Electrode assembly and electrochemical device including the electrode assembly

Abstract

This invention relates to an electrode assembly with a novel structure and an electrochemical device including the electrode assembly. The electrode assembly includes: a first unit comprising at least one first single cell; a second unit comprising at least one second single cell; and an insulating film disposed between the first unit and the second unit, wherein the first unit and the second unit are connected in series to achieve a high nominal voltage and high energy density. According to one aspect of this disclosure, an advantageous effect is that the nominal voltage of the electrochemical device can be increased while minimizing the construction of auxiliary components of the electrochemical device.

Description

Technical Field

[0001] This disclosure relates to an electrode assembly for an electrochemical device and an electrochemical device including the electrode assembly.

[0002] This application is based on and claims priority to Korean Patent Application No. 2024-0133079, filed on September 30, 2024, the disclosure of which is incorporated herein by reference in its entirety. Background Technology

[0003] Recently, with the increasing air pollution caused by the use of fossil fuels and the development of alternative energy sources driven by energy depletion, the demand for electrochemical devices capable of storing generated electrical energy has been growing. Rechargeable electrochemical devices are being used in everyday life across a wide range of applications, including mobile devices, electric vehicles, and hybrid electric vehicles.

[0004] Electrochemical devices are essential in modern society as a source of energy for many different types of electronic devices, and the required capacity is increasing with the growing usability and complexity of mobile devices and the development of electric vehicles. To meet user needs, small devices use multiple individual battery cells, while vehicles or other large devices use battery modules or battery packs that include multiple battery cells with electrical connections.

[0005] Meanwhile, the pouch-type electrochemical device includes an electrode assembly and a sealed housing containing the electrode assembly, and the electrode assembly has different types, such as a jelly roll electrode assembly, a stacked electrode assembly, a stacked folded electrode assembly, or a laminated stacked electrode assembly. The jelly roll electrode assembly has a structure in which the elongated negative electrode and the elongated positive electrode are wound with a separator placed between them. The stacked electrode assembly includes a single cell, each cell including a rectangular positive electrode and a rectangular negative electrode stacked with a separator placed between them. The stacked folded electrode assembly includes a single cell wound with a long separation membrane. The laminated stacked electrode assembly includes single cells stacked and attached with a separator placed between them.

[0006] Commonly known electrode assemblies have a structure in which multiple monocells are stacked, each monocell comprising, in order from bottom to top, a separator, a negative electrode, a separator, and a positive electrode, with a half cell having a negative electrode sandwiched between a pair of separators at the top. Furthermore, all negative and positive electrodes are connected in parallel to form negative and positive terminals, respectively.

[0007] The aforementioned electrode assembly can increase battery capacity by increasing the number of individual cells stacked in a single battery cell, but cannot increase the nominal voltage because all negative and positive electrodes are connected in parallel. Summary of the Invention

[0008] Technical issues

[0009] This disclosure is designed to solve the above-mentioned problems, and therefore this disclosure is intended to provide: Electrochemical devices with high energy density and high voltage performance.

[0010] Specifically, one aspect of this disclosure aims to provide an electrode assembly for a battery and an electrochemical device including the electrode assembly, the electrode assembly having a high voltage with a minimal number of auxiliary components to achieve the high energy density advantage of a lithium electrochemical device.

[0011] More specifically, one aspect of this disclosure aims to provide an electrochemical device that has high voltage performance with a minimal number of auxiliary components and a single package.

[0012] Technical solution

[0013] In order to achieve the above objectives, According to one aspect of this disclosure, an electrode assembly is provided according to the following embodiments.

[0014] The electrode assembly according to the first embodiment includes: The first unit includes at least one first single cell. The second unit, the second unit comprising at least one second single-cell battery; and An insulating film, which is positioned between the first unit and the second unit, The first unit and the second unit are connected in series.

[0015] According to the second embodiment, in the first embodiment... The first unit may include two or more first single-cell batteries connected in parallel, and The second unit may include two or more second single-cell batteries connected in parallel.

[0016] According to the third embodiment, in the first or second embodiment... Each electrode tab in the first and second units may be located on the same shorter side of the electrode assembly.

[0017] According to the fourth embodiment, in any one of the first to third embodiments, The first electrode terminal in the first unit and the second electrode terminal in the second unit can be positioned such that they overlap at least partially based on the stacking direction of the first unit and the second unit.

[0018] The first electrode and the second electrode can have different polarities.

[0019] According to the fifth embodiment, in any one of the first to fourth embodiments, The electrode assembly may include a welding section where a first electrode terminal piece in the first unit and a second electrode terminal piece in the second unit are welded together.

[0020] The first electrode and the second electrode can have different polarities.

[0021] According to the sixth embodiment, in any one of the first to fifth embodiments, The first single cell may include a first negative electrode, a first separator, and a first positive electrode stacked in sequence. The second single cell may include a second positive electrode, a second separator, and a second negative electrode stacked in sequence, and The welded portion can be formed in the following ways: Solder the terminal block of the first positive electrode to the terminal block of the second negative electrode, or Solder the terminal block of the first negative electrode and the terminal block of the second positive electrode.

[0022] According to the seventh embodiment, in any one of the first to sixth embodiments, The electrode assembly may further include a sealing portion that seals the welded portion.

[0023] According to the eighth embodiment, in any one of the first to seventh embodiments, The electrode assembly may include an equal number of first single-cell cells and second single-cell cells.

[0024] According to the ninth embodiment, in any one of the first to eighth embodiments, The insulating film may have openings for contact between the first electrode tab in the first unit and the second electrode tab in the second unit.

[0025] According to another aspect of this disclosure, an electrochemical device according to the following embodiments is provided.

[0026] The electrochemical device according to the tenth embodiment includes: The electrode assembly according to any one of the first to ninth embodiments, Electrolytes, and A housing that contains the electrode assembly and the electrolyte.

[0027] According to the eleventh embodiment, in the tenth embodiment, The electrochemical device may include electrode leads connected to each electrode tab, the electrode tabs being positioned such that they do not overlap based on the stacking orientation of the first and second units.

[0028] According to the twelfth embodiment, in the tenth or eleventh embodiment, The electrochemical device may include a welding section where the first electrode terminal piece in the first unit and the second electrode terminal piece in the second unit are welded together.

[0029] The electrochemical device may further include an insulating portion located at the position where the welded portion touches the inside of the housing.

[0030] According to the thirteenth embodiment, in any one of the tenth to twelfth embodiments, The electrochemical device may further include a sealing portion for sealing the outer periphery of the housing.

[0031] According to the fourteenth embodiment, in any one of the tenth to thirteenth embodiments, The shell can be a bag-shaped shell.

[0032] Beneficial effects

[0033] The electrode assembly according to embodiments of the present disclosure has the effect of realizing an electrochemical device with high voltage performance in a single package.

[0034] Specifically, compared to the nominal voltage Vn of a single cell, there is an effect of providing an electrochemical device with a nominal voltage of n×Vn by using n single cells. Attached Figure Description

[0035] Figure 1 This is a side view of a first single-cell battery 100 according to an embodiment of the present disclosure.

[0036] Figure 2 This is a side view of a first single-cell battery 100 according to an embodiment of the present disclosure.

[0037] Figure 3 This is a side view of a second single-cell battery 200 according to an embodiment of the present disclosure.

[0038] Figure 4 This is a side view of a second single-cell battery 200 according to an embodiment of the present disclosure.

[0039] Figure 5 This is an exploded perspective view of a first single cell 100 according to an embodiment of the present disclosure and an exploded perspective view of a first unit including two or more stacked first single cell 100s.

[0040] Figure 6 This is an exploded perspective view of a second single cell 200 according to an embodiment of the present disclosure and an exploded perspective view of a second unit including two or more stacked second single cell 200s.

[0041] Figure 7 This is an exploded perspective view of electrode assembly 1 according to an embodiment of the present disclosure.

[0042] Figure 8 It is shown Figure 7 A diagram showing the position of the electrode lead 400 in electrode assembly 1.

[0043] Figure 9 This is a diagram of an assembled electrode assembly 1 according to an embodiment of the present disclosure.

[0044] Figure 10 This is a diagram illustrating the assembly process of placing the electrode assembly 1 in a pouch-type housing 500 according to an embodiment of the present disclosure.

[0045] Figure 11 This is a diagram illustrating an assembled electrochemical device according to an embodiment of the present disclosure. Detailed Implementation

[0046] This disclosure will be described in detail below.

[0047] When used in this specification, the terms “comprising,” “including,” or “having” refer to the presence of the said element, but do not exclude the presence or addition of one or more other elements unless the context clearly indicates otherwise.

[0048] In this specification, "A and / or B" means A or B or both.

[0049] In this specification, terms indicating directions such as up, down, left, right, inside, or outside are used for convenience, but are not intended to limit this disclosure.

[0050] This disclosure relates to an electrode assembly and an electrochemical device including the electrode assembly.

[0051] In this disclosure, the electrochemical device is a device that converts chemical energy into electrical energy through an electrochemical reaction, and encompasses the concepts of primary and secondary batteries. Secondary batteries are rechargeable and encompass the concepts of lithium-ion batteries, nickel-cadmium batteries, or nickel-metal hydride batteries.

[0052] Electrode assembly

[0053] An electrode assembly according to one aspect of this disclosure includes two or more individual cell units connected in series.

[0054] Specifically, the electrode assembly 1 includes: a first unit including at least one first single cell 100; a second unit including at least one second single cell 200; and an insulating film 300 located between the first unit and the second unit.

[0055] According to one aspect of this disclosure, a "monocell" refers to a single cell comprising electrodes of different polarities stacked with spacers placed between the electrodes. For example, a monocell may refer to a stack in which the negative electrode, spacers, and positive electrode are stacked sequentially along the thickness direction. Additionally, a monocell may also include spacers on the top and / or bottom of the stack.

[0056] Conversely, in this specification, "half cell" refers to a stack comprising electrodes of one polarity between separators. For example, a half cell may refer to a stack having a separator / negative electrode / separator or a separator / positive electrode / separator structure.

[0057] In embodiments of this disclosure, a "unit" refers to a structure comprising one or more individual battery cells. The unit may comprise a single battery cell, or it may be a structure comprising two or more single battery cells stacked along the thickness direction. Furthermore, the unit may be a structure comprising a single battery cell and a half-cell. Alternatively, the unit may be a structure comprising two or more single battery cells stacked along the thickness direction and further comprising a half-cell at the top and / or bottom. In other words, the "unit" may be referred to as a stacked cell. For example, a first unit may be referred to as a first stacked cell, and a second unit may be referred to as a second stacked cell.

[0058] Therefore, the electrode assembly according to one aspect of this disclosure can have a structure comprising two stacked battery cells connected in series with an insulating film located between the two stacked battery cells.

[0059] In this specification, each of the first single-cell and the second single-cell is a term describing a single-cell cell present on the left or right or top or bottom sides relative to the insulating film, and the detailed structure and / or composition of the first single-cell and the second single-cell may be the same or different, and this disclosure is not limited thereto. In this specification, for ease of description, the electrodes, positive electrode, negative electrode, and separator included in the first single-cell may be referred to as the first electrode, the first positive electrode, the first negative electrode, and the first separator, and the electrodes, positive electrode, negative electrode, and separator included in the second single-cell may be referred to as the second electrode, the second positive electrode, the second negative electrode, and the second separator.

[0060] In this specification, unless otherwise specified, an "electrode" can be either a positive or a negative electrode. Furthermore, positive and negative electrodes may include common components, and their descriptions are omitted.

[0061] Figure 1 and Figure 2 Each is a side view of a first single-cell battery 100 according to an embodiment of the present disclosure. (See also...) Figure 1 The first single-cell battery 100 includes a first negative electrode 110, a first separator 130, and a first positive electrode 120 stacked sequentially along the thickness direction. (Reference) Figure 2 The first single cell 100 may include a first separator 130, a first negative electrode 110, a first separator 130 and a first positive electrode 120 stacked sequentially along the thickness direction.

[0062] Figure 3 and Figure 4 Each is a side view of a second single-cell battery 200 according to an embodiment of the present disclosure. (See also...) Figure 3 The second single-cell unit 200 includes a second positive electrode 220, a second separator 230, and a second negative electrode 210 stacked sequentially along the thickness direction. (Reference) Figure 4 The second single cell 200 may include a second separator 230, a second positive electrode 220, a second separator 230, and a second negative electrode 210 stacked sequentially along the thickness direction.

[0063] In this specification, "thickness direction" refers to the stacking direction of the negative electrode, separator, and positive electrode within the electrode assembly. Furthermore, "thickness direction" can be matched with the stacking direction of the first single cell within the first unit, the stacking direction of the second single cell within the second unit, or the stacking direction of the first unit, insulating film, and second unit within the electrode assembly.

[0064] Figure 5 This is a diagram illustrating a first cell formed by stacking p (an integer of 1 ≤ p) first single-cell units 100 according to an embodiment of the present disclosure. Reference Figure 5The stacking direction of the p first single cell cells within the first unit can be the thickness direction of the electrode assembly.

[0065] Figure 6 This is a diagram illustrating a second cell formed by stacking q (an integer of 1 ≤ q) second single-cell units 200 according to an embodiment of the present disclosure. Reference Figure 6 The stacking direction of the q second single cells in the second unit can be the thickness direction of the electrode assembly.

[0066] In embodiments of this disclosure, p and q can each be an independent integer of 1 or greater, and preferably, the number of stacked single cells can vary depending on the specifications of the electrochemical device in which electrode assemblies are used. For example, depending on the specifications of the electrochemical device, p and q can each be independently 1 to 200, 5 to 150, 10 to 100, 15 to 90, 20 to 80, 25 to 70, 30 to 60, or 40 to 50, but are not limited thereto.

[0067] In embodiments of this disclosure, the electrode assembly may preferably include an equal number of first single-cell cells and second single-cell cells, but this disclosure is not limited thereto.

[0068] In embodiments of this disclosure, the first unit may include one first single battery cell, or may include two or more first single battery cells. Here, when the first unit includes two or more first single battery cells, the two or more first single battery cells are electrically connected in parallel.

[0069] Similarly, in embodiments of this disclosure, the second unit may include one second single-cell battery, or may include two or more second single-cell battery. Here, when the second unit includes two or more second single-cell battery, the two or more second single-cell battery are electrically connected in parallel.

[0070] Therefore, when the first unit comprises two or more first single-cell batteries, the first positive terminal piece can preferably be included at an overlapping position based on the stacking direction of the first single-cell batteries. Furthermore, the first positive terminal pieces can be connected to each other to form a first positive terminal piece cluster. Similarly, when the first unit comprises two or more first single-cell batteries, the first negative terminal pieces can be included at an overlapping position based on the stacking direction of the first single-cell batteries, and further, can be connected to each other to form a first negative terminal piece cluster.

[0071] In embodiments of this disclosure, in order to prevent short circuits caused by physical contact between the positive and negative electrodes within the first cell, the first positive electrode terminal cluster and the first negative electrode terminal cluster can preferably be placed at non-overlapping positions based on the stacking direction of the first single cell.

[0072] More specifically, the first positive electrode terminal cluster and the first negative electrode terminal cluster can be located on the same shorter side of the first cell, and preferably, they can be placed at a non-overlapping position based on the stacking direction of the first single cell.

[0073] In another embodiment of this disclosure, in the same manner as the first unit, when the second unit includes two or more second single-cell batteries, a second positive terminal cluster and a second negative terminal cluster can be formed, and preferably, the second positive terminal cluster and the second negative terminal cluster can be placed at a non-overlapping position based on the stacking direction of the second single-cell batteries.

[0074] In embodiments of this disclosure, each electrode tab in the first unit and the second unit, or each cluster of electrode tabs in the first unit and the second unit, may preferably be located on the same shorter side of the electrode assembly.

[0075] As described above, the first unit and the second unit may each include a plurality of first single-cell cells or a plurality of second single-cell cells. In the following description, for ease of description, an electrode assembly comprising a first single-cell cell, an insulating film, and a second single-cell cell will be described; however, the electrode assembly may include a first unit comprising two or more stacked first single-cell cells and a second unit comprising two or more stacked second single-cell cells, and the structure of this disclosure is not limited thereto.

[0076] An electrode assembly according to one aspect of this disclosure includes a first unit and a second unit, the first unit including at least one first single cell, and the second unit including at least one second single cell, wherein the first unit and the second unit are connected in series to enable the nominal voltage of the electrode assembly to increase with the number of stacked first and second single cells.

[0077] In this case, the electrode assembly includes: a first unit and a second unit connected in series; and an insulating film for suppressing or preventing the flow of electricity and the migration of electrolytes except at the series connection point between the first unit and the second unit.

[0078] In embodiments of this disclosure, the insulating film is not limited to a specific material and may include any material having insulating properties to electrically separate the first unit from the second unit except at the series connection location. For example, the insulating film may include polyethylene terephthalate (PET), polyimide (PI), polypropylene (PP), polyethylene (PE), polyvinyl chloride (PVC), high-density polyethylene (HDPE), epoxy resin, or a mixture of two or more of the above materials, but this disclosure is not limited thereto.

[0079] Figure 7This is an exploded perspective view of electrode assembly 1 according to an embodiment of the present disclosure. (See reference...) Figure 7 The electrode assembly 1 includes a first unit comprising a first single cell 100 on one side and a second unit comprising a second single cell 200 on the other side, wherein an insulating film 300 is located between the first unit and the second unit. In this case, for the series electrical connection between the first unit and the second unit, the first electrode 120 and the second electrode 210 having opposite polarities can be physically in contact with each other through electrode tabs 121, 211.

[0080] In embodiments of this disclosure, the insulating film 300 may preferably have an opening for physical contact between the first electrode tab and the second electrode tab. For example, refer to... Figure 7 For the series connection and contact between the first positive terminal piece 121 and the second negative terminal piece 211, the insulating film 300 may have an opening at the contact position between the first positive terminal piece 121 and the second negative terminal piece 211.

[0081] According to another embodiment of this disclosure, the first negative electrode terminal 111 in the first single cell and the second positive electrode terminal 221 in the second single cell can be connected in series in the electrode assembly 1 according to the stacking order, but this disclosure is not limited thereto.

[0082] As described above, according to the embodiments of this disclosure, the structure in which the first positive terminal piece 121 and the second negative terminal piece 211 are in contact with each other in the electrode assembly can be represented as follows: when the first single cell and the second single cell respectively include a plurality of first single cells and a plurality of second single cells, the first positive terminal piece cluster and the second negative terminal piece cluster or the first negative terminal piece cluster and the second positive terminal piece cluster are in contact with each other.

[0083] In embodiments of this disclosure, for the series electrical connection of the first unit and the second unit, the first electrode terminal (or cluster of first electrode terminal terminals) in the first unit and the second electrode (or cluster of second electrode terminal terminals) in the second unit can be positioned such that they at least partially overlap based on a stacking orientation. In this case, the first electrode and the second electrode can have different polarities. For example, refer to... Figure 7 The electrode assembly 1 may have a first positive terminal piece 121 and a second negative terminal piece 211 at the overlapping position based on the stacking direction of the electrode assemblies.

[0084] According to embodiments of this disclosure, when the first positive electrode contact 121 and the second negative electrode contact 211 are configured to contact each other, the first negative electrode contact 111 and the second positive electrode contact 221 can preferably be placed in non-overlapping positions based on the stacking direction. More preferably, when manufacturing an electrochemical device, electrode leads can preferably be connected to the electrode contacts placed in non-overlapping positions.

[0085] For example, Figure 8 This illustrates the connection of electrode lead 400 to electrode terminals when an electrochemical device is fabricated using electrode assembly 1. (Reference) Figure 8 The first negative terminal 111 and the second positive terminal 221 can be placed in a non-overlapping position based on the stacking direction, and the negative lead 410 can be connected to the first negative terminal and the positive lead 420 can be connected to the second positive terminal.

[0086] In embodiments of this disclosure, the electrode assembly 1 may include a welding portion 600, which is formed by welding a first electrode tab and a second electrode tab, the first electrode tab and the second electrode tab being positioned such that at least a portion of them overlap based on the stacking direction of the electrode assembly.

[0087] In embodiments of this disclosure, electrode assembly 1 may further include a sealing portion of the welded portion 600 to prevent the welded portion from separating. The sealing portion may include, for example, a material selected from polyolefin-based resins (such as polypropylene, polyethylene, polyacrylic acid, or polybutene), polyurethane resins, polyimide resins, or mixtures thereof that has high chemical resistance and sealing performance, and the material of the sealing portion is not limited thereto, and may include any material used as a sealant for the battery.

[0088] Figure 9 This is an assembly diagram of electrode assembly 1 according to an embodiment of the present disclosure. (See reference...) Figure 9 The electrode terminals that are in contact with each other can be welded and sealed, and electrode leads 410 and 420 can each be positioned at each electrode terminal in a non-overlapping location. However, the electrode assembly can change the position of the electrode terminals with electrode leads and the welding position of the contacting electrode terminals, and this disclosure is not limited to the figures shown herein. For example, according to... Figure 9 Although the solder joint is located at the center of one shorter side of the electrode assembly and the electrode lead is on the outside of the shorter side, as another example, the solder joint may be located on one outside of one shorter side of the electrode assembly and the electrode lead may be located at the center of one shorter side and on the other outside, but this disclosure is not limited thereto.

[0089] Electrochemical device

[0090] According to another aspect of this disclosure, an electrochemical device is provided, which includes the electrode assembly described above.

[0091] Specifically, an electrochemical device may include the aforementioned electrode assembly, electrolyte, and housing containing them.

[0092] Figure 10This is an exploded view of the electrode assembly 1 and the housing for manufacturing the electrochemical device according to an embodiment of the present disclosure. (See reference...) Figure 10 The housing may include an upper housing and a lower housing, and may have a bag-shaped storage space for accommodating electrode assemblies.

[0093] In embodiments of this disclosure, the electrochemical device may include electrode leads 400 connected to each electrode tab located at a non-overlapping position based on the stacking orientation of the first and second units, and each electrode lead 410, 420 may be exposed to the outside of the housing.

[0094] In embodiments of this disclosure, the housing may further include auxiliary components, such as an insulating resin layer, on the inside of the storage space to protect the electrode assembly.

[0095] In this case, according to embodiments of the present disclosure, in order to minimize the number of auxiliary components and reduce the weight of the electrochemical device, more preferably, the electrochemical device may also include an insulating portion 700 at a location where a weld portion 600 between electrode terminals in the electrode assembly that are in contact with each other touches the inside of the housing.

[0096] refer to Figure 10 Preferably, the insulating part 700 can be present in both the upper and lower housings to improve the safety of the electrochemical device.

[0097] In embodiments of this disclosure, preferably, the electrochemical device may further include a sealing portion 800 to seal at least a portion of the outer periphery of the housing.

[0098] refer to Figure 11 In embodiments of this disclosure, the sealing portion 800 may be configured to seal the outer periphery of the housing.

[0099] In embodiments of this disclosure, as described in the sealing portion of the welded portion, the sealing portion for sealing the outer periphery of the housing may comprise a material with high chemical resistance and sealing performance, selected from polyolefin-based resins (such as polypropylene, polyethylene, polyethylene acrylic, or polybutene), polyurethane resins, polyimide resins, or mixtures thereof. However, the material of the sealing portion is not limited to this and may include any material used as a sealant for the housing of an electrochemical device.

[0100] According to another aspect of this disclosure, methods for manufacturing electrode assemblies and electrochemical devices are provided.

[0101] A method for manufacturing an electrode assembly according to one aspect of this disclosure may include the steps of: preparing each of a first unit and a second unit; placing an insulating film between the first unit and the second unit; and electrically connecting the first unit and the second unit in series.

[0102] In embodiments of this disclosure, the step of preparing each of the first unit and the second unit may include the step of preparing each of the first single-cell and the second single-cell. Furthermore, when the first unit and the second unit comprise two or more single-cells, the method may further include the step of stacking the prepared first single-cell and the prepared second single-cell.

[0103] In embodiments of this disclosure, the steps of preparing each of the first and second single-cell cells may further include the following steps: sequentially stacking a positive electrode, a separator, and a negative electrode, and, if necessary, stacking additional separators on top and / or at the bottom, and laminating them by applying predetermined heat and / or pressure.

[0104] In embodiments of this disclosure, the step of connecting the first unit and the second unit in series may include soldering the first positive terminal piece (or the first positive terminal piece cluster) in the first unit and the second negative terminal piece (or the second negative terminal piece cluster) in the second unit, or soldering the first negative terminal piece (or the first negative terminal piece cluster) in the first unit and the second positive terminal piece (or the second positive terminal piece cluster) in the second unit.

[0105] Subsequently, if necessary, the method may also include a sealing step for the welded portion of the sealing electrode terminal.

[0106] A method for manufacturing an electrochemical device according to one aspect of this disclosure may include the following steps after manufacturing the electrode assembly as described above: forming electrode leads for each unsoldered electrode tab (or cluster of unsoldered tabs) to connect the first and second units of the electrode assembly in series.

[0107] Subsequently, the method may include the steps of placing an electrode assembly with electrode leads in a housing and injecting an electrolyte.

[0108] According to embodiments of this disclosure, the method may include a sealing step of sealing the outer periphery of a shell filled with electrolyte.

[0109] The methods described above for manufacturing electrode components and electrochemical devices are not limited thereto.

[0110] The present disclosure will be described in more detail below by way of examples, but the following examples are provided for illustrative purposes and the scope of the disclosure is not limited thereto.

[0111] Manufacturing of bag-type electrochemical devices

[0112] Comparison Example 1

[0113] An electrode assembly comprising sequentially stacked negative / separator / positive electrodes is housed in a pouch-shaped casing. Electrode leads are connected to each of the negative and positive electrode terminals, an electrolyte is supplied, and the outer periphery of the casing is sealed. In this configuration, the electrodes are prepared such that the negative electrode terminal is on one outer side of the electrode, and the positive electrode terminal is on the other outer side of the electrode.

[0114] Example 1

[0115] like Figure 8 As shown, two single-cell units are prepared, each including a stacked negative electrode / separator / positive electrode, and an insulating film (PET film) is located between the two single-cell units. In this case, the electrodes and separators are the same as those in Comparative Example 1, except that the positive electrode terminal is located at the center of the electrode in the upper single-cell unit and the negative electrode terminal is located at the center of the electrode in the lower single-cell unit.

[0116] refer to Figure 9 The positive terminal piece 121 and the negative terminal piece 211, located at the center of the electrode assembly, are welded together and sealed. Then, refer to... Figure 10 The insulating tape 700 is attached to the position where the welded part touches the inside of the housing.

[0117] Example 2

[0118] The electrochemical device is manufactured using the same method as in Example 1, except that two single-cell units are stacked on each of the top and bottom sides.

[0119] The nominal voltage (V), capacity (Ah), and energy (Wh) of the electrochemical devices prepared in Comparative Examples 1, 1, and 2 are compared and summarized below.

[0120] Table 1

[0121] As can be seen in Table 1 above, it is confirmed that as the number of individual cells (with the insulating film positioned between the individual cells) in each of the upper and lower sides increases, the nominal voltage of the electrochemical device increases by twice the number of individual cells. In this case, the capacity of the electrochemical device also increases, confirming that the energy density can be further increased.

[0122] Although this disclosure has been described above with reference to embodiments and examples, those skilled in the art will make various changes and modifications based on the foregoing without departing from the scope of this disclosure.

[0123] [List of reference numerals]

[0124] 1: Electrode assembly

[0125] 100: First single cell

[0126] 110: First negative electrode

[0127] 111: First negative terminal piece

[0128] 120: First positive electrode

[0129] 121: First positive terminal piece

[0130] 130: First separator

[0131] 1000: Unit 1

[0132] 200: Second single cell

[0133] 210: Second negative electrode

[0134] 211: Second negative terminal piece

[0135] 220: Second positive electrode

[0136] 221: Second positive terminal piece

[0137] 230: Second separator

[0138] 2000: Unit Two

[0139] 300: Insulating film

[0140] 400: Electrode lead

[0141] 410: Negative lead

[0142] 420: Positive lead

[0143] 500: Housing

[0144] 600: Welding section

[0145] 700: Insulation section

[0146] 800: Sealing part

Claims

1. An electrode assembly, comprising: The first unit includes at least one first single cell. The second unit includes at least one second single cell. as well as An insulating film, which is positioned between the first unit and the second unit, The first unit and the second unit are connected in series.

2. The electrode assembly according to claim 1, in, The first unit comprises two or more first single-cell batteries connected in parallel, and The second unit includes two or more second single-cell batteries that are connected in parallel.

3. The electrode assembly according to claim 1, in, Each electrode tab in the first and second units is located on the same shorter side of the electrode assembly.

4. The electrode assembly according to claim 1, in, The first electrode tab in the first unit and the second electrode tab in the second unit are positioned such that they overlap at least partially based on the stacking orientation of the first unit and the second unit, and The first electrode and the second electrode have different polarities.

5. The electrode assembly according to claim 1, in, The electrode assembly includes: At the welding section, the first electrode terminal piece in the first unit and the second electrode terminal piece in the second unit are welded together, and The first electrode and the second electrode have different polarities.

6. The electrode assembly according to claim 5, in, The first single cell includes a first negative electrode, a first separator, and a first positive electrode stacked in sequence. The second single-cell unit includes a second positive electrode, a second separator, and a second negative electrode stacked in sequence. The welded portion is formed in the following manner: Solder the terminal block of the first positive electrode to the terminal block of the second negative electrode, or Solder the terminal block of the first negative electrode and the terminal block of the second positive electrode.

7. The electrode assembly according to claim 5, further comprising: A sealing part, which is used to seal the welded part.

8. The electrode assembly according to claim 1, in, The electrode assembly includes an equal number of first single-cell cells and second single-cell cells.

9. The electrode assembly according to claim 1, in, The insulating film has openings for contact between the first electrode tab in the first unit and the second electrode tab in the second unit.

10. An electrochemical device, comprising: The electrode assembly according to any one of claims 1 to 9, Electrolytes, and A housing that contains the electrode assembly and the electrolyte.

11. The electrochemical device according to claim 10, in, The electrochemical device includes electrode leads connected to each electrode tab, the electrode tabs being positioned such that they do not overlap based on the stacking orientation of the first and second units.

12. The electrochemical device according to claim 10, in, The electrochemical device includes: At the welding section, the first electrode terminal piece in the first unit and the second electrode terminal piece in the second unit are welded together, and The electrochemical device further includes: An insulating portion is present at the location where the welded portion touches the inside of the housing.

13. The electrochemical device according to claim 10, further comprising: A sealing portion for sealing the outer periphery of the housing.

14. The electrochemical device according to claim 10, in, The shell is a bag-shaped shell.

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