JPH0530022B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an improvement in a method for manufacturing a lithium battery, which facilitates insertion of a lithium cylindrical body into a metal container. This prevents lithium from adhering to the open end of the tube.

BACKGROUND ART In a lithium battery, a method for attaching a lithium negative electrode to a metal container is to use a lithium cylindrical body with approximately the same dimensions as the inner surface of the metal container, and to attach a thin metal pedestal to the bottom of the lithium cylindrical body. A device that prevents lithium from adhering to the open end of the battery container when inserting lithium (Japanese Unexamined Patent Application Publication No. 1989-1981)
-5569) or by crimping a wire mesh to the outer circumferential surface of the lithium cylindrical body and inserting it into the metal container in this state, prevents direct contact between lithium and the inner surface of the metal container, and prevents the opening of the battery container. A device that prevents lithium from adhering to the end portion (Japanese Patent Application Laid-open No. 59-5568) has been proposed.

Problems to be Solved by the Invention Metallic lithium is a soft metal and has the property of coming into close contact with other metals when strongly pressed, and the property of easily deforming with a small force. These properties of metallic lithium are both advantageous and problematic in the production of lithium batteries. When inserting a lithium cylindrical body into a metal container and bringing it into close contact, if a lithium cylindrical body is used that has an outer surface shape that is approximately the same as the inner surface shape of the metal container, it is extremely difficult to insert the lithium cylindrical body into the metal container. In addition, to prevent lithium from adhering to the open end of the metal container during insertion, a thin metal pedestal is attached to the bottom of the lithium cylinder, or a wire mesh is crimped to the outer circumferential surface of the lithium cylinder. There were problems such as the need for extra parts and processes.

Means for Solving the Problems The present invention uses a lithium cylindrical body whose outer diameter is smaller than the inner diameter of the metal container, and after inserting the lithium cylindrical body,
A hollow rubber body having an outer diameter smaller than the inner diameter of the lithium cylindrical body is inserted into the lithium cylindrical body, and the hollow rubber body is expanded by increasing the internal pressure of the lithium cylindrical body. This method is characterized by deforming the shaped body and press-fitting it into the metal container.

Function In bobbin-type box-shaped or cylindrical lithium batteries, electrical connection between the lithium and the container is made by pasting the lithium on the inner surface of the metal container or adhering it tightly by crimping.

By effectively utilizing the elastic deformation properties of rubber, the present invention allows lithium to adhere to the inner surface of a metal container in a simple process, and also prevents lithium from adhering to the open end of the metal container. This is how it was done.

EXAMPLE FIG. 1 is a sectional view of a bobbin type cylindrical lithium battery manufactured by the method of the present invention, in which 1 is a metal container and 2 is a lithium negative electrode. A method of bringing the lithium negative electrode into close contact with the metal container will be explained with reference to FIG.

A lithium cylindrical body 2' having an outer diameter D2 smaller than the inner diameter D1 of the metal container 1 is inserted into the metal container, and a hollow rubber body 101 having an outer diameter D4 smaller than the inner diameter D3 of the lithium cylindrical body 2' is inserted into the metal container 1. The hollow part 104 of the hollow rubber body is inserted into the cylindrical body.
from the compressor 103 to the pressurizing valve 102
Add air pressure of about 10 atmospheres. The hollow rubber body expands and deforms as the internal pressure increases, and acts in the direction of pressing the lithium against the metal container. Due to this compressive force, the lithium sticks tightly to the inner surface of the metal container and does not come off.

Next, by returning the pressure in the hollow part of the hollow rubber body to atmospheric pressure, the outer diameter D4 of the hollow rubber body returns to its original size and separates from the lithium cylindrical body. The hollow rubber body can be taken out of the battery and used to manufacture the next battery.

After the lithium cylindrical body is brought into close contact with the inner surface of the metal container, a side separator 3 and a bottom separator 4 made of glass fiber are arranged, and a positive electrode 5 formed by adding tetrafluoroethylene resin to acetylene black as a binder is placed. . 6 is a current collector made of nickel wire mesh placed on the inner surface of the positive electrode. A liquid injection tube 8 is attached to the battery cover 7 via a glass insulator 12. The metal container 1 and the battery cover 7 are made of stainless steel and are welded together at a joint 10 to seal the battery. The liquid injection tube 8 also serves as a positive electrode terminal, and a lead wire 9 of the positive electrode current collector 6 is passed through it. After welding the metal container and the battery cover, thionyl chloride in which LiAlCl4 is dissolved is injected from the liquid injection tube, and then the tip 11 of the liquid injection tube is welded together with the lead wire 9 and sealed.

Effects of the Invention As described above, since the present invention inserts a lithium cylindrical body having an outer diameter smaller than the inner diameter of the metal container into the metal container, this insertion process is extremely easy.
In addition, since a hollow rubber body with an outer diameter smaller than the inner diameter of the lithium cylindrical body is used, it is easy to install this hollow rubber body inside the lithium cylindrical body, and it is easy to increase the internal pressure of this hollow rubber body. By this method, the lithium cylindrical body can be firmly attached to the metal container. Furthermore, since lithium does not adhere to the open end of the metal container, welding defects can also be prevented.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a lithium battery manufactured by the method of the present invention, and FIG. 2 is a diagram illustrating the steps of manufacturing a lithium battery by the method of the present invention. 1... Metal container, 2... Lithium negative electrode, 101
...Hollow rubber body, 103... Compressor.

Claims (1)

[Claims] 1. A lithium cylindrical body smaller than the container size is inserted into the inner surface of a metal container, a hollow rubber body is inserted inside the metal container, and the hollow rubber body is expanded and deformed by pressurizing the hollow part to form the lithium cylindrical shape. A method for manufacturing lithium batteries characterized by pressing the body onto the inner surface of a metal container.