KR20150091835A - Sea water secondary battery for manufacturing h_2 - Google Patents

Abstract

Provided are a secondary battery and a secondary battery system. The secondary battery for producing hydrogen comprises: a liquid cathode unit including a sodium-containing solution and a cathode current collector dipped in the sodium-containing solution; an anode unit including a liquid organic electrolyte, an anode current collector dipped in the liquid organic electrolyte, and an anode active material layer disposed on a surface of the anode current collector; a solid electrolyte disposed between the cathode unit and the anode unit; and a hydrogen discharging unit connected to the cathode unit, and withdrawing hydrogen generated from the cathode unit to the outside during discharge.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a hydrogen-

The present invention relates to a rechargeable secondary battery. More particularly, the present invention relates to a secondary battery capable of producing hydrogen in a charging / discharging process.

Generally, a secondary battery means a battery capable of charging and discharging through conversion between chemical energy and electric energy by using a material capable of electrochemically reacting with the positive electrode and the negative electrode. A representative example of such a battery is a lithium secondary battery that generates electrical energy by a change in chemical potential when the lithium ions are intercalated / deintercalated in the positive electrode and the negative electrode.

The lithium secondary battery is manufactured by using a material capable of reversible intercalation / deintercalation of lithium ions as a positive electrode and a negative electrode active material, and filling an organic electrolytic solution or a polymer electrolyte between the positive electrode and the negative electrode.

However, lithium exists only in a limited amount on the earth, and it is generally obtained through a difficult process from mineral, salt and the like. There is a problem that a high cost and a high energy are used for manufacturing a battery, and a next-generation secondary battery that can replace lithium is needed.

Much research has been conducted on a device for generating hydrogen for using hydrogen as a fuel separately from a secondary battery. For example, in the case of submarines and the like, they are operated in an environment rich in hydrogen, such as seawater, so that a technique of generating hydrogen in sea water is desperately required.

In the conventional case, the secondary battery and the hydrogen generator are separately developed and separately installed and used, and development of a technology for integrating and operating them into one apparatus is required.

The present invention provides a hydrogen-producing secondary battery that uses seawater instead of lithium and is capable of producing hydrogen from seawater.

According to an embodiment of the present invention, there is provided a lithium secondary battery comprising: a liquid anode including a sodium-containing solution and a cathode current collector impregnated with the sodium-containing solution; A negative electrode part including a liquid organic electrolyte, a negative electrode current collector impregnated in the liquid organic electrolyte, and a negative electrode active material layer positioned on the surface of the negative electrode current collector; A solid electrolyte positioned between the anode and the cathode; And a hydrogen discharging portion connected to the anode portion and discharging hydrogen generated at the anode portion to the outside during discharging.

The hydrogen discharge unit may include a gas pipe installed at an upper end of the anode unit containing the sodium-containing solution to selectively open and close the battery when the battery is discharged or after completion of discharge to discharge hydrogen.

The anode portion may have an inlet portion of the sodium-containing solution and an outlet portion of the sodium-containing solution on one side.

The organic electrolyte in the cathode portion may include a non-aqueous organic solvent and / or a sodium salt.

The non-aqueous organic solvent may be a carbonate-based, ester-based, ether-based, ketone-based, alcohol-based, aprotic solvent or a combination thereof.

The sodium salt is _{NaClO 4, NaPF 4, NaPF 6} , NaAsF 6, may be NaTFSI, Na Beti (NaN [SO 2 C 2 F 5] 2) or a combination thereof.

The negative electrode active material layer positioned on the surface of the negative electrode collector may include a negative electrode active material, a conductive material, and / or a binder, and the negative electrode active material may include a carbon-based material and / or a sodium intercalation material.

The carbon-based material may be natural graphite, artificial graphite, soft carbon, hard carbon, or a combination thereof.

The sodium intercalation material may be selected from the group consisting of Li ₄ Ti ₅ O ₁₂ , NaCo ₂ O ₄ , Na ₂ Ti ₃ O ₇ , Fe ₃ O ₄ , TiO ₂ , Sb ₂ O ₄ , Sb / C composite, SnSb / C A composite, an amorphous P / C composite, or a combination thereof.

The conductive material may be a carbon-based material that is natural graphite, artificial graphite, carbon black, acetylene black, ketjen black, or carbon fiber; Copper, nickel, aluminum, or silver metal powder; Metal fiber; Conductive polymers; Or a mixture thereof.

The binder may be selected from the group consisting of polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, polymers comprising ethylene oxide, polyvinyl pyrrolidone, polyurethane, poly Polyvinylidene fluoride, polyethylene, polypropylene, styrene-butadiene rubber, acrylated styrene-butadiene rubber, epoxy resin, nylon, or a combination thereof.

The solid electrolyte may be an amorphous ion conductive material such as a phosphorus-based glass, an oxide / sulfide based glass, a Na superionic conductor (NASICON), a sodium sulfide based solid electrolyte, a sodium oxide based solid electrolyte, And combinations of these.

The cathode current collector may be carbon paper, carbon fiber, carbon cloth, carbon felt, metal thin film, or a combination thereof.

The porosity of the positive electrode collector may be 1 m to 250 m.

When the secondary battery is discharged, the following Reaction Schemes 1 and / or 2 may occur at the anode portion.

[Reaction Scheme 1]

Na ⁺ + H ₂ O + e ^- -> NaOH + 1 / 2H ₂

[Reaction Scheme 2]

Na ⁺ + 1 / 2H ₂ O + 1 / 4O ₂ + e ^- -> NaOH

When the secondary battery is charged, the following Reaction Schemes 3 and / or 4 may occur at the anode portion.

[Reaction Scheme 3]

NaCl -> Na + 1 / 2Cl ₂

[Reaction Scheme 4]

NaOH -> Na + 1 / 2H ₂ O + 1 / 4O ₂

The sodium-containing solution may be seawater.

According to the present embodiment, the secondary battery can be manufactured at a lower cost by using abundant and easy-to-acquire resources such as seawater.

In addition, it is possible to produce hydrogen from the seawater during the charging and discharging of the secondary battery, and it is possible to minimize the cost and the cost of the hydrogen production, which is the next generation energy source.

1 is a schematic view of a secondary battery according to an embodiment of the present invention.
2 is charge / discharge data of a secondary battery according to an embodiment of the present invention.
3 is cycle characteristic data of a secondary battery according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited thereto, and the present invention is only defined by the scope of the following claims.

In one embodiment of the present invention, there is provided a positive electrode comprising: a liquid positive electrode portion including a sodium containing solution and a positive electrode current collector impregnated in the sodium containing solution; A negative electrode part including a liquid organic electrolyte, a negative electrode current collector impregnated in the liquid organic electrolyte, and a negative electrode active material layer positioned on the surface of the negative electrode current collector; A solid electrolyte positioned between the anode and the cathode; And a hydrogen discharging portion connected to the anode portion and discharging hydrogen generated at the anode portion to the outside during discharging.

The hydrogen discharge unit is installed at the upper end of the anode unit containing the sodium-containing solution, and is selectively opened and closed at the time of battery discharge or completion of discharge to discharge hydrogen.

1 is a schematic view of a secondary battery according to an embodiment of the present invention. Fig. 1 is an embodiment of the present invention, and seawater is described as an example of a sodium-containing solution. Hereinafter, one embodiment of the present invention will be described with reference to FIG.

1 (a) shows a schematic principle of a secondary battery. From FIG. 1 (a), it can be seen that by using the potential difference according to the concentration of sodium ions in a sodium-containing solution (for example, seawater) It can be seen that the secondary battery according to the example is driven.

FIGS. 1 (b) and 1 (c) are schematic views and photographs showing charge / discharge experiments using a Na counter electrode as a negative electrode. 1 (d) and 1 (e) are schematic views showing chemical reactions during charging and discharging of a half cell using a Na counter electrode as a cathode. In this structure, the cathode may be replaced with a cathode of a new structure including the anode active material.

In a secondary battery according to an embodiment of the present invention, the following Reactions 1 and / or 2 may occur at the anode when discharging.

[Reaction Scheme 1]

Na ⁺ + H ₂ O + e ^- -> NaOH + 1 / 2H ₂

[Reaction Scheme 2]

Na ⁺ + 1 / 2H ₂ O + 1 / 4O ₂ + e ^- -> NaOH

Also, in the secondary battery according to an embodiment of the present invention, the following Reaction Schemes 3 and / or 4 may occur at the anode portion during charging.

[Reaction Scheme 3]

NaCl -> Na + 1 / 2Cl ₂

[Reaction Scheme 4]

NaOH -> Na + 1 / 2H ₂ O + 1 / 4O ₂

Additional reactions other than the above-described Reaction Schemes 1 to 3 may also occur, but the reaction that has a major influence on the driving of the secondary battery may be the above three reaction schemes.

Charging and discharging of the battery can be performed from the above reaction. This type of battery can be a next-generation alternative after lithium because it uses sodium as an energy source instead of lithium.

It is also expected that charge and discharge will be possible even with the use of human body fluids of similar composition to sodium-containing solutions (e.g., seawater). If this is the case, the application field can be extended to a wide variety.

On one side of the anode portion, the inflow portion of the sodium-containing solution and the outflow portion of the sodium-containing solution may be located. From this, a continuous supply of the sodium-containing solution in the anode part may be possible.

In the secondary battery, sodium is moved to the cathode portion and removed in the anode portion by a reaction formula occurring at the anode portion at the time of charging.

In the secondary battery, hydrogen (H ₂ ) is generated by a reaction formula occurring at the anode portion at the time of discharging. The hydrogen generated in the anode portion is drawn out through the hydrogen discharge portion.

In this embodiment, the hydrogen discharge unit may include a gas pipe installed at the upper end of the anode unit and selectively opened and closed.

Accordingly, hydrogen generated in the anode portion is moved upward in the anode tube, and can be drawn out to the outside through a gas pipe installed on the anode tube.

As described above, the secondary battery of the present embodiment supplies electric energy through charging and discharging, and can also produce hydrogen from the anode at the time of discharging and provide it to the outside.

The cathode portion may include an organic electrolyte, and the organic electrolyte in the cathode portion may include a non-aqueous organic solvent and / or a sodium salt.

The non-aqueous organic solvent serves as a medium through which ions involved in the electrochemical reaction of the battery can move.

As the non-aqueous organic solvent, a carbonate-based, ester-based, ether-based, ketone-based, alcohol-based or aprotic solvent may be used. Examples of the carbonate solvent include dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), methyl propyl carbonate (MPC), ethyl propyl carbonate (EPC), methyl ethyl carbonate (MEC) EC), propylene carbonate (PC), and butylene carbonate (BC) may be used. As the ester solvent, methyl acetate, ethyl acetate, n-propyl acetate, 1,1-dimethyl ethyl acetate, methyl propionate , Ethyl propionate,? -Butyrolactone, decanolide, valerolactone, mevalonolactone, caprolactone and the like can be used. Examples of the ether solvent include dibutyl ether, tetraglyme, diglyme, dimethoxyethane, 2-methyltetrahydrofuran, and tetrahydrofuran. As the ketone solvent, cyclohexanone may be used have. As the alcoholic solvent, ethyl alcohol, isopropyl alcohol and the like can be used. As the aprotic solvent, R-CN (R is a C2 to C20 linear, branched or cyclic hydrocarbon group, An amide such as nitriles such as dimethylformamide, and dioxolanes such as 1,3-dioxolane, sulfolanes, and the like can be used.

The non-aqueous organic solvent may be used alone or in admixture of one or more. If the non-aqueous organic solvent is used in combination, the mixing ratio may be appropriately adjusted according to the desired cell performance. .

In the case of the carbonate-based solvent, it is preferable to use a mixture of a cyclic carbonate and a chain carbonate. In this case, when the cyclic carbonate and the chain carbonate are mixed in a volume ratio of about 1: 1 to about 1: 9, the performance of the electrolytic solution may be excellent.

The non-aqueous organic solvent may further include the aromatic hydrocarbon-based organic solvent in the carbonate-based solvent. In this case, the carbonate-based solvent and the aromatic hydrocarbon-based organic solvent may be mixed in a volume ratio of about 1: 1 to about 30: 1.

The aromatic hydrocarbon-based organic solvent may be an aromatic hydrocarbon-based compound represented by the following formula (4).

[Chemical Formula 4]

In Formula 4, R ₁ to R ₆ are each independently hydrogen, halogen, a C1 to C10 alkyl group, a C1 to C10 haloalkyl group, or a combination thereof.

The aromatic hydrocarbon-based organic solvent is selected from the group consisting of benzene, fluorobenzene, 1,2-difluorobenzene, 1,3-difluorobenzene, 1,4-difluorobenzene, 1,2,3- , 1,2,4-trifluorobenzene, chlorobenzene, 1,2-dichlorobenzene, 1,3-dichlorobenzene, 1,4-dichlorobenzene, 1,2,3-trichlorobenzene, 4-trichlorobenzene, iodobenzene, 1,2-diiodobenzene, 1,3-diiodobenzene, 1,4-diiodobenzene, 1,2,3-triiodobenzene, 1,2,4 - triiodobenzene, toluene, fluorotoluene, 1,2-difluorotoluene, 1,3-difluorotoluene, 1,4-difluorotoluene, 1,2,3-trifluorotoluene, 1,2,4-trifluorotoluene, chlorotoluene, 1,2-dichlorotoluene, 1,3-dichlorotoluene, 1,4-dichlorotoluene, 1,2,3-trichlorotoluene, 1,2,4 - trichlorotoluene, iodotoluene, 1,2-diiodotoluene, 1,3-diiodotoluene, 1,4-diiodotol Ene, 1,2,3-tree-iodo toluene, 1,2,4-iodo toluene, xylene, or may be a combination thereof.

The non-aqueous electrolyte may further include vinylene carbonate or an ethylene carbonate-based compound represented by the following formula (5) to improve battery life.

[Chemical Formula 5]

Wherein R ₇ and R ₈ are each independently a hydrogen, a halogen group, a cyano group (CN), a nitro group (NO ₂ ) or a C1 to C5 fluoroalkyl group, and at least one of R ₇ and R ₈ Is a halogen group, a cyano group (CN), a nitro group (NO ₂ ) or a C1 to C5 fluoroalkyl group.

Representative examples of the ethylene carbonate-based compound include, for example, difluoroethylene carbonate, chloroethylene carbonate, dichloroethylene carbonate, bromoethylene carbonate, dibromoethylene carbonate, nitroethylene carbonate, cyanoethylene carbonate, fluoroethylene carbonate, . When the vinylene carbonate or the ethylene carbonate compound is further used, the amount of the vinylene carbonate or the ethylene carbonate compound can be appropriately controlled to improve the life.

The sodium salt is dissolved in the non-aqueous organic solvent to act as a source of sodium ions in the cell to enable operation of the basic secondary cell and to promote the movement of sodium ions between the anode and the cathode .

More specifically, the sodium salt is _{NaClO 4, NaPF 4, NaPF 6} , NaAsF 6, may be NaTFSI, Na Beti (NaN [SO 2 C 2 F 5] 2) or a combination thereof.

The concentration of the sodium salt may be from 0.001 to 10M, and more specifically, from 0.1 to 2.0M. When the concentration of the sodium salt is within the above range, the electrolyte has an appropriate conductivity and viscosity, so that it can exhibit excellent electrolyte performance and the sodium ion can effectively move.

The negative electrode active material layer positioned on the surface of the negative electrode collector may include a negative electrode active material, a conductive material, and / or a binder, and the negative electrode active material may include a carbon-based material and / or a sodium intercalation material.

The carbon-based material may be natural graphite, artificial graphite, soft carbon, hard carbon, or a combination thereof. More specifically, it may be hard carbon.

The sodium intercalation material may be selected from the group consisting of Li ₄ Ti ₅ O ₁₂ , NaCo ₂ O ₄ , Na ₂ Ti ₃ O ₇ , Fe ₃ O ₄ , TiO ₂ , Sb ₂ O ₄ , Sb / C composite, SnSb / C A composite, an amorphous P / C composite, or a combination thereof. More specifically, it may be Li ₄ Ti ₅ O ₁₂ .

The negative electrode active material layer also includes a binder, and may optionally further include a conductive material.

The binder serves to adhere the anode active material particles to each other and to adhere the anode active material to the current collector. Typical examples thereof include polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, polyvinyl chloride, Such as polyvinyl chloride, polyvinyl fluoride, polymers comprising ethylene oxide, polyvinyl pyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, styrene-butadiene rubber, Styrene-butadiene rubber, epoxy resin, nylon, and the like may be used, but the present invention is not limited thereto.

The conductive material is used for imparting conductivity to the electrode. Any material can be used as long as it does not cause any chemical change in the battery. Examples of the conductive material include natural graphite, artificial graphite, carbon black, acetylene black, , Carbon-based materials such as carbon fibers; Metal powders such as copper, nickel, aluminum, and silver, or metal-based materials such as metal fibers; Conductive polymers such as polyphenylene derivatives; Or a mixture thereof may be used.

The current collector may be a copper foil, a nickel foil, a stainless steel foil, a titanium foil, a nickel foil, a copper foil, a polymer substrate coated with a conductive metal, or a combination thereof.

The negative electrode is prepared by mixing an active material, a binder, and a conductive material in a solvent to prepare an active material composition, and applying the composition to a current collector. The method of manufacturing the electrode is well known in the art, and therefore, a detailed description thereof will be omitted herein. As the solvent, N-methylpyrrolidone or the like can be used, but it is not limited thereto.

In the solid electrolyte, the solid electrolyte is a substance which can move with a high speed of sodium ions and can be stable with an aqueous solution and an organic solution. The solid electrolyte is composed of an amorphous ion conductive material (oxide-based glass, oxide / sulfide based glass) A sodium superionic conductor (NASICON), a sodium sulfide based solid electrolyte, a sodium oxide based solid electrolyte, or a combination thereof.

More specifically, it may be nacillic, and in this case, the ionic conductivity can be further improved.

The cathode current collector included in the anode portion may be carbon paper, carbon fiber, carbon cloth, carbon felt, metal thin film, or a combination thereof, and more specifically carbon paper. In the case of carbon paper, by-products that may arise from oxidation / reduction reactions of other metal ions contained in the sodium-containing solution can be minimized.

The porosity of the positive electrode collector may be in the range of 1 탆 to 250 탆. When these ranges are satisfied, it is possible to constitute an electrode having a large surface area to induce more electrode reactions.

Hereinafter, examples and comparative examples of the present invention will be described. The following embodiments are only examples of the present invention, and the present invention is not limited to the following embodiments.

Example: Preparation of secondary battery

Manufacture of anode part

Carbon paper (Fuel Cell Store, 2050-A) was used as a current collector. After the seawater in the anode compartment was charged, the collector was impregnated with seawater to prepare a cathode compartment.

The porosity of the carbon paper is 28 mu m.

Manufacture of cathode part

Stainless steel (McMASTER) was used as a collector. A hard carbon (MTI): super P carbon black (TIMCAL): poly (terafluoroethylene) as a binder was mixed on the current collector at a ratio of 70:20:10 (wt%) to form a negative electrode active material layer, .

After the organic electrolyte in the negative electrode container was charged, the prepared negative electrode was impregnated.

The organic electrolyte was ethylene carbonate (EC): was prepared by mixing: (volume ratio 1: 1) and 1M NaClO ₄ of the sodium salt (Aldrich), diethylene carbonate (DEC).

Preparation of Solid Electrolyte

NASICON (Na ₃ Zr ₂ Si ₂ PO ₁₂ ) was used as a solid electrolyte. The solid electrolyte was prepared by a solid-state reaction in this laboratory. The solid phase reaction well known in the art will omit specific methods.

And a solid electrolyte was positioned between the anode portion and the cathode portion. The thickness of the solid electrolyte is 1 mm.

Manufacture of hydrogen discharge

A gas pipe is connected to the upper end of the vessel constituting the anode part so that hydrogen can be discharged, and an opening / closing valve is provided at one side of the gas pipe so that hydrogen generated in the anode part can be discharged if necessary. The sodium-containing solution was supplied into the anode part, and when the discharge was completed or the discharge was completed after the discharge was started, the opening / closing valve provided in the gas pipe was opened to draw hydrogen out of the anode part.

Experimental Example: Evaluation of Battery Characteristics

Evaluation of charge / discharge characteristics

2 is charge / discharge data of a secondary battery according to an embodiment of the present invention.

From Fig. 2, it can be seen that the sodium ions dissolved in the seawater are accumulated in the hard carbon in the cathode by charging the seawater battery. The accumulated sodium ions are discharged to the seawater again while producing electricity when the battery is discharged. The charging voltage is about 3 V and the discharge voltage is about 2.3V. About 31% irreversible capacity appeared in the first cycle, indicating the amount consumed in the formation of the solid electrolyte interface (SEI) on the cathode surface when sodium ions first enter the cathode for the first time. After SEI formation, stable reversible capacity is shown.

Evaluation of cycle characteristics

3 is cycle characteristic data of a secondary battery according to an embodiment of the present invention.

3 shows stable reversible capacity after SEI formation in the first cycle and 84% efficiency after about 40 cycles.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims. As will be understood by those skilled in the art. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

Claims (16)

A liquid-phase anode portion including a sodium-containing solution and a cathode current collector impregnated in the sodium-containing solution;
A negative electrode part including a liquid organic electrolyte, a negative electrode current collector impregnated in the liquid organic electrolyte, and a negative electrode active material layer positioned on the surface of the negative electrode current collector;
A solid electrolyte positioned between the anode and the cathode; And
And a hydrogen discharge unit connected to the anode unit to discharge hydrogen generated in the anode unit to the outside during discharge.
The method according to claim 1,
Wherein the hydrogen discharge unit is installed at an upper end of an anode portion containing a sodium-containing solution to selectively open and close the battery when the battery discharges or after completion of discharge to discharge hydrogen.
3. The method according to claim 1 or 2,
Wherein an inlet portion of the sodium-containing solution and an outlet portion of the sodium-containing solution are located on one side of the anode portion.
3. The method according to claim 1 or 2,
Wherein the organic electrolyte in the cathode section comprises a non-aqueous organic solvent and / or a sodium salt.
5. The method of claim 4,
The non-aqueous organic solvent may be a carbonate-based, ester-based, ether-based, ketone-based, alcohol-based, aprotic solvent,
The sodium salt is _{NaClO 4, NaPF 4, NaPF 6} , NaAsF 6, NaTFSI, Na Beti (NaN [SO 2 C 2 F 5] 2), or production of hydrogen secondary cell of the combination of the two.
3. The method according to claim 1 or 2,
Wherein the negative electrode active material layer located on the surface of the negative electrode collector comprises a negative electrode active material, a conductive material and / or a binder, and the negative electrode active material comprises a carbon-based material and / or a sodium intercalation material. battery.
The method according to claim 6,
Wherein the carbon-based material is natural graphite, artificial graphite, soft carbon, hard carbon, or a combination thereof.
The method according to claim 6,
The sodium intercalation material may be selected from the group consisting of Li ₄ Ti ₅ O ₁₂ , NaCo ₂ O ₄ , Na ₂ Ti ₃ O ₇ , Fe ₃ O ₄ , TiO ₂ , Sb ₂ O ₄ , Sb / C composite, SnSb / C A composite, an amorphous P / C composite, or a combination thereof.
The method according to claim 6,
The conductive material may be a carbon-based material that is natural graphite, artificial graphite, carbon black, acetylene black, ketjen black, or carbon fiber; Copper, nickel, aluminum, or silver metal powder; Metal fiber; Conductive polymers; Or a mixture thereof.
The method according to claim 6,
The binder may be selected from the group consisting of polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, polymers comprising ethylene oxide, polyvinyl pyrrolidone, polyurethane, poly Wherein the secondary battery is a hydrogen-producing secondary battery, wherein the secondary battery is tetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, styrene-butadiene rubber, acrylated styrene-butadiene rubber, epoxy resin, nylon or a combination thereof.
3. The method according to claim 1 or 2,
The solid electrolyte may be an amorphous ion conductive material such as a phosphorus-based glass, an oxide / sulfide based glass, a Na superionic conductor (NASICON), a sodium sulfide based solid electrolyte, a sodium oxide based solid electrolyte, Hydrogen, and combinations thereof.
3. The method according to claim 1 or 2,
Wherein the positive electrode current collector is carbon paper, carbon fiber, carbon cloth, carbon felt, metal thin film, or a combination thereof.
3. The method according to claim 1 or 2,
Wherein the cathode current collector has a porosity of 1 m to 250 m.
3. The method according to claim 1 or 2,
Wherein the secondary battery has the following reaction formula (1) and / or (2) at the anode part when discharged.
[Reaction Scheme 1]
Na ⁺ + H ₂ O + e ^- -> NaOH + 1 / 2H ₂
[Reaction Scheme 2]
Na ⁺ + 1 / 2H ₂ O + 1 / 4O ₂ + e ^- -> NaOH
3. The method according to claim 1 or 2,
Wherein the secondary battery has the following reaction formula (3) and / or (4) at the time of charging.
[Reaction Scheme 3]
NaCl -> Na + 1 / 2Cl ₂
[Reaction Scheme 4]
NaOH -> Na + 1 / 2H ₂ O + 1 / 4O ₂
3. The method according to claim 1 or 2,
Wherein the sodium-containing solution is seawater.

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