JPH05325945A - Electrolyte injection method for battery - Google Patents

Abstract

PURPOSE:To realize good adhesiveness between a sealed body and an outer can and also shorten an injection time by injecting an electrolyte in a required amount under a prescribed pressure reducing condition of an unsealed battery and thereafter, letting the inside of the battery to be under a pressure reducing condition near an atmospheric pressure and then, injecting a remaining electrolyte. CONSTITUTION:An exhaust pipe 2b is connected to the side of a high vacuum tank 9a by a change-over solenoid valve 4c to create a first pressure reducing condition of high vacuum. Then, a valve piston 6 is moved to the left side as shown in the Figure so that the inside of a measuring cylinder 7 and the inside of the battery 1 are connected through the injection pipe 2c and the injection pipe 6b of a valve piston 6 to lower a measuring piston 7a to a required position and a part of electrolyte is injected into the inside of the battery 1. Then, a solenoid valve 7a is opened and at the same time, the change-over solenoid valve 4 is changed over to connect the exhaust pipe 2b to the side of a low vacuum tank 9b so that a second pressure reducing condition of low vacuum is created inside the battery 1. Then, the solenoid valve 7a is again closed to keep the inside of the battery 1 in a pressure reducing condition and at the same time, the piston 7a is lowered to the original position and the remaining electrolyte is injected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for injecting an electrolytic solution for a battery, which is suitable for injecting an electrolytic solution into a dry battery having poor permeability.

[0002]

2. Description of the Related Art There are two known conventional simple methods for injecting an electrolytic solution into a battery case during the manufacturing process of a dry battery or the like.

One of the methods is a method in which the electrolytic solution is simply dropped from the upper part of the opening of the battery through the liquid supply pipe and penetrated into the battery element. Another method is to insert a liquid supply pipe into the inside of the battery and inject the liquid in order to increase the injection speed.

However, since these methods are carried out under normal pressure, it takes a lot of time to inject them into a dry battery or the like, which has poor permeability to the electrolytic solution, and improvement in productivity cannot be expected. Therefore, for the purpose of accelerating the injection speed, the inventors of the present application have proposed a battery electrolyte injection device as shown in FIG.

In FIG. 1, the opening of the unsealed battery 1 is brought into close contact with the sealing elastic member 2a of the holding mechanism 2, and then the vacuum pump 3 is inserted into the battery 1 through the solenoid valves 4a and 4b via the exhaust pipe 2b. Remove the air from and reduce the pressure. When the pressure reduction is completed, the solenoid valve 4a is closed to maintain the reduced pressure state in the battery 1.

In parallel with this depressurizing operation, the electrolytic solution tank 5
The electrolytic solution stored therein and sent via the liquid supply pipe 6a of the valve piston 6 is collected in the measuring cylinder 7 by raising the measuring piston 7a of the measuring cylinder 7.

After the depressurization and sampling operations are completed,
The valve piston 6 is moved to the left side in the drawing to connect the inside of the measuring cylinder 7 and the inside of the battery 1 through the liquid injection pipe 2c of the holding mechanism 2 and the liquid injection pipe 6b of the valve piston 6.

By this connecting operation, the electrolytic solution collected in the measuring cylinder 7 is injected into the battery 1 in a short time due to the suction action due to the pressure reduction in the battery 1 and the returning operation of the measuring piston 7a.

When the injection of the electrolytic solution into the battery 1 is completed, the release valve 8 is opened by the electromagnetic valve 4b to return the inside of the battery 1 to the normal pressure,
The battery 1 is separated from the holding mechanism 2 to complete the electrolyte injection operation for one battery. With such an apparatus, it has become possible to greatly improve the efficiency of the process of injecting the electrolytic solution.

[0010]

Although it has become possible to accelerate the work of injecting the electrolytic solution with the above-described electrolytic solution injecting device for a battery, such a decompression method has not yet completed the injection of the electrolytic solution. It can be seen that the inner wall of the opening of the battery at the sealing end gets wet with the electrolytic solution. As a cause of this phenomenon, it is considered that the electrolytic solution injected into the battery propagates up the inner wall of the battery due to the depressurizing action in the battery.

If the inner wall of the opening gets wet with the electrolytic solution for such a reason, the sealing body and the outer tube cannot be sufficiently adhered to each other when the battery is sealed, which causes deterioration of liquid leakage resistance.

The present invention has been made in order to solve such a problem, and injects an electrolyte solution for a battery, which can prevent the opening portion of the battery from being wet with the electrolyte solution without impairing the working speed of the electrolyte solution injection. It is intended to provide a way.

[0013]

The method for injecting an electrolytic solution for a battery according to the present invention is such that after the inside of an unsealed battery is brought into a first depressurized state, a required amount of the electrolytic solution is injected into the battery in the depressurized state. After injecting the required amount of the above, after the injection is completed, the inside of the battery is brought to a second depressurized state closer to normal pressure than the pressure of the first depressurized state, and the remaining electrolytic solution is put in the battery in this depressurized state. It is characterized by injecting.

[0014]

[Function] In this way, in the first depressurized state with a high degree of vacuum,
Injecting an amount of electrolytic solution that does not wet the inner wall of the battery opening, and then injecting the remaining electrolytic solution in a second depressurized state with a low degree of vacuum close to normal pressure, so without impairing the injection rate, It is possible to prevent wetting of the inner wall of the opening, which has been a cause of deteriorating liquid leakage resistance.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a flow chart for explaining the method of this embodiment, and FIG. 2 is a modification of the depressurization mechanism portion of the battery electrolyte injection device shown in FIG. 3 as one means for realizing the method of this embodiment. It is a block block diagram of a pressure reduction mechanism part.

In FIG. 2, the high vacuum tank 9a and the low vacuum tank 9b are connected to the vacuum pump 3 via pressure reducing control valves 10a and 10b, respectively.
The depressurizing action of the vacuum pump 3 is adjusted by a and 10b to maintain a required degree of vacuum.

These high vacuum tank 9a and low vacuum tank 9
b is selectively switched by the switching solenoid valve 4c. The exhaust output switched by the switching solenoid valve 4c is the solenoid valve 4a, 4b.
Through the exhaust pipe 2b shown in FIG. That is, the battery 1 is switched by switching the switching solenoid valve 4c.
The inside can be depressurized in two stages of high vacuum and low vacuum. With the battery electrolyte injection apparatus shown in FIGS. 2 and 3 configured as described above, the electrolyte injection method of this embodiment will be described with reference to FIG.
The flowchart will be described.

At step P1 of the flow chart of FIG.
The exhaust pipe 2b is connected to the high vacuum tank 9a side by the replacement solenoid valve 4c to bring the inside of the battery 1 into the high vacuum first depressurized state.
In Step P2, the electromagnetic valve 4a is closed after a predetermined time, and the inside of the battery 1 is maintained in the high vacuum first depressurized state. In parallel with these steps P1 and P2, in step P3, the required amount of the electrolytic solution in the electrolytic solution tank 5 is collected in the measuring cylinder 7.

In the next step P4, the valve piston 6 is moved to the left side in the drawing to connect the inside of the measuring cylinder 7 and the inside of the battery 1 through the liquid injection pipe 2c of the holding mechanism 2 and the liquid injection pipe 6b of the valve piston 6. , The metering piston 7a is lowered to a required position, and a first injection for injecting a part of the electrolytic solution into the battery 1 is performed.

After the first injection, the next step P5
Then, the solenoid valve 7a is opened, and the switching solenoid valve 4c is switched to connect the exhaust pipe 2b to the low vacuum tank 9b side.
The inside is brought to a second reduced pressure state of low vacuum.

In step P6, the solenoid valve 7a is closed again to maintain the inside of the battery 1 in the second depressurized state, and the measuring piston 7a is lowered to its original position to remove the remaining electrolytic solution from the battery 1.
Inject into. In step P7, the opening valve 8 is opened by the solenoid valve 7b to return the inside of the battery 2 to the normal pressure and the injection is completed.
After that, the battery 2 is separated from the holding mechanism 2, and the electrolyte injection operation for one battery is completed.

That is, according to the method of injecting the electrolytic solution of this embodiment, the electrolytic solution is injected in an amount that does not wet the inner wall of the battery 1 in the first depressurized state of high vacuum, and then the second method of low vacuum is applied. The method is to inject the remaining electrolyte under reduced pressure.
The present invention is not limited to the above-mentioned embodiments, and can be modified and carried out without changing the gist.

Although the apparatus as described in the above embodiment is used to realize the method for injecting the electrolytic solution of the present invention, the apparatus is not limited to the construction of the apparatus for carrying out the method of the present invention.

[0024]

According to the injection method of the present invention, since the inner wall of the opening of the unsealed battery does not get wet with the electrolytic solution, the cause of deterioration of the leakage resistance can be eliminated, and the sealing body can hit the sealing body. Sufficient adhesion is obtained between the outer can and the outer can. Further, according to the injection method of the present invention, the injection time can be greatly shortened as compared with the method of injecting the electrolytic solution under normal pressure.

[Brief description of drawings]

FIG. 1 is a flowchart illustrating an injection method according to an embodiment of the present invention.

FIG. 2 is a block configuration diagram of a decompression mechanism of the injection device used in the embodiment.

FIG. 3 is a block configuration and a partial cross-sectional view for explaining the configuration and operation of an injection device used in the same embodiment and a conventional injection method.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Battery, 2 ... Holding mechanism, 2a ... Sealing elastic member, 2b
... Exhaust pipe, 2c ... Liquid injection pipe 3 ... Vacuum pump, 4a, 4b ... Electromagnetic valve, 4c ... Switching solenoid valve, 5 ... Electrolyte tank, 6 ... Valve piston, 6a ... Liquid supply pipe, 6b ... Liquid injection pipe, Reference numeral 7 ... Metering cylinder, 7a ... Metering piston, open valve, 9a ... High vacuum tank, 9b ... Low vacuum tank, 10a, 10b ... Pressure reducing control valve.

Claims (1)

[Claims] 1. A first depressurized state is applied to the inside of an unsealed battery,
A required amount of the required injection amount of the electrolytic solution is injected into the battery in the reduced pressure state, and after the injection is completed, the inside of the battery is in a second reduced pressure state closer to normal pressure than the first reduced pressure. And injecting the remaining electrolytic solution into the battery in the depressurized state.