frame (124) more easily than when pushing out the entire assembly.

[0124] Meanwhile, in the case of performing separation on two or more aligned secondary battery cell groups arranged in a grid shape, the step may be performed by cutting the upper and lower surfaces of all battery cells (100) simultaneously, as shown in FIG. 19.

[0125] By separating the frame (124) including the frame separation step (S400) in this way, the cell assembly (110) contained therein can be separated, and the frame (124) can be separated and recycled separately.

[0126] The electrode separation step (S500) is a step of separating the positive electrode (111), the negative electrode (112), and the separator (113) from the cell assembly (110) from which the electrolyte has been removed. The electrode separation step (S500) is a step for separating and crushing the negative electrode (112) and the positive electrode (111) separately so that they can be recycled, since the materials of the negative electrode (112) and the positive electrode (111) are different.

[0127] Referring to Fig. 14, a positive electrode (111), a negative electrode (112), and a separator (113) are rolled up and overlapped inside a cylindrical battery cell (100). In the electrode separation step (S500), the positive electrode (111), the negative electrode (112), and the separator (113) formed in this manner can be spread out and separated. At this time, a support tape can be attached to prevent the rolled components from unraveling and becoming disordered. By removing this, the electrode separation step (S500) can be performed.

[0128] Meanwhile, electrolyte residues exist in the positive electrode (111) and negative electrode (112) separated through the electrode separation step (S500), and a second heat treatment step (S510) can be performed to additionally remove them. The second heat treatment step (S510), like the first heat treatment step (S300), vaporizes the electrolyte through heat treatment and captures the vaporized electrolyte. That is, the second heat treatment step (S510) can be performed including a second heating step and a second electrolyte capture step.

[0129] In the second heating step included in the second heat treatment step (S510), the temperature of the cell assembly (110) can be increased by supplying heat to the cell assembly (110) using a heating device.

[0130] For example, a heating device may supply hot air having a predetermined temperature range to increase the temperature of the cell assembly (110). In another example, the heating device may be provided as a device such as a chamber having an internal space, thereby increasing the temperature of the cell assembly (110). In addition, various methods for increasing the temperature of the cell assembly (110) may be utilized.

[0131] In addition, the temperature of the hot air applied to the cell assembly (110) in the second heating step or the temperature inside the chamber is preferably 150 to 250 degrees, which is a condition for completely removing the remaining electrolyte. Since the positive and negative electrodes are already separated, there is no need to worry about them mixing, so it is okay even if the electrolyte completely evaporates, dries, and crumbles into powder. In addition, since the vaporization temperature of the binder included in the electrolyte is 247 degrees, it is preferable to heat at a temperature higher than that in order to vaporize the binder as well. It is preferable that the time for which the temperature is applied to the cell assembly (110) and maintained is formed to be about 10 to 30 minutes. Referring to FIG. 13, when the temperature is raised by a heating device that raises the temperature in the heating step, the electrolyte is vaporized and becomes a gas, and at this time, an electrolyte collecting device (200) that collects the gas can be provided to collect the vaporized electrolyte. Meanwhile, the amount of electrolyte heated and vaporized in the second heating step is preferably 20-100% of the remaining electrolyte. However, it is desirable to evaporate and capture as much electrolyte as possible, and the optimal embodiment is ideally to evaporate and remove 100% of all remaining electrolyte.

[0132] Additionally, to ensure that the vaporized electrolyte is captured without spreading to other spaces, it is preferable to conduct the second heat treatment step (S510) in a sealed space. The sealed space may be a chamber, a sealed container, or the like. Furthermore, the electrolyte can be recovered by including a process for cooling and condensing the electrolyte captured through the preceding process.

[0133] In this way, by including the second heat treatment step (S510), the electrolyte among the components of the cell assembly (110) can be evaporated into a gaseous state and captured. In addition, since the electrolyte is separated by evaporating only the electrolyte while the separator (113) is present, the positive electrode (111) and negative electrode (112) do not come into contact, so that a short circuit does not occur and a fire can be prevented. In addition, when the electrolyte is evaporated and removed, the electrolyte, which is an ion contained in the electrolyte, cannot move, and therefore, lithium does not move, so a short circuit does not occur and a fire is prevented.

[0134] By separating the positive electrode (111), the negative electrode (112), and the separator (113) through the above-described process, instead of performing a process of recycling the black mass obtained by crushing all components while the electrode and separator (113) are combined, each component can be separated separately and recycled in the form of black powder, thereby reducing the separation process compared to when all components are mixed, thereby ensuring economic feasibility. In other words, since black mass is not recovered but rather recovered as black powder, the time and cost of refining black mass into black powder can be reduced, and since the positive electrode (111) and the negative electrode (112) are separated and crushed separately, high-purity black powder can be recovered, thereby maximizing the recovery rate. In addition, since high-purity black powder is recovered, the cost of the post-processing process can also be minimized, and since the secondary battery cell separation method of the embodiment of the present invention described above simplifies and reduces the number of processes, there is also an advantage in that the process can be operated with a minimum number of personnel.

[0135] Figure 20 is a flowchart of a secondary battery cell separation method including cooling steps. Referring to this, in order to prevent fires in some batteries that are not completely discharged in a cell separation method of a non-discharge battery type, it is possible to proceed with a battery cell (100) separation method including the cooling steps described below. Furthermore, in order to ensure the stability of the battery cell (100) in a non-discharge battery cell separation method, it is also possible to include a cooling step. The cooling step will be described below.

[0136] The first cooling step (S110) is a step for cooling and deactivating the battery cells (100) supplied in cell units, and can be performed between the cell supply step (S100) and the opening step (S200). The battery cells (100) can be cooled to extremely low temperatures by utilizing a cryogenic method in which the battery cells (100) are placed in a predetermined space containing liquid nitrogen, and of course, other cooling methods capable of cooling the battery cells (100) can be utilized. However, when the battery cells (100) are cooled and the temperature drops, moisture in the air may condense on the battery cells (100), causing a short circuit and a risk of fire. Therefore, it is preferable that the first cooling step (S110) be performed in a dry atmosphere without moisture in the air. Therefore, a dry environment can be created by utilizing equipment capable of controlling the internal environment, such as a chamber, or by utilizing a moisture removal device or an inert gas, such as nitrogen. Additionally, the first cooling step (S110) may be omitted as a step to prevent fire in the battery cell (100).

[0137] By including the first cooling step (S110) in this way, the stability of the battery cell (100) can be secured, thereby preventing fire from occurring during subsequent steps.

[0138] The second cooling step (S310) is a process of cooling the cell assembly (110) from which the electrolyte, heated and heated in the first heat treatment process, has been vaporized, to room temperature. This process can be performed after the first heat treatment. To rapidly induce cooling, a cooling device that emits air at a predetermined temperature can be included to introduce cool air. Alternatively, the temperature can be rapidly lowered by forming a nitrogen atmosphere in the air.

[0139] Meanwhile, in the third cooling step (S320) to be described later, the cell assembly (110) is cooled again. If the second cooling step (S310) is performed, less material for lowering the temperature, such as the refrigerant used in the third cooling step (S320), can be used, which is economical. In addition, by gradually lowering the temperature from room temperature, the cell assembly (110) can be less affected by the shock caused by rapid temperature changes.

[0140] The third cooling step (S320) is a step of cooling and deactivating the cell assembly (110) from which the electrolyte has been removed through the first heat treatment step (S300), and can be performed after the first heat treatment or the second cooling step (S310) and before the frame separation step (S400). The third cooling step (S320) is a step of the same method as the first cooling step (S110) except that the target is different. Therefore, the third cooling step (S320) can cool the cell assembly (110) from which the electrolyte has been removed to an extremely low temperature by utilizing a cryogenic method, and of course, other cooling methods can be utilized. However, since there is a risk that when the cell assembly (110) is cooled and the temperature drops, moisture in the air may condense on the cell assembly (110), causing a short circuit and resulting in a fire, the third cooling step (S320) is preferably performed in a dry atmosphere without moisture in the air, and a dry environment can be created by using equipment capable of controlling the internal environment, such as a chamber, or by using a moisture removal device or an inert gas, such as nitrogen. In addition, since the third cooling step (S320) is a step for preventing a fire in the battery cell (100), it can be omitted.

[0141] By including the third cooling step (S320) in this way, the stability of the cell assembly (110) can be secured, thereby preventing fire from occurring during subsequent steps.

[0142] Meanwhile, as described above, the second cooling step (S310) can be used to reduce the impact caused by rapid temperature changes, and by performing the third cooling step (S320) after the second cooling, it is possible to secure economic efficiency by using less refrigerant, etc. to be used in the third cooling step (S320). However, even though the second cooling step (S310) includes these effects, the second cooling step (S310) can be omitted and only the third cooling step can be performed.

[0143] Meanwhile, when the third cooling step (S320) is performed, as in the second cooling step (S310), the cell assembly (110) is cooled and the temperature drops, so there is a risk that moisture in the air may condense on the cell assembly (110), causing a short circuit and resulting in a fire. Therefore, it is preferable that the electrode separation step (S500) be performed in a dry atmosphere without moisture in the air. A dry environment can be created by using equipment capable of controlling the internal environment, such as a chamber, or by using a moisture removal device or an inert gas, such as nitrogen.

[0144] The above-described preferred embodiments of the present invention are disclosed for the purpose of illustration, and those skilled in the art will be able to make various modifications, changes, and additions within the spirit and scope of the present invention, and such modifications, changes, and additions should be considered to fall within the scope of the above-described claims. In addition, those skilled in the art to which the invention pertains can make various substitutions, modifications, and changes without departing from the technical spirit of the present invention, and therefore the present invention is not limited to the above-described embodiments and the attached drawings.

[0145] In the exemplary system described above, the methods are described based on a flowchart as a series of steps or blocks. However, the present invention is not limited to the order of the steps, and some steps may occur in a different order or simultaneously with other steps described above. Furthermore, those skilled in the art will understand that the steps depicted in the flowchart are not exclusive, and other steps may be included, or one or more steps in the flowchart may be deleted without affecting the scope of the present invention.

[0146]

[0147] According to the present invention, the configuration of the battery cell can be separated and recycled individually.

[0148] Additionally, by evaporating the electrolyte while the separator is present, fire can be prevented during the separation process.

[0149] Additionally, by separating the positive and negative electrodes and recycling them, the recovery rate can be increased and the recovery cost can be reduced.

[0150] Additionally, it removes environmental hazards without burning the membrane, reduces the cost of removing hazardous substances, and allows the membrane itself to be recycled.

Claims

1. A method for separating a battery cell including a cell assembly composed of a positive electrode, a negative electrode, an electrolyte, and a separator, A first heat treatment step of heating the cell assembly to vaporize the electrolyte; A secondary battery cell separation method comprising an electrode separation step of separating a positive electrode or a negative electrode from a separator.

2. In paragraph 1, The above battery cell further includes a casing surrounding the cell assembly, Before the first heat treatment step A secondary battery cell separation method, characterized in that it further includes a casing separation step for separating the casing and the cell assembly.

3. In paragraph 1, Even after the first heat treatment step, A secondary battery cell separation method characterized in that the separator separates the positive electrode and the negative electrode.

4. In paragraph 1, In the first heat treatment step, A secondary battery cell separation method characterized by vaporizing only a portion of the electrolyte.

5. In paragraph 4, A secondary battery cell separation method characterized in that the electrolyte vaporizes 20 to 50% of the total electrolyte.

6. In paragraph 1, A secondary battery cell separation method characterized in that it further includes a separator separation step for removing the separator remaining on the positive or negative electrode after the electrode separation step.

7. In paragraph 6, The above membrane separation step A secondary battery cell separation method characterized by heating the positive or negative electrode and peeling or physically scraping the separator from the positive or negative electrode.

8. In paragraph 1, A secondary battery cell separation method characterized in that it further includes a second heat treatment step of heating the cell assembly to vaporize the remaining electrolyte to remove the remaining electrolyte remaining in the cell assembly before or after the electrode separation step, and capturing the vaporized remaining electrolyte.

9. In paragraph 1, Before the first heat treatment step A secondary battery cell separation method, characterized in that it further comprises a first cooling step for cooling the battery cell.

10. In paragraph 1, It is performed between the first heat treatment step and the electrode separation step, A secondary battery cell separation method, characterized in that it further comprises a second cooling step for cooling the battery cell.

11. In paragraph 1, Before the electrode separation step, A secondary battery cell separation method characterized in that it further includes a third cooling step of cooling the battery cell.

12. In any one of paragraphs 9 to 11, The first cooling step or the second cooling step, A secondary battery cell separation method characterized by being cryogenic.

13. In paragraph 1, Before the first heat treatment step, A secondary battery cell separation method characterized by further including a module disassembly step of disassembling a module-based battery into cell-based batteries.

14. In paragraph 1, The above electrode separation step is, A secondary battery cell separation method characterized by sequentially separating the stacked positive electrode, separator, and negative electrode from the top.

15. In paragraph 1, The above electrode separation step is, It is characterized by further including a membrane separation step for removing the membrane remaining on the positive or negative electrode, The above membrane separation step is, A secondary battery cell separation method characterized in that the separated positive and negative electrodes are each crushed and the separator is separated through the difference in specific gravity.

16. In paragraph 1, The above first heat treatment step is, A secondary battery cell separation method characterized in that the separator is separated in a state where it is attached only to the positive electrode when the separation is performed within 20 minutes at a temperature of 120 degrees.

17. In paragraph 1, The above electrode separation step is, A secondary battery cell separation method characterized in that the positive electrode, negative electrode, and separator are crushed together without separate separation.

18. In paragraph 1, After the above electrode separation step, A secondary battery cell separation method characterized in that it further includes a stabilization step of contacting water with the positive or negative electrode.

19. A method for separating a battery cell, comprising a cell assembly composed of a positive electrode, a negative electrode, an electrolyte, and a separator, and a frame sealing the cell assembly, An opening step for opening a portion of the above frame; A first heat treatment step of heating the cell assembly to vaporize the electrolyte; and A secondary battery cell separation method comprising an electrode separation step of separating the positive or negative electrode from the separator.

20. In paragraph 19, The above frame is formed in a cylindrical shape that surrounds the cell assembly, A secondary battery cell separation method characterized in that the above cell assembly configurations are wound around a cylindrical core.

21. In paragraph 19, A secondary battery cell separation method, characterized in that the above battery cells are two or more aligned battery cells that are electrically connected to each other through connecting electrodes and arranged in a grid shape.

22. In paragraph 21, Before the above opening step, A method for separating secondary battery cells, characterized in that each secondary battery cell is short-circuited by cutting the electrical connection means between the battery cells.

23. In paragraph 20, A secondary battery cell separation method, characterized in that the above opening step forms a hollow in the center portion of the upper surface of the battery cell to open the battery cell.

24. In paragraph 19 or paragraph 21, Between the first heat treatment step and the electrode separation step, A secondary battery cell separation method, characterized in that it further includes a frame separation step for separating the cell assembly and the frame.

25. In paragraph 24, The above frame separation step is, A top cutting step for cutting the top surface of the above battery cell, A bottom cutting step for cutting the bottom surface of the above battery cell, A secondary battery cell separation method, characterized in that it includes a cell assembly collection step of collecting a cell assembly contained in the frame with both sides cut.

26. In paragraph 25, The above frame separation step is, A secondary battery cell separation method characterized by simultaneously separating two or more aligned battery cells arranged in a grid shape.

27. In paragraph 19, Even after the first heat treatment step, A secondary battery cell separation method characterized in that the separator separates the positive electrode and the negative electrode.

28. In paragraph 19, In the first heat treatment step, A secondary battery cell separation method characterized by vaporizing only a portion of the electrolyte.

29. In paragraph 28, A secondary battery cell separation method characterized in that the electrolyte vaporizes 20 to 50% of the total electrolyte.

30. In paragraph 19, A secondary battery cell separation method characterized in that it further includes a separator separation step for removing the separator remaining on the positive or negative electrode after the electrode separation step.

31. In paragraph 30, The above membrane separation step A secondary battery cell separation method characterized by heating the positive or negative electrode and peeling or physically scraping the separator from the positive or negative electrode.

32. In paragraph 19, A secondary battery cell separation method characterized in that it further includes a second heat treatment step of heating the cell assembly to vaporize the remaining electrolyte to remove the remaining electrolyte remaining in the cell assembly before or after the electrode separation step, and capturing the vaporized remaining electrolyte.

33. In paragraph 19, Before the first heat treatment step A secondary battery cell separation method, characterized in that it further comprises a first cooling step for cooling the battery cell.

34. In paragraph 19, It is performed between the first heat treatment step and the electrode separation step, A secondary battery cell separation method, characterized in that it further comprises a second cooling step for cooling the battery cell.

35. In paragraph 19, Before the electrode separation step, A secondary battery cell separation method characterized in that it further includes a third cooling step of cooling the battery cell.

36. In any one of paragraphs 34 to 35, The first cooling step or the second cooling step, A secondary battery cell separation method characterized by being cryogenic.

37. In paragraph 25, The above cell cluster collection step is, A secondary battery cell separation method characterized in that the cell assembly is pushed out of the frame by a press bar having a diameter smaller than the frame.

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