KR102465449B1 - Fiber type cells comprising solid-state electrolyte and manufacture method thereof - Google Patents

Abstract

The present invention is a fiber-type battery, including lithium bis (trifluoromethanesulfonyl) imide (LiTFSI) and a carbonate-based solvent, including a first electrolyte layer in the form of a solid film having a viscosity of 400 cP or more at 25 ° C. It relates to a fiber-type solar cell used and a method for manufacturing the fiber-type solar cell. According to the above configuration, there are advantages in that photoelectric efficiency is high, there is no risk of leakage, device stability is provided, and design diversity can be pursued.

Description

Fiber type cells comprising solid-state electrolyte and manufacturing method thereof

The present invention relates to a fibrous battery containing a solid electrolyte and a method for manufacturing the same.

Research into using non-polluting clean energy such as solar energy as a new energy source instead of chemical fuels such as coal and oil is being actively conducted worldwide.

As a solar cell that has recently been in the spotlight, there is a wet solar cell having advantages such as low cost, environment-friendly, easy manufacturing process, and stability.

A wet solar cell is composed of a semiconductor electrode and an electrolyte. As an example of a typical wet solar cell, there is a combination type solar cell of an n-type semiconductor single crystal TiO ₂ electrode and a Pt electrode. Monocrystalline TiO ₂ of the wet solar cell When light is irradiated on the surface, electrons are excited and move to the conduction band, and when they reach the platinum electrode through the lead wire, they react with protons to generate hydrogen. According to the principle of a conventional wet solar cell, holes in the valence band take electrons from water molecules on the surface of TiO ₂ and annihilate to generate oxygen. At this time, instead of decomposing water, it is possible to generate electrical energy by using the resistance of an external circuit as a medium.

In order to solve the problem of low light utilization efficiency of the conventional wet solar cell, after adsorbing a dye that absorbs visible light on the surface of the semiconductor, light of a wavelength capable of being absorbed by the dye is irradiated to form a carrier of the semiconductor. An increasing type of wet solar cell has been developed. This type of wet solar cell is called a dye-sensitized solar cell or a Gratzell cell.

However, since the dye-sensitized solar cell needs to use a liquid electrolyte, it is necessary to create and seal a space between glass or plastic substrates with spacers adjusted by a spacer or the like, causing inconvenience in manufacturing as well as high cost. In addition, there was a problem in that the liquid electrolyte leaked. In order to solve this problem, a solar cell using a semi-solid electrolyte has been developed, but compared to the case of using a liquid electrolyte, the photoelectric efficiency is lower, and there is a problem in device stability.

As described above, in the case of a solar cell using a liquid electrolyte and a gel-type semi-solid electrolyte, there are problems such as leakage, high cost, and stability of the device.

Accordingly, there has been a demand for a solar cell having high photoelectric efficiency, no risk of leakage, and device stability.

On the other hand, with the advent of the wearable electronics era, which is a smart electronic device, the importance of power technology that can be directly introduced into wearable and E-Textile devices is emerging. to be.

However, currently commercialized batteries are standardized in the form of plate, cylindrical, prismatic, pouch, etc., and there is a limit to pursuing diversity in designs that can be directly introduced into smart electronic devices such as the wearable.

Korean Patent Registration No. 10-1799889 (2017.11.22.)

An object of the present invention is to provide a fiber-type battery including a solid electrolyte having high photoelectric efficiency, no risk of leakage, and device stability.

Another object of the present invention is to provide a fiber-type solar cell that has high photovoltaic efficiency, no risk of leakage, device stability, and can pursue design diversity.

Another object of the present invention is to provide a method for manufacturing a fiber-type solar cell capable of efficiently manufacturing a fiber-type solar cell having high photovoltaic efficiency, no risk of leakage, device stability, and design diversity.

According to one aspect, a fiber-type battery including a first electrolyte layer in the form of a solid film containing lithium bis (trifluoromethanesulfonyl) imide (LiTFSI) and a carbonate-based solvent and having a viscosity of 400 cP or more at 25 ° C. is provided.

According to one embodiment, the LiTFSI may be included in an amount of 60% by weight or more based on the total weight of the first electrolyte layer.

According to one embodiment, the carbonate-based solvent is dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), methylpropyl carbonate (MPC), ethylpropyl carbonate (EPC), methylethyl carbonate (MEC) ), ethylene carbonate (EC), propylene carbonate (PC), and butylene carbonate (BC).

According to one embodiment, the first electrolyte layer may have a viscosity of 500 to 800 cP at 25 °C.

According to one embodiment, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl formed on the first electrolyte layer (4-hydroxy-2,2,6,6-tetramethylpiperidine -1-oxyl, TEMPOL) may further include a second electrolyte layer containing the derivative.

According to one embodiment, the TEMPOL derivative may be TEMPOL p-toluenesulfonate (TpTS).

According to one embodiment, the conductivity of the first electrolyte layer may be greater than or equal to 1×10 ^-3 S/cm.

According to one embodiment, a fibrous inner core; a photoconductive layer formed on a surface of the fibrous inner core; an optoelectric material layer formed on a surface of the photoconductive layer; The solid film-type first electrolyte layer formed on the surface of the optoelectronic material layer; And an electrode layer formed on the surface of the solid film-type first electrolyte layer; including, it may be a solar cell.

According to an embodiment, the solar cell may further include a dye layer formed between the photoelectric material layer and the solid electrolyte layer, and may be a fuel-sensitized solar cell.

According to one embodiment, a second electrolyte layer may be further included on the electrode layer.

According to one embodiment, a protective layer may be further included on the second electrolyte layer.

According to another aspect, an article comprising the fibrous battery of the present disclosure is provided.

According to one embodiment, the article may be clothing or a portable battery.

According to another aspect, 1) preparing a fibrous inner core; 2) forming a photoconductive layer on the surface of the fibrous inner core; 3) forming an optoelectronic material layer on the surface of the photoconductive layer; 4) forming a solid film-type first electrolyte layer on the surface of the optoelectronic material layer; And 5) forming an electrode layer on the surface of the solid film-type first electrolyte layer; wherein, the first electrolyte layer is prepared in a film form having a viscosity of 400 cP or more at 25 ° C. after dissolving LiTFSI in a carbonate-based solvent That is, a method for manufacturing a fiber-type solar cell is provided.

According to one embodiment, in step 4), the first electrolyte layer may include 60% by weight or more of LiTFSI based on the total weight.

According to an embodiment, the method may further include forming a dye layer between the photoelectric material layer and the solid electrolyte layer.

According to one embodiment, it may further include forming a second electrolyte layer on the electrode layer.

According to one embodiment, the step of forming a protective layer on the second electrolyte layer may be further included.

According to one embodiment, the fiber-type battery including the solid film-type electrolyte of the present application has improved photoelectric efficiency, no leak concerns, and device stability can be improved.

According to an embodiment, the fiber-type solar cell of the present application has improved photovoltaic efficiency, no risk of leakage, improved device stability, and various design applications, so it can be usefully used in smart electronic devices such as wearables.

According to an embodiment, by using a solid electrolyte that can be mass-produced in a large-area roll-to-roll process, a fiber-type solar cell having high photoelectric efficiency, no risk of leakage, device stability, and design diversity can be efficiently produced. can be manufactured with

1A is a diagram schematically showing a fiber-type solar cell including a solid film-type electrolyte according to an embodiment of the present invention.
1b is a SEM image and photograph of a fiber-type solar cell including a solid film-type electrolyte according to an embodiment of the present invention.
2 is a diagram schematically showing a method of manufacturing a fiber-type solar cell including a solid film-type electrolyte according to an embodiment of the present invention.
3 is a graph showing the efficiency of a solar cell based on a fibrous solid/semi-solid electrolyte.
4 is a diagram showing a change in viscosity according to the amount of LiTFSI of a solid film electrolyte according to an embodiment of the present invention.
Figure 5a is a graph showing the change in conductivity according to the type of TEMPOL derivative of the solid film-type electrolyte according to an embodiment of the present invention.
Figure 5b is a graph showing the absorbance change according to the type of TEMPOL derivative of the solid film-type electrolyte according to an embodiment of the present invention.
6A is a graph showing the change in current density of a solar cell according to the type of TEMPOL derivative.
6B is a graph showing the EQE spectrum and integrated current of a solar cell according to the type of TEMPOL derivative.
6C is a graph showing the efficiency of a solar cell according to the type of TEMPOL derivative.
7 is a graph showing the characteristics of the laboratory and external solar cells of the TEMPOL-SS-FDSSCs device.
8 is a photograph showing a washability test of a fiber-type solar cell according to an embodiment of the present invention.
9 is a photograph showing a bending test of a fiber-type solar cell according to an embodiment of the present invention.
10A is a graph showing a change in photovoltaic efficiency after a bending test of a fiber-type solar cell according to an embodiment of the present invention.
10B is a graph showing a change in photovoltaic efficiency according to a radial size of a fiber-type solar cell according to an embodiment of the present invention.
FIG. 10C is a graph showing the operation of an electrochromic device after series connection of fiber-type solar cells according to an embodiment of the present invention.
10D is a graph showing a change in photovoltaic efficiency after a washing test of a fiber-type solar cell according to an embodiment of the present invention.

Terms used in this application are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, the terms "include" or "have" are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features It should be understood that the presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded. And, throughout the specification, "on" means to be located above or below the target part, and does not necessarily mean to be located on the upper side with respect to the direction of gravity.

In addition, coupling does not mean only the case of direct physical contact between each component in the contact relationship between each component, but another configuration intervenes between each component so that the component is in the other configuration. It should be used as a concept that encompasses even the case of contact with each other.

Since the present invention can apply various transformations and have various embodiments, specific embodiments will be illustrated in the drawings and described in detail in the detailed description. However, it should be understood that this is not intended to limit the present invention to specific embodiments, and includes all transformations, equivalents, and substitutes included in the spirit and scope of the present invention.

In describing the present invention, if it is determined that a detailed description of related known technologies may obscure the gist of the present invention, the detailed description will be omitted.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In order to facilitate overall understanding in describing the present invention, the same reference numerals will be used for the same means regardless of the drawing numbers.

Since the size and thickness of each component shown in the drawings are arbitrarily shown for convenience of description, the present invention is not necessarily limited to the shown bar.

In the description with reference to the accompanying drawings, the same or corresponding components are assigned the same reference numerals, and overlapping descriptions thereof will be omitted.

fiber battery

According to one aspect, a fiber-type battery including a first electrolyte layer in the form of a solid film containing lithium bis (trifluoromethanesulfonyl) imide (LiTFSI) and a carbonate-based solvent and having a viscosity of 400 cP or more at 25 ° C. is provided.

The first electrolyte layer included in the fiber-type battery of the present application is characterized in that it is in the form of a solid film. Therefore, in the case of the fibrous battery of the present application, there is no risk of leakage occurring when a semi-solid electrolyte such as liquid or gel is included, and device stability can be provided.

Furthermore, it is prepared in the form of a solid film by including lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and a carbonate-based solvent, but has excellent photoelectric efficiency. As shown in FIG. 3, the photovoltaic efficiency of the solar cell based on the solid film type first electrolyte of the present application was 6.71%. This is not only significantly improved from the highest photoelectric efficiency of 5% of currently known solid electrolyte-based solar cells, but also higher than the highest photoelectric efficiency of 6.23% of semi-solid-based solar cells.

Although not limited thereto, the viscosity of the solid film-type first electrolyte layer of the present application is 400 cP or more measured using a Brockfield viscometer at 25 ° C, and the viscosity of the liquid electrolyte is 0 to 1, the viscosity of the semi-solid electrolyte is 3 to 1 significantly higher than 50.

Although not limited thereto, the viscosity of the solid film-type first electrolyte layer of the present application may be suitable in terms of processability and economy when the viscosity of 500 to 800 cP measured using a Brookfield viscometer at 25 ° C.

Although not limited thereto, the LiTFSI containing 60% by weight or more relative to the total weight of the first electrolyte layer may be suitable in terms of processability and economy when forming the solid film-type first electrolyte layer, and 60 to 70% by weight % may be more appropriate (see Figure 4).

Although not limited thereto, the carbonate-based solvent is dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), methylpropyl carbonate (MPC), ethylpropyl carbonate (EPC), methylethyl carbonate (MEC ), ethylene carbonate (EC), propylene carbonate (PC), and butylene carbonate (BC).

Although not limited thereto, the first electrolyte may be prepared by a known film formation process such as casting, blade coating, or dip coating after dissolving LiTFSI in a carbonate-based solvent. In addition, mass production is possible by a large-area roll-to-roll process, and the first electrolyte layer can be easily formed by preparing a large-area solid electrolyte and then cutting it into a predetermined size and wrapping it in a fiber-type battery or the like.

Although not limited thereto, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl formed on the first electrolyte layer (4-hydroxy-2,2,6,6-tetramethylpiperidine -1-oxyl, TEMPOL) may further include a second electrolyte layer containing the derivative. Including the second electrolyte layer, it is possible to improve the conductivity of the fiber-type battery.

Although not limited thereto, the TEMPOL derivative may be TEMPOL acetate (TA), TEMPOL benzosulfonate (TBS), and TEMPOL p-toluenesulfonate (TpTS) represented by the formula below, and TEMPOL p-toluenesulfonate (TpTS) may be most suitable in terms of conductivity enhancement.

Although not limited thereto, the conductivity of the first electrolyte layer may be 1×10 ^-4 S/cm, and the conductivity may increase to 1×10 ^-3 S/cm or more when the TEMPOL derivative is treated. As shown in FIG. 5, the conductivity was 4×10 ^-4 S/cm when treated with TA, 8.9×10 ^-4 S/cm when treated with TBS, and 4.3×10 -4 S/cm when treated with ^TpTS . ³ S/cm.

The fiber-type battery of the present application refers to a battery having a fiber-like shape, and may have a spherical or modified spherical oval shape in cross section, and the length of the battery may vary depending on the manufacturing method or use. Although not limited thereto, the fiber-type battery may be a lithium secondary battery, a supercapacitor, a fuel-sensitized fuel cell, a flexible battery, or a fuel-sensitized solar cell, and a fuel-sensitized solar cell may be suitable.

fiber solar cell

1A is a diagram schematically showing a fiber-type solar cell including a solid film-type electrolyte according to an embodiment of the present invention, and FIG. 1B is a fiber-type solar cell including a solid film-type electrolyte according to an embodiment of the present invention. These are SEM images and photographs of the cells.

Referring to FIGS. 1A and 1B , a dye-sensitized fiber-type solar cell according to an embodiment includes a fiber-type inner core 10; a photoconductive layer 20 formed on the surface of the fibrous inner core 10; an optoelectronic material layer 30 formed on the surface of the photoconductive layer 20; a dye layer 40 formed on the optoelectronic material layer 30; The solid film type first electrolyte layer 50 formed on the surface of the dye layer 40; And an electrode layer 60 formed on the surface of the solid film-type first electrolyte layer 50; may include.

The fibrous inner core 10 is a working electrode, but is not limited thereto, Ti may be a wire.

The photoconductive layer 20 is TiO ₂ After washing the Ti wire, both ends of the Ti wire are bitten by a power supply and a current is applied to obtain micro TiO ₂ It can be formed as a compact TiO ₂ layer. The photoconductive layer 20 serves to transfer electrons excited by photons absorbed by the photosensitive dye absorbing sunlight to the electrode.

The optoelectronic material layer 30 is not limited thereto, but mesoporous TiO ₂ can be layered. The mesoporous TiO ₂ The layer is Miso TiO ₂ A wire formed of a compact TiO ₂ layer may be formed by dip-coating a TiO ₂ solution and heat-treating the wire.

The dye layer 40 includes a ruthenium-containing complex, an osmium-containing complex, an iron complex, or a super macromolecule containing 2 or 3 transition metals capable of effectively absorbing sunlight and generating photovoltaic power by including a photosensitive dye It is preferable that it is a complex. The ligand contained in the photosensitive dye of the present invention may be a bidentate chelate, tridentate chelate or multi-chelate polypyridyl compound, and at least one of the polypyridyl compounds may contain a cyano group. In one embodiment of the present application, ruthenium-based N719 was used as a specific example of the photosensitive dye, but is not limited thereto.

The first electrolyte layer 50 may be formed by lapping the dye layer 40 in the above-described solid film type. The first electrolyte layer 50 includes lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and a carbonate-based solvent, and has a viscosity of 400 cP or more at 25°C.

The electrode layer 60 is a counter electrode and may be formed of a Pt wire. By winding the first electrolyte layer 50 with a Pt wire, the first electrolyte layer 50 may be fixed so as not to be unwound.

According to one embodiment, a second electrolyte layer 70 may be further included on the electrode layer 60 . Although not limited thereto, the second electrolyte layer 70 may be formed of a TEMPOL derivative to improve conductivity. The TEMPOL derivative may be TEMPOL acetate (TA), TEMPOL benzosulfonate (TBS), and TEMPOL p-toluenesulfonate (TpTS), and TEMPOL p-toluenesulfonate (TpTS) may be most suitable in terms of conductivity improvement. have.

According to one embodiment, a protective layer 80 may be further included on the second electrolyte layer 70 . The protective layer 80 may be formed by putting it in a transparent Teflon tube and sealing it.

An article comprising the fiber-type battery of the present disclosure is provided.

The article may be clothing or a portable battery.

As research to manufacture flexible and wearable solar cells is actively progressing, solar cells in the form of hard and flat substrates have been replaced with flexible substrates. In an attempt to make the fiber itself an energy generating device beyond the technology of carrying a flexible solar cell, a technology for implementing a single strand of fiber into a solar cell is being developed. As such, the fiber-type solar cell is a technology that produces and stores energy by implementing a solar cell device in a single fiber used in clothing manufacturing.

Manufacturing method of fiber type solar cell

2 is a diagram schematically showing a method of manufacturing a fiber-type solar cell including a solid film-type electrolyte according to an embodiment of the present invention.

Referring to Figure 2, the fiber-type solar cell manufacturing method of the present application consists of the following steps:

1) preparing a fibrous inner core 10 (S10);

2) forming a photoconductive layer 20 on the surface of the fibrous inner core 10 (S20);

3) forming an optoelectronic material layer 30 on the surface of the photoconductive layer 20 (S30);

4) forming a dye layer 40 on the surface of the optoelectronic material layer 30 (S40);

5) forming a solid film-type first electrolyte layer 50 on the surface of the dye layer 40 (S50);

6) forming an electrode layer 60 on the surface of the solid film first electrolyte layer 50 (60);

7) forming a second electrolyte layer 70 on the electrode layer 60; and

8) Forming a protective layer 80 on the surface of the second electrolyte layer 70.

The first electrolyte layer 50 is prepared in the form of a film having a viscosity of 400 cP or more at 25° C. after dissolving LiTFSI in a carbonate-based solvent.

In step 1), the fibrous inner core 10 is a working electrode, but is not limited to Ti. It can be made of wire.

In step 2), the photoconductive layer 20 is TiO ₂ After washing the Ti wire, both ends of the Ti wire are bitten by a power supply and a current is applied to obtain micro TiO ₂ It can be formed as a compact TiO ₂ layer.

In step 3), the optoelectronic material layer 30 may be, but is not limited to, a mesoporous TiO ₂ layer. The mesoporous TiO ₂ The layer is Miso TiO ₂ A wire formed of a compact TiO ₂ layer may be formed by dip-coating a TiO ₂ solution and heat-treating the wire.

In step 4), the dye layer 40 includes a photosensitive dye and contains a ruthenium-containing complex, an osmium-containing complex, an iron complex, or two or three transition metals that can effectively absorb sunlight and generate photovoltaic power. It is preferable that it is a supramolecular complex that The ligand contained in the photosensitive dye of the present invention may be a bidentate chelate, tridentate chelate or multi-chelate polypyridyl compound, and at least one of the polypyridyl compounds may contain a cyano group. In one embodiment of the present application, ruthenium-based N719 was used as a specific example of the photosensitive dye, but is not limited thereto.

In step 5), the first electrolyte layer 50 may be formed by lapping the dye layer 40 in the above-described solid film shape. The first electrolyte layer 50 is prepared by casting, blade coating, or dip coating by mixing lithium bis (trifluoromethanesulfonyl) imide (LiTFSI) and a carbonate-based solvent, and has a viscosity of 400 cP at 25 ° C. It is characterized by more than The first electrolyte layer 50 may include 60% by weight or more of LiTFSI based on the total weight.

In step 6), the electrode layer 60 may be formed of a Pt wire as a counter electrode. By winding the first electrolyte layer 50 with a Pt wire, the first electrolyte layer 50 may be fixed so as not to be unwound.

In step 7), the second electrolyte layer 70 is formed of a TEMPOL derivative to improve conductivity. The second electrolyte layer 70 may be formed by dipping into a TEMPOL derivative. The TEMPOL derivative may be TEMPOL acetate (TA), TEMPOL benzosulfonate (TBS), and TEMPOL p-toluenesulfonate (TpTS), and TEMPOL p-toluenesulfonate (TpTS) may be most suitable in terms of conductivity improvement. have.

In step 8), the protective layer 80 may be formed by putting it in a transparent Teflon tube and sealing it.

[ Example ]

Hereinafter, the present invention will be described in more detail through examples.

Preparation of solid film first electrolyte

LiTFSI salt was dissolved by adding 3 weight percent (wt%) to a propylene carbonate solution. During the casting process for producing a LiTFSI film, the prepared solution was slowly poured into a wide and flat container while being careful not to generate bubbles, and then dried. A LiTFSI film was prepared through a curing process by irradiating a wide and flat solution with an ultraviolet lamp.

Preparation of the second electrolyte

TpTS powder was prepared to coat the TEMPOL derivative layer. First, a p-toluenesulfonyl chloride solution was dissolved in a TEMPOL solution in a dropwise manner, and then dried in dichloromethane at 0° C. to which pyridine was added. After rinsing the mixture, it was mixed for 10 hours at 20 °C. After repeating the process three times, 10% hydrochloric acid was added to the mixture and extracted with dichloromethane. After drying with magnesium sulfate, it was evaporated. The prepared raw material was purified through column chromatography, and crystallized TpTS was obtained through a vacuum drying process.

Manufacturing method of fiber type solar cell

Ti wire used as a working electrode was cut to a length of 80 mm to fabricate a fiber-type solar cell in the form of a unit cell. The Ti wire was sequentially immersed in acetone and isopropyl alcohol (IPA) and washed in an ultrasonic cleaner for 10 minutes each. Micro TiO ₂ A compact TiO ₂ layer is formed. Miso TiO ₂ The layer was formed when Ti was oxidized as oxygen in the air reacted with the Ti wire by an applied current.

To coat the mesoporous TiO ₂ layer, a TiO ₂ solution diluted with TiO ₂ paste and ethanol at a ratio of 1:1 wt% was prepared. After dip-coating the wire on which fine TiO ₂ was formed in the prepared TiO ₂ solution, heat treatment was performed at 120° C. for 3 minutes. The dip coating and heat treatment processes were repeated a total of 5 times. The wire coated with the TiO ₂ layer 5 times was heat treated in a furnace for 8 hours to form a mesoporous TiO ₂ layer.

The photoelectrode wire thus completed was immersed in the N719 dye solution for 15 hours to adsorb the N719 dye layer onto the mesoporous TiO ₂ layer.

Next, a first electrolyte layer was formed by winding the solid film type LiTFSI around the photoelectrode wire to which the dye layer was adsorbed.

A Pt wire, which is a counter electrode, was wound around where the LiTFSI solid film was wound to maintain the shape of the LiTFSI film so that it would not unwind.

To adsorb the TEMPOL derivative layer, TpTS powder was dissolved in an acetonitrile solution at 5 wt%. The photoelectrode wire on which the LiTFSI solid film and the dye layer around the Pt wire were adsorbed was immersed in the TpTS solution for 30 minutes to adsorb the second electrolyte layer, and then dried at room temperature.

The fabricated fiber-type solar cell was placed in a transparent Teflon tube and sealed at both ends using optical bonds.

result

Figure 5a is a graph showing the change in conductivity according to the type of TEMPOL derivative of the solid film-type electrolyte according to an embodiment of the present invention. When TpTs powder was added among the TEMPOL derivatives, it was confirmed that the conductivity was improved, and when such an electrolyte layer was included, the conductivity of the fibrous battery could be improved.

Figure 5b is a graph showing the absorbance change according to the type of TEMPOL derivative of the solid film-type electrolyte according to an embodiment of the present invention. Compared to the conventional solid film-type electrolyte, it can be confirmed that the absorbance of the electrolyte layer is reduced when the TEMPOL derivative is added. Therefore, when such an electrolyte layer is included, most of the light incident from the outside can be absorbed by the photocatalyst TiO ₂ and the dye, thereby improving the light absorption characteristics of the fiber-type battery. The reference, which is the conventional solid film electrolyte, is an iodine-based solid electrolyte adsorbed on a Li-TFSI film. The electrolyte film of the present application has a central absorption peak at approximately 460 nm and a wide absorption range at 350 to 600 nm. TEMPOL derivatives have lower absorbance compared to the reference while having higher transmittance. Therefore, having a high current density in a solid fiber solar cell results in sufficient exciton absorption into the dye at an enhanced incident angle. In addition, measurements of the ionic conductivity of the solid electrolyte were determined by impedance measurement.

The AC conductivity, which is mainly frequency dependent, is given by the above equation.

The real part of the impedance is Z(w), Z'(w) is the imaginary part of the impedance, L is the thickness of the cell, and A is the effective area.

In Fig. 5a, the high ionic conductivity of the tpTs electrolyte shows a high-performance solid-state fibrous solar cell with an increase in Jsc (current density) value due to sufficient charge extraction from the dye to the Pt electrode. The p(para)-toluenesulfonate group of TEMPOL is more effective for ionic conductivity than either the acetyl or benzenesulfonate groups. The introduction of a methyl group into the aromatic ring group of TpTS improves ionic conductivity due to electron donating effect and helps to activate the benzene ring.

In a basic solid-state fiber-type solar cell, photoelectric characteristics are determined by four important parameters. They are open circuit voltage (Voc), short circuit current (Jsc), charge factor (FF), and photoelectric efficiency (PCE). The effective area of the solid fiber solar cell was calculated by multiplying the diameter and length of one electrode in a fixed state using a 20 mm mask. The current density-voltage curve under AM 1.5 is shown in FIG. 6a.

That is, FIG. 6A is a graph showing a change in current density of a solar cell according to the type of TEMPOL derivative. In the device to which the TEMPOL derivative was added, it was confirmed that the current density was improved by increasing the light absorption and conduction characteristics of the device.

6B is a graph showing the EQE spectrum and integrated current of a solar cell according to the type of TEMPOL derivative. In the device to which the TEMPOL derivative was added, it was confirmed that the current density was improved by increasing the light absorption and conduction characteristics of the device.

6C is a graph showing the efficiency of a solar cell according to the type of TEMPOL derivative. In the case of adding TpTs among the TEMPOL derivatives, it can be seen that the efficiency of the 4% level is improved to 6%.

The solid fiber solar cell fabricated using the TEMPOL derivatives had a higher current density than the reference solar cell. The measured current densities were reference (8.59 mA/cm 2 ), TA (9.88), TBS (11.37 mA/cm 2 ), and TpTs (12.09 mA/cm 2 ). It is associated with increased ionic conductivity and high permeability of the electrolyte. The solid fiber solar cell using TpTs showed the highest efficiency of 6.16%. It was scanned with a time of 150 mS to minimize hysteresis. The photoelectric efficiency in the forward scan was 6.16% and the photoelectric efficiency in the reverse scan was 6.02%, and the error range was about 2%. TpTS, a solid electrolyte, has multifunctionality with a benzene ring with a methyl group and a sulfonate group. The sulfonate of TpTS is an electron-accepting group. The methyl group on the aromatic ring of TpTS increases the conductivity by activating the benzene ring and acting as an electron donor.

Table 1 is a table showing photoelectric characteristics of fiber-type solar cells.

7 is a graph showing the characteristics of the laboratory and external solar cells of the TEMPOL-SS-FDSSCs device. This shows that the fiber-type solar cell can be operated in actual external and indoor environments. Looking more specifically, a of FIG. 7 shows the efficiency of the solid fiber solar cell at 0.2 to 1 Sun. Various illuminance and amount of sunlight were investigated in an outdoor environment and can be expressed as maximum power (P _max ) as shown in b of FIG. Therefore, the maximum power can be expressed as current density X open voltage X charging rate. It increased from 50,000 W/m2 to 60,000 W/m2 from 9:30 am to midnight. After that, it rapidly decreased to 10,000 W/m2 at 3:30 PM. This phenomenon tended to be almost similar to the maximum power value in the solar cell. The values of the fitted series resistance were 124.6Ω for reference, 76.2Ω for TA, 74.4Ω for TBS, and 64.8Ω for TpTS. The internal resistance, Rs, was the lowest in the TpTS-based fiber type solar cell. On the other hand, the references of R _CE and R _WE are 289.8Ω and 1318Ω, TA are 215.7Ω and 806Ω, TBS are 85.5Ω and 411Ω, and TpTS are 68.8Ω and 299Ω. The small R _CE and R _WE of the TBS and TpTS solid fiber solar cells are also the result of the sulfonate group and the fast charge-transport process from the high electrical conductivity in the activated material, as shown in the molecular structure of Fig. 7a. In addition, the methyl group linked to the tail of TpTS showed better ionic conductivity than TBS. The increase in the charge factor (FF) of solid fiber solar cells made with tempol derivatives was further explained by measuring the dark curve at room temperature. The ratios in the steady state were 1.06×10 ⁵ , 5.88×10 ⁵ , 1.86×10 ⁶ , and 9.01×10 ⁶ for the reference, TA, TBS, and TpTS solar cells. Thus, a sufficiently improved shact resistance (R _sh ) and reduced series resistance (R _s ) showed an improvement in transport efficiency and charge extraction and a decrease in leakage current.

8 is a photograph showing a washability test of a fiber-type solar cell according to an embodiment of the present invention, and FIG. 9 is a photograph showing a bending test of a fiber-type solar cell according to an embodiment of the present invention.

The solid-state fiber-type solar cell of the present application has a diameter of 250 μm and is easily bendable due to high flexibility. 10A is a graph showing a change in photovoltaic efficiency after a bending test of a fiber-type solar cell according to an embodiment of the present invention. As shown in FIG. 10A, the change in photoelectric efficiency is not large even after 500 or more bending tests.

10B is a graph showing a change in photovoltaic efficiency according to a radial size of a fiber-type solar cell according to an embodiment of the present invention. As shown in FIG. 10B, the change in photoelectric efficiency is not large even when bending from 5 mm to 1 mm. Furthermore, 92% of the initial efficiency was maintained even under high tension and stress due to contraction and extension during bending.

FIG. 10C is a graph showing the operation of an electrochromic device after series connection of fiber-type solar cells according to an embodiment of the present invention. In order to realize the purpose of the wearable device, the fabricated solid fiber-type solar cells were connected in series and sewn into clothes as shown in FIG. 10c. Roughly, when connected in series, it had an open-circuit voltage of 2.4V, and could sufficiently operate the liquid crystal device. As shown in a of FIG. 7 , the characteristics of the stable open-circuit voltage of the solid-state fiber solar cell under low illumination successfully drove an LCD device in an office without an additional optical power source.

10D is a graph showing a change in photovoltaic efficiency after a washing test of a fiber-type solar cell according to an embodiment of the present invention. The fiber-type solar cell exhibits stable photovoltaic efficiency even after washing.

Although one embodiment of the present invention has been described above, those skilled in the art can add, change, delete, or add components within the scope not departing from the spirit of the present invention described in the claims. The present invention can be variously modified and changed by the like, and this will also be said to be included within the scope of the present invention.

10: fibrous inner core
20: photoconductive layer
30: photoelectric material layer
40: dye layer
50: first electrolyte layer
60: electrode layer
70: second electrolyte layer
80: protective layer

Claims (18)

A fiber-type battery comprising a first electrolyte layer in the form of a solid film containing lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and a carbonate-based solvent and having a viscosity of 400 cP or more at 25°C. According to claim 1,
The LiTFSI is a fiber-type battery comprising 60% by weight or more based on the total weight of the first electrolyte layer. According to claim 1,
The carbonate-based solvent is dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), methylpropyl carbonate (MPC), ethylpropyl carbonate (EPC), methylethyl carbonate (MEC), ethylene carbonate (EC ), propylene carbonate (PC), and at least one selected from butylene carbonate (BC), a fiber-type battery. According to claim 1,
The first electrolyte layer has a viscosity of 500 to 800 cP at 25 ° C., a fibrous battery. According to claim 1,
4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPOL) formed on the first electrolyte layer ), a fiber-type battery further comprising a second electrolyte layer comprising a derivative. According to claim 5,
A fiber-type battery, wherein the TEMPOL derivative is TEMPOL p-toluenesulfonate (TpTS). According to claim 1,
The conductivity of the first electrolyte layer is 1 × 10 ^-3 S / cm or more, a fibrous battery. According to claim 1,
a fibrous inner core;
a photoconductive layer formed on a surface of the fibrous inner core;
an optoelectric material layer formed on a surface of the photoconductive layer;
The solid film-type first electrolyte layer formed on the surface of the optoelectronic material layer; and
An electrode layer formed on the surface of the solid film-type first electrolyte layer; including, a solar cell, a fiber-type battery. According to claim 8,
Further comprising a dye layer formed between the photoelectric material layer and the solid electrolyte layer, the fuel-sensitized solar cell, a fiber-type cell. According to claim 9,
A fiber-type battery further comprising a second electrolyte layer on the electrode layer. According to claim 10,
A fuel-sensitized solar cell further comprising a protective layer on the second electrolyte layer, a fibrous battery. An article comprising the fiber-type battery according to any one of claims 1 to 11. According to claim 12,
The article is an article, clothing or a portable battery. 1) preparing a fibrous inner core;
2) forming a photoconductive layer on the surface of the fibrous inner core;
3) forming an optoelectronic material layer on the surface of the photoconductive layer;
4) forming a solid film-type first electrolyte layer on the surface of the optoelectronic material layer; and
5) forming an electrode layer on the surface of the solid film first electrolyte layer;
The first electrolyte layer is prepared in the form of a film having a viscosity of 400 cP or more at 25 ° C. after dissolving LiTFSI in a carbonate-based solvent, a method for manufacturing a fiber-type solar cell. According to claim 14,
In step 4), the first electrolyte layer includes LiTFSI in an amount of 60% by weight or more based on the total weight. According to claim 15,
Further comprising the step of forming a dye layer between the photoelectric material layer and the solid electrolyte layer, fiber-type solar cell manufacturing method. According to claim 16,
Further comprising the step of forming a second electrolyte layer on the electrode layer, fiber-type solar cell manufacturing method. According to claim 17,
Further comprising the step of forming a protective layer on the second electrolyte layer, fiber-type solar cell manufacturing method.

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