JPH0215559A - Manufacture of nonaqueous solvent battery - Google Patents

Abstract

PURPOSE:To permit the manufacture of a nonaqueous solvent battery having structure formed through liquid-tightly sealing the opening of an electrolyte filler pipe made of metal also serving as the other polar terminal, by using as a plug body a member in shape having its flange portion abutting on the upper end surface of a metallic pipe at the top of the plug body and also its swelled part in close contact with the inner circumferential surface of the metallic pipe. CONSTITUTION:A covering body 8 made of metal having a pipe 10 made of metal serving also as the other polar terminal liquid-tightly fixed previously in a hole near the center of the covering body via an insulating material such that one end side of the pipe 10 may be projected, is engaged with the upper opening of a metallic canister body 1 for sealing the opening by means of welding. After electrolyte 13 is received via the pipe 10 made of metal into the metallic canister body 1, a plug body 16 made of metal having its flange portion 14 at the top and also its swelled part 15 on the lower part side from the top is press-fitted into the pipe 10, and also the upper end surface of the pipe 10 made of metal is welded to the flange portion 14 of the plug body 16 abutting on the upper end surface. This makes it possible to manufacture a nonaqueous solvent battery having an excellently sealed structure which is formed to avoid any poor seal of the opening of the pipe made of metal so as to cause no leak of the electrolyte in use.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for manufacturing a non-aqueous solvent battery.

[Conventional technology] Nonaqueous solvent batteries using lithium, sodium, etc. as negative electrode active materials have high energy density, excellent storage characteristics,
It also has a wide operating temperature range, and is often used as a backup power source for calculators, clocks, and memory. 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 generating 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 a negative electrode, a separator, and a positive electrode is first housed in a metal case that also serves as a unipolar terminal, and the other polarity terminal is connected in advance with a glass or ceramic sealant. A metal lid to which a metal pipe for liquid injection, which also serves as a liquid injection pipe, is fixed liquid-tightly is fitted into the upper opening of the metal can, and the lid is sealed by laser welding, and then the liquid containing the oxyhalide is passed through the metal pipe. An electrolytic solution is injected and contained in the can, a metal stopper is inserted into the metal pipe, and the end of the pipe protruding from the lid and the stopper are liquid-tightly sealed by laser welding. A method has been considered.

[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 in the tube inside the pipe or the electrolyte in the metal can near the lower end of the pipe is This evaporates due to the heat during welding and enters the gaps in the form of a gas, causing welding defects (often pinholes), resulting in a reduction in yield.

The present invention has been made in order to solve the above-mentioned conventional problems, and the present invention has been made to liquid-tightly fix a metal pipe for liquid that also serves as a terminal of the other polarity, which is liquid-tightly fixed to a metal lid through an insulating sealing material. The present invention aims to provide a method for manufacturing a non-aqueous solvent battery with 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 composed of porous carbon in a metal case that also serves as a unipolar terminal, with a separator interposed therebetween, and A metal lid, in which a metal pipe that also serves as a terminal of the other polarity is liquid-tightly fixed to the hole through an insulating material so that one end of the pipe protrudes in advance, is fitted into the upper opening of the metal can. a step of accommodating an electrolytic solution containing an oxyhalide as a positive electrode active material into the metal can through the metal pipe; and a step of inserting a metal stopper into the metal pipe and sealing the lid by welding. In the manufacturing of a non-aqueous solvent battery, the step includes sealing the metal pipe end portion protruding from the metal pipe and the plug body by welding, the flange portion being in contact with the upper end surface of the metal pipe at the upper end as the plug body. and a shape having a bulge that closely contacts the inner circumferential surface of the metal pipe, and weld the upper end surface of the metal pipe and the flange of the plug that is in contact with the upper end surface of the metal pipe. This is a method for manufacturing a non-aqueous solvent battery, characterized in that the battery is sealed.

[Function] According to the present invention, a metal lid body is fixed in advance to a hole near the center in a liquid-tight manner through an insulating material so that a metal pipe that also serves as a terminal of the other polarity projects from one end side of the pipe. , after fitting into the upper opening of the metal can and sealing it by welding, and storing the electrolytic solution in the metal can through the metal pipe, the pipe has a flange at the upper end and a flange below the upper end. By press-fitting a metal stopper that covers the bulging part and welding the upper end surface of the metal pipe to the flange of the stopper that is in contact with the top end surface of the metal pipe, sealing failure of the metal pipe can be avoided. A non-aqueous solvent battery can be manufactured that has a good sealing structure that prevents leakage of electrolyte during use.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to FIGS. 1 and 2.

First, a cylindrical negative I! made of metallic lithium is placed on the inner peripheral surface of a stainless steel can body 1 which also serves as a negative electrode terminal. After compressing 1Ji2 into a pressure tube, the positive electrode 3 is placed in a can l inside the negative electrode 2 through separators 4a and 4b made of a nonwoven fabric made of glass fiber, for example, which are arranged over the inside of the negative electrode 2 and the bottom surface of the can l. I put it away. The positive electrode 3 was prepared by blending a commercially available polytetrafluoroethylene emulsion with acetylene black at a ratio of 10% by weight, adding water and ethyl alcohol, stirring at room temperature for 2 hours, and then kneading and forming into a sheet. The porous carbon body 6 is pressed onto a metal current collector 5 made of a stainless steel net, and the sheet is dried under a vacuum of 150'c to form a porous carbon body 6 into a G belt-like body, which is wound in a spiral shape. It was made by

Next, the separator 4 is placed in the can 1 above the positive electrode 3.
An insulating paper 7 having a hole in the center was placed supported by a.

Next, a stainless steel lid is fixed liquid-tightly through a glass sealing material 11 so that a stainless steel pipe 10 for liquid injection, which also serves as a positive terminal, is protruded from the upper and lower ends of the hole 9 opened in the center. After preparing a body 8 and connecting the lower end of the pipe 10 fixed to the lid body 8 to the metal current collector 5 of the positive electrode 3 via a lead wire 12, the pipe 10 is fitted into the upper opening of the can body l. and sealed by laser welding.

Next, a thionyl chloride solution (electrolyte) +3 in which, for example, 1.5 mol/g of LiAjJCII4 was dissolved was injected into the can body 1 through the pipe 10 and housed therein. Continuing, as shown in FIG. 2, the upper end has a flange 14 having a diameter slightly larger than the outer diameter of the pipe 1O, and the flange 14 has a diameter slightly larger than the outer diameter of the pipe 1O, and is located near the center below the upper end by 1.0 mm larger than the inner diameter of the pipe 1O.
Prepare a stainless steel stopper 16 having a spherical bulge 15 that is 2++ m large, press fit the stopper 16 into the stainless steel pipe 10 until the collar 14 comes into contact with the upper end surface of the pipe IO, The bulging portion 15 is connected to the pipe 10.
The non-aqueous solvent battery shown in FIG. 1 is manufactured by sealing the upper end surface of the pipe IO and the flange 14 of the stopper IG that is in contact therewith by laser welding. did.

According to the method described above, before the stainless steel pipe 1o for liquid injection, which also serves as a positive terminal, and the stainless steel stopper 16 are sealed by welding, the stopper IG is attached to the inner peripheral surface of the pipe 10.
In order to make the bulging part 15 of the can tightly fit, when sealing by welding, the inner periphery of the pipe 10 prevents the electrolyte 13 in the can l from moving to the upper end of the pipe 10 in a gasified or liquefied state due to the temperature rise during welding. This can be prevented by the close contact between the surface and the bulge 15 of the plug 1G. However, even if the electrolyte enters the upper side through the sealing part, the upper end of the plug body 16 will not have the flange part 14.
is formed and is sealed by contacting the upper end surface of the pipe IO, so that the electrolyte can be stopped just before the corresponding contact part. As a result, electrolytic solution IL is formed at two places, the contact area and the lower surface of the flange 14, and the electrolyte is deposited between the upper end surface of the pipe 10 to be welded and the flange 14 of the plug te. Since this can be prevented, it is possible to obtain a non-aqueous solvent battery with good sealing without the occurrence of pinholes by laser welding.

In fact, a battery manufactured according to this example and a battery manufactured by inserting a stainless steel plug without a flange or a bulge into a stainless steel pipe and sealing the pipe by welding the top of the pipe and the top of the plug (comparison) Example 1) and a battery manufactured by inserting a stainless steel stopper having only a bulge into a stainless steel pipe and sealing the pipe by welding the top of the pipe and the top of the stopper (Comparative Example 2).
) were prepared, and these batteries were tested for the presence or absence of pinholes in the sealing part 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, 14 out of 200
Pinholes (white coloring) were observed in some batteries.
In Comparative Example 2, pinholes were observed in 2 out of 200 batteries. On the other hand, in this example, 200 pieces total 7
No pinholes were observed.

In addition, in the above example, a plug body having a flange having a diameter slightly larger than the outside diameter of the pipe was used, but it is also possible to use a flange having the same diameter as the outside diameter of the pipe, or a flange having a diameter slightly smaller than the outside diameter of the pipe. You can.

Also, the diameter of the bulging portion of the plug is 1.0 mm larger than the inner diameter of the pipe. O
It is preferable to increase it by 1 to 1.03 as+. The reason for this is that if the diameter is less than l, OLam, sufficient adhesion between the bulge and the inner peripheral surface of the pipe cannot be achieved, but if the diameter exceeds 1.03 m, the pipe may be damaged. This is because there is.

In the above embodiment, the metal stopper has a spherical bulge near the center, but it may also have an inverted conical bulge near the center. Alternatively, a plug 16 having a spherical bulge 15 formed at the lower end as shown in FIG. 3, or a plug 1B having an inverted conical bulge 15 formed at the lower end as shown in FIG. You can.

[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. The pipe is sealed liquid-tightly by inserting a plug having a bulge and a bulge below the lid, and welding the upper end surface of the pipe protruding from the lid to the flange of the plug. We propose a method for producing at high yield a non-aqueous solvent battery that has a good sealing structure that prevents electrolyte from leaking inside the metal case during use.
"(can.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a non-aqueous solvent battery manufactured according to an embodiment of the present invention, FIG. 2 is a sectional view showing a metal stopper used in manufacturing the non-aqueous solvent battery shown in FIG. 3 and 4 are sectional views of metal stoppers showing other embodiments of the present invention, respectively. l...04 body, 2...negative electrode, 3...positive electrode, 4a,
4b... Separator, 8... Lid, 10... Stainless steel pipe, 13... Electrolyte, 14... Flange, 15... Swelling part, 16... Stopper. Applicant's agent Patent attorney Takehiko Suzue Figure 1 Figure 2 Figure 3 Figure 4 b

Claims (3)

[Claims] (1) The process 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 a metal case that also serves as a terminal of other polarity in advance in a hole near the center. A metal lid body is fixed liquid-tightly through an insulating material so that the pipe protrudes from one end side of the pipe,
a step of fitting into the upper opening of the metal can and sealing it 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; Insert the metal stopper,
In manufacturing a non-aqueous solvent battery, the step includes sealing the end portion of the metal pipe protruding from the lid body and the plug body by welding. The top end surface of the metal pipe and the flange of the plug that is in contact with the upper end surface of the metal pipe are used. A method for manufacturing a non-aqueous solvent battery, comprising welding and sealing the battery. (2) The method for manufacturing a non-aqueous solvent battery according to claim 1, wherein the bulging portion of the metal stopper is spherical. (3) The method for manufacturing a non-aqueous solvent battery according to claim 1, wherein the bulging portion of the metal stopper has an inverted conical shape.