KR20170019614A - Device for Electrolyte Injection Including Vacuum Generator and Battery Cell Prepared by Using the Same - Google Patents

Abstract

The present invention relates to a device for injecting an electrolyte into a battery case in which an electrode assembly is accommodated in a housing part in a process of manufacturing a battery cell. The present invention relates to an electrolyte injection device which includes an electrolyte injector mounted on one side of a battery case; and a vacuum generator spaced apart from the electrolyte injector on the one side of the battery case. The vacuum generator evacuates a storage part and then allows the electrolyte injector to inject the electrolyte into the storage part. So, it is possible to induce the electrolyte to be impregnated deeply into an electrode.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrolyte injection device including a vacuum generator and a battery cell using the same,

The present invention relates to an electrolyte injection apparatus including a vacuum generator and a battery cell manufactured using the same.

Due to the development of technology and demand for mobile devices, the demand for secondary batteries is also rapidly increasing. Among them, lithium secondary batteries, which have high energy density, high operating voltage and excellent storage and life characteristics, It is widely used as an energy source.

The lithium secondary battery has a structure in which an electrolyte solution containing a lithium salt is impregnated in an electrode assembly having a porous separator interposed between a positive electrode and a negative electrode coated with an active material on a current collector. The cathode active material is mainly composed of a lithium cobalt oxide, a lithium manganese oxide, a lithium nickel oxide, a lithium composite oxide and the like, and the anode active material is mainly composed of a carbon-based material. During charging, lithium ions of the positive electrode active material are released and inserted into the carbon layer of the negative electrode. In discharging, lithium ions of the negative electrode carbon layer are released and inserted into the positive electrode active material. At this time, the electrolyte moves lithium ions between the negative electrode and the positive electrode It acts as a medium to make.

Therefore, in order for the secondary battery including the above-mentioned electrode assemblies to have a high capacity and a high energy density and to maintain a long lifetime, the electrode assembly disposed inside the battery is completely impregnated with the electrolyte solution so that the electrode reaction between the electrodes can be actively performed When the electrode assembly is impregnated incompletely in the electrolyte solution, the reaction between the electrodes is not smooth, the resistance is increased, the output characteristics and the capacity of the battery are drastically lowered, thereby deteriorating the battery performance, shortening the life span, The battery is exposed to the risk of deterioration or explosion of the battery.

The electrolyte solution is introduced into the battery at the final stage of the production of the lithium secondary battery. In general, the electrolyte solution is a polar solvent having a polarity capable of effectively dissolving and dissociating the electrolyte salt, and is an aprotic solvent having no active hydrogen. These electrolytic solutions often have a high viscosity and surface tension due to extensive interactions within the electrolyte and are difficult to penetrate into an electrode assembly that is laminated at high density or wound in a laminated state and therefore requires a long time to impregnate the electrolyte .

Therefore, in order to improve the performance of the secondary battery and improve safety, various methods for increasing the electrolyte impregnability of the electrode assembly have been continuously studied.

FIG. 1 illustrates a process for impregnating an electrolyte in a conventional vacuum chamber.

1, an electrolytic solution is injected into a battery case 20 in which an electrode assembly (not shown) is incorporated in step (a), and a battery case 20 in which an electrolyte is injected in step (b) 30). The battery case 20, which has been moved into the vacuum chamber 30, is evacuated to remove gases inside the pores in the electrode assembly in a vacuum state and to induce the electrolyte to be impregnated deeply into the electrode assembly. In step (c), the outer circumferential surface of the battery case 20 emerging from the vacuum chamber 30 is sealed to complete the battery cell manufacturing process.

However, such a conventional liquid pouring method has a limitation in that the gas in the pores in the electrode is not completely removed since the battery cell moves to the vacuum chamber in the state where the electrolyte solution is poured therein, so that the electrolyte solution is impregnated into the electrode.

Therefore, there is a high need for a technique capable of improving electrolyte impregnability in a battery cell manufacturing process.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and the technical problems required from the past.

In particular, it is an object of the present invention to provide an electrolyte solution injecting apparatus capable of completely removing gas inside an electrode during a process of injecting an electrolyte solution into an electrode assembly in a battery cell manufacturing process to induce the electrolyte solution to be impregnated deeply into the electrode.

According to an aspect of the present invention,

An apparatus for injecting an electrolyte into a battery case in which an electrode assembly is housed in a housing part in a manufacturing process of the battery cell,

An electrolyte main liquor mounted on one side of the battery case; And

A vacuum generator mounted on a side of the battery case at a position spaced apart from the electrolyte main liquor;

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The electrolyte solution injecting apparatus may have a structure in which the accommodating section is made to be vacuumed by the vacuum generator, and then the electrolytic solution injector injects the electrolytic solution into the accommodating section.

Therefore, the electrolyte injection device according to the present invention can completely remove the gas in the electrode by making the accommodating portion vacuum by the vacuum generator, and by injecting the electrolytic solution into the electrode from which the gas is removed by the electrolyte injector, It can be induced to be deeply impregnated.

The electrode assembly may have a stacked or stacked / folded structure.

The battery case may be a pouch type case having a laminate structure including a metal layer and a resin layer.

As a specific example of the battery case, the battery case is made of a laminate sheet including a resin outer layer of excellent durability, a metal layer of barrier property, and a heat-fusible resin sealant layer, and the resin sealant layers are heat- .

Since the resin outer layer must have excellent resistance from the external environment, it is necessary to have a tensile strength and weather resistance higher than a predetermined level. In this respect, polyethylene terephthalate (PET) and stretched nylon film can be preferably used as the polymer resin of the outer resin layer.

The barrier metal layer may preferably be made of aluminum so as to exhibit a function of improving the strength of the battery case, in addition to a function of preventing foreign matter such as gas or moisture from leaking or leaking.

The resin sealant layer may preferably be a polyolefin resin having low heat absorbability (thermal adhesiveness), low hygroscopicity to suppress penetration of an electrolyte solution, and not being swollen or eroded by an electrolytic solution, Preferably, lead-free polypropylene (CPP) can be used.

The outer circumference of the battery case may be thermally fused and sealed except for a portion where the electrolyte liquid main body and the vacuum generator are mounted. This can be done to completely seal the inside of the storage portion except for the portion communicated with the electrolyte main liquor and the vacuum generator and to make the inside of the storage portion completely vacuumed by the vacuum generator.

As one specific example of the electrolyte injector,

An electrolyte inflow portion into which an electrolytic solution flows from the outside of the electrolyte solution instilling device and communicates with an upper portion of the electrolytic solution storing portion;

An electrolytic solution storage part for storing the electrolytic solution introduced from the electrolytic solution inflow part and communicating with the lower electrolytic solution injection part at the lower part; And

An electrolyte injecting unit mounted through one side of the battery case and injecting the electrolytic solution introduced from the electrolyte storage unit into the accommodating unit;

As shown in FIG.

In addition, a first valve may be mounted on the communicating portion of the electrolyte inflow portion and the electrolyte reservoir, and a third valve may be mounted on the communicating portion of the electrolyte reservoir and the electrolyte infusion portion.

According to the above structure, in the electrolyte solution injecting apparatus according to the present invention,

The first valve is opened in a state where the third valve is closed so that the electrolytic solution can flow into the electrolytic solution storing part from the electrolytic solution inflow part and the introduced electrolytic solution can be stored in the electrolytic solution storing part.

Then, the first valve is closed and the third valve is opened in a state where the storage portion is evacuated by the vacuum generator, so that the electrolyte solution can be injected into the storage portion from the electrolyte storage portion through the electrolyte injection portion.

In addition to the above structure, the vacuum generator may be equipped with a second valve at a portion in contact with the battery case.

Specifically, the second valve may be opened in a state in which the housing part is not opened, thereby making the interior of the housing part vacuum, and the second valve may be closed in a state where the housing part is evacuated. The electrolytic solution can be injected from the electrolyte injector into the storage portion in a state where the second valve is closed and the storage portion is evacuated.

After the electrolytic solution injecting process as described above, the battery case may be sealed with an electrolyte injected into the accommodating portion, and one side of the battery case may be thermally fused with the electrolytic liquid main body and the vacuum generator removed from the battery case. In order to prevent the gas from being reintroduced into the accommodating portion in a state where the electrolyte liquid main body and the vacuum generator are removed, the operation of removing the electrolyte liquid main body and the vacuum generator and sealing the battery case by heat fusion can be performed at the same time.

As an example of the electrolyte liquid main body and the vacuum generator, the electrolyte liquid main body and the vacuum generator may have a hose or pipe structure. The structures of the electrolyte main liquid and the vacuum generator can be changed according to the desired time of injecting the electrolyte solution. For example, in order to shorten the electrolyte injecting process, the cross-sectional area of the main liquid electrolyte and the vacuum generator can be increased. However, in such a case, there may arise a problem that the sealing portion is opened in the step of sealing the battery case after injecting the electrolyte solution . On the other hand, when the cross-sectional area of the main liquid electrolyte and the vacuum generator is made small, the time for injecting the electrolyte solution can be increased, but the problem of the sealing part being worn during the step of sealing the battery case after injecting the electrolyte can be prevented.

As one example of the material constituting the electrolyte main liquid device and the vacuum generator, the electrolyte main liquid device and the vacuum generator may be made of a polymer resin at a portion in contact with the battery case.

Specifically, the polymer resin may be made of the same material as the material forming the inner surface of the battery case, or may be made of a polymer having affinity with the material.

When the electrolyte liquid main body and the vacuum generator are made of a polymer resin, the battery case may be completely sealed by heat-sealing one side in a state where the electrolyte liquid main body and the vacuum generator are mounted, The portions of the electrolyte main liquid and the vacuum generator are cut off, and the battery cell pouring process can be completed.

In another embodiment of the present invention, the electrolyte solution injecting apparatus may further include a vacuum chamber in which the electrolyte solution main body, the vacuum generator, and the battery case are housed in the vacuum chamber and completely cut off from the outside air. Accordingly, since the electrolyte pouring process is performed with the electrolyte main liquor, the vacuum generator, and the battery case positioned inside the vacuum chamber in a vacuum state, the gas in the electrode of the electrode assembly can be completely removed.

The present invention also provides a battery cell manufactured using the electrolyte injection apparatus.

The battery cell may be of various types, and in particular, the electrode assembly of the anode / separator / cathode structure may be a prismatic or cylindrical battery cell embedded in a square or cylindrical metal can, or the electrode assembly may include a metal layer and a resin layer A pouch-shaped battery cell of a thin thickness and a low weight which is sealed in a battery case of a laminate sheet including the pouch type battery cell.

The configurations of the anode, the separator, and the cathode are not limited, and may include all the configurations disclosed in the prior art, and a detailed description thereof will be omitted herein.

Further, the present invention provides a device including the battery cell, wherein the device may be a small device such as, for example, a mobile phone, MPEG Audio Layer-3 (MP3), a tablet PC, or a smart pad, But is not limited to, a mid-sized device such as an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, or a power storage device.

As described above, the electrolyte injection device according to the present invention can completely remove the gas in the electrode by making the holding part vacuum by the vacuum generator, and by injecting the electrolyte solution into the electrode from which the gas is removed by the electrolyte injector, It is possible to induce the electrolyte to be impregnated deeply into the electrode.

In addition, when the battery cell is manufactured by using the electrolyte solution injecting apparatus, the electrolyte impregnability can be improved, so that battery performance such as output characteristics, life characteristics, and battery capacity of the battery cell can be improved.

1 is a schematic view of a process of impregnating an electrolyte in a conventional vacuum chamber;
2 is a schematic view of an electrolyte injection device according to one embodiment of the present invention;
3 is an enlarged view of the "A" portion of FIG.
4 is a schematic view showing a state in which the electrolyte solution injecting apparatus of FIG. 2 is detached from the battery case after injecting the electrolyte solution;
FIG. 5 is a schematic view showing a state in which an electrolyte solution injecting apparatus is detached from a battery case after electrolyte solution injection according to another embodiment of the present invention. FIG.

Hereinafter, the present invention will be described in detail with reference to the drawings. However, the present invention is not intended to be limited by the scope of the present invention.

FIG. 2 is a schematic view of an electrolyte injection device according to one embodiment of the present invention, and FIG. 3 is an enlarged view of a portion "A" of FIG.

Referring to FIGS. 2 and 3, the electrolyte injection apparatus 100 includes an electrolyte main liquid 110 and a vacuum generator 120.

The electrolyte main liquor 110 is mounted on the upper left side of the battery case 200 and the vacuum generator 120 is mounted on the right side of the upper side of the battery case 200 at a position spaced apart from the electrolyte main liquor 110 have. The electrolyte main liquor 110 and the vacuum generator 120 have a pipe structure.

The electrolyte solution injecting apparatus 100 further includes a vacuum chamber 140 for storing the electrolyte main liquor 110, the vacuum generator 120 and the battery case 200 therein to completely block the electrolyte solution from the outside air. Since the electrolyte pouring process is performed with the electrolyte main liquor 110 and the vacuum generator 120 and the battery case 200 placed inside the vacuum chamber 140 in a vacuum state, Can be removed more completely.

The electrolyte main liquor 110 is operated to vacuum the storage portion 210 by the vacuum generator 120 and then inject the electrolyte into the storage portion by the electrolyte injector 110.

The outer periphery of the battery case 200 is thermally fused and sealed except for the portion where the electrolyte main liquor 110 and the vacuum generator 120 are mounted in a state where the electrolyte main liquor 110 and the vacuum generator 120 are mounted have.

Specifically, the electrolyte injector 110 includes an electrolyte inflow portion 111, an electrolyte reservoir portion 112, and an electrolyte injection portion 113.

The electrolyte inflow part 111 flows the electrolyte solution from the outside of the electrolyte solution injection device 100 and communicates with the upper part of the electrolyte solution storage part 112.

The electrolyte storage part 112 stores the electrolyte inflowed from the electrolyte inflow part 111 and the lower part is in communication with the electrolyte injection part 113.

The electrolyte injection portion 113 is installed through the upper side of the battery case 200 and injects the electrolyte solution introduced from the electrolyte storage portion 112 into the storage portion 210.

A first valve 131 is attached to a communicating portion between the electrolyte inflow portion 111 and the electrolyte reservoir portion 112 and a third valve 131 is provided in a communicating portion between the electrolyte reservoir portion 112 and the electrolyte injection portion 113. [ And a second valve 132 is attached to a portion where the vacuum generator 120 and the battery case 200 are in contact with each other.

The first valve 131 is opened when the third valve 133 is closed and the electrolytic solution in the electrolyte storage part 112 flows from the electrolyte inflow part 111 and is closed again.

The electrolyte injection device 100 opens the second valve 132 in a state in which the first valve 131 and the third valve 133 are closed to make the storage part 210 in a vacuum state, The second valve 132 is closed.

The first valve 131 is closed and the third valve 133 is opened and the electrolyte solution is supplied from the electrolyte storage part 112 through the electrolyte injection part 113 to the storage part 210).

FIG. 4 is a schematic view showing a state in which the electrolyte solution injecting apparatus of FIG. 2 is detached from the battery case after injecting the electrolyte solution.

Referring to FIG. 4 together with FIG. 2, in the battery case 200, when the electrolyte is injected into the housing part 210 and the electrolyte main liquor 110 and the vacuum generator 120 are removed from the battery case 200 , The upper side is thermally fused and sealed, and the electrolyte pouring step is completed.

The remaining structure except for this structure is the same as the structure of the embodiment described with reference to FIG. 2 and FIG. 3, and thus detailed description thereof will be omitted.

FIG. 5 is a schematic view showing a state in which an electrolyte solution injecting apparatus is detached from a battery case after electrolyte solution injection according to another embodiment of the present invention. FIG.

5, the electrolyte main liquor 310 and the vacuum generator 320 have a hose structure, and the portions 311 and 312 contacting the battery case 200 are made of a polymer resin.

The battery case 200 is completely sealed by thermally fusing the upper side while the electrolyte main liquor 310 and the vacuum generator 320 are mounted and the electrolyte main liquor 310 is disposed along the upper side of the battery case 200, And the vacuum generator 320 are cut to complete the electrolyte pouring process.

Although the present invention has been described with reference to the accompanying drawings, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the scope of the present invention.

Claims (17)

An apparatus for injecting an electrolyte into a battery case in which an electrode assembly is housed in a housing part in a manufacturing process of the battery cell,
An electrolyte main liquor mounted on one side of the battery case; And
A vacuum generator mounted on a side of the battery case at a position spaced apart from the electrolyte main liquor;
And,
Wherein the vacuum generator operates to evacuate the accommodating portion to vacuum, and then injects the electrolytic solution into the accommodating portion by the injector of the electrolytic solution. The electrolyte solution injecting apparatus according to claim 1, wherein the electrode assembly has a stacked or stacked / folded structure. The electrolyte solution injecting apparatus according to claim 1, wherein the battery case is a pouch-shaped case having a laminate structure including a metal layer and a resin layer. 4. The electrolyte solution injecting apparatus according to claim 3, wherein the outer circumference of the battery case is sealed by heat fusion except for a portion where the electrolyte liquid main body and the vacuum generator are mounted. The apparatus according to claim 1,
An electrolyte inflow portion into which an electrolytic solution flows from the outside of the electrolyte solution instilling device and communicates with an upper portion of the electrolytic solution storing portion;
An electrolytic solution storage part for storing the electrolytic solution introduced from the electrolytic solution inflow part and communicating with the lower electrolytic solution injection part at the lower part; And
An electrolyte injecting unit mounted through one side of the battery case and injecting the electrolytic solution introduced from the electrolyte storage unit into the accommodating unit;
And an electrolytic solution supply unit that supplies the electrolytic solution to the electrolytic solution supply unit. The electrolytic solution injecting apparatus according to claim 5, wherein a first valve is mounted on a communicating portion between the electrolyte inflow portion and the electrolytic solution storing portion, and a third valve is mounted on a communicating portion between the electrolytic solution storing portion and the electrolytic solution injecting portion. . The method according to claim 6,
The first valve is opened in a state where the third valve is closed, and the electrolytic solution flows from the electrolyte inflow part to the electrolyte solution storage part to store the electrolyte solution in the electrolyte solution storage part;
Wherein the first valve is closed and the third valve is opened in a state where the storage portion is in a vacuum state so that the electrolyte solution is poured into the storage portion from the electrolyte storage portion through the electrolyte injection portion. The electrolyte injection device according to claim 1, wherein a second valve is attached to a portion of the vacuum generator in contact with the battery case. 2. The electrolyte solution injecting apparatus according to claim 1, wherein the second valve is opened in a state in which the accommodating portion is in a vacuum state, and is made into a vacuum inside the accommodating portion, and the accommodating portion is closed in a vacuum state. The electrolyte solution injecting apparatus according to claim 1, wherein the battery case is sealed with an electrolyte solution injected into the housing member, and one side of the electrolyte solution main body and the vacuum generator is thermally fused and sealed in a state in which the electrolyte solution main body and the vacuum generator are removed from the battery case. The electrolyte solution injecting apparatus according to claim 1, wherein the electrolyte main liquor and the vacuum generator have a hose or pipe structure. The electrolyte solution injecting apparatus according to claim 1, wherein the electrolyte main liquor and the vacuum generator are made of a polymer resin at a portion in contact with the battery case. The electrolyte solution injecting apparatus according to claim 12, wherein the polymer resin is made of the same polymer as the material forming the inner surface of the battery case or having an affinity for the material. The battery case according to claim 13, wherein the battery case is completely sealed by heat-sealing one side in a state in which the electrolyte liquid main body and the vacuum generator are mounted, and portions of the electrolyte main liquid and the vacuum generator are cut along one side of the battery case . The electrolyte solution injecting apparatus according to claim 1, wherein the electrolyte solution injecting apparatus further comprises a vacuum chamber for containing the electrolyte main liquor, the vacuum generator, and the battery case therein to completely block the electrolyte solution from the outside air. A battery cell manufactured using the electrolyte solution injecting apparatus according to any one of claims 1 to 15. A device comprising a battery cell according to claim 16.

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