KR102491143B1 - Solid state electrolyte operating in high and low temperature, method of fabricating of the same, and metal air battery comprising the same - Google Patents

Abstract

A solid electrolyte is provided. The solid electrolyte includes a plurality of base fibers forming a network, the base composite fibers include cellulose and chitosan bonded to each other, and when the solid electrolyte is installed in a metal-air battery, a wide range of temperatures from low to high temperatures It can operate stably in the range.

Description

Solid state electrolyte operating in high and low temperature, method of fabricating of the same, and metal air battery comprising the same}

The present application relates to a solid electrolyte, a manufacturing method thereof, and a metal-air battery including the same, and more particularly, a solid electrolyte maintaining high reliability and high ion conductivity in a high temperature environment and a low temperature environment, a manufacturing method thereof, and the same It relates to a metal-air battery comprising

The market value of the secondary battery industry was only about 22 billion dollars in 2018, as mid- to large-sized high-energy applications such as electric vehicles and energy storage systems (ESS) are rapidly growing beyond the existing secondary batteries for small devices and home appliances. However, it is expected to grow to about 118 billion dollars in 2025. As such, in order for secondary batteries to be used as medium and large-sized energy storage media, significantly improved price competitiveness, energy density, and stability are required.

According to these technical needs, research on secondary batteries using solid electrolytes is being actively conducted.

For example, International Patent Publication WO2014200198A1 discloses a composite electrode-composite electrolyte composite in which a composite electrode layer and a composite electrolyte layer are integrated, wherein the composite electrode layer includes a current collector and an electrode mixture layer formed on the current collector, and the electrode mixture layer A silver electrode active material, a conductive material, a cross-linked polymer matrix, a dissociable salt, and an organic solvent are included, the composite electrolyte layer includes a cross-linked polymer matrix, inorganic particles, a dissociable salt, and an organic solvent, and the electrode mixture layer and The composite electrolyte layer discloses a composite electrode-composite electrolyte composite comprising overlapping and physically bonding

에서 소결하는 제7 단계를 포 함하고, 소결체의 상대밀도(%)가 90.0 내지 99.7이고, 이온전도도(S cm^-1 )가 7.9 Х 10^-4 내지 9.9 Х 10^-4를 갖는 것을 특징으로 하는 리튬전지용 고체전해질의 제조방법이 개시되어 있다. For another example, in Korean Patent Registration Publication No. 10-1734301, a first metal precursor made of a Li precursor, a second metal precursor made of an Al precursor, a third metal precursor made of a Ti precursor, and a P precursor are reacted with a chelating agent. The first step of preparing a sol by heating the sol, the second step of heating the sol to produce a gel, the third step of heating and thermally decomposing the gel, heat treatment while contacting the thermally decomposed gel with air The fourth step, the fifth step of cooling the powder obtained through the fourth step, the sixth step of mixing 0.2 to 1 wt% of the sintering aid Bi ₂ O ₃ with the powder cooled in the fifth step, and the sixth step. 850 while pressurizing and contacting the mixed powder obtained in

Including a seventh step of sintering in, the relative density (%) of the sintered body is 90.0 to 99.7, and the ionic conductivity (S cm ^-1 ) is 7.9 Х 10 ^-4 to 9.9 Х 10 ^-4 Characterized in that it has A method of manufacturing a solid electrolyte for a lithium battery is disclosed.

One technical problem to be solved by the present application is to provide a solid electrolyte capable of operating in high and low temperature environments and a manufacturing method thereof.

Another technical problem to be solved by the present application is to provide a solid electrolyte that maintains high ionic conductivity in high and low temperature environments and a manufacturing method thereof.

Another technical problem to be solved by the present application is to provide a solid electrolyte that is flexible and has high mechanical stability in high and low temperature environments and a manufacturing method thereof.

Another technical problem to be solved by the present application is to provide a metal-air battery including a solid electrolyte capable of operating in high and low temperature environments.

Another technical problem to be solved by the present application is to provide a metal-air battery having a high charge and discharge capacity and a long lifespan in high and low temperature environments.

The technical problem to be solved by the present application is not limited to the above.

In order to solve the above technical problem, the present application provides a solid electrolyte.

According to one embodiment, in the solid electrolyte in which a plurality of base composite fibers form a network, the base composite fibers include cellulose and chitosan bonded to each other, and when the solid electrolyte is installed in a metal-air battery, - It may include operating the metal-air battery from 20 ° C to 80 ° C.

According to one embodiment, the cellulose may include bacterial cellulose.

According to one embodiment, the solid electrolyte includes a first composite fiber in which the surface of the base composite fiber is oxidized, and a second composite fiber in which the surface of the base composite fiber is bonded to a first functional group having nitrogen, The plurality of first composite fibers and the plurality of second composite fibers may be cross-linked to form a network.

According to one embodiment, the ratio of the first composite fiber is greater than 30wt% and less than 70wt%, and the ratio of the second composite fiber may include less than 70wt% and greater than 30wt%.

According to one embodiment, the metal-air battery may include zinc as an anode.

According to an embodiment, crystallinity, ionic conductivity, and swelling ratio of the solid electrolyte may be controlled according to the ratio of chitosan.

In order to solve the above technical problem, the present application provides a metal-air battery.

According to one embodiment, the metal-air battery includes a positive electrode using oxygen as a positive electrode active material, a negative electrode including a metal, and a solid electrolyte disposed between the positive electrode and the negative electrode, wherein the solid electrolyte may include a network formed of a plurality of base composite fibers and operated at -20°C to 80°C.

According to an embodiment, the discharge capacity may increase as the temperature increases within -20°C to 80°C.

According to one embodiment, the negative electrode may include zinc, and the positive electrode may include a compound including a transition metal, phosphorus, and a chalcogen element.

According to one embodiment, the base composite fiber of the solid electrolyte may include cellulose and chitosan bonded to each other, but the proportion of the chitosan in the solid electrolyte may include more than 30wt% and less than 70wt%.

According to an embodiment, the solid electrolyte may include a first composite fiber in which a surface of the base composite fiber is oxidized, and a second composite fiber in which a surface of the base composite fiber is bonded to a first functional group having nitrogen. there is.

According to one embodiment, the cellulose of the base composite fiber may include bacterial cellulose.

The solid electrolyte according to an embodiment of the present application may include a plurality of base composite fibers forming a network, and the base composite fibers may include cellulose and chitosan bonded to each other.

The metal-air battery including the solid electrolyte can perform charging and discharging operations from -20°C to 80°C, and thus a solid electrolyte that can be stably used in high and low-temperature environments and a metal-air battery including the same will be provided. can

1 is a view showing a base composite fiber according to an embodiment of the present application.
2 is a view showing a first composite fiber according to an embodiment of the present application.
3 is a view showing a second composite fiber according to an embodiment of the present application.
4 is a diagram illustrating a solid electrolyte including a base composite fiber according to an embodiment of the present application.
5 is a diagram illustrating a metal-air battery including a solid electrolyte according to an embodiment of the present application.
6 is a view for explaining a first composite fiber and a manufacturing method thereof according to Experimental Examples 1-2 of the present application.
7 is a view for explaining a second composite fiber and a manufacturing method thereof according to Experimental Examples 1-3 of the present application.
8 is a diagram for explaining a method of manufacturing a solid electrolyte according to Experimental Examples 1-4 of the present application.
9 is a diagram for explaining the principle of ion movement of the solid electrolyte according to Experimental Examples 1-4 of the present application.
10 is a hydrogen NMR analysis result of the first composite fiber, the second composite fiber, and the solid electrolyte prepared according to Experimental Examples 1-2 to 1-4 of the present application.
11 is XRD analysis results of solid electrolytes, bacterial cellulose, general bacterial cellulose, and cellulose prepared according to Experimental Examples 1-4 to 1-7 of the present application.
12 is FT-IR analysis results for solid electrolytes, bacterial cellulose, and general bacterial cellulose prepared according to Experimental Examples 1-4 to 1-6 of the present application.
13 is a SEM photograph of a solid electrolyte prepared according to Experimental Examples 1-4 of the present application.
14 is TGA and DSC analysis results of solid electrolytes prepared according to Experimental Examples 1-4 of the present application.
15 to 18 are XPS analysis result graphs of solid electrolyte and bacterial cellulose according to Experimental Examples 1-4 and 1-5 of the present application.
19 is a graph measuring various ion transmission rates of solid electrolytes according to Experimental Examples 1-4 of the present application.
20 is a measurement of ion conductivity according to temperature of solid electrolytes according to Experimental Examples 2-1 to 2-5 of the present application.
21 is a graph analyzing element ratios of solid electrolytes according to Experimental Examples 3-1 to 3-5 of the present application and bacterial cellulose according to Experimental Examples 1-5.
22 is a result of analyzing the composition ratio of C1s spectra of the solid electrolyte according to Experimental Examples 3-1 to 3-5 of the present application and the bacterial cellulose according to Experimental Examples 1-5.
23 is a result of analyzing composition ratios of N 1s spectra of solid electrolytes according to Experimental Examples 3-1 to 3-5 of the present application and bacterial cellulose according to Experimental Examples 1-5.
24 is an XRD analysis result of solid electrolytes according to Experimental Examples 3-1 to 3-5, chitosan according to Experimental Examples 3-6, and bacterial cellulose according to Experimental Examples 1-5 of the present application.
25 is a solid electrolyte according to Experimental Examples 3-1 to 3-5 of the present application, chitosan according to Experimental Examples 3-6, bacterial cellulose according to Experimental Examples 1-5, and normal electrolytes according to Experimental Examples 1-6 It is a measurement of the ionic conductivity of bacterial cellulose as a function of temperature.
26 is a solid electrolyte according to Experimental Examples 3-1 to 3-5, chitosan according to Experimental Examples 3-6, bacterial cellulose according to Experimental Examples 1-5, and normal electrolytes according to Experimental Examples 1-6 of the present application. It is a measurement of the swelling rate according to the temperature of bacterial cellulose.
27 is a solid electrolyte according to Experimental Examples 3-1 to 3-5 of the present application, chitosan according to Experimental Examples 3-6, bacterial cellulose according to Experimental Examples 1-5, and normal electrolytes according to Experimental Examples 1-6 The moisture impregnation rate according to the temperature of bacterial cellulose was measured.
28 is a graph for explaining a change in charge/discharge characteristics according to external temperature conditions of a metal-air battery including a solid electrolyte according to Experimental Examples 1-4 of the present application.
FIG. 29 is a diagram for explaining retention characteristics according to the number of charge/discharge cycles in a low temperature and high temperature environment of a metal-air battery including a solid electrolyte according to Experimental Examples 1 to 4 of the present application.
30 are graphs for explaining charge/discharge characteristics according to external temperature of metal-air batteries including solid electrolytes according to Experimental Examples 1-4 of the present application.
31 are graphs for explaining capacity characteristics according to external temperature of metal-air batteries including solid electrolytes according to Experimental Examples 1-4 of the present application.
32 are graphs for explaining a change in charge/discharge characteristics according to a charge/discharge cycle according to an external temperature of a metal-air battery including a solid electrolyte according to Experimental Examples 1 to 4 of the present application.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the technical spirit of the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed content will be thorough and complete, and the spirit of the present invention will be sufficiently conveyed to those skilled in the art.

In this specification, when an element is referred to as being on another element, it means that it may be directly formed on the other element or a third element may be interposed therebetween. Also, in the drawings, the thicknesses of films and regions are exaggerated for effective explanation of technical content.

In addition, although terms such as first, second, and third are used to describe various elements in various embodiments of the present specification, these elements should not be limited by these terms. These terms are only used to distinguish one component from another. Therefore, what is referred to as a first element in one embodiment may be referred to as a second element in another embodiment. Each embodiment described and illustrated herein also includes its complementary embodiments. In addition, in this specification, 'and/or' is used to mean including at least one of the elements listed before and after.

In the specification, expressions in the singular number include plural expressions unless the context clearly dictates otherwise. In addition, the terms "comprise" or "having" are intended to designate that the features, numbers, steps, components, or combinations thereof described in the specification exist, but one or more other features, numbers, steps, or components. It should not be construed as excluding the possibility of the presence or addition of elements or combinations thereof. In addition, in the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted.

1 is a view showing a base composite fiber according to an embodiment of the present application, FIG. 2 is a view showing a first composite fiber according to an embodiment of the present application, and FIG. 3 is a view showing a first composite fiber according to an embodiment of the present application. 2 is a view showing composite fibers, and FIG. 4 is a view showing a solid electrolyte including base composite fibers according to an embodiment of the present application.

1 to 4, a base composite fiber 110 including cellulose 112 and chitosan 114 bonded to each other is provided. A plurality of the base composite fibers 110 may be provided in the form of a membrane M by forming a network with each other, and as shown in FIG. 4, the solid electrolyte according to the embodiment of the present application includes a plurality of the base composite fibers ( 110) may be provided in the form of the membrane (M) forming a network with each other. Due to this, the solid electrolyte may be provided with a plurality of pores therein, may have a high surface area, and may have excellent flexibility and mechanical properties.

According to one embodiment, the cellulose 112 may be bacterial cellulose.

When the solid electrolyte is installed in the metal-air battery, the metal-air battery can smoothly charge and discharge from -20°C to 80°C. That is, the metal-air battery including the solid electrolyte according to an embodiment of the present application operates smoothly at low and high temperatures, has a wide operating temperature range, and can be used in various environments.

The solid electrolyte may be in a state in which a crystalline phase and an amorphous phase are mixed. More specifically, in the solid electrolyte, the ratio of the amorphous phase may be higher than the ratio of the crystalline phase. Accordingly, the solid electrolyte may have high ion mobility.

In addition, the chitosan 114 may be chemically bonded to the cellulose 112 . Accordingly, in the cellulose 112 to which the chitosan 114 is bonded, stretching vibration corresponding to C-N may be observed during XPS analysis.

According to an embodiment, the solid electrolyte may include a first composite fiber 110a and a second composite fiber 110b. The first composite fiber 110a and the second composite fiber 110b may be manufactured from the base composite fiber 110 .

According to an embodiment, the surface of the cellulose 112 to which the chitosan 114 is bonded, that is, the surface of the base composite fiber 110 is oxidized using an oxidizing agent to produce the first composite fiber 110a. can

Specifically, the step of preparing the first composite fiber 110a includes preparing a source solution by adding the base composite fiber 110 to an aqueous solution containing an oxidizing agent, adjusting the pH of the source solution to basic Steps, adjusting the pH of the source solution to neutral, and washing and drying the pulp in the source solution to prepare the first conjugate fibers 110a may be included.

For example, the aqueous solution containing the oxidizing agent may be a TEMPO aqueous solution. Alternatively, for another example, the aqueous solution containing the oxidizing agent is 4-Hydroxy-TEMPO, (Diacetoxyiodo)benzene, 4-Amino-TEMPO, 4-Carboxy-TEMPO, 4-Methoxy-TEMPO, TEMPO methacrylate, 4-Acetamido -TEMPO, 3-Carboxy-PROXYL, 4-Maleimido-TEMPO, 4-Hydroxy-TEMPO benzoate, or 4-Phosphonooxy-TEMPO may include at least one.

The source solution may further include a sacrificial reagent and an additional oxidizing agent for the oxidation reaction of the base composite fiber 110 . For example, the sacrificial reagent may include at least one of NaBr, sodium iodide, sodium bromate, sodium bromite, sodium borate, sodium chlorite, or sodium chloride, and the additional oxidizing agent may include NaClO, potassium hypochlorite, or lithium It may include at least one of hypochlorite, sodium chlorite, sodium chlorate, Perchloric acid, Potassium perchlorate, Lithium perchlorate, Tetrabutylammonium perchlorate, Zinc perchlorate, hydrogen peroxide, or sodium peroxide.

According to one embodiment, in the step of adjusting the pH of the source solution to basic, the pH of the source solution may be adjusted to 10. Accordingly, the oxidation reaction can be easily induced while minimizing the precipitate, and the degree of oxidation of the first composite fiber 110a can be improved compared to the reaction condition of pH 8-9.

According to one embodiment, after the base composite fiber 110 and the sacrificial reagent are provided in an aqueous solution containing the oxidizing agent, the additional oxidizing agent may be provided. In addition, the additional oxidizing agent may be provided dropwise. Accordingly, rapid oxidation of the base composite fiber 110 can be prevented, and as a result, the surface of the base composite fiber 110 can be uniformly and stably oxidized.

In addition, according to one embodiment, bromine is bonded to the surface of the cellulose 112 to which the chitosan 114 is bonded, and the first functional group 116 containing nitrogen is substituted with bromine, thereby forming the second composite fiber (110b) can be made.

The first functional group 116 may be represented by <Formula 1> below, and the first functional group 116 may be combined with the chitosan 114 and/or the cellulose 112 .

<Formula 1>

That is, the second composite fiber 110b may have quaternary N.

Specifically, the step of preparing the second composite fiber 110b includes dispersing the base composite fiber 110 in a first solvent and adding a bromine source to prepare a first source solution, the first source solution adding a coupling agent to and reacting to prepare a reaction suspension, filtering, washing and freeze-drying the reaction suspension to prepare brominated base composite fibers, dispersing the brominated base composite fibers in a second solvent to prepare a reaction suspension 2 preparing a source solution, adding the precursor of the first functional group 116 to the second source solution and reacting, filtering, washing, and freeze-drying the reacted solution to form the second composite fiber 110b It may include the step of preparing.

For example, the first solvent and the second solvent may be the same as each other, and may include at least one of N, N-dimethylacetamide, Acetamide, Acetonitrile, ethanol, ethylenediamine, diethyl ether, or benzaldehyde.

For example, the bromine source may include at least one of LiBr, sodium bromide, or potassium bromide.

For example, the coupling agent may include N-bromosuccinimide and triphenylphosphine. Bromine can be easily bonded to the surface of the base composite fiber 110 by the coupling agent. Specifically, bromine in N-bromosuccinimide is combined with the base composite fiber 110, and triphenylphosphine can improve the reaction rate by reducing a bromine precursor (bromine source or N-bromosuccinimide).

As described above, after obtaining the brominated base composite fibers in the reaction suspension, the brominated base composite fibers may be freeze-dried. Accordingly, loss of bromine in the brominated base composite fiber can be minimized, and secondary reactions of bromine with other elements can be minimized.

For example, the precursor of the first functional group 116 may include 1,4-Diazabicyclo[2.2.2]octane.

According to an embodiment, the solid electrolyte may be manufactured by a gelatin process using the first composite fiber 110a and the second composite fiber 110b. In this case, the solid electrolyte includes the first composite fiber 110a and the second composite fiber 110b, and the first composite fiber 110a and the second composite fiber 110b are cross-linked to each other. It can be. The number of OH ions in the solid electrolyte may increase, ionic conductivity may be improved, negative charge density may be increased, and swelling resistance may be improved by the first composite fiber 110a. In addition, by the second composite fiber 110b, the molecular weight is increased to improve thermal stability, and the ion exchange capacity is improved to have a high water impregnation rate and high swelling resistance, and the first The composite fiber 110a and cross-linking ability may be improved, and selectively high solubility (ion discerning selectivity) in a specific solvent may be obtained. Accordingly, charge/discharge characteristics and lifespan characteristics of the secondary battery including the solid electrolyte may be improved.

Specifically, preparing the solid electrolyte may include preparing a mixed solution by mixing the first composite fiber 110a and the second composite fiber 110b in a solvent, and adding a crosslinking agent and an initiator to the mixed solution. and reacting to prepare a suspension, casting the suspension on a substrate and drying it to prepare a composite fiber membrane, and performing an ion exchange process on the composite fiber membrane.

For example, the solvent may include a mixed solvent of methylene chloride, 1,2-propanediol, and acetone, the crosslinker may include glutaraldehyde, and the initiator may include N,N-Diethyl-N-methyl -N-(2-methoxyethyl)ammonium bis(trifluoromethanesulfonyl)imide.

Also, for example, the ion exchange process for the composite fibrous membrane may include providing a KOH aqueous solution and a ZnTFSI aqueous solution to the composite fibrous membrane. Due to this, the OH ion content in the solid electrolyte may be improved.

As described above, according to an embodiment of the present application, the solid electrolyte includes at least one of the base composite fiber 110, the first composite fiber 110a, and the second composite fiber 110b. It may include the membrane (M) to.

In the solid electrolyte, the ratio of the chitosan 114 can be easily controlled according to the content of the chitosan derivative provided in the culture medium. Depending on the ratio of the chitosan 114, crystallinity, ion conductivity, and swelling ratio of the solid electrolyte may be controlled. Specifically, as the proportion of the chitosan 114 increases, the crystallinity of the solid electrolyte may gradually decrease.

According to one embodiment, the content of the chitosan 114 may be greater than 30 wt% and less than 70 wt%. If the content of the chitosan 114 is 30wt% or less or 70wt% or more, the ionic conductivity of the solid electrolyte is significantly reduced and the swelling ratio may be significantly increased.

However, according to an embodiment of the present application, the proportion of the chitosan 114 in the solid electrolyte may be greater than 30 wt% and less than 70 wt%, and as a result, the solid electrolyte maintains high ionic conductivity and has low swelling. It can have a ratio value.

5 is a diagram illustrating a metal-air battery including a solid electrolyte according to an embodiment of the present application.

Referring to FIG. 5 , a metal-air battery according to an embodiment of the present application is provided. The metal-air battery may include a negative electrode 200, a positive electrode 300, and a solid electrolyte 100 between the negative electrode 200 and the positive electrode 300.

The solid electrolyte 100 includes at least one of the base composite fiber 110, the first composite fiber 110a, and the second composite fiber 110b described with reference to FIGS. 1 to 4 It may be provided in the form of a membrane containing

The negative electrode 200 may include zinc. Alternatively, the negative electrode 200 may include lithium.

According to one embodiment, the anode 300 may include Pt/C and RuO2. Alternatively, according to another embodiment, the anode 300 may include a compound structure of a transition metal (eg, copper), phosphorus, and a chalcogen element (eg, sulfur). In this case, the compound structure may be provided in a form in which a plurality of fibrillated fibers constitute a membrane, and may have a (101) crystal plane. A specific manufacturing process of the compound structure will be described later.

The solid electrolyte 100 included in the metal-air battery according to the embodiment of the present application can maintain a stable state in a wide temperature range, and as a result, the metal-air battery including the solid electrolyte 100 It can be operated stably in various environments. In addition, the solid electrolyte 100 may contain a large amount of OH ions and moisture and may have high ion conductivity, thereby improving the charge/discharge capacity and lifespan characteristics of the metal air battery, as well as the metal air Growth of dendrites on the surface of the negative electrode 200 during the charging and discharging process of the battery can be minimized.

Hereinafter, a method for manufacturing a base composite fiber, a first composite fiber, a second composite fiber, and a solid electrolyte according to specific experimental examples of the present application will be described.

6 is a view for explaining a first composite fiber and a manufacturing method thereof according to Experimental Examples 1-2 of the present application, and FIG. 7 is a view illustrating a second composite fiber and a manufacturing method thereof according to Experimental Examples 1-3 of the present application. FIG. 8 is a view for explaining a method of manufacturing a solid electrolyte according to Experimental Examples 1-4 of the present application, and FIG. 9 is an ion movement principle of the solid electrolyte according to Experimental Examples 1-4 of the present application. It is a drawing for explaining.

Preparation of base composite fiber (CBC) according to Experimental Example 1-1

Acetobacter xylinum was prepared as a bacterial strain, and chitosan derivatives were prepared. Chitosan derivatives are prepared by dissolving 1 g of chitosan chloride in 1% (v/v) aqueous acetic acid with 1 M glycidyltrimethylammonium chloride for 24 hours at 65° C. in N ₂ atmosphere. After treatment for a while, precipitated and prepared by filtering with ethanol several times.

Pineapple juice (2% w/v), yeast (0.5% w/v), peptone (0.5% w/v), disodium phosphate (0.27% w/v), citric acid (0.015% w/v), and Hestrin-Schramm (HS) culture medium containing chitosan derivatives (2% w/v) was prepared and steam sterilized at 121° C. for 20 minutes. In addition, Acetobacter xylinum was activated in a pre-cultivation Hestrin-Schramm (HS) culture medium at 30 °C for 24 hours, and then maintained at pH 6 by adding acetic acid.

Then, Acetobacter xylinum was cultured in Hestrin-Schramm (HS) culture medium at 30 °C for 7 days.

The harvested bacterial pellicles were washed with deionized water to neutralize the pH of the supernatant and dehydrated in vacuum at 105 °C. The resulting cellulose was demineralized with 1 N HCl for 30 minutes (mass ratio 1:15, w/v) to remove excess reagent, and then washed several times with deionized water until the supernatant reached a neutral pH. It was purified by centrifugation. Finally, after evaporating all solvents at 100 °C, a base composite fiber (chitosan-bacterial cellulose (CBC)) was prepared.

Preparation of a first composite fiber (oCBC) according to Experimental Examples 1-2

The first composite fiber (TEMPO-oxidized CBC (oCBCs)) in which the surface of the base composite fiber is oxidized is, as shown in FIG. 6, 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO), Conjugation of hydroxymethyl and ortho-para directing acetamido base composite fibers (CBC) to the oxide of TEMPO by an oxidation reaction using sodium bromide (NaBr) and sodium hypochlorite (NaClO) designed in a way

Specifically, 2 g of base composite fiber fibers dispersed in 2 mM TEMPO aqueous solution were reacted with NaBr (1.9 mM). 5 mM NaClO was used as an additional oxidizing agent.

The reaction suspension was stirred by ultrasonic waves, and the reaction was allowed to proceed at room temperature for 3 hours. The pH of the suspension was maintained at 10 by successive additions of 0.5M NaOH solution. 1N HCl was then added to the suspension to keep the pH neutral for 3 hours. The resulting oxidized pulp in suspension was washed three times with 0.5 N HCl and the supernatant was brought to neutral pH with deionized water.

The washed pulp was exchanged with acetone, toluene for 30 minutes and dried to evaporate the solvent, and finally, a first conjugate fiber (oCBC) fiber was obtained.

As can be seen in FIG. 6 , the surface of the base composite fiber may be oxidized.

Preparation of the second composite fiber (qCBC) according to Experimental Examples 1-3

As shown in FIG. 7, the second composite (Covalently quaternized CBC (qCBC)) in which the first functional group having nitrogen is bonded to the base composite fiber is a coupling agent using 1,4-Diazabicyclo[2.2.2]octane It was prepared by conjugation of brominated base composite fibers (CBC) and quaternary amine groups by

Specifically, 1 g of the base composite fibers dispersed in a solution of N, N-dimethylacetamide (35 ml) was reacted with a suspension of LiBr (1.25 g) while stirring for 30 minutes. N-bromosuccinimide (2.1 g) and triphenylphosphine (3.2 g) were used as coupling agents. Both reaction mixtures were stirred for 10 minutes and reacted at 80° C. for 60 minutes.

The reaction suspension was then cooled to room temperature, added to deionized water, filtered, rinsed with deionized water and ethanol, and lyophilized to obtain brominated base composite fiber (bCBC) fibers.

Brominated base composite fibers were dissolved in 100 ml of N,N-dimethylformamide and reacted with 1.2 g of 1,4-Diazabicyclo[2.2.2]octane.

Thereafter, the mixture was sonicated for 30 minutes and reacted at room temperature for 24 hours. The resulting solution was mixed with diethyl ether, washed 5 times with diethyl ether/ethyl acetate, and freeze-dried to obtain a second composite fiber (covalently quaternized CBC (qCBC)).

As can be seen in FIG. 7 , it can be confirmed that the first functional group having nitrogen is bonded to the surface of the base composite fiber.

Preparation of solid electrolytes (CBCs) according to Experimental Examples 1-4

As shown in FIG. 8 , the solid electrolyte was prepared by a gelatin process using the first composite fiber (oCBC) and the second composite fiber (qCBC). Specifically, a mixture of methylene chloride, 1,2-propanediol and acetone (8: 1: 1 v / v /v%), and 1wt% of glutaraldehyde as a crosslinking agent and 0.3wt% of N,N-Diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethanesulfonyl)imide as an initiator were added.

The gel suspension was debubbled using a vacuum chamber (200 Pa) and cast on glass at 60° C. for 6 hours. The composite fibrous membrane was peeled off while coagulating with deionized water, rinsed with deionized water, and vacuum dried.

Solid electrolytes (CBCs) were prepared by ion exchange with 1 M KOH aqueous solution and 0.1 M ZnTFSI at room temperature for 6 hours, respectively. Thereafter, washing and soaking processes were performed with deionized water in an N ₂ atmosphere to avoid reaction with CO ₂ and formation of carbonate.

As can be seen in FIG. 8 , it can be seen that the first composite fiber (oCBC) and the second composite fiber (qCBC) are cross-linked to form the solid electrolytes (CBCs).

In addition, referring to FIG. 9, on the surfaces of the first composite fibers (oCBC) and the second composite fibers (qCBC) crosslinked of the solid electrolytes (CBCs), OH ions hop (grotthuss transport) )), and may move through diffusion in the interior spaced apart from the surface of the first composite fiber and the second composite fiber. In addition, the solid electrolytes (CBCs) may have an amorphous phase, as will be described later with reference to FIG. 11 , and due to this, they may have higher ion conductivity compared to a crystalline structure.

Preparation of bacterial cellulose according to Experimental Examples 1-5

In the method for preparing the base composite fiber of Experimental Example 1-1 described above, the chitosan derivative was omitted and the desalting process was omitted, thereby preparing bacterial cellulose not containing chitosan.

Preparation of general bacterial cellulose according to Experimental Examples 1-6

Using a culture medium containing glucose (2wt%), peptone (0.5wt%), yeast (0.5wt%), disodium phosphate (0.2wt%), and citric acid (0.1wt%), omitting the chitosan derivative , Bacterial cellulose was prepared in the same manner as in Experimental Example 1-1, omitting the desalting process.

Cellulose production according to Experimental Examples 1-7

Sugar cane bagasse was prepared, and a solvent was prepared by mixing ethanol, deionized water, NaOH, and nitric acid. After washing by dispersing sugarcane bagasse in the solvent, it was filtered and washed multiple times with deionized water until neutral pH.

The washed sugar cane bagasse was dried at 100° C. for 3 hours and ground with a stainless steel sieve of a 16 mesh IKA MF-10 mill to make fiber pulp.

The unit process of bleaching fiber pulp with hydrogen peroxide (1%, pH 13.5) for 1 hour at 55 °C was repeated three times in total, and the residue was removed with NaOH solution for 3 hours in an air atmosphere, followed by washing with ethanol and acetone. and dried at 50 °C for 6 hours to prepare cellulose.

Experimental Example 1-1 to Experimental Example 1-7 can be organized as shown in [Table 1] below.

division structure Experimental Example 1-1 Base Composite Fiber (CBC): Chitosan + Bacterial Cellulose Experimental example 1-2 First composite fiber (oCBC): surface oxidized chitosan + surface oxidized bacterial cellulose Experimental Example 1-3 Second composite fiber (qCBC): chitosan having a first functional group + bacterial cellulose having a first functional group Experimental Example 1-4 Crosslinking of the first conjugate fiber (oCBC) and the second conjugate fiber (qCBC) Experimental Example 1-5 Bacterial cellulose without chitosan Experimental Example 1-6 normal bacterial cellulose Experimental Example 1-7 cellulose

10 is a hydrogen NMR analysis result of the first composite fiber, the second composite fiber, and the solid electrolyte prepared according to Experimental Examples 1-2 to 1-4 of the present application.

Referring to FIG. 10 , hydrogen NMR was analyzed for the first composite fiber, the second composite fiber, and the solid electrolyte prepared according to Experimental Examples 1-2 to 1-4 described above.

Circles having colors in the analysis result of FIG. 10 correspond to hydrogen atoms corresponding to circles having the same color in FIG. 8 . That is, the NMR analysis result of the colored circles in FIG. 8 can be confirmed in FIG. 10 . As can be seen in FIG. 10 , it can be seen that the first composite fiber and the second composite fiber are alternately and repeatedly cross-linked at the same ratio.

11 is XRD analysis results of solid electrolytes, bacterial cellulose, general bacterial cellulose, and cellulose prepared according to Experimental Examples 1-4 to 1-7 of the present application.

Referring to FIG. 11 , XRD analysis was performed on the solid electrolyte, bacterial cellulose, general bacterial cellulose, and cellulose prepared according to Experimental Examples 1-4 to 1-7 described above.

As can be seen in FIG. 11, it can be seen that the cellulose fibers of Experimental Examples 1-7 have high crystallinity, and have peak values corresponding to (200), (110), and (1-10) crystal planes, resulting in hexagonal crystals. structure can be seen. On the other hand, it can be seen that the crystallinity of the bacterial cellulose of Experimental Examples 1-6 was relatively reduced, and the 2θ value of the peak corresponding to the (200) crystal plane decreased.

The crystallinity of the bacterial cellulose of Experimental Examples 1-5 prepared according to the examples of the present application was significantly reduced compared to the normal cellulose fibers of Experimental Examples 1-7, and the normal cellulose fibers and experiments of Experimental Examples 1-7 Unlike the general bacterial cellulose of Examples 1-6, it can be seen that it has peak values corresponding to the (020) and (110) crystal planes, and it can be confirmed that it has two peak values corresponding to the (1-10) crystal plane. . In addition, it can be confirmed that the peak value corresponding to the (110) crystal plane is higher than the peak value corresponding to other crystal planes (eg, (101), (1-10)).

In addition, it can be seen that the solid electrolytes of Experimental Examples 1-4 prepared according to the embodiments of the present application simultaneously have a crystalline phase and an amorphous phase, but the ratio of the amorphous phase is remarkably high.

12 is a FT-IR analysis result for solid electrolytes, bacterial cellulose, and general bacterial cellulose prepared according to Experimental Examples 1-4 to 1-6 of the present application.

Referring to FIG. 12 , FT-IR analysis was performed on the solid electrolyte, bacterial cellulose, and general bacterial cellulose according to Experimental Examples 1-4 to 1-6 described above.

As can be seen in FIG. 12, compared to the general bacterial cellulose of Experimental Example 1-6, in the case of the bacterial cellulose of Experimental Example 1-5, the stretching vibrations of CO and OH are 1056 cm ^-1 and 2932 cm ^-1 It can be seen that it has moved to 1022 cm ^-1 and 2895 cm ^-1 in . In addition, in the case of the solid electrolyte of Experimental Examples 1-4 according to an embodiment of the present application, CN ⁺ stretching vibration was observed at 1458 cm ⁻¹ , confirming that a quaternization reaction occurred. The vibrations at 2916 cm ^-1 and 3320 cm ^-1 correspond to OH stretching vibrations, and 1652 cm ^-1 and 1750 cm ^-1 correspond to water, and it can be confirmed that sufficient water molecules exist in the amorphous solid electrolyte, Experimental Example 1 The increase in the strength of the stretching vibration of CO in the -4 solid electrolyte is due to the reaction between chitosan and bacterial cellulose. In addition, it can be confirmed that carbonate is not substantially present in the solid electrolytes of Experimental Examples 1-4, and accordingly, it can be seen that it has advantages compared to commercially available PVA electrolytes.

13 is a SEM photograph of a solid electrolyte prepared according to Experimental Examples 1-4 of the present application.

Referring to FIG. 13 , SEM pictures of the solid electrolyte prepared according to Experimental Examples 1-4 were taken.

As can be seen in FIG. 13, it can be confirmed that a plurality of pores are present therein, and it can be confirmed that the bacterial cellulose fiber to which chitosan is bound is provided in a fibrillated form and has a diameter of 5 to 10 nm.

The measured pore size is about 20 to 200 nm, and it can be seen that chitosan-coupled bacterial cellulose fibers form a network with high pores and high surface area in the solid electrolyte, and can have high strength against swelling.

14 is TGA and DSC analysis results of solid electrolytes prepared according to Experimental Examples 1-4 of the present application.

Referring to FIG. 14 , TGA and DSC analyzes were performed while increasing the temperature at 5° C./min in a nitrogen atmosphere for the solid electrolyte prepared according to Experimental Examples 1-4 described above.

As can be seen in FIG. 14, it can be confirmed that the solid electrolyte according to Experimental Examples 1-4 of the present application has thermal stability stably up to about 225 ° C. That is, it can be seen that the solid electrolyte prepared according to the embodiment of the present invention has high temperature stability.

15 to 18 are XPS analysis result graphs of solid electrolyte and bacterial cellulose according to Experimental Examples 1-4 and 1-5 of the present application.

15 to 18, XPS analysis was performed on the solid electrolyte and bacterial cellulose prepared according to Experimental Examples 1-4 and 1-5 described above. 16 is a C1s spectrum, FIG. 17 is a N1s spectrum, and FIG. 18 is an O1s spectrum.

In FIG. 16, 284.5eV, 285.9eV, 288eV, and 289.7eV correspond to C=C, C-N, C-O, and C-OH, respectively, and in FIG. 17, 399.9eV, 401.3eV, and 402.5eV are pyrrolic, respectively. corresponds to quaternary, and oxidized N.

15 to 18, compared to the bacterial cellulose of Experimental Example 1-5 in which chitosan was omitted, the solid electrolyte of Experimental Example 1-4 having the bacterial cellulose bound with chitosan showed pyrrolic acid in the N1s spectrum as a result of XPS analysis. , quaternary, and peak values corresponding to oxidized N.

19 is a graph measuring various ion transmission rates of solid electrolytes according to Experimental Examples 1-4 of the present application.

Referring to FIG. 19, ion transport rates for K ⁺ , Zn ²⁺ , OH ^- , TFSI ^- , and [Ch] ⁺ ions were calculated for the solid electrolyte prepared according to Experimental Examples 1-4 described above. As shown in FIG. 19, it was confirmed to have the highest transmission rate for OH ^- ions, and it was confirmed to have the highest transmission rate for K ⁺ ions next to OH ^- ions.

Specific ionic conductivity is shown in [Table 2] below.

ion type Charge valence
(Z _i ) ionic conductivity
(m ² s ^-1 V ^-1 ) density
(M) shift factor
(t _i ) K ⁺ One 6.88* ^10-8 6 0.15 Zn ²⁺ 2 5.32* ^10-8 0.2 0.014 ^OH- One 2.15* ^10-7 6 0.75 ^TFSI- One 3.69* ^10-8 0.4 0.006 [Ch] ⁺ One 7.56* ^10-8 One 0.08

Preparation of solid electrolytes according to Experimental Examples 2-1 to 2-5

A solid electrolyte was prepared in the same manner as in Experimental Example 1-4, but the ratio of the first composite fiber (oCBC) of Experimental Example 1-2 and the ratio of the second composite fiber (qCBC) of Experimental Example 1-3 were as follows. Solid electrolytes according to Experimental Examples 2-1 to 2-5 were prepared while adjusting as shown in [Table 3].

division 1st composite fiber Second composite fiber Experimental Example 2-1 10wt% 90wt% Experimental Example 2-2 30wt% 70wt% Experimental Example 2-3 50wt% 50wt% Experimental Example 2-4 70wt% 30wt% Experimental Example 2-5 90wt% 10wt%

20 is a measurement of ion conductivity according to temperature of solid electrolytes according to Experimental Examples 2-1 to 2-5 of the present application.

Referring to FIG. 20, the ionic conductivity of the solid electrolytes according to Experimental Examples 2-1 to 2-5 described above was measured according to temperature, and the ionic conductivity of the commercially available A201 membrane was measured according to temperature and compared. did

As can be seen in FIG. 20 , as the temperature increased, the ionic conductivity of the solid electrolyte and the A201 membrane according to Experimental Examples 2-1 to 2-5 increased. In addition, it can be seen that the ionic conductivity of the solid electrolytes according to Experimental Examples 2-1 to 2-5 is significantly higher than that of the A201 membrane.

In addition, according to Experimental Example 2-3, the ionic conductivity of the solid electrolyte having the same ratio of the first composite fiber and the second composite fiber is It can be seen that it is significantly higher than that of the solid electrolytes according to Examples 2-5. As a result, controlling the ratio of the first composite fiber to more than 30wt% and less than 70wt% and controlling the ratio of the second composite fiber to less than 70wt% and more than 30wt% is an efficient method for improving the ionic conductivity of OH ions can confirm that it is

Solid electrolyte preparation according to Experimental Example 3-1 to Experimental Example 3-5

According to the above-described experimental example, base composite fibers were prepared, but base composite fibers having different chitosan contents were prepared by adjusting the addition ratio of the chitosan derivative. Thereafter, according to Experimental Examples 1-4 described above, solid electrolytes were prepared using base composite fibers having different chitosan contents.

Preparation of chitosan according to Experimental Examples 3-6

As a comparative example to Experimental Examples 3-1 to 3-5 described above, pure chitosan was prepared.

The content of chitosan in the solid electrolyte according to Experimental Example 3-1 to Experimental Example 3-6 is shown in [Table 4] below.

division Proportion of Chitosan Experimental Example 3-1 10wt% Experimental Example 3-2 30wt% Experimental Example 3-3 50wt% Experimental Example 3-4 70wt% Experimental Example 3-5 90wt% Experimental Example 3-6 100wt%

21 is a graph analyzing element ratios of solid electrolytes according to Experimental Examples 3-1 to 3-5 of the present application and bacterial cellulose according to Experimental Examples 1-5, and FIG. 22 is Experimental Example 3- of the present application. 1 to Experimental Examples 3-5 and solid electrolytes according to Experimental Examples 1-5 are results of analyzing the composition ratio of C1s spectra of bacterial cellulose according to Experimental Examples 3-1 to 3-5 of the present application. This is the result of analyzing the composition ratio of N1s spectra of the solid electrolyte and bacterial cellulose according to Experimental Examples 1-5.

21 to 23, XPS analysis is performed on the solid electrolyte according to Experimental Examples 3-1 to 3-5 described above and the bacterial cellulose in which chitosan is omitted according to Experimental Examples 1-5 described above, , As shown in FIG. 21, the ratio of elements in the solid electrolyte was analyzed, the composition ratio of C1s spectra was analyzed as shown in FIG. 22, and the composition ratio of N1s spectra was analyzed as shown in FIG. 23.

In the case of the solid electrolytes according to Experimental Examples 3-1 to 3-5, compared to the bacterial cellulose of Experimental Example 1-5 in which chitosan was omitted, C-N bonds were observed according to the bonding of chitosan and bacterial cellulose. there is.

In addition, as can be seen in FIG. 22, as the chitosan ratio increases from 0 to 50 wt%, the C-N ratio increases, and as the chitosan ratio increases from 50 wt% to 90 wt%, the C-N ratio decreases. It can be seen. In other words, when the ratio of chitosan is greater than 30wt% and less than 70wt%, it can be seen that the C-N ratio in the solid electrolyte is remarkably high.

In addition, as can be seen in FIG. 23, the nitrogen peak was not detected in the bacterial cellulose of Experimental Examples 1-5 in which chitosan was omitted, and as the ratio of chitosan increased, the ratio of oxidized N generally increased, but pyrrolic N It can be seen that the ratio of increases as the ratio of chitosan increases from 0 to 50wt%, and decreases as the ratio of chitosan increases from 50wt% to 90wt%. In other words, when the proportion of chitosan is greater than 30wt% and less than 70wt%, it can be seen that the proportion of pyrrolic N in the solid electrolyte is remarkably high.

In addition, as can be seen in FIG. 21, the nitrogen ratio increased as the chitosan ratio increased, and according to Experimental Examples 3-5, when the chitosan ratio was 90wt%, it was confirmed that the nitrogen ratio was 6.63at%.

24 is an XRD analysis result of solid electrolytes according to Experimental Examples 3-1 to 3-5, chitosan according to Experimental Examples 3-6, and bacterial cellulose according to Experimental Examples 1-5 of the present application.

Referring to FIG. 24, solid electrolytes according to Experimental Examples 3-1 to 3-5 described above, chitosan according to Experimental Examples 3-6, and bacterial cellulose omitting chitosan according to Experimental Examples 1-5 described above XRD analysis was performed for

As can be seen in FIG. 24, the chitosan of Experimental Example 3-6 itself did not observe a specific peak, and compared to the bacterial cellulose of Experimental Example 1-5), the solid according to Experimental Example 3-1 to Experimental Example 3-6 It can be seen that the electrolyte has somewhat low crystallinity.

In addition, as the proportion of chitosan gradually increases, it can be confirmed that the crystallinity decreases and has an amorphous phase like chitosan. In particular, according to Experimental Examples 3-4, when the proportion of chitosan is 70 wt% or more, It can be seen that there is a sharp decrease.

25 is a solid electrolyte according to Experimental Examples 3-1 to 3-5 of the present application, chitosan according to Experimental Examples 3-6, bacterial cellulose according to Experimental Examples 1-5, and normal electrolytes according to Experimental Examples 1-6 It is a measurement of the ionic conductivity of bacterial cellulose as a function of temperature.

Referring to FIG. 25, solid electrolytes according to Experimental Examples 3-1 to 3-5, chitosan according to Experimental Example 3-6, bacterial cellulose without chitosan according to Experimental Example 1-5, and Experimental Example 1- For normal bacterial cellulose according to 6, the ionic conductivity was measured as a function of temperature.

As can be seen in FIG. 25, as the temperature increases, the solid electrolyte of Experimental Examples 3-1 to 3-5, the chitosan of Experimental Example 3-6, the bacterial cellulose in which chitosan is omitted of Experimental Example 1-5, and the experiment The ionic conductivity of the normal bacterial cellulose of Examples 1-6 was increased. In addition, it can be confirmed that the bacterial cellulose according to Experimental Examples 1-5 of the present invention has higher ionic conductivity than the general bacterial cellulose of Experimental Examples 1-6 and chitosan of Experimental Examples 3-6, and Experimental Example 3 The ionic conductivity of the solid electrolytes according to -1 to Experimental Examples 3-5 was compared with the bacterial cellulose in which chitosan was omitted in Experimental Example 1-5, the normal bacterial cellulose in Experimental Example 1-6, and the chitosan in Experimental Example 3-6. , it can be confirmed that it is remarkably high.

In addition, the ionic conductivity of the solid electrolyte having 50wt% chitosan according to Experimental Example 3-3 is the solid electrolyte according to Experimental Example 3-1, Experimental Example 3-2, Experimental Example 3-4, and Experimental Example 3-5. It can be seen that it is significantly higher than the As a result, it can be confirmed that controlling the ratio of chitosan in the solid electrolyte to more than 30wt% and less than 70wt% is an efficient method for improving the ionic conductivity of OH ions.

26 is a solid electrolyte according to Experimental Examples 3-1 to 3-5, chitosan according to Experimental Examples 3-6, bacterial cellulose according to Experimental Examples 1-5, and normal electrolytes according to Experimental Examples 1-6 of the present application. It is a measurement of the swelling rate according to the temperature of bacterial cellulose.

Referring to FIG. 26, solid electrolytes according to Experimental Examples 3-1 to 3-5, chitosan according to Experimental Examples 3-6, bacterial cellulose according to Experimental Examples 1-5, and Experimental Examples 1-6 For normal bacterial cellulose, the swelling rate was measured as a function of temperature.

As can be seen in FIG. 26, as the temperature increases, the solid electrolyte according to Experimental Examples 3-1 to 3-5, the chitosan of Experimental Example 3-6, the bacterial cellulose omitting chitosan of Experimental Example 1-5, and The swelling rate of the general bacterial cellulose of Experimental Examples 1-6 increased. In addition, the bacterial cellulose according to Experimental Example 1-5 of the present application, the general bacterial cellulose of Experimental Example 1-6, and the chitosan of Experimental Example 3-6, as well as Experimental Example 3-1, Experimental Example 3-2, Experiment Compared to Example 3-4 and Experimental Example 3-5, it can be seen that it has a low swelling ratio.

In addition, the swelling ratio of the solid electrolyte having 50wt% chitosan according to Experimental Example 3-3, the solid according to Experimental Example 3-1, Experimental Example 3-2, Experimental Example 3-4, and Experimental Example 3-5 It can be seen that the electrolytes are significantly lower than those of the bacterial cellulose according to Experimental Examples 1-5 of the present application. As a result, it can be seen that controlling the proportion of chitosan in the solid electrolyte to greater than 30wt% and less than 70wt% is an effective method for reducing the swelling rate.

27 is a solid electrolyte according to Experimental Examples 3-1 to 3-5 of the present application, chitosan according to Experimental Examples 3-6, bacterial cellulose according to Experimental Examples 1-5, and normal electrolytes according to Experimental Examples 1-6 The moisture impregnation rate according to the temperature of bacterial cellulose was measured.

Referring to FIG. 27, solid electrolytes according to Experimental Examples 3-1 to 3-5, chitosan according to Experimental Examples 3-6, bacterial cellulose according to Experimental Examples 1-5, and Experimental Examples 1-6 Moisture impregnation was measured as a function of temperature for the general bacterial cellulose according to the method.

As can be seen in FIG. 27, as the temperature increases, the solid electrolyte according to Experimental Examples 3-1 to 3-5, the chitosan of Experimental Example 3-6, and the bacterial cellulose omitting chitosan of Experimental Example 1-5, the experiment The moisture impregnation rate of the general bacterial cellulose of Examples 1-6 was increased.

In the room temperature range, the water impregnation rate of the solid electrolyte having 50wt% chitosan according to Experimental Example 3-3, Experimental Example 3-1, Experimental Example 3-2, Experimental Example 3-4, and Experimental Example 3-5 It can be seen that the water impregnation rate is higher than that of the solid electrolyte as well as the bacterial cellulose without the chitosan of Experimental Examples 1-5, the normal bacterial cellulose of Experimental Examples 1-6, and the chitosan of Experimental Examples 3-6. As a result, it can be confirmed that controlling the proportion of chitosan in the solid electrolyte to more than 30wt% and less than 70wt% is an efficient method for improving the water impregnation rate.

Fabrication of a metal-air battery according to an experimental example

A metal-air battery was manufactured using the solid electrolyte according to Experimental Examples 1 to 4 described above, a positive electrode having a compound structure of copper, phosphorus, and sulfur, and a patterned zinc negative electrode.

An anode with a compound structure of copper, phosphorus, and sulfur was prepared in the following manner.

Three suspensions of ethanol/ethylenediamine were prepared, and dithiooxamide, tetradecylphosphonic acid/ifosfamide, and copper chloride were added, respectively, and stirred.

Then, the dithiooxamide solution and tetradecylphosphonic acid/ifosfamide were continuously and gradually injected into the copper chloride solution while stirring, and the mixture was stirred for 2 hours while adding ammonium hydroxide.

The resulting copper-dithiooxamide-tetradecylphosphonic acid-ifosfamide black suspension was refluxed at 120 °C for 6 h, collected by centrifugation, washed with deionized water and ethanol, and dried in vacuum.

Then, the obtained copper-dithiooxamide-tetradecylphosphonic acid-ifosfamide precursor suspension was mixed with deionized water and sodium bisulfite with Triton X-165 in an ice bath. The reaction suspension was autoclaved and cooled to room temperature. The obtained black solid sponge was washed with deionized water and ethanol until the supernatant had a neutral pH.

The resulting product was transferred to a -70 ° C environment for 2 hours, immersed in liquid nitrogen, and freeze-dried in vacuum to prepare a cathode material with a compound structure of copper, phosphorus and sulfur, and a cathode material (90 wt%), super P carbon (5wt%), and PTFE (5wt%) were mixed with N-methyl-pyrrolidone containing a 0.5wt% Nafion solution to prepare a slurry. The slurry was coated on a stainless steel mesh and the solvent was evaporated. Then, it was cut into a size of 6 cm x 1.5 cm and dried in a vacuum to prepare a positive electrode.

28 is a graph for explaining a change in charge/discharge characteristics according to external temperature conditions of a metal-air battery including a solid electrolyte according to Experimental Examples 1-4 of the present application.

Referring to FIG. 28, the external temperature of the metal-air battery using the solid electrolytes (CBCs), the copper, phosphorus, and sulfur compound structure positive electrode, and the patterned zinc negative electrode according to Experimental Examples 1 to 4 described above was set at -20 ° C. Changes in charge and discharge characteristics were measured while changing up to 80 ° C. In (b) of FIG. 28, the current density is measured at 25 mAcm ^-2 .

As can be seen in FIG. 28, it can be seen that the voltage value increases as the temperature increases and has a low overpotential. That is, it can be confirmed that the secondary battery including the solid electrolyte according to Experimental Examples 1-4 of the present application can be stably driven in high and low temperature environments.

FIG. 29 is a diagram for explaining retention characteristics according to the number of charge/discharge cycles in a low temperature and high temperature environment of a metal-air battery including a solid electrolyte according to Experimental Examples 1 to 4 of the present application.

Referring to FIG. 29, for the metal-air battery using the solid electrolytes (CBCs), the positive electrode with a compound structure of copper, phosphorus, and sulfur, and the patterned zinc negative electrode according to Experimental Examples 1-4 described above, the external temperature was set to -20 ° C and Charge/discharge cycles were performed under the condition of 25 mAcm -2 while controlling the temperature to 80°C. In FIG. 29, the charge/discharge cycle was performed at -20°C in black, and the charge/discharge cycle in red in FIG. 29 was performed at 80°C.

As can be seen in FIG. 29 , it can be confirmed that the battery is stably driven while maintaining a high retention characteristic of about 94.5% even after 1,500 charge/discharge cycles at high and low temperatures.

30 are graphs for explaining charge/discharge characteristics according to external temperature of metal-air batteries including solid electrolytes according to Experimental Examples 1-4 of the present application.

Referring to FIG. 30, the external temperature of the metal-air battery using the solid electrolytes (CBCs), the positive electrode having a compound structure of copper, phosphorus, and sulfur, and the patterned zinc negative electrode according to Experimental Examples 1 to 4 described above is -20 ° C, 25 While controlling at °C and 80 °C, charge and discharge voltages were measured under the condition of 25 mAcm ^-2 , and a Nyquist plot was shown.

As can be seen from FIG. 30 , it can be seen that only a slight deterioration in characteristics is observed in a low-temperature environment, and stable operation is performed at low temperature, normal temperature, and high temperature.

31 are graphs for explaining capacity characteristics according to external temperature of metal-air batteries including solid electrolytes according to Experimental Examples 1-4 of the present application.

Referring to FIG. 31, the external temperature of the metal-air battery using the solid electrolytes (CBCs), the positive electrode having a compound structure of copper, phosphorus, and sulfur, and the patterned zinc negative electrode according to Experimental Examples 1 to 4 described above is set to -40 ° C to 105 ° C. Capacitance was measured under the condition of 25 mAcm ^-2 while controlling up to °C.

As can be seen in Figure 31, it can be seen that it has a high capacity of 1Ah or more in the range of -20 ℃ ~ 80 ℃. On the other hand, below -20 ° C, it can be seen that the mobility of OH ions in the solid electrolyte is rapidly lowered, and the capacity is rapidly lowered. You can check. Specifically, it was greatly reduced to 0.234Ah at -40 ° C, and significantly decreased to 0.394 Ah at 105 ° C.

32 are graphs for explaining a change in charge/discharge characteristics according to a charge/discharge cycle according to an external temperature of a metal-air battery including a solid electrolyte according to Experimental Examples 1 to 4 of the present application.

Referring to FIG. 32, the external temperature of the metal-air battery using the solid electrolytes (CBCs), the positive electrode having a compound structure of copper, phosphorus, and sulfur, and the patterned zinc negative electrode according to Experimental Examples 1 to 4 described above was -20 ° C and 80 ° C. 1,500 charge/discharge cycles were performed for 200 hours under conditions of 25 mAcm ^-2 while controlling at °C. 32 (a) shows the result of charging and discharging at -20°C, and (b) of FIG. 32 shows the result of charging and discharging at 80°C.

As can be seen in FIG. 32, although the charge and discharge characteristics are slightly deteriorated in a low temperature environment of -20 ° C, it can be confirmed that they are stably driven for a long time, and it can be confirmed that they are stably driven for a long time even in a high temperature environment of 80 ° C. .

In the above, the present invention has been described in detail using preferred embodiments, but the scope of the present invention is not limited to specific embodiments, and should be interpreted according to the appended claims. In addition, those skilled in the art should understand that many modifications and variations are possible without departing from the scope of the present invention.

100: solid electrolyte
110: base composite fiber
110a: first composite fiber
110b: second composite fiber
112: cellulose
114: chitosan
116 first functional group
200: cathode
300: anode

Claims (12)

In the solid electrolyte in which a plurality of base composite fibers form a network,
The base composite fibers include cellulose and chitosan bonded to each other,
When the solid electrolyte is mounted in a metal air battery, the solid electrolyte comprising operating the metal air battery from -20 ° C to 80 ° C.
According to claim 1,
The cellulose is a solid electrolyte comprising bacterial cellulose.
According to claim 1,
a first composite fiber in which the surface of the base composite fiber is oxidized; and
A surface of the base composite fiber includes a second composite fiber bonded to a first functional group having nitrogen,
A solid electrolyte comprising a plurality of first composite fibers and a plurality of second composite fibers cross-linked to form a network.
According to claim 3,
The ratio of the first composite fiber is greater than 30wt% and less than 70wt%,
A solid electrolyte comprising a ratio of the second composite fiber is less than 70wt% and greater than 30wt%.
According to claim 1,
The metal-air battery is a solid electrolyte containing zinc as a negative electrode.
According to claim 1,
A solid electrolyte comprising controlling crystallinity, ion conductivity, and swelling ratio of the solid electrolyte according to the ratio of chitosan.
a cathode electrode using oxygen as a cathode active material;
A cathode electrode containing a metal; and
Including a solid electrolyte disposed between the positive electrode and the negative electrode,
The solid electrolyte includes a network formed of a plurality of base composite fibers,
A metal-air battery comprising operating at -20°C to 80°C.
According to claim 7,
A metal-air battery comprising an increase in discharge capacity as the temperature increases within -20 ° C to 80 ° C.
According to claim 7,
The cathode electrode contains zinc,
The positive electrode is a metal-air battery containing a compound containing a transition metal, phosphorus, and a chalcogen element.
According to claim 7,
The base composite fibers of the solid electrolyte include cellulose and chitosan bonded to each other,
A metal-air battery comprising a ratio of the chitosan in the solid electrolyte greater than 30wt% and less than 70wt%.
According to claim 10,
The solid electrolyte includes a first composite fiber in which the surface of the base composite fiber is oxidized, and a second composite fiber in which a surface of the base composite fiber is bonded with a first functional group having nitrogen, a metal-air battery,
According to claim 10,
The cellulose of the base composite fiber is a metal-air battery including bacterial cellulose.

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