JPH0433648Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to the improvement of a cylindrical injection tube that also serves as a terminal for a sealed battery. In addition to providing a notch for liquid injection, the cylindrical part located below the notch is pressed into a flat shape, and the lead wire or lead tab is welded and fixed to the same part to attach the lead wire. easily and reliably, eliminating defects during lead wire installation processing,
Another object of the present invention is to provide a battery with excellent vibration resistance and shock resistance.

In general, for batteries such as lithium batteries that can withstand long-term use and require complete sealing, all battery components such as the active material and electrolyte are housed in a metal case, and the metal case is welded all around. It has a completely sealed structure.

In such batteries, the metal case also serves as one terminal, and the terminals with the other polarity are usually hermetically sealed from the metal case with glass or ceramic to maintain insulation and airtightness. In batteries where liquid is poured last after all the batteries are assembled, the terminal, which has a polarity different from that of the metal case, is often cylindrical and also serves as the liquid injection pipe. That is, after placing the electrode plate group in a state in which liquid has not been injected into a metal case and welding the peripheral part of the metal case, as described above, the electrode plate group is inserted into the battery from a cylindrical liquid injection pipe that also serves as a terminal provided in a part of the metal case. A method is adopted in which the electrolytic solution is injected by a vacuum injection method or the like, and then the tip of the injection tube is heated and melted to seal it.

In this case, in order to prevent the airtightness between the injection tube and the metal case from deteriorating due to the heat generated when the tip of the injection tube is melted and sealed, the airtight seal should be made of glass or ceramic, which has high heat resistance and mechanical strength. A hermetic seal is essential. In addition, it is necessary to electrically connect the electrode plate and the liquid injection tube inside the battery before welding the peripheral part of the metal case, and in the past, the lead wire or lead tab from the electrode plate was connected to the side of the liquid injection tube. A commonly used method was to integrate the two by spot welding. This work involves spot welding the lead wire onto a curved surface, which is a difficult operation, so welding strength varies depending on how the electrode of the spot welding machine is applied, and in severe cases, sparks may be generated during welding and part of the lead wire may be damaged. Simply melting caused problems such as welding defects. In addition, due to welding variations, spot welds came off when vibrations or shocks were applied, resulting in problems such as unusability.

The present invention eliminates these problems and provides a liquid injection pipe that allows lead wires to be attached easily and reliably.As a result, defects during battery manufacturing can be reduced and batteries with excellent vibration and shock resistance can be produced. This is what we provide.

Examples will be described below with reference to the accompanying drawings.

FIG. 1 is a longitudinal sectional view of a sealed thionyl chloride/lithium battery using a liquid injection tube according to the present invention, and FIG. 2 is a partially enlarged view of the liquid injection tube. In FIGS. 1 and 2, 1 is a stainless steel case that also serves as a negative electrode terminal, on the inner surface of which lithium 2 is crimped and fixed, a glass non-woven fabric separator 3 and a bottom insulator 4.
Positive electrode current collector 5 made of acetylene black
and nickel expanded metal grid 6
is insulated and isolated. Reference numeral 7 denotes a stainless steel cover, which is integrally welded to the stainless steel case 1 at its periphery. SUH 446 which also serves as positive terminal
The liquid injection tube 8 consists of a glass hermetic seal 9.
It is insulated from the stainless steel cover 7 and kept airtight, and has a notch 10 that serves as a liquid injection hole at a location located inside the battery, and is made by pressing the part below this part in advance. flat surface 1
4, nickel expanded metal grid 6
Nickel lead tab 11 integrated with
are spot welded. This was installed before the stainless steel case 1 and stainless steel cover 7 were assembled during battery assembly. Thionyl chloride, which is a positive electrode active material that also serves as an electrolyte, is injected under reduced pressure from the injection pipe after welding the stainless steel case 1 and the stainless steel cover 7 together.
It flows into the battery through the notch 10 and is held in the central space 12 of the expanded metal grid 6, the positive electrode current collector 5, and the glass separator 3. The tip 13 of the liquid injection tube 8 is welded and sealed after thionyl chloride is injected, making the battery completely sealed.

As described above, the battery having the structure based on the present invention has a notch 10 for liquid injection on the side surface of the liquid injection tube 8 located inside the battery, and a lead tab 11 for spot welding which is made flat by pressing or the like. It is characterized by having a flat end surface 14, and because the lead tab is attached to the liquid injection tube by spot welding to the flat surface, there is no defect at all during attachment, and it is extremely easy to install. Strongly integrated. Therefore, even when vibrations or shocks are applied, the lead tabs will not come off at the same location and will not become unusable.

Although spot welding of the lead tab to the liquid injection pipe has been described here, the present invention is not limited to the lead tab, and the same effect can be obtained with the lead wire.

In addition, although we have described a thionyl chloride/lithium battery as a representative example of a sealed battery, it is not necessarily limited to this type of battery; after the battery is assembled, the electrolyte is finally injected, and then the injection tube is sealed. It is clear that this is common to any type of sealed battery that is completely sealed.

As detailed above, the present invention eliminates defects during battery manufacturing and provides a battery with excellent vibration resistance and shock resistance, and has great practical value.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a sealed thionyl chloride/lithium battery according to the present invention, and FIG. 2 is an enlarged view of the injection pipe of the battery shown in FIG. 1...Stainless steel case, 7...Stainless steel cover, 8...Positive terminal that also serves as a liquid injection pipe, 9...
...Glass hermetic seal, 10...Notch,
11...Nickel lead tab, 14...Flat surface.

Claims (1)

[Scope of claim for utility model registration] One terminal 8 that also serves as a liquid injection pipe has a metal cover 7
The metal cover 7 closes the metal case 1 which also serves as the other terminal, and the terminal 8 which also serves as the liquid injection pipe is located inside the battery. A notch 10 for liquid injection is provided on the side surface, and a flat surface 14 is provided below the notch 10 of the terminal 8, which also serves as the liquid injection pipe, so that a lead wire or lead tab 11 can be inserted. The flat surface 1
4, and the upper end of the terminal 8, which also serves as the liquid injection pipe, located on the outside of the battery, is sealed 13.