KR101796156B1 - Cell pouch with high insulation resistance and barrier properties - Google Patents

Abstract

A cell pouch excellent in insulation resistance and barrier property is disclosed in this specification. In one aspect, the cell pouch comprises a sealant layer; An intermediate layer formed on the sealant layer; A metal layer formed on the intermediate layer; And an outer layer formed on the metal layer, wherein the intermediate layer comprises polyvinylidene chloride. In another aspect, the cell pouch comprises a sealant layer; A metal layer formed on the sealant layer; And an outer layer formed on the metal layer, wherein the sealant layer comprises a sealing resin and polyvinylidene chloride.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a cell pouch having excellent insulation resistance and barrier properties,

A cell pouch excellent in insulation resistance and barrier property is disclosed in this specification.

In general, a cell such as a secondary battery is embedded in a metal can. The metal can is mainly made of aluminum (Al), and is formed into a cylindrical shape or a square shape (such as a rectangular parallelepiped) through press working.

However, the metal can has a limit that the outer wall is rigid and the shape of the cell itself is determined by the shape of the metal can. In order to overcome such a limitation, a flexible cell pouch has been developed and used. In general, a flexible cell pouch is manufactured in a multi-layer structure in consideration of gas barrier property, electrolyte resistance and heat adhesion property.

The cell pouch generally comprises a sealant layer, a metal layer (for example, an aluminum metal layer) for gas barrier, and an outer layer (e.g., a nylon resin layer) as an outermost layer.

The sealant layer is located innermost in the cell pouch and contacts the contents, i. E. The cell. The sealant layer mainly comprises a polypropylene resin in order to stabilize the heat resistance and cold resistance of the battery. The metal layer is intended to block gas entering and out along with the mechanical strength, and an aluminum foil (Al foil) is mainly used. The outer layer is for protecting the metal layer, and polyethylene terephthalate (PET) resin and / or nylon resin is mainly used in consideration of heat resistance, pinhole resistance and abrasion resistance.

The cell pouches have a problem in stability due to the risk of being damaged by an external impact or being deformed by heat or humidity. Specifically, there is a risk that cracks may occur in the metal layer when the battery is manufactured or when an external shock is applied. In addition, physical stability such as tensile strength and bending strength is deteriorated, and there is a problem that stability at high temperature is poor, such as being easily deformed by heat, humidity, or the like. In this case, there is a danger that the electrolyte inside can leak out, and the leaked electrolyte reacts with moisture in the atmosphere to generate hydrogen which is an explosive gas. Further, due to the lowering of the insulation resistance generated at the time of heat fusion, the electrical performance is lowered when the cells are packed, resulting in lower reliability and a higher defect rate.

On the other hand, polypropylene is widely used for cell pouches because of its excellent mechanical properties such as tensile strength, rigidity, surface hardness and impact resistance, optical properties such as gloss and transparency, etc. However, when a battery is assembled and driven, AL layer is reached and the insulation resistance is lowered.

Korean Patent Registration No. 10-1307068

In one aspect, the present invention aims to provide a cell pouch in which polyvinylidene chloride is coated or added to an inner layer of a metal layer to increase gas barrier property, insulation resistance and barrier property.

In one aspect, the technique disclosed herein includes a sealant layer; An intermediate layer formed on the sealant layer; A metal layer formed on the intermediate layer; And an outer layer formed on the metal layer, wherein the intermediate layer comprises polyvinylidene chloride, and has excellent insulation resistance and barrier properties.

In an exemplary embodiment, the intermediate layer may be an adhesive resin layer comprising an adhesive resin and polyvinylidene chloride.

In one exemplary embodiment, the intermediate layer comprises an adhesive resin layer comprising an adhesive resin and polyvinylidene chloride and formed on the sealant layer; And a polyvinylidene chloride layer formed on the adhesive resin layer.

In an exemplary embodiment, the intermediate layer comprises an adhesive resin layer comprising an adhesive resin and formed on the sealant layer; And a polyvinylidene chloride layer formed on the adhesive resin layer.

In an exemplary embodiment, the adhesive resin may be at least one selected from the group consisting of an epoxy resin, a urethane resin, an acrylic resin, an olefin resin, and a nylon resin.

In an exemplary embodiment, the adhesive resin may be at least one melt-extruded resin selected from the group consisting of a polypropylene resin and a polyethylene resin.

In an exemplary embodiment, the polyvinylidene chloride may be mixed in an amount of 1 to 40% by weight based on the total weight of the composition of the adhesive resin layer.

In an exemplary embodiment, the polyvinylidene chloride layer may comprise from 1 to 20% of the total thickness of the cell pouch.

In an exemplary embodiment, the sealant layer may be one comprising a sealing resin and polyvinylidene chloride.

In an exemplary embodiment, the sealant layer comprises a first skin layer comprising a sealing resin and polyvinylidene chloride and in contact with the intermediate layer; A main layer including a sealing resin and formed on the first skin layer; And a second skin layer including a sealing resin and formed on the main layer.

In an exemplary embodiment, the sealing resin may be a polypropylene resin.

In an exemplary embodiment, the polyvinylidene chloride may be mixed in an amount of 1 to 40% by weight based on the total weight of the composition of the first skin layer.

In another aspect, the technique disclosed herein includes a sealant layer; A metal layer formed on the sealant layer; And an outer layer formed on the metal layer, wherein the sealant layer comprises a sealing resin and polyvinylidene chloride, and has excellent insulation resistance and barrier properties.

In an exemplary embodiment, the sealant layer comprises a first skin layer comprising a sealing resin and polyvinylidene chloride and in contact with the metal layer; A main layer including a sealing resin and formed on the first skin layer; And a second skin layer including a sealing resin and formed on the main layer.

In an exemplary embodiment, the sealing resin may be a polypropylene resin.

In an exemplary embodiment, the polyvinylidene chloride may be mixed in an amount of 1 to 40% by weight based on the total weight of the composition of the first skin layer.

In another aspect, the technique disclosed herein provides a secondary battery including the cell pouch.

In one aspect, the technique disclosed herein has the effect of providing a cell pouch with increased gas barrier properties, insulation resistance, and barrier properties by coating or adding polyvinylidene chloride to the inner layer of the metal layer.

1 is a schematic cross-sectional view of a cell pouch according to an embodiment of the present invention.
2 shows a cross-sectional structure of a cell pouch according to one comparative example of the present specification.
3 illustrates a cross-sectional structure of a cell pouch according to an embodiment of the present invention.
4 illustrates a cross-sectional structure of a cell pouch according to an embodiment of the present invention.
5 illustrates a cross-sectional structure of a cell pouch according to an embodiment of the present invention.
6 illustrates a cross-sectional structure of a cell pouch according to an embodiment of the present invention.
7 illustrates a cross-sectional structure of a cell pouch according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail.

As used herein, the term "cell " refers to a battery, and includes all kinds of batteries such as a secondary battery such as a lithium ion battery, a lithium polymer battery, and a portable battery.

In the present specification, the term "cell pouch" refers to a cell in which a cell component such as an anode, a cathode, and a separator is impregnated and impregnated with an electrolytic solution. In order to accommodate the cell component, The film having the laminated structure in consideration of the heat resistance, the heat resistance, the heat resistance, the heat resistance,

The cell pouch according to one embodiment of the present disclosure includes a sequentially stacked sealant layer; A metal layer; And at least three layers including an outer layer. The cell pouch according to another embodiment of the present disclosure includes a sequentially stacked sealant layer; Intermediate layer; A metal layer; And an outer layer. Between each layer of the cell pouch, a layer structure, a component, and the like that are commonly used for adhesion, heat resistance, cold resistance, corrosion resistance, insulation, and / or moldability can be appropriately employed.

1 is a schematic cross-sectional view of a cell pouch according to an embodiment of the present invention. The cell pouch comprises a sealant layer (1); An intermediate layer (2) formed on the sealant layer (1); A metal layer (3) formed on the intermediate layer (2); And an outer layer 4 formed on the metal layer 3. According to a specific embodiment of the present invention, the cell pouch may be formed by omitting the intermediate layer 2. [

The sealant layer 1 may be a seal resin for heat adhesion, which is formed by holding (embedding) a cell and then adhering (thermally fusing) by heat to impart sealability. Since the sealant layer is in contact with the cell component, the sealant layer can be constructed by suitably employing a layer structure commonly used for imparting insulating properties, electrolyte resistance, and / or high heat bonding strength (sealability).

The sealing resin is not limited as long as it can be fused (thermally adhered) by heat, and it may preferably be a resin having heat resistance, insulation property, electrolyte resistance and / or cold resistance. The sealing resin can be preferably selected from low melting point resins which can be thermally fused at low temperatures.

In an exemplary embodiment, the sealing resin may be selected from, but not limited to, polyolefins such as polypropylene (PP) or polyethylene (PE), copolymers or derivatives thereof, and ethylene vinyl acetate Can be used. The sealing resin may also be selected from co-polymers or ter-polymers, such as ethylene / propylene copolymers or terpolymers of ethylene / propylene / butadiene (terpolymers) have.

In an exemplary embodiment, the sealing resin may be polypropylene (PP) based. The sealing resin may be at least one polypropylene (PP) system selected from homopolymer (homo-PP), polypropylene copolymer (PP co-polymer) and polypropylene terpolymer Or polyethylene (PE) or ethylene vinyl acetate (EVA) may be mixed with the polypropylene (PP) system. The polypropylene (PP) based resin is excellent in thermal adhesiveness (sealability) and insulation, and is also excellent in mechanical properties such as tensile strength, rigidity and surface hardness, chemical resistance such as electrolyte resistance, It is excellent in compatibility and can be used effectively.

In an exemplary embodiment, the sealant layer may further include polyvinyl chloride (PVDC) (PVDC) together with a sealing resin to increase insulation resistance and barrier properties. When the sealant layer is composed of polyvinylidene chloride alone, it is preferable that the seal pouch is used together with a sealing resin, specifically, a polypropylene resin having excellent thermal adhesiveness because the cell pouch is not thermally adhered. In order to increase the mixing and kneading property with the sealing resin, polyvinylidene chloride is preferably first formed into a mixed resin and then a sealant layer is formed.

In an exemplary embodiment, the sealant layer comprises a first skin layer comprising a sealing resin and polyvinylidene chloride and in contact with a metal layer or intermediate layer; A main layer including a sealing resin and formed on the first skin layer; And a second skin layer including a sealing resin and formed on the main layer. At this time, the sealant layer may be formed by simultaneously extruding the first skin layer, the main layer, and the second skin layer through an extruder while the three layers are combined in an extrusion die. A resin layer for thermal lamination, i.e., thermal fusion bonding, may be laminated on the first skin layer.

In an exemplary embodiment, the polyvinylidene chloride is present in an amount of 1 to 40%, 1 to 30%, 1 to 20%, 1 to 15%, or 1% by weight, based on the total weight of the composition of the first skin layer. To 10% by weight. Thereby, there is an effect that it is possible to prevent a problem of delamination which may occur due to a problem of kneading property with a sealing resin, and to increase insulation resistance and barrier property.

The thickness of the sealant layer is not particularly limited, but may be, for example, 5 占 퐉 to 150 占 퐉, 10 占 퐉 to 100 占 퐉, or 10 占 퐉 to 80 占 퐉. The sealant layer may preferably have a thickness of 20 占 퐉 or more, specifically 20 占 퐉 to 70 占 퐉, and more preferably 30 占 퐉 to 60 占 퐉, for good heat-seal strength (sealability).

The intermediate layer 2 includes polyvinylidene chloride (PVDC) and is formed between the sealant layer and the metal layer to significantly increase gas barrier properties, insulation resistance and barrier properties of the cell pouch. It is preferable that the technique disclosed in this specification is used together with an adhesive resin in order to prevent the adhesion and the thermal adhesiveness with the metal layer from being decreased due to the coating or addition of polyvinylidene chloride. The specific lamination structure of the intermediate layer for increasing the gas barrier property, insulation resistance and barrier property of the cell pouch is as follows.

In an exemplary embodiment, the intermediate layer may be an adhesive resin layer comprising an adhesive resin and polyvinylidene chloride.

In one exemplary embodiment, the intermediate layer comprises an adhesive resin layer comprising an adhesive resin and polyvinylidene chloride and formed on the sealant layer; And a polyvinylidene chloride layer formed on the adhesive resin layer.

In an exemplary embodiment, the intermediate layer comprises an adhesive resin layer comprising an adhesive resin and formed on the sealant layer; And a polyvinylidene chloride layer formed on the adhesive resin layer.

In an exemplary embodiment, the adhesive resin layer serves to bond the two layers by applying an adhesive force between the upper and lower two layers, and the adhesive resin is not limited as long as the adhesive can adhere the layer For example, an epoxy resin such as an epoxy resin or a modified epoxy resin; Urethane resins such as urethane resin and modified urethane resin; Acrylic resin such as acrylic resin or modified acrylic resin; Olefin resins such as polyethylene (PE) and polypropylene (PP), olefin resins such as modified olefin resins thereof; And nylon resin, and the like.

In an exemplary embodiment, the adhesive resin layer may be a melt extruded resin layer formed by melt extrusion of a resin, and the adhesive resin may be a polypropylene resin and a polyethylene resin Is preferably at least one melt-extruded resin selected from the group consisting of

In an exemplary embodiment, the polyvinylidene chloride is present in the adhesive resin layer in an amount of from 1 to 40% by weight, from 1 to 30% by weight, from 1 to 20% by weight, from 1 to 15% by weight, 10% by weight. Thereby, there is an effect that it is possible to prevent a problem of delamination which may occur due to a problem of kneading property with an adhesive resin, and to increase insulation resistance and barrier property.

In an exemplary embodiment, the polyvinylidene chloride layer may be formed by a method of laminating a PVDC film or coating a PVDC, wherein the polyvinylidene chloride layer is applied to the cell pouch in an amount of 1 to 20% 10%, or 3 to 10%. Thereby, there is an effect that the insulation resistance and the barrier property can be greatly improved while preventing delamination and quality deterioration.

In an exemplary embodiment, the intermediate layer may have a thickness of 1 [mu] m to 20 [mu] m. The intermediate layer may have a thickness of 5 占 퐉 to 20 占 퐉, 10 占 퐉 to 20 占 퐉, 2 占 퐉 to 10 占 퐉, 2 占 퐉 to 8 占 퐉, or 2 占 퐉 to 6 占 퐉 in order to improve gas barrier properties, insulation resistance and barrier properties .

The metal layer 3 is not limited as long as it is a metal having gas barrier properties. The metal layer can block moisture from outside, air, and gas generated from the inside.

In an exemplary embodiment, the metal layer may include at least one selected from metal thin films, metal deposition layers, and the like. The metal thin film may be a metal foil or the like and the metal vapor deposition layer may be a separate plastic film such as polyethylene terephthalate (PET), polyethylene (PE), or polypropylene (PP) Or may be formed by vacuum deposition on a film.

For example, a metal such as aluminum (Al), iron (Fe), copper (Cu), nickel (Ni) or the like may be used as the metal constituting the metal layer, (A single metal or a mixture of single metals) selected from the group consisting of tin (Sn), zinc (Zn), indium (In) and tungsten (W) ), And the like. And may preferably be selected from aluminum (Al) or an aluminum alloy (Al alloy). In addition, the metal layer may be subjected to surface treatment with phosphoric acid, chromium, or the like or micro-irregularity treatment for corrosion resistance.

In an exemplary embodiment, the metal layer may have a thickness of 1 탆 to 60 탆, 5 탆 to 50 탆, 10 탆 to 40 탆, or 10 탆 to 30 탆.

The outer layer 4 protects the metal layer and is excellent in wear resistance, for example, heat resistance, cold resistance, pinhole resistance, insulation, solvent resistance, and / or moldability (when a flexible cell pouch is processed into a predetermined shape Shape-retaining property), and the like can be appropriately employed in the layer structure.

In an exemplary embodiment, the outer layer may comprise one or more resins selected from nylon resin, polyethylene terephthalate (PET) resin, and polyolefin-based resin. Examples of the polyolefin-based resin include polyethylene (PE) and polypropylene (PP). The outer layer may preferably comprise a nylon resin. For example, the outer layer may be composed of a nylon resin layer, a polyethylene terephthalate (PET) layer, or a composite layer thereof.

In an exemplary embodiment, the thickness of the outer layer is not particularly limited, but may be, for example, 10 占 퐉 to 50 占 퐉, preferably 5 占 퐉 to 30 占 퐉, more preferably 10 占 퐉 to 25 占 퐉 Lt; / RTI >

Meanwhile, the cell pouch according to the present invention has a multilayer structure as described above, and the manufacturing method thereof is not limited, and can be manufactured, for example, by co-extrusion or lamination. In an exemplary embodiment, the sealant layer can be co-extruded on the metal layer. The outer layer and the intermediate layer may be coextruded on the metal layer. At this time, when co-extruded, it may be co-extruded at a temperature of 400 DEG C or less, though not particularly limited thereto. Specific examples thereof may be co-extruded at a temperature of from 150 to 400 ° C, more specifically from 200 to 350 ° C.

Further, at least one selected from the sealant layer, the intermediate layer and the outer layer may further contain additives in addition to the base resin (main component) constituting the sealant layer, the intermediate layer and the outer layer. The additive includes at least one selected from an antifogging agent, a slip agent, and an anti-blocking agent, and the kind of the additive is not limited thereto. In an exemplary embodiment, the additive may be included, for example, in an amount of 0.01 to 20 parts by weight, more specifically 0.05 to 10 parts by weight, based on 100 parts by weight of the base resin constituting each layer.

The cell pouch disclosed in this specification is excellent in strength, resistance, durability, water vapor and other gas barrier properties of cell pouches, heat bonding, heat adhesion to electrode terminals, etc., and physical force acts on electrode terminals and pouches (Outer packaging material) which is excellent in stability without causing a short circuit in the pouch (outer packaging material).

Hereinafter, the present invention will be described in more detail with reference to Examples. It is to be understood by those skilled in the art that these embodiments are merely illustrative of the present invention and that the scope of the present invention is not construed as being limited by these embodiments.

Comparative Example 1

An aluminum (Al) thin film having a thickness of 40 탆 was prepared as a metal layer, and the outer surface of the aluminum thin film was coated with a nylon resin to have a thickness of 25 탆. Thereafter, an intermediate layer composed of a polypropylene resin and an extruded resin layer (adhesive resin layer) was formed on the other surface of the aluminum (Al) thin film through a polypropylene melt extruded resin, and the sealant layer was formed to have a thickness of 50 占 퐉 at 300 占 폚 . That is, a cell pouch having a flat shape without forming the sealant layer / intermediate layer / metal layer / outer layer laminate structure (see Fig. 2) was manufactured. Then, an electrode group was inserted into the cell pouch to prepare a secondary battery.

Example 1.

A cell pouch was prepared in the same manner as in Comparative Example 1 except that an intermediate layer (see FIG. 3) composed of an extruded resin layer mixed with 15% by weight of PVDC together with a polypropylene resin was formed by a co-extrusion method.

Example 2.

A cell pouch was prepared in the same manner as in Comparative Example 1 except that an aluminum (Al) thin film was coated with PVDC at 2 to 3 탆 on one side to form an intermediate layer (see FIG. 4) composed of a PVDC coating layer and a polypropylene extrusion resin layer .

Example 3.

PVDC was coated on one side of the aluminum (Al) thin film in the same manner as in Comparative Example 1, except that 15 wt% of PVDC was blended with the polypropylene resin by a co-extrusion method An extruded resin layer was formed to form an intermediate layer (see Fig. 5) composed of a PVDC coating layer and a polypropylene + PVDC extruded resin layer.

Example 4.

A cell pouch was prepared in the same manner as in Comparative Example 1 except that a first skin layer mixed with 15 wt% PVDC together with a polypropylene resin, a main layer formed on the first skin layer, and a second skin layer formed on the main skin layer A seal pouch composed of a skin layer was laminated to prepare a cell pouch (see Fig. 6). The first skin layer was formed to a thickness of 10 mu m.

Example 5.

A cell pouch was prepared in the same manner as in Comparative Example 1 except that a PVDC coating layer was formed by coating PVDC with 2 to 3 占 퐉 on one side of an aluminum (Al) thin film, and 15% by weight of PVDC mixed with polypropylene resin A cell pouch (see FIG. 7) was prepared by laminating a sealant layer composed of a first skin layer, a main layer formed on the first skin layer, and a second skin layer formed on the main layer, 10 mu m.

Experimental Example 1

Using the respective specimens prepared in Comparative Example 1 and Examples 1 to 5, cell pouches (outer sheath) of 30 mm x 40 mm x 6 mm deep were formed. A dummy cell was fabricated by injecting a standard electrolyte (EC: DEC: EMC = 1: 1: 1, LiPF6 1M) while sealing the cell pouch. Punching a certain part of the prepared cell, And the resistance value was measured by applying a voltage of 25 V to the punched region and the tab region of the substrate. Each evaluation was measured at 10EA. After the 2nd test, the bending part of each wing (sealing part) was folded once and then the insulation resistance value was measured. When the resistance value is more than 200MΩ (∞ for 200MΩ or more), it means good product.

Insulation resistance test result Insulation Resistance
(MΩ) Comparative Example 1 Example 1 Example 2 Example 3 Example 4 Example 5 Primary ∞ ∞ ∞ ∞ ∞ ∞ Secondary ∞ ∞ ∞ ∞ ∞ ∞ Third ∞ ∞ ∞ ∞ ∞ ∞ Fourth ∞ ∞ ∞ ∞ ∞ ∞ 5th 102 ∞ ∞ ∞ ∞ ∞ 6th - ∞ ∞ ∞ ∞ ∞ Seventh - ∞ ∞ ∞ ∞ ∞ 8th car - ∞ 118 ∞ ∞ ∞ 9th - ∞ - ∞ 91 ∞ Ten cars ∞ - ∞ - ∞ 11th car 49 - ∞ - ∞ 12 cars - ∞ - ∞ 13th car - - - ∞ - 123 14th - - - ∞ - - 15 cars - - - ∞ - - 16th - - - 156 - -

As a result, it was confirmed that the insulation resistance of Examples 1 to 5 containing polyvinylidene chloride in the intermediate layer or the sealant layer was superior to Comparative Example 1 in which polyvinylidene chloride was not contained in the intermediate layer or the sealant layer. In particular, the insulation resistance of Example 3 including a PVDC coating layer and an intermediate layer composed of a polypropylene + PVDC extruded resin layer was remarkably high.

Having described specific portions of the present invention in detail, it will be apparent to those skilled in the art that this specific description is only a preferred embodiment and that the scope of the present invention is not limited thereby. It will be obvious. Accordingly, the actual scope of the present invention will be defined by the appended claims and their equivalents.

1: sealant layer 2: middle layer
3: metal layer 4: outer layer

Claims (16)

A sealant layer;
An intermediate layer formed on the sealant layer;
A metal layer formed on the intermediate layer; And
And an outer layer formed on the metal layer,
Wherein the intermediate layer comprises: an adhesive resin layer comprising an adhesive resin and polyvinylidene chloride and formed on the sealant layer; And a polyvinylidene chloride layer formed on the adhesive resin layer, wherein the polyvinylidene chloride layer has excellent insulation resistance and barrier properties.
delete delete delete The method according to claim 1,
Wherein the adhesive resin is at least one selected from the group consisting of an epoxy resin, a urethane resin, an acrylic resin, an olefin resin and a nylon resin.
6. The method of claim 5,
Wherein the adhesive resin is at least one melt-extruded resin selected from the group consisting of a polypropylene resin and a polyethylene resin, and has excellent insulation resistance and barrier properties.
The method according to claim 1,
The polyvinylidene chloride is mixed with 1 to 40% by weight based on the total weight of the composition of the adhesive resin layer, and has excellent insulation resistance and barrier properties.
The method according to claim 1,
Wherein the polyvinylidene chloride layer accounts for 1 to 20% of the total thickness of the cell pouch, and has excellent insulation resistance and barrier properties.
The method according to claim 1,
Wherein the sealant layer comprises a sealing resin and polyvinylidene chloride, and has excellent insulation resistance and barrier properties.
10. The method of claim 9,
Wherein the sealant layer comprises: a first skin layer comprising a sealing resin and polyvinylidene chloride and in contact with the intermediate layer; A main layer including a sealing resin and formed on the first skin layer; And a second skin layer containing a sealing resin and formed on the main layer, the cell pouch having excellent insulation resistance and barrier properties.
11. The method of claim 10,
Wherein the sealing resin is a polypropylene resin and has excellent insulation resistance and barrier properties.
11. The method of claim 10,
Wherein the polyvinylidene chloride is mixed in an amount of 1 to 40% by weight based on the total weight of the composition of the first skin layer, and has excellent insulation resistance and barrier properties.
delete delete delete delete

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