Battery cell pressurization device, battery cell pressurization system, and battery pack including same

Abstract

This battery cell pressurization system may include: a sealed case having an internal chamber and including at least one window allowing visual inspection of the internal chamber; a pouch-type battery cell disposed in the internal chamber of the sealed case; a fluid filling the internal chamber and surrounding the pouch-type battery cell; a fluid inlet and outlet in communication with the internal chamber; a pressurization member configured to adjust the pressure of the fluid in the internal chamber so that the pressure applied by the fluid to the pouch-type battery cell is about 1 MPa to about 10 MPa; a heater configured to heat the fluid in the internal chamber; and a pressure measuring member configured to measure the pressure in the internal chamber. The fluid isotropically pressurizes the pouch-type battery cell during at least one among charging and discharging of the pouch-type battery cell.

Description

Battery cell pressurization device, battery cell pressurization system and battery pack including the same

[0001] Cross-citation with related applications

[0002] This application claims the benefit of priority to U.S. Provisional Application No. 63 / 546,685, filed Oct. 31, 2023, U.S. Provisional Application No. 63 / 547,809, filed Nov. 8, 2023, U.S. Non-Provisional Application No. 18 / 930,823, filed Oct. 29, 2024, U.S. Non-Provisional Application No. 18 / 930,862, filed Oct. 29, 2024, and Korean Patent Application No. 10-2024-0151089, filed Oct. 30, 2024, the entire contents of which are incorporated herein by reference.

[0003]

[0004] Technology field

[0005] The present invention relates to a battery cell pressurizing device, a battery cell pressurizing system, and a battery pack including the same.

[0006] With technological advancements and the rapidly growing demand for portable power sources for portable devices, rechargeable secondary batteries have been widely adopted as the primary energy source for various portable devices. Furthermore, secondary batteries are attracting significant attention as power sources for electric vehicles, hybrid vehicles, plug-in hybrid vehicles, urban air mobility (UAM) vehicles, and similar innovations designed to mitigate air pollution and other climate impacts of conventional gasoline or diesel vehicles.

[0007] Secondary batteries are generally categorized by their shape (e.g., form factor). Examples of battery form factor categories include coin-type batteries, cylindrical batteries, prismatic batteries, and pouch batteries. Pouch batteries, in particular, are characterized by a structure combining a metal layer (foil) with an outer pouch made of a multilayer film coated with synthetic resin layers on the upper and lower surfaces of the metal layer. This unique design significantly reduces the weight of pouch batteries compared to cylindrical or prismatic batteries. Furthermore, their flexible form allows them to take on a variety of shapes, making them particularly attractive for a variety of applications.

[0008] The manufacture of pouch-type batteries typically involves a battery cell activation process after battery assembly. This activation process typically involves pressurizing the battery cell using a fixture (e.g., a jig or similar device), then applying current to charge and discharge the battery cell to a predetermined voltage. This activation process is necessary to activate the positive electrode active material during the initial cycle and facilitate the formation of a stable surface film known as the solid electrolyte interface (SEI) layer on the negative electrode.

[0009] For batteries using cathodes with significant volume fluctuations, such as silicon and lithium metal, precise, uniform pressure application during the battery cell pressurization step of the activation process may be necessary to achieve excellent performance. Applying uneven pressure to the battery cell during the activation process not only degrades battery performance but can also have a detrimental effect on its lifespan.

[0010] Therefore, a battery cell pressurization device capable of applying consistent and uniform pressure is required to optimize battery performance.

[0011] [Prior Art Literature]

[0012] [Patent Document]

[0013] Korean Patent Publication No. 10-2019-0072289 (published on June 25, 2019)

[0014] An object of the present invention is to provide a battery cell pressurizing device capable of applying uniform driving pressure to a battery cell and a battery pack including the same.

[0015] Another object of the present invention is to provide a battery cell pressurizing device and a battery pack including the same that can prevent or reduce degradation in performance and lifespan of a battery cell during charging / discharging of the battery cell.

[0016] In one aspect, the present invention provides a battery cell pressurization device comprising: a case having battery cells arranged therein; and a fluid filling the interior of the case and pressurizing the battery cells, wherein the fluid pressurizes the battery cells isotropically during at least one of charging and discharging of the battery cells.

[0017] In another aspect, the present invention provides a battery pack including the battery cell pressurizing device.

[0018] The present invention can provide a battery cell pressurizing device capable of isotropically pressurizing a battery cell and a battery pack including the same.

[0019] In addition, the present invention can provide a battery cell pressurizing device capable of preventing degradation of the performance and lifespan of a battery cell during charging / discharging of the battery cell, and a battery pack including the same.

[0020] FIG. 1 illustrates a perspective view of a battery cell pressurizing device according to one aspect of the present invention.

[0021] FIG. 2 is a diagram illustrating a voltage curve after cycling of a battery cell using a battery cell pressurizing device or a battery cell pressurizing device using a positive pressure jig according to one aspect of the present invention.

[0022] FIG. 3 is a diagram illustrating the coulombic efficiency of a battery cell using a battery cell pressurizing device or a battery cell pressurizing device using a positive pressure jig according to one aspect of the present invention.

[0023] FIG. 4 is a diagram showing the discharge capacity of a battery cell using a battery cell pressurizing device or a battery cell pressurizing device using a positive pressure jig according to one aspect of the present invention.

[0024] FIG. 5 is a cross-sectional view of a battery cell pressurizing device according to another aspect of the present invention.

[0025] FIG. 6 is a diagram showing a weight versus pressure rating chart of a battery cell pressurization device and a comparative example according to aspects of the present invention.

[0026] Figure 7 depicts the force distribution of isotropic pressure applied by a fluid together with a battery cell pressurization device according to aspects of the present invention.

[0027] FIG. 8 is a drawing showing the structure of various uniaxial pouch cell holders (UPCH) compared to the structure of an isotropic pouch cell holder (IPCH) according to aspects of the present invention.

[0028] FIG. 9 is a drawing showing a basic UPCH and an improved UPCH with a spring and rubber gasket according to aspects of the present invention.

[0029] FIG. 10 is a drawing showing an image of pressure paper according to aspects of the present invention.

[0030] FIG. 11 is a diagram showing details of the pressure distribution, the side profile of the cell, the voltage profile, and the reversible discharge capacity of the ASSPC for each pressure paper according to aspects of the present invention.

[0031] FIG. 12 is a drawing showing various comparative schematics of cell stacks according to aspects of the present invention.

[0032] FIG. 13 is a diagram showing a graph showing the cycling pressure characteristics of an ASSPC using IPCH according to aspects of the present invention.

[0033] FIG. 14 is a diagram showing Nyquist plots of pouch cells fabricated at 500 MPa using IPCH according to aspects of the present invention and cycled at 5 MPa, 3 MPa, and 2 MPa.

[0034] FIG. 15 shows graphs of EIS results of ASSPC cycling according to aspects of the present invention, capacity retention and CE of pouch cells, average discharge capacity of pouch cells, and depicts a schematic of the evolution of contact loss between SSE and anode.

[0035] Figure 16 is a schematic diagram showing a pressurizing process according to aspects of the present invention.

[0036] FIG. 17 is a diagram showing an impedance graph of a pouch cell cycled at 5 MPa after 100 cycles according to one aspect of the present invention.

[0037] FIG. 18 is a diagram showing a discharge capacity graph of an ASSPC cycled at 1 MPa, re-pressurized at 500 MPa, and then measured again at 5 MPa according to one aspect of the present invention.

[0038] FIG. 19 is a schematic representation of a double-layer pouch cell according to aspects of the present invention, showing a plasma focused ion beam scanning electron microscope (P-FIB SEM) cross-section, a voltage profile graph of the pouch cell at different cycle numbers, a capacity retention graph of a double-layer ASSPC, and a photograph of a double-layer ASSPC within an IPCH powering an incandescent bulb.

[0039] FIG. 20 is a diagram showing capacity retention and coulombic efficiency graphs of pouch cells manufactured using various pressures according to one aspect of the present invention.

[0040] FIG. 21 is a drawing showing P-FIB cross-sectional images of NCM811 cathode composites calendered at various pressures according to aspects of the present invention.

[0041] Figure 22 is a flow chart of a method of using an isotropic pressurized cell according to aspects of the present invention.

[0042] FIG. 23 is a drawing showing a battery pack according to one aspect of the present invention.

[0043] FIG. 24 is a drawing showing a schematic of an all-solid-state battery according to one aspect of the present invention.

[0044] Hereinafter, aspects of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, all components or portions thereof may be exaggerated for convenience of explanation.

[0045] In addition, it will be apparent to those skilled in the art that the present invention is not limited to the contents described in the attached drawings or this specification, and can be implemented in various forms without departing from the technical spirit of the present invention.

[0046] The shapes, dimensions, areas, ratios, angles, numbers, etc. depicted in the drawings are provided for illustrative purposes only to illustrate various exemplary aspects of the present invention. Therefore, the present invention is not limited to the drawings. Unless otherwise specified, the same reference numbers generally designate the same elements throughout the specification. Furthermore, the term "may" fully encompasses the full meaning and scope of the term "may."

[0047] When terms such as "include," "have," "contain," "consist," "comprise," "made of," or "formed of" are used, one or more other elements may be added, unless a more restrictive term such as "only" is used. The terms and names used herein are used to describe particular aspects only and are not intended to limit the scope of the present invention. An element described in the singular is intended to include the plural, and vice versa, unless the context clearly dictates otherwise.

[0048] When describing elements of the present invention, terms such as "first," "second," "A," "B," "(a)", "(b)", etc. may be used. These terms are intended to distinguish the elements from other elements and are not used to define the nature, basis, order, sequence, or number of the elements.

[0049] The features of the various aspects of the present invention may be partially or wholly combined or combined with one another, and may be operated, connected, or driven together in various ways. The aspects of the present invention may be performed independently of one another or may be performed together in a mutually dependent or related relationship.

[0050] In some cases, battery cells are pressurized using a battery cell pressurization device, including a jig, during the activation process, which involves repeatedly charging and discharging the manufactured battery cells to activate them and remove gases. Furthermore, after manufacturing the battery cells, pressurization during charging / discharging is sometimes required to ensure their usability.

[0051] To pressurize battery cells, a static pressure jig is primarily used. This jig applies pads between the battery cells and regulates pressure using the pack walls (end plates). A static pressure jig is a jig positioned so that the battery cells face each other, and uniaxially pressurizes both or opposite sides of the battery cell in one direction, such as the vertical direction of the battery cell.

[0052] When battery cells are pressurized uniaxially using conventional battery cell pressurization devices, the pressure applied to battery cells containing materials with significant volume changes may not be uniform during charging / discharging. This uneven pressure applied during charging / discharging can lead to reduced battery energy density and lifespan performance.

[0053] Furthermore, when battery cells are pressurized uniaxially using conventional battery cell pressurization devices, uneven pressurization can cause damage such as cracking of the battery cell, decreased cell performance due to increased resistance in certain areas of the cell, and internal short circuits. This can lead to reduced battery cell performance and lifespan.

[0054] To solve or overcome these problems and other limitations of related technologies, the inventors of the present invention have completed a battery cell pressurizing device capable of applying uniform driving pressure to a battery cell using a material with a large volume change, and a battery pack including the same.

[0055] Various aspects of the present invention will now be described in more detail with reference to the drawings. Each battery cell pressurizing device and each component of each battery pack according to all aspects of the present invention are operably coupled and configured.

[0056] FIG. 1 is a perspective view of a battery cell pressurizing device according to one aspect of the present invention.

[0057] Referring to FIG. 1, a battery cell pressurization device (1) according to one aspect of the present invention includes a case (10) in which a battery cell (100) is arranged and a fluid (20) that fills the interior of the case and pressurizes the battery cell (100). In various aspects, the battery cell (100) may be a secondary battery or a solid electrolyte (SSB).

[0058] The battery cell pressurization device (1) according to the present invention can be used when pressurization is required during charging / discharging of a battery cell (100). In aspects of the present invention, the case (10) may also be referred to as a container, chamber, or receptacle.

[0059] According to one aspect, the shape of the case (10) of the battery cell pressurization device (1) is not particularly limited, and may have, for example, a pouch shape, a cylindrical shape, or a square shape. However, aspects of the present invention are not limited thereto. The case (10) may have pressure resistance so as not to be deformed by the pressure of the fluid (20) located inside the case (10). For example, the case (10) may not be deformed at a pressure of several tens of MPa or less, for example, 20 MPa, 15 MPa, or 10 MPa or less. More specifically, the case (10) may be pressurized by the fluid (20) within a pressure range of 1 MPa or more and 10 MPa or less, 2 MPa or more and 9 MPa or less, or 3 MPa or more and 8 MPa or less, and may not be deformed within the pressure range. However, aspects of the present invention are not limited thereto. In addition, the case (10) may have waterproofness or fluid resistance to prevent the fluid (20) from penetrating into the case (10). In this respect, the material forming the case (10) may be, but is not limited to, metals such as aluminum (Al), stainless steel (SUS), titanium (Ti), nickel (Ni), iron (Fe), copper (Cu), or alloys of two or more thereof. For example, the case (10) may be formed of a composite material such as carbon fiber reinforced polymer, glass fiber, or ceramic matrix composite, which can provide a high strength-to-weight ratio and corrosion resistance. In addition, advanced alloys such as Inconel, Hastelloy, or titanium alloys may be used in applications requiring special strength and chemical resistance. However, aspects of the present invention are not limited thereto, and other materials capable of withstanding pressure may also be used.

[0060] According to one aspect, the fluid (20) can pressurize the battery cell (100) when charging / discharging the battery cell (100) with a charge / discharge device. In one aspect of the present invention, the battery cell (100) can be isotropically and uniformly pressurized by using the fluid (20) as a means for pressurizing the battery cell (100). That is, the fluid (20) can isostatically pressurize the battery cell (100).

[0061] The pressure at which the fluid (20) pressurizes the battery cell (100) may be the same as the pressure at which the fluid (20) pressurizes the case. The pressure at which the fluid (20) pressurizes the battery cell (100) may be 1 MPa to 10 MPa. Specifically, the pressure at which the fluid pressurizes the battery cell (100) may be 1 MPa or more, 2 MPa or more, 3 MPa or more, 4 MPa or more, 5 MPa or more, or 10 MPa or less, 9 MPa or less, 8 MPa or less, 7 MPa or less, or 6 MPa or less. If the pressure at which the fluid (20) pressurizes the battery cell (100) is less than 1 MPa, the battery cell (100) may not be sufficiently pressurized, and thus expansion of the battery cell (100) may occur due to gas or internal pressure within the battery cell (100). Additionally, if the pressure at which the fluid (20) pressurizes the battery cell (100) exceeds 10 MPa, physical and chemical damage may occur to the battery cell (100).

[0062] As the fluid (20), a material that is not deformed by the pressure of the fluid itself can be used. In addition, a material that does not affect the performance or lifespan of the battery cell (100) can be used as the fluid (20).

[0063] The fluid (20) may be a gas or a liquid, and specifically, the fluid (20) may be a fire extinguishing agent or a non-flammable or non-volatile gas, an oil, or a gel. In some aspects, the fluid (20) may be a gas such as air, but aspects of the present invention are not limited thereto. For example, the fluid (20) may include an inert gas such as nitrogen, argon, or helium. Additionally, the fluid (20) may include a hydraulic fluid, silicone oil, or a fluorinated compound exhibiting low compressibility and chemical stability, but aspects of the present invention are not limited thereto.

[0064] When the fluid (20) is gas, effective pressurization can be achieved because it has a lower weight and less energy density loss compared to a liquid. Table 1 below shows the results of energy density comparison when air and water are used as the internal fluid (20) of a battery cell pressurization device (1) including battery cells (100). Here, the battery cell pressurization device (1) includes 10 battery cells and is made of aluminum with a thickness of 0.5 mm or includes aluminum.

[0065]

[0066] Battery Cells Pressurized device containing battery cells Internal fluid Air Water Energy (Wh) 13.4134134 Weight (g) 36.3836967 Energy density (Wh / kg) 370160139

[0067]

[0068] As can be seen from Table 1 above, when air was included as the internal fluid of the battery cell pressurization device (1), it was confirmed that the weight was lower and the energy density was higher.

[0069] A battery cell pressurizing device (1) according to one aspect of the present invention may further include a fluid inlet (30) through which a fluid (20) is introduced or discharged.

[0070] For example, when the battery cell (100) is charged, the volume of the battery cell (100) may increase, and when the pressure inside the case (10) increases, the fluid inlet (30) may discharge the fluid (20).

[0071] As another example, when the battery cell (100) is discharged, the volume of the battery cell (100) may decrease, and at this time, when the pressure inside the case (10) decreases, the fluid inlet (30) may introduce fluid (20) to replenish the fluid (20) inside the case (10) to maintain the pressure of the fluid (20).

[0072] The fluid inlet (30) according to some aspects may further include a valve for controlling the inflow and outflow of the fluid (20).

[0073] A battery cell pressurizing device (1) according to one aspect of the present invention may further include a pressurizing member (40) for applying or adjusting pressure inside a case (10). The pressurizing member (40) may be used to apply or adjust a driving pressure inside the case (10) in which a battery cell (100) is placed using a fluid (20). In various aspects of the present invention, the driving pressure may refer to pressurizing or adjusting pressure inside the case (10) by the pressurizing member (40).

[0074] For example, the pressurizing member (40) can pressurize the fluid (20) within the case (10) to apply or regulate the pressure within the case (10). The pressurizing member (40) can include a fluid (20) pressurizing means for pressurizing the fluid (20) or increasing or changing the pressure within the case (10). The pressurizing member (40) can be or include a piston or a hydraulic cylinder, but aspects of the present invention are not limited thereto. In various aspects of the present invention, the pressurizing member (40) can change the pressure within the case (10) by changing the volume of the fluid (20) already within the case (10). Thus, after filling the case (10) with a predetermined amount or volume of fluid (20) using the fluid inlet (30), the pressurizing member (40) can apply, regulate, compensate, or drive the pressure within the case (10) using the fluid (20).

[0075] A sealing member (40) may be arranged in the pressurized member (40) to prevent the fluid (20) filling the inside of the case (10) from being discharged outside the case (10).

[0076] A battery cell pressurization device (1) according to one aspect of the present invention may further include a pressure measuring member for measuring the pressure within the case (10). The pressure measuring member may measure a pressure change for controlling the driving pressure of the case (10) during at least one of charging and discharging of the battery cell (100). In various aspects of the present invention, the pressure measuring member may include one or more types of pressure gauges. The pressure measuring member may include various types of pressure measuring devices such as a mechanical pressure gauge, a digital pressure transducer, a piezoresistive sensor, a capacitive pressure sensor, a strain gauge pressure sensor, a fiber optic pressure sensor, or a microelectromechanical systems (MEMS) pressure sensor, but aspects of the present invention are not limited thereto. In some aspects, the pressure measuring member may also incorporate a pressure switch, a differential pressure sensor, or a pressure transmitter to provide accurate and continuous monitoring of the pressure within the case, but aspects of the present invention are not limited thereto.

[0077] A battery cell pressurizing device (1) according to one aspect of the present invention may further include a wire member for inputting and outputting an electric signal of a battery cell (100). The wire member may be connected to a charging / discharging device to apply current to the battery cell (100) and measure voltage, or may be connected to the charging / discharging device to apply voltage to the battery cell (100) and measure current. In some aspects of the present invention, the battery cell pressurizing device (1) may incorporate a wireless charging mechanism that replaces the physical wire member. This wireless charging system may transfer energy (e.g., applied current or voltage) to the battery cell (100) without a direct electrical connection using electromagnetic induction or resonant inductive coupling. The wireless charging mechanism may perform charging and discharging operations while maintaining the sealing integrity of the case (10), for example, including a transmitting coil outside the case (10) and a receiving coil connected to the battery cell (100) inside the case (10), but aspects of the present invention are not limited thereto.

[0078] The case (10) may further include an opening through which a wire member connected to the battery cell (100) passes to input and output an electrical signal of the battery cell (100). The opening may be a plurality of openings through which a plurality of wire members connected to the positive lead and the negative lead pass, respectively.

[0079] A sealing member may be arranged around the opening to prevent the fluid (20) filling the inside of the case (10) from escaping outside the case (10). Possible sealing members include: an O-ring made of a material such as silicone, nitrile rubber or a fluoroelastomer; a gasket made of compressed fiber material, graphite or PTFE; a mechanical seal with a spring-loaded face; a gland packing made of braided fiber or PTFE; a lip seal or a radial shaft seal; a compression fitting with a ferrule; a sealed glass-to-metal seal; an epoxy or silicone sealant; a bellows seal made of metal or elastomer; a stuffing box seal with adjustable compression; a diaphragm seal made of a flexible material; a labyrinth seal for non-contact sealing; a magnetic fluid seal for a rotating shaft; a pressurizable inflatable seal; or a brush seal made of fine metal or polymer fibers. The selection of sealing elements may vary depending on factors such as operating pressure, temperature, chemical compatibility with the fluid, and the required service life. In some cases, a combination of sealing methods may be used to achieve redundancy and enhanced reliability, but aspects of the present invention are not limited thereto.

[0080] In one aspect of the present invention, the charge / discharge device can activate the battery cell (100) by applying a current to the battery cell (100) through a conductive member to charge / discharge the battery cell (100). The charge / discharge device can perform its function using various processes. For example, a method of detecting a defect in the open circuit voltage (OCV) during aging after fully charging the battery cell (100); a method of then fully discharging the battery cell again to measure the discharge capacity; and a method of then charging the battery cell to 50% of its capacity for shipment. For example, the activation process can be performed under current conditions of 0.05C to 1C and voltage conditions of 1.5V to 5.0V, but is not limited thereto. Other processes, including known processes, can also be used. For example, another process can be pulse charging, which applies a short burst of high current to the battery cell followed by a rest period. Additionally, the charge / discharge device may use a constant current-constant voltage (CC-CV) method, in which a constant current is applied until a specific voltage is reached, and then the voltage is held constant while the current decreases.

[0081] The conductive member may serve to connect the battery cell (100) to a charging / discharging device and apply current to the battery cell (100). The conductive member may be a plurality of conductive members, each connected to a positive lead and a negative lead. Any conductive material may be used as the material forming the conductive member. For example, the conductive member may be a conductive wire. However, aspects of the present invention are not limited thereto.

[0082] A battery cell (100) according to one aspect of the present invention may be a pouch-type battery cell. The battery cell (100) pressurized by the battery cell pressurization device (1) may include a positive electrode, a negative electrode, an electrolyte, and a separator. However, aspects of the present invention are not limited thereto. In addition, the battery cell (100) may further include a positive electrode lead and a negative electrode lead connected to the positive electrode and the negative electrode, respectively.

[0083] The battery cell (100) may be a pouch-type battery cell in which a positive electrode, a negative electrode, an electrolyte, and a separator are embedded in a pouch, and a portion of the lead is exposed outside the pouch. The pouch-type battery cell may be manufactured by placing a separator between the positive electrode and the negative electrode; performing interlayer bonding by pressing using a cold isostatic pressing (CIP) or warm isostatic pressing (WIP) method; then attaching the positive electrode lead and the negative electrode lead, and housing and sealing the thus formed electrode assembly in a pouch.

[0084] Meanwhile, at least two of the sizes of the positive electrode, the negative electrode, and the separator of the battery cell (100) may be different from each other. For example, the size of the positive electrode may be smaller than the size of the negative electrode and the size of the separator. Here, the size may mean at least one of the length in the longitudinal direction (L) and the length in the width direction (W). However, aspects of the present invention are not limited thereto.

[0085] A separator may be included when using a liquid electrolyte. If the positive electrode, negative electrode, and solid electrolyte are included in the pouch, the separator may be omitted. In some aspects, the solid electrolyte may perform the functions of both the electrolyte and the separator. Therefore, according to one aspect of the present invention, the battery cell pressurization device (1) may be used not only for batteries using a solid electrolyte, but also for batteries using a liquid electrolyte and requiring high pressurization during charging / discharging (e.g., silicon anode batteries, lithium metal batteries, etc.). However, aspects of the present invention are not limited thereto.

[0086] However, the structure of the battery cell (100) pressurized by the battery cell pressurization device (1) according to one aspect of the present invention and activated by the battery cell charging / discharging device is not limited to the structure of the battery cell (100) illustrated in the drawing.

[0087] According to a battery cell pressurizing device (1) according to one aspect of the present invention, a fluid (20) is injected through a fluid inlet (30) of a case (10) in which a battery cell (100) is placed, and the injected fluid (20) can isotropically and uniformly pressurize the battery cell (100). In this state, the battery cell (100) can be activated by charging / discharging the battery cell (100) in the battery cell pressurizing device (1). Therefore, the battery cell pressurizing device (1) according to the present invention can prevent a deterioration in performance and lifespan of the battery cell (100) during charging / discharging due to the application of isotropic pressurization.

[0088] The present invention can provide a battery pack including a battery cell pressurization device (1) according to some aspects. That is, the case (10) of the battery cell pressurization device (1) itself can be applied as a battery module. Typically, in an activation process, a battery cell (100) is inserted into the battery cell pressurization device (1) to be activated, and then the activated battery cell (100) is taken out from the battery cell pressurization device (1) to be included or formed into a battery module or pack.

[0089] However, according to aspects of the present invention, the case (or pack, container, module, etc.) of the battery cell pressurization device (1) according to the present invention itself can be used as a battery module or pack, thereby achieving excellent economic effects.

[0090] FIG. 2 is a diagram illustrating a voltage curve after a cycle of a battery cell using a battery cell pressurizing device or a battery cell pressurizing device using a constant pressure jig according to one aspect of the present invention. Here, the battery cell pressurizing device according to one aspect of the present invention pressurizes the battery cell through isostatic pressing, while the battery cell pressurizing device using a conventional constant pressure jig pressurizes the battery cell through uniaxial pressing.

[0091] Referring to FIG. 2, it can be seen that a battery cell using a battery cell pressurization device according to one aspect of the present invention has a higher cell voltage at the same specific capacity than a battery cell using a battery cell pressurization device of a constant pressure jig. Since the battery cell using the constant pressure jig has a higher resistance than the battery cell using the battery cell pressurization device according to the present invention and thus the overvoltage of the battery cell is greater, it was confirmed that the cell voltage of the battery cell isotropically pressurized using the battery cell pressurization device according to the present invention is higher.

[0092] FIG. 3 is a diagram illustrating the coulombic efficiency of a battery cell using a battery cell pressurizing device and a battery cell pressurizing device using a static pressure jig according to aspects of the present invention.

[0093] FIG. 4 is a diagram showing the discharge capacity of a battery cell using a battery cell pressurizing device according to one aspect of the present invention and the discharge capacity of a battery cell using a battery cell pressurizing device using a constant pressure jig.

[0094] In FIGS. 3 and 4, a battery cell using a battery cell pressurizing device according to one or more aspects of the present invention is indicated as an example, and a battery cell using a battery cell pressurizing device using a positive pressure jig is indicated as a comparative example.

[0095] Referring to FIGS. 3 and 4, it can be seen that as several cycles progress, the coulombic efficiency of the battery cell using the battery cell pressurization device according to aspects of the present invention and the battery cell using the battery cell pressurization device of the constant pressure jig are similar, but the battery cell using the battery cell pressurization device according to aspects of the present invention has a higher life performance than the battery cell using the battery cell pressurization device of the constant pressure jig.

[0096] FIG. 5 is a cross-sectional view of a battery cell pressurizing device according to another aspect of the present invention.

[0097] Referring to FIG. 5, the battery cell pressurization device may include a container wall (111) (or case, case wall, or side wall) for accommodating a space in which a pouch cell (1100) can be placed, one or more container caps (110) for closing the container wall (111), one or more container clamps (120) for securing the container caps (110) to the container wall (111), a gas valve (300), such as a ball valve, for controlling the inflow and outflow of a medium to provide pressure, and a pressure gauge (410) for measuring or determining the pressure within the container wall (111). To measure or determine various aspects of the pouch cell (1100) within the battery cell pressurization device, a wire (510) may be connected to the pouch cell (1100) by a connector (540). An example of a connector may be a crocodile clip.

[0098] The battery cell pressurization device may be provided with a fit through connector (520) to provide access to a space within the vessel wall (100). In various aspects of the present invention, the fit through connector (520) may be located in the vessel cap (110), but need not be, and the fit through connector (520) may be located in the vessel wall (111). The location of the gas valve (300) may also vary and may be in the vessel cap (110), the vessel wall (111), or integrated with the pressure gauge (410) or the pit through connector (520). A sealant may be used to ensure sealing of the fit through connector (520), as well as the pressure gauge (410), the gas valve (300), or the vessel clamp (120).

[0099] In one aspect of the present invention, the container wall (111) may be cylindrical, but need not be, and other shapes may be used. The container wall (111) may have an annular protrusion at the open end of the container wall (111), and the annular protrusion may be configured to engage with the annular end of the container cap (110). The container cap (110) may include an internal recess in the inner surface of the container cap (110) to accommodate the annular protrusion of the container wall (111) and the annular end of the container cap (110). In one aspect of the present invention, the diameter of the container wall (111) may be 10 cm, and the height of the container wall may be 20 cm, although aspects of the present invention are not limited thereto.

[0100] In various aspects of the present invention, the battery cell pressurization device may be provided with one or more openings. For example, a first opening for a probe wire (510), a second opening for a pressure gauge (410), and a third opening for a pressure valve (or gas valve) (300) may be provided. When three openings are provided, the third opening may be located away from the first and second openings. However, aspects of the present invention are not limited thereto.

[0101] In various aspects of the present invention, the battery cell pressurization device may include at least one window that allows a user to view the interior of the battery cell pressurization device. The at least one window may be located in the container wall (111), although aspects of the present invention are not limited thereto. For example, the at least one window may also be located in the container cap (110). In various aspects of the present invention, the at least one window may comprise one of glass, quartz, and beryllium, although aspects of the present invention are not limited thereto, and other transparent materials may also be used. When two or more windows are provided, the arrangement of the two windows may be aligned such that a probing beam can be used to probe a battery cell positioned along an alignment axis of the two windows. The probing beam may be X-ray or acoustic, although aspects of the present invention are not limited thereto.

[0102] In various aspects of the present invention, the various components of the battery cell pressurization device may include or be formed of one of steel, stainless steel, aluminum, and titanium, although other materials having strength to withstand pressure and cycling pressure may also be used. In addition, the battery cell pressurization device may include a heater for heating a fluid or a pressurized medium when the fluid or pressurized medium applies an isostatic pressure to the all-solid-state battery within the battery cell pressurization device. In various aspects of the present invention, the battery cell pressurization device may be repeatedly subjected to a pressure of 1 MPa to 5 MPa from the pressurized medium at room temperature. The battery cell pressurization device may be referred to as an isostatic pouch cell holder (IPCH). In various aspects of the present invention, the IPCH may be one or more of the battery cell pressurization devices of FIGS. 1 and 5, but aspects of the present invention are not limited thereto.

[0103] FIG. 6 is a diagram showing a weight versus pressure rating chart of a battery cell pressurization device according to a comparative example and aspects of the present invention.

[0104] Referring to Fig. 6, in a battery cell pressurization device, a fluid is used as the pressurizing medium, so that pressure is applied equally to all points in all directions. Therefore, deformation of the container wall and the arrangement of pouch cells do not affect the pressure uniformity. Consequently, the battery cell pressurization device can use thinner walls to reduce module weight. Comparative examples using different metal alloys with pressure ratings ranging from 1 to 10 MPa and the expected required weight of the battery cell pressurization device are presented. Fig. 6(a) shows values ​​for 304 steel. Fig. 6(b) shows values ​​for 7075 Al alloy. Fig. 6(c) shows values ​​for Ti-6Al-4V. However, aspects of the present invention are not limited thereto, and other materials may also be used.

[0105] Figure 7 depicts the force distribution of isotropic pressure applied by a fluid together with a battery cell pressurization device according to aspects of the present invention. Figure 7(a) shows a pressurized paper that can be vacuum-sealed and placed in a pouch bag and pressurized with IPCH, and the pressure distribution is presented. Figure 7(b) shows a uniform pressure distribution applied to a pouch cell (100). This can be explained by Pascal's principle, which states that a pressure change applied to any point in a closed fluid at rest is transmitted without reduction throughout the fluid in all directions. The application of isotropic pressure can be achieved by using a fluid.

[0106] All-solid-state batteries (ASSBs) are considered a potential successor in the energy storage technology field due to their increased safety by replacing the flammable organic liquid electrolyte of conventional lithium-ion batteries with a less flammable solid electrolyte (SSE). However, ASSBs are more sensitive to cycling pressure, as pressure is crucial for maintaining close interfacial contact. Most battery research uses uniaxial cell holders to apply cycling pressure. Uniaxial cell holders have problems: their capacity to accommodate volume changes of electrode materials during cycling is limited, pressure distribution is uneven, and it is difficult to control pressure over long periods due to material fatigue and mechanical design limitations. To address these issues, the inventors designed isostatic pouch cell holders (IPCHs). By using a fluid as the pressure medium, uniform cycling pressure can be achieved and cycling can be precisely controlled. To demonstrate the potential of IPCHs, LiNi 0.8 Co 0.1 Mn 0.1O2(NCM811) | Li6PS5Cl (LPSCl) | Si all-solid-state pouch cells (ASSPC) were fabricated, and rate performance tests and long-term cycling (100 cycles) were performed under 1 to 5 MPa. The electrochemical performance was found to improve with increasing cycling pressure, and 2 MPa may be the minimum required cycling pressure for the NCM811 | Si system. Finally, the double-layer ASSPC with a theoretical capacity of 100 mAh was cycled using IPCH, and the coulombic efficiency of 76.9% and the capacity of 173.6 mAh g in the first cycle were achieved. -1 A discharge capacity of (88.1 mAh) was obtained, and 150 mAh g after 50 cycles -1 The capacity retention was achieved. IPCH has proven promising for pressure studies and potential commercialization of ASSPC.

[0107] All-solid-state batteries (ASSBs) are attracting attention as a next-generation storage technology, and significant efforts are being invested in their development. The use of solid electrolytes (SSEs) to replace the liquid electrolytes of conventional lithium batteries reduces flammability and leakage issues in ASSBs. Furthermore, while high-energy-density anodes, such as pure Si, have been reported to achieve long cycle life in ASSBs, this is challenging in liquid electrolytes due to the persistent formation of a solid-electrolyte interface (SEI) caused by the large volume change of Si. Despite these advantages, ASSBs present numerous engineering challenges stemming from the solid-solid contact at the interface. Unlike liquid electrolytes, SSEs cannot flow and penetrate into the pores of the electrode. Furthermore, volume expansion of the electrode material can potentially lead to interfacial delamination, which reduces interfacial ion transport and deteriorates the electrochemical performance of the SSE. Therefore, pressure becomes a critical factor in ensuring ASSB performance.

[0108] FIG. 8 is a diagram showing the structure of various uniaxial pouch cell holders (UPCHs) compared to the structure of an isotropic pouch cell holder (IPCH) according to aspects of the present invention. In FIG. 8, (a) shows a UPCH having a plunger cell fixed to the cell holder, (b) shows a multilayer pouch cell, (c) shows a basic UPCH having a simple metal plate, (d) shows a UPCH having a spring and a rubber gasket, and (e) shows an IPCH.

[0109] Pellet-type ASSBs are commonly used in electrochemical testing in laboratories. As illustrated in Figure 8(a), a polymer die and a pair of metal plungers can be used to pelletize the material, including applying manufacturing pressure. During electrochemical testing, a cell holder consisting of bolts, nuts, and plates is required to apply cycling pressure, and the metal plungers serve as current collectors. Because most inorganic SSEs are brittle, the SSE layer typically has a high thickness of 500 μm to ensure sufficient strength to mechanically support the cell. This reduces the energy density of the ASSB, as the SSE layer does not store energy.

[0110] Moreover, friction against the die wall during uniaxial compression makes it difficult to achieve a uniform density distribution across the entire pellet, which can negatively impact their electrochemical performance. Pouch cells with thinner layer thicknesses, larger electrode areas, and no need for a polymer die not only exhibit significantly higher energy densities but also achieve better density distribution after calendering.

[0111] Also, Fig. 8(b) is a drawing showing such a multilayer pouch cell. Since the packaging material of the pouch cell is flexible, isotropic pressure can be applied to further improve the density uniformity. The pouch cell may contain various types of binders, such as polymer binders or all-solid binders. Some all-solid binders, those claimed to be all-solid, contain excessive amounts of polymer binder, lithium salts, and even solvents to compensate for performance issues resulting from not fully achieving all-solid binder, and such partial polymer binder may invalidate the safety function of the ASSB. Nevertheless, several all-solid pouch cells (ASSPCs) using only inorganic SSEs with only a small amount of binder can be used in various multilayer pouch cells (see Table 2).

[0112]

[0113] ASSPC format and cycling conditions Anode | SSE | Cathode Temperature (℃) Manufacturing pressure (MPa) Cycling pressure (MPa) Cycle surface capacity (mAh cm -2 )C speed dimension (cm) 2 )LiNi 0.8 Co 0.15 Al 0.05 O2| Li2SeP2S5| Graphite25--1004.20.1 C8.8x5.3LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2| 75 Li2S·25 P2S5| Graphite30330MPa-101.536C / 242x2LiNi 0.6 Co 0.2 Mn 0.2 O2| Li6PS5Cl | Graphite30492 MPa--4.20.025 C8x6LiNi 0.8 Co 0.1 Mn 0.1 O2| Li6PS5Cl | C-Ag60490 MPa210006.80.5 C11.2x6.7LiNi 09 Co 0.05 Mn 0.05O2| Li6PS5Cl | PVD-Si25300 MPa205030.05 C2.5x2.5S | Li6PS5Cl | Li30300 MPa-1030.01 C3x3LiNi 0.8 Co 0.1 Mn 0.1 O2| Li6PS5Cl | LiIn25--200-0.15 C6x6Sulfur | Solid electrolytes | LiIn30500 MPa-503.20.05 - 2 C-LiNi 0.6 Co 0.2 Mn 0.2 O2| Li6PS5Cl | LiIn---10040.1 C-

[0114]

[0115] Most pouch cells are 3 mAh cm -2 They can have areal capacities of more than 1000 kJ / min, which is comparable to or greater than those of many commercial lithium batteries. However, many commercial pouch cells can have C-rates of less than 0.1 C, and higher temperatures may be required to achieve higher C-rates and areal capacities. Because SSEs do not flow like liquid electrolytes and do not conform to the shape of the electrode materials, pressure must be applied to the ASSB during both fabrication and cycling to ensure close interfacial contact. Many ASSBs are typically fabricated under fabrication pressures of 300 to 500 MPa, and cycling pressure is not mentioned. However, cycling pressure may be a more important indicator, as high cycling pressures will significantly increase the weight of the cell holder and compromise module energy density. Low cycling pressures typically reduce interfacial contact and therefore deteriorate the electrochemical performance of the ASSB, so it is important to prepare a cell holder that provides a uniform cycling pressure.

[0116] Referring to Fig. 8(c), a pouch cell holder composed of bolts, nuts, and rigid plates can be used to apply uniaxial pressure to the pouch cell. Some may attach bearings between the moving plates and bolts to ensure smooth movement and parallelism. However, when applying uniaxial pressure, the cycling pressure of the ASSB may change during cell cycling due to volume changes of the electrode materials. For example, Si can undergo volume expansion of up to 400%, and the thickness of the lithium metal anode can vary for each mAh cm. -2 increases by 5 μm when plated. This can negatively affect their electrochemical performance, especially when pressure-sensitive materials such as lithium metal are used. To address this immediate issue, a spring can be integrated into the cell holder to accommodate the cycling volume change, as shown in Fig. 8(d). Such a design is applicable to, for example, LiNi 0.8 Co 0.1 Mn 0.1The cycling volume change of an O2(NCM811) | Li cell can be successfully reduced from 2 MPa to less than 0.5 MPa, doubling the critical current density. However, aspects of the present invention are not limited thereto. However, rubber and springs can be susceptible to material fatigue and may experience a decrease in applied force over time. As ambient temperature fluctuates, cell pressure can also vary due to the different coefficients of thermal expansion of the pouch cell and bolt. Therefore, a pressure control system is required to ensure the stability of cell cycling. Unfortunately, precisely controlling pressure by turning the bolt is difficult because the motor must overcome significant friction under high pressure loads, and additional effort is required to synchronize the torque of all bolts in a single cell holder. To address this issue, fluids, including gases and liquids, can be used as pressurized media to apply isotropic cycling pressure. Gases can be used when light weight, low cost, or low X-ray absorption (e.g., in situ cell characterization applications) are required, while liquids can be used when pressure loads and heat dissipation are required. Referring to Fig. 8(e), the isotropic pouch cell holder (IPCH) may use chambers and gaskets to contain the pressurized fluid and ASSPC, in contrast to the bolts and nuts of the UPHC. However, aspects of the present invention are not limited thereto.

[0117] Referring to Fig. 8(e), a valve for filling or discharging fluid can be installed, and a wire fit-through can be implemented to electrically connect the ASSPC inside the chamber. Since fluids, especially gases, are significantly more compressible than solids, the IPCH can easily accommodate cell volume changes during cycling. Furthermore, by using a pressure control system for pressurized fluid and gas, a constant cycling pressure can be maintained and achieved in the IPCH for an extended period of time, even in environments with large temperature fluctuations.

[0118] Referring to Fig. 9, a basic UPCH (bear UPCH) with only bolts and nuts and an improved UPCH with springs and rubber gaskets are illustrated. Specifically, Fig. 9 (a) illustrates the basic UPCH with only bolts and nuts, and Fig. 9 (b) illustrates the improved UPCH with springs and rubber gaskets. To observe the pressure distribution, pressure paper can be attached to each cell holder.

[0119] Referring to FIG. 10, images reflecting the pressure distribution applied by various UPCHs and IPCHs according to aspects of the present invention are displayed. Specifically, FIG. 10(a) shows the pressure distribution by a basic UPCH having a metal surface according to FIG. 9(a), FIG. 10(b) shows the pressure distribution by an improved UPCH having a rubber gasket and a spring according to FIG. 9(b), and FIG. 10(c) is a drawing showing the pressure distribution by an IPCH according to FIG. 8(e). When pressure exceeding a threshold value is applied, the pressure paper may change color, for example, may change to red.

[0120] Additional details of the pressure distribution for each pressure paper can be seen in Figs. 11(a), (c) and (e), which correspond to Fig. 10(a), (b) and (c), respectively.

[0121] When tightening the basic UPCH, the parallelism of the metal plates can always be ensured by sequentially tightening the four nuts using a torque wrench and gradually increasing the torque value to the target value at each rotation. However, as shown in Fig. 11(a), an uneven pressure distribution can be obtained for the basic UPCH. This is because when applying uniaxial pressure using a solid surface (e.g., the basic metal), non-contact areas (e.g., the edge of the ASSPC or the concave area due to the imperfect surface flatness of the metal plate) are subjected to lower or no pressure, as shown in Fig. 11(b).

[0122] This problem with the basic UPCH can be somewhat alleviated with the improved UPCH, as the rubber gasket can conform to the shape of the metal plate and the ASSPC. Nevertheless, as shown in Fig. 11(c), a uniform pressure distribution is still not observed. This is because the rubber gasket deformation is lower in areas with larger gaps, resulting in lower pressure in those areas, as shown in Fig. 11(d).

[0123] Meanwhile, IPCH improves the uniformity of cycling pressure. One aspect of IPCH is shown in Fig. 5.

[0124] Referring to Fig. 5, air can be selected as the pressurized medium due to its availability and low cost. The pressure distribution of the pressurized paper vacuum-sealed in a pouch bag and pressurized within the IPCH is shown in Fig. 11(e), which shows a uniform pressure distribution, as shown in Fig. 11(f), which is a result of Pascal's principle. Pascal's principle states that a pressure change applied at any point in a closed fluid at rest is transmitted throughout the fluid in all directions without reduction.

[0125] In addition, Fig. 11(g) shows the voltage profile of the second cycle, and Fig. 11(h) is a diagram showing the reversible discharge capacity of the ASSPC subjected to uniaxial and isotropic pressures, which has an anode size of 3.5 x 1.5 cm. 2 and the area capacity is 4 mAh cm -2 For NCM811 | Li6PS5Cl (LPSCl) | Si ASSPC, calendered at 500 MPa, pressurized in three pouch cell holders, and cycled at 5 MPa at room temperature.

[0126] The cycling pressure of the UPCH can be measured by the torque values ​​of the bolts and nuts, and the cycling pressure of the IPCH can be measured by observing the pressure gauge. Referring to Fig. 11(g), in the voltage profile of the second cycle, when uniaxial pressure is applied to the rigid metal surface (basic ICPH), it can be seen that the cell pressurized with the basic ICPH performs worse during charging, possibly due to worse pressure uniformity, whereas the cells pressurized with the improved UCPH and ICPH can successfully reach 100 cycles. Since the IPCH provides better pressure uniformity and does not suffer from material fatigue that can lead to cycling pressure drop over time, the IPCH may provide a higher discharge capacity to the cell over 100 cycles and may have less capacity loss than the improved UPCH.

[0127] FIG. 12 is a diagram showing various comparative schematics of cell stacks according to aspects of the present invention. In particular, (a) of FIG. 12 shows a cell stack according to one aspect of the present invention, (b) of FIG. 12 shows a cell stack arranged in a cylindrical UPCH, (c) of FIG. 12 shows warpage of a UPCH plate when the thickness is insufficient, and (d) of FIG. 12 shows a cell stack in an IPCH. The dimensions of the cell stack are 20 x 10 x 10 cm. 3In various aspects of the present invention, IPCH can have higher energy density than UPCH at the module level. There are two physical limitations that IPCH can avoid compared to UPCH. First, the number of cells in a cell stack of UPCH can be greater than that of IPCH, and since IPCH does not use a press plate, bending of the press plate can be avoided in UPCH. In addition, in various aspects of the present invention, the configuration of one or more cell stacks can be one of single cell lamination in which individual sheets are sequentially stacked, Z-lamination in which one sheet is continuously placed between other sheets, cylindrical winding of sheets, and angular winding, but aspects of the present invention are not limited thereto.

[0128] Referring to Figure 12 (b), when using UPCH, pressure must be transmitted through other ASSPCs. Therefore, all ASSPCs, including all layers within the pouch, must be perfectly aligned, a task that becomes increasingly difficult as the number of cells within a single stack increases. Referring to Figure 12 (c), the pressurized plate must also be thick enough to resist bending, which can result in higher pressure being applied to the edges of the ASSPC and lower pressure being applied to the center.

[0129] On the other hand, since the fluid is used as the pressurized medium in the IPCH, the pressure is applied equally to all points in all directions. Therefore, deformation of the vessel wall and the arrangement of the ASSPC do not affect the pressure uniformity. Consequently, the IPCH can use thinner walls to reduce module weight. The estimated required weights of the UPCH and IPCH using different metal alloys with pressure ratings ranging from 1 to 10 MPa are presented in Figure 6. Specifically, Figure 6 shows the weight-pressure rating diagrams of the UPCH and IPCH, with Figure 6 (a) showing the case of 304 steel, Figure 6 (b) showing the case of 7075 Al alloy, and Figure 6 (c) showing the case of Ti-6Al-4V Ti alloy. This is because these alloys have different densities, yield strengths, and Young's moduli. As can be seen in Figure 6, for each alloy, the IPCH is significantly lighter than the UPCH for the same density, yield strength, and Young's modulus. Therefore, IPCH may offer advantages in energy density compared to, for example, UPCH. However, aspects of the present invention are not limited thereto.

[0130] IPCH often exhibits high tensile strength, but offers a weight advantage over UPCH when using polymers and composites with low Young's modulus. Implementing ASSPC formats with higher energy densities, such as jerry rolls and Z-laminations, offers additional advantages over IPCH due to fewer geometric constraints on isotropic presses.

[0131] Referring to Figure 6, a pressure rating chart for 304 stainless steel, 7075 Al alloy, and Ti-6Al-4V is provided, but aspects of the present invention are not limited thereto. For example, the IPCH can be made more competitive by using lightweight and strong materials such as carbon fiber or glass fiber. However, aspects of the present invention are not limited thereto. Meanwhile, Table 3 summarizes the mechanical properties of 304 stainless steel, 7075 Al alloy, and Ti-6Al-4V.

[0132]

[0133] Output Strength (MPa)Young's Modulus (GPa)Density 304 SS 200 MPa 200 8.00 g / cm 3 7075 Al450 MPa402.81 g / cm 3 Ti-6Al-4V850MPa1104.43 g / cm 3

[0134]

[0135] Referring to Figure 13, the cycling pressure characteristics of the ASSPC using IPCH are provided. The cycling pressure characteristics are provided at a temperature of 30°C to ensure stable cell performance by avoiding fluctuations in ambient temperature.

[0136] In Fig. 13, (a) is a graph showing the reversible discharge capacity of pouch cells with different operating pressures at different current densities, (b) is a diagram showing the capacity retention and coulombic efficiency of pouch cells fabricated at 500 MPa and cycled at 5 MPa, 3 MPa, and 2 MPa, and (c) is a diagram showing the electrochemical impedance spectroscopy (EIS) fitting results of pouch cells measured after the 1st and 100th cycles at 50% state of charge.

[0137] Referring to Fig. 13(a), all ASSPCs were activated at 5 MPa in the first cycle and then reduced to the target cycling pressure. At 0.1 C, the cells cycled at all pressures except 1 MPa had a capacity of 160 mAh g-1 They exhibit similar discharge capacities, with slight differences due to variations in the arrangement of the cathode composites. 2 MPa is the minimum cycling pressure required to maintain good interfacial contact in ASSPC. The effect of cycling pressure becomes apparent after the C-rate increases above 0.3 C. At 1 C, the polarization of the cell increases sharply, reaching 30 mAh g even at a cycling pressure of 5 MPa. -1 Only can be obtained. Nevertheless, the ASSPC cycled at more than 2 MPa recovers most of the discharge capacity when the C-rate is reduced back to 0.1 C. Referring to Fig. 13(b) and (c), long-term cycling can be performed at 0.2 C by selecting three cycling pressures of 5, 3, and 2 MPa. This is because the current is suitable to distinguish the effect of cycling pressure without significantly deteriorating the discharge capacity according to the rate capability. As the cycling pressure decreases, more cycles are needed for the Coulombic efficiency to approach 100%, and the initial discharge capacity is 149.7 mAh g at 5 MPa. -1 135.37 mAh g at 2 MPa -1 The capacity retention after 100 cycles can also deteriorate from 77.8% at 5 MPa to 47.7% at 2 MPa due to loss of interfacial contact. As the electrode material undergoes repeated volume changes, pressure can be applied to maintain physical contact between the SSE and the electrode material, and higher pressures can better support close interfacial contact.

[0138] FIG. 14 is a diagram showing Nyquist plots of pouch cells fabricated at 500 MPa using IPCH according to aspects of the present invention and cycled at 5 MPa, 3 MPa, and 2 MPa.

[0139] Referring to Fig. 14, (a) is an electrochemical impedance spectroscopy (EIS) graph of the pouch cell for the first cycle at 50% state of charge, and (b) is an EIS graph of the pouch cell for the 100th cycle at 50% state of charge. In Fig. 13 (c), the electrochemical impedance spectroscopy (EIS) of the first and 100th cycles of three ASSPCs were fitted (see Tables 4 and 5 below).

[0140] The four components of the SSE, bulk, grain boundary, anode, and cathode, are listed in order of frequency from highest to lowest. The anode and cathode components were combined in the first cycle. All ASSPCs exhibited similar SSE impedance values ​​at different cycling pressures and cycle numbers, indicating that the SSE separator layer is stable during cycling and is insensitive to cycling pressure. The combined impedance of the anode and cathode exhibits a higher impedance in the first cycle. After 100 cycles, the cathode impedance increases significantly due to the large volume change of Si and the formation of a solid-electrolyte interface (SEI). The anode experiences a smaller volume change during cycling and is protected by the Li3BO3 coating, resulting in a more gradual impedance increase. When the cycling pressure is reduced from 5 to 3 and 2 MPa, both the anode and cathode impedances double. Maintaining good interfacial contact at an appropriate cycling pressure is crucial. In various aspects of the present invention, the positive and negative electrodes can undergo volume changes, which can be up to 5% for the NCM811 positive electrode and 1 mAh cm for Li for the negative electrode. -2 It can contain up to 400% of Si per 5 ㎛.

[0141]

[0142] Cycling pressure cycle number Bulk interface Anode Cathode 5 MPa1 st 2.751.42818.27-100 th 3.0220.9712712.0176.093 MPa1st 2.6092.46223.92-100 th 3.6972.39121.06160.12 MPa1 st 2.5753.18223.25-100 th 4.054.1621.5151.4

[0143]

[0144] Referring to Fig. 15, (a) is the EIS result of ASSPC cycled at 5 MPa after 100 cycles, then reduced to 1 MPa, then increased back to 5 MPa, and then recalendered at 500 MPa; (b) is the capacity retention and CE graph of the pouch cell cycled at 5 MPa before and after recalendering; (c) is the average discharge capacity graph of the pouch cell that was rate tested at 1 MPa, recalendered at 500 MPa, and then subjected to another rate test at 5 MPa; and (d) is a schematic depicting the evolution of the contact loss between the SSE and the anode when insufficient pressure is applied and cannot be restored to the original state even when the pressure returns to the initial value, with the outer circles indicating the friction points and the inner circles indicating the gaps. As depicted, much higher pressures are required to restore the contact between the particles.

[0145] Figure 16 is a schematic diagram illustrating the pressurization process of Figure 15 (a). Figure 17 is an impedance graph of a pouch cell cycled at 5 MPa after 100 cycles, where the pressure applied in the IPCH was reduced from 5 to 1 MPa and then increased back to 5 MPa. After measurement, the fabrication pressure of 500 MPa can be applied to the pouch cell again, and EIS can be measured at 5 MPa.

[0146] Therefore, Figures 16 and 17 and Table 5 show the impedance evolution when the ASSPC undergoes 100 cycles, the pressure is reduced from 5 to 1 MPa, then back to 5 MPa, and finally recalendered at 500 MPa.

[0147]

[0148] ASSPC state Pressure Bulk interface Anode Cathode 1st cycle 5 MPa 2.75 1.42 8 18.27 - 100th cycle 5 MPa 3.02 20.97 12 7 12.01 76.094 MPa 3.57 4 1.21 18.93 12 03 MPa 3.96 3 1.46 6 22.55 14 4.42 MPa 4.19 9 1.75 5 24.21 6 0.81 MPa 4.69 9 2.22 13 0.14 17 5.7 Restart 5 MPa 3.75 8 1.32 12 1.86 12 9.55 00 MPa Pressure 5 MPa 2.54 5 1.21 47.66 24 3.39

[0149]

[0150] Figure 18 is a graph of the discharge capacity of an ASSPC cycled at 1 MPa, repressurized at 500 MPa, and then measured again at 5 MPa. Similar rate capabilities can be achieved with an ASSPC cycled at 5 MPa from the beginning.

[0151] Referring to Figure 18, the impedance of all cell components increases gradually as the pressure decreases. While the impedance of the SSE separator layer increases more slowly by a factor of 1.7, the impedance of both the cathode and anode can increase by a factor of 2.5 when the pressure decreases from 5 MPa to 1 MPa. The impedance of the ASSPC may not recover even when the pressure increases back to 5 MPa. To understand this phenomenon, the ASSPC can be recalibrated, and a dramatic decrease in impedance can be found. It may be less than the initial state after 100 cycles, but greater than the first cycle. When the recalibrated ASSPC is cycled again, its discharge capacity is also 116.5 mAh g in the 100th cycle. -1 141.2 mAh g at 101st cycle -1can be partially restored (see (b) in Fig. 15). To further demonstrate the effectiveness of recalendering, an ASSPC that underwent a rate capability test at 1 MPa can be recalendered and cycled again at 5 MPa, and the performance can be almost fully restored to be similar to the ASSPC cycled at 5 MPa from the beginning (see (c) and Fig. 18 in Fig. 15). A schematic illustrating the impedance evolution is shown in (d) using the anode composite as an example. When the applied pressure decreases, both the SSE and the anode particles can undergo elastic deformation and partially expand to the low-pressure state. This creates larger gaps, resulting in worse interfacial contact, and thus increasing the cell impedance. Some gaps may not close even when the original pressure is reapplied, because the friction between the particles must be overcome, which requires a higher pressure (recalendering). Nevertheless, the impedance cannot be fully restored after long cycles because the SEI and the cathode electrolyte interface (CEI) are formed.

[0152] Referring to Figure 19, (a) is a schematic and plasma focused ion beam scanning electron microscope (P-FIB SEM) cross-section showing the double-layer pouch cell configuration, (b) is a voltage profile graph of the pouch cell at different cycle numbers, and (c) is a 3 x 3.5 cm 2 (d) is a capacity retention graph of a double-layer ASSPC, and (e) is a photograph of a double-layer ASSPC within an IPCH powering an incandescent bulb with an input rating of 2.5 V - 300 mA at a cycling isostatic pressure of 5 MPa.

[0153] Referring to Figure 19, the double-layer ASSPC has a total anode area of ​​21 cm 2 and the theoretical capacity per unit area is 5 mAh cm 2, and can be cycled at 30°C, 0.1°C under 5 MPa. The cell can be stacked in the order of Cu - Si - SSE - NCM811 - Al - NCM811 - SSE - Si - Cu. The FIB-SEM cross-sectional image and details of the cell format are shown in Fig. 19(a). The double-layer ASSPC has an initial Coulombic efficiency of 76.9% and a capacity of 173.6 mAh g -1 (88.1 mAh) discharge capacity. After 100 cycles, 145 mAh g as shown in (b) and (c) of Fig. 19. -1 The discharge capacity can be maintained. Figure 19(d) is a diagram showing a sample of the power capability of a double-layer ASSPC by powering an incandescent bulb rated at 2.5 V and 300 mA. When using LED lighting, the forward bias of a small red LED can be 2 V, which may require a current as low as 3 mA in some cases. The double-layer ASSPC can operate at 3 C. The IPCH can accommodate multiple ASSPCs within its chamber and can have various configurations and shapes.

[0154] In ASSB, cycling pressure is required to maintain good interfacial contact, and IPCH can be used to apply isostatic pressure to the ASSPC via a medium such as compressed air. IPCH can provide a much more uniform pressure distribution than UPCH, which uses a rigid metal surface or a flexible rubber gasket. Because the fluid does not experience material fatigue, unlike many solid elastic materials, the cycling pressure of IPCH can be maintained stably for long periods, resulting in better capacity retention for ASSPC over 100 cycles than UPCH.

[0155] Because fluids can be used in IPCH, thinner walls can be used to construct the IPCH, and various ASSPC formats with higher energy densities can be used. An example of an ASSB is the NCM811 | LPSCl | Si ASSPC, which can be cycled at various pressures. The minimum cycling pressure required to maintain sufficient interfacial contact in the cell can be as low as 2 MPa, and the cell can be cycled at 1C and complete 100 cycles at 0.2C. The rate capability and capacity retention of the ASSPC are positively correlated with the cycling pressure. A double-layer ASSPC with a capacity of 100 mAh can be cycled at 0.1C in an IPCH and complete 50 cycles. The cell can be discharged at a rate of 3C (300 mA), but aspects of the present invention are not limited thereto. Isotropic cycling of the cell can provide a uniform and accurate pressurization method for the commercialization of ASSB.

[0156] In various aspects of the present invention, the ASSPCS used is dry-processed LiNi 0.8 Co 0.1 Mn 0.1The O2 (or NCM811) cathode composite, the dry-processed Li6PS5Cl (or LPSCl) SSE membrane, and the slurry-processed Si anode can be used. The NCM811 cathode composite can be processed by mixing NCM811, LPSCl, vapor-grown carbon fiber (VGCF, Sigma-Aldrich), and polytetrafluoroethylene (PTFE) in a mortar and pestle with a weight ratio of 66:31:3:0.1 until a dough is formed. The dough can then be transferred to a hot roller (TMAXCN) set at 60°C to form a film. Shear force can be applied during mixing and rolling to fiberize the PTFE and strengthen the film. A similar procedure can be applied to fabricate the LPSCl SSE membrane, with a weight ratio of LPSCl:PTFE of 99.9:0.1. To prepare μ-Si electrodes, 99.9 wt% μ-Si (Thermofisher) powder and 0.1 wt% PVDF binder can be dispersed in N-methyl-2-pyrrolidone (NMP) solvent using a Thinky mixer to create a slurry. The slurry can be cast onto a 10 μm copper foil collector piece using a doctor blade in an automatic film coater. The electrode can be vacuum-dried at 80°C for several hours to remove the solvent. The dried electrode can then be punched into an appropriate shape for use in the fabrication of ASSPCs.

[0157] Referring to Fig. 20, capacity retention and coulombic efficiency graphs of pouch cells fabricated using 150 MPa (see (a) of Fig. 20), 350 MPa (see (b) of Fig. 20), and 500 MPa (see (c) of Fig. 20) are shown. The segmented FIB cross-sectional images and porosity are shown in (d) to (f) of Fig. 20. In addition, Fig. 20 (g) shows the 1st cycle measurement of EIS, and Fig. 20 (h) is a drawing showing the 30th cycle measurement of EIS.

[0158] Referring to Fig. 21, P-FIB cross-sectional images of NCM811 cathode composites calendered at (a) 150 MPa, (b) 350 MPa, and (c) 500 MPa are shown, which correspond to (d), (e), and (f) of Fig. 20, respectively.

[0159] Referring to FIG. 22, a method of using an isotropic pressurized cell according to aspects of the present invention is provided. Beginning at operation S2210, the cell may be activated once manufactured or formed at operation S2220. Then, at operation S2230, the activated cell may be pressurized during use, for example, during charging and discharging of the cell. The method may end at operation S2240. In various aspects of the present invention, the cell may be activated and / or pressurized using a pouch cell holder, such as a UPCH or IPCH. In a specific example, in at least one of operations S2220 and S2230, the activation and / or pressurization of the cell (including the ASSB) may be performed by an IPCH.

[0160] FIG. 23 is a diagram showing a battery pack (1000) according to one aspect of the present invention. The battery battery pack (1000) can be used with the battery cell pressurization device illustrated in FIG. 1 and / or FIG. 5. For example, the battery battery pack (1000) can include the battery cell pressurization device illustrated in FIG. 1 and / or FIG. 5. Additionally, the battery battery pack (1000) can include two or more battery cells.

[0161] The cell format of the electrochemical characterization cell and double layer cell can be as follows. The cell format is 4 mAh cm -2It can include a cathode composite film with dimensions of 15 mm x 35 mm x 160 ㎛ with an area loading of 18 mm x 40 mm 300 ㎛, a SSE separator with dimensions of 18 mm x 37 mm and a Si cathode with an NP ratio of 1.2. The area of ​​the cathode composite film can be the smallest and can be the capacity-limiting component, and the SSE separator can be the largest to electrically isolate the cathode and anode. To assemble the electrochemical characterization cell, the Cu, Si, LPSCl, NCM811 cathode composite and Al can be stacked from bottom to top and secured with Kapton tape. An Al tab can be welded to an Al current collector as a cathode terminal, and a Ni tab can be welded to a Cu current collector as a cathode terminal, and the width of the two terminals can be 4 mm. The entire stack can then be vacuum sealed to an Al laminate film and calendared using a cold isostatic press.

[0162] ASSPC calendered at 150, 350, and 500 MPa can be cycled and characterized as shown in Figs. 20 and 21. Among these pressures, 500 MPa can be used for calendering the ASSPC for cycling pressure, which can produce good electrochemical performance. After calendering, cycling pressure can be applied. In a double-layer cell, the cathode composite film exhibited a capacity of 5 mAh cm. -2 The SSE separator may have a dimension of 30 mm x 35 mm x 200 ㎛ with an area loading of 35 mm x 40 mm and a thickness of 300 ㎛, and the Si cathode may have a NP ratio of 1.2 and a dimension of 35 mm x 37 mm. The components of the double-layer cell may be stacked in the following order: Cu, Si, LPSCl, NCM811 cathode composite, Al, NCM811 cathode composite, LPSCl, Si, Cu.

[0163] ASSPC calendered at 150, 350, and 500 MPa can be cycled for 100 cycles at ambient temperature, exhibiting variable Coulombic efficiency and capacity retention. Higher capacity retention is achieved with increasing fabrication pressure due to increased interfacial contact. As shown in the P-FIB / SEM cross-sectional images (see Figure 21), porosity decreases with increasing fabrication pressure. Electrochemical spectrometry (EIS) of the first and 30th cycles also shows reduced cell impedance at higher fabrication pressures, which explains the capacity retention results.

[0164] For analysis, a Neware A211-BTS-4S-1U-100mA-124 battery cycler and a Biologic VSP-300 can be used for galvanostatic cycling and EIS measurements. Voltage cutoff values ​​from 2 to 4.3 V can be selected for the NCM811 | Si system. Since Li diffusivity in pure Si improves after lithiation, an activation cycle can be introduced to all protocols. In the activation cycle, the ASSPC can be cycled at 0.05 C for 5 hours, and then the full cycle can be completed at 0.1 C. During the activation cycle, 5 MPa can be applied and then reduced to the target pressure. To obtain accurate cycling, all ASSPCs can be cycled in an oven set at 30 °C to study the effect of cycling pressure, but aspects of the present invention are not limited thereto. Other temperatures may also be within the scope of the present invention, including temperatures as low as 100°C and as high as 300°C. Rate capability tests may be performed by running ASSPC at 0.1, 0.2, 0.3, 0.4, 0.5, 0.7, 1, and 0.1 C under 5 to 1 MPa, with 3 cycles for each C-rate. For long-term cycling, ASSPC may be cycled at 0.2 C, with a constant voltage step applied down to 0.05 C at the end of charge. ASSPC may be run for up to 100 cycles, and EIS may be obtained at 50% state of charge during discharge in the first and 100th cycles. Z-View software may be used to analyze the EIS results. Double-layer ASSPC may be cycled at 0.1 C, with a constant voltage step applied down to 0.05 C at the end of charge.

[0165] Cross-sections of ASSPCs can be obtained using a Helios G4 PFIB UXe DualBeam plasma-focused ion beam / scanning electron microscope (P-FIB / SEM) with a xenon source. After the ASSPCs are calendered, they can be disassembled, and the anode composites can be attached to SEM stubs, which are sealed in an Ar-filled glovebox. The stubs can then be transferred to the P-FIB / SEM with air exposure of less than 30 seconds. Sample milling can be performed at 30 kV with a current of 2.5 μA. Subsequently, the cross-sections can be polished using lower currents (500 and 60 nA). Electron imaging can be performed at 5 kV and 4 nA. To segment the P-FIB / SEM images, they can be imported into the Trainable Weka Segmentation Fiji module to identify NMC811, LPSCl, and pores. Segmentation can rely on machine learning algorithms manually trained by the user as input images. The phase ratio can then be calculated in MATLAB. The image of the pressure paper can also be processed based on a photograph of the pressure paper, and the result can be rescaled in MATLAB using the ratios of red, green, and blue for each pixel in the JPG file.

[0166] Figure 24 is a schematic diagram of an all-solid-state battery (SSB) according to one aspect of the present invention. Various aspects of the all-solid-state battery (SSB) will be discussed below.

[0167]

[0168] Lithium-ion battery overview

[0169] An all-solid-state battery (SSB) can be charged and discharged multiple times to maintain an electrical load. An all-solid-state battery (1101) includes electrodes, such as a positive electrode (1130) and a negative electrode (1120), and an electrolyte (1140) that allows lithium ions to move between the electrodes. Unlike conventional liquid electrolyte batteries, an all-solid-state battery (SSB) does not contain a flowable liquid. Electricity flows between the electrodes when a circuit is formed between the electrodes. During charging of a lithium-ion rechargeable battery, lithium ions are released from the positive electrode and inserted into the active material of the negative electrode. During discharging of a lithium-ion rechargeable battery, lithium ions are released from the negative electrode and inserted into the active material of the positive electrode. Energy is transferred as the lithium ions shuttle between the electrodes.

[0170]

[0171] All-solid-state battery configuration

[0172] The present invention provides an all-solid-state battery (1101) comprising a positive electrode (1130), a negative electrode (1120), and a solid electrolyte layer 1140 disposed between the positive electrode (1130) and the negative electrode (1120). Although listed as examples, the all-solid-state battery (1101) does not require all of these components. For example, in some configurations, the negative electrode (1120) may be omitted, such as in a cathode-less system. Alternatively, according to one aspect of the present invention, the negative electrode (1120) may comprise a negative electrode material having a metal-carbon composite, such as a silver-carbon blend or composite, wherein silver particles are composited between amorphous and / or crystalline carbon particles. While silver is used as an example, other metals may also be used, including tin, silicon, zinc, or combinations thereof, but aspects of the present invention are not limited thereto.

[0173] The all-solid-state battery (1101) may optionally include additional layers or layers. For example, it may include a separator layer, a protective layer, an inhibitor layer, a solid electrolyte interfacial layer, or a combination thereof. For example, a protective layer may be implemented between the electrode and the solid electrolyte layer. This protective layer may include a material such as lithium phosphate, lithium titanate, or lithium lanthanum zirconium oxide (LLZO), which may help prevent unwanted side reactions at the electrode-electrolyte interface. The protective layer may also help improve the overall life and safety of the battery by mitigating dendrite formation, particularly on the cathode side. Some all-solid-state battery configurations may also include a separator layer. While traditional liquid electrolyte batteries often use porous polymer separators, all-solid-state batteries may use a thin ceramic or glass-ceramic layer as the separator. Such a separator layer may provide additional mechanical support to the battery structure while allowing efficient ion transport. Materials such as LLZO, LATP (lithium aluminum titanium phosphate), or LAGP (lithium aluminum germanium phosphate) can be used for this purpose, but aspects of the present invention are not limited thereto. The separator layer can also be designed to have a gradient structure with properties optimized for contact with both the anode and cathode materials, but aspects of the present invention are not limited thereto.

[0174]

[0175] Cell configuration

[0176] FIG. 24 illustrates an all-solid-state battery (1101) comprising a single cell (1001). In other examples, the all-solid-state battery (1101) may comprise multiple cells, for example, at least two cells, at least three cells, or at least four cells. Connecting cells in series increases the voltage of the all-solid-state battery (1101), and connecting them in parallel increases the amp-hour capacity of the all-solid-state battery (1101). In some embodiments, the all-solid-state battery (1101) may be configured with a combination of series and parallel connections to achieve desired voltage and capacity characteristics. For example, multiple cells may be arranged in groups, with the cells within each group connected in parallel to increase capacity, and these groups again connected in series to increase voltage. This configuration, sometimes called a series-parallel arrangement, allows for greater flexibility in battery design and may help optimize performance for specific applications. Additionally, the number and arrangement of cells may be varied to accommodate various form factor requirements. It can be adjusted to meet your needs.

[0177]

[0178] Cell thickness

[0179] The thickness t1 of the cell (1001) may be 100, 150, 200, 250, 300, 400, 500, 1,000 μm, 2,000 μm, or 5,000 μm. In an embodiment, the thickness t1 of the cell (1001) may be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it may be between 100 μm and 5,000 μm or between 100 μm and 1,000 μm, but aspects of the present invention are not limited thereto.

[0180]

[0181] Bipolar Overview

[0182] The positive electrode (1130) is associated with one polarity (e.g., the positive electrode) of the solid-state battery (1101). The positive electrode (1130) serves as a positive electrode during discharge of the solid-state battery (1101). The positive electrode (1130) is suitable for lithium ion diffusion between the current collector (1160) and the solid electrolyte layer (106). The positive electrode (1130) is in electrical communication with the current collector (1160). In an embodiment, the positive electrode (1130) is formed on and in direct contact with the current collector (1160). In other embodiments, other functional layers may be interposed between the positive electrode (1130) and the current collector (1160), but aspects of the present invention are not limited thereto.

[0183]

[0184] Materials for anodes

[0185] The positive electrode (1130) may be capable of reversible intercalation and deintercalation of lithium ions. For example, the positive electrode (1130) may include one or more of a positive electrode active material, a conductive carbon, a solid electrolyte material, a binder, the like, or a combination thereof. Optionally, the positive electrode (1130) may further include additives such as an oxidation stabilizer, a reduction stabilizer, a flame retardant, a heat stabilizer, an antifogging agent, a thickener, the like, or a combination thereof, but aspects of the present invention are not limited thereto. Examples of such additives may include, but are not limited to, butylated hydroxyanisole (BHA) or butylated hydroxytoluene (BHT) as oxidation stabilizers, ascorbic acid or sodium sulfite as reduction stabilizers, aluminum hydroxide or magnesium hydroxide as flame retardants, phenolic compounds or phosphates as heat stabilizers, polyethylene glycol or silica nanoparticles as antifogging agents, and carboxymethyl cellulose (CMC) or xanthan gum as thickeners.

[0186]

[0187] Materials for positive electrode active materials

[0188] The cathode active material is lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), Li[Ni a Co b Mn c M 1 d ]O2(where M 1 is any one element selected from the group consisting of Al, Ga, In or a combination thereof, and 0.3≤a<1.0, 0≤b≤0.5, 0≤с≤0.5, 0≤d≤0.1, and a+b+с+d=1), Li(Li e M 2 f-e-f M 3 f′ )O 2-g A g (Here 0≤e≤0.2, 0.6≤f≤1, 0≤f′≤0.2, 0≤g≤0.2, M 2 contains at least one element selected from the group consisting of Mn and Ni, Co, Fe, Cr, V, Cu, Zn and Ti, and M 3　 is at least one element selected from the group consisting of Al, Mg and B, and A is at least one element selected from the group consisting of P, F, S and N), or a compound of these substituted with one or more transition metals; Li 1+h Mn 2-h Lithium manganese oxide or the like, such as O4 (where 0≤h≤0.33), LiMnO3, LiMn2O3, LiMnO2; lithium copper oxide (Li2CuO2); LiV3O8, V2O 5　 or vanadium oxides such as Cu2V2O7; LiNi 1-i M 4 i O2 (where M 4 =Ni-site type lithium nickel oxide expressed as Co, Mn, Al, Cu, Fe, Mg, B or Ga, and 0.01≤y≤0.3; LiMn 2-j M 5 j O2 (where M 5 ​​​​=Co, Ni, Fe, Cr, Zn, or Ta, and 0.01≤y≤0.1) or Li2Mn3M 6 O8 (where M 6 =Lithium manganese complex oxide represented by Fe, Co, Ni, Cu, or Zn); LiMn2O4 in which Li is partially substituted with an alkaline earth metal ion; disulfide compounds; LiFe3O4, Fe2(MoO4)3; the like; or combinations thereof, but aspects of the present invention are not limited thereto.

[0189] In addition to the positive electrode active materials mentioned above, the positive electrode can contain other types of materials. For example, lithium iron phosphate (LiFePO4) can be used as the positive electrode active material due to its excellent thermal stability and long cycle life. Lithium manganese iron phosphate (LiMn x Fe 1-x Other phosphate-based materials such as lithium cobalt phosphate (PO4) or lithium cobalt phosphate (LiCoPO4) may also be suitable, but aspects of the present invention are not limited thereto.

[0190] The cathode active material may also include layered oxide materials of various compositions. For example, Li(Ni 1-x-y Co x Mn y )O2(NCM) or Li(Ni 1-x-y Co x Al y )O2(NCA), where the ratios of Ni, Co, Mn, and Al can be adjusted to optimize performance characteristics. For example, NCM811 (LiNi 0.8 Co 0.1 Mn 0.1 Higher energy densities can be achieved by using NCM materials with high nickel content, such as O2. In some cases, the cathode active material is LiNi 0.5 Mn 1.5It may include a spinel structure such as O4, which may provide high voltage operation. Alternatively, it may use a material with a taborite structure such as LiFeSO4F or LiVPO4F, which may provide high energy density and excellent thermal stability, but aspects of the present invention are not limited thereto.

[0191] Composite or blended cathode materials combining two or more active materials may also be used. For example, a blend of layered oxides and spinel materials may be used to balance energy density and power capability. In another example, lithium iron phosphate may be blended with one or more of the cathode active materials described above. In some embodiments, the cathode active material may include surface-modified versions of the aforementioned compounds, wherein the surface modification is aimed at improving stability, conductivity, or other performance indicators, but aspects of the present invention are not limited thereto.

[0192] The cathode active material may also include novel materials, such as disordered rock salt structures (e.g., Li3NbO4-based materials) or high-entropy oxides, which can offer a unique combination of high capacity and structural stability. In some cases, the cathode active material may further modify its electrochemical properties by incorporating dopants or substitutional elements, although aspects of the present invention are not limited thereto.

[0193]

[0194] Particle characteristics of positive electrode active materials

[0195] The positive electrode active material may be in particle form. The positive electrode active material may have a particle size of 10 nm, 20 nm, 30 nm, 50 nm, 70 nm, 100 nm, 200 nm, 300 nm, 400 nm, 500 nm, 1,000 nm, 10 μm, 20 μm, 30 μm, 50 μm, 70 μm, 100 μm, 200 μm, 300 μm, 400 μm, 500 μm, or 1,000 μm. In an embodiment, the particle size of the positive electrode active material may be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it may be between 0 nm and 1,000 μm. The gap between the positive electrode active materials of the positive electrode (1130) may be filled with a solid electrolyte material, but aspects of the present invention are not limited thereto.

[0196]

[0197] Positive electrode active material content of the positive electrode

[0198] The amount of positive electrode active material in the all-solid-state battery (1101) affects the charge and discharge capacity of the all-solid-state battery (1101). To produce a high-capacity positive electrode (1130), the positive electrode (1130) may include a high level of positive electrode active material. For example, the positive electrode (1130) includes at least 30, 40, 50, 60, 70, 80, 90, 95, or 98 wt% of the positive electrode active material based on the total weight of the positive electrode (1130). In an embodiment, the positive electrode active material of the positive electrode (1130) may be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it may be between 40 wt% and 98 wt%, but aspects of the present invention are not limited thereto.

[0199]

[0200] Conductive material of the anode

[0201] The conductive material of the positive electrode (1130) is not particularly limited and can be used as long as it is conductive without causing any chemical change in the corresponding all-solid-state battery (1101). For example, the conductive material may include graphite such as natural graphite or artificial graphite; carbon black such as acetylene black, Ketjen black, channel black, furnace black, lamp black or thermal black; conductive fibers such as carbon fibers or metal fibers; carbon nanotubes (CNTs) including both single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs); metal powders such as fluorocarbon, aluminum or nickel powders; conductive whiskers such as zinc oxide or potassium titanate; conductive metal oxides such as titanium oxide; conductive materials such as polyphenylene derivatives; the like; or combinations thereof. Other conductive materials that can be used in the anode (1130) include, but are not limited to, graphene and its derivatives, such as reduced graphene oxide (rGO) or graphene nanoplates. These two-dimensional carbon materials offer high surface area and excellent electrical conductivity. Conductive polymers, such as polyaniline (PANI), polypyrrole (PPy), or poly(3,4-ethylenedioxythiophene) (PEDOT), can also be used to enhance the conductivity of the electrode while potentially improving its mechanical properties. In some cases, hybrid conductive additives combining other materials, such as CNT-graphene composites or metal-coated carbon materials, can be used to synergistically improve the overall conductivity and performance of the anode (1130), but are not limited to these.

[0202]

[0203] Conductive material content of the anode

[0204] The anode (1130) comprises 1, 2, 5, 10, 15, 20, 25, or 30 wt% of the conductive material, based on the total weight of the anode (1130). In an embodiment, the conductive material of the anode (1130) can be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it can be between 1 wt% and 30 wt%, although aspects of the present invention are not limited thereto.

[0205]

[0206] Materials for binders

[0207] The binder may include, but is not limited to, various types of binder polymers such as polyvinylidene fluoride-co-hexafluoropropylene (PVdF-co-HFP), polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate, polyvinyl alcohol, carboxymethyl cellulose (CMC), starch, hydroxypropyl cellulose, regenerated cellulose, polyvinyl pyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, polyacrylate, ethylene-propylene-diene monomer (EPDM), sulfonated EPDM, styrene butadiene rubber (SBR), fluororubber, polyacrylic acid, polymers thereof in which hydrogen atoms are substituted with Li, Na or Ca, various copolymers thereof, the like, or combinations thereof. In addition to the binder materials mentioned above, other types of binder materials may be used to improve the performance and stability of the positive electrode. For example, the environmental friendliness of the electrode manufacturing process can be improved by using water-soluble binders such as sodium alginate, gelatin, or polyacrylamide. These binders can also provide advantages in terms of electrode flexibility and bonding strength. In some cases, conductive binders such as poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) or polyaniline (PANI) can be used to simultaneously improve the mechanical integrity and electrical conductivity of the electrode. Incorporating novel binder systems, such as self-healing polymers or supramolecular assemblies, can improve the long-term stability and cycle life of the battery. Furthermore, composite binders combining multiple polymers or incorporating inorganic nanoparticles can be used to tailor the mechanical, thermal, and electrochemical properties of the electrode. While some embodiments may utilize bio-derived or biodegradable binders, such as cellulose derivatives or chitosan, to reduce the environmental impact of battery production and disposal, aspects of the present invention are not limited thereto.

[0208]

[0209] Binder content of the positive electrode

[0210] The positive electrode (1130) comprises a binder in an amount of 1, 2, 5, 10, 15, 20, 25, or 30 wt%, based on the total weight of the positive electrode (1130). In an embodiment, the binder of the positive electrode (1130) can be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it can be between 1 wt% and 30 wt%, although aspects of the present invention are not limited thereto.

[0211]

[0212] solid electrolyte material

[0213] The solid electrolyte material of the anode (1130) may be individually configured identically to the material of the solid electrolyte layer (106) to be discussed below. The solid electrolyte material of the anode (1130) may be identical to or different from the material of the solid electrolyte layer (106).

[0214]

[0215] Solid electrolyte material content of the positive electrode

[0216] The positive electrode (1130) comprises 1, 2, 5, 10, 15, 20, 25, or 30 wt% of the solid electrolyte material, based on the total weight of the positive electrode (1130). In embodiments, the amount of the solid electrolyte material of the positive electrode (1130) can be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it can be between 1 wt% and 30 wt%, although aspects of the present invention are not limited thereto.

[0217]

[0218] Thickness of the anode

[0219] The thickness t2 of the anode (1130) may be 10, 20, 50, 100, 150, 200, 250, 300, 400, 500, or 1,000 μm. In an embodiment, the thickness t2 of the anode (1130) may be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it may be between 10 μm and 1,000 μm, but aspects of the present invention are not limited thereto.

[0220]

[0221] Porosity of both poles

[0222] The porosity of the positive electrode (1130) can be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18 volume % based on the total volume of the positive electrode (1130). In an embodiment, the porosity of the positive electrode (1130) can be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it can be between 0 volume % and 18 volume %, although aspects of the present invention are not limited thereto.

[0223]

[0224] Lithium ion diffusion in the anode

[0225] The positive pole (1130) is 1 x 10 -14 cm 2 / s, 1 x 10 -13 cm 2 / s, 1 x 10 -12 cm 2 / s, 1 x 10 -11 cm 2 / s, 1 x 10 -10 cm 2 / s, 1 x 10 -9 cm 2 / s, 1 x 10 -8 cm 2 / s, or 1 x 10 -7 cm 2 / s may include a lithium ion diffusivity of the cathode (1130). In an embodiment, the lithium ion diffusivity of the cathode (1130) may be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, 1 x 10 -14 cm 2 / s and 1 x 10 -7 cm 2 / s may be between, but aspects of the present invention are not limited thereto.

[0226]

[0227] current collector of the positive electrode

[0228] The current collector (1160) collects the electrical energy generated by the positive electrode (1130) and supports the positive electrode (1130). The material of the current collector (1160) is not particularly limited as long as it allows adhesion of the positive electrode (1130), has appropriate electrical conductivity, and does not cause significant chemical changes within the voltage range of the corresponding solid-state battery (1101). For example, the current collector (1160) may be made of or include various materials such as, but not limited to, metal, conductive carbon, or conductive ceramic. The metal of the current collector (1160) may include, but is not limited to, one or more selected from aluminum, aluminum alloys, copper, copper alloys, nickel, nickel alloys, titanium, titanium alloys, iron, iron alloys (e.g., steel, stainless steel), silver, silver alloys, gold, platinum, palladium, chromium, molybdenum, tungsten, tantalum, niobium, zirconium, vanadium, manganese, cobalt, indium, tin, lead, bismuth, or combinations thereof.

[0229]

[0230] Shape and size of the positive electrode collector

[0231] The adhesion of the positive electrode (1130) to the current collector (1160) can be increased by forming microscopic surface irregularities on the surface of the current collector (1160). The current collector (1160) can have various shapes, such as a film, a sheet, a foil, a net, a porous body, a foam, a non-woven body, the like, or a combination thereof, but aspects of the present invention are not limited thereto. The current collector (1160) can also be configured in various other geometric shapes to optimize performance and integration with the positive electrode (1130), and can be sized to fit specific form factors, such as pouch-shaped, cylindrical, and / or prismatic form factors. For example, the current collector (1160) can be configured in a mesh or grid structure, which can provide enhanced mechanical support while maintaining a high surface area for electrode adhesion. In some embodiments, the current collector (1160) can be designed in a wrinkled or corrugated pattern, which can increase the contact area with the positive electrode material and improve overall conductivity. The current collector (1160) may also be fabricated as a perforated sheet to allow for better electrolyte penetration and ion transport. In certain instances, the current collector (1160) may be formed into a three-dimensional structure, such as an interconnected mesh or honeycomb configuration, which may promote efficient current collection while enhancing the structural integrity of the electrode assembly, although aspects of the present invention are not limited thereto.

[0232]

[0233] Thickness of the positive electrode collector

[0234] The thickness t3 of the current collector (1160) may be 3, 5, 10, 15, 20, 25, 50, 100, 150, 200, 300, 400, or 500 μm. In an embodiment, the thickness t3 of the current collector (1160) may be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it may be between 5 μm and 500 μm.

[0235]

[0236] Method for manufacturing anode

[0237] The positive electrode (1130) can be obtained by various methods. For example, a slurry can be formed by mixing and stirring a positive electrode active material with a solvent, optionally including a binder, a conductive material, and a dispersant. The slurry can then be applied (e.g., coated) to a current collector (1160), followed by pressing and drying to obtain the positive electrode (1130). However, aspects of the present invention are not limited thereto.

[0238] In addition to the slurry-based method described, the positive electrode (1130) can be manufactured using various other techniques. For example, a dry powder coating process can be used, in which the positive electrode active material, conductive additive, and binder are mixed in a dry state and then applied directly to the current collector (1160) using electrostatic deposition or mechanical compression. This method can reduce environmental impact by eliminating the need for solvents.

[0239] In some cases, the anode (1130) can be fabricated using additive manufacturing techniques, such as 3D printing. This approach allows for precise control over the electrode structure and porosity, potentially improving the electrode's performance and energy density. Depending on the specific material and desired electrode properties, various 3D printing methods can be utilized, including fused deposition modeling (FDM), selective laser sintering (SLS), or direct ink writing (DIW).

[0240] Another method for manufacturing the positive electrode (1130) may be electrospinning. In this process, a solution containing the positive electrode active material, a conductive additive, and a polymer binder is extruded through a nozzle under an electric field to form nanofibers. These fibers can be directly collected on a current collector (1160) to form a highly porous electrode structure with increased surface area.

[0241] In some embodiments, the positive electrode (1130) may be prepared using a tape casting method. This technique involves spreading a slurry of electrode material onto a moving carrier film using a doctor blade, followed by drying and calendering. The resulting electrode tape may then be laminated to a current collector (1160).

[0242] Alternatively, the anode (1130) can be fabricated using a spray coating technique. In this method, a fine mist of electrode slurry is sprayed onto the current collector (1160) using compressed air or ultrasonic atomization. This approach allows for the production of a thin, uniform electrode layer and can be particularly useful for large-scale production.

[0243] In certain cases, the positive electrode (1130) can be manufactured using a freeze casting method. This process involves freezing a slurry of electrode material and then removing the ice through sublimation to create a porous structure. The resulting porous electrode can then be sintered and attached to a current collector (1160).

[0244] In some applications, the positive electrode (1130) can be prepared using a sol-gel process. This method involves forming a colloidal suspension (sol) containing the positive electrode active material and other components, and then converting it into a gel-like network. The gel can be applied to a current collector (1160) and then heat-treated to form the final electrode structure.

[0245]

[0246] Method for applying anode slurry

[0247] Application of the slurry to the positive electrode (1130) may include using a technique selected from the group consisting of slot die coating, gravure coating, spin coating, spray coating, roll coating, curtain coating, extrusion, casting, screen printing, inkjet printing, spray printing, gravure printing, thermal transfer printing, topographic printing methods, intaglio printing, offset printing, the like, and combinations thereof. In some embodiments, the positive electrode (1130) may be fabricated using a dual layer slot die coating (DLD) technique. This method involves simultaneously applying two different layers of electrode materials to the current collector (1160) in a single pass. The DLD process can create a gradient structure within the electrode, which can optimize both electrochemical performance and mechanical properties. Furthermore, this technique allows for the integration of functional interlayers or protective coatings as part of the electrode fabrication process, which can potentially improve overall battery performance and cycle life.

[0248]

[0249] Solvent for cathode slurry

[0250] The solvent for forming the positive electrode (1130) may include water and / or an organic solvent. For example, it may include N-methyl pyrrolidone (NMP), dimethyl formamide (DMF), acetone, dimethyl acetamide, dimethyl sulfoxide (DMSO), isopropyl alcohol, the like, or a combination thereof. The solvent may be used in an amount sufficient to dissolve and disperse the electrode components (e.g., positive electrode active material, binder, and conductive material) taking into account the slurry coating thickness, production yield, the like, or a combination thereof. Additional organic solvents that may be used include ethanol, methanol, propanol, butanol, ethyl acetate, methyl ethyl ketone, tetrahydrofuran, diethyl ether, and toluene. In some aspects of the present invention, the anode (1130) may be prepared using solvent-free methods such as dry powder processing or melt extrusion, which may eliminate the need for liquid solvents and provide environmental and cost advantages, although aspects of the present invention are not limited thereto.

[0251]

[0252] Dispersant for anode slurry

[0253] The dispersant forming the anode (1130) may include an aqueous dispersant and / or an organic dispersant. For example, it may include N-methyl-2-pyrrolidone. Other possible dispersants include, but are not limited to, polyvinylpyrrolidone (PVP), carboxymethyl cellulose (CMC), sodium dodecyl sulfate (SDS), Triton X-100, polyethylene glycol (PEG), polyacrylic acid (PAA), and various surfactants such as polysorbates or poloxamers.

[0254]

[0255] Bipolar drying technology

[0256] The slurry for the positive electrode (1130) can be dried by evaporating the solvent using heat, electron beam (E-beam), gamma rays, or UV (G, H, I-line) irradiation, or the like, or a combination thereof. For example, the slurry can be vacuum dried at room temperature. The drying step removes the solvent by evaporation, but other components remain to form the positive electrode (1130). In addition to the drying techniques mentioned, the positive electrode (1130) can be dried using other methods, such as infrared (IR) drying, microwave drying, or freeze drying. In some embodiments, a combination of drying techniques, such as convection heating followed by vacuum drying, can be used to optimize the drying process and ensure complete solvent removal while maintaining the integrity of the electrode structure, although aspects of the present invention are not limited thereto.

[0257]

[0258] Cathode Overview

[0259] The cathode (1120) is associated with one polarity (e.g., the negative electrode) of the solid-state battery (1101), which is different from the polarity of the positive electrode (1130). The cathode (1120) is configured as the negative electrode during discharge of the solid-state battery (1101). The cathode (1120) is suitable for lithium ion diffusion between the current collector (1110) and the solid electrolyte layer (106). The cathode (1120) is in electrical communication with the current collector (1110). In an embodiment, the cathode (1120) is formed on and in direct contact with the current collector (1110). In some embodiments, the solid-state battery (1101) may utilize a non-cathode system as described above. In such a configuration, the cathode (1120) may be omitted, and lithium metal may be deposited directly on the current collector (1110) during charging. This approach could potentially increase the energy density of the battery by eliminating the need for a separate cathode material, while potentially reducing the overall thickness of the battery structure.

[0260]

[0261] Cathode materials

[0262] The negative electrode (1120) may be capable of reversible insertion and de-insertion of lithium ions. For example, the negative electrode (1120) may include a negative electrode active material, a binder, the like, or a combination thereof. Optionally, the cathode (1120) may further comprise additives such as oxidation stabilizers (e.g., butylated hydroxyanisole, butylated hydroxytoluene, propyl gallate, tert-butylhydroquinone), reduction stabilizers (e.g., ascorbic acid, sodium sulfite, erythorbic acid, sodium metabisulfite), flame retardants (e.g., aluminum hydroxide, magnesium hydroxide, ammonium polyphosphate, melamine cyanurate), heat or light stabilizers (e.g., phenolic compounds, phosphates, sterically hindered amine light stabilizers, UV absorbers such as benzophenones or benzotriazoles), antifogging agents (e.g., polyethylene glycol, silica nanoparticles, glycerol, sorbitol), thickeners (e.g., carboxymethyl cellulose, xanthan gum), the like, or combinations thereof. Additionally, conductive additives such as carbon black, graphene, or carbon nanotubes can be incorporated to enhance electrical conductivity, and binder modifiers such as styrene-butadiene rubber or polyacrylic acid can improve adhesion and mechanical stability. Functional additives such as fluoroethylene carbonate or vinylene carbonate can also be included to promote the formation of a stable solid electrolyte interfacial layer on the negative electrode surface, but aspects of the present invention are not limited thereto.

[0263]

[0264] Materials for negative electrode active materials

[0265] The negative electrode active material may be made of or include various materials such as, but not limited to, alkaline earth metals, alkaline earth metals, Group 3B metals, transition metals, metalloids, alloys thereof, conductive carbon, the like, or combinations thereof. In embodiments, the negative electrode active material may include, but is not limited to, silicon, a silicon alloy, lithium, a lithium alloy, conductive carbon, or combinations thereof. In embodiments, the lithium alloy is made of or includes a lithium alloy comprising silicon, chlorine, or combinations thereof. The negative electrode active material may be a carbon-based material such as artificial graphite, natural graphite, graphitized carbon fiber, amorphous carbon, or the like; a metal compound capable of forming an alloy with lithium, such as Si, Al, Sn, Pb, Zn, Bi, In, Mg, Ga, Cd, a Si alloy, a Sn alloy, an Al alloy, or the like; SiO x (0 <x<2), SnO2, 바나듐 산화물 또는 리튬 바나듐 산화물과 같은 리튬 이온을 도핑 및 탈도핑할 수 있는 금속 산화물; 그리고 Si-C 복합체 또는 Sn-C 복합체와 같은 금속 화합물과 탄소계 재료를 포함하는 복합체를 포함할 수 있다. 리튬 금속 박막을 음극 활물질로 사용할 수 있다. 탄소계 재료는 저결정성 탄소, 고결정성 탄소, 이와 유사한 것, 또는 이들의 조합을 포함할 수 있다. 저결정성 탄소의 대표적인 예는 소프트 카본 또는 하드 카본이고, 고결정성 탄소의 대표적인 예는 비정질, 판상, 플레이크상, 구형 또는 섬유상 천연 흑연 또는 인조 흑연, 키시 흑연, 열분해 탄소, 메조페이스 피치계 탄소 섬유, 메조카본 마이크로비즈, 메조페이스 피치, 석유 또는 콜타르 피치 유래 코크, 이와 유사한 것, 또는 이들의 조합과 같은 고온 소성 탄소이다. 언급된 재료 외에도, 음극 활물질은 리튬 티타네이트(Li4Ti5O 12) or titanium-based compounds such as titanium dioxide (TiO2), which can provide excellent cycling stability and high-rate charge-discharge capability. Other potential materials include molybdenum oxide (MoO x ), iron oxide (FeO x ), or nickel oxide (NiO x ) and transition metal oxides, which can provide high theoretical capacities. In some cases, composite materials combining different active materials, such as silicon-graphite composites or tin-carbon composites, can be used to alleviate the limitations of individual materials while taking advantage of the advantages of multiple materials, but aspects of the present invention are not limited thereto.

[0266]

[0267] Dendrite formation

[0268] When the negative electrode (1120) is made of or includes lithium or a lithium alloy, dendrites may form on the negative electrode (1120). Dendrites are metallic lithium structures that form when excess lithium ions accumulate on the surface of the negative electrode (1120). The formed dendrites may damage the solid electrolyte layer (106), reduce the battery capacity of the all-solid-state battery (1101), and / or lead to undesirable performance of the all-solid-state battery (1101). Dendrite formation is a significant challenge in lithium-based batteries because these structures can grow through the electrolyte, potentially causing short circuits and safety hazards. The growth rate and morphology of dendrites can be affected by factors such as current density, temperature, and the properties of the electrolyte-electrode interface.

[0269]

[0270] Solid electrolytes offer several advantages over liquid electrolytes in mitigating dendrite formation. The mechanical strength of solid electrolytes can help inhibit dendrite growth by providing a physical barrier to lithium metal penetration. Furthermore, the uniform ion distribution of solid electrolytes can promote more uniform lithium deposition, reducing the likelihood of localized dendrite nucleation. Some solid electrolytes can further inhibit dendrite formation by forming a stable interface with the lithium metal anode. However, it is important to note that while solid electrolytes can significantly reduce the risk of dendrite growth, they cannot completely eliminate it. Current research aims to develop advanced solid electrolyte materials with enhanced dendrite inhibition capabilities.

[0271]

[0272] Characteristics of negative active materials

[0273] The negative active material may be in particle form or in a continuous single form (e.g., a thin film or sheet). In embodiments where the negative active material is in particle form, the negative active material may have a particle size of 10 nm, 20 nm, 30 nm, 50 nm, 70 nm, 100 nm, 200 nm, 300 nm, 400 nm, 500 nm, 1,000 nm, 10 μm, 20 μm, 30 μm, 50 μm, 70 μm, 100 μm, 200 μm, 300 μm, 400 μm, 500, or 1,000 μm. In embodiments, the particle size of the negative active material may be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it may be between 10 nm and 1,000 μm, but aspects of the present invention are not limited thereto.

[0274]

[0275] Negative active material content of the negative electrode

[0276] The amount of the negative active material in the all-solid-state battery (1101) affects the charge and discharge capacity of the all-solid-state battery (1101). To produce a high-capacity negative electrode (1120), the negative electrode (1120) may include a high level of the negative active material. For example, the negative electrode (1120) includes at least 70, 80, 90, 95, 98, 99, or 100 wt % of the negative active material based on the total weight of the negative electrode (1120). In an embodiment, the amount of the negative active material in the negative electrode (1120) may be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it may be between 70 wt % and 100 wt %, but aspects of the present invention are not limited thereto.

[0277]

[0278] Material for binder of cathode

[0279] The binder may include various types of binder polymers, such as polyvinylidene fluoride-co-hexafluoropropylene (PVdF-co-HFP), polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate, polyvinyl alcohol, carboxymethyl cellulose (CMC), starch, hydroxypropyl cellulose, regenerated cellulose, polyvinyl pyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, polyacrylate, ethylene-propylene-diene monomer (EPDM), sulfonated EPDM, styrene butadiene rubber (SBR), fluororubber, polyacrylic acid, polymers thereof in which hydrogen atoms are substituted with Li, Na or Ca, various copolymers thereof, the like, or combinations thereof. In addition to the binders mentioned, other suitable binders that can be used in the negative electrode include polyimides, polyamide-imides, polyurethanes, polyethylene oxide (PEO), poly(ethylene-co-vinyl acetate) (PEVA), poly(vinyl acetate) (PVA), alginates, chitosan, guar gum, xanthan gum, carrageenan, pectin, gelatin, lignin, and various water-soluble polymers or derivatives thereof. In some cases, conductive polymers such as polypyrrole, polyaniline, or poly(3,4-ethylenedioxythiophene) (PEDOT) may also be used as binders to simultaneously enhance adhesion and electrical conductivity within the negative electrode, but aspects of the present invention are not limited thereto.

[0280]

[0281] Binder content of the cathode

[0282] The cathode (1120) may comprise 0, 1, 2, 5, 10, 15, 20, 25, or 30 wt% of the binder, based on the total weight of the cathode (1120). In an embodiment, the binder of the cathode (1120) may be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it may be between 0 wt% and 30 wt%, although aspects of the present invention are not limited thereto.

[0283]

[0284] Thickness of the cathode

[0285] The thickness of the cathode (1120) may be 10, 20, 30 50, 60, 70, or 100 μm. In an embodiment, the thickness t4 of the cathode (1120) may be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it may be between 10 μm and 100 μm or between 10 μm and 20 μm, but aspects of the present invention are not limited thereto.

[0286]

[0287] Porosity of the cathode

[0288] The porosity of the cathode (1120) can be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18 volume % based on the total volume of the cathode (1120). In an embodiment, the porosity of the cathode (1120) can be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it can be between 0 volume % and 18 volume %, although aspects of the present invention are not limited thereto.

[0289]

[0290] Lithium ion diffusion rate in the negative electrode

[0291] The cathode (1120) is 1 x 10 -14 cm 2 / s, 1 x 10 -13 cm 2 / s, 1 x 10 -12 cm 2 / s, 1 x 10 -11 cm 2 / s, 1 x 10 -10 cm 2 / s, 1 x 10 -9 cm 2 / s, 1 x 10 -8 cm 2 / s, or 1 x 10-7 cm 2 / s may include a lithium ion diffusivity of the negative electrode (1120). In an embodiment, the lithium ion diffusivity of the negative electrode (1120) may be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, 1 x 10 -14 cm 2 / s and 1 x 10 -7 cm 2 / s may be between, but aspects of the present invention are not limited thereto.

[0292]

[0293] negative current collector

[0294] The current collector (1110) collects the electrical energy generated by the negative electrode (1120) and supports the negative electrode (1120). The material of the current collector (1110) is not particularly limited as long as it allows adhesion of the negative electrode (1120), has appropriate electrical conductivity, and does not cause significant chemical changes in the voltage range of the corresponding all-solid-state battery (1101). For example, the current collector (1110) is made of or includes a metal or conductive carbon, but is not limited thereto. The metal of the current collector (1110) may include, but is not limited to, one or more selected from the group consisting of aluminum, an aluminum alloy, copper, a copper alloy, nickel, a nickel alloy, titanium, a titanium alloy, iron, an iron alloy (e.g., steel, stainless steel), silver, a silver alloy, or a combination thereof.

[0295]

[0296] Shape and size of the negative electrode collector

[0297] The adhesion of the negative electrode (1120) to the current collector (1110) can be increased by forming microscopic surface irregularities on the surface of the current collector (1110). The current collector (1110) can have various shapes such as a film, a sheet, a foil, a net, a porous body, a foam, a non-woven body, the like, or a combination thereof, but aspects of the present invention are not limited thereto. In addition to the shapes mentioned, the current collector (1110) can have a honeycomb structure, a perforated sheet, a woven or non-woven mesh, a sintered porous body, or a three-dimensional interconnected network structure. These various shapes can be adjusted to optimize the surface area, mechanical strength, and current collection efficiency of the current collector (1110). Furthermore, the current collector (1110) can be designed to fit various shapes of all-solid-state batteries, such as pouch-type batteries, cylindrical batteries, or prismatic batteries, each of which offers unique advantages in terms of packaging efficiency, thermal management, and overall battery performance.

[0298]

[0299] Thickness of the negative electrode collector

[0300] The thickness t5 of the current collector (1110) may be 3, 5, 10, 15, 20, 25, 50, 100, 150, 200, 300, 400, or 500 μm. In an embodiment, the thickness t5 of the current collector (1110) may be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it may be between 5 μm and 500 μm, but aspects of the present invention are not limited thereto.

[0301]

[0302] Method for manufacturing cathode

[0303] The negative electrode (1120) can be obtained by various methods, such as atomic deposition, extrusion, rolling, slurry methods, or combinations thereof. For example, a slurry can be formed by mixing and stirring the negative electrode active material with a solvent, optionally including a binder and a dispersant. The slurry can then be applied (e.g., coated) to a current collector (1110), followed by pressing and drying to obtain the negative electrode (1120). In addition to the methods mentioned, the negative electrode (1120) can be manufactured using various other techniques, including a dry electrode process. While these alternative methods may offer advantages in terms of environmental impact, cost-effectiveness, and scalability, aspects of the present invention are not limited thereto.

[0304] As an alternative to the slurry method, dry powder coating can be used. In this process, the negative active material, conductive additive, and binder are mixed in a dry state and then applied directly to the current collector (1110) using electrostatic deposition or mechanical compression. This method eliminates the need for solvents, potentially reducing environmental impact and processing time.

[0305] The cathode (1120) can be fabricated using additive manufacturing techniques such as 3D printing. Various 3D printing methods, including fused deposition modeling (FDM), selective laser sintering (SLS), or direct ink writing (DIW), can be utilized depending on the specific material and desired electrode properties. This approach allows for precise control over the electrode structure and porosity.

[0306] Electrospinning is another potential method for manufacturing the cathode (1120). In this process, a solution containing the cathode active material, a conductive additive, and a polymer binder is extruded through a nozzle under an electric field to form nanofibers. These fibers can be directly collected on a current collector (1110) to form a highly porous electrode structure with increased surface area.

[0307] The cathode (1120) can be prepared using tape casting. This technique involves spreading a slurry of electrode material onto a moving carrier film using a doctor blade, followed by drying and calendering. The resulting electrode tape can then be laminated to a current collector (1110).

[0308] The cathode (1120) can be fabricated using a spray coating technique. A fine mist of electrode slurry is sprayed onto the current collector (1110) using compressed air or ultrasonic atomization. This approach enables the creation of a thin, uniform electrode layer and can be particularly useful for large-scale production.

[0309] Freeze casting is another potential method for manufacturing the cathode (1120). This process involves freezing a slurry of electrode material and then removing the ice through sublimation to create a porous structure. The resulting porous electrode can then be sintered and attached to a current collector (1110).

[0310] In some cases, the negative electrode (1120) may be prepared using a sol-gel process. This method involves forming a colloidal suspension (sol) containing the negative electrode active material and other components, and then converting it into a gel-like network. The gel may be applied to a current collector (1110) and then heat treated to form the final electrode structure.

[0311] In certain applications, thin-film anodes can be formed directly on current collectors (1110) using physical vapor deposition (PVD) or chemical vapor deposition (CVD) techniques. These methods can produce highly uniform and dense electrode layers, which may be particularly useful for certain types of all-solid-state batteries.

[0312] Finally, composite anode materials can be prepared using mechanical alloying and high-energy ball milling, which can then be pressed into an electrode or applied to a current collector (1110) using one of the methods mentioned above. This technique may be particularly useful for producing nanostructured or amorphous anode materials with enhanced electrochemical properties.

[0313]

[0314] Ball milling general

[0315] Ball milling is a useful technique for preparing and mixing all-solid-state battery components. Ball milling is a widely used mechanical technique for grinding powders into fine particles and mixing materials in a variety of applications. In the context of all-solid-state batteries, ball milling is often used to mix and blend electrode materials, solid electrolytes, and other components. Examples of ball milling devices include planetary ball mills, agitated ball mills, and vibrating ball mills. These devices typically consist of a rotating or vibrating chamber containing grinding balls made of materials such as steel, ceramic, or zirconia.

[0316]

[0317] Uniform mixing

[0318] Ball milling is effective in achieving uniform mixing of different powders. This is crucial for uniform distribution of electrode materials and solid electrolyte components, which ultimately affects the overall performance of the battery.

[0319]

[0320] Reduction of particle size

[0321] Ball milling can reduce the particle size of the relevant material, increasing surface area and enhancing reactivity. Smaller particle sizes can improve electrochemical reaction kinetics, contributing to better battery performance.

[0322]

[0323] Improvement of the electrode-electrolyte interface

[0324] Ball milling can promote the formation of a well-defined interface between the electrode and the solid electrolyte. This is crucial for promoting efficient ion transport and minimizing interfacial resistance in all-solid-state batteries.

[0325]

[0326] Acceleration of solid-state reactions

[0327] Ball milling can promote the formation of desired phases and structures in materials by inducing solid-state reactions between different components. This is particularly relevant for the synthesis of composite electrode materials or the preparation of composite electrolyte materials provided herein.

[0328]

[0329] Optimization of conductivity

[0330] Ball milling can be used to optimize the conductivity of electrode materials by ensuring good distribution of conductive additives, such as carbon or metal nanoparticles, within the composite. Alternatively, it can be used to optimize the distribution of additive materials within the solid electrolyte provided herein.

[0331]

[0332] Shape control

[0333] The milling process can also affect the material's morphology, including particle shape and size distribution. Controlling these aspects is crucial for achieving the desired electrochemical properties and overall performance of all-solid-state batteries.

[0334]

[0335] Energy Considerations

[0336] Ball milling is an energy-intensive process, and milling duration and speed must be carefully controlled to avoid unwanted reactions or material damage due to excessive heating.

[0337]

[0338] Method for applying cathode slurry

[0339] Application of the slurry for the negative electrode (1120) may include using a technique selected from the group consisting of slot die coating, gravure coating, spin coating, spray coating, roll coating, curtain coating, extrusion, casting, screen printing, inkjet printing, spray printing, gravure printing, thermal transfer printing, top-plate printing methods, intaglio printing, offset printing, the like, and combinations thereof. In addition to the aforementioned techniques, other methods for applying the negative electrode slurry to the current collector include doctor blade coating, dip coating, and meniscus coating. Dual slot die layer coating may also be used, which allows for the simultaneous application of two different electrode material layers to the current collector in a single pass. This method can create a gradient structure within the electrode, potentially optimizing both electrochemical performance and mechanical properties.

[0340]

[0341] Solvent for cathode slurry

[0342] The solvent for forming the negative electrode (1120) may include water and / or an organic solvent. For example, it may include N-methyl pyrrolidone (NMP), dimethyl formamide (DMF), acetone, dimethyl acetamide, dimethyl sulfoxide (DMSO), isopropyl alcohol, the like, or a combination thereof. The solvent may be used in an amount sufficient to dissolve and disperse the electrode components (e.g., the negative electrode active material and the binder) considering the slurry coating thickness, production yield, the like, or a combination thereof. Additional organic solvents that may be used include ethanol, methanol, propanol, butanol, ethyl acetate, methyl ethyl ketone, tetrahydrofuran, diethyl ether, and toluene. In some embodiments, the negative electrode (1120) may be prepared using a solvent-free method, such as dry powder processing or melt extrusion, which may eliminate the need for liquid solvents and may provide environmental and cost advantages, although aspects of the present invention are not limited thereto.

[0343]

[0344] Dispersant for cathode slurry

[0345] The dispersant forming the cathode (1120) may include an aqueous dispersant and / or an organic dispersant. For example, it may include N-methyl-2-pyrrolidone. The dispersant forming the cathode (1120) may include an aqueous dispersant and / or an organic dispersant. For example, it may include N-methyl-2-pyrrolidone. Additional examples of aqueous dispersants include sodium dodecyl sulfate (SDS), polyvinylpyrrolidone (PVP), and carboxymethyl cellulose (CMC), and additional organic dispersants include Triton X-100, polyethylene glycol (PEG), and various surfactants such as polysorbates or poloxamers. In some embodiments, the cathode (1120) may be prepared using methods that do not require a dispersant, such as dry powder processing or certain additive manufacturing techniques, although aspects of the present invention are not limited thereto.

[0346]

[0347] Cathode drying technology

[0348] The slurry for the cathode (1120) can be dried by evaporating the solvent using heat, electron beam (E-beam), gamma rays, or UV (G, H, I-line) irradiation, or a combination thereof. For example, the slurry can be vacuum dried at room temperature. During the drying step, the solvent is removed by evaporation, but other components remain intact and form the cathode (1120). In addition to the drying techniques mentioned, several other methods can be used to dry the cathode slurry. These additional techniques can offer various advantages depending on the specific material, production requirements, and desired electrode properties.

[0349] Infrared (IR) drying can be used to rapidly heat the electrode surface, promoting efficient solvent evaporation. This method can be particularly effective for thin electrode coatings and can enable precise control of the drying process. Microwave drying is another option that can provide volumetric heating of the electrode material, allowing for more uniform drying across the electrode thickness. In some cases, a combination of convection and microwave drying can be used to optimize both drying speed and uniformity.

[0350] Freeze-drying, also known as lyophilization, can be used for certain electrode formulations. This process involves freezing the slurry and then sublimating the solvent under vacuum conditions. Freeze-drying can help maintain the porous structure of the electrode, which can be beneficial for electrolyte penetration and ion transport.

[0351] Supercritical CO2 drying is an advanced technique that can be used for specialized electrode materials. This method involves replacing the solvent with liquid CO2, then bringing it to a supercritical state and discharging it. This approach can help preserve the delicate nanostructures within the electrode and is particularly useful for aerogel-based electrodes.

[0352] In some cases, a two-step drying process may be used. For example, an initial drying step may be performed at a low temperature to remove bulk solvent, followed by a higher temperature step to remove residual solvent and potentially initiate desired chemical reactions within the electrode material, although aspects of the present invention are not limited thereto.

[0353] Ultrasonic drying may also be considered for certain electrode formulations. This technique uses high-frequency sound waves to agitate solvent molecules, potentially accelerating the drying process and improving solvent removal from the porous structure within the electrode.

[0354]

[0355] Solid electrolyte layer general

[0356] The solid electrolyte layer (106) is suitable for lithium ion diffusion between the positive electrode (1130) and the negative electrode (1120). The solid electrolyte layer (106) provides an electrically conductive path for charge carrier movement between the positive electrode (1130) and the negative electrode (1120). The solid electrolyte layer (106) is in electrical communication with the positive electrode (1130) and the negative electrode (1120). In an embodiment, the solid electrolyte layer (106) is formed on and in direct contact with the positive electrode (1130) or the negative electrode (1120). In an embodiment, the solid electrolyte layer (106) is in direct contact with the positive electrode (1130) and the negative electrode (1120). In other embodiments, other functional layers may be interposed between the solid electrolyte layer (106) and the positive electrode (1130) and / or the negative electrode (1120).

[0357] The solid electrolyte layer may have a gradient structure with varying composition or properties across its thickness, thereby optimizing ion transport and interfacial compatibility. For example, the layer may have higher ionic conductivity near the electrodes and higher mechanical strength in the middle, but aspects of the present invention are not limited thereto.

[0358] In some embodiments, the solid electrolyte layer may be formed as a composite incorporating both ceramic and polymer components to balance mechanical properties and ionic conductivity. The ceramic component provides structural stability, while the polymer can enhance flexibility and electrode contact.

[0359] The solid electrolyte layer may contain porosities or channels designed to facilitate ion transport while maintaining mechanical integrity. This can be created using techniques such as freeze casting or templating.

[0360] In certain configurations, the solid electrolyte layer may be applied in several thin sublayers with slightly different compositions or properties, allowing fine tuning of the overall layer properties.

[0361] The interface between the solid electrolyte and the electrode can be modified through surface treatments or the addition of buffer layers to improve adhesion and reduce interfacial resistance. This may involve plasma treatment, chemical modification, or the deposition of nanoscale interfacial layers.

[0362] In some embodiments, the solid electrolyte layer may possess self-healing properties. This can be achieved, for example, by incorporating microcapsules containing electrolyte material capable of repairing small cracks or defects that may form during cycling.

[0363] The solid electrolyte layer can be designed to have anisotropic properties, such that it has different ionic conductivities in different directions to optimize ion transport between the electrodes while minimizing unwanted side reactions.

[0364] In certain configurations, the solid electrolyte layer may include an inserted current collector or conductive mesh to improve charge transfer and distribution throughout the battery structure.

[0365] Solid electrolyte layers can be formulated to have temperature-dependent properties to optimize performance over a wide range of operating conditions. This may include phase-change materials or components with different coefficients of thermal expansion.

[0366] In some embodiments, the solid electrolyte layer can be designed to be pressure sensitive, thereby improving ionic conductivity and enhancing performance under moderate compression during battery operation.

[0367]

[0368] Materials for solid electrolyte layers

[0369] The solid electrolyte layer (106) may be capable of transporting lithium ions. The material of the solid electrolyte layer (106) is not particularly limited as long as it allows adhesion to adjacent layers, has appropriate electrical conductivity, and does not cause significant chemical changes in the voltage range of the all-solid-state battery (1101). For example, in addition to the composite solid electrolyte material including the additive materials provided herein and the sulfide-containing solid electrolyte material, the solid electrolyte layer (106) may include, but is not limited to, various inorganic solid electrolytes, polymer solid electrolytes, and polymer gel electrolytes. Additionally or alternatively, the solid electrolyte layer (106) may include, but is not limited to, ceramic electrolytes, glass electrolytes, hybrid organic-inorganic electrolytes, and nanostructured electrolytes.

[0370]

[0371] Inorganic solid electrolyte

[0372] The inorganic solid electrolyte may include, but is not limited to, a crystalline solid electrolyte, an amorphous solid electrolyte, a glass ceramic solid electrolyte, the like, or a combination thereof. The inorganic solid electrolyte may be sulfide-based, oxide-based, the like, or a combination thereof. In addition to sulfide-based and oxide-based inorganic solid electrolytes, other types of inorganic solid electrolytes may include halide-based electrolytes, nitride-based electrolytes, and borate-based electrolytes. For example, lithium-rich semi-perovskites (LiRAPs), such as Li3OCl and Li3OBr, lithium nitride (Li3N), and lithium borohydride (LiBH4), have been studied as potential solid electrolyte materials for lithium ion batteries, but aspects of the present invention are not limited thereto.

[0373]

[0374] Sulfide-based solid electrolyte

[0375] As provided herein, the sulfide-based solid electrolyte comprises sulfur (S) and has the ionic conductivity of a metal belonging to Group I or Group II of the periodic table, and may comprise a Li-PS-based glass or a Li-PS-based glass ceramic. For example, the sulfide-based solid electrolyte may comprise lithium sulfide, silicon sulfide, germanium sulfide, and boron sulfide. A specific example of an inorganic solid electrolyte is Li 3.833 Sn 0.833 As 0.166 S4, Li4SnS4, Li 3.25 Ge 0.25 P 0.75 S4, Li2S—P2S0, B2S3—Li2S, XLi2S-(100x)P2S 5　 (x=7080), Li2S—SiS2—Li3N, Li2S—P2S5—LiI, Li2S—SiS2—LiI, Li2S—B2S3—LiI, Li3N, LISICON, LIPON (Li 3+y PO 4-x N x ), thio-LISICON (Li 3.25 Ge 0.25 P 0.75 S4), Li2O—Al2O3—TiO2—P2O 5　 (LATP), Li2S—P2S5, Li2S—LiI—P2S5, Li2S—LiI—Li2O—P2S5, Li2S—LiBr—P2S5, Li2S—Li2O—P2S5, Li2S—Li3PO4—P2S5, Li2S—P2S5—P2O5, Li2S—P2S5—SiS2, Li2S―P2S5―SnS, Li2S―P2S5―Al2S3, Li2S―GeS2, Li2S―GeS2―ZnS, Li10GeP2S 12 (LGPS), Li7P3S 11 , Li6PS5Cl, Li6PS5Br, Li6PS5I, Li 9.54 Si 1.74 P 1.44 S 11.7 Cl 0.3 , Li 11 Si2PS 12, similar ones, or combinations thereof. In some cases, Al-doped Li 10 GeP2S 12 Doped variants of these materials, such as Sb-doped Li6PS5Cl, may also be used to further enhance ionic conductivity or stability, but aspects of the present invention are not limited thereto.

[0376]

[0377] Oxide-based solid electrolyte

[0378] Oxide-based solid electrolyte materials contain oxygen (O) and have the ionic conductivity of metals belonging to group I or II of the periodic table. Oxide-based solid electrolyte materials include LLTO-based compounds, Li6La2CaTa2O 12 , Li6La2ANb2O 12 (A is Ca or Sr), Li2Nd3TeSbO 12 , Li3BO 2.5 N 0.5 , Li9SiA1O8, LAGP-based compounds, LATP-based compounds, Li 1+x Ti 2-x Al x Si y (PO4) 3-y (0≤x≤1, 0≤y≤1), LiAl x Zr 2-x (PO4)3(0≤x≤1, 0≤y≤1), LiTi x Zr 2x (PO4)3(0≤x≤1, 0≤y≤1), LISICON-based compounds, LIPON-based compounds, perovskite-based compounds, NASICON-based compounds, and LLZO-based or derived compounds (e.g., Al-doped Li7La3Zr2O 12 and Ta-doped Li7La3Zr2O 12) may include at least one selected from the group consisting of Li3OCl and Li3OBr. Lithium-rich semi-perovskites, such as Li3OCl and Li3OBr, have also been studied as potential oxide-based solid electrolytes. In some cases, composite oxide electrolytes combining multiple oxide materials, such as LLZO-LATP composites, can be used to take advantage of the advantages of different oxide systems.

[0379]

[0380] polymer solid electrolyte

[0381] The polymer solid electrolyte is a composite of an electrolyte salt and a polymer resin and has lithium ion conductivity. The polymer solid electrolyte may include a polyether polymer, a polycarbonate polymer, an acrylate polymer, a polysiloxane polymer, a phosphazene polymer, a polyethylene derivative, an alkylene oxide derivative, a phosphoric acid polymer, polyazitated lysine, a polyester sulfide, polyvinyl alcohol, polyvinylidene fluoride, a polymer containing an ionically dissociable group, poly(ethylene imine) (PEI), poly(methyl methacrylate) (PMMA), poly(acrylonitrile) (PAN), poly(ethylene succinate) (PES), a biopolymer such as chitosan and a cellulose derivative, the like, or a combination thereof. The solid polymer electrolyte may include, but is not limited to, a polymer resin such as a branched copolymer comprising a polyethylene oxide (PEO) backbone and a comonomer comprising an amorphous polymer (e.g., PMMA, polycarbonate, polydiloxane (PDMS), and / or phosphazene), a comb polymer, a cross-linked polymer resin, polyethylene glycol (PEG), polypropylene oxide (PPO), polyacrylonitrile (PAN), poly(methyl methacrylate) (PMMA), poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), poly(ethylene oxide-co-propylene oxide) (PEO-PPO), poly(ethylene imine) (PEI), poly(vinyl pyrrolidone) (PVP), poly(vinyl alcohol) (PVA), various block copolymers or graft copolymers comprising these materials, the like, or combinations thereof.

[0382]

[0383] polymer gel electrolyte

[0384] Polymer gel electrolytes can be formed by incorporating an organic electrolyte, an ionic liquid, a monomer, or an oligomer, including an organic solvent and an electrolyte salt, into a polymer resin. The polymer resin for the polymer gel can include a polyether polymer, a PVC polymer, a PMMA polymer, polyacrylonitrile (PAN), polyvinylidene fluoride (PVDF), poly(vinylidene fluoride-co-hexafluoropropylene: PVDF-co-HFP), the like, or a combination thereof. Examples of polymer gel electrolytes that may be suitable for all-solid-state batteries include poly(ethylene oxide) (PEO), poly(methyl methacrylate-co-ethyl acrylate) (PMMA-EA), poly(acrylonitrile-co-methyl methacrylate) (PAN-MMA), poly(vinyl acetate) (PVAc), poly(ethylene glycol diacrylate) (PEGDA), poly(vinyl pyrrolidone) (PVP), poly(ethylene glycol methyl ether acrylate) (PEGMEA), poly(ethylene glycol methyl ether methacrylate) (PEGMEMA), poly(ionic liquid) (PIL), poly(ethylene glycol-co-propylene glycol) (PEG-PPG), poly(vinyl alcohol-co-ethylene) (PVA-PE), poly(acrylamide) (PAM), poly(2-hydroxyethyl methacrylate) (PHEMA), poly(ethylene glycol-co-polyethylene). There are gel electrolytes based on poly(ethylene glycol) oxide (PEG-PEO) and poly(methacrylic acid) (PMAA), which can optimize the electrochemical and physical properties of solid electrolytes.

[0385]

[0386] electrolyte salt

[0387] The electrolyte salt is an ionizable lithium salt and is Li + X - can be expressed as X - is F - , Cl - , Br - , NO3 - , N(CN)2 - , BF4 -, ClO4 - , AlO4 - , AlCl4 - , PF6 - , SbF6 - , AsF6 - , BF2C2O4 - , BC4O8 - , (CF3)2PF4 - , (CF3)3PF3 - , (CF3)4PF2 - , (CF3)5PF - , (CF3)6P - , CF3SO3 - , C4F9SO3 - , CF3CF2SO3 - , (CF3SO2)2N - , (F2SO2)2N - , CF3CF2(CF3)2CO - , (CF3SO2)2CH - , CF3(CF2)7SO3 - , CF3CO2 - , CH3CO2 - , SCN - , (CF3CF2SO2)2N - and the like. For example, lithium salts may include anions selected from the group consisting of LiTFSI, LiCl, LiBr, LiI, LiClO4, lithium tetrafluoroborate (LiBF4), LiB 10 Cl 10, lithium hexafluorophosphate (LiPF6), LiAsF6, LiSbF6, LiAlCl4, LiSCN, LiCF3CO2, LiCH3SO3, LiCF3SO3, LiN(SO2CF3)2, LiN(SO2C2F5)2, LiC4F9SO3, LiC(CF3SO2)3, (CF3SO2)2NLi, lithium chloroborate, lithium lower aliphatic carboxylate, lithium imide 4-phenylborate, lithium bis(oxalato)borate (LiBOB), lithium difluoro(oxalato)borate (LiDFOB), lithium bis(fluorosulfonyl)imide (LiFSI), lithium 4,5-dicyano-2-(trifluoromethyl)imidazolide (LiTDI), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), and lithium bis(fluorosulfonyl)imide (LiFSI), Any one selected from the group consisting of similar ones. The electrolyte salt may include a combination of the salts described herein, but aspects of the present invention are not limited thereto.

[0388]

[0389] Amount of electrolyte salt

[0390] The solid electrolyte layer (106) can include 0, 50, 60, 70, 80, 100, 200, 300, or 400 parts by weight of the electrolyte salt (if present), based on the total weight of the solid electrolyte layer (106). In an embodiment, the electrolyte salt of the solid electrolyte layer (106) can be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it can be between 0 parts by weight and 400 parts by weight, or between 60 parts by weight and 400 parts by weight.

[0391]

[0392] Ionic conductivity of the solid electrolyte layer

[0393] The solid electrolyte layer (106) may have suitable reduction stability and / or ionic conductivity. Since the solid electrolyte layer (106) primarily functions to transfer lithium ions between the electrodes, the solid electrolyte layer (106) may have 10 -7 S / cm, 10 -6 S / cm, 10 -5 S / cm, or 10 -4 It may include a desirable ionic conductivity of S / cm or more.

[0394]

[0395] Thickness of the solid electrolyte layer

[0396] The thickness t6 of the solid electrolyte layer (106) may be 3, 5, 10, 15, 20, 25, 30, 50, 70, 100, 150, 200, 300, 400, 500, or 1,000 μm. In an embodiment, the thickness t6 of the solid electrolyte layer (106) may be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it may be between 5 μm and 1,000 μm, between 30 μm and 100 μm, or between 30 μm and 50 μm.

[0397]

[0398] semi-finished products

[0399] The cell (1001) shown in FIG. 24 may be provided as a semi-finished product. In an embodiment, the cell (1001) is stored, transported, and / or delivered to a reseller, customer, or similar person who completes the manufacture of a battery assembly or product comprising the cell (1001). In another embodiment, the cell (1001) is a finished battery assembly or product.

[0400]

[0401] Battery sealing

[0402] The manufacturing of the all-solid-state battery (1101) can be completed by sealing the housing (1112) of the all-solid-state battery so that it can operate as a battery. The sealing process can involve various techniques to protect the internal components from external environmental factors and maintain the integrity of the battery structure. For example, the housing (1112) can be sealed using methods such as laser welding, ultrasonic welding, or adhesive bonding, although aspects of the present invention are not limited thereto. In some cases, the sealing process can include the introduction of a protective atmosphere or the removal of air to create a vacuum. This sealing step can help prevent moisture ingress, which can potentially degrade the performance of the sulfide-based solid electrolyte. Additionally, the sealing process can incorporate safety features, such as a pressure relief mechanism to manage potential gas buildup during battery operation. Once properly sealed, the all-solid-state battery (1101) is ready for final quality control testing, which can include electrical testing, leak detection, and visual inspection. After passing these tests, the solid-state battery (1101) can be packaged and sold as a finished product for integration into various electronic devices, electric vehicles, energy storage systems, etc.

[0403]

[0404] Battery configuration

[0405] The solid-state battery (1101) is available in a variety of configurations to suit various applications and device requirements. In some cases, the battery may be manufactured in a cylindrical shape, which may be advantageous for certain types of portable electronic devices or automotive applications. Alternatively, the solid-state battery (1101) may be manufactured in a prismatic shape, which may allow for more efficient space utilization in rectangular devices. In other cases, a pouch shape may be used, which provides flexibility in shape and potentially reduces overall battery weight. A pouch shape may be particularly suitable for solid-state batteries because it allows for easier application and control of uniform pressure within the battery. The choice of configuration may depend on factors such as the intended use, space constraints, thermal management requirements, and manufacturing considerations. In some embodiments, hybrid or customized configurations that combine various form factors may be utilized to meet specific design requirements. The diversity of battery form factors allows for the integration of solid-state batteries into a wide range of products, from small wearable devices to large-scale energy storage systems.

[0406]

[0407] voltage

[0408] The solid-state battery (1101) is configured to output a voltage of 1, 2, 3, 4, 5, 6, 10, 12, 20, 24, 30, 40, 48, 50, 60, 70, 80, 90, 96, 100, 200, 300, 400, or 500 V DC. In an embodiment, the output voltage of the solid-state battery (1101) may be within a range formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it may be between 1 V DC and 500 V DC.

[0409]

[0410] volume

[0411] The all-solid-state battery (1101) is configured to have a specific capacity of at least 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, or 300 mAh / g. In an embodiment, the output voltage of the all-solid-state battery (1101) may have a capacity formed by selecting any two numbers from all numbers listed in the immediately preceding sentence. For example, it may be between 100 mAh / g and 300 mAh / g.

[0412]

[0413] Volume expansion calculation

[0414] The all-solid-state battery (1101) may include a desirable volume expansion ratio. The volume expansion ratio can be calculated from the amount of increased thickness after the first charge and discharge cycle compared to the initial thickness. The volume expansion ratio refers to the ratio of the change in thickness after the first charge and discharge cycle to the initial thickness of a particular element. The first charge and discharge cycle is performed by CC-CV charging the battery at 0.1 C and cutting it at 4.25 to 4.4 V and 0.02 C, and CC discharging the battery at 0.1 C and cutting it at 3 V. The volume expansion ratio is calculated by Equation 1 below, where A represents the thickness before charge and discharge and B represents the thickness after charge and discharge. The thickness can be measured using a Mauser micrometer or a scanning electron microscope (SEM).

[0415]

[0416] Equation 1: Volume expansion rate = [(BA) / A] × 100 C-Rate

[0417]

[0418] The C-rate used here refers to the rate at which a battery discharges to its maximum capacity. For example, a 1C rate refers to the discharge current that can discharge the entire battery in one hour. For example, for a battery with a capacity of 20 Amp-hrs, the discharge current at 1C is 20 Amps, but aspects of the present invention are not limited thereto.

[0419] Other exemplary methods for measuring and calculating the volumetric expansion of all-solid-state batteries may include volumetric expansion measurements (e.g., gas pycnometry), in situ dilatometry, X-ray tomography, strain gauge measurements, optical methods (e.g., digital image correlation or laser interferometry), pressure-based methods, and electrochemical strain microscopy.

[0420] Although several examples have been provided above, those skilled in the art will be able to appropriately modify and implement all aspects of the present invention by omitting, changing or replacing all or part of the configuration of the present invention or adding other components without departing from the technical spirit of the present invention by referring to this specification and the accompanying drawings.

[0421] The terms and expressions used herein are to be interpreted broadly and not in a restrictive sense. The word "include" as used herein does not exclude the presence or addition of other components in addition to the components mentioned.

[0422] Anything expressed in the singular here includes the plural unless the context clearly indicates otherwise.

[0423] The exemplary aspects of the present invention may be combined with one another, and what is described with respect to a particular aspect may be equally applied to other aspects, unless contradictory.

[0424] Having thus described the features of the present invention, it will be apparent that the invention can be modified in various ways. Such modifications should not be considered as a departure from the spirit and scope of the invention, and all such modifications apparent to those skilled in the art are intended to be included within the scope of the following claims.

Claims

1. As a battery cell pressurization system, A sealed case having an inner chamber, the sealed case including at least one window allowing visual inspection of the inner chamber; A pouch-shaped battery cell placed within an inner chamber of the sealed case; A fluid filling the inner chamber and surrounding the pouch-shaped battery cell; A fluid inlet in fluid communication with the inner chamber; A pressurizing member configured to control the pressure of the fluid within the internal chamber so that the pressure at which the fluid pressurizes the pouch-type battery cell is from 1 MPa to 10 MPa; a heater configured to heat a fluid within the inner chamber; and A pressure measuring member configured to measure the pressure within the inner chamber, The above fluid is used to charge the pouch-type battery cell. A battery cell pressurization system for isotropically pressurizing the pouch-shaped battery cell during at least one of the discharges.

2. In paragraph 1, A battery cell pressurization system wherein the fluid is a gas or liquid.

3. In paragraph 2, The above fluid is a battery cell pressurization system in which air is present.

4. In paragraph 1, A battery cell pressurization system further comprising a wire member configured to input and output an electric signal of the pouch-type battery cell.

5. In paragraph 1, The above sealed case is a battery cell pressurization system having a cylindrical shape or a square shape.

6. In paragraph 1, The sealed case is a battery cell pressurization system comprising metal.

7. In paragraph 6, A battery cell pressurization system wherein the metal comprises at least one of aluminum (Al), stainless steel (SUS), titanium (Ti), nickel (Ni), iron (Fe), and copper (Cu).

8. In paragraph 1, The above pouch-type battery cell is a battery cell pressurization system that is a lithium secondary battery.

9. In paragraph 1, The above pouch-type battery cell is a battery cell pressurization system having a separator containing a solid electrolyte (SSE).

10. In paragraph 1, The above pouch-type battery cell is a battery cell pressurization system that is an all-solid-state battery (ASSB).

11. A battery pack comprising a battery cell pressurization system according to paragraph 1.

12. In paragraph 11, A battery pack further comprising two or more pouch-type battery cells including the above pouch-type battery cells.

13. In paragraph 11, The above sealed case is a battery pack comprising aluminum having a thickness of about 0.5 mm.

14. As a battery cell pressurization device, A case having an internal space for accommodating battery cells and fluid; At least one fluid inlet or outlet through which fluid is introduced into or discharged from the case; and Includes a pressurized member, The above pressurizing member controls the pressure inside the case, A battery cell pressurizing device in which, when the fluid and the battery cell are inside the case, the pressurizing member controls the pressure of the fluid so that an isostatic pressure is applied to the battery cell, and the isostatic pressure is less than 10 MPa.

15. In paragraph 14, A battery cell pressurizing device wherein the fluid isotropically pressurizes the battery cell during at least one of charging and discharging of the battery cell.

16. In paragraph 14, A battery cell pressurization device further comprising at least one window allowing visual inspection of the interior space of the case.

17. In paragraph 14, A battery cell pressurization device wherein the battery cell is a lithium secondary battery including a separator of a solid electrolyte (SSE).

18. In paragraph 14, The above battery cell is a battery cell pressurization device that is an all-solid-state battery (ASSB).

19. As a battery cell pressurization device, A case having at least one window; A fluid filling the interior of the case; a battery cell located inside the case; and A pressurizing member configured to control the pressure inside the case using the fluid so that the fluid generates an isostatic pressure of about 10 MPa or less in the battery cell, The above pressurizing member is a battery cell pressurizing device that cycles the pressure applied to the battery cell inside the case between about 1 MPa and 5 MPa.

20. In paragraph 19, A battery cell pressurizing device wherein the pressurizing member controls pressure so that the fluid isotropically pressurizes the battery cell during at least one of charging and discharging of the battery cell.

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