Apparatus for activating battery cell and method for activating battery cell using the same

Abstract

According to an exemplary embodiment of the present invention, a battery cell activation device is provided. The apparatus includes: a driving portion including a driving plate and a driving rod configured to move the driving plate in a first direction; and a supporting portion including a supporting plate and an elastic element connected to the supporting plate, in which the supporting plate is spaced apart from the driving plate in the first direction and includes a protruding portion protruding in the first direction.

Description

Technical Field

[0001] The present invention relates to a battery cell formation device and a battery cell formation method using the same. This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0176240, filed on December 7, 2023, and the entire contents of the Korean Patent Application are incorporated herein by reference. Background Art

[0002] Unlike primary batteries, secondary batteries can be charged and discharged multiple times. Secondary batteries have been widely used as energy sources for various types of wireless devices (such as handheld devices, laptop computers and cordless vacuum cleaners). Recently, the main use of secondary batteries has shifted from mobile devices to mobility, as the manufacturing cost per unit capacity of secondary batteries has dropped sharply due to improved energy density and economies of scale, and the cruising range of battery electric vehicles (BEVs) has increased to the same level as fuel vehicles.

[0003] The manufacturing of secondary batteries involves the electrode process, which includes mixing, coating, rolling, cutting, and slotting; the assembly process, which embeds the electrode assembly into the housing; and the formation process, which electrically activates and stabilizes the battery cells. After the formation process, the battery cells can be stacked to form a cell stack. The cell stack can be installed in the housing with a module frame or directly in the housing without a module frame. Summary of the Invention

[0004] [Technical Issues]

[0005] The present invention aims to provide a battery cell formation apparatus having improved reliability and a battery cell formation method using the same.

[0006] [Technical solution]

[0007] An example embodiment of the present invention provides a battery cell formation device. The battery cell formation device includes: a driving portion including a driving plate and a driving rod configured to move the driving plate in a first direction; a supporting portion including a supporting plate spaced apart from the driving plate in the first direction and an elastic element connected to the supporting plate; and a plurality of pressing plates disposed between the driving portion and the supporting plate and configured to press a plurality of battery cells, the supporting plates including protrusions protruding in the first direction.

[0008] A height of each of the protrusions in the first direction may be in the range of 0.1 mm to 1.0 mm.

[0009] A height of each of the protrusions in the first direction may be 0.6 mm or less.

[0010] Each of the protrusions may comprise the same material as the support plate.

[0011] Each of the protrusions may include a material different from that of the support plate.

[0012] The protrusion may be spaced apart from the center of the support plate.

[0013] The protrusions may be spaced apart from each other in a second direction parallel to the support plate, and spaced apart from a center of the support plate in the second direction.

[0014] A distance between an end portion of the support plate in the second direction and the protrusion may be different from a distance between the protrusion and a center of the support plate in the second direction.

[0015] A distance between an end portion of the support plate in the second direction and the protrusion may be smaller than a distance between the protrusion and a center of the support plate in the second direction.

[0016] Each of the pressed plates may have a flat plate shape.

[0017] Each of the pressed plates may not include a protrusion.

[0018] A surface of each of the pressed plates may have a shape different from a shape of a surface of the support plate.

[0019] Example embodiments provide a secondary battery formation method. The method includes: loading a plurality of pressure-sensitive papers and a plurality of battery cells onto a battery cell formation device; performing a formation process on the plurality of battery cells; and evaluating the formation process of the plurality of battery cells based on the plurality of pressure-sensitive papers. The battery cell formation device includes a driving portion and a supporting portion, the driving portion including a driving plate and a driving rod configured to move the driving plate in a first direction; the supporting portion including a supporting plate and an elastic element connected to the supporting plate, the supporting plate being spaced apart from the driving plate in the first direction and including a protrusion protruding in the first direction.

[0020] Evaluation of the forming process may be performed based on a standard deviation of pressures sensed using the plurality of sheets of pressure-sensitive paper.

[0021] [Beneficial Effects]

[0022] The battery cell formation apparatus according to an exemplary embodiment of the present invention includes a support plate having protrusions, thereby allowing the battery cells to be uniformly compressed during the formation process and improving the reliability of manufacturing a secondary battery.

[0023] The effects that can be achieved from the exemplary embodiments of the present invention are not limited to the above-mentioned effects, and those skilled in the art to which the exemplary embodiments of the present invention pertain will clearly derive and understand other effects not described herein from the following description. In other words, the unexpected effects achieved when implementing the exemplary embodiments of the present invention can be derived from the exemplary embodiments of the present invention by those skilled in the art. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a plan view of a battery cell formation apparatus according to example embodiments.

[0025] Figure 2 is a partial plan view of a battery cell formation apparatus according to example embodiments.

[0026] Figure 3 is a flowchart of a secondary battery manufacturing method according to example embodiments.

[0027] Figure 4 A pressure-sensitive paper according to an example embodiment is shown.

[0028] Figure 5 A pressure-sensitive paper according to an example embodiment is shown. DETAILED DESCRIPTION

[0029] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Before describing the embodiments of the present invention, the terms or expressions used in this specification and claims should not be interpreted as limited to those generally understood or defined in commonly used dictionaries, and should be understood based on the meaning and concept corresponding to the present invention, based on the inventors of the present application who can appropriately define the terms or expressions to best explain the principles of the present invention.

[0030] Therefore, the embodiments described herein and the configurations shown in the accompanying drawings are merely examples of the present invention and do not reflect all technical concepts of the present invention. Therefore, it should be understood that various equivalents and modifications will be made to replace these configurations on the filing date of this application.

[0031] When it is determined that well-known configurations or functions related to describing the present invention would obscure the subject matter of the present invention with unnecessary detail, they are not described in detail.

[0032] Since the embodiments of the present invention are provided to explain the present invention more comprehensively to those skilled in the art, the shapes, sizes, etc. of the components shown in the drawings may be exaggerated, omitted, or schematically illustrated for the sake of clarity. Therefore, it should not be understood that the sizes or ratios of the components fully reflect their actual sizes or ratios.

[0033] (First embodiment)

[0034] Figure 1is a perspective view of a battery cell formation apparatus 100 according to example embodiments.

[0035] Reference Figure 1 The battery cell formation device 100 may include a driving portion 110 , a supporting portion 120 and a plurality of pressing plates 130 .

[0036] According to example embodiments, the battery cell formation apparatus 100 may be configured to perform a formation process of the battery cell BC. Here, the formation process of the battery cell BC may include repeatedly performing aging, charging, and discharging of the battery cell BC.

[0037] When the electrolyte decomposes due to repetition of charge and discharge, a solid electrolyte interface (SEI) film may be formed on the surface of the negative electrode. The SEI film is a thin film produced on the surface of the negative electrode material when the battery cell BC is charged for the first time after the battery cell BC is manufactured. When the battery cell BC is charged, the lithium ions in the battery cell BC may move to the negative electrode, and due to the chemical reaction that occurs when the material in the electrolyte is electrolyzed for the first time during the movement of the lithium ions, the SEI film may be formed on the surface of the negative electrode material. The SEI film may be a type of separator. When lithium ions move from the positive electrode to the negative electrode to charge the battery, the SEI film may prevent additional decomposition reactions of the electrolyte.

[0038] During the aging process, the battery cells BC can be stored at room temperature for a certain period of time (as a non-limiting example, 30 minutes to 3 hours) to stabilize the battery cells BC during charging or discharging. The key to the aging process is to evenly disperse the electrolyte in the pouch cells so that the electrolyte can evenly penetrate both the positive and negative electrodes. Through the aging process, the mobility of lithium ions can be improved, and the uniformity of the SEI film (e.g., thickness uniformity) can be improved.

[0039] The formation process of the battery cell BC may include performing degassing to remove gas generated in the battery during aging and charging. During the charging / discharging and aging processes, gas may be generated in the battery cell BC. During the degassing process, the gas in the battery cell BC may be removed.

[0040] While the battery cells BC are being charged and discharged, they can be squeezed by the squeezing plates. By uniformly squeezing the battery cells BC, air traps and lithium plating can be prevented, and the uniformity of the SEI film can be improved. Battery cells with a uniform SEI film can have a relatively short charge or discharge time.

[0041] A battery cell BC is a basic unit of a lithium-ion battery (i.e., a secondary battery). The battery cell BC may be a pouch-type battery cell. The battery cell BC may include a pouch case PC and an electrode assembly within the pouch case PC. The electrode assembly within the pouch case PC includes a positive electrode, a negative electrode, and a separator between the positive and negative electrodes. The positive electrode may include a positive electrode tab connected to one of the electrode leads EL, and the negative electrode may include a negative electrode tab connected to one of the other electrode leads EL.

[0042] The bag housing PC can be provided by performing a forming process and a sealing process on a bag film. The bag film may include an inner resin layer, a metal layer, and an outer resin layer. The inner resin layer may have thermal adhesive properties to allow the bag film to be sealed. The inner resin layer may include, for example, a polyolefin-based material. The metal layer may include an alloy of iron, carbon, chromium, and manganese, an alloy of iron, chromium, and nickel, or aluminum.

[0043] The electrode assembly may be, but is not limited to, a jelly roll type electrode assembly or a stacked type electrode assembly. A jelly roll type electrode assembly includes a wound positive electrode and a negative electrode and a separator interposed between the positive electrode and the negative electrode. A stacked type electrode assembly may include a plurality of positive electrodes and a plurality of negative electrodes stacked sequentially and a plurality of separators interposed therebetween. Figure 1 The battery cell BC may be a product obtained before a formation process is performed after a pouch forming process and an electrolyte injecting process.

[0044] The positive electrode may include a positive electrode current collector and a positive electrode active material, and the negative electrode may include a negative electrode current collector and a negative electrode active material.

[0045] The thickness of the positive electrode collector may be in the range of from about 3 μm to about 500 μm. The positive electrode collector may not cause chemical changes in the secondary battery finally manufactured and may have high conductivity. The positive electrode collector may include, for example, stainless steel, nickel, titanium, baked carbon, and aluminum. The positive electrode collector may include stainless steel surface-treated with carbon, nickel, titanium, silver, or the like. The surface of the positive electrode collector may include fine uneven structures to increase the adhesion of the active material. The positive electrode collector may be in the form of a film, sheet, foil, mesh, pores, foam, non-woven fabric, or the like.

[0046] The thickness of the negative electrode current collector may be in the range of from about 3 μm to about 500 μm. The negative electrode current collector may not cause chemical changes in the secondary battery finally manufactured and may have high conductivity. The negative electrode current collector may include stainless steel, aluminum, nickel, titanium, baked carbon, and aluminum-cadmium alloy. The negative electrode current collector may include stainless steel surface-treated with carbon, nickel, titanium, silver, etc. The surface of the negative electrode current collector may include fine uneven structures to increase the adhesion of the active material. The negative electrode current collector may be in the form of a film, sheet, foil, mesh, pores, foam, non-woven fabric, etc.

[0047] The positive electrode active material is a material that can cause an electrochemical reaction. The positive electrode active material can be a lithium transition metal oxide. For example, the positive electrode active material may include: a layered compound substituted with one or more transition metals, such as lithium cobalt oxide (LiCoO2) or lithium nickel oxide (LiNiO2); a lithium manganese oxide substituted with one or more transition metals; a lithium manganese oxide having the chemical formula LiNi 1-y M y Lithium nickel-based oxide represented by O2 (herein, M is Co, Mn, Al, Cu, Fe, Mg, B, Cr, Zn or Ga, and 0.01≤y≤0.7); 1+z Ni b Mn c Co 1-(b+c+d) M d O (2-e) A represents a lithium nickel cobalt manganese compound oxide, for example, Li 1+ z Ni 1 / 3 Co 1 / 3 Mn 1 / 3 O2 or Li 1+z Ni 0.4 Mn 0.4 Co 0.2 O2 (wherein, -0.5≤z≤0.5, 0.1≤b≤0.8, 0.1≤c≤0.8, 0≤d≤0.2, 0≤e≤0.2, b+c+d<1, M is Al, Mg, Cr, Ti, Si or Y, and A is F, P or Cl); or Li 1+x M 1-y M' y PO 4-z X z An olivine-based lithium metal phosphate represented by (herein, M is a transition metal, and more specifically, Fe, Mn, Co or Ni, M' is Al, Mg or Ti, X is F, S or N, -0.5≤x≤+0.5, 0≤y≤0.5, and 0≤z≤0.1).

[0048] The negative electrode active material may include, for example, carbon, such as non-graphitizable carbon or graphite-based carbon. The negative electrode active material may include, for example, a metal composite oxide, such as Li x Fe2O3(0≤x≤1), Li x WO2(0≤x≤1) or Sn x Me 1-x Me' y O z(Here, Me is Mn, Fe, Pb, or Ge, Me' is Al, B, P, Si, an element of Group I, Group II, or Group III of the periodic table, or a halogen, 0 < x ≤ 1, 1 ≤ y ≤ 3, and 1 ≤ z ≤ 8). The negative electrode active material can include, for example, lithium metal, a lithium alloy, a silicon-based alloy, or a tin-based alloy. The negative electrode active material can include, for example, a metal oxide such as SnO, SnO2, PbO, PbO2, Pb2O3, Pb3O4, Sb2O3, Sb2O4, Sb2O5, GeO, GeO2, Bi2O3, Bi2O4, or Bi2O5. The negative electrode active material can include, for example, a conductive polymer such as polyacetylene, a Li-Co-Ni-based material, or the like.

[0049] According to an example embodiment, the driving portion 110 can include a driving plate 111 and a driving rod 116. The driving rod 116 can be configured to transmit an external driving force to the driving plate 111. The driving rod 116 can be connected to, for example, a hydraulic cylinder or a linear servo motor. The driving plate 111 can have an approximate flat plate shape. The driving plate 111 can be substantially perpendicular to the X-axis direction. The driving plate 111 can be substantially parallel to the Y-axis direction. The driving rod 116 can be configured to move the driving plate 111 in the X-axis direction.

[0050] The support portion 120 can include a support plate 121 and elastic elements 126. The support plate 121 can be spaced apart from the driving plate 111 in the X-axis direction. The support plate 121 can be substantially parallel to the driving plate 111. The support plate 121 can be substantially parallel to the Y-axis direction. The support plate 121 can be substantially perpendicular to the X-axis direction.

[0051] The elastic elements 126 can be coupled to the second surface 121S2 of the support plate 121. Axes of elasticity of the elastic elements 126 can be substantially parallel to the X-axis direction. That is, each of the elastic elements 126 can apply an elastic force in the X-axis direction to the support plate 121 in proportion to a displacement in the X-axis direction. An appropriate pressure can be applied to the battery cell BC by each of the elastic elements 126. The elastic elements 126 can be directly or indirectly connected to a sensor such as a load cell, and a pressure to be applied to the battery cell BC can be controlled based on the elastic force of the elastic elements 126.

[0052] The support plate 121 can include steps 121P. Each of the steps 121P can be spaced apart from a center of the support plate 121 (more specifically, a center in the Y-axis direction of the support plate 121). Each of the steps 121P can be on an edge of the support plate 121. Each of the steps 121P can be closer to an end in the Y-axis direction of the support plate 121 than to the center in the Y-axis direction of the support plate 121.

[0053] The distance between the end of the support plate 121 in the Y-axis direction and the step 121P may be different from the distance between the center of the support plate 121 in the Y-axis direction and the step 121P. The distance between the end of the support plate 121 in the Y-axis direction and the step 121P may be smaller than the distance between the center of the support plate 121 in the Y-axis direction and the step 121P.

[0054] The distance between the step 121P and the end of the support plate 121 close to the step 121P among the ends of the support plate 121 in the Y-axis direction may be different from the distance between the step 121P and the center in the Y-axis direction of the support plate 121. The distance between the step 121P and the end of the support plate 121 close to the step 121P among the ends of the support plate 121 in the Y-axis direction may be smaller than the distance between the step 121P and the center in the Y-axis direction of the support plate 121.

[0055] The step 121P may protrude from the first surface 121S1 of the support plate 121 in the X-axis direction. The first surface 121S1 of the support plate 121 may face the drive plate 111. The first surface 121S1 of the support plate 121 may face the pressing plate 130. Therefore, the step 121P may be configured to press the edge of the battery cell BC between the support plate 121 and the pressing plate 130 (i.e., the battery cell BC in contact with the pressing plate 130).

[0056] According to example embodiments, each of the steps 121P may include the same material as the support plate 121. For example, each of the steps 121P may be a continuous element integrally formed with the support plate 121. For example, each of the steps 121P may include aluminum. As another example, the steps 121P may include a material having a lower hardness than the support plate 121. The support plate 121P may be a silicon pad. For example, each of the steps 121P may include silicon.

[0057] During the formation process, the battery cells BC are uniformly squeezed to suppress lithium plating, so uniform pressurization of the battery cells BC is one of the key factors in the performance management of the battery cells BC. Compared with the pressure applied to the battery cells BC adjacent to the drive plate 111, the pressure applied to the battery cells BC adjacent to the support plate 121 may be relatively uneven. Therefore, the pressure applied by the support plate 121 to the edge of the battery cell BC may be lower than the pressure applied by the support plate 121 to the center of the battery cell BC. According to example embodiments, since the step 121P protrudes from the edge of the support plate 121, the battery cells BC in contact with the support plate 121 can be uniformly squeezed, and thus the reliability of manufacturing the secondary battery can be improved.

[0058] According to example embodiments, the height 122H of each of the steps 121P may be in the range of about 0.1 mm to about 1 cm. According to example embodiments, the height 122H of each of the steps 121P may be about 0.2 mm or greater. According to example embodiments, the height 122H of each of the steps 121P may be about 0.3 mm or greater. According to example embodiments, the height 122H of each of the steps 121P may be about 0.4 mm or greater. According to example embodiments, the height 122H of each of the steps 121P may be about 0.9 mm or less. According to example embodiments, the height 122H of each of the steps 121P may be about 0.8 mm or less. According to example embodiments, the height 122H of each of the steps 121P may be about 0.7 mm or less. According to example embodiments, the height 122H of each of the steps 121P may be about 0.6 mm or less.

[0059] Here, the Y-axis direction may be the direction in which the pouch case PC of the battery cell BC extends. The main surface of the pouch case PC of the battery cell BC may be substantially parallel to the Y-axis direction and substantially perpendicular to the X-axis direction. The electrode leads EL of the battery cell BC may be spaced apart from each other in the Y-axis direction, but are not limited thereto.

[0060] According to example embodiments, the compression plates 130 may be interposed between the driving plate 111 and the support plate 121. Each of the compression plates 130 may be substantially parallel to the driving plate 111. Each of the compression plates 130 may be substantially perpendicular to the X-axis direction. Each of the compression plates 130 may be substantially perpendicular to the X-axis direction.

[0061] Each of the compression plates 130 may be coupled to an axis extending in the X-axis direction. Thus, when driven by the drive plate 111, the compression plates 130 may move along the axis. A plurality of battery cells BC may be inserted between the compression plates 130 and compressed by the compression plates 130, the drive plate 111, and the support plate 121.

[0062] Each of the pressing plates 130 may have an approximately flat plate shape. Therefore, each of the pressing plates 130 may not include a step. Both main surfaces of each of the pressing plates 130 may be different from the first surface 121S1 of the support plate 121 .

[0063] The battery cell formation apparatus 100 may further include a charging terminal configured to be electrically connected to the electrode leads EL of the plurality of battery cells BC. The charging terminal may be in contact with the electrode leads EL of the plurality of battery cells BC. The charging terminal may be configured to transmit external power to the plurality of battery cells BC.

[0064] (Second embodiment)

[0065] Figure 3 is a flowchart of a secondary battery manufacturing method according to example embodiments.

[0066] Figure 4 A pressure-sensitive paper according to an example embodiment is shown.

[0067] Figure 5 A pressure-sensitive paper according to an example embodiment is shown.

[0068] refer to Figures 3 to 5 In P110, a plurality of sheets of pressure-sensitive paper PSS and battery cells BC may be loaded onto the battery cell formation apparatus 100. The loading of the battery cells BC may be performed by a pick and place machine.

[0069] The pressure-sensitive paper PSS may include microcapsules containing dyes. When pressure is applied to the pressure-sensitive paper PSS, the dyes contained in the microcapsules of the pressure-sensitive paper PSS may be released due to the pressure, and characters or colors may be displayed on the pressure-sensitive paper PSS due to a reaction between the dyes and a developer on the surface of the pressure-sensitive paper PSS. Figure 4 and Figure 5 As shown, the pressure sensitive paper PSS can display either or both of a color and a character indicating the pressure applied thereto.

[0070] Next, in P120 , a formation process may be performed on the plurality of battery cells BC. As described above, the formation process of the plurality of battery cells BC may include a charge / discharge and an aging process.

[0071] Next, in P130, the formation process of the multiple battery cells BC can be evaluated. The formation process of the multiple battery cells BC can be evaluated based on the multiple sheets of pressure-sensitive paper PSS. While processing the multiple battery cells BC, the multiple sheets of pressure-sensitive paper PSS can be squeezed together with the multiple battery cells BC. Therefore, after the formation process is completed, each sheet of the multiple sheets of pressure-sensitive paper PSS can indicate the pressure applied to the surface of a corresponding one of the multiple battery cells BC. For example, Figure 5 Compared with pressure sensitive paper PSS, Figure 4 The pressure sensitive paper PSS shows a uniform pressure distribution and therefore corresponds to Figure 4 Compared with the battery cell BC of the pressure sensitive paper PSS, the expected processing corresponds to Figure 5 Pressure sensitive paper PSS for battery cell BC.

[0072] According to an example embodiment, the evaluation of the formation process may include an evaluation when uniform pressure is applied to the plurality of battery cells BC. According to an example embodiment, the evaluation of the formation process may be based on the standard deviation of the readings of the pressure-sensitive paper PSS. According to an example embodiment, the evaluation of the activation process may include comparing the standard deviation of the readings of the pressure-sensitive paper PSS with a critical standard deviation. For example, when the standard deviation of the readings of the pressure-sensitive paper PSS is less than or equal to the critical standard deviation, the resulting battery cell BC of the formation process may be determined to be a high-quality product, and when the standard deviation of the readings of the pressure-sensitive paper PSS is greater than the critical standard deviation, it may be determined to be defective.

[0073] Based on the above description, those skilled in the art will be able to easily derive an embodiment in which the pressure-sensitive paper PSS is disposed only on the battery cells BC between the support plate 121 and the pressing plate 130 .

[0074] The present invention has been described in more detail above with reference to the accompanying drawings, embodiments, etc. However, the configurations shown in the drawings or embodiments described in this specification are merely embodiments of the present invention and do not reflect all technical concepts of the present invention. Therefore, it should be understood that various equivalents and modifications will be made to replace these configurations as of the filing date of this application.

Claims

1. A battery cell formation device, comprising: a driving portion comprising a driving plate and a driving rod configured to move the driving plate in a first direction; a supporting portion including a supporting plate and an elastic member connected to the supporting plate, wherein the supporting plate is spaced apart from the driving plate in the first direction; and a plurality of pressing plates disposed between the driving portion and the support plate and configured to press a plurality of battery cells, Wherein, the support plate includes a protrusion protruding in the first direction.

2. The battery monomer formation device according to claim 1, wherein: A height of each of the protrusions in the first direction is in a range of 0.1 mm to 1.0 mm.

3. The battery monomer formation device according to claim 1, wherein: The height of each of the protrusions in the first direction is 0.6 mm or less.

4. The battery monomer formation device according to claim 1, wherein: Each of the protrusions includes the same material as the support plate.

5. The battery monomer formation device according to claim 1, wherein: Each of the protrusions includes a material different from that of the support plate.

6. The battery monomer formation device according to claim 1, wherein: The protrusion is spaced apart from the center of the support plate.

7. The battery monomer formation device according to claim 1, wherein: The protrusions are spaced apart from each other in a second direction parallel to the support plate, and The protrusion is spaced apart from a center of the support plate in the second direction.

8. The battery monomer formation device according to claim 7, wherein: A distance between an end portion of the support plate in the second direction and the protrusion is different from a distance between the protrusion and a center of the support plate in the second direction.

9. The battery monomer formation device according to claim 7, wherein: A distance between an end portion of the support plate in the second direction and the protrusion is smaller than a distance between the protrusion and a center of the support plate in the second direction.

10. The battery monomer formation device according to claim 1, wherein: Each of the pressed plates has a flat plate shape.

11. The battery cell formation device according to claim 1, wherein: Each of the pressed plates does not include a protrusion.

12. The battery cell formation device according to claim 1, wherein: A surface of each of the pressing plates has a shape different from a shape of a surface of the support plate.

13. A secondary battery formation method comprising: loading a plurality of pressure-sensitive papers and a plurality of battery cells onto a battery cell formation device; performing a formation process on the plurality of battery cells; as well as evaluating the formation process of the plurality of battery cells based on the plurality of pressure-sensitive papers, The battery cell formation device includes: a driving portion including a driving plate and a driving rod configured to move the driving plate in a first direction; and a supporting portion including a supporting plate and an elastic element connected to the supporting plate. wherein the support plate is spaced apart from the drive plate in the first direction, and The support plate includes a protrusion protruding in the first direction.

14. The chemical formation method according to claim 13, wherein: The evaluation of the forming process is performed based on a standard deviation of pressures sensed using the plurality of sheets of pressure-sensitive paper.

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