JPS6050028B2 - thin battery - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thin battery called a coin type battery.

Generally, in batteries using an alkaline electrolyte such as caustic potash, various measures have been taken to improve leakage resistance, such as applying a sealant to the sealing part.

However, in recent years, the demand for thin batteries has been increasing due to the need for smaller and lighter batteries.
The structure is such that the anode can and the cathode terminal plate are fitted through a gasket that contacts the inner peripheral surface and inner bottom surface of the anode can, and there is sufficient protection against liquid leakage from the contact surface between this gasket and the anode can. Currently, no countermeasures have been found yet.
In the thin battery described above, this invention prevents leakage from the contact surface between the anode can and the gasket by filling a liquid packing into the gap formed by the difference in curvature between the inner surface of the rising base of the anode can and the gasket surface. It sufficiently prevents liquid. Hereinafter, a case where the present invention is applied to an alkaline electrolyte battery will be explained based on the drawings.

rl・゛ ▼ ＾Mazroropa, a, 1゛ru, to n-cut nanny μ like 1ma; ``There is one sword, 1 is the anode can, 2 is the cathode terminal plate.

FIG. 2 shows the main parts thereof, in which the anode can 1 and the cathode terminal plate 2 are fitted together via an annular gasket 3 that is in contact with the inner bottom surface 5 and the inner circumferential surface 6 of the anode can 1. FIG. A gap is formed between the rising base inner surface 7 of the anode can 1 and the gasket surface 8 due to the difference in curvature between the two, and a liquid packing 4 made of asphalt pitch, fatty polyamide, wax, bolybdenum, etc. is sealed in this gap. has been done. The gap between the inner surface of the anode can 1 and the gasket 5 is
The curvature of the rising part of the gasket 5 is O, 05R, and the curvature of the rising part of the gasket 5 is O, 3R. This gap cannot be formed where the gasket 5 is compressed because the clamping force is weak, and must be formed where the clamping force is small, that is, between the inner surface of the rising base of the anode can 1 and the gasket 5. On the cathode side inside the battery, there is a cathode agent 9 containing a cathode active material such as zinc amalgam.
On the anode side, an anode mixture 10 mainly composed of an anode active material such as silver oxide is stored.The cathode side and the anode side are made of vinylon/rayon mixed paper, etc. in contact with the cathode agent 9. They are separated by the absorber 11 and the separator 12 which is in contact with the anode mixture 10. The inner periphery 13 is made of synthetic resin such as vinyl chloride or polystyrene. It is a ring-shaped insulator that is inserted between the gasket 3 and the anode can 1, and its outer peripheral end is pressed between the inner peripheral end of the gasket 3 and the anode can 1.Most of the electrolyte such as caustic potash is on the cathode side. A portion of the liquid backing 4 is injected into the anode side.As a means for sealing the liquid backing 4 into the gap, since normal liquid backing has considerable viscosity, a predetermined amount of this is injected into the anode can 1 in advance when assembling the battery. The simplest method is to attach the battery to the inner surface 7 of the rising base and assemble the battery according to the general process order.

The table below shows the battery A of the present invention in which asphalt pitch is used as the liquid backing in the above configuration example, and the battery A in which no gap is formed between the inner surface of the rising base of the anode can and the gasket surface and the liquid backing is not used. 2 shows the results of a leakage resistance test with Battery B having a conventional configuration.

The values in the table are based on leakage from the contact surface between the anode can and gasket when 50 batteries each of Batteries A and B were left in an atmosphere with a temperature of 60'C1 and a relative humidity of 90% for 20 days. is the number of batteries. As is clear from the table above, in the battery of this invention, the liquid backing is sealed in the gap formed by the difference in curvature between the inner surface of the rising base of the anode can and the gasket surface. The electrolyte that leaks through the contact surface between the inner surface and the gasket is diffused in this gap and exits through the sealed liquid backing, so the progress of the electrolyte is slow, resulting in poor leakage resistance. It seems that it will be very good.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an example of the battery of the present invention, and FIG. 2 is an enlarged sectional view of the main parts thereof. 1... Anode can, 2... Cathode terminal plate, 3
... Gasket, 4 ... Liquid backing, 5 ... Inner bottom surface of anode can, 6 ... Inner peripheral surface of anode can, 7 ... ...Inner surface of the rising base of the anode can, 8... Gasket surface.

Claims (1)

[Claims] 1 In a thin battery in which a cathode terminal plate and an anode can are fitted through a gasket in contact with the inner bottom surface and inner peripheral surface of the anode can, a gap is formed by the difference in curvature between the inner surface of the rising base of the anode can and the gasket surface. This thin battery is characterized by having a liquid packing sealed in this gap.