JPH0594825A - Inorganic nonaqueous electrolyt battery - Google Patents

Abstract

(57) [Summary] [Purpose] In a sulfuryl chloride-controlled inorganic non-aqueous electrolyte battery in which sulfuryl chloride also serves as a positive electrode active material and a solvent for the electrolyte, a second-stage discharge is generated before the end of the battery life. The end of discharge can be detected so that the battery can be replaced at an appropriate time. [Structure] In a non-aqueous electrolyte battery of sulfuryl chloride regulation in which sulfuryl chloride also serves as a solution of the positive electrode active material and the electrolytic solution, a thionyl chloride is contained in the electrolytic solution, and a second stage based on thionyl chloride Generate a discharge.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sulfuryl chloride-regulated inorganic nonaqueous electrolyte battery using an alkali metal or alkaline earth metal as a negative electrode active material and sulfuryl chloride as a positive electrode active material and a solvent for an electrolytic solution.

[0002]

2. Description of the Related Art An inorganic non-aqueous electrolyte battery using an alkali metal or an alkaline earth metal as a negative electrode active material and sulfuryl chloride as a positive electrode active material and a solvent for an electrolytic solution has a high energy density and operates at a low temperature. It has excellent characteristics.

[0003]

However, in the above inorganic non-aqueous electrolyte battery, since the discharge proceeds in a non-uniform reaction and the internal resistance does not change until the end of discharge, the open circuit voltage and the operating voltage of the battery are reduced. Flatness is maintained until the end of discharge.

As a result, the active material on the side that regulates the discharge capacity disappears, and at the same time, the battery voltage drops sharply and the life of the battery ends. Therefore, in such an inorganic non-aqueous electrolyte battery, there is a problem that it is not possible to know the end of discharge before the end of the battery life, and as a result, it is difficult to replace the battery at an appropriate time.

Therefore, the present invention solves the problems of the above-mentioned conventional inorganic non-aqueous electrolyte battery and provides an inorganic non-aqueous electrolyte battery capable of detecting the end of discharge before the end of the battery life. With the goal.

[0006]

According to the present invention, in a sulfuryl chloride-controlled inorganic non-aqueous electrolyte battery using sulfuryl chloride as an electrolyte solvent, the life of the battery is terminated by adding thionyl chloride to the electrolyte. It is designed to detect the end of discharge before.

That is, since thionyl chloride is discharged at a potential lower than that of sulfuryl chloride, thionyl chloride does not cause a discharge reaction while sulfuryl chloride is present, and only the discharge reaction of sulfuryl chloride proceeds.

However, when sulfuryl chloride disappears, thionyl chloride reacts with the alkali metal or alkaline earth metal of the negative electrode active material and discharges at a voltage different from that of sulfuryl chloride, resulting in a so-called two-stage discharge.

Therefore, the end of discharge can be detected before the end of the battery life due to the voltage change, and as a result, the battery can be replaced at an appropriate time.

The amount of thionyl chloride in the electrolytic solution is suitably 2 to 40% by weight of thionyl chloride in the electrolytic solution.

When the amount of thionyl chloride in the electrolytic solution is less than 2% by weight, the discharge voltage of thionyl chloride does not sufficiently appear,
Therefore, it is difficult to detect the two-stage discharge, and when thionyl chloride in the electrolytic solution exceeds 40% by weight, the sulfuryl chloride decreases correspondingly, and the portion discharged at the potential of the sulfuryl chloride decreases and the original The characteristics of the high-voltage discharge battery will be lost.

In the present invention, the amount of discharge electricity of the battery is regulated by sulfuryl chloride because the discharge reaction between thionyl chloride and the negative electrode active material occurs if the negative electrode active material does not exist after the discharge of sulfuryl chloride. This is because the end of discharge cannot be detected.

In the present invention, examples of the alkali metal as the negative electrode active material include lithium, sodium and potassium, and examples of the alkaline earth metal include magnesium and calcium.

In the battery of the present invention, a carbon porous molded body containing carbon as a main constituent material is used for the positive electrode.

The electrolytic solution is sulfuryl chloride and LiAlCl.
₄ , LiAlBr ₄ , LiGaCl ₄ , LiB ₁₀ Cl ₁₀
It is prepared by dissolving an electrolyte such as.

Thionyl chloride may be added to the electrolytic solution prepared as described above, or may be added to sulfuryl chloride during the preparation of the electrolytic solution, and LiAlCl ₄ may be added to the mixed solution.
It may be prepared as an electrolytic solution containing thionyl chloride by dissolving an electrolyte such as.

[0017]

EXAMPLES Next, the present invention will be described more specifically with reference to examples.

Example 1 Lithium chloride was used as the negative electrode, and LiAlC was used as an electrolytic solution in a mixed solution of sulfuryl chloride and thionyl chloride in a weight ratio of 4: 1.
The l ₄ with those obtained by dissolving 1.2 mol / l, sulfuryl chloride - was produced AA inorganic non-aqueous electrolyte battery having the structure shown in FIG. 1 with a lithium-based.

The battery shown in FIG. 1 will be described. Reference numeral 1 is a negative electrode, and the negative electrode 1 is formed into a cylindrical shape by pressing a lithium sheet onto the inner peripheral surface of a cylindrical battery case 2 made of stainless steel and having a bottom. Has been done.

Reference numeral 3 is a positive electrode, and this positive electrode 3 is composed of a cylindrical carbon porous molded body whose main constituent material is carbon which is obtained by adding a small amount of graphite and polytetrafluoroethylene as a binder to acetylene black. The negative electrode 1 is installed via the separator 4. The separator 4 is made of a non-woven glass fiber and has a cylindrical shape.

Reference numeral 5 is an electrolytic solution. This electrolytic solution 5 uses sulfuryl chloride, which is a positive electrode active material, as an electrolytic solution solvent and also contains thionyl chloride.

In this battery, since sulfuryl chloride of the positive electrode active material also serves as the electrolytic solution solvent as described above, a large amount of electrolytic solution 5 is injected into the battery, unlike other batteries. As can be seen from the fact that sulfuryl chloride is the positive electrode active material, the positive electrode 3 does not react by itself, but sulfuryl chloride of the positive electrode active material and the negative electrode 1
It provides a place for reaction with the lithium ions that have been ionized and eluted from.

Reference numeral 6 is a positive electrode current collector made of a stainless steel rod, 7 is a battery lid, and this battery lid 7 has a body 8, a glass layer 9 and a positive electrode terminal 10, and the body 8 is made of stainless steel. The raised outer peripheral portion is joined to the open end of the battery case 2 by welding.

The glass layer 9 is provided on the inner peripheral side of the body 8. The glass layer 9 insulates the body 8 and the positive electrode terminal 10 from each other, and the constituent glass is formed on the outer peripheral surface of the body 8.
Of the constituent glass is fused to the outer peripheral surface of the positive electrode terminal 10 to seal between the body 8 and the positive electrode terminal 10.

The positive electrode terminal 10 is made of stainless steel, and a part of the positive electrode terminal 10 has a pipe shape during battery assembly and is used as an electrolyte injection port. The positive electrode terminal 10 is inserted into the hollow part after the electrolyte is injected. It is welded to the upper portion of the current collector 6 and sealed.

Reference numeral 11 denotes a bottom insulating material. This bottom insulating material 11 is made of glass fiber non-woven fabric and insulates the positive electrode 3 from the battery case 2 which also serves as a negative electrode terminal.

Reference numeral 12 denotes an upper insulating material. This upper insulating material 12 is made of the same glass fiber non-woven fabric as the bottom insulating material 11, and has a body 8 of the battery lid 7 which also serves as the positive electrode 3 and the negative electrode terminal.
Is insulated from.

The battery was assembled as follows. First, a lithium sheet was pressure-bonded to the inner peripheral surface of a bottomed cylindrical battery case 2 to form a negative electrode 1, and the separator 4 was arranged in a cylindrical shape along the inner peripheral surface of the negative electrode 1.

Next, the bottom insulating material 11 is placed on the bottom of the battery case 2, and the cylindrical positive electrode 3 is provided on the inner peripheral side of the separator 4.
Is inserted, the upper insulating material 12 is placed on the positive electrode 3, the battery lid 7 is fitted into the opening of the battery case 2, and the outer peripheral portion of the body 8 of the battery lid 7 and the open end of the battery case 2 are connected. Welded and joined with carbon dioxide laser.

Next, from the pipe portion of the battery lid 7 to the electrolytic solution 5
Is injected into the battery, the positive electrode current collector 6 is inserted into the pipe portion after the electrolyte solution 5 is injected, and the lower end of the positive electrode current collector 6 is passed through the upper insulating material 12 to reach the positive electrode 3. Current collector 6
The upper portion of the above was welded to the upper end of the pipe portion to be hermetically sealed, the positive electrode terminal 10 was configured, and the battery was assembled in the state shown in FIG.

In this battery, the amount of lithium is 490 m
g, and the theoretical amount of electricity is 1890 mAh. The amount of carbon of the positive electrode was 750 mg, the amount of sulfuryl chloride in the electrolytic solution was 4240 mg, the theoretical amount of electricity of this sulfuryl chloride was 1685 mAh, and this battery is regulated by sulfuryl chloride. In addition, thionyl chloride is 1060m
and the theoretical electric quantity of thionyl chloride is 480 m.
It is Ah.

Comparative Example 1 As an electrolytic solution, sulfuryl chloride and LiAlCl ₄ of 1.
An AA-type inorganic non-aqueous electrolyte battery of a sulfuryl chloride-lithium system was prepared in the same manner as in Example 1 except that the solution of 2 mol / l was used.

FIG. 2 shows the discharge characteristics when the battery of Example 1 and the battery of Comparative Example 1 were continuously discharged at 20 ° C. under a load of 10 kΩ.

As shown in FIG. 2, the battery of Example 1 had a battery of 3.
Following the flat discharge voltage around 8V, a second-stage discharge is observed around 3.55V.

The above-mentioned flat discharge near 3.8 V is based on sulfuryl chloride, and the second discharge near 3.55 V is based on thionyl chloride. The two-stage discharge allows the end of discharge to be detected before the end of the battery life, and the battery can be replaced at an appropriate time.

On the other hand, the battery of Comparative Example 1 has 3.8V.
After a flat discharge in the vicinity, the discharge voltage drops sharply, ending the life of the battery. Therefore, in the battery of Comparative Example 1,
Since the end of discharge cannot be detected before the end of its life, it is difficult to replace the battery at an appropriate time.

[0037]

As described above, according to the present invention, in a sulfuryl chloride-controlled inorganic non-aqueous electrolyte battery using sulfuryl chloride as a solvent for a positive electrode active material and an electrolytic solution, thionyl chloride is contained in the electrolytic solution. As a result, the second stage discharge based on thionyl chloride can be generated before the end of the battery life, and the end of discharge can be detected.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of an inorganic non-aqueous electrolyte battery according to the present invention.

FIG. 2 is a diagram showing discharge characteristics of the battery of Example 1 of the present invention and the battery of Comparative Example 1.

[Explanation of symbols]

 1 Negative electrode 3 Positive electrode 4 Separator 5 Electrolyte

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Taku Sasama 1-88, Torora, Ibaraki-shi, Osaka Within Hitachi Maxell Co., Ltd. (72) Kaoru Kutomi 1-88, Torora, Ibaraki, Osaka Hitachi Maxel Co., Ltd.

Claims (2)

[Claims] 1. An inorganic non-aqueous electrolyte battery regulated by sulfuryl chloride, wherein an alkali metal or an alkaline earth metal is used as a negative electrode active material, and sulfuryl chloride is used as a positive electrode active material and a solvent for an electrolytic solution, and thionyl chloride is contained in the electrolytic solution. An inorganic non-aqueous electrolyte battery characterized by being contained. 2. The concentration of thionyl chloride in the electrolytic solution is 2-4.
The inorganic non-aqueous electrolyte battery according to claim 1, which is 0% by weight.