JP3416607B2 - Positive electrode collector for sodium-sulfur battery and sodium-sulfur battery using the same - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to sodium-sulfuric acid.
Positive battery current collector for yellow battery and sodium-sulfur using the same
Regarding batteries. More specifically, sodium-sulfur battery
When used for excellent charging recovery and long-term durability,
And to provide a sodium-sulfur battery with low internal resistance
The positive electrode current collector for sodium-sulfur batteries
In addition, using this, charge recovery and long-term durability
Excellent in sodium-sulfur battery with low internal resistance
Concerned.

[0002]

2. Description of the Related Art Sodium-sulfur batteries (hereinafter referred to as "NA
S battery ". ) Is a sealed hot secondary battery to operate at a high temperature of 300 to 350 ° C., as an anode active material
Of sodium and sulfur as a positive electrode active material are separately housed by a solid electrolyte (for example, β-alumina, β ″ -alumina, etc.) having a function of selectively permeating sodium ions.

For example, in a NAS battery 1 shown in FIG. 1, a bottomed cylindrical solid electrolyte tube 13 is disposed inside a hollow cylindrical positive electrode container 9, and a negative electrode active material is used inside the solid electrolyte tube 13.
All sodium 2 is stored , and the positive electrode is collected outside.
Sulfur 4 as the positive electrode active material impregnated in collector 11, negative
It is obtained and stored isolated from sodium 2 as active material. In FIG. 1, reference numeral 3 is an insulator phosphorus.
Reference numeral 5 indicates a cylindrical metal fitting, reference numeral 7 indicates a negative metal fitting, reference numeral
Reference numerals 10 respectively indicate constrictions. Solid electrolyte tube 13
Is joined to the positive electrode container 9 via the insulator ring 3 made of α-alumina or the like and the cylindrical metal member 5 so that the positive electrode side and the negative electrode side are electrically insulated.

The NAS battery 1 has a negative electrode active material when discharged.
2 as an electron emits an electron to the external circuit to become a sodium ion, permeates through the solid electrolyte tube 13 and moves to the positive electrode side, and reacts with sulfur 4 as a positive electrode active material and an electron supplied from the external circuit. A voltage of about 2 V is generated by generating sodium polysulfide.

On the other hand, at the time of charging, by applying a voltage from an external circuit, sodium polysulfide releases electrons to the external circuit to generate sulfur and sodium ions, which permeate the solid electrolyte tube 13 and move to the negative electrode side. The sodium ion is reacted with an electron supplied from an external circuit to be electrically neutralized, thereby converting electric energy into chemical energy.

Sulfur 4 as a positive electrode active material for NAS batteries
Since is an insulator, it is common to dispose a positive electrode current collector 11 for the purpose of ensuring conduction between the positive electrode and the negative electrode and reducing the internal resistance of the battery. The positive electrode current collector 11 is a member made of a felt material made of conductive carbon fiber or graphite fiber, impregnated with sulfur 4 as a positive electrode active material, and the inner peripheral surface of the positive electrode container 9 and the solid electrolyte tube 13. by arranging so as to contact both of the outer peripheral surface, conduction between the positive electrode and the negative electrode can be secured, also the internal resistance of the battery is reduced.

Furthermore, the cathode current collector 11 used in the NAS battery 1, the base material constituting the positive electrode collector 11, the outer peripheral surface and one front surface of the abutting of the solid electrolyte tube 13, alpha-alumina, A high resistance layer made of insulating material such as glass is coated.
Has been . The high resistance layer lowers the conductivity in the vicinity of the contact surface between the solid electrolyte tube 13 and the positive electrode current collector 11, so that electrons are transferred and received only in the vicinity of the contact surface between the solid electrolyte tube 13 and the positive electrode current collector 11 during charging. It is possible to avoid the reaction from taking place. Therefore, sulfur, which is an insulator, is concentrated in the relevant portion and the charge recovery property is lowered due to the increase in the internal resistance of the battery as the charging reaction proceeds (despite the fact that sodium polysulfide remains. It is possible to prevent the phenomenon that the charging reaction does not proceed and the charging is not completed.

[0008]

The object of the invention is to, however, the base material
Even when a positive electrode current collector having a high resistance layer coated on one surface is provided , the charge recovery property is lowered, or conversely, the internal resistance of the battery is increased, and the sodium ion positive electrode side during discharge Occasionally there was a case where movement to was hindered.
In particular, in recent years, as the size of the NAS battery has increased, the thickness of the positive electrode current collector has increased to about 15 mm, and the travel distance of sodium polysulfide during charging has also become longer. Is required to be balanced in a high dimension.

The present invention has been made in view of the above problems of the prior art, and an object thereof is to recover charge when used in a sodium-sulfur battery.
And long-term durability with low internal resistance
Sodium-sulfuric acid capable of providing um-sulfur battery
A positive electrode current collector for a yellow battery, further comprising:
Excellent electrical recovery and long-term durability, and low internal resistance
It is to provide a sodium-sulfur battery .

[0010]

Means for Solving the Problems As a result of intensive investigations by the present inventors, a positive electrode current collector for sodium-sulfur batteries was constructed.
The present invention has been completed by finding that the problems of the above-mentioned conventional techniques can be solved by precisely controlling the structure of the high resistance layer coated on one surface of the base material .

[0011] That is, according to the present invention, as the positive electrode active material
Of the sodium-sulfur battery with all sulfur impregnated
Touch both the inner surface of the positive electrode container and the outer surface of the solid electrolyte tube.
The felt-like base material made of carbon fiber or graphite fiber , which is disposed so as to be in contact with the base material, and the glass fiber , which covers one surface of the base material , is punched into the base material by needle punching. sodium and a high resistance layer formed write or be in - a cathode current collector for sulfur battery, relative to the total weight of the base material, hitting the inside of the substrate
The quality of the glass fibers that compose the high resistance layer
Ratio of the amount is, Ri near the range of 2 to 15 wt%, the high resistance
The glass fiber constituting the anti-layer, inside the substrate,
Driven to a depth of 70-100% of the thickness of the substrate
And 20 to 85% of one surface of the substrate is
Nato characterized by being coated with a high resistance layer
A positive electrode current collector for a lithium-sulfur battery is provided.

[0012]

Further, according to the present invention, a bottomed cylindrical solid electrolyte tube is disposed inside a hollow cylindrical positive electrode container,
Sodium as a negative electrode active material in the interior of the solid electrolyte
Is stored , and sulfur as the positive electrode active material is contained outside the solid electrolyte, and the solid is formed on the inner peripheral surface of the positive electrode container and the solid.
It was arranged so as to come into contact with both the outer peripheral surface of the electrolyte tube
As a negative electrode active material in a state of being impregnated with a positive electrode current collector
Sodium made are housed is isolated from the sodium -
A sulfur battery, wherein a positive electrode collector, the above diisocyanato
Potassium - cathode current collector for sulfur batteries, the front surface of one comprising coated is used is disposed so as to contact the outer peripheral surface of the solid electrolyte tube by the high-resistance layer of the substrate < A sodium-sulfur battery is provided.

[0014]

DETAILED DESCRIPTION OF THE INVENTION The sodium-sulfur battery of the present invention
The positive electrode current collector for use is one in which a specific high resistance layer is coated on one surface of a base material. Such sodium-sulfur
According to the positive electrode current collector for ponds, it is possible to provide a NAS battery having excellent charge recovery and low internal resistance .

Collection of Positive Electrodes for Sodium-Sulfur Battery of the Present Invention
Collector (hereinafter, simply referred to as "current collector".) Has a felt-like base material made of carbon fibers or graphite fibers, on one front surface of its high resistance formed by implanting glass fibers by needle punching Basic structure consisting of layers
I am trying .

In the current collector, in addition to being excellent in insulating property, glass fiber having a high affinity for sodium polysulfide is used as a material for the high resistance layer, and the glass fiber has high conductivity and a positive electrode. Carbon fiber or graphite fiber, which has excellent corrosion resistance to sulfur as an active material , is formed into a high-resistance layer by needle punching from one surface side of the felt-shaped substrate, and one surface of the substrate is formed by the high-resistance layer. Coating
It was done.

Needle punching can be performed using a needle punching machine used for felting a non-woven fabric. The needle punching machine is a device capable of repeatedly driving a needle board, in which a large number of metal needles having hooks are provided at the tip or in the middle of the longitudinal direction, to project vertically to a workpiece and then pulling out the needle board. . Further, the needle punching machine is provided with a moving means such as a belt conveyer capable of horizontally moving the workpiece in synchronization with the driving of the needle board.

According to such a needle punching machine,
When cloth-like materials (eg, non-woven fabrics) and cotton-like materials made of glass fibers are stacked on the surface of the base material and the needle board is driven from the glass fiber side, the glass fibers engaged with the hook portion of the metal needles become metal needles. At the same time, it is driven in the thickness direction of the base material. Furthermore, while moving the substrate horizontally with a belt conveyor,
By driving the needle board, it becomes possible to drive the glass fibers at a uniform interval over the entire base material.

When the needle board is continuously driven in the above-mentioned needle punch, the glass fiber on the surface of the base material is driven into the base material and gradually decreases, and the glass fiber is formed both inside the base material and on the surface of the base material. A high resistance layer is formed. When the driving is further continued, finally, a part of the carbon fiber or the like which constitutes the base material is exposed on the surface.

In the current collector having the high resistance layer thus formed, one surface of the base material is covered with the high resistance layer, and the electric resistance of the portion is high, so that the solid electrolyte tube and the current collector are not charged during charging. It is possible to prevent the formation of an insulating layer by depositing sulfur as an insulator only in the vicinity of the contact surface. Therefore, it is preferable in that the internal resistance of the battery does not increase with the progress of the charging reaction and the charge recovery property is high.

Further, since the glass fiber is punched by the needle punch to form the high resistance layer, the glass fiber is oriented in the thickness direction of the base material. When glass fibers having excellent wettability with respect to sodium polysulfide are oriented in the thickness direction of the base material, the sodium polysulfide moves along the glass fibers, so that the movement of the sodium polysulfide in the current collector is promoted. . Therefore, even when the battery becomes large and the thickness of the current collector increases, there is an effect that smooth charging is possible and the charge recovery rate is increased.

In one embodiment of the current collector of the present invention, in addition to the basic structure described above, one surface of the substrate is further coated.
The high resistance layer provided has a specific configuration which will be described in detail below.
Of. That is, first, the high resistance layer is
The 20% to 85% of the surface is that in which overturned be.
When the surface of the base material is covered with the high resistance layer, the contact area between the carbon fiber or the graphite fiber forming the base material and the outer peripheral surface of the solid electrolyte tube is substantially reduced, so that the internal resistance of the battery is increased. Therefore, by precisely controlling the coverage of the high resistance layer on the surface of the base material (hereinafter referred to as "surface coverage"), it becomes possible to balance the charge recovery property and the internal resistance of the battery in a high dimension. .

Specifically, by setting the surface coverage to 20% or more, the conductivity in the vicinity of the contact surface between the solid electrolyte tube and the current collector can be reliably reduced, and the charge recovery property is improved. It is possible. On the other hand, the surface coverage is 85
When the content is not more than%, the internal resistance of the battery is suppressed to a certain value or less, so that sodium ions can be smoothly moved to the positive electrode side during discharging. When the surface coverage is in the range of 30 to 75%, it is preferable in that the charge recovery property and the internal resistance of the battery can be balanced in a higher dimension.

The surface coverage can be controlled by the number of needle punches when the glass fiber is driven into the substrate. That is, the smaller the number of needle punches, the higher the surface coverage because the glass fibers remain on the surface of the base material, and as the number of times increases, the glass fibers on the surface of the base material are driven into the base material and the surface coverage decreases. Will be done.

The “surface coverage” is defined as a current collector in which glass fibers are punched into a base material with a needle punch, and only needle punching is performed under the same punching conditions (that is, glass fibers are not punched into holes). Cut out the base material in the same area (opened only), measure the resistance value by crimping flat plate electrodes from both front and back sides, and convert from the ratio of the resistance value of the collector to the resistance value of the base material. Is possible.

Secondly, the mass of the glass fiber forming the high resistance layer, which is driven into the inside of the substrate , with respect to the total mass of the substrate.
Proportion of with the scope of 2 to 15 mass% (hereinafter, the mass ratio of "internal mass ratio".). When the glass fiber injected into the base material is 2% by mass or more , the long-term durability of the battery is improved .

As the battery is continuously used, iron, chromium, etc., which are components of the anticorrosion layer on the inner surface of the positive electrode container, become positive electrode active materials .
Reacts with sulfur to form a high electrical resistance sulfide. When the sulfide moves along with sodium polysulfide and is deposited on the solid electrolyte tube, the internal resistance of the battery is increased,
As a result, the charge recovery property is reduced. The glass fiber content of the inner substrate is migration of these sulfides is inhibited and more, the charge recovery over time is maintained, prolonged durability Ru is estimated to increase. On the other hand, in the current collector in which the glass fiber exceeds 15% by mass, the base material is damaged due to the severe needle punching conditions, and the conductivity required for the current collector cannot be secured .

The internal mass ratio can be controlled by the number of needle punches when driving the glass fiber into the substrate. That is, the smaller the number of needle punches, the larger the amount of glass fibers remaining on the surface of the base material, so the internal mass ratio is low, and as the number of times increases, the glass fibers on the surface of the base material are driven into the base material. The mass ratio will increase.

The “internal mass ratio” means that the glass fiber remaining on the surface of the base material of the current collector is cut off by means of a grinder or the like, and then heat-treated in an aerobic atmosphere to burn off the base material portion. Then, it is possible to calculate from the ratio between the actual measurement value of the mass of the remaining glass fiber and the mass of the base material.

[0030] Third, the glass fibers forming the high resistance layer is one that has been driven up to 70% to 100% of the depth of the base thickness. As described above, the glass fiber forming the high resistance layer has the effect of promoting the movement of sodium polysulfide in the current collector, but the deeper the glass fiber is driven in the thickness direction of the base material, the more effective it is. There higher due.

Specifically, by setting the ratio of the depth into which the glass fiber is driven to the thickness of the base material (hereinafter referred to as “internal arrival rate”) to 70% or more, the movement of sodium polysulfide is further promoted. Therefore, the charge recovery property is improved. on the other hand,
If the glass fiber is configured to protrude to the other surface of the base material, it is not preferable in that the contact resistance at the contact surface between the positive electrode container and the current collector becomes high. Therefore, the internal arrival rate must be 100% or less. There is.

[0032]

The internal reach can be controlled by the driving depth of the position of the metal needle hook when driving the glass fiber into the base material. That is, the shallower the driving depth at the metal needle hook position with respect to the base material, the smaller the internal arrival rate, and the closer the driving depth to the thickness of the base material, the larger the internal penetration rate.

The “internal arrival rate” is the measured value of the length of the remaining glass fiber after the heat treatment of the current collector in an oxygen-containing atmosphere to burn off the base material portion and the thickness of the base material before burning. It is possible to calculate from the ratio.

[0035]

Another aspect of the present invention is the NAS battery.
In one embodiment of the pond, a solid electrolyte tube 13 having a cylindrical shape with a bottom is provided inside a positive electrode container 9 having a hollow cylindrical shape as shown in FIG.
Is disposed, together with sodium 2 <br/> as the negative electrode active material in the interior of the solid electrolyte tube 13 is accommodated, the solid electrolyte tube 1
3 sulfur 4 as an external positive electrode active material, a positive electrode container 9
Contact both the inner peripheral surface and the outer peripheral surface of the solid electrolyte tube 13.
The negative electrode current collector 11 arranged as
It is stored separately from sodium 2, which is an active material.
In the NAS battery 1 as described above, as the positive electrode current collector 11,
Positive Electrode Current Collector for Sodium-Sulfur Battery of the Above Embodiment
Use and by arranging that the table surface of one made is coated with a high-resistance layer of the substrate in contact with the outer peripheral surface of the solid electrolyte tube 13
I am With this configuration, it is possible to configure a NAS battery having excellent charge recovery, low internal resistance, and long-term durability.

[0037]

EXAMPLES Hereinafter, the positive electrode current collector for a sodium-sulfur battery of the present invention and the NAS battery using the same will be described in more detail with reference to examples. However, the present invention is not limited to these examples. In addition, in this example
And the basis weight is a sheet-like material (felt material, cloth-like material,
Meaning the mass (g / m ²⁾ of per unit area of the flocculent and the like)
It is tasting and can be calculated by dividing the total mass of the sheet-shaped material by its area.

1. Current collector base material: The base material is made of carbon fiber having a diameter of several μm to several tens of μm, and has a width of 50 cm, a length of 300 cm, and a thickness of 15.
A felt material having a weight of 1 mm and a basis weight of 1700 g / m ² was used. The thickness of the substrate is a plate diameter of 30 mm and a load of 200.
An average value of thicknesses measured at several points in the width direction and the length direction of the substrate was used by using a dial type thickness gauge of g.

High resistance layer: As a material of the high resistance layer,
A non-woven fabric made of glass fiber having a diameter of 10 μm was cut into the same width and length as the base material. The basis weight was appropriately selected and used within the range of 60 to 420 g / m ² .

The high resistance layer was formed by using a needle punching machine, stacking the above-mentioned non-woven fabric on a substrate, and performing needle punching from the non-woven fabric side. By appropriately changing the needle punching conditions such as the needle board needle density, metal needle hook position, punching speed, and substrate feeding speed, various current collectors with different surface coverage, internal reach, and internal mass ratio can be obtained. It was made.

2. Evaluation Method of Current Collector With respect to the current collector prepared as described above, the surface coverage, the internal arrival rate, and the internal abundance rate were evaluated by the following methods.

Surface coverage: First, a current collector (sample A) in which glass fiber was punched into the base material with a needle punch and a base material (sample B) in which only needle punching was performed under the same punching conditions were 350 mm in length. It was cut into a size of 100 mm in width. Next, each sample is 400 mm in length from the front and back sides.
The resistance value was measured by a four-terminal method in a state of being compressed to a thickness of 13 mm with a flat electrode having a width of 200 mm and the surface coverage was calculated from the resistance value Ra of the sample A and the resistance value Rb of the sample B by the following formula (1). Was calculated. Surface coverage [%] = 100 × (1−Rb / Ra) (1)

Internal reach rate: First, a current collector in which glass fiber is driven into a base material by needle punching is 350 mm long ×
A sample was prepared by cutting into a size of 100 mm in width. By subjecting the sample to heat treatment under the conditions of an oxygen atmosphere at 1000 ° C. for 2 hours to burn off the base material portion, from the measured value Lr of the length of the remaining glass fiber and the base material thickness Li before the heat treatment, The internal arrival rate was calculated according to (2). Internal arrival rate [%] = 100 × Lr / Li (2)

Internal mass ratio: First, a current collector in which glass fiber is driven into a base material by needle punching is 350 mm long ×
A piece was cut into a size of 100 mm in width, and only the glass fiber remaining on the surface of the base material (that is, the portion not driven into the base material) was cut out by a means such as a grinder to prepare a sample. Then, the sample is placed in an aerobic atmosphere at 100
The base material portion was burnt down by heat treatment at 0 ° C. for 2 hours, and the internal mass ratio was calculated by the following formula (3) from the measured value Wa of the residual glass fiber mass and the mass Wb of the base material. Internal mass ratio [%] = 100 × Wa / Wb (3)

3. Evaluation Method of Battery Characteristics A NAS battery 1 having the structure shown in FIG. 1 was constructed by incorporating the above-described current collector, and the correlation between the current collector characteristics and the battery performance was investigated. The positive electrode container 9 has an outer diameter of 92 mm, and the solid electrolyte tube 13 has a total length of 450 mm, an outer diameter of 60 mm, and a wall thickness of 2.5 mm.
The current collector 11 has a thickness of 14 mm and a length of 350 mm.
I used the one. The battery performance was evaluated by the following method. The results are shown in Table 1 .

Internal resistance: After attaching current and voltage terminals to the positive electrode and the negative electrode of the battery, the battery was placed in a high temperature bath at 320 ° C. and charged and discharged at the rated current. In each state of discharging and charging, the resistance value is converted from the battery voltage and the energizing current during charging / discharging, and the average resistance over the entire discharging and charging regions is calculated.
The average discharge resistance and the average charge resistance were calculated. The average resistance value was calculated from the arithmetic average of these average discharge resistance and average charge resistance. When the average resistance value is less than 3.5 mΩ, ◎, 3.5
When mΩ or more, it was evaluated as x.

Charge recovery rate: From the uncharged capacity Cr (Ah) and the designed capacity Cf (Ah) of the battery when the termination condition at the time of charging the battery is a constant voltage, the charge recovery rate is calculated by the following formula (4). I calculated. The determination method is as follows: the value at the rated charging current of the battery is the charge recovery rate 1, the value at the rated 1/4 charging current is the charge recovery rate 2, and the charge recovery rate 1 is 90% or more, and the charge recovery rate is 90% or more. When the rate 2 was 95% or more, it was evaluated as ⊚, and when the charge recovery rate 1 was less than 90%, or when the charge recovery rate 2 was less than 95%, it was evaluated as x. Charge recovery rate [%] = 100 × (1-Cr / Cf) (4)

Long-term durability Long-term durability was evaluated by the rate of increase in average resistance, and
17mΩ / ◎ for less than 180 days, 0.17mΩ
/ 180 days or more was evaluated as x.

[0049]

[Table 1]

[0050] As shown in Table 1, 20 is the front surface coverage
NAS batteries using 85% current collector showed good internal resistance. On the other hand, the surface coverage is less than 20% ( Comparative Examples 1 to 1
8) or a NAS battery using more than 85% ( Comparative Examples 9 to 13 ) of the current collector had a high internal resistance.

[0051]

As shown in Table 1 , all the NAS batteries using the current collector having the internal reach of 70 to 100% showed a good charge recovery rate. Above all, the surface coverage is 20 to 8
Those in the range of 5% had a low internal resistance of the battery and showed favorable results. On the other hand, the NAS battery using the current collector having the internal arrival rate of less than 70% ( Comparative Examples 17 and 20 ) had a low charge recovery rate. Further, the NAS batteries using a collector of more than 100% ( Comparative Examples 18 and 19 ) had a good charge recovery rate, but the internal resistance of the battery was high.

[0053]

[0054] Further, as shown in Table 1, field but inside the mass ratio showed good long-term durability for NAS batteries using a current collector of 2 to 15 wt%, less than 2 wt%
If (Comparative Example 14 to 16), and needle punching conditions over
When it was severe and exceeded 15% by mass (Comparative Examples 17 and 18 ), long-term durability was poor . Thus, one side of the substrate
The high resistance layer coated on the surface has a specific configuration (surface
Meets all requirements for coverage, internal mass ratio, and internal reach
In some cases, it may be possible to achieve the object of the present invention.
Recognize.

[0055]

As described above, the sodium of the present invention is used.
Positive electrode current collector for lithium-sulfur batteries
When used, it has excellent charge recovery and long-term durability.
And to provide a sodium-sulfur battery with low internal resistance.
And the effect of being able to
The sodium-sulfur battery using this has a charge recovery property and
It has excellent long-term durability and low internal resistance.
Demonstrate . Such a NAS battery is particularly useful when the thickness of the positive electrode current collector for a sodium-sulfur battery increases as the battery becomes larger.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a general embodiment of a sodium-sulfur battery.

[Explanation of symbols]

1 ... NAS battery, 2 ... Sodium, 3 ... Insulator ring,
4 ... Sulfur, 5 ... Cylindrical metal fitting, 7 ... Cathode metal fitting, 9 ... Positive electrode container, 10 ... Constriction part, 11 ... Positive electrode collector, 13 ... Solid electrolyte tube.

─────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-8-130032 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01M 10/39 H01M 4/64-4 / 84

Claims (2)

(57) [Claims] 1. A state in which sulfur as a positive electrode active material is impregnated.
The inner peripheral surface of the positive electrode container of the sodium-sulfur battery and the solid
It is arranged so as to contact both the outer peripheral surface of the electrolyte tube and
The felt-like base material made of carbon fiber or graphite fiber used and one surface of the base material should be coated.
That the interior of the base glass fiber by needle punching
Sodium with a high resistance layer which is out write or are in formed
Beam - a sulfur battery positive electrode current collector, to the total mass of the base material, the mass of the glass fibers constituting the high resistance layer implanted into the interior of the substrate split
If it is in the range of 2 to 15 wt%, the high-resistance layer
Before Symbol glass fibers constituting the, inside of the substrate, contact is driven to 70% to 100% of the depth of thickness of the base
20% to 85% of one surface of the base material is
Natriu characterized by being covered with a resistance layer
Positive electrode current collector for Mu-Sulfur battery . Wherein inside the bottomed cylindrical solid electrolyte tube of hollow cylindrical positive electrode container is disposed, with sodium as a negative electrode active material in the interior of the solid electrolyte are housed,
Sulfur as an external positive electrode active material of the solid electrolyte, before
The inner peripheral surface of the positive electrode container and the outer peripheral surface of the solid electrolyte tube are combined with each other.
Impregnated into the positive electrode current collector arranged so as to abut one side
In this state, it is isolated from sodium as the negative electrode active material.
Is sodium becomes housed by - a sulfur battery, as the positive electrode current collector, sodium of claim 1 -
Cathode current collector for sulfur batteries, the high resistance layer of the base material
Sodium front surface of one comprising coated is characterized by being used is disposed so as to contact the outer peripheral surface of the solid electrolyte tube Ri - sulfur battery.