JPS59138070A - Lithium battery - Google Patents

Abstract

PURPOSE:To suppress temperature increase inside a battery and decrease pressure increase inside the battery and danger of battery rupture by arranging metal plates for heat radiation in an electrode plate group. CONSTITUTION:A disc-shaped lithium-thionyl chloride battery is assembled in such a way that an electrode group is accommodated in a battery cases 1 and 2 which also act as a positive terminal and their circumferences are welded by plasma arc to seal them. 6 shows a positive current collector comprising acetylene black and nickel expanded metal and one end of the expanded metal is spot- welded to the cases 1 and 2. 7 shows a lithium negative electrode which is connected to a negative terminal 4 by spring action of nickel current collector which is pressed to the center of the negative electrode. 8 indicates a separator, which holds thionyl chloride solution acting as a positive active material and an electrolyte, comprising a glass nonwoven sheet. 10 shows heat radiation plates comprising a 0.1mm. thick nickel plate and placed between positive current collector 6, and their circumferences are spot-welded to the cases 1 and 2. Therefore, heat generation in current collector of both electrode and that in separator caused by iR drop by electrolyte resistance are radiated to the battery cases to suppress temperatue increase inside the electrode group.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improving a lithium battery using lithium as a negative boiling active material. The purpose of this product is to prevent temperature changes and rises in the battery and to prevent dangers such as battery explosion.

Due to the remarkable progress in electronics in recent years, there are demands for batteries to be smaller, lighter, and have higher performance.
12 is its good energy 'PA degree.

It is extremely luxurious and attracts attention due to its power density, low temperature performance, and storage performance. However, since this battery uses lithium, it is limited by the electrolysis used, and the electrolyte uses some organic M medium that has poor reactivity with lithium, thionyl chloride, or a mixed solvent of sulfur dioxide and acetonitrile. Because its internal resistance is normal acid, alkali IJ
It has the disadvantage that it is larger than an It cell, and it is difficult to perform large current density discharge. For this reason, batteries are usually made by winding the positive and negative electrodes into a spiral shape with a separator in between, or into a disc-shaped li! A large number of ll plates are stacked with separators in between to make the surface larger, thereby making it possible to generate a large electrical discharge.

However, there are limits to these countermeasures since the electrolyte resistance is large, and when discharging at a current density of 10+nA/cd or higher, the internal resistance Due to the new light and heat, the crux temperature rises and the vapor pressure of the electrolyte rises, resulting in an increase in the internal pressure of the battery and a dangerous situation.
Or, if the discharge is continued further, the temperature will drop to the melting point of lithium (1
There is also the danger that the lithium may reach 78"C) and cause an explosion due to melting of the lithium.

Therefore, in order to prevent these dangers during high-rate discharge, it is necessary to prevent the ripening of the tl (r ton field from accumulating in the facing plate group) and letting it escape to the outside through the 2111 case. be.

The present invention is capable of solving these 11 problems, and the following-
This will be explained based on examples. FIG. 1 is a longitudinal cross-sectional view of a disk-shaped lithium thionyl chloride battery having a diameter of 75 m and a height of 16 mm and having a heat sink according to the present invention. In the figure (11, (2
1 is a battery case that also serves as a self-contained terminal (both from SUE 804), and after housing the excited group, the entire circumference is bath-welded by a plasma arc and is integrated with a marsh seal. (3
) is a negative l! consisting of two terminals (1) and two l Kel! ! ll terminal (4) electrically separated by 1'! ii As time goes by, the battery pressure rises above the standard,
The 1α pond was damaged at 15:00, and it acts as a safety valve to release the circular pressure to the evening. (5) is a gage tube that is welded to a part of the battery case, and it also serves as a pressure active material in the N pond.
After injecting thionyl chloride into the W electrolyte, one end of it is sealed by welding. (6) is a positive body made of acetylene chloride extract band metal, and one end of the nickel extract band metal is spot-welded to the battery cases (1) and (2). In this embodiment, ten knee current collectors are used. (7) is a negative terminal made of lithium, with a nickel current collector crimped to its center, which is integrated with the negative terminal (4) by the spring action of the nickel current collector. In this embodiment, five lithium negative plates are used. (8)
is a separator made of glass nonwoven fabric that holds thionyl chloride, an electrolyte that also serves as a positive active material.

(9) is the number of lower insulation made of glass cloth. (10)
is a heat dissipation plate based on the present invention, which is made of a nickel plate with a thickness of 0.1 mm, is placed between the regular current collectors (6), and is integrally connected to the battery cases (11, (21) by spot bath welding). has been made into

Generally, when a lithium battery is discharged, the lithium electric current becomes lithium ions and is released into the liquid, and the fresh lithium surface is always in contact with the electrolyte, so the fraction is very small, and therefore the activation/closing fraction of the lithium battery is large. The portion is due to the normal image side. For this reason, the heat generated from the battery is greater from the normal image side, and it is preferable to place the heat sink on the 1L side. As shown in Figure 1, the heat sink is placed in contact with the positive current collector.
First, the heat generated by the positive dyed electrode or the iR draw knob caused by the electrolyte resistance in the separator part is released to the battery case part, and as a result, the temperature rise inside the ghost meter is effectively suppressed. It is intended to suppress

Next, the diameter of the configuration based on this implementation e and u is 75 mm and the thickness is 16 mm.
When continuous discharge of 2OA was carried out at room temperature using a disc-shaped lithium thionyl chloride battery (7) of M and a conventional lithium thionyl chloride battery (a) with the same size of 7. (I!ll Temperature rise 1 month and other swelling, group 7I!The pressure comparison is 21st chrysanthemum, and iR temperature in Figure 3.)

As is clear from this, the temperature rise and blistering of the T-section according to the present invention are smaller than those of conventional batteries, and the effect of the heat sink of the present invention is clear. Although the mafco discharge is somewhat lower in the present invention due to less temperature rise, there is no significant difference.

The above mentioned about the salt 1tZ thionyl lithium battery has this effect [711! This is not limited to, but is common to 1 m organic electrolyte-based or inorganic electrolyte-based lithium batteries.

The present invention effectively suppresses the temperature rise inside the battery, thereby effectively reducing the dangers such as rise in deep pond internal drying and tX curve explosion, and its industrial equivalent (1 It is extremely large.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a thionyl chloride lithium battery according to the present invention, and FIG. 2 shows a thionyl chloride lithium battery according to the present invention and a conventional thionyl chloride lithium battery.
A: Comparative temperature rise diagram and comparative battery bulge diagram during discharge. Figure 3 shows the 2OA release vI of the thionyl chloride lithium battery according to the present invention and the conventional thionyl chloride lithium battery.
It is a comparative characteristic diagram at the time of E. 1.2...Battery case (don't worry about the original terminal) 4
......Electric terminal, 6...... Positive mesh current collector. 7...Lithium negative-18...Glass separator 10...Heat sink.

Claims (1)

[Claims] Wrap the positive and negative bits in a spiral, or ell multiple pieces of them.
1- Do it [Using the lithium pride that is the same as Idun's revision:
A lithium battery characterized in that in tEtm, a metal plate for heat dissipation is arranged in the bite plate group.