JPS63175347A - Nonaqueous solvent battery - Google Patents

Abstract

PURPOSE:To shorten a voltage recovering time in the beginning of a large current discharging and furthermore prevent a long-time deterioration of a discharge voltage and discharge capacity by adding a vinyl-based polymer having a chlorine substituent and lead compound to an electrolyte. CONSTITUTION:Polyvinyl chloride, polyvinylidene chloride, vinyl chloride- vinylidene chloride copolymer, and ethylenevinyl chloride copolymer etc., for instance, are used for a vinyl-based polymer having a chlorine substituent. An adding quantity to an electrolyte of the vinyl-based polyger is to be 0.2-10 g per 1l of the electrolyte. Organic lead compounds, for instance, basic phthalic acid lead and lead stearate etc., basic lead sulfate, and basic phasphorous acid lead etc. are used for lead compounds. An adding quantity of lead compounds is to be 1-10 wt.% of vinyl-based polymer quantity to be added.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a non-aqueous solvent battery, and more particularly to a non-aqueous solvent battery in which an electrolytic solution that also serves as a positive electrode active material is improved.

(Prior art) Nonaqueous solvent batteries using at least one of the light metals lithium, sodium, aluminum, potassium, and calcium as negative electrode active materials have a high energy density, excellent storage characteristics, and a wide operating temperature range. Calculator 2 watch due to its features.

It is often used as a backup power source for memory.

Among them, lithium is used for the negative electrode, and thionyl chloride (sOcL) and sulfuryl chloride (So□Cβ) are used as the positive electrode active material.
Batteries using sulfur oxyhalides such as 2) are
It has attracted particular attention because of its high energy density. These batteries have a positive electrode consisting of carbon and a metal current collector;
Generally aluminum chloride (AlCI23).

A liquid sulfur oxyhalide obtained by dissolving a Lewis acid such as aluminum bromide (AlBr3) and a Lewis base such as lithium chloride or lithium bromide is used as the electrolyte. Therefore, the liquid oxyhalide serves both as a positive electrode active material and as an electrolyte, and by using a positive electrode with an appropriate shape and shape, a battery with excellent high rate discharge characteristics can be expected.

By the way, in the above-mentioned battery, since the sulfur oxyhalide, which is the positive electrode active material, is in direct contact with the lithium of the negative electrode, LiCff, which is a reactive oxide, is formed on the surface of the negative electrode lithium.
1 film is produced. This Li(Q film) has the function of preventing direct contact between the negative electrode lithium and the oxyhalide, and plays a role in preventing battery capacity deterioration during storage.However, during discharging, it acts as a resistance component, The degree of this voltage drop is small and can be ignored when the discharge current is minute on the order of μA, but it cannot be ignored when the discharge current is large, especially when stored at high temperatures for long periods of time. After considerable film growth has occurred,
When discharging at low temperatures, a large voltage drop occurs at the start of discharge, and it takes a considerable amount of time to recover to a predetermined voltage, which is a problem known as the so-called voltage delay phenomenon.

For this reason, several proposals have been made to solve the above problems, such as Japanese Patent Application Laid-Open No. 56-7360.
The publication discloses dissolving vinyl polymers such as vinyl chloride, homopolymers of vinylidene chloride, and copolymers of vinyl chloride and vinyl acetate during electrolysis.

(Problems to be Solved by the Invention) Although it is true that the voltage delay phenomenon is improved by dissolving a vinyl polymer having a chlorine substituent in an electrolytic solution, an electrolytic solution in which only a vinyl polymer is dissolved When a battery is used, the effect of adding the vinyl polymer weakens when the battery is stored for a long period of time, resulting in a problem that the voltage drop at the start of discharge becomes large and the time required to recover to a predetermined voltage becomes long.

The purpose of the present invention is to solve the above-mentioned problems, and to provide a non-aqueous solvent battery that has a small voltage drop even in the early stages of large current discharge, has a short voltage recovery time, and does not deteriorate even after long-term storage of the battery. It is about providing.

[Structure of the invention]

(Means and effects for solving the problems) The non-aqueous solvent battery of the present invention uses lithium and sodium.

A non-aqueous solvent consisting of a negative electrode made of at least one of light metals such as aluminum, potassium, and calcium, a positive electrode mainly made of carbon, and an electrolytic solution that also serves as a positive electrode active material and mainly made of sulfur oxyhalide. The battery is characterized in that a vinyl polymer having a chlorine substituent and a lead compound are added to the electrolyte.

The vinyl polymer having a chlorine substituent in the present invention is
Mainly refers to single polymers, copolymers, and mixtures of polymers having a structure represented by the following general formula.

Examples include polyvinyl chloride, polyvinylidene chloride, vinyl chloride-vinylidene chloride copolymer, ethylene-vinylidene chloride,
These include vinyl chloride copolymer, vinyl chloride-vinyl acetate copolymer, and the like.

The amount of these vinyl polymers added to the electrolyte is as follows:
0.2-1 (19 i.e. 0.2-1
0%/fi +71 range, special 0.3~59. l)
This is because if the amount of vinyl polymer added is less than 0.2910, the effect of suppressing voltage drop etc. cannot be sufficiently exhibited;
This is because if it exceeds /a, not only will the effect hardly increase, but the discharge capacity of the battery may even decrease.

In addition, the lead compounds in the present invention include basic lead phthalate,
Organic lead compounds such as lead stearate, basic lead sulfate, basic lead sulfite, and basic lead sulfite.

Any inorganic lead compound such as lead dioxide or lead chloride may be used.

The amount of these lead compounds added may be 1 to 10% + 1% of the amount of vinyl polymer added to the electrolyte.If the amount of lead compounds added is less than 1 wt%, the voltage drop suppression effect will be reduced. It does not last for a long period of time, and on the other hand, even if it exceeds 10 vt%, the long-term sustainability of the effect will hardly improve, and there is a risk that the battery performance will deteriorate on the contrary.

In the non-aqueous solvent battery according to the present invention, by further adding a lead compound to a predetermined amount of the vinyl polymer, the effect of improving the voltage delay phenomenon can be maintained for a long period of time. The reason for this is not clear in detail, but it is thought that the above effect is produced by a small amount of lead compound and vinyl polymer acting synergistically in the electrolyte.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

Example FIG. 1 shows a sectional view showing the structure of a non-aqueous solvent battery in this example and a comparative example.

Reference numeral 1 in the figure is a bottomed cylindrical can made of stainless steel, for example, with an open top that also serves as a negative electrode terminal.

A cylindrical negative electrode 2 made of metallic lithium is pressure-bonded to the inner surface of the can 1. Inside the can 1 inside the negative electrode 2, a positive electrode having a structure in which a cylindrical porous carbon layer 4 is crimped onto the outside of a metal current collector 3 made of a cylindrical stainless steel net is provided with a separator 61 made of a glass nonwoven fabric. 62. The positive electrode 5 is made by mixing commercially available acetylene black and polytetrafluoroethylene, and molding the mixture together with a stainless steel mesh metal current collector 3 into a cylindrical shape so that the current collector is on the inside. The porous carbon layer 4 is produced by forming the hybrid material into a porous carbon layer 4 by drying it under vacuum at 150°C.

Further, in the can body 1 above the positive electrode giant, an insulating paper 7 having a hole in the center and supported by the separator 6 □ is disposed. A metal top 8 is sealed to the upper opening of the can body 1 by laser welding or the like, and a pipe-shaped positive electrode terminal 10 is connected to a hole 9 in the center of the metal top 8 through a sealing material 11 made of glass. The metal top 8 is electrically insulated and fixed to the metal top 8. The lower end of the positive electrode terminal 10 is connected to the metal current collector 3 of the positive electrode via a lead wire 12. The can body 1 accommodates an electrolytic solution 13 injected from the pipe-shaped positive electrode terminal 10.

Furthermore, an enclosure 14 made of stainless steel, for example, is inserted into the pipe-shaped positive terminal 10, and the tip of the terminal 10 and the inserted enclosure 14 are laser welded to
is sealed.

As an example, 5vt% of aluminum chloride (CAQcQs) and lithium chloride (LiCj) were dissolved in thionyl chloride (SOCg) at 1.5 mol/Ω each.
Ninety batteries were fabricated using an electrolyte in which polyvinyl chloride added with basic lead sulfate (3PbO.pbso, 2S)/Q was added and dissolved.

Comparative example l AnICI in 5OCQ□! , and LiCQ each at 1.
Basic lead sulfate (3Pb
2.0% polyvinyl chloride without adding O-PbSO4)
9/j! Batteries (90 batteries) having the same structure as in Example except that an electrolyte solution added and dissolved at a concentration of

Comparative Example 2 SOCQ, 1cffi, Li(4) and 1.5% each
Basic lead sulfate (3Pb
A battery (9
0 pieces) were assembled.

However, this example and comparative example 1.・Storage the batteries at 20°C after assembly, after 6 months, 12 months, and 24
After several months, 30 pieces of each were taken out and subjected to a constant resistance discharge of 30Ω, and the time taken for the voltage to return to 2.5V after the start of discharge, the average operating voltage, and the discharge capacity were measured.

The results are shown in Table 1.

Table 1 (values are average values of 30 samples) As is clear from Table 1, basic lead sulfate (3
The battery of the example in which both PbO/pbso4) and polyvinyl chloride were added was basic lead sulfate (3PbO-PbSO4) and polyvinyl chloride.
It can be seen that the voltage recovery time at the start of discharge is shorter than that of the battery of Comparative Example 1 in which only polyvinyl chloride was added without adding polyvinyl chloride. This difference in voltage recovery time becomes more pronounced as the storage period becomes longer.Also, the battery of the example is even better than the battery of comparative example 2 in which only basic lead sulfate (3PbO・pbso4) is added. It can be seen that the voltage recovery time at the start of discharge is extremely short.

Furthermore, the battery of Example is Comparative Example 1. Compared to the battery of Comparative Example 2, even if a large current is discharged after storage, there is no significant voltage drop at the start of discharge, the average operating voltage and discharge capacity are large, and there is almost no deterioration due to long-term storage.

In addition to the above-mentioned effects, the battery of the present invention has excellent discharge characteristics at low temperatures and suffers little capacity deterioration due to long-term storage at low temperatures.

〔Effect of the invention〕

As detailed above, according to the present invention, the voltage recovery time at the initial stage of large current discharge is short, long-term deterioration of discharge voltage and discharge capacity is also suppressed, and the non-aqueous solvent has excellent discharge characteristics after long-term storage. You can get batteries.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of the structure of a nonaqueous solvent battery. 1...Can body, 2...Negative electrode, 3...
Metal current collector, 4... Porous carbon layer, l... Positive electrode, 6□, 6. ...Separator. 8...Metal top, 10...Pipe-shaped positive electrode terminal, 13...Electrolyte solution. Agent Patent Attorney Nori Chika Yudo Kikuo Takehana

Claims (1)

[Claims] (1) A negative electrode made of at least one of light metals such as lithium, sodium, aluminum, potassium, and calcium, a positive electrode mainly composed of carbon, and an electrolytic solution that also serves as a positive electrode active material and mainly composed of sulfur oxyhalide. A non-aqueous solvent battery comprising: a vinyl polymer having a chlorine substituent and a lead compound added to the electrolytic solution.