JPH0418428B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a non-aqueous solvent battery. [Prior art] Nonaqueous solvent batteries using lithium, sodium, etc. as negative electrode active materials have high energy density, excellent storage characteristics, and a wide operating temperature range, and are used as backup power sources for calculators, watches, and memories. It is often used as. Among these batteries, batteries that use lithium as the negative electrode, sulfur or phosphorus oxyhalide such as thionyl chloride or sulfuryl chloride as the main positive electrode active material, and a positive electrode consisting of carbon and metal current collectors are particularly energy efficient. It is attracting attention because of its high density. By the way, since the above-mentioned battery uses a highly corrosive sulfur or phosphorous oxyhalide such as thionyl chloride or sulfuryl chloride as the main positive electrode active material, the oxyhalide may leak out of the battery container and cause damage to the battery. It is necessary to seal the battery container liquid-tight to prevent corrosion of the stored equipment.
In addition, although the oxyhalide is in liquid form and also serves as an electrolyte, it is highly volatile and highly toxic, so it is important to avoid deterioration of battery characteristics due to the work environment and insufficient capacity of the electrolyte in the container. Therefore, after housing the power generation elements (negative electrode, separator, positive electrode) in the container, it is necessary to inject and store the electrolytic solution containing the oxyhalide in the container. For this reason, conventionally when assembling the above-mentioned battery, the power generation element consisting of the negative electrode, separator and positive electrode is first housed in a metal case which also serves as a unipolar terminal, and then the power generating element consisting of the negative electrode, separator and positive electrode is placed in advance with a sealant of glass or ceramics. A metal lid to which a metal pipe for liquid injection, which also serves as a polar terminal, is liquid-tightly fixed is fitted into the upper opening of the metal can, sealed by laser welding, and then the oxyhalogen is passed through the metal pipe. An electrolytic solution containing a compound is injected into the can, a metal stopper is inserted into the metal pipe, and the end of the pipe protruding from the lid is welded to the stopper to make it liquid-tight. Methods have been devised to close the gap. [Problems to be Solved by the Invention] However, in this method, when welding the end of the metal pipe and the metal stopper, the electrolyte attached to the inner surface of the pipe or the electrolyte in the metal case near the lower end of the pipe is It evaporates due to the heat during welding and enters the space between them as a gas, causing welding defects (often pinholes).
There was a problem that led to a decrease in yield. The present invention has been made in order to solve the above-mentioned conventional problems, and includes a liquid-tight metal pipe for liquid injection that also serves as a terminal of the other polarity and is liquid-tightly fixed to a metal lid via an insulating sealant. The purpose of the present invention is to provide a method for manufacturing a non-aqueous solvent battery having a sealed structure. [Means for Solving the Problems] The present invention includes a step of storing a negative electrode made of a light metal and a positive electrode mainly made of porous carbon in a metal case that also serves as a unipolar terminal, with a separator interposed therebetween, and A metal pipe, which also serves as a terminal of the other polarity, is liquid-tightly fixed to the hole through an insulating material so that the upper end side of the pipe protrudes from the lid. a step of fitting and sealing by welding, a step of accommodating an electrolytic solution containing an oxyhalide as a positive electrode active material in the metal can through the metal pipe, and inserting a metal stopper into the metal pipe, A method for manufacturing a non-aqueous solvent battery comprising a step of sealing an upper end of the metal pipe protruding from the lid and an upper end of the plug by welding, the plug having a flange at an upper end. The plug body is inserted into the metal pipe to bring the collar into contact with the upper end surface of the pipe, and the internal plug is closed by caulking the pipe portion protruding from the metal lid body. After forming an annular constriction toward the body and bringing the inner circumferential surface of the pipe into close contact with the outer circumferential surface of the plug, the upper end surface of the pipe and the flange of the plug that abuts are welded. This is a method for manufacturing a non-aqueous solvent battery, which is characterized in that the battery is sealed using a battery. [Function] According to the present invention, a metal lid member is provided in which a metal pipe that also serves as a terminal of the other polarity is liquid-tightly fixed to a hole near the center through an insulating material so that one end of the pipe projects. , fit into the upper opening of the metal can body,
After the cap is sealed by welding and the electrolyte is accommodated in the metal can through the metal pipe, a metal plug is inserted into the pipe and the flange of the plug is brought into contact with the cap, and the metal cap protrudes from the metal lid. By caulking the pipe portion, an annular constriction toward the inner plug is formed to bring the inner circumferential surface of the pipe into close contact with the outer peripheral surface of the plug, and the upper end surface of the pipe and the abutting portion of the pipe are brought into close contact with each other. Weld the flange of the plug body. Due to the temperature rise during such welding, the electrolytic solution inside the can moves in a gasified or liquefied state from the lower end to the upper end of the metal pipe. This can be prevented by the part that is in close contact with the outer circumferential surface of the plug. the result,
It is possible to manufacture a non-aqueous solvent battery having a good sealing structure without leakage of electrolyte during use by avoiding sealing defects of the metal pipes. [Example] Hereinafter, an example of the present invention will be described in detail with reference to FIGS. 1 and 2. First, the stainless steel can body 1 which also serves as the negative terminal
After a cylindrical negative electrode 2 made of metallic lithium is crimped onto the inner peripheral surface of the lithium metal lithium, the positive electrode 3 is placed inside the negative electrode 2 and over the bottom surface of the can 1, for example. It was housed with separators 4a and 4b made of nonwoven glass fiber fabric interposed therebetween. The positive electrode 3 is
A commercially available polytetrafluoroethylene emulsion was blended with acetylene black at a ratio of 10% by weight, water and ethyl alcohol were added, and the mixture was stirred at room temperature for about 2 hours, then kneaded and formed into a sheet. The sheet was dried under vacuum at 150° C. to form a band-like body having a porous carbon body 6, and this was produced by winding it into a smooth spiral shape. Next, an insulating paper 7 having a hole in the center and supported by the separator 4a was placed in the can 1 above the positive electrode 3. Next, a stainless steel pipe 10 for liquid injection, which also serves as a positive electrode terminal, is liquid-tightly fixed to the hole 9 opened in the center with a glass sealant 11 so that the upper and lower ends protrude. After preparing a lid 8 and connecting the lower end of the pipe 10 fixed to the lid 8 to the metal current collector 5 of the positive electrode 3 via a lead wire 12, a They were fitted and sealed using a laser solution. Next, a thionyl chloride solution (electrolyte) 13 in which, for example, 1.5 mol/LiAlCl ₄ was dissolved was injected into the can body 1 through the pipe 10 and housed therein.
Next, as shown in FIG. 2, a stainless steel stopper 15 having a flange 14 having the same diameter as the outer diameter of the pipe 10 at its upper end is prepared, and the stopper 15 is inserted into the stainless steel pipe 10. The pipe was inserted until the collar 14 came into contact with the upper end surface of the pipe 10. Subsequently, the portion of the pipe 10 protruding from the lid 8 is caulked to form an annular constriction 16 toward the stopper 15 inside the pipe 10.
After bringing the inner circumferential surface of the stopper 15 into close contact with the outer circumferential surface of the stopper 15,
The non-aqueous solvent battery shown in FIG. 1 was manufactured by sealing the upper end surface of the pipe 10 and the flange 14 of the stopper 15 in contact therewith by laser welding. According to the above-described method, before the stainless steel pipe 10 for liquid injection which also serves as a positive electrode terminal and the stainless steel stopper 15 are sealed by welding, the pipe 10 is
In order to form an annular constriction 16 toward the inner plug body 15 by caulking to bring the inner circumferential surface of the pipe 10 and the outer circumferential surface of the plug body 15 into close contact, the inside of the can body 1 must be melted when sealing by welding. The liquid 13 is in a gasified or liquefied state due to the temperature rise during welding, and the pipe 1 is
0 movement to the upper end can be prevented by the close contact portion between the pipe 10 and the plug 15 of the constricted portion 16. Furthermore, even if the electrolyte should enter the upper side through the contact portion, a flange portion 14 is formed at the upper end of the plug body 15, and the brim portion 14 is brought into contact with the upper end surface of the pipe 10 to seal it. Therefore, the electrolyte can be stopped just before the relevant contact point. As a result, the constricted portion 16
This is because the electrolyte is stopped at two places, the close contact part and the lower surface of the flange 14, and it is possible to prevent the electrolyte from adhering between the upper end surface of the pipe 10 to be welded and the flange 14 of the plug 15. By laser welding, it is possible to obtain a non-aqueous solvent battery with good sealing without the occurrence of pinholes. In fact, the battery manufactured according to this example and the battery manufactured by inserting a stainless steel plug without a flange into a stainless steel pipe and sealing it by welding the top of the pipe and the top of the plug (Comparative Example 1) A stainless steel stopper without a flange is inserted into a stainless steel pipe, and the part of the pipe protruding from the cover is caulked to form an annular constriction toward the inner stopper, thereby connecting the inner peripheral surface of the pipe and the stopper. We prepared 200 batteries each (Comparative Example 2), which were manufactured by making the outer peripheral surfaces in close contact with each other, and then sealing the upper part of the pipe and the upper part of the plug by welding.
These batteries were tested for the occurrence of pinholes in the sealing portion due to welding. The test was conducted by dropping a silver nitrate solution, which is a chloride ion detection indicator, onto the welded area and measuring the number of pieces showing white coloration. As a result, in Comparative Example 1, pinholes (white coloration) were observed in 14 out of 200 batteries, and in Comparative Example 2, pinholes were observed in 3 out of 200 batteries. In contrast, in this example, no pinholes were observed in all 200 samples. In addition, in the above example, a plug body having a flange having the same diameter as the outside diameter of the pipe was used, but a flange that is slightly smaller than the outside diameter of the pipe or slightly larger than the outside diameter of the pipe may also be used. good. [Effects of the Invention] As described in detail above, according to the present invention, a flange is provided at the upper end of a metal pipe for liquid injection that also serves as a terminal of the other polarity and is liquid-tightly fixed to a metal lid via an insulating sealant. inserting a plug body having a shape, and caulking the pipe portion protruding from the lid body to form an annular constriction toward the internal plug body to bring the inner peripheral surface of the pipe and the outer peripheral surface of the plug body into close contact with each other. Furthermore, by welding the upper end surface of the pipe to the flange of the stopper that comes into contact with it, the pipe can be sealed liquid-tightly, and as a result, the electrolyte inside the metal case does not leak out during use. It is possible to provide a method for manufacturing a non-aqueous solvent battery having a sealed structure with high yield.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a non-aqueous solvent battery manufactured according to an embodiment of the present invention, and FIG. 2 is a front view showing a metal stopper used in manufacturing the non-aqueous solvent battery shown in FIG. 1. . 1... Can body, 2... Negative electrode, 3... Positive electrode, 4a, 4b...
Separator, 8... Lid, 10... Stainless steel pipe, 13... Electrolyte, 14... Flange, 15... Plug, 1
6... Constriction.

Claims (1)

[Claims] 1. A step of storing a negative electrode made of a light metal and a positive electrode mainly composed of porous carbon in a metal case that also serves as a unipolar terminal via a separator, and placing a terminal of another polarity in a hole near the center in advance. A metal lid, which is liquid-tightly fixed via an insulating material so that the upper end side of the metal pipe that also serves as a pipe protrudes from the lid, is fitted into the upper opening of the metal can body and welded. a step of accommodating an electrolytic solution containing an oxyhalide as a positive electrode active material in the metal can through the metal pipe; and a step of inserting a metal plug into the metal pipe and protruding from the lid. A method for manufacturing a non-aqueous solvent battery comprising the step of sealing the upper end of the metal pipe and the upper end of the plug by welding, using a plug having a flange at its upper end, This plug body is inserted into the metal pipe and the collar portion is brought into contact with the upper end surface of the pipe, and the pipe portion protruding from the metal lid body is caulked to form an annular constriction toward the internal plug body. After the inner circumferential surface of the pipe and the outer circumferential surface of the plug are brought into close contact with each other by forming a section, the upper end surface of the pipe and the flange of the plug that comes into contact with the upper end surface of the pipe are sealed by welding. A method for manufacturing a non-aqueous solvent battery.