JPH08298110A - Electrolyte injection method and device - Google Patents

Abstract

(57) [Summary] [Purpose] To easily inject the electrolyte into the battery can container. [Structure] A storage cup 41 for storing the electrolytic solution 12 is provided in a vacuum chamber 31. This reservoir cup 41 has an open / close valve
The liquid injection nozzle 47 is connected via 45. A pad 51 made of an elastic body is provided at the tip of the liquid injection nozzle 47. Storage cup
A carrier 53 for holding the battery can container 2 is provided below the 41. With the on-off valve 45 closed, the inside of the vacuum chamber 31 is decompressed, the air inside the battery can container 2 is removed, and the electrolytic solution 12 is defoamed. After that, the carrier 53 is raised and the periphery of the injection hole 7a of the battery can container 2 is brought into contact with the pad 51. After this,
The atmosphere in the vacuum chamber 31 is gradually increased. Then
A pressure difference is generated between the inside and outside of the battery can container 2, and the pad 51 is brought into close contact with the battery can container 2 due to this pressure difference. The on-off valve 45 is opened during this boosting operation. Then, the battery can container 2
Due to the pressure difference between the inside and the outside, the electrolyte solution 12 in the storage cup 41 enters the inside of the battery can container 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrolytic solution injecting method and an electrolytic solution injecting apparatus for injecting an electrolytic solution into a battery container.

[0002]

2. Description of the Related Art Conventionally, for example, a lithium secondary battery 1 shown in FIGS. 9 and 10 is known. The lithium secondary battery 1 mainly includes a battery can container 2, an electrode body 3 housed in the battery can container 2, an electrode cover 4, an insulating member 5,
And an electrolyte that produces an electromotive force. The battery can container 2 is composed of an outer can 6 and a cap body 7 having an injection hole 7a for injecting an electrolytic solution. The electrode body 3 has tab terminals for the positive electrode and the negative electrode. Further, the electrode cover 4 enhances electrical continuity between the electrode body 3 and the outer can 6, and the insulating member 5 insulates the cap body 7 and the electrode body 3 from each other.

Then, in such a lithium secondary battery 1, in order to improve the quality of the battery, the electrolytic solution is placed in a gap between the positive electrode constituent material and the negative electrode constituent material in a unit of micrometer. It is desirable to impregnate it uniformly.

However, since the electrolytic solution has a high viscosity, and the electrode constituent members inside the battery can container 2 are formed in a dense coil shape in terms of battery performance, it is not easy to inject the electrolytic solution through the injection hole 7a. Absent.

In this respect, conventionally, the injection method using the injection device shown in FIG. 11 has been adopted.

This injection device is provided with a storage cup 11, and a predetermined amount of the electrolytic solution 12 is stored in the storage cup 11. Also, an opening is provided on the upper side of the storage cup 11.
11a is provided, and a predetermined amount of electrolytic solution 12 is supplied to the opening 11a from a supply pipe 13 of a metering pump (not shown). Further, an upper lid 14 that can move up and down is provided so as to face the opening 11a. The upper lid 14 is in close contact with the opening 11a to cover the opening 11a in an airtight manner, and is connected to a vacuum device (not shown) to evacuate the inside of the storage cup 11. On the other hand, a liquid injection nozzle unit 16 is provided below the storage cup 11. The liquid injection nozzle unit 16 is provided with an electrolytic solution passage hole 17 communicating with the inside of the storage cup 11, and a seal member 18 provided at a lower end portion of the electrolytic solution passage hole 17. Further, the storage cup 11 and the liquid injection nozzle unit 16 are driven to move up and down by a drive device 19.

In the pouring device having such a structure, first, the liquid pouring nozzle unit 16 is lowered and brought into contact with the cap body 7 of the battery can container 2 arranged below the storage cup 11. Then, after a predetermined amount of the electrolytic solution 12 is supplied into the storage cup 11 by the metering pump, the upper lid 14 connected to the vacuum device is lowered to be brought into close contact with the storage cup 11. In this state, when the vacuum device is operated to evacuate the inside of the storage cup 11, the inside of the battery can container 2 is evacuated through the storage cup 11 and the electrolyte passage hole 17 of the liquid injection nozzle unit 16.
The electrolyte solution 12 in the storage cup 11 is injected into the battery can container 2, and the air in the battery can container 2 is removed and the storage cup 11 is stored.
The gas contained in the electrolytic solution 12 inside is defoamed.
Then, after a predetermined time has passed in this state, the upper lid 14 and the liquid injection nozzle unit 16 are raised to complete the liquid injection operation.

However, in the method using this injection device, when the electrolytic solution 12 is injected into the battery can container 2, the air in the battery can container 2 and the gas such as nitrogen contained in the electrolytic solution 12 itself are injected. It is necessary to evacuate through the electrolytic solution 12, and there is a problem that injection takes a long time. Further, since the seal member 18 of the liquid injection nozzle unit 16 is mechanically pressed and closely adheres to the periphery of the injection hole 7a of the cap body 7 of the battery can container 2, the sealing property is low, and the leakage of the electrolyte solution 12 or the like occurs. Therefore, there is a problem that the injection amount of the electrolytic solution 12 varies or the electrolytic solution 12 adheres to the outer surface of the battery can container 2.

[0009]

As described above, in the injection method using the conventional injection device, it takes a long time to inject the electrolytic solution 12, and the electrolytic solution 12 leaks to cause the electrolytic solution to leak.
There is a problem that the injection amount of 12 fluctuates or the electrolytic solution adheres to the outer surface of the battery can container 2.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an electrolytic solution injecting method and an apparatus therefor capable of easily injecting an electrolytic solution into a battery container.

[0011]

According to a first aspect of the present invention, there is provided a method of injecting an electrolytic solution, wherein the electrolytic solution stored in the battery container and the storage means is evacuated in the same vacuum system, respectively, and the battery container and the storage device. And a step of connecting the means and a step of boosting the pressure of the vacuum system and injecting the electrolytic solution from the storage means into the battery container.

According to a second aspect of the present invention, there is provided an electrolytic solution injecting method according to the first aspect, wherein in the step of connecting the battery container and the storage means, a pad made of an elastic body that can be brought into contact with and separated from the battery container. The battery container and the storage means are connected to each other by using a liquid injection nozzle provided with.

According to another aspect of the present invention, there is provided an electrolytic solution injecting device, which comprises a storage means for storing an electrolytic solution, a liquid injection nozzle provided with a pad made of an elastic body which is connected to the storage means and which can be brought into and out of contact with a battery container. A vacuum chamber for accommodating the storage means and the battery container, and an exhaust means for evacuating the inside of the vacuum chamber are provided.

[0014]

In the present invention, the electrolytic solution stored in the battery container and the storage means is evacuated in the same vacuum system, so that the battery container is evacuated and the electrolytic solution stored in the storage means is defoamed effectively. To be done. Then, while the battery container and the storage means are connected to each other, the pressure in the vacuum system is increased to utilize the pressure difference between the inside and the outside of the battery container to easily inject the electrolytic solution into the battery container from the storage means. It

[0015]

EXAMPLE An example of the electrolytic solution injecting method and the electrolytic solution injecting apparatus of the present invention will be described below with reference to the drawings regarding the electrolytic solution injection in the manufacturing process of a rectangular lithium secondary battery. The lithium secondary battery will be described with the same reference numerals as in the conventional example.

In FIG. 1, reference numeral 31 denotes a vacuum chamber, which is connected to a vacuum device such as a vacuum pump (not shown) as an evacuation means via a flow passage pipe 32, and the inner portion has an atmospheric pressure and a vacuum. It is designed to be converted to and from a pressure atmosphere. Further, the vacuum chamber 31 is formed with upper and lower openings 33 and 34, which are hermetically closed by an upper lid 35 and a lower lid 36, respectively.

A storage cup 41 serving as a storage means is provided in the vacuum chamber 31, and a predetermined amount of the electrolytic solution 12 is stored in the storage cup 41.

On the upper side of the vacuum chamber 31, a supply pipe 42 connected to a metering pump for supplying a predetermined amount of electrolytic solution is arranged so as to be able to move forward and backward. The supply pipe 42 is located above the storage cup 41 in a state where the upper lid 35 is opened, supplies a predetermined amount of the electrolytic solution 12 to the storage cup 41, and when the upper lid 35 is closed, the It is designed to be evacuated to people.

An electrolytic solution passage hole 44 is provided in the lower portion of the storage cup 41, and the electrolytic solution passage hole 44 is formed.
An open / close valve 45 having a two-way valve structure for temporarily closing the outflow of the electrolytic solution 12 is connected to the. And this on-off valve 45
The electrolyte discharge hole 48 of the liquid injection nozzle 47 is connected to the lower side of the liquid injection nozzle 47, and a pad 51 is provided at the tip of the liquid injection nozzle 47.
Is provided. The pad 51 is formed of an elastic body into an annular shape that spreads downwards.
A hole portion (not shown) communicating with the electrolyte discharge hole 48 of 47 is formed.

Further, on the upper side of the lower lid 36, there is provided a carrier 53 for holding, fixing and transferring a battery can container 2 as a battery container accommodating the electrode body 3 and the like at a predetermined position. A lifter mechanism (not shown) for raising and lowering 53 is provided.

Next, the operation of the electrolytic solution injecting apparatus of this embodiment will be described.

First, as shown in FIG. 1, the vacuum chamber 31
With the upper lid 35 and the lower lid 36 open and the open / close valve 45 closed, the carrier is placed at a predetermined position under the vacuum chamber 31.
While transferring and setting the battery can container 2 stored in 53,
A predetermined amount of the electrolytic solution 12 is supplied into the storage cup 41 from a supply pipe 42 of a metering pump. Then, after supplying the electrolytic solution 12 to the storage cup 41, the supply pipe 42 is retracted laterally.

Subsequently, as shown in FIG. 2, a vacuum chamber
In a state in which the upper lid 35 and the lower lid 36 of 31 are driven and closed, respectively, and the storage cup 41 and the battery can container 2 are housed inside,
The vacuum chamber 31 is closed. In this state, with the open / close valve 45 closed, the vacuum pump is operated to perform vacuuming to reduce the atmosphere in the vacuum chamber 31. In this state, the battery can container 2, the opening / closing valve 45, and the liquid injection nozzle
The air removal inside 47 and the defoaming of the gas contained in the electrolytic solution 12 in the storage cup 41, such as air and nitrogen, are individually performed in the same vacuum system.

Next, as shown in FIG. 3, the lifter mechanism (not shown) raises the carrier 53 so that the injection hole 7a of the cap body 7 of the battery can container 2 communicates with the electrolyte discharge hole 48 of the injection nozzle 47. At the same time, the periphery of the injection hole 7a is brought into contact with the pad 51 at the tip of the liquid injection nozzle 47.

After this, as shown in FIG. 4, so-called slow leak is performed to gradually increase the atmosphere in the vacuum chamber 31 relatively to the atmospheric pressure. Then, a pressure difference is generated between the inside and the outside of the battery can container 2 and the electrolyte discharge hole 48, and the pressure difference causes the pad 51 made of an elastic body to elastically deform and adhere to the battery can container 2.

During this boosting operation, the open / close valve 45 is opened as shown in FIG. Then, due to the pressure difference between the internal pressure of the battery can container 2 and the atmospheric pressure in the vacuum chamber 31, the electrolyte solution 12 in the storage cup 41 is inevitably in contact with the electrolyte solution passage hole 44, the electrolyte solution discharge hole 48, and the electrolyte solution discharge hole 48. It is injected into the battery can container 2 through the injection hole 7a. At this time, the pressure increase in the vacuum chamber 31 is continued up to the atmospheric pressure state.

Then, after completing the injection operation, as shown in FIG.
As shown in FIG. 5, a predetermined operation is performed to uniformly impregnate the electrolytic solution 12 injected into the battery can container 2 between the positive electrode member and the negative electrode member inside the battery can container 2.

After completion of each of the above-mentioned operations, as shown in FIG. 7, the carrier 53 is lowered by the lifter mechanism to separate the battery can container 2 from the liquid injection nozzle 47, and thereafter, as shown in FIG. As shown, the upper lid 35 and the lower lid 36 of the vacuum chamber 31.
And the open / close valve 45 is opened.

Then, from this state, the carrier 53 accommodating the battery can container 2 is transferred from the vacuum chamber 31 to the outside, and the injection operation of the electrolytic solution 12 is completed.

As described above, according to this embodiment, when the electrolytic solution is injected in the manufacturing process of the prismatic lithium secondary battery 1, the electrolytic solution 12 stored in the battery can container 2 and the storage cup 41 is used.
By evacuating and in the same vacuum chamber 31, respectively, the battery can container 2 can be evacuated and the electrolyte solution 12 can be degassed efficiently and effectively, and the electrolyte solution 12 can be easily removed. It becomes possible to inject it into the container 2 and the electrolytic solution
The injection time of 12 can be shortened.

Then, the injection hole 7a of the cap body 7 of the battery can container 2 and the storage cup 41 are placed in a vacuum atmosphere and
With the open / close valve 45 closed, connection is made via the electrolyte discharge hole 48 of the liquid injection nozzle 47, then the pressure in the vacuum chamber 31 is increased, and the open / close valve 45 is opened to open the battery can container 2
The electrolytic solution 12 can be easily injected from the storage cup 41 into the battery can container 2 by utilizing the pressure difference between the inside and the outside of the battery, and the injection time of the electrolytic solution 12 can be shortened.

Further, since the pad 51 made of an elastic material is provided at the tip of the liquid injection nozzle 47 and the opening / closing valve 45 that operates in the vacuum chamber 31 is provided, this pad 51 is used in a vacuum atmosphere for the battery can container 2 After contacting the periphery of the injection hole 7a of the cap body 7, the vacuum chamber 31 is slowly leaked, and the pressure inside the vacuum chamber 31 is relatively gradually increased, so that the inside and outside of the battery can container 2 are exposed. Pressure difference of
By utilizing this pressure difference, the degree of adhesion between the pad 51 and the battery can container 2 can be increased. Therefore, the airtightness of the connection portion between the liquid injection nozzle 47 and the battery can container 2 is increased to prevent liquid leakage at the time of injecting the electrolytic solution 12, and the accuracy of the injection amount of the electrolytic solution 12 is increased, and the battery can container 2 is also provided. It is possible to prevent the electrolytic solution 12 from adhering to the outer surface of the.

Further, by the pad 51 made of an elastic body,
Since the pressure difference between the inside of the battery canister 2 and the ambient air can be maintained, it is possible to inject the electrolytic solution 12 in a state where the adhesion between the battery canister 2 and the pad 51 of the liquid injection nozzle 47 is improved. above,
Due to the above pressure difference, the electrolytic solution 12 can be efficiently injected into the battery can container 2, the fluctuation of the injected amount of the electrolytic solution 2 can be reduced, and the accuracy of the injected amount can be improved.
The injection time can be significantly reduced.

[0034]

According to the present invention, the electrolyte solution stored in the battery container and the storage means is evacuated in the same vacuum system to evacuate the battery container and release the electrolyte solution stored in the storage means. The foam can be effectively done.
Then, by boosting the pressure in the vacuum system with the battery container and the storage means connected, the electrolytic solution can be easily injected from the storage means into the battery container by utilizing the pressure difference between the inside and the outside of the battery container. It is possible to shorten the injection time of the electrolytic solution.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an embodiment of an electrolyte injection device of the present invention.

FIG. 2 is an explanatory diagram showing an injection operation of an electrolytic solution of the above.

FIG. 3 is an explanatory diagram showing an injection operation of the electrolytic solution, which is subsequent to FIG.

FIG. 4 is an explanatory diagram showing an injection operation of the electrolytic solution following that of FIG.

FIG. 5 is an explanatory diagram showing an injection operation of the electrolytic solution, which is subsequent to that of FIG.

FIG. 6 is an explanatory diagram showing an injection operation of the electrolytic solution, which is subsequent to FIG.

FIG. 7 is an explanatory view showing an injection operation of the electrolytic solution following that of FIG. 6;

FIG. 8 is an explanatory diagram showing an injection operation of the electrolytic solution following that of FIG. 7;

FIG. 9 is an explanatory diagram showing a configuration of a lithium battery.

FIG. 10 is an explanatory diagram of a lithium battery of the above.

FIG. 11 is an explanatory view showing a conventional injection device.

[Explanation of symbols]

 2 Battery can container as a battery container 12 Electrolyte solution 31 Vacuum chamber 41 Storage cup as a storage means 47 Injection nozzle 51 Pad

Claims (3)

[Claims] 1. A step of evacuating the electrolytic solution stored in a battery container and a storage means in the same vacuum system, a step of connecting the battery container and the storage means, and a step of boosting the vacuum system. And a step of injecting the electrolytic solution into the battery container from the storage means. 2. In the step of connecting the battery container and the storage means, the battery container and the storage means are connected by using a liquid injection nozzle equipped with a pad made of an elastic body that can be brought into contact with and separated from the battery container. The electrolytic solution injecting method according to claim 1, wherein 3. A storage means for storing an electrolytic solution, a liquid injection nozzle provided with a pad made of an elastic body, which is connected to the storage means and is capable of coming into contact with and separating from the battery container, and the storage means and the battery container. An electrolyte injection device comprising: a vacuum chamber; and an evacuation unit for evacuating the inside of the vacuum chamber.