JPS6196653A - Manufacture of sealed battery - Google Patents

Abstract

PURPOSE:To reliably seal the pipe by subjecting the pipe to laser welding while holding it by a few position-restricting plates which can be freely attached to or detached from the pipe. CONSTITUTION:After a liquid electrolyte is poured into the sealed battery through a pipe 5 fused to the inner area of the insulating layer 4 of a battery lid 2 by vacuum impregnation, a current collector bar 11 is inserted into the pipe 5. While holding the pipe 5 between two position-restricting plates 12a and 12b which can be freely attached to or detached from the pipe 5, a laser beam 13 is irradiated in the axial direction of the pipe 5 to fuse the upper end of the pipe 5 and the head of the bar 11 thereby sealing the pipe 5. Even when light scattering from the laser beam 13 leaks outside the pipe 5, the plates 12a and 12b prevent the laser beam 13 from being applied to the insulating layer 4.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a sealed battery employing a hermetic seal structure.

[Conventional technology]

For example, in batteries such as thionyl chloride-lithium batteries that require a high degree of airtightness, a hermetic seal is used, and the battery container and the battery 7t111 are joined by welding. After welding the battery container and the battery lid, the electrolyte is press-fitted through a pipe that is separated from the battery lid or the battery container through an insulating layer, and
After electrolysis/injection, the pipe is welded and sealed.

When welding a vibrator seal like the one mentioned above, the laser beam can be narrowed down to a small size, making it extremely difficult to weld! It is used as a welding heat source because the heat effect on the iFi and battery contents is small, and the welding and sealing of the pipe after injecting the electrolyte is similar to the 78 connection between the battery lid and the battery container, and the battery is connected to the outer periphery of the battery. This is done by placing the pipe in a holder with a concave portion that matches its shape, and irradiating a laser beam from the axial direction of the pipe at a certain position where the pipe is expected to be located (unspecified literature).

(Problem to be solved by the invention) However, since battery containers are generally made from stainless steel plates by deep drawing, dimensional errors and deformations are likely to occur, and as a result, the electrolyte injection pipe is located at the center of the battery container. The desired part of the injection pipe to be welded may not match the laser beam irradiation position, resulting in incomplete welding, or the laser beam may be applied to the periphery of the injection pipe, making it difficult to weld glass or ceramics. There is a problem that the insulating layer covered by the battery is damaged and the hermeticity of the battery is impaired.

[Means for solving problems]

The present invention is intended to solve the above-mentioned problems of the prior art, and is aimed at welding and sealing a pipe after injecting an electrolyte into the sealed battery. By laser welding the pipe while controlling its position with the position regulating member, the desired part of the pipe to be in contact with F4 matches the irradiation position of the laser beam, and the heat does not affect the peripheral parts of the pipe, such as the insulating layer and battery container. First, the pipe can be reliably welded and sealed.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

Fig. 1 is a partial sectional view showing a sealed battery being manufactured by the method of the present invention, Fig. 2 is a perspective view showing the movement of the position regulating member, and Fig. 3 is a completed welding sealing of the pipe. FIG.

In these figures, l is a stainless steel battery container,
2 is a battery lid, 3 is the main body of the battery lid made of stainless steel and generally called the body, 4 is an insulating layer made of glass, 5 is a pipe made of stainless steel mesh, and 6 is made of lithium. 7 is a separator made of glass fiber nonwoven fabric, 8 is a positive electrode made of a carbon porous molded body, 9 is a cover paper made of glass TDH fiber nonwoven fabric, and 10 is an electrolyte prepared by dissolving lithium aluminum tetrachloride in thionyl chloride. 1
&, 11 is a current collector rod made of stainless steel, 12a and 12b are position regulating members made of copper, and 13 is a laser beam.

This battery is manufactured as follows.

Put the negative electrode 6, the separator 7, a bottom paper (not shown) made of the same material as the separator 7, and the positive electrode 8 into an 11Wh capacity RA 1, fit the battery cover 2 into the opening of the battery case 1,
The rising edge of the outer periphery of the battery lid 2 and the open end of the battery container 1 were welded together, and electrolyte was injected into the battery by vacuum impregnation through a pipe 5 that had been welded in advance to the inside of the insulation N4 of the battery M2. After that, the current collecting rod 11 is inserted into the pipe 5, and the pipe 5 is held while being controlled by the two position regulating members 12a and 12b that are provided so as to be able to move toward and away from the cough pipe 5, and the laser beam 13 is A battery is manufactured by irradiating the pipe 5 from the axial direction and welding the upper end of the pipe 5 and the head of the current collector rod 11 to seal the pipe 5 by welding.

In this embodiment, the position regulating members 12a and 12b are plate-shaped, and a concave portion having a shape that matches the outer circumference of the pipe 5 is provided on the surface that contacts the pipe 5, and these two position regulating members 12a,
12b go from a discrete state as shown in FIG. 2 fat to gather as shown in FIG.

These position regulating members 12a and 12b not only regulate the position of the pipe 5, but also cover the periphery of the pipe 5 during laser beam irradiation, so that the scattered light of the laser beam does not leak to parts other than the pipe. Even if this happens, the laser beam is prevented from hitting the insulating layer 4 or the like.

Furthermore, the position regulating members 12a and 12b function to absorb the heat of the pipe 5 heated by the laser beam through thermal conduction by making strong contact with the pipe 5, and thereby suppress heating of parts other than the desired welding part. This has the effect of reducing the heat effect on the surrounding area.

The material of the position regulating members 12a, 12b is not particularly limited in terms of position regulating function, and various materials can be used. However, considering other characteristics, materials that have low laser beam absorption and thermal conductivity should be used. Good copper or copper alloys are preferred, such as German silver, brass, bronze, aluminum bronze, beryllium copper, and the like.

In this embodiment, two position regulating members are provided, and the pipe 5 is positioned by a set of 21 m1 of position regulating members 12a, 12b, but it is also possible to use three or more position regulating members. If the function of the position regulating member is small, the part that contacts the outer periphery of the pipe 5 when the position regulating member is assembled needs to be formed into a concave shape that matches the outer periphery of the pipe 5 as shown in the figure. .

By the method of the present invention shown in the above embodiment and the conventional method (a method in which the battery is placed in a holder having a recess that matches the shape of the battery's outer periphery and the pipe is welded and sealed), an AA battery can be placed in the center of the battery container. Laser welding the pipe of a battery whose pipe is eccentric by O, lam (outer diameter l).

Table 1 shows the results of investigating the number of welding defects when a 5 mm pipe was sealed with a laser output of 1 kW and a laser beam irradiation time of 0.2 seconds.

Table 1 As shown in Table 1, according to the method of the present invention, there is no occurrence of welding defects, and even if the pipe is eccentric to the center of the battery container, the sealing by laser/8 contact is reliable. It was revealed that it can be done.

In the embodiment, one current collector rod 11 was placed in the pipe 5, and the upper end of the pipe 5 and the head of the current collector rod 11 were laser welded to seal the pipe 5, but it is not necessary to insert the current collector rod II. Alternatively, the upper end of the pipe 5 may be temporarily sealed by crushing it, and then completely sealed by laser welding. Further, in the embodiment, the pipe 5 is provided in the battery M2, but the present invention is also applicable to a case in which the pipe 5 is provided in the battery container l.

〔Effect of the invention〕

As explained above, according to the present invention, even if the pipe is eccentric with respect to the center of the battery container, reliable laser welding sealing is possible, and the scattered light of the laser beam is prevented from hitting areas other than the periphery of the pipe. In addition, heating of areas other than the welded portion can be suppressed by the heat transfer action of the position regulating member.

[Brief explanation of drawings]

FIG. 1 is a partial sectional view showing a sealed battery being manufactured by the method of the present invention, FIG. 2 is a perspective view showing the movement of the position regulating member, and FIG. State, Fig. 2 (bl shows the state in which the position regulating members are assembled and sandwiching the pipe, No. 31i8!l is a cross-sectional view showing the main parts of the battery after the pipes have been welded and sealed. 1.・Battery container, 2...Battery lid, 3...Body part, 4...Insulating layer, 5...Pipe, lO...
・Electrolyte solution, 11... Current collector rod, 12a, 12b...
Position regulating member, 13... laser beam

Claims (2)

[Claims] (1) Electrolyte is injected into the battery lid 2 or battery container 1 through a pipe 5 provided through an insulating layer 4, and after the electrolyte is injected, the pipe 5 is inserted from the axial direction of the pipe 5. In manufacturing a sealed battery that is welded and sealed by laser irradiation, a plurality of position regulating members 12a are provided such that the pipe 5 after the electrolyte is injected can be freely moved toward and away from the pipe 5.
, 12b, and clamping and laser welding are performed while positionally regulating the battery. (2) The method for manufacturing a sealed battery according to claim 1, wherein a metal rod is inserted into the pipe 5, and the upper end of the pipe 5 and the metal rod are laser welded.