WO2013125853A1 - Sodium secondary battery and method for manufacturing sodium secondary battery - Google Patents

Description

Sodium secondary battery and manufacturing method of sodium secondary battery

The present invention relates to a sodium secondary battery and a method for manufacturing the same, and easy to process, to a method for manufacturing a sodium secondary battery that is easy to control the thickness of the electrode and the content of the active material.

Generally, a battery may be classified into a disposable primary battery and a rechargeable battery that can be charged many times. Among them, the secondary battery has been popularized as an essential energy source of portable electronic devices such as laptops, camcorders, and mobile phones in that it can be used many times.

In recent years, secondary batteries have been changed in size and size depending on their purpose, ranging from large-capacity batteries for power storage, medium-size batteries applied to transportation vehicles, and small batteries used as power sources for portable devices. It is becoming a trend.

This secondary battery is composed of a negative electrode, a positive electrode, an electrolyte and a current collector. In the positive electrode, a reduction reaction caused by electrons generated at the negative electrode occurs, and the current collector supplies electrons generated from the negative electrode to the positive electrode active material when the battery is discharged, or electrons supplied from the positive electrode to the negative electrode active material at the time of charging. do.

Among these secondary batteries, sodium secondary batteries use molten metal sodium (Na) as the cathode, sulfur (S) as the anode, and the cathode and the cathode are selective for sodium ions, as in Korean Patent Publication No. 19960002926. It is configured to be segregated into a solid electrolyte tube made of alumina or ceramic having permeability, so that sodium ions can pass through the solid electrolyte tube.

Sodium secondary battery has excellent competitiveness in terms of supply and demand for materials and manufacturing cost by using rich sodium on the earth, and has the advantage of making a large capacity battery into a simple structure compared to lithium ion batteries.

Accordingly, the sodium secondary battery has a similar energy density as that of the conventional secondary battery, and is inexpensive, and can be manufactured with a long power conservation time. Therefore, when used as a secondary battery for renewable energy storage such as solar or wind power, a large capacity of electric power can be used. It is emerging as a next-generation storage medium that can be stored efficiently.

However, when molten sulfur is used as the cathode, a high temperature operating temperature of about 350 ° C. or more is required, and thus research on an anode that can replace sulfur is continued. Applicant has found that nickel hydroxide is very suitable as a positive electrode that can prevent the reduction of battery capacity compared to sulfur and can be operated at relatively low operating temperature below 200 ° C. Based on this finding, reaction of positive electrode immersed in electrolyte While maximizing the area, it has come to propose a method for producing a positive electrode easy to manufacture process, easy to control the content of the active material.

SUMMARY OF THE INVENTION An object of the present invention is to provide a sodium secondary battery that prevents peeling or desorption of a positive electrode active material layer from a current collector, free of battery design according to capacity, and can be miniaturized and easy to manufacture. An object of the present invention is to provide a method of manufacturing a sodium secondary battery that can easily control the thickness of a cathode active material, a method of manufacturing a small size cathode of a large-capacity battery, and can easily control the thickness of an electrode and the content of an active material.

A method of manufacturing a sodium secondary battery according to the present invention includes the steps of: a) inserting a current collector into a cathode space partitioned from a cathode space by a sodium ion conductive solid electrolyte; And b) injecting an active material containing a positive electrode active material into the positive electrode space into which the current collector is inserted.

In the method of manufacturing a sodium secondary battery according to an embodiment of the present invention, step b) comprises the steps of b1) injecting a particulate phase containing a cathode active material and conductive particles into the cathode space; And injecting a binder solution containing a viscosity modifier and a binder into the anode space and drying the same.

In the method of manufacturing a sodium secondary battery according to an embodiment of the present invention, b) step b3) a slurry containing a positive electrode active material, a conductive particle, a viscosity regulator and a binder in the positive electrode space and drying; Can be.

In the method of manufacturing a sodium secondary battery according to an embodiment of the present invention, step a) is a cylindrical metal housing, one end of which is sealed in one end and the other end is open, located inside the metal housing, Providing a sodium ion conductive solid electrolyte tube, a safety tube, and a wicking tube on which molten sodium is loaded, the anode space having a concentric structure sequentially positioned from the outer side to the inner side, wherein the anode space is disposed between the solid electrolyte tube and the metal housing. It may be a space of.

In the method of manufacturing a sodium secondary battery according to an embodiment of the present invention, the current collector may be wound to have a concentric structure with the metal housing.

In the method of manufacturing a sodium secondary battery according to an embodiment of the present invention, the current collector may be in the form of a foam (foam), film (film), mesh (mesh), felt (felt) or porous foil (perforated film) shape .

In the method of manufacturing a sodium secondary battery according to an embodiment of the present invention, the current collector may be one or more selected from carbon, nickel, titanium, yttrium, calcium, chromium, cobalt, zinc, graphite and graphene.

In the method of manufacturing a sodium secondary battery according to an embodiment of the present invention, the conductive particles may include carbon, nickel, titanium, yttrium, calcium, chromium, cobalt, zinc, graphite, graphene or a mixture thereof.

In the method of manufacturing a sodium secondary battery according to an embodiment of the present invention, the particulate form may contain 0.5 to 20 parts by weight of conductive particles based on 100 parts by weight of the positive electrode active material.

In the method of manufacturing a sodium secondary battery according to an embodiment of the present invention, the cathode active material may include nickel hydroxide (Ni (OH) ₂ ).

In the method of manufacturing a sodium secondary battery according to an embodiment of the present invention, the binder solution may have a viscosity of 0.01 P to 10,000 P.

In the method of manufacturing a sodium secondary battery according to an embodiment of the present invention, the viscosity of the slurry may be 0.01 P to 10,000 P.

In the manufacturing method of the sodium secondary battery according to an embodiment of the present invention, the viscosity modifier is carboxymethyl cellulose (CMC; carboxymethyl cellulose), methyl cellulose (methylcellulose), ethyl cellulose (ethyl cellulose) and hydroxypropyl methyl cellulose (HPMC) at least one selected from hydroxypropyl methylcellulose, and the binder may be polytetrafluoroethylene (PTFE; polytetrafluoroethylene), polyvinyl alcohol (PVA), polyolefine, polyethylene oxide (PEO), or polyethylen oxide (PEO). Mixtures thereof.

In the method of manufacturing a sodium secondary battery according to an embodiment of the present invention, the binder solution may contain a binder of 0.1 to 20% by weight.

In the method for manufacturing a sodium secondary battery according to an embodiment of the present invention, the slurry is based on 100 parts by weight of the positive electrode active material, 0.1 to 20 parts by weight of conductive particles, 0.1 to 10 parts by weight of the viscosity regulator and 0.1 to 20 parts by weight of the binder It may contain.

In the sodium secondary battery according to an embodiment of the present invention, after step b), c) injecting an electrolyte into the anode space; may be further performed.

Sodium secondary battery according to the present invention comprises a sodium ion conductive solid electrolyte partitioning the negative electrode space and the positive electrode space; A sodium-containing cathode located in the cathode space; And a current collector positioned in the positive electrode space and a particulate form filling the positive electrode space in which the current collector is located, wherein the particulate includes a positive electrode containing a positive electrode active material.

In the sodium secondary battery according to an embodiment of the present invention, the particulate form filling the positive electrode space may be bound by drying of a binder injected into the positive electrode space in a solution form.

In the sodium secondary battery according to an embodiment of the present invention, the particulate may further include conductive particles.

In the sodium secondary battery according to an embodiment of the present invention, the particulate form may contain 0.5 to 20 parts by weight of conductive particles based on 100 parts by weight of the positive electrode active material.

In the sodium secondary battery according to an embodiment of the present invention, the cathode active material may include nickel hydroxide (Ni (OH) ₂ ).

In the sodium secondary battery according to an embodiment of the present invention, the negative electrode may be molten sodium.

In the sodium secondary battery according to an embodiment of the present invention, the particulate may fill the positive electrode space to a height corresponding to the level of molten sodium in the negative electrode space.

In the sodium secondary battery according to an embodiment of the present invention, the sodium secondary battery is located in the cylindrical metal housing, the metal housing, the sodium ion conductive solid electrolyte is located with a concentric structure sequentially from the outside of the metal housing to the inside A tube, a safety tube, and a wicking tube carrying molten sodium are included, and the anode space may be a space between the solid electrolyte tube and the metal housing.

In the sodium secondary battery according to an embodiment of the present invention, the empty space of the anode space filled with particulates may be filled with an electrolyte solution.

In the manufacturing method according to the present invention, after the current collector is not provided with a positive electrode active material into the positive electrode space, the particulate and the binder solution is added sequentially or integrated into a slurry to produce a positive electrode in the positive electrode space itself, as a slurry Compared to the conventional process of manufacturing, coating, drying, rolling, winding, and inserting into the anode space, the process is simplified, the required investment costs are reduced, and the process input manpower is also reduced. It is higher, free from peeling or desorption of the positive electrode active material layer generated during the rolling of the electrode in the existing process, easy mechanical processing, free design of the battery according to the capacity, easy to control the thickness of the positive electrode active material, There is an advantage that a large capacity battery can be manufactured in a small size, there is an advantage having a high mass production.

The sodium secondary battery according to the present invention not only frees the design of the battery, but also prevents peeling or detaching of the current collector and the positive electrode active material layer, and has an advantage of controlling the capacity of the battery by simply changing the size of the positive electrode space.

1 is a cross-sectional view showing an example of a battery structure in a manufacturing method according to an embodiment of the present invention,

2 is a cross-sectional view showing an example of a manufacturing method according to an embodiment of the present invention,

3 is a process chart showing an example of a manufacturing method according to an embodiment of the present invention,

4 is a process chart showing another example of a manufacturing method according to an embodiment of the present invention,

5 is a cross-sectional view of a secondary battery according to an exemplary embodiment of the present invention.

Hereinafter, a sodium secondary battery of the present invention and a method of manufacturing the same will be described in detail with reference to the accompanying drawings. The drawings introduced below are provided by way of example so that the spirit of the invention to those skilled in the art can fully convey. Accordingly, the present invention is not limited to the drawings presented below and may be embodied in other forms, and the drawings presented below may be exaggerated to clarify the spirit of the present invention. Also, like reference numerals denote like elements throughout the specification.

At this time, if there is no other definition in the technical terms and scientific terms used, it has a meaning commonly understood by those of ordinary skill in the art to which the present invention belongs, the gist of the present invention in the following description and the accompanying drawings Descriptions of well-known functions and configurations that may be unnecessarily blurred are omitted.

A method of manufacturing a sodium secondary battery according to the present invention includes the steps of: a) inserting a current collector into a cathode space partitioned from a cathode space by a sodium ion conductive solid electrolyte; And b) injecting an active material containing a positive electrode active material into the positive electrode space into which the current collector is inserted.

In the method of manufacturing a sodium secondary battery according to an embodiment of the present invention, step b) comprises the steps of b1) injecting a particulate phase containing a cathode active material and conductive particles into the cathode space; And injecting a binder solution containing a viscosity modifier and a binder into the anode space and drying the same.

As described above, in the method for manufacturing a sodium secondary battery according to the present invention, the current collector is introduced into a positive electrode space partitioned by a sodium ion conductive solid electrolyte, separated from the positive electrode active material, and then the current collector and the positive electrode in the positive electrode space. A sodium secondary battery is manufactured by binding an active material.

That is, after the current collector is introduced into the positive electrode space, the particles and the binder including the positive electrode active material are sequentially or simultaneously introduced into the positive electrode space into which the current collector is inserted, thereby binding between particles including the positive electrode active material and between the particles and the current collector. Can be.

In the method for manufacturing a sodium secondary battery according to the present invention, after applying a slurry containing a positive electrode active material to a current collector and drying to prepare a positive electrode, the prepared positive electrode is not wound, molded and / or cut and inserted into a battery, Since the anode is manufactured directly in the anode space of the structure itself, the anode can be manufactured in a very simple process compared to the conventional process according to the order of the slurry production, application, drying, rolling, winding, and insertion into the anode space. It can reduce the investment cost and manpower required for anode production, thereby lowering the production cost, free from peeling or desorption of the cathode active material layer generated during rolling of the electrode in the existing process, and easy for mechanical processing There is this. In addition, conventionally, in order to design and change the capacity of a battery, a battery of a whole new system is designed by different kinds of positive electrode active materials, or a structure in which a plurality of positive electrodes are stacked to design a desired level of capacity while using the same positive electrode active materials. There was a limit to which a change must be made. However, in the manufacturing method of the present invention, the capacity of the battery can be changed only through an extremely simple method of changing the size of the anode space or controlling the total amount of particulates injected into the anode space. That is, the manufacturing method according to the present invention is extremely easy and free to design the battery according to the capacity, only the separation distance between the current collector and the current collector in the positive electrode space and / or the case (including a conductive case) for separating the battery from the outside By controlling the separation distance between the) and the current collector, the thickness of the positive electrode active material layer can be adjusted, it is very easy to control the thickness of the positive electrode active material layer, there is an advantage that a large-capacity battery can be manufactured in a small size.

Specifically, in the method of manufacturing a sodium secondary battery according to an embodiment of the present invention, step b) comprises the steps of b1) injecting a particulate phase containing a positive electrode active material and conductive particles into the positive electrode space; And b2) injecting and drying a binder solution containing a viscosity modifier and a binder into the anode space.

Specifically, in the method of manufacturing a sodium secondary battery according to an embodiment of the present invention, step b) is a step of b3) adding a slurry containing a positive electrode active material, a conductive particle, a viscosity control agent and a binder in the positive electrode space and drying; It may include.

Specifically, in step b), the current collector is introduced into the positive electrode space, the particle input including the positive electrode active material and the binder solution containing the binder are sequentially performed, or the current collector is injected into the positive electrode space and the positive electrode active material and the binder are sequentially added. It may comprise the step of the input of the slurry comprising a sequentially.

In one embodiment according to the present invention, the particulate phase may further contain conductive particles together with the positive electrode active material, which serves to reduce the resistance between the current collector and the positive electrode active material, that is, to reduce the internal resistance of the battery. Can play a role.

Specifically, the particulate form may contain 0.5 to 20 parts by weight of conductive particles based on 100 parts by weight of the positive electrode active material. The weight ratio of the conductive particles to the positive electrode active material is a weight ratio in which a low resistance path can be uniformly formed between the positive electrode active material and the current collector without interfering with the positive electrode reaction generated in the positive electrode active material.

As in the related art, in the case of using a positive electrode in which a positive electrode active material layer is laminated on a current collector, the thickness of the positive electrode active material layer is usually limited in order to secure stable formability (processability) of the positive electrode. Under such constraints of thickness, the amount of the positive electrode active material decreases as the conductors introduced to decrease the internal resistance of the battery decrease, so that the amount of the conductor and the positive electrode active material can only be adjusted to a level that appropriately decreases the resistance and ensures adequate capacity. . However, the manufacturing method according to an embodiment of the present invention is to prepare a positive electrode (current collector and positive electrode active material) in the positive electrode space by packing a particulate containing a positive electrode active material in the positive electrode space, so that the positive electrode active material layer from the thickness constraint Depending on the freedom, the particulate phase may contain an amount of conductive particles that are determined primarily in consideration of the reduction in battery internal resistance. That is, compared with the prior art, the particulate form can freely contain an amount of conductive particles that can effectively reduce the internal resistance of the battery.

In the manufacturing method according to an embodiment of the present invention, the average particle size (diameter) of the positive electrode active material may be 1 ㎛ to 100 ㎛, the average particle size of the conductive particles may be 0.1 ㎛ to 30 ㎛. If the average particle size of the positive electrode active material is too small, less than 1 μm, the specific surface area of the positive electrode active material becomes large, but there is a risk that the smooth input of the binding solution or the smooth input and stable contact of the electrolyte described below are impaired. There is a risk that a binder is required to degrade battery characteristics. If the average particle size of the positive electrode active material is too large to exceed 100 µm, there is a risk that the battery characteristics are deteriorated by the reduction of the specific surface area of the positive electrode active material. The conductive particles form a low resistance path between the positive electrode active material particles, the positive electrode active material and the current collector to reduce the internal resistance of the battery, and the amount of the positive electrode active material filled by the conductive particles in the same volume of the positive electrode space is reduced. To prevent and effectively form a low resistance path, when the average particle size (diameter) of the positive electrode active material is 1 μm to 100 μm, the average particle size of the conductive particles may be 0.1 μm to 30 μm.

According to an embodiment of the present invention, after step b) is performed, more specifically, after step b2) or b3) is performed, c) injecting an electrolyte into the anode space; Can be.

The electrolyte serves to conduct sodium ions quickly and uniformly, and the electrolyte salt (sodium salt) contained in the electrolyte may include hydroxide, borate, phosphate, or a mixture thereof. Specifically, the electrolyte salt may be sodium hydroxide (NaOH), trisodium phosphate (Na ₃ PO ₄ ), sodium pyrophosphate (Na ₂ HPO ₄ ), sodium metaborate (NaBO ₂ ), borax (Na ₂ B ₄ O ₇ ), Boric acid (H ₃ BO ₃ ) or mixtures thereof. In this case, the electrolyte may include an aqueous or non-aqueous electrolyte, and the electrolyte may contain 2 to 50 wt% of an electrolyte salt.

In the manufacturing method according to an embodiment of the present invention, before the step a) or after the step b), or optionally after the step c), i) injecting a negative electrode into the positive electrode space and the negative electrode space by a sodium ion conductive solid electrolyte; It may further include.

Specifically, in the manufacturing method according to an embodiment of the present invention, at least a sodium ion conductive solid electrolyte is injected into the sealed battery case, and the space inside the battery case is divided into a positive electrode space and a negative electrode space by a sodium ion conductive solid electrolyte. ; Injecting a cathode into the cathode space; Manufacturing a positive electrode in the positive electrode space through steps a) and b), optionally steps a), b) and c); And sealing the battery case.

Specifically, in the manufacturing method according to an embodiment of the present invention, at least a sodium ion conductive solid electrolyte is injected into the sealed battery case, and the space inside the battery case is divided into a positive electrode space and a negative electrode space by a sodium ion conductive solid electrolyte. ; Manufacturing a positive electrode in the positive electrode space through steps a) and b), optionally steps a), b) and c); Injecting a cathode into the cathode space; And sealing the battery case.

In the manufacturing method according to an embodiment of the present invention, the negative electrode introduced into the negative electrode space is an electrode on which the negative electrode active material layer is formed on the negative electrode current collector, or a negative electrode such as rod-shaped conductive graphite on the negative electrode active material forming a liquid phase at a battery operating temperature The current collector may be charged.

In the manufacturing method according to an embodiment of the present invention, the cathode (cathode active material) may be metal sodium.

In the manufacturing method according to an embodiment of the present invention, the positive electrode active material (particle) may be nickel hydroxide.

In the manufacturing method according to an embodiment of the present invention, after the particulate phase is added to the anode space, the binder solution is added to the anode space, or after the slurry is injected into the anode space, the anode constituent materials (particulate matter) For further homogeneous and stable packing and homogeneous distribution, the step of applying a physical vibration to the anode space may be further performed. The physical vibration can be any vibration as long as it causes a uniform and homogeneous filling of powder particles. For example, various physical vibrations, such as an impact from an ultrasonic impact between a battery case and an external object, to an ultrasonic vibration. This can be used.

In the manufacturing method according to an embodiment of the present invention, b1) a step of injecting a particulate phase containing a positive electrode active material and conductive particles into the anode space; And b2) injecting and drying a binder solution containing a viscosity modifier and a binder into the positive electrode space, and when the positive electrode is prepared, the binder solution binds the particles introduced into the particles and at the same time, the particles and the current collector. It can serve to bind.

The viscosity modifier contained in the binding solution may be a cellulose based at least one selected from carboxymethyl cellulose (CMC), methyl cellulose (methylcellulose), ethyl cellulose and hydroxypropyl methylcellulose (HPMC). .

The binding solution may have a viscosity of 0.01 P to 10,000 P at room temperature and normal pressure, which flows through the empty space between particles filled in the anode space into which the current collector is inserted, while uniformly binding between the particles and between the particles and the current collector. It is the viscosity at which the binding solution can be homogeneously distributed in the anode space by capillary force. The binder solution may contain a viscosity modifier to satisfy the above-mentioned viscosity.

The binder contained in the binding solution may include polytetrafluoroethylene (PTFE), polyvinyl alcohol (PVA), polyolefine, polyethylene oxide (PEO) or a mixture thereof. The binder contained in the binding solution serves to bind the particles and the particles and the current collector to each other with physical strength. The binder solution may contain 0.1 to 20% by weight of the binder, the content of this binder does not interfere with the positive electrode reaction, does not interfere with the conduction of sodium ions, and after drying of the binder solution, even when a physically stable positive electrode is produced The electrolyte may be added homogeneously.

The solvent of the binding solution may be a substance in which the viscosity modifier and binder described above are dissolved.

In the manufacturing method according to an embodiment of the present invention, b3) a slurry containing a positive electrode active material, a conductive particle, a viscosity control agent and a binder in the positive electrode space and drying; including, when the positive electrode is produced, particulate And similar to the case where the binder solution is added sequentially, the viscosity modifier is carboxymethyl cellulose (CMC; carboxymethyl cellulose), methyl cellulose (methylcellulose), ethyl cellulose (ethyl cellulose) and hydroxypropyl methylcellulose (HPMC) At least one selected from cellulose-based, the binder may include polytetrafluoroethylene (PTFE; polytetrafluoroethylene), polyvinyl alcohol (PVA; polyvinyl alcohol), polyolefin (polyolefine), polyethylene oxide (PEO; polyethylen oxide) or a mixture thereof The solvent of the slurry may be a substance in which a viscosity modifier and a binder are dissolved. It is okay if.

The slurry (active material slurry) is 0.1 to 0.1 parts based on 100 parts by weight of the positive electrode active material in terms of stable binding with the current collector, smooth and homogeneous packing, and easy ion transfer by the electrolyte solution injected into the positive electrode space after slurry drying. It may contain 20 parts by weight of conductive particles, 0.1 to 10 parts by weight of the viscosity regulator and 0.1 to 20 parts by weight of the binder, the viscosity regulator may be contained so that the slurry can have a viscosity of 0.01 P to 10,000 P at room temperature normal pressure.

Hereinafter, a specific example of a sodium secondary battery having a tubular structure in which a negative electrode is positioned in the center will be described in detail. However, the manufacturing method of the present invention will be described in detail, which is presented to help understanding of the present invention, and the present invention provides a structure of a sodium secondary battery. Of course, it can not be limited by. As described above, the sodium secondary battery of the present invention and a method of manufacturing the same may include all structures of the sodium secondary battery in which the sealed case and the inner space of the sealed case are partitioned into a positive electrode space and a negative electrode space by a sodium ion conductive solid electrolyte. have. The tubular structure may include a cell structure used in a conventional molten sodium sulfur battery, and may include a tubular structure in which the positive electrode is located at the center. In addition, the sodium secondary battery to be manufactured may include a plate-like structure, which is a plate-shaped sodium ion conductive solid electrolyte is placed in a sealed case having an inner space, the inner space is the positive electrode space and the negative electrode space It includes a structure that is divided into compartments.

1 is an example illustrating a method of manufacturing a sodium secondary battery according to an exemplary embodiment of the present invention. That is, FIG. 1 is a view illustrating an example of a battery structure partitioned into a positive electrode space and a negative electrode space by a sodium ion conductive solid electrolyte in a method of manufacturing a sodium secondary battery according to an embodiment of the present invention.

As shown in FIG. 1, in the battery structure, the metal housing 100 is positioned at the outermost side, the wicking tube 420 is positioned at the center thereof, and the metal housing 100 is disposed at the outer side of the metal housing 100 inside the metal housing 100. In the center direction, the solid electrolyte tube 300, the safety tube 410, and the wicking tube 420 may be sequentially provided.

That is, from the outside of the metal housing 100 to the inside, the solid electrolyte tube 300, the safety tube 410 and the wicking tube 420 has a concentric structure, to provide a battery structure provided inside the metal housing 100 Can be.

The metal housing 100 may include a cylindrical shape in which one end of both ends is sealed and the other end is open, and a cover (not shown) for sealing the open end of the metal housing 100 after the manufacture of the battery is completed. It may include. A solid electrolyte tube 300 that selectively transmits sodium ions may be positioned adjacent to the metal housing 100.

The solid electrolyte of the solid electrolyte tube 300 includes a solid electrolyte conventionally used in the battery field for the selective conduction of sodium ions. For example, a sodium super ion conductor (NaSICON), β "alumina or The wicking tube 420 positioned at the innermost, ie central portion of the metal housing 100 may have a tube shape having a through hole formed at a lower end thereof, and the safety tube 410 is a wicking tube. Located outside the 420 may have a predetermined distance and have a structure surrounding the wicking tube (420).

The negative electrode active material including molten sodium may be provided inside the wicking tube 420, and fills an empty space between the wicking tube 420 and the safety tube 410 through a through hole formed under the wicking tube 420. It can have

The dual structure of the wicking tube 420 and the safety tube 410 prevents a violent reaction between the positive electrode active material and the negative electrode active material when the solid electrolyte tube 300 breaks, and maintains a constant level of molten sodium even during discharge due to capillary force. It is a sustainable structure.

Although FIG. 1 illustrates an example of a battery structure including a cylindrical metal housing, a tubular solid electrolyte, a tubular safety tube, and a wicking tube, the present invention provides a technique for directly manufacturing a cathode in an anode space. As provided, of course, the present invention is not limited by the shape, material or size of the battery structure.

2 is a cross-sectional view of a method for manufacturing a sodium secondary battery according to an embodiment of the present invention. After the battery structure shown in FIG. 1 is provided, a space between the metal housing 100 and the solid electrolyte tube 300 is provided. An example of the step of forming an anode in the phosphorous anode space 1 is shown in detail.

As in the example of FIG. 2, the slurry containing the positive electrode active material is not wound and inserted into the current collector in the positive electrode space 1 of the provided battery structure, and the positive electrode active material is not attached (or fixed). The current collector itself (active material unformed current collector) can be placed.

The current collector may be in the form of a foam, film, mesh, felt or porous foil, and the current collector may be carbon, nickel, titanium, yttrium, calcium, chromium, One or more may be selected from cobalt, zinc, graphite and graphene.

The current collector may be introduced into the anode space 1 in a rolled state in order to effectively collect electric charges while widening the reaction area of the electrode, and the current collector may be wound and input to have a concentric structure with the metal housing 100. Although it may be, of course, the present invention may not be limited by the shape of the current collector.

The manufacturing method according to an embodiment of the present invention, which winds up a current collector that is not provided with an active material and then inserts it into the positive electrode space, may prevent desorption between the active material and the current collector generated during winding, and a large amount of positive electrode active material on the current collector This has the advantage of being suitable for the manufacture of large capacity sodium batteries to be provided.

Specifically, in the case of using a single layer current collector for manufacturing a large capacity sodium battery having a capacity of 500 Ah or more, it is necessary to coat the cathode active material to a thickness of 250 mm or more. In this case, the shape of the electrode itself becomes thick and dried. Difficulties arise in machining the electrodes. That is, when the current collector with a thick positive electrode active material layer is processed into a dried shape, peeling or desorption of the positive electrode active material layer occurs, the mechanical strength is lowered, a lot of energy is consumed during processing, and the electrode is dried. There is a problem that the stability is not maintained.

As a method of eliminating this, there is a method in which a thin positive electrode active material layer is formed on a current collector, and then the number of times of winding is increased to inject the same amount of the positive electrode active material into a battery. After manufacturing the electrode coated with the active material, a process that needs to be placed in the anode space in several layers is required, and not only the manufacturing cost increases but also the size of the battery increases due to the increase in the volume of the dried cathode. have.

In the manufacturing method according to an embodiment of the present invention, after processing a current collector that is not provided with a positive electrode active material in a dried shape, the positive electrode active material generated during rolling of the electrode as the wound current collector is put into the positive electrode space Free from peeling or desorption of the layer, the material, thickness and shape of the current collector can be determined in consideration of the mechanical ductility, mechanical strength, and electrical properties of the current collector, thereby making it easier to manufacture the battery, and only the anode space. The thickness of the positive electrode active material can be controlled by adjusting the size and / or the winding interval of the current collector, and the mass production process is simplified, thereby reducing the investment cost and the production cost.

At this time, when winding the current collector, the number of windings and the winding interval (D of FIG. 2) of the current collector may be designed in consideration of the capacity of the battery, and the size of the positive electrode space 1 also takes into account the capacity of the battery. Of course, it can be designed.

FIG. 3 is an example of a process diagram in which the above-described battery structure is provided, and a metal current collector is introduced into the positive electrode space 1, and then the step of introducing a particulate phase containing the positive electrode active material is shown in detail.

In the manufacturing method according to an embodiment of the present invention, as shown in the example shown in FIG. 3, after the current collector 200 is inserted into the positive electrode space 1, the positive electrode space 1 into which the current collector 200 is introduced ) Into the particulate phase containing the positive electrode active material and the conductive particles, and then a step of adding a binder solution containing a viscosity modifier and a binder into the positive electrode space (1) in which the particulate phase is added and dried.

The positive electrode active material contained on the particles may include nickel hydroxide (Ni (OH) ₂ ), and the conductive particles, which are conductive particles, may be used as long as the conductive particles are commonly used for the positive electrode of a secondary battery, particularly a nickel hydrogen battery. For example, the conductive particles may contain carbon, nickel, titanium, yttrium, calcium, chromium, cobalt, zinc, graphite, graphene, or mixtures thereof.

As described above, in the manufacturing method according to an embodiment of the present invention, the particulate phase contains a mixed powder of the positive electrode active material particles and the conductive particles, the conductive particles are anodic reaction (Ni (OH) ₂ ↔ NiOOH) is generated It reduces the resistance between the positive electrode active material (nickel hydroxide) and the current collector.

In the manufacturing method according to an embodiment of the present invention, the particulate matter is injected into the positive electrode space 1 into which the wound current collector 200 is inserted, and between the wound current collector, the current collector 200 and the metal housing 100. The space between the) and between the solid electrolyte 300 and the metal housing 100 may be filled with particulates.

At this time, as described above, only by controlling the winding interval (D of FIG. 2) of the current collector, the thickness of the active material coated on the current collector can be controlled. The winding interval of the current collector may be changed in consideration of the capacity of the battery. For example, the winding interval of the current collector is 0.01 to 5 mm.

In the manufacturing method according to an embodiment of the present invention, as the particulate is introduced into the anode space 1 in a dry powder state, it is formed in the empty space between the cathode active material particles and the conductive particles contained in the powder, between the particles Empty spaces may be filled with the binding solution.

Thus, the volume at which the binding solution is filled can be controlled by the average particle size of the particulates. The average particle size (diameter) of the positive electrode active material contained on the particles may be 1 μm to 100 μm, and the average particle size of the conductive particles may be 0.1 μm to 30 μm.

The size of the positive electrode active material particles and the conductive particles described above is uniformly mixed between the positive electrode active material and the conductive particles, and when the particle is stably attached to the current collector 200 by the binding solution when the anode active material 1 is injected into the anode space 1. It is a preferred size for forming an active material layer having stable physical strength.

In the manufacturing method according to an embodiment of the present invention, the current collector 200 is inserted into the positive electrode space 1 of the provided battery structure, filled with particulates, and then a binder solution containing a viscosity modifier and a binder is added thereto. After drying, the positive electrode may be manufactured.

The binder solution physically and stably fixes the injected particulate phase to a current collector, and serves to uniformly fill the particulate space in the anode space 1.

The viscosity of the binder solution may be 0.01 P to 10,000 P, and the viscosity modifier contained in the binder solution is carboxymethyl cellulose (CMC), methyl cellulose, ethyl cellulose and hydroxypropyl methyl cellulose. (HPMC; hydroxypropyl methylcellulose) may be a cellulose-based selected one or more, the binder is polytetrafluoroethylene (PTFE; polytetrafluoroethylene), polyvinyl alcohol (PVA; polyvinyl alcohol), polyolefin (polyolefine), polyethylene oxide (PEO; polyethylen oxide) Or mixtures thereof. At this time, the binder solution may contain 0.1 to 20% by weight of the binder.

The solvent of the binder solution may be any substance in which the viscosity modifier and the binder are dissolved, but water, alcohol, glycerin, or a mixed solvent thereof may be used in view of easy drying at low temperatures.

The binder solution may have a viscosity of 0.01 P to 10,000 P at room temperature and normal pressure, which flows through the empty space between the particulate powder particles filled in the anode space into which the current collector 200 is inserted, and flows between the particles and between the particles and the current collector. It is a viscosity at which the binding solution can be uniformly distributed in the anode space by capillary force while binding uniformly.

The viscosity of the binder solution may be adjusted by the content of the above-described viscosity regulator, for example, the binder solution may contain a viscosity modifier so that the viscosity of the solution is 0.01 P to 10,000 P.

The binder contained in the binding solution may serve to bind the particles and the particles and the current collector to each other with physical strength. The binder solution may contain 0.1 to 20% by weight of the binder, which does not interfere with the anodic reaction by the binder during charging or discharging, does not interfere with the conduction of sodium ions entering through the solid electrolyte tube, and physically Even when a stable positive electrode is prepared, the electrolyte may be added homogeneously after drying of the binding solution.

In the manufacturing method according to an embodiment of the present invention, the battery structure for a more uniform packing of the particulate form within a short time before the step of injecting the particulate into the anode space and / or after the addition of the binder solution is dried The step of applying a physical vibration to the can be further performed. In this case, the vibration of the battery structure may include a vibration process including an ultrasonic vibration applied to the side or bottom surface of the metal housing 100.

In the manufacturing method according to an embodiment of the present invention, the particulate may be injected to fill at least a portion of the anode space (1), for example, an empty space between the wicking tube 420 and the safety tube (410) Particulates can be filled to a level corresponding to the level (height) of molten sodium filling. The binding solution may also be added to fill at least a portion of the anode space 1, and, for example, the binding solution may be filled at a level where all particulates may be impregnated.

In the manufacturing method according to an embodiment of the present invention, as shown in the example shown in Figure 4, after inserting the current collector 200 in the positive electrode space 1, the positive electrode in the positive electrode space (1) in which the current collector is injected Injecting and drying an active material slurry containing an active material, conductive particles, a viscosity modifier, and a binder may be performed.

Similar to the case where the particulate and the binder solution are sequentially added, the positive electrode active material contained in the particulate may include nickel hydroxide (Ni (OH) ₂ ), and the conductive particles, which are conductive particles, may be used in secondary batteries, particularly nickel hydrogen batteries. Any conductive particles commonly used for the positive electrode can be used. For example, the conductive particles may contain carbon, nickel, titanium, yttrium, calcium, chromium, cobalt, zinc, graphite, graphene, or mixtures thereof.

Similar to the case of sequential addition of particulate and binding solutions, the viscosity modifiers are carboxymethyl cellulose (CMC), methyl cellulose (methylcellulose), ethyl cellulose and hydroxypropyl methylcellulose (HPMC). And at least one selected from the group consisting of cellulose, and the binder may be polytetrafluoroethylene (PTFE), polyvinyl alcohol (PVA), polyolefine, polyethylene oxide (PEO) or mixtures thereof. The slurry may be a solvent in which the viscosity modifier and the binder are dissolved, but water, alcohol, glycerin, or a mixed solvent thereof may be used in view of easy drying at low temperatures.

The active material slurry is 0.1 to 20 parts by weight based on 100 parts by weight of the positive electrode active material in terms of stable binding with the current collector, smooth and homogeneous packing, and easy ion transfer by the electrolyte solution that is added to the positive electrode space after slurry drying. It may contain conductive particles, 0.1 to 10 parts by weight of the viscosity regulator and 0.1 to 20 parts by weight of the binder, the average particle size (diameter) of the positive electrode active material may be 1㎛ to 100㎛, the average particle size of the conductive particles is 0.1 May be in the range from about 30 μm.

After the addition of the active material slurry and before the drying of the injected slurry, a step of applying physical vibration to the battery structure may be further performed, and the physical vibration may include ultrasonic vibration.

In the manufacturing method according to an embodiment of the present invention, the active material slurry may be added to fill at least a portion of the positive electrode space (1), for example, the wicking tube 420 and the safety tube 410 The slurry may be filled at a level corresponding to the level (height) of molten sodium filling the void space therebetween.

In the manufacturing method according to an embodiment of the present invention, the current collector is inserted into the positive electrode space, and the particulate and the binder solution are sequentially added or the active material slurry is added, followed by drying to remove the solvent of the binder solution or slurry. Step is performed.

In drying, the active material slurry may be applied to a current collector and then dried to use drying conditions performed in a conventional manufacturing method of manufacturing an electrode for a secondary battery. For example, drying may be performed at a temperature of 50 to 150 ° C. .

After the drying step is performed, the step of introducing the electrolyte into the anode space may be further performed.

The electrolyte serves to conduct sodium ions quickly and uniformly, and the electrolyte salt (sodium salt) contained in the electrolyte may include hydroxide, borate, phosphate, or a mixture thereof. Specifically, the electrolyte salt may be sodium hydroxide (NaOH), trisodium phosphate (Na ₃ PO ₄ ), sodium pyrophosphate (Na ₂ HPO ₄ ), sodium metaborate (NaBO ₂ ), borax (Na ₂ B ₄ O ₇ ), Boric acid (H ₃ BO ₃ ) or mixtures thereof. The electrolyte solution includes an aqueous electrolyte solution, and the electrolyte solution may contain 2 to 50 wt% of an electrolyte salt.

After the providing of the battery structure before inserting the current collector or after the drying step is carried out the step of introducing the metal sodium into the wicking tube, after the addition of the electrolyte and sodium, sealing the upper part of the metal housing, Forming an electrode terminal on the outer wall of the metal housing, which may make an electrical closed loop with the external rod, may be further performed.

At this time, the introduction of sodium, the sealing of the metal housing and the formation of the electrode terminal may be used in the method and structure used in the conventional method for manufacturing a sodium sulfur battery having a structure similar to Figure 1, the description thereof is omitted. do.

The present invention provides a sodium secondary battery.

The sodium secondary battery according to the present invention includes a sodium ion conductive solid electrolyte, a negative electrode and a positive electrode.

The sodium ion conductive solid electrolyte partitions the cathode space and the anode space. In detail, the sodium ion conductive solid electrolyte may be disposed in an inner space of a battery case (including a conductive case) that separates the battery internal components from the outside, and may partition the inner space of the battery case into a cathode space and an anode space.

The current collector may be located in the positive electrode space, and the positive electrode space in which the current collector is located may be filled with particulates containing a positive electrode active material. That is, the particulate form may fill the entire anode space or a predetermined region where the current collector is located at a predetermined height.

That is, the sodium secondary battery according to the present invention comprises a sodium ion conductive solid electrolyte partitioning the cathode space and the anode space; A cathode space in which the cathode is located; And a positive electrode space in which a current collector is charged and filled with particles (packed) including a positive electrode active material. The sodium secondary battery may be manufactured by the above-described manufacturing method.

In the sodium secondary battery according to the present invention, the active material layer containing the positive electrode active material is not laminated in the current collector, but the particulate phase containing the positive electrode active material fills the positive electrode space, and the current collector is charged on the particles filling the positive electrode space. According to the shape, it is free from peeling or desorption of the positive electrode active material layer generated during rolling of the electrode (anode), and it is possible to control the thickness of the positive electrode active material by only adjusting the size of the positive electrode space and / or the winding interval of the current collector. The capacity design of the battery is extremely easy and free, and the mass production process is simplified, which can reduce the investment cost and production cost.

In the sodium secondary battery according to an embodiment of the present invention, the current collector may be in the form of a foam (film), film (film), mesh (mesh), felt (felt) or porous foil (perforated film), The whole may be one or more selected from carbon, nickel, titanium, yttrium, calcium, chromium, cobalt, zinc, graphite and graphene.

In the sodium secondary battery according to an embodiment of the present invention, the current collector located in the positive electrode space may be a wound shape or a structure in which a plurality of current collectors are spaced apart from each other. In detail based on the conventional manufacturing method, when the current collector has a wound shape, the thickness of the active material coated on the current collector may be controlled by the winding interval of the current collector. As a specific example, the winding interval of the current collector may be 0.01 to 5mm. When the current collectors are arranged to be spaced apart from each other, the arranged current collectors may be in an electrically energized state in which the top, bottom, or sides thereof are connected to each other, and the separation distance between the current collectors may be 0.01 to 5 mm. The arrangement of the current collector may be sufficient as long as the electric field can be uniformly formed in consideration of the physical shape of the anode space. As a non-limiting example, the current collector to be injected into the positive electrode may have a structure in which a plurality of current collectors are connected to each other by a conductive member and spaced apart from each other at equal intervals. The plurality of cylinders, elliptical cylinders or triangular to octagonal polygonal collectors may have concentric structures and spaced apart arrangements. The height of the current collector may be at least a height filled with particulates in the anode space. That is, the current collector may have a structure partially embedded in the particles.

In the sodium secondary battery according to an embodiment of the present invention, the sodium ion conductive solid electrolyte may be a material used for selective conduction of sodium ions to a conventional sodium secondary battery. As a specific example, the sodium ion conductive solid electrolyte may include a sodium super ionic conductor (NaSICON), β ″ alumina, or a laminate thereof.

In the sodium secondary battery according to an embodiment of the present invention, the particulate form may contain a positive electrode active material, and the positive electrode active material (positive electrode active material particles) contained in the particulate may include nickel hydroxide. In this case, the anode reaction may be Ni (OH) ₂ ↔NiOOH.

In the sodium secondary battery according to an embodiment of the present invention, the average particle size (diameter) of the positive electrode active material contained in particulate form may be 1 μm to 100 μm. If the average particle size of the positive electrode active material is too small, less than 1 μm, the specific surface area of the positive electrode active material becomes large, but the uniform distribution of the binder is difficult, which may reduce the binding and physical stability of the particles forming the positive electrode in the battery. Excess binder may be required for the binding of P, thereby reducing the substantial surface area (particulate surface area) that can react with sodium ions. If the average particle size of the positive electrode active material is too large to exceed 100 µm, there is a risk that the battery characteristics are deteriorated by the reduction of the specific surface area of the positive electrode active material.

In the sodium secondary battery according to an embodiment of the present invention, the particulate may further contain conductive particles together with the positive electrode active material. The conductive particles form a low resistance path between the positive electrode active material and the current collector contained on the particles filling the positive electrode space to a certain height, thereby reducing the internal resistance of the battery. Specifically, the conductive particles may contain carbon, nickel, titanium, yttrium, calcium, chromium, cobalt, zinc, graphite, graphene or a mixture thereof.

Specifically, the particulate form may further contain 0.5 to 20 parts by weight of conductive particles based on 100 parts by weight of the positive electrode active material. The weight ratio of the conductive particles to the positive electrode active material is a weight ratio in which a low resistance path can be uniformly formed between the positive electrode active material and the current collector without interfering with the positive electrode reaction generated in the positive electrode active material.

The average particle size (diameter) of the positive electrode active material may be 1 μm to 100 μm, and the average particle size of the conductive particles may be 0.1 μm to 30 μm. The size of the conductive particles prevents the amount of the positive electrode active material from being filled by the conductive particles in the same volume of the positive electrode space, and reduces the amount of conductive particles in the interstitial space of the positive electrode active material. Size.

In the sodium secondary battery according to the exemplary embodiment of the present invention, the particulate form filling the positive electrode space in which the current collector is located may be bound by a binder, and the binding may be made by drying a solution binder. That is, the solution phase binder located in the inter-particle void space of the anode space may be phase-converted from the liquid phase to the solid phase by volatilization of the liquid phase (including the solvent), and may be bound between the particles and the particles and between the particles and the current collector.

More specifically, the particulate form filling the positive electrode space may be a binder between particles and between the particles and the current collector by drying of a binder injected into the positive electrode space as a solution.

With reference to the above-described manufacturing method, the particulate form filling the anode space may be a binder in the anode space by being injected into the anode space in powder form, and then added to the anode space and dried in solution.

Referring to the above-described manufacturing method, the particulate form filling the anode space may be bound in the anode space by being poured into the anode space as a slurry together with a binder dissolved in a solvent and then dried.

That is, the positive electrode according to the embodiment of the present invention may be manufactured directly in the positive electrode space.

The positive electrode according to the exemplary embodiment of the present invention may contain 0.1 to 20 parts by weight of the binder based on 100 parts by weight of the positive electrode active material. The binder content is an amount that can stably bind the particulate phase filling the anode space to a certain height while minimizing the reduction of the reactive surface area of the particulate phase. The binder may include polytetrafluoroethylene (PTFE), polyvinyl alcohol (PVA), polyolefine, polyethylene oxide (PEO) or a mixture thereof.

In addition, the positive electrode according to an embodiment of the present invention may further contain 0.1 to 10 parts by weight of a viscosity modifier based on 100 parts by weight of the positive electrode active material. Such a viscosity modifier may be a residue remaining on the positive electrode as the positive electrode is manufactured directly in the positive electrode space. Specifically, the binder solution or slurry may contain a viscosity control agent for easy introduction and uniform distribution of the above-mentioned binding solution or slurry (positive electrode active material slurry) in the positive electrode space, and when the solvent is volatilized, the viscosity control agent may be positive May remain. The viscosity modifier may be a cellulose based one or more selected from carboxymethyl cellulose (CMC), methyl cellulose, methyl cellulose, ethyl cellulose and hydroxypropyl methylcellulose (HPMC).

In the sodium secondary battery according to an embodiment of the present invention, the positive electrode may further include an electrolyte, and the empty space in which the positive electrode space is filled and left by the particle phase, that is, the space between the particles and the particle, the space between the particles and the battery case And / or the space between the particle and the current collector may be filled by the electrolyte solution. That is, the positive electrode includes a current collector located in the positive electrode space; Particulate form filling the anode space; And an electrolyte solution filling at least the inter-particle void space, wherein the particulate form may be particulate in a state bound by a binder.

The electrolyte serves to conduct sodium ions quickly and uniformly, and the electrolyte salt (sodium salt) contained in the electrolyte may include hydroxide, borate, phosphate, or a mixture thereof. Specifically, the electrolyte salt may be sodium hydroxide (NaOH), trisodium phosphate (Na ₃ PO ₄ ), sodium pyrophosphate (Na ₂ HPO ₄ ), sodium metaborate (NaBO ₂ ), borax (Na ₂ B ₄ O ₇ ), Boric acid (H ₃ BO ₃ ) or mixtures thereof. In this case, the electrolyte may include an aqueous or non-aqueous electrolyte, and the electrolyte may contain 2 to 50 wt% of an electrolyte salt.

In the sodium secondary battery according to an embodiment of the present invention, the negative electrode positioned in the negative electrode space includes a negative electrode active material used in a conventional sodium secondary battery. Specifically, the negative electrode may be a laminate in which a negative electrode active material layer is formed on the negative electrode current collector, or may be metal sodium. More specifically, in the operating state of the cell, the negative electrode may be molten sodium.

In the sodium secondary battery according to one embodiment of the present invention, the capacity of the battery can be designed by the amount of particulates filling the anode space, so that even if the anode volume of the same volume, by the degree of filling by the particulate phase Battery capacity may vary.

Accordingly, the amount of particulate matter (the height of the anode space filled by the particulate phase, or the volume of the anode space filled by the particulate phase) filling the anode space can be appropriately adjusted in consideration of the target cell design.

However, in the same volume of anode space, in terms of maximizing the capacity and charge / discharge efficiency of the battery and ensuring fast charge and discharge rate of the battery, the particulates are formed at a height corresponding to the level of molten sodium in the cathode space. Can be filled. That is, the particulate can fill the anode space at a height corresponding to at least the level of molten sodium (cathode active material) in the cathode space, it can fill the entire anode space.

5 is an example illustrating a cross section of a sodium secondary battery according to an exemplary embodiment of the present invention. FIG. 5 illustrates an example of a structure of a tubular sodium secondary battery in which a negative electrode is located at the center, but the sodium secondary battery according to the present invention may have any battery structure known in a conventional sodium sulfur secondary battery. Specifically, of course, the sodium secondary battery according to the present invention may have a structure of a tubular sodium secondary battery in which a positive electrode is located at the center, and of course, may have a flat structure.

Similar to FIG. 5, in the sodium secondary battery according to the exemplary embodiment of the present invention, a metal housing 100 corresponding to the battery case is positioned at the outermost portion, a wicking tube 420 is positioned at the center thereof, and the metal housing 100 is located at the center thereof. In the inside of the metal housing 100 from the outer side to the inside, the solid electrolyte tube 300, the safety tube 410 and the wicking tube 420 may be provided in sequence. That is, from the outside of the metal housing 100 to the inside, the solid electrolyte tube 300, the safety tube 410 and the wicking tube 420 has a concentric structure, between the metal housing 100 and the solid electrolyte tube 300 The current collector 200 may be located in the anode space. The current collector 200 may be in a rolled state as shown in FIG. 5, but a plurality of current collectors may be spaced apart from each other and positioned in the positive electrode space. The positive electrode space in which the current collector 200 is located may be filled with particulates P bound to each other by drying a binder injected into the positive electrode space in a liquid phase in the positive electrode space. The height of the anode space filled with particulate matter (P) is at least a level of molten sodium of the cathode, specifically, a level corresponding to the level of molten sodium (H) filling the void space between the wicking tube 420 and the safety tube 410. The particulate phase may be filled up to or more. In this case, the empty space remaining in the anode space and filled with particles, that is, the space between the particles and the particles, the space between the particles and the metal housing, and / or the space between the particles and the current collector may be filled with the electrolyte, and the electrolyte is located at least in the anode space. It is possible to fill the anode space with a level where all particulates can be impregnated. Although not shown in FIG. 5, the sodium battery according to the exemplary embodiment of the present invention is disposed on the metal housing 100 to have a cover and ring shape to seal the inside of the metal housing, and is located above the metal housing 100. An insulator electrically insulating between the metal housing 100 and the solid electrolyte tube 300 may be provided, and an electrode terminal positioned around an upper end of the metal housing 100 may be provided. Of course, it may include more.

Claims (25)

a) inserting a current collector into a positive electrode space partitioned from the negative electrode space by a sodium ion conductive solid electrolyte; And b) injecting an active material containing a positive electrode active material into the positive electrode space into which the current collector is inserted; Sodium secondary battery manufacturing method comprising a. The method of claim 1, Step b) b1) injecting a particulate phase containing a cathode active material and conductive particles into the anode space; And b2) putting a binder solution containing a viscosity modifier and a binder into the anode space and drying; Sodium secondary battery manufacturing method comprising a. The method of claim 1, Step b) b3) injecting and drying a slurry containing a positive electrode active material, a conductive particle, a viscosity modifier and a binder in the positive electrode space; Sodium secondary battery manufacturing method comprising a. The method of claim 1, Step a) Cylindrical metal housing, one end of which is sealed at one end and the other end is open, is located inside the metal housing, sodium ion conductive solid electrolyte tube positioned with a concentric structure sequentially from the outside of the metal housing to the inside, safety Providing a tube and a wicking tube loaded with molten sodium; And the cathode space is a space between the solid electrolyte tube and the metal housing. The method of claim 4, wherein The current collector is a method of manufacturing a sodium secondary battery wound so as to have a concentric structure with the metal housing. The method of claim 1, The current collector is a method of manufacturing a sodium secondary battery in the form of a foam (film), film (mesh), felt (felt) or porous foil (perforated film). The method of claim 1, The current collector is a method of manufacturing a sodium secondary battery at least one selected from carbon, nickel, titanium, yttrium, calcium, chromium, cobalt, zinc, graphite and graphene. The method of claim 3, The conductive particle is a method of manufacturing a sodium secondary battery comprising carbon, nickel, titanium, yttrium, calcium, chromium, cobalt, zinc, graphite, graphene or a mixture thereof. The method of claim 8, The particulate phase is a method of manufacturing a sodium secondary battery containing 0.5 to 20 parts by weight of conductive particles based on 100 parts by weight of the positive electrode active material. The method of claim 1, The cathode active material is a method of manufacturing a sodium secondary battery containing nickel hydroxide (Ni (OH) ₂ ). The method of claim 2, The binder solution is a viscosity of the sodium secondary battery manufacturing method of 0.01 P to 10,000 P. The method of claim 3, The viscosity of the slurry is 0.01 P to 10,000 P manufacturing method of the sodium secondary battery. The method according to claim 2 or 3, The viscosity modifier includes a cellulose system selected from at least one selected from carboxymethyl cellulose (CMC), methyl cellulose, methyl cellulose, ethyl cellulose and hydroxypropyl methylcellulose, and the binder The polytetrafluoroethylene (PTFE; polytetrafluoroethylene), polyvinyl alcohol (PVA; polyvinyl alcohol), polyolefin (polyolefine), polyethylene oxide (PEO; polyethylen oxide) or a mixture thereof. The method of claim 2, The binder solution is a method of manufacturing a sodium secondary battery containing a binder of 0.1 to 20% by weight. The method of claim 3, The slurry is a method of manufacturing a sodium secondary battery containing 0.1 to 20 parts by weight of conductive particles, 0.1 to 10 parts by weight of a viscosity modifier and 0.1 to 20 parts by weight of a binder based on 100 parts by weight of the positive electrode active material. The method of claim 1, After step b), c) injecting an electrolyte into the cathode space. Sodium ion conductive solid electrolyte partitioning the cathode space and the anode space; A sodium-containing negative electrode positioned in the negative electrode space; And An anode including a current collector positioned in the anode space and a cathode filled in a cathode space in which the collector is located, the particulate containing a cathode active material; Sodium secondary battery comprising a. The method of claim 17, Particles filling the positive electrode space is a sodium secondary battery that is bound by the drying of a binder injected into the positive electrode space in the form of a solution. The method of claim 17, The particulate form is a sodium secondary battery further comprises conductive particles. The method of claim 19, The particulate form is a sodium secondary battery containing 0.5 to 20 parts by weight of conductive particles based on 100 parts by weight of the positive electrode active material. The method of claim 17, The cathode active material includes sodium hydroxide (Ni (OH) ₂ ). The method of claim 17, The cathode is a sodium secondary battery is molten sodium. The method of claim 22, And the particulate phase fills the positive electrode space to a height corresponding to the level of the molten sodium in the negative electrode space. The method of claim 17, The sodium secondary battery has a cylindrical metal housing, a sodium ion conductive solid electrolyte tube, a safety tube, and a wicking tube in which molten sodium is located, which is located inside the metal housing and has a concentric structure sequentially from the outside to the inside of the metal housing. And a positive electrode space is a space between the solid electrolyte tube and the metal housing. The method of claim 17, The empty space of the cathode space filled with the particulate is filled with an electrolyte solution.

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