KR102348930B1 - Electrode struscture and electrochemical device using the same - Google Patents

Abstract

The electrode structure of the electrochemical device according to the embodiment is an electrode structure comprising a base substrate and an electrode composition layer disposed on the base substrate, wherein the electrode composition layer is a base material and a conductive material disposed on the base material Including a material, the density of the base material in the electrode composition layer may be higher than the density of the conductive material.

Description

Electrode structure and electrochemical device including the same

The embodiment relates to an electrode structure and an electrochemical device including the same.

Recently, interest in energy storage technology is increasing.

Efforts for research and development of electrochemical devices are becoming more and more concrete as the field of application is expanded to the energy of mobile phones, camcorders, notebook PCs, and even electric vehicles.

Electrochemical devices are attracting attention in terms of being able to charge and discharge and have high energy density, and high capacitance and energy density are required according to the expansion of application fields.

An electrochemical device enables conversion between electrical energy and chemical energy, and specific examples thereof include a super capacitor, a lithium ion secondary battery, a hybrid capacitor, and the like.

Supercapacitors are electric double layer capacitors that accumulate electricity through electrostatic adsorption and desorption of ions, pseudo capacitors that accumulate electricity through oxidation-reduction reactions, and asymmetric electrode shapes. Branches can be divided into hybrid capacitors.

An electric double-layer supercapacitor consists of a unit cell including an anode and a cathode impregnated in an electrolyte, a separator provided between the two electrodes, a gasket for preventing electrolyte leakage and insulation and short-circuit prevention, a metal case, etc., such a unit cell is laminated and the terminals of the positive electrode and the negative electrode are combined, and the composition for forming an electrode may include a binder and a conductive material in addition to the electrode active material, and each component may be applied to the supercapacitor in the form of a slurry after mixing.

Such supercapacitors can be used for regenerative braking components that require high output that are difficult to respond to with conventional batteries, or for memory protection functions to prepare for momentary power failure.

For example, unlike a battery that uses a chemical reaction, a supercapacitor uses the movement of ions to the electrode and electrolyte interface or a charging phenomenon by a surface chemical reaction. Accordingly, rapid charge/discharge is possible, and due to high charge/discharge efficiency and semi-permanent cycle life characteristics, it is in the spotlight as a next-generation energy storage device that can be used as a substitute for an auxiliary battery or a battery.

On the other hand, the secondary battery has the advantage of high energy density, but has the disadvantage of low charging speed, whereas the super capacitor has the advantage of high output density and high charging speed, but has the disadvantage of low energy density.

The low energy density of such a supercapacitor is a disadvantage in that it is inferior to a secondary battery or a lead-acid battery as an energy storage device.

Accordingly, the technology development of the prior art supercapacitor is progressing in the direction to increase the low energy density, which is a technical disadvantage. For example, an electrolyte solution that can be used at high voltage or increase the specific surface area of activated carbon in the electrode part is being developed.

On the other hand, since the energy density (E), which is the total amount of energy that can be charged with the supercapacitor, is proportional to the capacitance (C), it is necessary to make an effort to improve the energy density (E) by increasing the capacitance (C), but appropriate technology It is a situation where no solution can be found.

1 is a cross-sectional photograph of an electrode structure of an electrochemical device according to the prior art.

In the prior art, the internal structure of an electrochemical device, for example, a supercapacitor is shown in FIG. 1 . Specifically, porous activated carbons (A) with conductive materials (Conductive aids) form a kind of bridge (Bridge), and consists of binders (Binders) supporting this structure.

On the other hand, activated carbon (A) mainly acts on the adsorption of ions, which influences the performance of the supercapacitor. In this case, there is a technical problem in that the binder or the conductive material may act as a factor that interferes with this role of the activated carbon.

That is, when the binder or the conductive material is present more than necessary, the ratio of the activated carbon is lowered, and there is a problem in that the ion adsorption power of the activated carbon is lowered, thereby lowering the capacitance.

In addition, if the conductive material is not uniformly disposed on the surface of the activated carbon, there is a problem in that the impedance (impedance) between the electrode and the electrolyte increases and the capacitance is lowered.

The embodiment is intended to provide an electrode structure capable of improving the energy density (E) by increasing the capacitance (C) and an electrochemical device including the same.

Another object of the embodiment is to provide an electrode structure with improved electrical properties and an electrochemical device including the same.

For example, the embodiment provides an electrode structure capable of solving the problem of unnecessarily the presence of a binder or a conductive material and, as the ratio of activated carbon is lowered, the ion adsorption power of activated carbon is lowered and the capacitance is lowered, and an electrochemical device including the same. want to

In addition, the embodiment provides an electrode structure capable of solving the problem of a decrease in capacitance due to a decrease in electrical characteristics due to an increase in impedance between an electrode and an electrolyte as the conductive material is not uniformly disposed on the surface of the activated carbon, and an electrode structure including the same To provide a chemical device.

The technical problems to be solved in the embodiments are not limited to those described in this item, and may be understood through the entire description of the invention.

The electrode structure of the electrochemical device according to the embodiment is an electrode structure comprising a base substrate and an electrode composition layer disposed on the base substrate, wherein the electrode composition layer is a base material and a conductive material disposed on the base material Including a material, the density of the base material in the electrode composition layer may be higher than the density of the conductive material.

In an embodiment, the tap density of the base material in the electrode composition layer may be 5 times or more of the tap density of the conductive material.

In addition, the base material may have a tap density ratio of 5 to 7 times that of the conductive material.

In addition, the base material in the electrode composition layer may have a mass ratio of 35 to 40 times that of the conductive material.

In an embodiment, the electrode composition layer further includes a binder in addition to the base material and the conductive material, and the mass ratio in the electrode composition layer is, base material: conductive material: binder = 93 to 97: 2 to 3.5: 2 to 3.5 can be

In an embodiment, the electrode composition layer further includes a binder in addition to the base material and the conductive material, and the volume ratio based on the tap density in the electrode composition layer is, base material: conductive material: binder = 83-87: 12- 15: It may be 1.0-2.0.

In addition, the density of the base material in the electrode composition layer may be 0.75 (g/cc) or more.

In addition, the density occupied by the base material in the electrode composition layer may be 0.758 (g/cc) to 0.772 (g/cc). In addition, the electrochemical device according to the embodiment may include the electrode structure.

The embodiment has a technical effect that can provide an electrode structure capable of improving the energy density (E) by increasing the capacitance (C) and an electrochemical device including the same.

For example, in the embodiment, since the amount of unnecessary binder and conductive material between the activated carbon and the activated carbon is minimized, as the ratio of the activated carbon increases, the ion adsorption power of the activated carbon is improved and the electrostatic capacity is increased. It is possible to provide an electrochemical device that

Another object of the embodiment is to provide an electrode structure with improved electrical properties and an electrochemical device including the same.

For example, in the embodiment, as the conductive material is uniformly disposed on the surface of the activated carbon, the impedance (impedance) between the electrode and the electrolyte is lowered, so that the electrode structure having the technical effect of increasing the capacitance according to the improvement of the electrical properties and the electrochemical including the same devices can be provided.

The technical effect of the embodiment is not limited to that described in this item, and can be grasped through the entire description of the name.

1 is a cross-sectional photograph of an electrode structure of an electrochemical device according to the prior art.
2 is a schematic diagram of an electrochemical device according to an embodiment;
3 is a cross-sectional view of an electrochemical device according to an embodiment.
Figure 4a is a conceptual diagram of a composition layer for an electrode in the electrode structure of the electrochemical device according to the embodiment.
Figure 4b is a photograph of a composition layer for an electrode in the electrode structure of the electrochemical device according to the embodiment.
Figure 4c is an enlarged conceptual view of a composition layer for an electrode in the electrode structure of the electrochemical device according to the embodiment.
5 is a conceptual diagram of a manufacturing process of a composition layer for an electrode in an electrode structure of an electrochemical device according to an embodiment.
6 is a CV data of the electrochemical device according to the embodiment and the prior art.
7 is an electrochemical impedance analysis (EIS) data of the electrochemical device according to the embodiment and the prior art.
Fig. 8 is capacitance data of an electrochemical device according to the embodiment and the prior art.

Hereinafter, embodiments that can be specifically realized for solving the above problems will be described with reference to the accompanying drawings.

In the description of the embodiment, in the case where it is described as being formed on "on or under" of each element, the upper (upper) or lower (on or under) is The two elements are in direct contact with each other or one or more other elements are disposed between the two elements indirectly. In addition, when expressed as "up (up) or down (on or under)", it may include the meaning of not only an upward direction but also a downward direction based on one element.

(Example)

Figure 2 is a schematic view of the electrochemical device 100 according to the embodiment, Figure 3 is a cross-sectional view of the electrochemical device according to the embodiment.

The electrochemical device of the embodiment is not particularly limited as long as it is within a range that does not deviate from the purpose of the embodiment as an interconversion of electrical energy and chemical energy is possible. For example, the electrochemical device of the embodiment may be a supercapacitor, a secondary battery, etc. Hereinafter, a supercapacitor as an electrochemical device will be described as an example, but the embodiment is not limited thereto.

The electrochemical device 100 of the embodiment includes a first electrode 110 , a second electrode 120 , separators 130 and 135 , an electrolyte, a first lead wire 151 , a second lead wire 152 , and a cover 140 . It may include at least one or more of

Referring to FIG. 3 , the electrochemical device 100 according to the embodiment has a composition layer for a first electrode, which is a composition layer for electrode electrodes, on the first base substrate 110a and the second base substrate 120a, respectively. 110b) and the second electrode composition layer 120b formed by coating the first electrode 110 and the second electrode 120 may be coupled with a predetermined separator 130 interposed therebetween. The first electrode 110 may be an anode, and the second electrode 120 may be a cathode, but is not limited thereto. The second electrode composition layer 120b may be disposed under the second base substrate 120a.

Referring back to FIG. 2 , the electrode structure including the first electrode 110 / separator 130 / second electrode 120 is accommodated in a predetermined cover 140 , and then a predetermined electrolyte is injected thereto. can do it The first electrode 110 and the second electrode 120 may be electrically connected to the first lead wire 151 and the second lead wire 152 , respectively.

In the electrochemical device 100 of the embodiment, the first base substrate 110a connected to both ends of the first electrode 110 and the second electrode 120 through the first lead wire 151 and the second lead wire 152, and When a voltage of several volts is applied to the second base substrate 120a, an electric field is formed, and accordingly, ions in the electrolyte move and are adsorbed to the surfaces of the first and second electrodes 110 and 120 to store electricity. Electricity can be charged by the principle of

Next, referring to FIG. 3 , in the embodiment, at least one of the first electrode 110 and the second electrode 120 is a composition layer for the first and second electrodes on the first and second base substrates 110a and 120a. (110b, 120b) are respectively arranged.

For example, at least one of the first electrode 110 and the second electrode 120 may be a composition for forming an electrode rolled on the first and second base substrates 110a and 120a by rolling, but the present invention is limited thereto. it is not going to be

In addition, the first electrode 110 and/or the second electrode 120 may be coated with a composition for forming an electrode on the first and second base substrates 110a and 120a. In addition, the first electrode 110 and/or the second electrode 120 may be formed by forming a composition for forming an electrode in a sheet state, attaching it to the first and second base substrates 110a and 120a, and drying the composition. .

The first and second base substrates 110a and 120a may include a conductive material to improve electrical conductivity. For example, the first and second base substrates 110a and 120a may include a metal such as copper or aluminum.

4A is a conceptual diagram of a composition layer for an electrode in an electrode structure of an electrochemical device according to an embodiment, and FIG. 4B is a photograph of a composition layer for an electrode in an electrode structure of an electrochemical device according to an embodiment.

For example, in the embodiment, the first and second electrode composition layers 110b and 120b may include one or more of a base material, a binder, and a conductive material as a composition for forming an electrode, and optionally further include a solvent. can In addition, each component may be applied to the electrochemical device 100 in the form of a slurry after mixing. The first and second electrode composition layers 110b and 120b may function as active materials for the first and second electrodes 110 and 120 .

For example, the second electrode composition layer 120b may include a second base material 120b1 , a second conductive material 120b2 , and a second binder (not shown). In addition, the first electrode composition layer 110b may include a first base material (not shown), a first conductive material (not shown), and a first binder (not shown).

Hereinafter, the second base material 120b1, the second conductive material 120b2, and the second binder (not shown) for the second electrode composition layer 120b will be mainly described, but these technical features are the first electrode composition layer (110b) can be applied.

Referring to FIG. 4A , in the embodiment, the second base material 120b1 may be a predetermined carbon source. For example, the second base material 120b1 may be selected from among porous activated carbon, carbononion, carbon nanotube, graphene, carbide derived carbon, and mesoporous carbon. It may contain any one or more carbon sources.

The carbon source may include a crystalline structure (not shown) and an amorphous structure (not shown). In addition, the amorphous structure may include a plurality of pores, and since electrolyte ions are easily introduced into the pores, the electrostatic capacity may be improved, and thus the output density may be increased.

In an embodiment, the second conductive material 120b2 may impart conductivity to the composition for forming an electrode. Examples of the second conductive material 120b2 may be carbon black, graphene, carbon nanotube (CNT), carbon nanofiber (CNF), or the like, but is not limited thereto.

In an embodiment, the second binder (not shown) may impart adhesion to the composition for forming an electrode. Examples of the binder include carboxymethyl cellulose (CMC), polyvinylpyrrolidone (PVP), styrene-butadiene rubber (SBR), polyvinylidene fluoride (PVDF), polyethylene (PE), polypropylene (PP) and poly It may be vinyl alcohol (PVA), but is not limited thereto.

In an embodiment, the composition for forming an electrode may further include a solvent. For example, in the embodiment, the composition for forming an electrode may include a solvent such as water or an organic solvent, but is not limited thereto.

One of the technical problems of the embodiment is to provide an electrode structure capable of improving the energy density (E) by increasing the capacitance (C) and an electrochemical device including the same. For example, the embodiment provides an electrode structure capable of solving the problem of unnecessarily the presence of a binder or a conductive material and, as the ratio of activated carbon is lowered, the ion adsorption power of activated carbon is lowered and the capacitance is lowered, and an electrochemical device including the same. want to

In addition, one of the technical problems of the embodiment is to provide an electrode structure with improved electrical properties and an electrochemical device including the same. For example, the embodiment provides an electrode structure capable of solving the problem of a decrease in capacitance due to a decrease in electrical characteristics due to an increase in impedance between the electrode and the electrolyte as the conductive material is not uniformly disposed on the surface of the activated carbon, and An object of the present invention is to provide an electrochemical device comprising

In order to solve this technical problem, the electrochemical device 100 according to the embodiment includes the base substrates 110a and 120a and the electrode composition layers 110b and 120b disposed on the base substrates 110a and 120a. It may have an electrode structure comprising: the composition layer for the electrode includes a base material and a conductive material disposed on the base material, and the density of the base material in the composition layer for the electrode may be higher than the density of the conductive material .

4C is an enlarged conceptual diagram of a composition layer for an electrode in an electrode structure of an electrochemical device according to an embodiment.

In the electrode structure of the electrochemical device according to the embodiment, the size of the second base material 120b1 in the electrode composition layer is about 10 μm based on D(5,0), and the size of the second conductive material 120b2 is D(5, 0) It may be about 40 nm as a reference.

At this time, assuming that the second base material 120b1 and the second conductive material 120b2 are one layer to form an ideal core-shell structure, the radius of the second base material 120b1 is as shown in FIG. 4C . (R) and the angle Θ of the hypotenuse of the right triangle corresponding to the base by the radius r of the second conductive material 120b2 may be obtained.

For example, if the angle Θ of the hypotenuse is about 0.23°, assuming that the second conductive material 120b2 uniformly covers the second base material 120b1 having a diameter of about 250 times difference, approximately 2.45 million pieces are required. can

According to the embodiment, since the amount of unnecessary binder and conductive material between the activated carbon and the active carbon, which is the base material, is minimized, as the ratio of the activated carbon as the base material increases, the ion adsorption power of the activated carbon is improved to increase the electrostatic capacity of the electrode structure and An electrochemical device including the same may be provided.

5 is a conceptual diagram of a manufacturing process of a composition layer for an electrode in an electrode structure of an electrochemical device according to an embodiment.

In the embodiment, in order to form a composition layer for an electrode, the second base material 120b1, activated carbon and the second conductive material 120b2, are dispersed in a high-speed airflow, and the impact force is used as the main force to form a dry state host (host). ) The second base material 120b1, which is the particle surface, is used as a guest particle to be composited (embedding).

At this time, since the embedding-coreshell proceeds according to the process time of the high-speed mixer in the embodiment, suitable process conditions for application to the supercapacitor may be different depending on the type of activated carbon and the conductive material.

According to the embodiment, in the same space of the conductive material uniformly mixed on the surface of the base material, the activated carbon can be present at the maximum and the conductive material can be present in the minimum ratio. Accordingly, the amount of the binder used in the supercapacitor electrode sheet can be used to a minimum.

6 is CV data of the electrochemical device according to the embodiment and the prior art.

According to the data of FIG. 6 , CV was measured at a sweep rate of 50 mV/s to compare the chemical stability and capacitance of Example (E1) and Comparative Example (R1).

As shown in the data of FIG. 6 , it can be confirmed that the CV window of the embodiment has a higher capacitance because the width is wider.

Accordingly, in the embodiment, since the amount of unnecessary binder and conductive material between the activated carbon and the activated carbon is minimized, as the ratio of the activated carbon increases, the ion adsorption power of the activated carbon is improved to increase the electrostatic capacity. A chemical element may be provided.

In addition, it can be confirmed that the Example has better reversibility characteristics because the symmetry is better than that of the Comparative Example.

7 is an electrochemical impedance analysis (EIS) data of the electrochemical device according to the embodiment and the prior art.

The data of FIG. 7 is a Nyquist plot obtained from electrochemical impedance analysis (EIS) of supercapacitor coin cells manufactured using Example (E2) and Comparative Example (R2).

The diameter of the semi-circle indicates the resistance between the electrode and the interface. As can be seen from the data, the x-axis semicircular diameter of Example (E2) is smaller than that of Comparative Example (R2), which means that the impedance between the electrode and the electrolyte is low. This is because the amount of unnecessary binder and conductive material between the activated carbon and the activated carbon of the embodiment is minimized.

Accordingly, according to the embodiment, as the conductive material is uniformly disposed on the surface of the activated carbon, the impedance between the electrode and the electrolyte is lowered, so that the electrode structure having the technical effect of increasing the capacitance according to the improvement of the electrical characteristics and the electrochemical including the same devices can be provided.

Specifically, in an embodiment, the composition layer for an electrode includes a base material and a conductive material disposed on the base material, and the density of the base material in the composition layer for an electrode may be higher than the density of the conductive material.

For example, when the tap density of the conductive material is about 0.1 g/ml, the tap density of the activated carbon serving as the base material may be about 0.5 to 0.7 g/ml. That is, the base material may have a tap density ratio of about 5 to 7 times that of the conductive material.

Reflecting this, if the input amount (g) of the base material activated carbon and the conductive material is calculated, about 35-40 g of activated carbon per 1 g of the conductive material can be added and mixed with a high speed mixer. That is, the base material may have a mass ratio of about 35 to 40 times that of the conductive material.

In the embodiment, although the particle size distribution of the active carbon and the conductive material as the base material is affected, when the tap density ratio and the mass ratio are less than the lower limit, there is a problem that the probability of the presence of the conductive material at the contact point between the base materials is reduced, thereby increasing the resistance, and exceeding the upper limit When an excessive amount of conductive material covers the base material, there is a technical problem in that it has a high resistance as in the prior art.

In addition, in an embodiment, when the composition layer for an electrode includes a base material, a conductive material, and a binder, the mass ratio in the electrode composition layer may be base material: conductive material: binder = about 93 to 97: about 2 to 3.5: about 2 to 3.5 have.

Meanwhile, when calculated based on the tap density in the composition layer for an electrode, the volume ratio may be: base material: conductive material: binder = about 83 to 87: about 12 to 15: about 1.0 to 2.0.

In the embodiment, when the mass ratio or volume ratio is less than the lower limit, the probability of the presence of a conductive material at the contact point between the base materials is reduced, and there is a technical problem that the resistance increases, and when an excess of the conductive material or binder covers the base material in excess of the upper limit, the resistance increases There is a technical problem.

8 is capacitance data of the electrochemical device according to the embodiment and the prior art.

As described above, through hybridization, activated carbon, which is the main material involved in ion adsorption and desorption, is present in a larger amount in the same volume than in the comparative example.

This means that the density increases, and the increase in the density of the electrode means that the capacitance, which is the main function of the supercapacitor, increases. Fig. 8 corresponds to the data, and it can be seen that the capacitance of Example (E3) is improved by about 20% compared to that of Comparative Example (R3).

In addition, as in Comparative Example (R3) of the prior art, the limit of the density occupied by the base material in the electrode composition layer is about 0.73 (g/cc).

For example, FIG. 8 shows experimental data of the coating type. As a result of testing with various base materials, the density of the electrode sheet of the coating type in the prior art is about 0.73 (g/cc) close to the maximum value.

However, when the embodiment is applied, the density occupied by the base material in the electrode composition layer may be about 0.75 (g/cc) or more. For example, if the embodiment is applied, the density occupied by the base material in the electrode composition layer can be secured from about 0.758 (g/cc) to a maximum of 0.772 (g/cc), through which the capacitance is significantly improved. There is a technical effect. At this time, the base material of the embodiment is a result when the present experiment is performed using activated carbon having a tap density of about 0.5 to 0.7 g/ml.

In the embodiment, when the lower limit of the density range occupied by the base material in the electrode composition layer is less than the lower limit, the capacitance may be low or peeling of the electrode material may occur, thereby causing a problem in long-term reliability.

Again, referring to FIG. 2 , in the embodiment, the electrochemical device 100 may include a plurality of separators. According to an embodiment, when the electrochemical device 100 includes a plurality of separators, a second separator 135 other than the separator 130 disposed between the first electrode 110 and the second electrode 120 . may be disposed on the first electrode 110 .

In an embodiment, the separator 130 may be disposed between the first electrode 110 and the second electrode 120 . Specifically, the separator 130 may be disposed in contact with the first electrode 110 and the second electrode 120 . Accordingly, the first electrode 110 , the separator 130 , and the second electrode 120 may be sequentially stacked to form the electrochemical device 100 according to the embodiment.

The electrochemical device 100 laminated including the first electrode 110 , the second electrode 120 , and the separator 130 may be impregnated with an electrolyte solution.

In an embodiment, the electrolyte may be a non-aqueous electrolyte. For example, when a non-aqueous electrolyte is used as the electrolyte in the embodiment, the electrolyte cation may be TEA ⁺ , TEMA ⁺ , Li ⁺ , EMIM ⁺ , Na ⁺ , and the like, and the electrolyte anion is BF ₄ ^- , PF ₆ ^- , TFSI ^- , FSI ^{- and the} like. In addition, the electrolyte solvent may be an organic electrolyte, more specifically, ACN, PC, GBL, DMK, or the like.

The concentration of the electrolyte may be different for each type of solvent and electrolyte ions.

In an embodiment, the first electrode 110 , the second electrode 120 , and the separator 130 disposed therebetween may have a structure disposed in the cover 140 . The cover 140 may be formed to include a conductive material. For example, the cover 140 may include a conductive material such as aluminum.

The embodiment has a technical effect that can provide an electrode structure capable of improving the energy density (E) by increasing the capacitance (C) and an electrochemical device including the same.

For example, in the embodiment, since the amount of unnecessary binder and conductive material between the activated carbon and the activated carbon is minimized, as the ratio of the activated carbon increases, the ion adsorption power of the activated carbon is improved and the electrostatic capacity is increased. It is possible to provide an electrochemical device that

Another object of the embodiment is to provide an electrode structure with improved electrical properties and an electrochemical device including the same.

For example, in the embodiment, as the conductive material is uniformly disposed on the surface of the activated carbon, the impedance (impedance) between the electrode and the electrolyte is lowered, so that the electrode structure having the technical effect of increasing the capacitance according to the improvement of the electrical properties and the electrochemical including the same devices can be provided.

Features, structures, effects, etc. described in the above embodiments are included in at least one embodiment, and are not necessarily limited to only one embodiment. Furthermore, features, structures, effects, etc. illustrated in each embodiment can be combined or modified for other embodiments by those of ordinary skill in the art to which the embodiments belong. Accordingly, the contents related to such combinations and variations should be interpreted as being included in the scope of the embodiments.

In the above, the embodiment has been mainly described, but this is only an example and does not limit the embodiment, and those of ordinary skill in the art to which the embodiment belongs are provided with several examples not illustrated above in the range that does not deviate from the essential characteristics of the embodiment. It can be seen that the transformation and application of branches are possible. For example, each component specifically shown in the embodiment can be implemented by modification. And the differences related to these modifications and applications should be interpreted as being included in the scope of the embodiments set forth in the appended claims.

Claims (9)

In the electrode structure comprising a base substrate and a composition layer for electrodes disposed on the base substrate,
The composition layer for the electrode,
It includes a base material and a conductive material disposed on the base material,
The density of the base material in the composition layer for the electrode is higher than the density of the conductive material,
The electrode structure of the electrochemical device in which the tap density of the base material in the composition layer for the electrode is 5 times or more of the tap density of the conductive material. delete According to claim 1,
The base material is an electrode structure of an electrochemical device having a tap density ratio of 5 to 7 times that of the conductive material. According to claim 1,
The electrode structure of the electrochemical device having a mass ratio in the range of 35 times to 40 times that of the base material in the composition layer for the electrode compared to the conductive material. According to claim 1,
The electrode composition layer further comprises a binder in addition to the base material and the conductive material,
The mass ratio in the electrode composition layer is,
Base material: Conductive material: Binder = 93 to 97: 2 to 3.5: Electrode structure of the electrochemical device of 2 to 3.5. According to claim 1,
The electrode composition layer further comprises a binder in addition to the base material and the conductive material,
The volume ratio based on the tap density in the electrode composition layer,
Base material: Conductive material: Binder = 83~87: 12~15: Electrode structure of an electrochemical device with 1.0~2.0. According to claim 1,
The electrode structure of the electrochemical device having a density of 0.75 (g/cc) or more of the base material in the composition layer for the electrode. 8. The method of claim 7,
The electrode structure of the electrochemical device having a density of 0.758 (g/cc) to 0.772 (g/cc) of the base material in the composition layer for the electrode. An electrochemical device comprising the electrode structure according to any one of claims 1 to 8.

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