JPS5987773A - organic electrolyte battery - Google Patents

Abstract

PURPOSE:To improve the high temperature characteristic of an organic solvent battery, which has a positive electrode and a negative electrode which is made by using a light metal as an active material, by using a mixture solvent consisting of propylene carbonate and diethylene glycol dimethyl ether in preparing electrolyte. CONSTITUTION:A positive electrode is made by sintering a positive pellent formed by pressing and molding a positive mixture prepared by mixing an active material consisting of thermally treated manganese dioxide, acetylene black and graphite used as conductive agents and fluorine resin powder used as a binding agent. A negative electrode is made by punching a rolled lithium plate. A nonwoven polypropylene fabric is used as a separator. Electrolyte is prepared by dissolving lithium perchlorate in a mixture solvent consisting of propylene carbonate and diethylene glycol dimethyl ether. By the means mentioned above, a battery having an excellent discharge characteristic at high temperature is obtained.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention provides a negative electrode using a light metal such as lithium, sodium, or magnesium as an active material, and a positive electrode using a metal oxide, sulfide, or halide as an active material. The present invention relates to an organic electrolyte battery comprising an electrolyte in which an inorganic salt solute such as lithium perchlorate or lithium fluoroborate is dissolved in an organic solvent such as propylene carbonate, γ-butyllactone, or dimethoxyethane.

Conventional technology This type of battery has many advantages such as high voltage, high energy density, and little self-discharge.At present, batteries using manganese dioxide or carbon fluoride as the positive electrode active material are in practical use. has been made into In particular, the stability of carbon dioxide,
It can be said to be an excellent positive electrode active material in terms of economic efficiency.

Now, speaking of electrolytes, a mixed solvent of propylene carbonate and dimethoxyethane is generally used as a solvent.The reason for this is that although propylene carbonate has a high dielectric constant, it has a high viscosity. In order to compensate for this, dimethoxyethane, which has a low viscosity, is mixed and used as an auxiliary solvent.

By the way, dimethoxyethane as an auxiliary solvent has a boiling point as low as 85°C at 1 atm, so there is a problem with battery characteristics especially at temperatures above 60°C.Purpose of the Invention In view of the above problems, the present invention has been developed to The organic type 1v? exhibits excellent battery characteristics even in The purpose of the present invention is to provide a quality battery.
Its gist is that it is equipped with a negative electrode made of a light metal as an active material, a positive electrode, and an electrolyte made of a solvent and a solute, the solvent being propylene carbonate (PC) and diethyl glycol dimethyl ether [CHs(OCR2CH2 ) 20cI-
The organic electrolyte battery is characterized in that it is a mixed solvent of 1 s J .

Examples Examples of the present invention will be described in detail below.The positive electrode was made of a carbon dioxide active material heat-treated at 650°C to 430°C in air, acetylene black and graphite as conductive agents,
Fluororesin powder as a binder: 85='10:
A positive electrode mixture mixed at a weight ratio of 5:5 was press-molded at a pressure of about 1 ton/- to form a positive electrode pellet with a diameter of about 15 mm and a thickness of about 1.1 m, and this pellet was made into a 250"C-3 [). The positive electrode is baked at 0°C humidity.

The negative electrode was a lithium rolled plate with a thickness of about 0.6 mm and punched into a diameter of about 1.5 mm, and the separator was made of polypropylene nonwoven fabric.The electrolyte was a mixture of propylene carbonate and diethylene glycol dimethyl ether at a mixing ratio of 1. A battery (A) of the present invention was prepared using a mixture of 1 mol/l of lithium perchlorate dissolved in the mixed solvent prepared in step 1.

A comparative battery (13) was prepared in the same manner as in Example except that 1 mol/l of lithium perchlorate was dissolved in the mixed solvent.

Effects of the invention W Figures 1 to 3 show the invention battery (A) and comparative battery (B).
It is a comparison diagram of battery characteristics at a load of 5.6 KΩ with
Figure 1 shows the initial discharge characteristics at 20°C, Figure 2 shows the discharge characteristics at 30°C after 2 years of storage at 30°C, and Figure 3 shows the discharge characteristics at 60°C.
After storage for several months, the discharge characteristics at 60°C are shown.

As can be seen from these characteristic diagrams, there is almost no difference in the initial N1 discharge characteristics at 20'C, but in the case of discharge at 30'C or higher, the present invention's Denkigai A) is better than the comparison battery. (B
) The decrease in capacity is less than that of

Considering the reason for this, as mentioned above, the boiling point of dimethoxyethane is 850 at 1 atmosphere, whereas the boiling point of diethylene glycol dimethyl needle is 162'C at 1 atmosphere, and at 20C. The vapor pressure of dimethoxyecune is 48 van Ig, while that of diethylene glycol dimethyl ether is 3++
mHg, it is thought that the battery of the present invention will have less deterioration in capacity, especially in terms of discharge and characteristics at high temperatures.

The mixing ratio of propylene carbonate and diethylene glycol dimethyl ether is preferably 1:3 to 3:1. If the amount of propylene carbonate is further increased outside this range, the viscosity will increase, which is not preferable.
Also, if the amount of diethyl glycol dimethyl ether increases further, the proportion of the solvent with a lower boiling point will increase compared to propylene carbonate, which is preferable! ! -No.

[Brief explanation of the drawing]

Are all the figures originally from J-den? Figure 1 shows the initial discharge characteristics at 20°C,
Figure 2 shows the discharge characteristics at 30°C after 2 years of storage at 60'C.
Figure 3 shows the discharge characteristics at 60°C after two months of storage at 60°C. (A)...Battery of the present invention, (B)...Conventional battery. Figure V chant (hr) Figure 2 Figure 8 357

Claims (1)

[Scope of Claims] ■ A negative electrode comprising a light metal as an active material, a positive electrode, and an electrolyte comprising a solvent and a solute, characterized in that the solvent is a mixed solvent of propylene carbonate and diethylene glycol dimethyl ether. Organic electrolyte battery. (2) The organic electrolyte battery according to claim 0, characterized in that the mixing ratio of the mixed solvent is 1:3 to 3:1.