JP2002252027A - Sodium sulfur battery system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a suitable sodium sulfur battery system to use for electric power storage equipment, an electric automobile, or the like, which has high safety and a simplified system structure by preventing leakage of sulfur dioxide gas to the exterior which occurs when sodium sulfur battery is damaged. SOLUTION: Absorbent of sulfur dioxide is prepared to exterior of the sodium sulfur battery containing a negative-electrode room, which contains sodium, a positive-electrode, which contains an active material, which consists of sulfur or/and sodium polysulfide, and a solid electrolyte, which is separated between the above positive-electrode room/the negative-electrode room.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sodium-sulfur battery system suitable for use in power storage devices, electric vehicles, and the like.

[0002]

2. Description of the Related Art A negative electrode active material, sodium, is placed in a negative electrode chamber.
Sodium sulfur with a structure in which the positive electrode chamber is filled with positive electrode active material sulfur or sodium polysulfide, and the space between the negative electrode chamber and the positive electrode chamber is separated by a β-type or β ″ -type beta alumina ceramic solid electrolyte bag tube or solid electrolyte flat plate Batteries are attracting attention because of their long life and high energy density, and are expected to be used in power storage devices and electric vehicles suitable for load leveling, which store nighttime power and use it during the day. It is important to take advantage of the difference in electricity rates between day and night to promote the application to private power storage devices and electric vehicles. It is important to take measures against the problem that the sulfur dioxide gas generated sometimes leaks out of the sodium-sulfur battery system.

[0003] Regarding the safety of sodium-sulfur battery,
Various measures have been taken against the battery structure to ensure the stability of the positive and negative electrode containers against external short circuits and damage to the solid electrolyte.However, measures should be taken in case the positive and negative electrode containers are damaged. It is also important. To solve this problem, for example, JP-A-3-283272 and JP-A-6-689.
As disclosed in Japanese Patent Publication No. 05-2005 and the like, a dry container or the like is filled in a heat-insulating container such as a vacuum insulated container that houses a sodium container and is kept at about 300 ° C. to move and activate the active material released from the battery. Methods have been proposed to prevent reactions between substances. Although this method is effective in suppressing chain breakage of adjacent batteries, sulfur and sodium polysulfide, which are the positive electrode active materials released from the damaged battery, react with air in the heat insulation container and generate sulfur dioxide gas. Is insufficient as a countermeasure against the problem of leakage from the thermal insulation container. In addition, sulfur dioxide gas is toxic, and if it leaks out of the heat insulation container and flows out, there is a possibility that problems such as obstacles to the human body may occur. On the other hand, Japanese Patent Application Laid-Open Nos.
In JP-A-254438 and JP-A-8-250152, the inside of the heat insulating container is hermetically or semi-hermeticly sealed, and the inside is filled with an inert gas such as an argon gas as a heat insulating gas, or an oxygen removing means is provided. There has been proposed a method of preventing the generation of sulfur dioxide gas when the battery is broken by providing the battery. However, in the case of a sodium-sulfur battery, when the temperature rises and falls between the battery operating temperature of about 300 ° C. and room temperature, the gas inside the heat retaining container thermally expands and contracts,
Since stress is applied to the sealed thermal insulation container, it is necessary to make the thermal insulation container a high-strength structure that maintains sufficient mechanical strength,
In the latter case, there is a problem that the structure of the heat retaining container becomes complicated, for example, it is necessary to provide an oxygen removing means. In addition, when a closed structure is used as the heat insulating container, there is a problem that it takes time to take the sodium-sulfur battery into and out of the heat insulating container. Further, Japanese Patent Application Laid-Open No. 6-104007 proposes a method in which a gas purification device is attached to an exhaust pipe connected to a heat retaining container, and sulfur dioxide generated when the battery is damaged is purified by the gas purification device. However,
In this case, since it is necessary to attach an exhaust device and a gas purification device to the heat retaining container, the system structure becomes complicated, the volume of the system increases, and the place where the sodium sulfur battery system can be installed is limited. There is.
As described above, in the conventional method, it has been difficult to achieve both the measures against leakage of sulfur dioxide gas generated when the battery is damaged and the simplification of the heat insulation container structure and the system structure.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned disadvantages of the prior art and to provide a simple thermal insulation container structure or a system structure that allows sulfur dioxide gas to leak out of the system even if a battery is damaged. An object of the present invention is to provide a highly safe sodium-sulfur battery system that does not cause any problems.

[0005]

In a first sodium-sulfur battery system of the present invention, a negative electrode chamber containing sodium, a positive electrode chamber containing a positive electrode active material comprising sulfur and / or sodium polysulfide, and It is characterized in that a sulfur dioxide absorbent is provided outside a sodium-sulfur battery including a solid electrolyte in which a negative electrode chamber / a positive electrode chamber is separated. Further, the second sodium-sulfur battery system of the present invention separates a negative electrode chamber containing sodium, a positive electrode chamber containing a positive electrode active material composed of sulfur or / and sodium polysulfide, and the negative electrode chamber / positive electrode chamber. A sodium-sulfur battery containing the solid electrolyte thus obtained is housed in a heat insulation container, and a sulfur dioxide absorbent is provided inside or / and at the opening of the heat insulation container. Further, in the third sodium-sulfur battery system of the present invention, a negative electrode chamber containing sodium, a positive electrode chamber containing a positive electrode active material composed of sulfur and / or sodium polysulfide, and a space between the negative electrode chamber and the positive electrode chamber are separated. The sodium-sulfur battery containing the solid electrolyte thus obtained is housed in a heat-insulating container, and one or more of the heat-insulating containers are placed in a fire-resistant structure container such as a cubicle, and the inside or / and the opening of the fire-resistant structure container It is characterized by providing a sulfur dioxide absorbent.

Here, in the first, second and third sodium-sulfur battery systems of the present invention, the absorbent is an alkali metal oxide or hydroxide, or an alkaline earth metal oxide or hydroxide. Or a compound of an alkali metal oxide, a hydroxide and an oxide of silicon, a hydroxide or an oxide of zirconium, or a hydroxide. Particularly, the absorbent is calcium or / and magnesium. It is desirable to use hydroxide or oxide of magnesium. Further, it is desirable that the absorbent is held by an inorganic porous material or an organic porous material,
It is particularly desirable that the porous material is a heat insulator for a sodium-sulfur battery.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIG. 1 shows a structural example of a first sodium-sulfur battery system of the present invention. In the figure, a sodium-sulfur battery 10 includes a solid electrolyte 1, a negative electrode container 2, a positive electrode container 3, sodium 4 contained in a negative electrode chamber 20 composed of a solid electrolyte and a negative electrode container, and a solid electrolyte and a positive electrode container. The sulfur contained in the configured cathode chamber 30 and / or
And a positive electrode active material 5 composed of sodium polysulfide. Here, the solid electrolyte 1 is usually formed of a bag tube or a flat plate of a sodium ion conductor made of β-alumina of β-type or β ″ -type, and the solid electrolyte 1 separates between the negative electrode chamber / the positive electrode chamber. Also, the negative electrode chamber 2
A sodium container 21 is provided in 0, and sodium stored in the sodium container is supplied to the surface of the solid electrolyte 1 through a through hole 6 provided in a lower portion. In addition,
In this figure, the negative electrode container 2 and the sodium container 21 are connected, but it is also possible to separate them. on the other hand,
In the positive electrode chamber 30, a porous conductive material 7 made of an aggregate of carbon fibers and carbon particles and a holding material 8 of sodium polysulfide made of an aggregate of fibers and particles of ceramics and glass are provided. Is impregnated in a porous conductive material or a holding material, and the battery reaction proceeds. Further, an insulating material 9 is joined to an end portion of the solid electrolyte 1, and the insulating material is joined to the negative electrode container 2 and the positive electrode container 3, so that the battery has a hermetically sealed structure. Are electrically insulated. Here, a ceramic such as α-alumina or magnesium aluminum spinel is used as the insulating material 9, which is not shown, but is glass-bonded to the end of the solid electrolyte or is integrally sintered. In addition, the negative electrode container 2
And the positive electrode container 3 are made of Al alloy, Fe alloy, SUS, or a metal material having a corrosion-resistant layer mainly composed of Cr, Mo, Ti, Si, C, etc. on the surface thereof, or a clad material of Al alloy and SUS. Although not shown, Al or Al
An alloy is generally used as a bonding material with the insulating material 9, and is heated to a liquidus temperature or a solidus temperature or lower of the bonding material, and is generally bonded by a pressure bonding method in which pressure bonding is performed. Further, FIG.
In the structure (1), the storage container 11 is provided around the sodium-sulfur battery 10, and the storage container 11 and the sodium-sulfur battery 10 are filled with the sulfur dioxide absorbent 12. Here, as the storage container 11, Al alloy or Fe
A metal container made of an alloy, SUS, or the like may be used.
A non-metal container such as glass or ceramic may be used. Although not shown, when a metal container is used as the storage container 11, the storage container 11 may be partially joined to the positive electrode container 3 and used as the positive electrode.

As described above, by providing the sulfur dioxide absorbent 12 outside the sodium-sulfur battery and surrounding the positive electrode container 3 with the absorbent 12 and the storage container 11, the battery may be damaged and Even if sulfur as an active material leaks out of the container 3 and reacts with air to generate sulfur dioxide gas, the sulfur dioxide gas is absorbed by the absorbent 12 to prevent the sulfur dioxide gas from leaking to the outside. Can be. In addition,
For this purpose, it is desirable to provide the absorbent 12 at least at the opening of the storage container 11 to prevent the sulfur dioxide gas from leaking from the storage container to the outside. Although not shown, the leakage of sulfur dioxide gas can also be prevented by holding the absorbent 12 with a porous material and surrounding the sodium sulfur battery 10 instead of providing a storage container.

Here, as the sulfur dioxide absorbent 12, compounds such as oxides or hydroxides of alkali metals,
Alternatively, it is desirable to use a compound such as an oxide or hydroxide of an alkaline earth metal, or a compound of an oxide or hydroxide of an alkali metal and an oxide or hydroxide of silicon. Further, a compound of an oxide or hydroxide of an alkali metal and an oxide or hydroxide of zirconium can also be used. These compounds have alkaline properties and can easily react with sulfur dioxide gas having acidic properties to absorb the sulfur dioxide gas. In addition, absorbent 12
May be filled into the storage container 11 by using powders of these compounds, or the storage container 1 (not shown).
1 may be filled with an inorganic porous material, and a material in which the absorbent is held by the porous material may be used, for example, by mixing these compounds with the porous material. In particular, when compounds of sodium or potassium are used as the absorbent 12, these compounds may corrode or dissolve the positive electrode container 3 or the metal storage container 11, so that inorganic compounds such as glass fibers may be used. It is desirable to avoid direct contact between the sodium or potassium compound and the positive electrode container or the storage container by using a porous material. Further, when the storage container is filled with the material held by the porous material as the absorbent 12, the positive electrode container 3 and the storage container 11 are compared with the case where the powder of the compound as the absorbent is directly charged.
There is also an advantage that the stress based on the difference in thermal expansion between the two is alleviated by the low rigidity of the porous material and the mechanical reliability of the battery is improved. Although it is conceivable to use an organic substance such as a polymer fiber as the porous material, in the case of a sodium-sulfur battery, since the battery operating temperature is relatively high, the absorbent 12 is provided adjacent to the sodium-sulfur battery, When the absorbent is installed in a heat-insulating container containing a sodium-sulfur battery, it is desirable to use an inorganic porous material such as glass fiber.

Here, since the sodium-sulfur battery is generally housed in a heat-insulating container and operated at a temperature of about 300 ° C. or higher, compounds such as oxides and hydroxides of alkali metals as the absorbent 12; Or an oxide of an alkali metal such as lithium metasilicate, sodium metasilicate, potassium metasilicate, lithium metazirconate, sodium metazirconate, potassium metazirconate, an oxide of hydroxide and silicon, a hydroxide, Even if a compound of zirconium oxide and hydroxide is used, there is no problem that these compounds are dissolved by moisture in the air. However, when the operation of the battery is stopped for a long period of time, these compounds are dissolved by moisture entering from outside air, and especially in the case of compounds such as oxides and hydroxides of alkali metals, the cathode container 3 There is a possibility that the container may be corroded by contact with the metal container 11 or metal. In order to avoid this problem, it is desirable to use alkaline earth metal oxides or hydroxides as the absorbent, and in particular, calcium and magnesium hydroxides and magnesium oxides have low solubility in water. It is particularly desirable to use it as an absorbent. When calcium oxide is used, the possibility of absorbing and dissolving water is small,
It is necessary to select the storage container 12 and the material of the porous material contained in the storage container in consideration of the influence of heat generation when generating hydroxide by reacting with moisture.

FIG. 2 shows an example of the structure of the second sodium-sulfur battery system of the present invention, and the components denoted by the same reference numerals as those in FIG. 1 represent the same components. This figure shows the structure of a module 40 in which a sodium-sulfur battery 10 is housed in a heat insulation container 13 formed of a vacuum heat insulating container. here,
The sodium-sulfur battery is electrically connected between the batteries by a bus bar 14, and is also electrically connected to an external circuit. On the other hand, the lower portion of the sodium-sulfur battery 10 and the heat insulating container 1
3, an insulating plate 15 such as a mica plate is provided.
Both are electrically separated. In addition, the fire-extinguishing powder 16 such as dry sand is filled in the thermal insulation container, and when the battery is damaged and the active material leaks from the battery, the movement of the active material is controlled to prevent the adjacent battery from being damaged. are doing. Although not shown, a heater for increasing the battery temperature is provided inside the heat retaining container. Further, the sodium-sulfur battery 10 can be laid down and housed in the heat insulation container 13.

In the structure of FIG. 2, the sulfur dioxide absorbent 12 is installed on the inner side surface of the heat retaining container 13, and
The absorbent 12 is also provided at the opening of the heat retaining container, that is, at the interval between the main body 131 and the lid 132 of the heat retaining container, whereby the battery is damaged and sulfur flows out of the battery, When the sulfur dioxide gas is generated by reacting with the air, the sulfur dioxide gas is absorbed by the absorbent 12 and the leakage of the sulfur dioxide gas to the outside of the heat insulation container is prevented. For this purpose, as shown in the figure, it is desirable to install the absorbent 12 in the space between the main body 131 and the lid 132 of the heat retaining container. Further, as the absorbent 12, a compound such as an oxide or a hydroxide of an alkali metal, a compound such as an oxide or a hydroxide of an alkaline earth metal, or an oxide or a hydroxide of an alkali metal and silicon By using oxides, hydroxides, compounds of zirconium oxides and hydroxides and holding them with a porous material, sulfur dioxide gas penetrates into the absorbent through the porous material and While being absorbed by the compound, there is no danger that the above-mentioned compound constituting the absorbent is held by the porous material and falls into or out of the heat retaining container, and the reliability of the structure for installing the absorbent in the module 40 is high. Further, the main body 131 of the heat insulating container
And the lid 132 are separated from each other, and the inside of the heat insulating container is not airtightly sealed. Therefore, when the temperature rises and falls between room temperature and the battery operating temperature, air moves into and out of the heat insulating container 40 to be sealed. The gas inside expands like a warm insulated container,
There is no problem that stress is applied to the heat insulation container due to heat shrinkage, and there is also an advantage that the mechanical reliability of the heat insulation container is high. For this purpose, it is desirable to use at least the absorbent 12 provided at the interval between the main body 131 and the lid 132 of the heat retaining container, which is held by a porous agent such as ceramic fiber or glass fiber. This facilitates the smooth movement of air into and out of the heat retaining container during temperature rise and fall.

Further, since it is not necessary to attach an oxygen removing means or a gas purifying device to the heat retaining container, the structure of the sodium-sulfur battery system is reduced in size and simplified, and the range of the installable place is widened. It also has the advantage that it is particularly suitable for medical applications.

Although not shown, the fire extinguishing powder 16
A sulfur dioxide absorbent 12 may be mixed and used, or in some cases, the extinguishing powder 16 may be filled with the absorbent 12 instead. However, in this case, a compound such as an oxide or hydroxide of an alkaline earth metal, an oxide of an alkali metal, It is desirable to use a compound of a hydroxide and an oxide of silicon, an oxide of a hydroxide or zirconium, or a hydroxide. When a compound such as an oxide or a hydroxide of a sodium metal or a potassium metal is used, it is desirable to protect the outer surface of the sodium-sulfur battery 10 and the inner surface of the heat retaining container 13 with a porous material or the like. Further, as shown in FIG. 2, when the absorbent 12 is provided in the space between the main body 131 and the lid 132 of the heat retaining container, at least the absorbent near the outer side is made of an oxide or hydroxide of alkaline earth metal. It is desirable to use a substance, particularly a hydroxide of calcium or magnesium or an oxide of magnesium. In this way, even if air at a temperature close to room temperature comes into contact with the absorbent, there is no danger of the absorbent being dissolved by moisture contained in the air, and the reliability of the safety structure of the module 40 is high.

FIG. 3 shows an example of the structure of the third sodium-sulfur battery system of the present invention, and the components denoted by the same reference numerals as those in FIG. 2 represent the same components. This figure also shows the module 4 in which the sodium-sulfur battery 10 is stored in the heat retaining container 13.
Although the structure of No. 0 is shown, the heat retention container is provided with a cover 18 made of a metal plate on a main body 131 made of a vacuum heat insulating container, and a sulfur dioxide absorbent 12 provided below the cover. In addition, as the absorbent, a compound such as an oxide or a hydroxide of an alkali metal or an oxide or a hydroxide of an alkaline earth metal is used, and is held by a porous material. For example, a heat insulating container is formed using a heat insulating material such as rock wool. In addition, a through hole 19 is provided in the metal plate constituting the lid 18 to connect the bus bar 14 to the outside, and a heater 17 is provided inside the heat retaining container 13. By using such a structure, it is possible to reduce the cost of the heat insulation container as compared with a structure in which the heat insulation container 12 is constituted only by the vacuum insulation container as shown in FIG. It is. In some cases, the main body 13 of the heat retaining container can also be made of a metal plate and a heat insulating material. In addition, by installing the absorbent 12 below the lid, which is the opening of the heat retaining container,
Even if the battery is damaged and sulfur dioxide gas is generated, it is possible to prevent the sulfur dioxide gas from leaking to the outside of the thermal insulation container.

FIG. 4 shows an example of the structure of the fourth sodium-sulfur battery system of the present invention, and the components denoted by the same reference numerals as those in FIG. 2 indicate the same parts. This figure shows a structure in which a module 40 is filled in a refractory structure container 50 such as a cubicle, and the refractory structure container is provided with a main body 31, a door 32, a ventilation port 34, and a lid 35. Also,
The modules 40 are supported by shelves 36 and are stacked and filled in a refractory container. Further, a through hole 33 is provided on the side of the main body and the door of the fireproof structure container, and air flows in and out through the through hole and the ventilation port, whereby the temperature inside the fireproof structure container is controlled. I have.

In this figure, the main body 3 of the refractory structure container is shown.
The sulfur dioxide absorbent 12 is provided on the side surfaces of the door 1 and the door 32 and on the ventilation port 34. If the battery is damaged and sulfur dioxide gas leaks from the module, the sulfur dioxide gas is absorbed by the absorbent. The absorption prevents the sulfur dioxide gas from leaking out of the fire-resistant structure container 50. It is desirable to use a material held by a porous material as the absorbent 12, so that the installation position of the absorbent is fixed, and the problem of the absorbent falling to the lower part can be prevented. The movement of the air through the ventilation holes 33 and the ventilation openings 34 proceeds smoothly, and the temperature control inside the fireproof structure container becomes easy. further,
In this structure, since the absorbent 12 comes into contact with the outside air, the compound constituting the absorbent is desirably a calcium or magnesium hydroxide or a magnesium oxide compound having low solubility in water. Further, since the temperature of the air that comes into contact with the absorbent is near room temperature, either an inorganic substance or an organic substance may be used as the porous material. In addition,
In general, an organic porous material is lighter and cheaper than an inorganic porous material. Therefore, it is desirable to use an organic porous material in order to spread the sodium-sulfur battery system by reducing the cost. On the other hand, in order to secure the fire resistance of the sodium sulfur system, it is necessary to use an inorganic porous material. In addition, if this structure is used, the leakage of sulfur dioxide gas can be prevented without attaching a gas purifying device to the refractory structure container, so that the system structure is downsized and simplified, and the range of installation locations can be widened. There are also practical advantages.

As described above, by using the sodium-sulfur battery system of the present invention, the battery may be damaged,
When the sulfur dioxide gas is generated, the absorbent 12 absorbs the sulfur dioxide gas and prevents leakage of the sulfur dioxide gas to the outside of the system, so that the sodium dioxide is high in safety and suitable for application to civil use. A sulfur battery system is realized. Furthermore, by using a material held by a porous material as the absorbent, the mechanical reliability of the absorbent is improved, and the movement of air through the absorbent proceeds smoothly,
There are advantages that the temperature control of the sodium-sulfur battery system is facilitated and reliability is improved. Further, since it is not necessary to hermetically seal the heat insulating container 13 or to attach an oxygen removing means or a gas purifying device to the heat insulating container, the mechanical reliability of the heat insulating container is high, and the system structure is downsized and simplified. There is also an advantage that the range of the installation place can be expanded.

As a specific example, as shown in FIG. 1, a cylindrical bag tube made of lithium-doped β ″ alumina sintered body is used as the solid electrolyte 1, an insulating material 9 made of α-alumina sintered body ring and a solid electrolyte Further, an aluminum alloy was used for the negative electrode container 2 and the sodium container 21, and a chromium alloy was sprayed or plated on the inner surface of the aluminum alloy for the positive electrode container 3. The surface and the ends of the negative electrode container and the positive electrode container
-Thermal bonding was performed via an Si alloy. Further, the negative electrode chamber 2
0 is filled with liquid sodium 4 and Ar gas to seal the negative electrode container 2, and the inside of the positive electrode chamber 30 is made of a porous conductive material 7 made of carbon fiber mat and sodium polysulfide made of alumina fiber. The positive electrode active material 5 composed of the holding material 8 and sulfur was filled, and the positive electrode container 3 was sealed to produce a sodium-sulfur battery 10. Next, the sodium-sulfur battery or, as shown in FIG.
Around calcium hydroxide 12 and SU
The module 40 was prepared by housing the sodium-sulfur battery provided with the S-made storage container 11 in the heat-insulating container 13 composed of a SUS vacuum heat-insulating container as shown in FIG. As shown in FIG. 2, calcium hydroxide as an absorbent 12 is installed and held in rock wool, and an insulating plate 15 made of mica plate, a fire extinguishing powder 16 made of dry sand, and Although not shown, a heater and a temperature sensor for maintaining the battery temperature are provided.
The batteries are connected by a bus bar 14, and the bus bar is connected to an external circuit through the interior of the absorbent 12 provided between the main body 131 and the lid 132 of the heat insulating container. Is electrically insulated by the rock wool holding the absorbent 12.

The obtained module 40 is housed in a cubicle provided with a sulfur dioxide gas detector therein, and the temperature is raised and lowered at least 30 times between room temperature and the battery operating temperature of 330 ° C. Since the air did not move into and out of the heat insulating container and the problem of stress application to the heat insulating container did not occur, the problem of damage to the heat insulating container 13 did not occur at all. Also,
When the current is forcibly applied to the battery from the outside to damage the solid electrolyte 1, and the temperature of the battery is increased to peel off the joint between the positive electrode container 3 and the insulating material 9 to allow sulfur to flow out of the battery. In the above, sulfur dioxide gas generated by the reaction of sulfur with air reacted with calcium hydroxide as the absorbent 12 to generate calcium sulfite. As a result, the sulfur dioxide gas was absorbed into the absorbent 12, and the sulfur dioxide gas did not leak out of the module 40, and the safety of the sodium sulfur battery system was ensured.

[0022]

According to the present invention, it is possible to prevent the sulfur dioxide gas generated when the sodium-sulfur battery is damaged from leaking to the outside, so that the safety is high and the system structure is simplified. A sulfur battery system is realized.

[Brief description of the drawings]

FIG. 1 is a structural diagram showing a structural example of a sodium-sulfur battery system of the present invention.

FIG. 2 is a structural diagram showing a structural example of a sodium-sulfur battery system of the present invention.

FIG. 3 is a structural diagram showing a structural example of a sodium-sulfur battery system of the present invention.

FIG. 4 is a structural diagram showing a structural example of a sodium-sulfur battery system of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Solid electrolyte, 2 ... Negative electrode container, 3 ... Positive electrode container, 4 ... Sodium, 5 ... Positive electrode active material, 10 ... Sodium sulfur battery, 12 ... Absorbent, 13 ... Heat insulation container, 20 ... Negative electrode chamber, 3
0: Positive electrode chamber, 40: Module, 50: Refractory structure container.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Manabu Gakusho 3-1-1, Sachimachi, Hitachi-shi, Ibaraki Pref. Nuclear Power Division, Hitachi, Ltd. 1-chome F-term in the Nuclear Power Division of Hitachi, Ltd. (Reference) 5H029 AJ12 AK05 AL13 AM15 BJ02 BJ22 BJ23 BJ25 BJ27 DJ02 DJ10 DJ13 DJ16 EJ03 EJ05 EJ12

Claims (7)

[Claims] 1. A sodium-sulfur battery comprising a negative electrode chamber containing sodium, a positive electrode chamber containing a positive electrode active material comprising sulfur and / or sodium polysulfide, and a solid electrolyte separated between the negative electrode chamber and the positive electrode chamber. A sodium-sulfur battery system characterized in that a sulfur dioxide absorbent is provided outside of the battery. 2. A sodium-sulfur battery including a negative electrode chamber containing sodium, a positive electrode chamber containing a positive electrode active material comprising sulfur and / or sodium polysulfide, and a solid electrolyte separated between the negative electrode chamber and the positive electrode chamber. Is stored in a heat insulation container, and a sulfur dioxide absorbent is provided in the inside and / or the opening of the heat insulation container. 3. A sodium-sulfur battery including a negative electrode chamber containing sodium, a positive electrode chamber containing a positive electrode active material composed of sulfur and / or sodium polysulfide, and a solid electrolyte separated between the negative electrode chamber and the positive electrode chamber. Is stored in a heat-insulating container, and one or more of the heat-insulating containers are installed in a fire-resistant structure container such as a cubicle, and the inside of the fire-resistant structure container or /
And a sulfur dioxide absorbent in the opening. 4. The absorbent according to claim 1, wherein said absorbent is an oxide or hydroxide of an alkali metal, an oxide or hydroxide of an alkaline earth metal, or an oxidization of an alkali metal. A sodium-sulfur battery system characterized in that it is a compound of a substance, an oxide of hydroxide and silicon, an oxide of hydroxide or zirconium, or a compound of hydroxide. 5. The sodium-sulfur battery system according to claim 1, wherein the absorbent is a hydroxide of calcium and / or magnesium or an oxide of magnesium. 6. A sodium-sulfur battery system wherein the absorbent according to claim 1 is held by an inorganic porous material or an organic porous material. 7. A sodium-sulfur battery system according to claim 6, wherein said porous material is a heat-retaining material for a sodium-sulfur battery.