Pressing device

Abstract

The present invention may provide a pressing device including: a plurality of pad members in which a plurality of cell accommodation parts are each formed between two adjacent pad members, to press a plurality of battery cells comprising a curable electrolyte composition in a pressing direction (PD); and an elastic part comprising at least one elastic member arranged between the two adjacent pad members.

Description

pressurized device

[0001] Cross-citation with related applications

[0002] This application is based on and claims the benefit of priority from Korean Patent Application Nos. 10-2024-0024221 and 10-2025-0016760, filed with the Korean Intellectual Property Office on February 20, 2024 and February 10, 2025, respectively, the entire contents of which are incorporated herein by reference.

[0003] Technology field

[0004] The present invention relates to a pressurizing device capable of pressurizing a battery cell.

[0005] Recently, demand for mobile devices such as smartphones, tablet PCs, and wireless earphones has been increasing. Furthermore, with the development of electric vehicles, energy storage batteries, robots, and satellites in full swing, research is actively underway on high-performance secondary batteries capable of repeated charging and discharging as an energy source.

[0006] Currently commercially available secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium secondary batteries. Among these, lithium secondary batteries offer the advantages of virtually no memory effect compared to nickel-based batteries, allowing for free charging and discharging, a very low self-discharge rate, and high energy density.

[0007] Battery cells, the functional units of batteries, utilize liquid electrolytes at room temperature. These electrolytes contain flammable materials, making them vulnerable to high temperatures and flames. To address this issue, a polymer battery cell was developed that includes a curable electrolyte composition, which is liquid at room temperature, injected into the outer casing of the battery cell, followed by a curing step to ultimately form a polymer electrolyte that is solid at room temperature.

[0008] The manufacturing process of a polymer battery cell may sequentially include an injection step of injecting a curable electrolyte composition into an outer material of a battery cell, an aging step, a pre-charge step, a curing step, and a formation step.

[0009] At this time, the work of installing and dismantling jigs at each stage to secure the battery cells in the pre-charging stage, curing stage, and formation stage was required, and the time required for this slowed down the overall process speed, which resulted in lower productivity.

[0010] The present invention provides a pressurizing device capable of increasing productivity by simultaneously performing multiple steps in the manufacturing process of a polymer battery cell without installing and dismantling jigs at each step. The present invention also provides a pressurizing device capable of preventing uneven curing of a curable electrolyte composition by preventing excessive pressure from being applied, thereby preventing a chain reaction of problems resulting from uneven curing, thereby preventing a decline in battery performance.

[0011] A pressurizing device according to one embodiment of the present invention may be for pressurizing a battery cell including a curable electrolyte composition. The pressurizing device according to one embodiment of the present invention may include a plurality of pad members each having a plurality of cell receiving portions formed between two adjacent pad members to pressurize a plurality of battery cells including a curable electrolyte composition in a pressing direction (PD); and an elastic member comprising at least one elastic member provided between the two adjacent pad members.

[0012] In a pressurizing device according to one embodiment of the present invention, the plurality of elastic parts corresponding to the plurality of pad members can all form the same elastic coefficient (k).

[0013] In a pressurizing device according to one embodiment of the present invention, the elastic modulus (k) may be within a range of 300 N / mm to 1,500 N / mm.

[0014] In a pressurizing device according to one embodiment of the present invention, the number, length, and elastic modulus (k) of at least one elastic member constituting one elastic member among the plurality of elastic members may be the same as the number, length, and elastic modulus of at least one elastic member constituting another elastic member among the plurality of elastic members.

[0015] In a pressurizing device according to one embodiment of the present invention, a pressing force (P) is applied in the pressing direction (PD), which is the stacking direction of the plurality of pad members, so that an elastic force by the elastic portion acts on the plurality of pad members, and the plurality of elastic portions can be pressed with the same pressure.

[0016] In a pressurizing device according to one embodiment of the present invention, the spacing between each cell receiving portion formed in plurality may be the same.

[0017] In a pressurized device according to one embodiment of the present invention, the curable electrolyte composition can be cured by heating.

[0018] In a pressurizing device according to one embodiment of the present invention, a first pressing force (P1) is applied to the plurality of pad members so that an elastic force by the elastic part acts before the curable electrolyte composition is cured, and a pressing direction thickness (CL) of one battery cell accommodated in one cell accommodation unit may be equal to a pressing direction length (SL) of all elastic members constituting the elastic part.

[0019] In a pressurizing device according to one embodiment of the present invention, after the curable electrolyte composition is cured, a second pressing force (P2) is applied so that an elastic force by an elastic member acts on the plurality of pad members, and a pressing direction thickness (CL) of one battery cell accommodated in one cell accommodation unit may be equal to a pressing direction length (SL) of all elastic members constituting the elastic member.

[0020] In one embodiment of the present invention, a pressurizing device may have R greater than 1 according to the following equation 1.

[0021] [Formula 1]

[0022] R = P2 / P1

[0023] In the above formula 1, P1 is a first pressing force applied to the plurality of pad members so that an elastic force by the elastic part acts on the plurality of pad members before the curable electrolyte composition is cured, and P2 is a second pressing force applied to the plurality of pad members so that an elastic force by the elastic part acts on the plurality of pad members after the curable electrolyte composition is cured.

[0024] In a pressurizing device according to one embodiment of the present invention, a pressurizing state for each of the plurality of battery cells of the plurality of pad members can be maintained while changing from the first pressurizing force (P1) to the second pressurizing force (P2).

[0025] A pressurizing device according to one embodiment of the present invention further includes a guide bar that guides movement of the plurality of pad members, and a pad member to which a pressurizing force is applied among the plurality of pad members can slide along the guide bar.

[0026] In a pressurizing device according to one embodiment of the present invention, the plurality of pad members may further include a plurality of holes through which the guide bar passes.

[0027] In a pressurizing device according to one embodiment of the present invention, the guide bar can penetrate the at least one elastic member.

[0028] In a pressurizing device according to one embodiment of the present invention, each of the plurality of pad members may independently include a heat transfer material having a thermal conductivity of 10 W / m·K or more.

[0029] The present invention improves productivity by speeding up the manufacturing process of polymer battery cells by performing multiple steps simultaneously with a single device, without installing and dismantling jigs at each step. By preventing excessive pressure from being applied, the present invention prevents uneven curing of the curable electrolyte composition, thereby preventing a chain reaction of problems resulting from uneven curing, thereby deteriorating battery performance.

[0030] The drawings shown in the present invention are according to embodiments of the present invention, and the ratios of the width, width, or thickness (or height) of each component are for the purpose of explaining the present invention in detail, and these ratios may differ from the actual ones. In addition, in the coordinate system shown in the drawings, each axis may be perpendicular to each other, and the direction pointed by the arrow may be the + direction, and the direction opposite to the direction pointed by the arrow (the direction rotated by 180 degrees) may be the - direction.

[0031] FIG. 1 and FIG. 2 are plan views illustrating at least a portion of a pressurizing device according to an embodiment of the present invention (with pressurizing force applied).

[0032] FIG. 3 is a perspective view illustrating at least a portion of a pressurizing device according to an embodiment of the present invention (in a state where no pressurizing force is applied).

[0033] FIG. 4 is a perspective view illustrating at least a portion of a pressurizing device according to an embodiment of the present invention (with pressurizing force applied).

[0034] Before proceeding with a detailed description of the present invention, it should be noted that terms and words used in this specification and claims may not be interpreted solely based on their conventional or dictionary meanings. Furthermore, inventors should interpret terms and concepts in accordance with the technical spirit of the present invention, based on the principle that the inventor can appropriately define the concepts of terms to best explain his or her invention. The embodiments described in this specification and the configurations depicted in the drawings represent only the most preferred embodiments of the present invention and may not represent all of the technical spirit of the present invention. Therefore, various equivalents and modifications may be substituted for them at the time of filing of the present invention.

[0035] The same reference numbers or symbols in each drawing attached to this specification may indicate parts or components that perform substantially the same functions. For convenience of explanation and understanding, the same reference numbers or symbols may be used in different embodiments. In other words, even if components with the same reference numbers are depicted in multiple drawings, they may not all represent a single embodiment.

[0036] In the following description, singular expressions include plural expressions unless the context clearly indicates otherwise. Terms such as "comprise" or "comprises" are intended to specify the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but are to be understood as not excluding in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0037] In addition, in the description below, expressions such as upper, upper, lower, lower, side, front, and rear are expressed based on the direction shown in the drawing, and may be expressed differently if the direction of the object is changed.

[0038] Additionally, terms including ordinal numbers, such as "first," "second," etc., may be used in this specification and claims to distinguish between components. These ordinal numbers may be used to distinguish identical or similar components from each other, and the use of these ordinal numbers should not be interpreted in a limited manner. For example, components associated with these ordinals should not be interpreted in a restricted manner, such as in the order of use or arrangement, based on their numbers. If necessary, each ordinal number may be used interchangeably.

[0039] The term room temperature used in this specification refers to the natural temperature that is not heated or cooled, and may mean, for example, any temperature within the range of 10°C to 30°C, for example, about 15°C or higher, about 18°C ​​or higher, about 20°C or higher, about 23°C or higher, about 27°C or lower, or 25°C. Unless specifically specified herein, the unit of temperature is Celsius (°C). In addition, among the physical properties mentioned in this specification, if the measurement temperature affects the physical property, the physical property may be measured at 25°C unless specifically specified otherwise.

[0040] In this specification, the term "battery" may be used interchangeably with "cell." Furthermore, the terms "battery" and "cell" may collectively refer to a battery cell, which is a unit thereof, or a battery module or battery pack containing a battery cell.

[0041] The term battery cell used in this specification may be a concept that includes a state of a finished product (i.e., a product capable of generating electrical energy) that can ultimately perform the functional unit of a battery, as well as a state of a semi-finished product that only has an external appearance during the manufacturing process for manufacturing a finished product.

[0042] The present invention can provide a pressurizing device (10) that can increase productivity by increasing process speed by performing multiple steps at once with a single device without installing and dismantling jigs at each step in the manufacturing process of a polymer battery cell. The present invention can provide a pressurizing device (10) that can prevent the problem of uneven curing of a curable electrolyte composition by preventing excessive application of pressure, and can prevent a chain reaction of problems due to uneven curing, resulting in a decrease in battery performance.

[0043] FIG. 1 and FIG. 2 are plan views illustrating at least a portion of a pressurizing device (10) according to an embodiment of the present invention (with pressurizing applied). FIG. 3 is a perspective view illustrating at least a portion of a pressurizing device (10) according to an embodiment of the present invention (without pressurizing applied). FIG. 4 is a perspective view illustrating at least a portion of a pressurizing device (10) according to an embodiment of the present invention (with pressurizing applied).

[0044] The pressurizing device (10) can pressurize the battery cell (200). The battery cell (200) can include a curable electrolyte composition. The curable electrolyte composition can be liquid at room temperature. The curable electrolyte composition can be cured by heating. Alternatively, the curable electrolyte composition can be cured by at least one of heating and pressurization. The curable electrolyte composition can be cured by gelation through a crosslinking or polymerization reaction under curing conditions.

[0045] The cured curable electrolyte composition may be referred to as a gelled electrolyte, and the gelled electrolyte may serve as an electrolyte that moves one or more of an electron transport material (lithium or sodium) and electrons in a battery cell (200).

[0046] The curable electrolyte composition may include an organic solvent and a polymer (e.g., a polymer or oligomer). The curable electrolyte composition may include an organic solvent, an electron transfer agent salt, a polymer, and a crosslinking initiator.

[0047] The organic solvent included in the curable electrolyte composition may include at least one selected from a carbonate solvent, an ether solvent, and an ester solvent. The carbonate solvent may include at least one selected from a cyclic carbonate solvent and a linear carbonate solvent. The cyclic carbonate solvent may include, for example, at least one selected from ethylene carbonate (EC), propylene carbonate (PC), 1,2-butylene carbonate (1,2-BC), 2,3-butylene carbonate (2,3-BC), 1,2-pentylene carbonate (1,2-PTC), 2,3-pentylene carbonate (2,3-PTC), and vinylene carbonate (VC). The linear carbonate solvent may include, for example, one or more selected from methyl carbonate, ethyl carbonate, dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), ethylmethyl carbonate (EMC), methylpropyl carbonate (MPC), and ethylpropyl carbonate (EPC).The ether solvent may include at least one selected from dimethyl ether, diethyl ether, dipropyl ether, methylethyl ether, methylpropyl ether, and ethylpropyl ether. The ester solvent may include at least one selected from linear ester solvents and cyclic ester solvents. For example, the linear ester compound may include at least one selected from methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, and butyl propionate. Additionally, for example, the cyclic ester compound may include one or more selected from, for example, gamma-buturolactone, gamma-valerolactone, gamma-caprolactone, sigma-valerolactone, and epsilon-caprolactone.

[0048] The organic solvent of the curable electrolyte composition may include a cyclic carbonate solvent and a linear carbonate solvent. For example, the organic solvent may include ethylene carbonate (EC) and ethyl methyl carbonate (EMC). The volume of the linear carbonate solvent in the curable electrolyte composition may be greater than the volume of the cyclic carbonate solvent, and the volume may be based on 25°C.

[0049] The electron transport material salt included in the curable electrolyte composition may be a lithium salt or a sodium salt, and the anion of the electron transport material salt is F - , Cl - , Br - , I - , NO3 - , N(CN)2 - , BF4 - , ClO4 - , PF6 - , (CF3)2PF4 - , (CF3)3PF3 - , (CF3)4PF2 - , (CF3)5PF - , (CF3)6P - , CF3SO3 - , CF3CF2SO3 - , (CF3SO2)2N - (FSI - ), (FSO2)2N - , CF3CF2(CF3)2CO - , (CF3SO2)2CH - , (SF5)3C - , (CF3SO2)3C - , CF3(CF2)7SO3 - , CF3CO2 - , CH3CO2 - , SCN - and (CF3CF2SO2)2N - It may include one or more selected from. The electron transfer material salt is not particularly limited, but may have a concentration of, for example, 0.1 M to 2 M, 0.3 M to 1.5 M or 0.5 M to 1.2 M at 25°C, taking into account appropriate conductivity and viscosity.

[0050] The polymer included in the curable electrolyte composition may be crosslinkable. The polymer is not particularly limited, but may include one or more of a fluorine-based polymer, a (meth)acryl-based polymer, and a carbonate-based polymer. The polymer may include one or more of a fluorine-based polymer and a carbonate-based polymer.

[0051] The fluorine-based polymer may include, for example, a PVDF-based polymer containing a vinylidene fluoride unit, and the PVDF-based polymer may include, for example, one or more selected from PVDF (Polyvinylidene fluoride), PVDF-HFP (Polyvinylidene fluoride-co-hexafluoropropylene), PVDF-TFE (Polyvinylidene fluoride-co-tetrafluoroproethylene), PVDF-CTFE (Polyvinylidene fluoride-co-chloro trifluoro ethylene), and PVDFTrFE (Polyvinylidene fluoride-co-trifluoroproethylene). The acrylic-based polymer may be derived from a monomer containing a (meth)acrylate functional group at a terminal. The carbonate-based polymer may be derived from a monomer containing a carbonate functional group at a terminal.

[0052] Taking viscosity and stability after curing into consideration, the polymer may be included in an amount of 0.1 wt% to 50 wt%, 0.2 wt% to 45 wt%, 0.3 wt% to 40 wt%, 0.4 wt% to 35 wt%, 0.5 wt% to 30 wt%, 0.6 wt% to 25 wt%, 0.7 wt% to 20 wt%, 0.8 wt% to 15 wt%, or 0.9 wt% to 10 wt% relative to the total weight of the curable electrolyte composition (240).

[0053] The crosslinking initiator included in the curable electrolyte composition may include a thermal initiator such as AIBN (Azobisisobutyronitrile) or a peroxide initiator such as benzoyl peroxide.

[0054] The curable electrolyte composition may contain additives as needed.

[0055] The additive may include, for example, a sulfate-based compound to minimize decomposition of the curable electrolyte composition. The sulfate-based compound may include, for example, one or more of methylene sulfate (MSA), ethylene sulfate (ESA), trimethylene sulfate (TMS), and methyl trimethylene sulfate (MTMS).

[0056] The additive may include, for example, a phosphate compound to aid in the formation of a solid electrolyte interphase (SEI) film. The phosphate compound may include, for example, one or more of lithium difluoro (bisoxalato) phosphate, lithium difluoro phosphate, tetramethyltrimethyl silyl phosphate, trimethyl silyl phosphate, and tris(2,2,2-trifluoroethyl) phosphate.

[0057] The additive may include, for example, a sultone-based compound that may aid in the formation of an SEI film. The sultone-based compound may include, for example, one or more of 1,3-propane sultone (PS), 1,4-butane sultone, ethensultone, 1,3-propene sultone (PRS), 1,4-butene sultone, and 1-methyl-1,3-propene sultone.

[0058] The additive may include, for example, a carbodiimide compound to minimize the effects of moisture. The carbodiimide compound may include, for example, dicyclohexylmethanediimine (DCC).

[0059] The battery cell (200) may include an electrode assembly and a curable electrolyte composition embedded within an outer case. The electrode assembly includes a cathode and an anode, and may further include a separator if necessary. The anode of the electrode assembly may be electrically connected to a cathode tab extending from the outer case, and the cathode of the electrode assembly may be electrically connected to a cathode tab extending from the outer case.

[0060] The pressurizing device (10) can heat the battery cell (200) as needed and may include a heat source for heating. The heat source may be provided in the pad member (100) described later.

[0061] The plurality of pad members (100) may each include a heat-conducting material having a thermal conductivity of 10 W / m·K or more to more uniformly transfer heat to the battery cell (200) and minimize external deformation. Here, the heat-conducting material may be solid at room temperature, and the thermal conductivity may be measured based on, for example, ISO 22007-2. The heat-conducting material may include a metal material including, for example, aluminum (Al). The heat transfer material may, in other examples, have a thermal conductivity of, for example, 20 W / m·K or more, 30 W / m·K or more, 40 W / m·K or more, 50 W / m·K or more, 60 W / m·K or more, 70 W / m·K or more, 80 W / m·K or more, 90 W / m·K or more, 100 W / m·K or more, 110 W / m·K or more, 120 W / m·K or more, 130 W / m·K or more, 140 W / m·K or more, or 150 W / m·K or more. The upper limit of the thermal conductivity of the heat transfer material is not particularly limited, but may be, for example, 500 W / m·K or less, 450 W / m·K or less, 400 W / m·K or less, 350 W / m·K or less, 300 W / m·K or less, or 250 W / m·K or less.

[0062] The pressurizing device (10) can heat the battery cell (200) from room temperature to a predetermined temperature. The process of heating to a temperature higher than room temperature and / or maintaining the temperature at the elevated temperature may be referred to as heating. The predetermined temperature may be a temperature suitable for curing or activating the curable electrolyte composition included in the battery cell (200).

[0063] The curable electrolyte composition can be injected into an outer shell containing an electrode assembly, which is sealed except for the injection port (injection step). After this, the composition is maintained at room temperature for a predetermined period of time (aging step), and a pre-charge can be performed (pre-charge step). After this, a curing step can be performed.

[0064] The curable electrolyte composition can be cured through a curing step. As the curable electrolyte composition is cured through the curing step, the interior of the battery cell (200) exterior material can be filled with a gelled electrolyte. The curing step can be performed by heating the curable electrolyte composition. Here, the predetermined temperature can be a temperature at which the curable electrolyte composition can initiate a crosslinking or polymerization reaction due to heat to perform gelation while minimizing side reactions. For example, the predetermined temperature in the curing step can be about 40°C to 80°C or about 50°C to 65°C. The pressurizing device (10) can heat the battery cell (200) during this process.

[0065] A formation step may be performed on a battery cell (200) filled with a gelled electrolyte, which is a curable electrolyte composition that has been cured inside an outer case through a curing step. In the formation step, the battery cell (200) filled with the gelled electrolyte may be activated by imparting electrical properties. The formation step may include stabilization work, inspection, and evaluation after activation. In the formation step, the battery cell (200) filled with the gelled electrolyte may be pressurized to remove gases generated during the activation process or for other reasons. To achieve the above purpose, the pressurizing force required in the formation step needs to be sufficiently high, which may mean higher than the pressurizing force in the curing step.

[0066] That is, the pressing force required in each of the formation stage and the hardening stage is different, and the purpose of the pressing device (10) of the present invention is to switch from the hardening stage to the formation stage without separate jig installation and disassembly work.

[0067] Meanwhile, the formation step can be performed simultaneously with pressurization and heating for faster activation, and the pressurization device (10) can apply a pressurizing force while heating the battery cell (200) during this process.

[0068] The pressurizing device (10) may include a plurality of pad members (100) in which a plurality of cell receiving portions (100G) are formed between two adjacent pad members (100) to pressurize a plurality of battery cells (200) including a curable electrolyte composition in a pressing direction (PD).

[0069] The cell receiving portion (100G) may be a space formed between two adjacent pad members (100) arranged side by side with a predetermined gap therebetween. One battery cell (200) among a plurality of battery cells (200) may be received in the cell receiving portion (100G).

[0070] A plurality of pad members (100) are arranged in a stacked manner with each pad member (100) spaced apart from each other, and a cell receiving portion (100G) is formed between them, and one battery cell (200) can be received in each formed cell receiving portion (100G) (see FIGS. 1 and 3).

[0071] A plurality of pad members (100) may be stacked side by side in the pressing direction (PD). By stacking a plurality of pad members (100) side by side in the pressing direction (PD), it is advantageous that the same pressure is applied to the battery cells (200) accommodated in each of the plurality of cell receiving portions (100G) by the pressing force (P) applied in the pressing direction (PD). If different pressures are applied to the battery cells (200) accommodated in each of the plurality of cell receiving portions (100G), the curing may be performed unevenly in the curing step for each battery cell (200), and in the formation step, the degree of activation may vary for each battery cell (200), which may make it difficult to produce a battery cell (200) product having uniform quality. That is, if the same pressure is applied to the battery cells (200) accommodated in each of the plurality of cell receiving portions (100G), this problem is prevented, thereby making it advantageous to produce a battery cell (200) product having uniform quality.

[0072] In the plurality of pad members (100) before pressurization, the gap between two adjacent pad members (100) may be greater than the thickness (CL) in the pressing direction of the battery cell (200). That is, since the width of the cell receiving portion (100G) in the pressing direction (PD) is greater than the thickness (CL) in the pressing direction of the battery cell (200), the battery cell (200) can be easily accommodated in the cell receiving portion (100G).

[0073] The pressurizing device (10) may include an elastic member (300) composed of at least one elastic member (310) provided between two adjacent pad members (100). The elastic member (300) may be composed of a plurality of elastic members (310) for structural stability during pressurization. For example, the elastic member (300) may be composed of elastic members (310) provided at each corner portion of the pad member (100) (see FIGS. 3 and 4).

[0074] The pressurizing device (10) may include a plurality of elastic members (300) corresponding to a plurality of pad members (100). To further enhance structural stability during pressurization, each of the plurality of elastic members (300) may be composed of elastic members (310) of the same number and length. The elastic members (310) may be, for example, springs.

[0075] A plurality of elastic members (300) according to a plurality of pad members (100) may all have the same elastic coefficient (k). For example, the elastic modulus (k) is 300 N / mm or more, 310 N / mm or more, 320 N / mm or more, 330 N / mm or more, 340 N / mm or more, 350 N / mm or more, 360 N / mm or more, 370 N / mm or more, 380 N / mm or more, 390 N / mm or more, or 400 N / mm or more, or 1,500 N / mm or less, 1,400 N / mm or less, 1,300 N / mm or less, 1,200 N / mm or less, 1,100 N / mm or less, 1,000 N / mm or less, 950 N / mm or less, 900 N / mm or less, 850 N / mm or less, 800 N / mm or less, 750 N / mm or less, 700 N / mm or less, 650 N / mm or less, or 600 N / mm or less. The elastic modulus (k) may be within a range formed by selecting the upper and lower limits described above, and may be a range that takes into account both aspects of sufficient pressing force and minimizing the phenomenon of the curable electrolyte composition being pushed due to pressing. As a specific example, the elastic modulus (k) may be 400 N / mm or more and 600 N / mm or less. Since all of the plurality of elastic parts (300) have the same elastic modulus (k), when battery cells (200) of the same thickness are arranged in each of the plurality of cell receiving parts (100G), the pressing force (P) applied in the pressing direction (PD) is the same, so when battery cells (200) of the same thickness are accommodated in each of the plurality of cell receiving parts (100G), it is advantageous in that the same pressure is applied to each battery cell (200).

[0076] Since the elastic coefficient (k) of the elastic portion (300) is determined by the elastic coefficient (k) of at least one elastic member (310) constituting the elastic portion (300), it is preferable that the number, length, and elastic coefficient (k) of the elastic members (310) constituting each elastic portion (300) in the plurality of elastic portions (300) are all the same. That is, the number, length, and elastic coefficient (k) of at least one elastic member (310) constituting one elastic portion (300) among the plurality of elastic portions (300) may be the same as the number, length, and elastic coefficient (k) of at least one elastic member (310) constituting another elastic portion (300) among the plurality of elastic portions (300).

[0077] In this specification, the lengths of the elastic members (310) being the same may mean that they are substantially the same. For example, the ratio of the difference in length between one elastic member (310) and another elastic member (310) based on the length of one elastic member (310) may be within 5%.

[0078] In this specification, the fact that the elastic moduli (k) of the elastic members (310) are the same may mean that they are substantially the same. For example, the ratio of the difference in the elastic modulus (k) between one elastic member (310) and another elastic member (310) based on the elastic modulus (k) of one elastic member (310) may be within 5%.

[0079] When a pressing force (P) is applied to a plurality of pad members (100) in a pressing direction (PD), which is the stacking direction of the plurality of pad members (100), the plurality of elastic members (300) can be pressed with the same pressure so that the elastic force by the elastic members (300) can act, which ultimately means that the same pressure can be applied to the battery cells (200) each accommodated in the plurality of cell accommodation units (100G).

[0080] When the elastic members (310) constituting the elastic part (300) are all the same when a pressing force (P) is applied in the pressing direction (PD), the spacing between each cell receiving portion (100G) can be maintained the same, and if the thickness of the battery cells (200) each received in the plurality of cell receiving portions (100G) is also the same, the same pressure can be applied to each battery cell (200).

[0081] The manufacturing process of a polymer battery cell requires a step of curing a curable electrolyte composition, and this step requires a different temperature and pressure from the formation step. Therefore, in the past, different jigs were used in the curing step and the formation step. As a result, while a jig used in the curing step was installed, curing was performed, the jig was dismantled, and then a jig used in the formation step was installed, activation, etc. were performed, and the jig was dismantled to manufacture a battery cell (200) product, the pressurizing device (10) of the present invention can respond to the pressurizing force required in each of the curing step and the formation step by only adjusting the pressurizing force (P) applied in the pressurizing direction (PD), and thus the process of installing and dismantling the jig can be largely omitted.

[0082] In particular, since the pressing force (P) applied to one pad member (100) due to the elastic portion (300) is transmitted to the adjacent pad members (100) in a chain, the entire pressing force (P) can be controlled by controlling only the pressing force (P) of the pad members (100) located at both ends among the plurality of pad members (100). This means that there is no need to individually adjust the spacing of each pad member (100) in order to provide a uniform pressing force (P) to each battery cell (200), and it may also mean that only a tensile force to spread the plurality of pad members (100) needs to be applied when mounting the battery cell (200) on or removing it from the pressing device (10).

[0083] Since the pressurizing device (10) can be used to pressurize the battery cells (200) during the manufacturing process of the polymer battery cell, the pressurizing device (10) can be used in the pre-charging step, the curing step, and the formation step. In addition, the pressurizing device (10) can also be used in cases where it is necessary to align a plurality of battery cells (200) to perform the same process even if no pressurizing force is applied to the battery cells (200). Therefore, the pressurizing device (10) can be used sequentially in the pre-charging step, the curing step, and the formation step, which are performed sequentially, and by installing it in the pre-charging step and then dismantling it in the formation step, the process speed can be increased, thereby improving productivity.

[0084] When performing the process in a conventional manner, the time required for the installation and disassembly of the jig at each step is compared to the time required for using the pressurizing device (10), and when using the pressurizing device (10), the time can be shortened by approximately 36% (based on 100 medium- to large-sized pouch-type battery cells). In addition, while the conventional method requires installing and disassembling the jig three or more times, the pressurizing device (10) of the present invention requires installing and disassembling it only once, so convenience can also be improved.

[0085] Before the curable electrolyte composition is cured, a first pressing force (P1) may be applied to the plurality of pad members (100) so that the elastic force of the elastic member (300) acts. At this time, the pressing direction thickness (CL) of one battery cell (200) accommodated in one cell accommodation portion (100G) may be equal to the pressing direction length (SL) of all elastic members (310) constituting the elastic member (300). For example, the first pressing force (P1) may be 300 kgf or less, 290 kgf or less, 280 kgf or less, 270 kgf or less, 260 kgf or less, 250 kgf or less, 240 kgf or less, 230 kgf or less, 220 kgf or less, 210 kgf or less, or 200 kgf or less. The lower limit of the first pressing force (P1) is not particularly limited, but may exceed 0 kgf, and the first pressing force (P1) may be within a range formed by selecting the upper and lower limits described above. That is, the plurality of pad members (100) pressurize the battery cell (200) by the first pressing force (P1), and at the same time, pressurize the elastic member (300), so that the elastic force by the elastic member (300) acts on the pad member (100), thereby preventing excessive pressing force from being applied to the battery cell (200). Through this, the pressing device (10) can prevent the problem of the curable electrolyte composition being unevenly cured, and thus can prevent the performance degradation of the battery caused by uneven curing of the curable electrolyte composition.

[0086] Before the curable electrolyte composition is cured means before the curable electrolyte composition reaches the target curing rate. In the present specification, the curing rate is expressed as a percentage of the content ratio (weight ratio) of the cured curable electrolyte composition compared to the content of the curable electrolyte composition before curing, and although not particularly limited, it may be measured based on the ratio of multiple bonds by FT-IR (Fourier-transform infrared spectroscopy) or by a cell scanning method. In other words, before the curable electrolyte composition is cured may mean the curing stage.

[0087] The pressurizing device (10) can set the first pressurizing force (P1) applied in the curing step to a degree that holds the outer shape of the battery cell (200) or a degree that presses it to fix it. When the pad member (100) begins to apply pressure to the battery cell (200), the elastic member (300) can simultaneously apply the resulting elastic force to the pad member (100).

[0088] After the curable electrolyte composition is cured, a second pressing force (P2) may be applied to the plurality of pad members (100) so that the elastic force of the elastic member (300) acts. At this time, the pressing direction thickness (CL) of one battery cell (200) accommodated in one cell accommodation portion (100G) may be equal to the pressing direction length (SL) of all elastic members (310) constituting the elastic member (300). For example, the second pressing force (P2) may be 300 kgf or less, 290 kgf or less, 280 kgf or less, 270 kgf or less, 260 kgf or less, 250 kgf or less, 240 kgf or less, 230 kgf or less, 220 kgf or less, 210 kgf or less, or 200 kgf or less. The lower limit of the second pressing force (P2) is not particularly limited, but may exceed 0 kgf, and the second pressing force (P2) may be within a range formed by selecting the upper and lower limits described above. That is, the plurality of pad members (100) pressurize the battery cell (200) by the second pressing force (P2), and at the same time, pressurize the elastic member (300), so that the elastic force by the elastic member (300) acts on the pad member (100) to prevent excessive pressing force from being applied to the battery cell (200). Through this, the pressing device (10) can prevent the problem of the curable electrolyte composition being unevenly cured, and can prevent the performance degradation of the battery that occurs as a chain of problems due to uneven curing of the curable electrolyte composition.

[0089] After the curable electrolyte composition has been cured means after the curable electrolyte composition has reached the desired curing rate. In other words, after the curable electrolyte composition has been cured may mean the formation stage.

[0090] The pressurizing device (10) may have R according to the following formula 1 as being greater than 1, 1.1 or more, 1.2 or more, 1.3 or more, 1.4 or more, 1.5 or more, 1.6 or more, 1.7 or more, 1.8 or more, 1.9 or more, or 2 or more. In addition, R according to the following formula 1 is not particularly limited, but may be 5 or less, 4.9 or less, 4.8 or less, 4.7 or less, 4.6 or less, 4.5 or less, 4.4 or less, 4.3 or less, 4.2 or less, 4.1 or less, or 4 or less. In addition, R according to the following formula 1 may be within a range formed by selecting the above-mentioned upper and lower limits. That is, the pressurizing device (10) may be set so that the pressurizing force in the formation step (i.e., the second pressurizing force) is higher than the pressurizing force in the hardening step (i.e., the first pressurizing force) within the above range. The pressurizing device (10) can apply a second pressurizing force (P2), which is a higher pressurizing force, while applying a first pressurizing force (P1) to the battery cell (200), by having the elastic part (300) act as a buffer of the pressurizing force, thereby increasing the process speed and improving productivity by performing multiple steps at once with one device.

[0091] [Formula 1]

[0092] R = P2 / P1

[0093] In Equation 1, P1 is a first pressing force (P1) applied to the plurality of pad members (100) so that an elastic force by the elastic part (300) acts on the plurality of pad members (100) before the curable electrolyte composition is cured, and P2 is a second pressing force (P2) applied to the plurality of pad members (100) so that an elastic force by the elastic part (300) acts on the plurality of pad members (100) after the curable electrolyte composition is cured.

[0094] As the pressure changes from the first pressure (P1) to the second pressure (P2), the pressure state for each of the plurality of battery cells (200) of the plurality of pad members (100) can be maintained. That is, the pressure device (10) can be used continuously at least in the curing step and the formation step without being installed and dismantled at each step, thereby increasing the process speed and improving productivity.

[0095] The pressurizing device (10) may include a guide bar (400) that guides the movement of a plurality of pad members (100). Among the plurality of pad members (100), a pad member (100) to which a pressurizing force (P) is applied may slide along the guide bar (400) (see FIGS. 3 and 4).

[0096] The plurality of pad members (100) may further include a plurality of holes (100H) through which the guide bar (400) is provided to pass. The guide bar (400) may pass through the plurality of holes (100H) provided in each pad member (100) of the plurality of pad members (100).

[0097] The guide bar (400) can penetrate at least one elastic member (310). The guide bar (400) can penetrate a hole (100H) provided in one pad member (100), an elastic member (310) at a corresponding position, and a hole (100H) provided in another pad member (100) and at a corresponding position.

[0098] Through this, the pressurizing device (10) can be implemented so that the elastic part (300) acts as a buffer of the pressurizing force, and since a plurality of pad members (100) are provided to be movable on the guide bar (400), when a specific pressurizing force (P) is applied to one side (or both sides) of the pressurizing device (10), each pad member (100) moves and receives the same pressure.

[0099] The pressurization device (10) according to one embodiment of the present invention can be widely applied to green technology fields such as electric vehicles, battery charging stations, and other battery-powered solar and wind power generation. Furthermore, the pressurization device (10) according to one embodiment of the present invention can be applied to eco-friendly electric vehicles or hybrid vehicles, etc., which prevent climate change by suppressing air pollution and greenhouse gas emissions.

[0100] While various embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and it will be apparent to those skilled in the art that various modifications and variations are possible without departing from the technical spirit of the present invention as set forth in the claims. Furthermore, the embodiments described above may be implemented by deleting some components, and the embodiments may be implemented in combination with each other.

[0101] [Explanation of symbols]

[0102] 10... pressurized device 100... pad absence

[0103] 100G... cell receiving area 100H... hole

[0104] 200... battery cells 300... elastic parts

[0105] 310... elastic member 400... guide bar

Claims

1. A plurality of pad members having a plurality of cell receiving portions formed between two adjacent pad members to pressurize a plurality of battery cells including a curable electrolyte composition in a pressing direction (PD); and A pressurizing device comprising an elastic member comprising at least one elastic member provided between two adjacent pad members.

2. In paragraph 1, A pressurizing device in which a plurality of elastic parts corresponding to the plurality of pad members all form the same elastic coefficient (k).

3. In paragraph 2, A pressurizing device having an elastic modulus (k) within a range of 300 N / mm to 1,500 N / mm.

4. In paragraph 2, A pressurizing device in which the number, length and elastic modulus (k) of at least one elastic member constituting one elastic member among the plurality of elastic members are the same as the number, length and elastic modulus of at least one elastic member constituting another elastic member among the plurality of elastic members.

5. In paragraph 2, A pressing force (P) is applied in the pressing direction (PD), which is the stacking direction of the plurality of pad members, so that the elastic force by the elastic part acts on the plurality of pad members, A pressurizing device in which the plurality of elastic members are pressurized with the same pressure.

6. In paragraph 5, The spacing between each cell receiving portion formed by the above plurality is the same as the pressure device.

7. In paragraph 1, A pressurized device in which the above curable electrolyte composition is cured by heating.

8. In paragraph 7, Before the above-mentioned curable electrolyte composition is cured, a first pressing force (P1) is applied to the plurality of pad members so that the elastic force by the elastic part acts on them, A pressurizing device in which the thickness (CL) in the pressing direction of one battery cell accommodated in one of the above cell accommodation portions is equal to the length (SL) in the pressing direction of all elastic members constituting the elastic portion.

9. In paragraph 7, After the above-mentioned curable electrolyte composition is cured, a second pressing force (P2) is applied so that an elastic force by an elastic part acts on the plurality of pad members, A pressurizing device in which the thickness (CL) in the pressing direction of one battery cell accommodated in one of the above cell accommodation portions is equal to the length (SL) in the pressing direction of all elastic members constituting the elastic portion.

10. In paragraph 7, A pressurized device having R greater than 1 according to the following equation 1: [Formula 1] R = P2 / P1 In the above formula 1, P1 is a first pressing force applied to the plurality of pad members so that an elastic force by the elastic part acts on the plurality of pad members before the curable electrolyte composition is cured, and P2 is a second pressing force applied to the plurality of pad members so that an elastic force by the elastic part acts on the plurality of pad members after the curable electrolyte composition is cured.

11. In paragraph 10, A pressurizing device that maintains a pressurized state for each of the plurality of battery cells of the plurality of pad members as the first pressurizing force (P1) changes to the second pressurizing force (P2).

12. In paragraph 1, Further comprising a guide bar for guiding the movement of the plurality of pad members, A pressure device in which a pad member to which a pressure force is applied among the plurality of pad members slides along the guide bar.

13. In paragraph 12, A pressurizing device wherein the plurality of pad members further include a plurality of holes through which the guide bar passes.

14. In paragraph 12, The above guide bar is a pressurizing device penetrating at least one elastic member.

15. In paragraph 1, A pressurizing device in which each of the plurality of pad members independently includes a heat transfer material having a thermal conductivity of 10 W / m·K or more.

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