Battery cell heating device

Abstract

The present application can provide a battery cell heating device for heating a battery cell comprising a body portion and an electrode tab extending from the side surface of the body portion, the battery cell heating device comprising: a first jig plate for supporting one surface of the body portion; and a second jig plate for supporting the other surface of the body portion, wherein the first jig plate and / or the second jig plate surrounds the side surface of the body portion.

Description

Battery cell heating device

[0001] Cross-citation with related applications

[0002] This application is based on and claims the benefit of priority from Korean Patent Application Nos. 10-2024-0013980 and 10-2025-0011189, filed with the Korean Intellectual Property Office on January 30, 2024 and January 24, 2025, respectively, the entire contents of which are incorporated herein by reference.

[0003] Technology field

[0004] The present application relates to a battery cell heating device capable of heating or heating and 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 polymer electrolyte that is solid at room temperature, by injecting a liquid, curable electrolyte composition into the outer casing of the battery cell, followed by a curing process.

[0008] However, in the process of manufacturing a polymer battery cell, there was a problem in that the liquid electrolyte composition before curing was pushed in the direction of gravity by gravity and the curing process was performed, resulting in uneven curing of the electrolyte composition and distortion of the shape of the battery cell, which resulted in a deterioration in the performance of the battery.

[0009] In this way, in order to prevent problems caused by gravity during the process of manufacturing polymer battery cells, metal plates that pressurize both sides of the battery cell during the curing process and spacers to maintain the gap between the metal plates were used. However, this method had problems such as the battery cell being excessively pressurized, causing the electrolyte composition to protrude and the electrolyte not being properly placed between the electrodes, or conversely, not being sufficiently pressurized, causing uneven curing, making it difficult to maintain the performance of the battery.

[0010] The present application can provide a battery cell heating device that can prevent battery performance degradation caused by problems such as deformation of the battery cell due to uneven curing of a curable electrolyte composition, and chain reactions resulting from cracks. The present application can provide a battery cell heating device that can shorten the curing time required for a curable electrolyte composition to achieve a sufficient degree of curing, and increase the process speed, thereby improving productivity.

[0011] A battery cell heating device according to one embodiment of the present application may be for heating a battery cell including a main body and an electrode tab extending from a side of the main body.

[0012] A battery cell heating device according to one embodiment of the present application includes a first jig plate supporting one side of the main body and a second jig plate supporting the other side of the main body, and at least one of the first jig plate and the second jig plate may surround a side surface of the main body.

[0013] In a battery cell heating device according to one embodiment of the present application, the battery cell includes an electrode assembly and a curable electrolyte composition within a main body, and the curable electrolyte composition can be cured by heating.

[0014] In a battery cell heating device according to one embodiment of the present application, the curable electrolyte composition may include an organic solvent and a polymer.

[0015] In a battery cell heating device according to one embodiment of the present application, the organic solvent may include a cyclic carbonate-based solvent and a linear carbonate-based solvent, and the polymer may include at least one of a fluorine-based polymer and a carbonate-based polymer.

[0016] In a battery cell heating device according to one embodiment of the present application, the first jig plate includes a first side wall portion that surrounds a first area of ​​a side surface of the main body portion and a first main wall portion that surrounds one surface of the main body portion, the second jig plate includes a second side wall portion that surrounds a second area of ​​a side surface of the main body portion and a second main wall portion that surrounds the other surface of the main body portion, and the first side wall portion may further surround at least a portion of one surface of the electrode tab, and the second side wall portion may further surround at least a portion of the other surface of the electrode tab.

[0017] In a battery cell heating device according to one embodiment of the present application, the first jig plate and the second jig plate are combined to form a storage space in which a battery cell is stored, and the shape of the storage space can be configured to correspond to the outer shape of the battery cell to be stored.

[0018] In a battery cell heating device according to one embodiment of the present application, the first jig plate and the second jig plate may have a symmetrical structure.

[0019] In a battery cell heating device according to one embodiment of the present application, the storage space can satisfy R according to Equation 1 below of 1% or less.

[0020] [Formula 1]

[0021] R = V2 / V1× 100

[0022] In Equation 1, V2 is the volume of empty space within the storage space when no battery cells are stored, and V1 is the volume of empty space within the storage space when the battery cells are stored.

[0023] In a battery cell heating device according to one embodiment of the present application, a battery cell stored in the storage space is heated, and while the heating is performed, the battery cell can be fixed on the first jig plate and the second jig plate.

[0024] In a battery cell heating device according to one embodiment of the present application, a fixing member that penetrates the first jig plate and the second jig plate and connects them to each other is further included, and the fixing member can be provided in a space other than the storage space.

[0025] In a battery cell heating device according to one embodiment of the present application, a fixing member may be further included that penetrates the first jig plate and the second jig plate and connects them to each other.

[0026] In a battery cell heating device according to one embodiment of the present application, the first jig plate and the second jig plate may each independently include a heat transfer material having a thermal conductivity of 10 W / m·K or more.

[0027] The present application can prevent battery performance degradation caused by problems such as deformation of battery cells due to uneven curing of a curable electrolyte composition, and chain reactions resulting from cracks. The present application can shorten the curing time required for a curable electrolyte composition to achieve a sufficient degree of curing, and increase the process speed, thereby improving productivity.

[0028] The drawings shown in this application are according to an embodiment of this application, and the ratio of the width, width, or thickness (or height) of each component is for the purpose of explaining this application 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.

[0029] FIGS. 1 to 3 are plan views (side views) illustrating at least a portion of a battery cell heating device according to an embodiment of the present application.

[0030] FIG. 4 is a plan view illustrating at least a portion of a battery cell heating device according to another embodiment of the present application (a side view of the main body, with the electrode assembly built into the main body indicated by a dotted line).

[0031] FIG. 5 is a cross-sectional view showing at least a portion of a battery cell heating device according to another embodiment of the present application (a view of the main body seen through the XY cross-section, with the electrode assembly built into the main body indicated by a dotted line).

[0032] FIG. 6 is a plan view (side view) illustrating at least a portion of a battery cell heating device according to an embodiment of the present application.

[0033] FIG. 7 is a plan view (viewed from top to bottom) showing at least a portion of a battery cell heating device according to an embodiment of the present application.

[0034] FIGS. 8 to 10 are plan views (side views) showing at least a portion of a battery cell heating device using a spacer, which is a comparative example of the present application.

[0035] Fig. 11 is a plan view showing at least a portion of a battery cell heating device using a spacer, which is a comparative example of the present application (viewed from top to bottom).

[0036] Fig. 12 is a graph showing the curing rate according to the process time of a curable electrolyte composition in a battery cell heating device according to an example and a comparative example of the present application.

[0037] Figure 13 shows a temperature measurement part (P) of a battery cell heating device according to an embodiment and a comparative example of the present application. T ) is a graph showing the temperature according to the process time.

[0038] Before proceeding with a detailed description of this application, 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 this application and may not represent the entire technical spirit of this application. Therefore, various equivalents and variations may exist at the time of filing of this application.

[0039] 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.

[0040] 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.

[0041] 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.

[0042] 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.

[0043] In this specification, the term "battery" may be used with the same meaning as "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.

[0044] The present application can provide a battery cell heating device (10) that can prevent chain reactions that occur due to uneven curing of a curable electrolyte composition (240), resulting in deformation of the shape of a battery cell (200) and cracks, and consequently, performance degradation of the battery. In addition, the present application can provide a battery cell heating device (10) that can shorten the time required for a curable electrolyte composition (240) to sufficiently cure and increase the process speed, thereby improving productivity.

[0045] FIGS. 1 to 3 and 6 are plan views (side view) illustrating at least a portion of a battery cell heating device (10) according to an embodiment of the present application. FIG. 4 is a plan view (side view) illustrating at least a portion of a battery cell heating device (10) according to another embodiment of the present application. FIG. 5 is a cross-sectional view (side view) illustrating at least a portion of a battery cell heating device (10) according to another embodiment of the present application. FIG. 4 and FIG. 5 show a cross-sectional view (side view) illustrating at least a portion of a battery cell heating device (10) according to another embodiment of the present application. In FIGS. 4 and 5, the electrode assembly (230) is built into the body (210), which is indicated by a dotted line. FIG. 7 is a plan view (top view) illustrating at least a portion of a battery cell heating device (10) according to an embodiment of the present application.

[0046] The battery cell heating device (10) can heat the battery cell (200) and may include a heat source for heating. The heat source may be provided in a jig plate (100) to be described later.

[0047] A battery cell heating device (10) can heat a 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 can be referred to as heating. The predetermined temperature can be determined by the configuration of the battery cell (200).

[0048] The battery cell (200) may include a main body (210) and an electrode tab (220) extending from a side surface (211) of the main body (210). The electrode tab (220) may include a positive tab (221) and a negative tab (222). The battery cell (200) may be classified according to the direction in which the positive tab (221) and the negative tab (222) face. For example, if the positive tab (221) and the negative tab (222) face in the same direction, the battery cell (200) may be referred to as a unidirectional battery cell (200), and if the positive tab (221) and the negative tab (222) face in opposite directions, the battery cell (200) may be referred to as a bidirectional battery cell (200). The battery cell (200) of the embodiment of FIG. 1 corresponds to a bidirectional battery cell (200).

[0049] The main body (210) serves as an outer material of the battery cell (200) and may include an electrode assembly (230) therein. The electrode assembly (230) includes a cathode and an anode, and may further include a separator if necessary. The anode of the electrode assembly (230) may be electrically connected to a cathode tab (221) that extends and protrudes from a side surface (211) of the main body (210), and the cathode of the electrode assembly (230) may be electrically connected to a cathode tab (222) that extends and protrudes from a side surface (211) of the main body (210).

[0050] The battery cell (200) may be classified into a cylindrical, square, coin-shaped, or pouch-shaped form, depending on the shape of the main body (210) that serves as the outer material. The main body (210) may, but is not particularly limited to, contain aluminum (Al) to ensure rigidity. In addition, the battery cell (200) according to one embodiment of the present application may be pouch-shaped.

[0051] A curable electrolyte composition (240) may be included in the main body (210). The curable electrolyte composition (240) may be liquid at room temperature. The curable electrolyte composition (240) may be cured by heating. Alternatively, the curable electrolyte composition (240) may be cured by at least one of heating and pressurization. The curable electrolyte composition (240) may be gelled and cured by a crosslinking or polymerization reaction under curing conditions. The curing rate is expressed as a percentage of the content ratio (weight ratio) of the cured curable electrolyte composition (240) to the content of the cured curable electrolyte composition (240) before curing, and is not particularly limited, but may be measured based on the ratio of multiple bonds using FT-IR (Fourier-transform infrared spectroscopy) or based on the ratio of changed structures using NMR (Nuclear Magnetic Resonance Spectroscopy). The cured curable electrolyte composition (240) may be referred to as a gelled electrolyte, and the gelled electrolyte may function as an electrolyte that moves at least one of an electron transport material (lithium or sodium) and electrons in the battery cell (200). In addition, the higher the curing rate, the higher the proportion of the gelled electrolyte that functions as an electrolyte, which may be more advantageous in terms of the performance of the battery cell (200).

[0052] A curable electrolyte composition (240) can be injected into a main body (210) in which an electrode assembly (230) is built and all parts except for the injection port are sealed. The injected curable electrolyte composition (240) can be maintained at room temperature for a predetermined period of time (step S1), and then curing can be performed (step S2). The curing step can include steps S1 and S2.

[0053] Step S1 is a step to ensure that the curable electrolyte composition (240) can be sufficiently impregnated into the electrode assembly (230), and it may be desirable to perform the step at room temperature to minimize side reactions within the curable electrolyte composition (240).

[0054] In step S2, the curable electrolyte composition (240) in the main body (210) can be cured through heating or the like. The battery cell heating device (10) can be used in this step S2. Heat generated from the heat source of the battery cell heating device (10) is transferred to the main body (210), and the curable electrolyte composition (240) can be cured through the heat transferred to the main body (210). That is, heating the battery cell (200) in the battery cell heating device (10) may mean heating the curable electrolyte composition (240) included in the battery cell (200). As the curable electrolyte composition (240) is cured through step S2, the interior of the main body (210) can be filled with a gelled electrolyte. Step S2 can be performed by heating the curable electrolyte composition (240) from room temperature to a predetermined temperature and maintaining the predetermined temperature. Here, the predetermined temperature may be a temperature at which the curable electrolyte composition (240) can initiate a crosslinking or polymerization reaction by heat and perform gelation while minimizing side reactions. For example, the predetermined temperature may be approximately 40°C to 80°C or 50°C to 65°C. In addition, the heating rate during the process of increasing the temperature from room temperature to the predetermined temperature is not particularly limited, but may be approximately 1°C / min to 20°C / min or 5°C / min to 10°C / min in order to minimize side reactions of the curable electrolyte composition (240).

[0055] 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.

[0056] The curable electrolyte composition (240) may include an organic solvent and a polymer (e.g., a polymer or oligomer). The curable electrolyte composition (240) may include an organic solvent, an electron transfer agent salt, a polymer, and a crosslinking initiator.

[0057] The organic solvent included in the curable electrolyte composition (240) 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, one or more 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.

[0058] The organic solvent of the curable electrolyte composition (240) 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 (240) may be greater than the volume of the cyclic carbonate solvent, and the volume may be based on 25° C.

[0059] The electron transport material salt included in the curable electrolyte composition (240) 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.

[0060] The polymer (e.g., a polymer or oligomer) included in the curable electrolyte composition (240) may be crosslinkable. The polymer is not particularly limited, but may include one or more of a fluorine-based polymer, a (meta)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.

[0061] 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 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.

[0062] 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).

[0063] The crosslinking initiator included in the curable electrolyte composition (240) may include a thermal initiator such as AIBN (Azobisisobutyronitrile) or a peroxide initiator such as benzoyl peroxide.

[0064] The curable electrolyte composition (240) may include additives as needed.

[0065] The additive may include, for example, a sulfate-based compound to minimize the decomposition of the curable electrolyte composition (240). 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).

[0066] 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.

[0067] 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.

[0068] The additive may include, for example, a carbodiimide compound to minimize the effects of moisture. The carbodiimide compound may include, for example, dicyclohexylmethanediimine (DCC).

[0069] The battery cell heating device (10) may include a jig plate (100) capable of heating and supporting a battery cell (200). The jig plate (100) may be composed of a plurality of parts to more uniformly transfer heat to the battery cell (200) and minimize external deformation. For example, the jig plate (100) may include a first jig plate (110) supporting one side of the main body (210) and a second jig plate (120) supporting the other side of the main body (210). The other side of the main body (210) may mean the opposite side of the main body (210).

[0070] The jig plate (100) may 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, one or more of aluminum (Al) and stainless steel. 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.

[0071] Meanwhile, the main body (210) of the battery cell (200) may include a side surface (211) including a point from which an electrode tab (220) extends, and may further include a main surface (212) forming an internal space so as to accommodate an electrode assembly (230) and a liquid curable electrolyte composition (240). There may be a plurality of main surfaces (212), and one main surface (212) may be one surface of the main body (210) supported by the first jig plate (110), and the other main surface (212) may be the other surface of the main body (210) supported by the second jig plate (120).

[0072] The first jig plate (110) and the second jig plate (120) may each independently include a heat transfer material to more uniformly transfer heat to the battery cell (200) and minimize external deformation.

[0073] At least one of the first jig plate (110) and the second jig plate (120) may surround the side surface (211) of the main body (210). It may be preferable that the first jig plate (110) and the second jig plate (120) simultaneously surround the side surface (211) of the main body (210). Through this, the battery cell heating device (10) can prevent the problem that the curable electrolyte composition (240) is unevenly cured, causing the shape of the battery cell to become distorted and the curable electrolyte composition (240) to leak. In particular, for example, in the case of a pouch-type battery cell (200), a process of resealing a portion of the pouch while removing the gas pocket is included during the manufacturing process. In case of poor resealing, there is a possibility that the curable electrolyte composition (240) may leak, and if it is cured while still leaking, it may change the appearance of the battery cell (200) or cause continuous sealing failure, which may cause gas venting, and after curing, the electrolyte may not be sufficient, which may directly affect the performance of the battery. The battery cell heating device (10) can minimize leakage of the curable electrolyte composition (240) and prevent problems arising therefrom through the jig plate (100) that surrounds the side (211) of the main body (210).

[0074] Meanwhile, there was a problem that the stress was concentrated on the side surface (211) during the curing step of the curable electrolyte composition (240), causing cracks. For example, the method of pressurizing both sides of the battery cell (200) by introducing a spacer (400S) during the curing process (see FIG. 10) caused the curable electrolyte composition (240) to be concentrated on the side surface (211) that was not pressurized, causing stress, which caused cracks to occur on the side surface (211). The battery cell heating device (10) can prevent the problem of cracks occurring by uniformly applying pressure to the entire battery cell (200) through the jig plate (100) that wraps around the side surface (211) of the main body (210) and preventing the curable electrolyte composition (240) from being concentrated.

[0075] In addition, the battery cell heating device (10) can prevent the performance degradation of the battery as a result through the jig plate (100) that surrounds the side (211) of the main body (210), shorten the curing time required for the curable electrolyte composition (240) to have a sufficient degree of curing, and increase the process speed to improve productivity.

[0076] The first jig plate (110) may include a first side wall portion (111) surrounding a first area among the side surfaces (211) of the main body portion (210) and a first main wall portion (112) surrounding one side of the main body portion (210). Here, the one side of the main body portion (210) may be the main surface (212) of one of the main body portions (210) as described above. The first side wall portion (111) and the first main wall portion (112) may be formed integrally.

[0077] The second jig plate (120) may include a second side wall portion (121) that surrounds a second area among the side surfaces (211) of the main body portion (210) and a second main wall portion (122) that surrounds the other surface of the main body portion (210). Here, the other surface of the main body portion (210) may be the other main surface (212) of the main body portion (210) as described above. The second side wall portion (121) and the second main wall portion (122) may be formed integrally.

[0078] The second region of the side surface (211) covered by the second side wall portion (121) may be different from the first region of the side surface (211) covered by the first side wall portion (111). Referring to FIGS. 1 and 3, the upper (+z direction) side surface (211) based on the positive tab (221) and the negative tab (222) may be the first region, and the lower (-z direction) side surface (211) may be the second region. Here, the first side wall portion (111) may cover the first region, the second side wall portion (121) may cover the second region, and the first region and the second region may not overlap each other but may be different from each other.

[0079] The first side wall portion (111) may further surround at least a portion of one surface of the electrode tab (220). In addition, the second side wall portion (121) may further surround at least a portion of the other surface of the electrode tab (220).

[0080] Specifically, the electrode tab (220) wrapped by the first side wall portion (111) may be at least one of a positive electrode tab (221) and a negative electrode tab (222), and the electrode tab (220) wrapped by the second side wall portion (121) may also be at least one of a positive electrode tab (221) and a negative electrode tab (222). Through this, the battery cell heating device (10) can prevent problems such as the shape of the battery cell becoming distorted and cracks occurring due to the uneven curing of the curable electrolyte composition (240), and consequently, can prevent problems such as performance degradation of the battery. In addition, the curing time required for the curable electrolyte composition (240) to have a sufficient degree of curing can be shortened, and the process speed can be increased, thereby improving productivity.

[0081] The first jig plate (110) and the second jig plate (120) can be coupled. Through this, the first jig plate (110) and the second jig plate (120) can be fixed. The coupling means is not particularly limited, but can be fixed by a fixing member (300) to be described later (see FIGS. 6 and 7).

[0082] The first jig plate (110) and the second jig plate (120) can be combined to form a storage space (AS) in which a battery cell (200) is stored (see FIG. 2). The first side wall portion (111) has a step difference from the inner surface of the first main wall portion (112), and the second side wall portion (121) has a step difference from the inner surface of the second main wall portion (122), so that the first jig plate (110) and the second jig plate (120) can form the storage space (AS). In particular, the depths of the two steps are the same, so that each of the first jig plate (110) and the second jig plate (120) can form half of the storage space (AS).

[0083] The shape of the storage space (AS) is configured to correspond to the outer shape of the battery cell (200) to be stored, so that the battery cell heating device (10) can uniformly transfer heat to the battery cell (200). For example, when the side surface (211) on which the electrode tab (220) is provided has a curved appearance as shown in FIG. 4, the storage space (AS) may also include a curved shape corresponding to the shape of the side surface (211). Specifically, the inner boundary where the first side wall portion (111) and the first main wall portion (112) are connected may include a curved surface. In the same spirit, the inner boundary where the second side wall portion (121) and the second main wall portion (122) are connected may also include a curved surface.

[0084] In addition, referring to FIGS. 4 and 5, each inner boundary of the first main wall portion (112) and the second main wall portion (122) forming the storage space (AS) can have a planar shape corresponding to the main surface (212) of the planar shape.

[0085] In addition, referring to FIG. 5, the first side wall portion (111) can surround one side of the electrode tab (220), and the second side wall portion (121) can surround the other side of the electrode tab (220).

[0086] The first jig plate (110) and the second jig plate (120) may have a symmetrical structure, in which case it may be more advantageous to uniformly transfer heat to the battery cell (200).

[0087] The first jig plate (110) and the second jig plate (120) can form a storage space (AS) so as to minimize empty space within the storage space (AS) when the battery cell (200) is stored in the storage space (AS).

[0088] The first side wall portion (111) of the first jig plate (110) and the second side wall portion (121) of the second jig plate (120) can be formed to be in contact with each other. Through this, most of the storage space (AS) can be formed with only the structures of the first jig plate (110) and the second jig plate (120). The first side wall portion (111) and the second side wall portion (121) can be in contact with the entire periphery area of ​​the battery cell (200) except for the area corresponding to the electrode tab (220). As a result, the first side wall portion (111) and the second side wall portion (121) surround most of the periphery of the side surface (211) of the battery cell (200). At this time, the first side wall portion (111) and the second side wall portion (121) that are in contact with each other can also perform the role of directly supporting one of the first jig plate (110) and the second jig plate (120).

[0089] The storage space (AS) can satisfy R of 1% or less, 0.5% or less, or 0.1% or less according to the following equation 1. Through this, the battery cell heating device (10) can prevent the problem of the shape of the battery cell (200) being distorted due to the curable electrolyte composition (240) being unevenly cured. In addition, the battery cell heating device (10) may not apply a separate pressure to the battery cell (200), but by providing the storage space (AS) similar to the shape and size of the battery cell (200), even if the battery cell (200) expands, the expansion force is supported by the jig plate (100), so that the shape of the battery cell (200) can be maintained.

[0090] [Formula 1]

[0091] R = V2 / V1× 100

[0092] In Equation 1, V2 is the volume of the empty space within the storage space (AS) when the battery cell (200) is not stored, and V1 is the volume of the empty space within the storage space (AS) when the battery cell (200) is stored.

[0093] A battery cell heating device (10) can heat a battery cell (200) stored in a storage space (AS). While heating is performed, the battery cell (200) can be fixed on a first jig plate (110) and a second jig plate (120). The heating of the battery cell (200) can be performed while the first jig plate (110) and the second jig plate (120) are coupled. The battery cell (200) stored in the storage space (AS) can be fixed to minimize movement, and thus can be advantageous in uniformly transmitting heat regardless of the position of the battery cell (200).

[0094] The battery cell heating device (10) may include a fixing member (300) that penetrates the first jig plate (110) and the second jig plate (120) and connects them to each other. The fixing member (300) may be provided in a space other than the storage space (AS) (see FIGS. 6 and 7). The first jig plate (110) and the second jig plate (120) may have a through hole formed in a space other than the storage space (AS) so that the fixing member (300) may penetrate therethrough. A plurality of fixing members (300) may be provided.

[0095] In order to prevent the problem of the curable electrolyte composition (240) being cured in one direction due to gravity, a metal plate that presses both sides of the battery cell (200) during the curing process was applied. However, there was a problem that the curable electrolyte composition (240) was cured unevenly due to excessive pressurization of the metal plate. In order to prevent excessive pressurization of the metal plate, a spacer (400S) that maintains a gap between the metal plates was introduced (see Fig. 10). Although the problem of excessive pressurization of the metal plate was improved through the spacer (400S), it took a lot of time to install the metal plates, including the spacer, to perform the curing process, and there were still problems such as deformation of the outer shape of the battery cell (200).

[0096] The battery cell heating device (10) may not include a spacer that maintains a gap between the first jig plate (110) and the second jig plate (120) in a space other than the storage space (AS). Instead of a spacer, the battery cell heating device (10) prevents problems such as deformation of the shape of the battery cell and cracks caused by uneven curing of the curable electrolyte composition (240) through the side wall portions (111, 121), thereby preventing a problem of deterioration in the performance of the battery, shortening the curing time required for the curable electrolyte composition (240) to have a sufficient degree of curing, and increasing the process speed to improve productivity.

[0097]

[0098] Below, embodiments of the present application are further described with reference to specific examples. The embodiments and comparative examples are intended to exemplify the present application and do not limit the scope of the appended claims. It will be apparent to those skilled in the art that various modifications and variations of the embodiments are possible within the scope and technical spirit of the present application. Furthermore, it is also understood that such modifications and variations fall within the scope of the appended claims.

[0099] <Method of measuring physical properties>

[0100] The physical properties presented in Example 1 and Comparative Example 1 below were measured as follows.

[0101] 1. Installation and dismantling time during the hardening stage

[0102] When manufacturing 50 battery cells (200) in the same manner, the time for installing and dismantling the battery cell heating device (10, 10S) for heating the battery cell (200) into which the curable electrolyte composition (240) was injected during the curing step was measured by adding up the time. The battery cell heating device (10, 10S) was directly installed and dismantled by three researchers.

[0103] 2. Resistance characteristic measurement

[0104] The final battery cell (200) manufactured was charged and discharged with a 2.5 C pulse at every SOC 10 interval from SOC 100 to SOC 0 at SOC 100%, and the resistance was measured using a charge and discharge device, and the first measured resistance (ini.R) was shown.

[0105] 3. Capacity retention evaluation

[0106] The manufactured final battery cell (200) was wrapped around the front and back of the battery cell (200) with an aluminum (Al) plate jig, and the plate jig was fastened with bolts to fix the battery cell (200) so that it does not move. Here, under the condition that 25 ℃ is maintained, it was charged at 0.3 C under constant current / constant voltage (CC / CV) conditions to a voltage (charge voltage) corresponding to SOC98, and then after a 0.05 C cut-off, it was discharged at 0.3 C under constant current (CC) conditions to a voltage (discharge voltage) corresponding to SOC4, and the discharge capacity was measured in this manner, thereby measuring the discharge capacity of 1 cycle and the discharge capacity of 100 cycles. The capacity retention rate was expressed as a percentage of the discharge capacity of 100 cycles divided by the discharge capacity of 1 cycle based on 100 cycles. Here, the unit of the discharge capacity may be Ah.

[0107] 4. Evaluation of reaction area uniformity

[0108] The uniformity area was measured by checking whether there was an air layer inside the gel electrolyte through air scanning of the manufactured final battery cell (200) (the color is displayed differently when measured through air scanning, allowing for distinction).

[0109] 5. Stiffness evaluation

[0110] The stiffness of the final battery cell (200) manufactured was measured using a Universal Testing Machine (UTM) with a stiffness jig attached. The diameters of the upper and lower plates of the jig were both approximately 5 mm, and the span size of the lower jig was approximately 16 times the thickness of the battery cell (200). Afterwards, a three-point bending fracture test was performed, and the load applied to the battery cell (200) was approximately 30 gf, the bending speed was approximately 5 mm / min, and the compression length was at most 2 mm.

[0111] 6. Battery cell appearance evaluation

[0112] The final battery cell (200) manufactured was visually checked for deformation (bending, etc.) in its appearance, and if deformation was present, it was evaluated as '○', and if there was no deformation, it was evaluated as 'X'.

[0113] 7. Evaluation of curing rate according to process time

[0114] After heating the battery cell (200) before curing, each battery cell (200) was disassembled after 1 hour, 3 hours and 5 hours, and the curable electrolyte composition (240) in the process of curing was 1 H NMR analysis was performed in a known manner. The curable electrolyte composition (240) undergoing curing can be sampled at uniform points (measured as uniformity) obtained through air scanning. 1 In H NMR analysis, tetramethylsilane (TMS) diluted in CDCl3 (deuterochloroform) was used as a reference compound (RC) to express chemical shifts, and the ratio corresponding to the structure after curing was derived from this to measure the curing rate. The results are shown in Fig. 12.

[0115] 8. Evaluation of curing rate according to process time

[0116] During the hardening step, the temperature measurement site (P) at one point on the side (211) T ) was measured in a non-contact manner. The results are shown in Fig. 13.

[0117]

[0118] Example 1.

[0119] A battery cell heating device (10) according to Example 1 may refer to FIGS. 1 to 7. A curable electrolyte composition (240) that is liquid at room temperature was injected into a bidirectional pouch-type battery cell (200) having an electrode assembly (230) built therein and sealed. Here, the curable electrolyte composition (240) was used in which a fluorine-based oligomer was contained in a mixed solvent in which ethylene carbonate (EC) and ethyl methyl carbonate (EMC) were mixed in a volume ratio of about 3:7 at 25°C, and the fluorine-based oligomer was contained in an amount of about 1 wt% to 10 wt% based on the total weight of the curable electrolyte composition (240), and included about 0.7 M LiPF6, about 0.5 M LiFSI, and additives. The additives used included 1,3-propane sultone (PS), ethylene sulfate (ESA), and dicyclohexyl methanediimine (DCC). The battery cell heating device (10) includes a first jig plate (110) including a first side wall portion (111) that surrounds one surface of an electrode tab (220) and a first area among the side surfaces (211) of the main body portion (210) and a first main wall portion (112) that surrounds one surface of the main body portion (210). In addition, the battery cell heating device (10) includes a second jig plate (120) that has a symmetrical structure with the first jig plate (110), and the second jig plate supports the second side wall portion (121) that surrounds the other surface of the electrode tab (220) and a second area among the side surfaces (211) of the main body portion (210) and the other surface of the main body portion (210). A battery cell (200) is positioned between a first jig plate (110) and a second jig plate (120), and when the first jig plate (110) and the second jig plate (120) are moved in the direction in which the battery cell (200) is positioned to support the battery cell (200), the first jig plate (110) and the second jig plate (120) are fixed through a fixing member (300).

[0120] Afterwards, the battery cell heating device (10) performed heating after waiting for a predetermined time at room temperature on the battery cell (200), and the temperature measurement part (P) which is one point on the side (211) T ) reached 60°C (a predetermined temperature) and the temperature was maintained to manufacture a battery cell (200) in which curing was completed. Thereafter, a final battery cell (200) was manufactured through a subsequent activation process including a formation process and an aging process.

[0121] Example 2.

[0122] A battery cell heating device (10) according to Example 2 was manufactured by injecting and sealing the same curable electrolyte composition (240) as Example 1 into a bidirectional pouch-type battery cell (200) having an electrode assembly (230) built therein, except that a carbonate-based oligomer was used instead of a fluorine-based oligomer, and manufacturing the final battery cell (200) in the same manner as in Example 1 described above.

[0123] Comparative Example 1.

[0124] The battery cell heating device (10S) according to Comparative Example 1 can be seen with reference to FIGS. 8 to 11. FIGS. 8 to 10 are plan views (side views) illustrating at least a portion of a battery cell heating device (10S) to which a spacer (400S, spacer) is applied, which is a comparative example of the present application. FIG. 11 is a plan view (top-down views) illustrating at least a portion of a battery cell heating device (10S) to which a spacer is applied, which is a comparative example of the present application.

[0125] The battery cell heating device (10S) includes a first jig plate (110S) that surrounds one side of the main body (210) but does not surround the side surface (211) and one side of the electrode tab (220), and a second jig plate (120S) that surrounds the other side of the main body (210) but does not surround the side surface (211) and one side of the electrode tab (220). A battery cell (200) is positioned between a first jig plate (110S) and a second jig plate (120S), and when the first jig plate (110S) and the second jig plate (120S) are moved in the direction in which the battery cell (200) is positioned to support the battery cell (200), the first jig plate (110) and the second jig plate (120) are fixed through a fixing part (300S), and a spacer (400S) is installed to maintain a gap between the first jig plate (110S) and the second jig plate (120S) while surrounding the fixing part (300S). Here, the battery cell (200) was the same as that prepared in Example 1.

[0126] Afterwards, the battery cell heating device (10S) performed heating after waiting for a predetermined time at room temperature on the battery cell (200), and the temperature measurement part (P) which is one point on the side (211) T ) reached 60°C (a predetermined temperature) and the temperature was maintained to manufacture a battery cell (200) in which curing was completed. Thereafter, a subsequent activation process including a formation process and an aging process was performed to manufacture a final battery cell (200). The subsequent activation process including a formation process and an aging process was performed in the same manner as in Example 1.

[0127]

[0128] The physical properties measured in Example 1, Example 2, and Comparative Example 1 are summarized in Table 1 below. In addition, the physical properties measured in Example 1 and Comparative Example 1 are summarized in FIGS. 12 and 13. FIG. 12 is a graph showing the curing rate according to the process time of the curable electrolyte composition (240) in the battery cell heating device (10, 10S) according to Example 1 and Comparative Example 1. FIG. 13 is a graph showing the temperature measurement portion (P) in the battery cell heating device (10, 10S) according to Example 1 and Comparative Example 1. T ) is a graph showing the temperature according to the process time.

[0129] ClassificationExample 1Example 2Comparative Example 1Time required for installation and disassembly in the curing stageApproximately 30 minutesApproximately 30 minutesApproximately 3 hoursResistance characteristics (in.R)Approximately 2 mΩApproximately 2.1 mΩCapacity retention rateApproximately 99%>95%Approximately 98%Reaction area uniformity97%>95%83%Stiffness110%>105%100%(Ref.)Battery cell appearance evaluationXX○

[0130] Referring to Table 1, it can be seen that the installation and dismantling times of Examples 1 and 2 were significantly shortened compared to Comparative Example 1. In addition, Examples 1 and 2 were shown to be superior to Comparative Example 1 in terms of resistance characteristics, capacity retention rate, reaction area uniformity, rigidity, and battery cell appearance evaluation. Referring to FIG. 12, Example 1 was shown to cure at a faster rate and have a higher final cure rate compared to Comparative Example 1. Referring to FIG. 13, Example 1 was shown to reach a predetermined temperature at a faster rate compared to Comparative Example 1 and to cure at this temperature for a longer period of time, thereby shortening the curing time to reach the final cure rate and improving productivity.

[0131]

[0132] A battery cell heating device (10) according to one embodiment of the present application can be widely applied to green technology fields such as electric vehicles, battery charging stations, and other battery-based solar and wind power generation. Furthermore, a battery cell heating device (10) according to one embodiment of the present application can be applied to eco-friendly electric vehicles or hybrid vehicles, etc., to prevent climate change by suppressing air pollution and greenhouse gas emissions.

[0133] 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.

[0134] [Explanation of symbols]

[0135] 10... Battery cell heating device

[0136] 100... jig plate

[0137] 110... 1st jig plate

[0138] 111... First side wall

[0139] 112... First main wall section

[0140] 120... 2nd jig plate

[0141] 121... Second side wall

[0142] 122... Second main wall section

[0143] 200... battery cells

[0144] 210... main body

[0145] 211... side

[0146] 212... Main page

[0147] 220... Electrode tab

[0148] 221... positive tab

[0149] 222... negative tab

[0150] 300... fixed part

[0151] P T ...temperature measurement area

[0152] 400S... spacer

Claims

1. A battery cell heating device for heating a battery cell including a main body and an electrode tab extending from a side of the main body, It includes a first jig plate supporting one side of the main body and a second jig plate supporting the other side of the main body, A battery cell heating device wherein at least one of the first jig plate and the second jig plate surrounds a side surface of the main body.

2. In paragraph 1, The above battery cell includes an electrode assembly and a curable electrolyte composition within the main body, A battery cell heating device wherein the above curable electrolyte composition is cured by heating.

3. In paragraph 2, A battery cell heating device wherein the curable electrolyte composition comprises an organic solvent and a polymer.

4. In paragraph 3, A battery cell heating device, wherein the organic solvent comprises a cyclic carbonate solvent and a linear carbonate solvent, and the polymer comprises at least one of a fluorine polymer and a carbonate polymer.

5. In paragraph 1, The first jig plate includes a first side wall portion that surrounds a first area of the side of the main body portion and a first main wall portion that surrounds one surface of the main body portion, The second jig plate includes a second side wall portion that surrounds a second area of the side of the main body portion and a second main wall portion that surrounds the other surface of the main body portion, A battery cell heating device wherein the first side wall portion further wraps at least a portion of one surface of the electrode tab, and the second side wall portion further wraps at least a portion of the other surface of the electrode tab.

6. In paragraph 1, The first jig plate and the second jig plate are combined to form a storage space in which a battery cell is stored, A battery cell heating device in which the shape of the above storage space is configured to correspond to the outer shape of the battery cell to be stored.

7. In paragraph 6, A battery cell heating device wherein the first jig plate and the second jig plate have a symmetrical structure.

8. In paragraph 6, The above storage space is a battery cell heating device that satisfies R of 1% or less according to the following formula 1: [Formula 1] R = V2 / V1× 100 In Equation 1, V2 is the volume of empty space within the storage space when no battery cells are stored, and V1 is the volume of empty space within the storage space when the battery cells are stored.

9. In paragraph 6, Heating the battery cells stored in the above storage space, A battery cell heating device in which the battery cell is fixed on the first jig plate and the second jig plate while the heating is performed.

10. In paragraph 6, It further includes a fixing member that penetrates the first jig plate and the second jig plate and connects them to each other, The above-mentioned fixed part is a battery cell heating device provided in a space other than the storage space.

11. In paragraph 1, A battery cell heating device further comprising a fixing member that penetrates the first jig plate and the second jig plate and connects them to each other.

12. In paragraph 1, A battery cell heating device wherein the first jig plate and the second jig plate each independently include a heat transfer material having a thermal conductivity of 10 W / m·K or more.

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