JPS63200464A - organic electrolyte battery - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to improvements in organic electrolyte batteries, particularly flat batteries.

BACKGROUND OF THE INVENTION Since organic electrolyte batteries have high energy density, flat coin-shaped batteries are now required.

In this flat battery, separators are conventionally used as follows.

A negative electrode is crimped onto a sealing plate into which a gasket has been previously inserted, and a punched separator is squeezed into a tap shape along the inner surface of the gasket and fixed within the sealing plate. An electrolytic solution and a positive electrode were inserted into this cup-shaped separator.

Problems to be Solved by the Invention However, in the conventional method, when increasing the internal volume of the sealing plate and increasing the capacity, increasing the depth of the sealing plate causes the shrinkage of the ends of the separator that occurs when the separator is squeezed. As the separator becomes larger and the inner diameter of the separator becomes smaller than the diameter of the positive electrode to be inserted, process troubles due to poor insertion occur frequently when inserting the positive electrode, and internal resistance increases and discharge abnormalities occur due to the separator getting caught. Furthermore, if the punched separator and sealing plate are squeezed with their centers misaligned, the separator will have long and short sides, and the longer part will protrude from the gasket surface, causing the gasket and positive electrode case to overlap during sealing. Since it is caulked and sealed while being sandwiched between the parts, leakage resistance is reduced.

In addition, as batteries become smaller and thinner, the ends of the separator cannot be sufficiently folded into the sealing plate when the separator is squeezed, making it unstable to fix the separator. The parts may come off or become misaligned, causing process problems. In addition, in conventional separators, when the amount of electrolyte decreases, sufficient electrolyte is not secured in the separator portion, resulting in an increase in internal resistance during discharge and a decrease in capacity due to a decrease in reaction efficiency.

The present invention aims to solve the above-mentioned conventional problems, stabilize the process, and improve the discharge characteristics and leakage resistance of the battery.

Means for Solving the Problem In order to solve this problem, the present invention has a ring that holds the separator and has an inverted cross-section, and a separator punched into a disk shape is inserted into this ring. The periphery of the separator is held between the periphery of the upper surface of the positive electrode and the inwardly extending portion of the ring.

Function: By using this ring, it is possible to omit the process of drawing the seven pallets, which causes wrinkles at the edges that occur when drawing the seven pallets, and the long and short sides of the sides that occur due to center deviation. This eliminates sealing defects and improves leak resistance. In addition, since the peripheral edge of the separator is compressed, the amount of electrolyte retained in this area can be reduced, and the amount of electrolyte involved in the reaction can be increased accordingly, stabilizing the internal resistance during discharge. , which increases the discharge reaction efficiency and improves the discharge performance.

EXAMPLE Hereinafter, an example of the present invention will be described using a flat battery having a height of 6.4 fl and a diameter of 23 nm.

Figure 1 is a cross-sectional view of a flat organic electrolyte battery based on lithium manganese dioxide. In the figure, 1 is a stainless steel case that also serves as a positive terminal, 2 is a stainless steel sealing plate, and 3 is an active material. manganese dioxide.

4 is a positive electrode mixture consisting of a conductive agent and a binder; 4 is lithium as a negative electrode active material; 6 is a cross-sectional ring made of polypropylene according to the present invention; 6 is a nonwoven fabric separator made of polypropylene; 7 is a gasket made of polypropylene; 8 is a positive electrode ring made of stainless steel.

The electrolytic solution used was one in which lithium perchlorate was dissolved in a mixed solvent of propylene carbonate and 1,2-dimethoxyethane.

In the conventional battery described above, it is not possible to prevent the occurrence of wrinkling of the separator or poor squeezing, but by using the separator retaining ring 6 of the present invention, the process of squeezing the separator is eliminated and the manufacturing process is stabilized. In addition, the occurrence of sealing defects was eliminated, and the leakage resistance was compared as follows.

The test conditions are the results of 120 cycles of a temperature shock test in which one cycle is 4 hours from -10°C to 60'C.

Number of tests: Number of leaks: Inventive product: 1oo O Conventional product: 1o05 Figure 2 shows the relationship between the battery according to the present invention and the conventional product B, in which the separator is squeezed into a small shape, under a 2.7 Ω load at 20'C. FIG. 3 is a diagram showing a comparison of continuous discharge characteristics. Even if the same amount of electrolyte is used, the separator area of the product of the present invention is approximately 26% smaller than that of the conventional product, so the amount of free electrolyte increases, the reaction efficiency improves, and the discharge time becomes longer. Internal resistance during discharge is stable. In this example, manganese dioxide was used as the positive electrode active material, but other active materials such as fluorides such as fluorocarbon, oxides such as copper oxide, and sulfides such as iron sulfide, which are known as active materials for organic electrolyte batteries, are also used. A mixture molded with a conductive agent and a binder can also be applied in the same way.

Effects of the Invention As is clear from the above explanation, the process is stable and the battery is leak-proof by having a ring with a cross-sectional shape that holds the separator, and inserting a disc-shaped separator into this ring. The effect of improving liquid properties and discharge performance was obtained.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a flat battery in an embodiment of the present invention;
FIG. 2 is a comparison diagram of discharge characteristics between a product of the present invention and a conventional product. 1... Case, 2... Sealing plate, 3...
...Positive electrode, 4...Negative electrode, 6...Ring with inverted cross section (separator holding ring), 6...
... Separator, 7... Gasket, 8.
...Positive ring. Name of agent: Patent attorney Toshio Nakao and one other person
Case 7 - Case Figure 2 Time (Ii)

Claims (1)

[Claims] It has a negative electrode 4 made of a light metal as an active material, a positive electrode 3, a separator 6 interposed between these positive and negative electrodes, and an organic electrolyte. An organic electrolyte battery characterized by comprising a ring 6 having an inverted L-shaped cross section for holding.