KR20200144269A - Device and Method for Testing Characteristics of Electrode - Google Patents

Abstract

The present invention relates to an electrode test apparatus comprising a three-electrode battery cell equipped with a positive electrode, a negative electrode, and a reference electrode, and to an electrode property test method using the same. When using the apparatus of the present invention, the solution resistance and thus the decrease in reproducibility, problems in the electrode properties in the conventional three-electrode cell, are greatly improved. In addition, unlike the conventional three-electrode cell to be manufactured in a glove box, it can be manufactured simply in a dry room, and it is possible to shorten the manufacturing time of the apparatus conventionally taking 1 to 2 days to within 1 hour, significantly shorter than that.

Description

Electrode test device and electrode characteristic test method using the same {Device and Method for Testing Characteristics of Electrode}

The present invention relates to an apparatus for testing electrode characteristics for a secondary battery and an electrode test method using the same.

As energy prices of fossil fuels rise and interest in environmental pollution increases, the demand for eco-friendly alternative energy sources is becoming an indispensable factor for future life. In particular, as technology development and demand for mobile devices increase. Accordingly, the demand for secondary batteries as an energy source is rapidly increasing.

Typically, in terms of the shape of the battery, there is a high demand for prismatic secondary batteries and pouch-type secondary batteries that can be applied to products such as mobile phones with a thin thickness. In terms of materials, lithium-ion batteries with high energy density, discharge voltage, and output stability, There is high demand for lithium secondary batteries such as lithium ion polymer batteries.

Recently, a pouch-type battery having a structure in which a stack-type or stack/folding-type electrode assembly is embedded in a pouch-type battery case of an aluminum laminate sheet has attracted a lot of attention due to low manufacturing cost, low weight, and easy shape transformation. Is also gradually increasing.

The pouch-type battery cell accommodates a stack-type or stack-folding electrode assembly manufactured by stacking a positive electrode, a separator, and a negative electrode. Each of the positive and negative electrodes is electrically connected by electrode tabs, and electrode leads drawn out to the outside are connected to the electrode tabs.

The electrode assembly to which the electrode tab and the electrode lead are connected is accommodated in a pouch-shaped battery case, and then an electrolyte is injected. A pouch-type battery cell is manufactured by sealing the battery case while a part of the electrode lead is exposed to the outside.

On the other hand, the battery case of the pouch-type battery cell is formed in a pouch shape to facilitate processing, so that there are few restrictions according to the size or shape of the electrode assembly, and the space inside the battery cell can be efficiently used. Accordingly, the pouch-type battery cell has high energy density and can be processed in various forms, and has recently been used in automobile batteries in various forms.

Meanwhile, in order to develop a new battery cell and check the performance of the manufactured battery cell, the potential, output, and capacity of the electrode are measured. This may be performed in the electrode development stage, or may be performed for quality discrimination of mass-produced electrodes.

In general, the performance test of an electrode is performed using a coin cell that combines a pure lithium electrode and an electrode that is the object of the characteristic measurement, which enables accurate characteristic measurement because all characteristics such as electrode potential or electrode resistance are already known. After manufacturing, it is repeatedly charged and discharged, and the life characteristics, output characteristics, and capacity characteristics of the electrode are measured.

In this way, the electrode potential of the battery is measured in order to develop a new battery cell and check the performance of the manufactured battery cell. In measuring the electrode potential, a three-electrode electrode potential measurement method consisting of a reference electrode, a working electrode and a potential electrode is mainly used.

The reference electrode is an electrode used to make a battery circuit for measuring electrode potential by combining it with the electrode to measure the potential of an electrode constituting a battery or an electrode in which electrolysis is taking place. When measuring the relative value of the electrode potential, the potential It becomes the standard of

When such a reference electrode is applied to a pouch type lithium secondary battery, in general, a reference electrode is inserted between a positive electrode and a negative electrode during the cell assembly process. In this case, since it has to be produced at the beginning of the experiment, it is difficult to measure the fresh cell that has progressed in the charge/discharge cycle, and it is difficult to use Li@Cu (LTO/Cu). Therefore, it is necessary to produce high quality and the manufacturing method is difficult. have.

Another conventional three-electrode cell measurement method to solve this disadvantage is to use a Li@Ni reference electrode and place the reference electrode outside, not between the anode and the cathode, which is based on Li@Ni and the cell that has undergone a charge/discharge cycle. There is an advantage that an electrode can be used. However, in the case of such a three-electrode cell measurement method, resistance by the electrolyte existing between the reference electrode and the counter electrode acts greatly depending on the wetting of the solution and the position of the reference electrode. Therefore, it is important to position the reference electrode to minimize solution resistance and to wet the electrolyte. In addition, in the conventional three-electrode cell method, it is difficult to control the position of the electrolyte or the reference electrode during the sealing process, and thus, there is a problem in that reproducibility is very poor.

Accordingly, there is a need for a new test method that improves the above problems occurring in the conventional electrode test method using a three-electrode cell.

Korean Patent Publication No. 2016-0047743 Korean Patent Publication No. 2013-0128030

An object of the present invention is to improve the problem of reducing reproducibility due to electrolyte resistance, which was a problem in the method of measuring electrode characteristics using a conventional three-electrode cell, and to provide an electrode test apparatus that is simple to manufacture and has a short manufacturing time, and an electrode characteristic test method using the same. To do.

In order to achieve the above object, the electrode test apparatus according to the present invention includes a battery cell; A mounting member having a battery cell insertion portion into which a battery cell is inserted; And

It may include; a cover member capable of covering and sealing the mounting member.

At this time, the battery cell is provided with a positive electrode tab, a negative electrode tab, and a reference electrode,

The battery cell insertion portion is formed on the mounting member, and one surface is opened to insert the battery cell in a direction parallel to the mounting member.

Meanwhile, the battery cell is provided with an exposed portion in which one end of the electrode assembly is exposed to the outside, and a reference electrode is disposed on the side of the electrode assembly exposed through the exposed portion, so that the battery cell has a positive electrode, a negative electrode, and a reference electrode. A structure of a three-electrode cell is formed.

An electrolyte solution is injected into the insertion portion, and the exposed portion of the battery cell is impregnated with the electrolyte solution injected into the insertion portion. At this time, since the reference electrode is disposed on the side of the electrode assembly of the exposed portion of the impregnated battery cell, and a part of the reference electrode is also impregnated with the electrolyte, ion exchange is performed using the reference electrode as a counter electrode.

Meanwhile, by arranging the reference electrode to face one side of the exposed portion of the electrode assembly, the distance between the reference electrode and the positive and negative active materials may be reduced to a minimum. Accordingly, resistance of the electrolyte can also be minimized.

The reference electrode facing the electrode assembly is disposed close to the side of the electrode assembly, but when the electrode assembly directly contacts, a short circuit occurs inside the battery cell. Accordingly, in order to minimize the distance to the active material and prevent the occurrence of a short circuit, an insulating film may be provided on one surface of the reference electrode facing the side surface of the electrode assembly. In this case, it is preferable to use a polymer membrane having insulating properties as the insulating layer, and when using the same material as the porous polymer membrane, particularly the separator, ion exchange is smooth and thus the most preferable.

In this case, the reference electrode can be manufactured in various forms according to the manufacturing method of a reference electrode known in the art, but it is recommended to manufacture and use a reference electrode in a form of wrapping a metal thin film made of nickel with lithium metal. It is preferable because the process is simple and cost can be reduced. In addition, LTO@Ni electrodes may be used as a reference electrode depending on the purpose of the experiment, such as a long life test.

On the other hand, the insertion portion may be manufactured in a form that can be moved on the mounting member. The battery cell can be manufactured in various shapes and sizes depending on the use and the device to be applied. In the case of manufacturing the insert in a movable form, the size of the internal space of the mounting member in which the battery cell is mounted can be adjusted. It can be applied to various battery cells.

The mounting member may have a groove having a shape corresponding to the shape of the battery cell. The positive electrode tab, the negative electrode tab, and the reference electrode provided in the battery cell protrude to the outside, and since one end of the electrode test apparatus of the present invention is exposed to the outside, there is a possibility that the electrolyte solution inside the battery cell may be lost. Therefore, if the battery cell is mounted by forming a groove corresponding to the shape of the battery cell in the mounting member, the battery cell can be mounted and fixed in a more stable state, and a short circuit due to external shock can be prevented, and loss of electrolyte solution can be reduced. Can be reduced.

In addition, it is preferable that the mounting member and the cover member are made of a material that is insulative and not reactive with the electrolyte so that short circuit or corrosion does not occur at a site in direct contact with the electrode assembly.

Specifically, it is preferable to use one selected from the group consisting of polytetrafluoroethylene and polyethylene as the mounting member and the cover member, and the polytetrafluoroethylene material has excellent processability, and the polyethylene has high mechanical strength and thus stability. This has a high advantage.

By covering the cover member on the mounting member, the electrode testing device of the present invention can be sealed. However, in order to test the electrode characteristics, the positive electrode tab, the negative electrode tab, and the reference electrode must be connected to the charging/discharging device. Therefore, a plurality of connecting members made of a conductive material penetrating the cover member are provided in the cover member, It is possible to electrically connect the positive electrode tab, the negative electrode tab and the reference electrode.

On the other hand, when the mounting member and the cover member are made of polytertafluoroethylene, mechanical stiffness is somewhat lowered, and it may be difficult to maintain a sealed state. Therefore, in order to further increase mechanical strength and stability and maintain a sealed state, a support member for interviewing the outer surfaces of the mounting member and the cover member may be further included. At this time, it is preferable to use a material having excellent mechanical strength as the support member, and since the mounting member and the cover member are made of an insulating material, it may be made of a metal material.

On the other hand, the electrode characteristic test method of the present invention may consist of the following steps.

Manufacturing a pouch-type battery cell;

Manufacturing a reference electrode by wrapping the nickel thin film with lithium metal;

Breaking the battery case of the pouch-type battery cell to expose one end of the electrode assembly;

Placing the reference electrode on the exposed side of the electrode assembly;

Preparing a mounting member capable of accommodating the battery cell;

Forming an insertion part for inserting one end of the battery cell on the mounting member;

Inserting the exposed end of the battery cell into the insertion part;

Injecting an electrolyte into the inner space of the insertion part;

Sealing the mounting member with a sealing member;

Measuring characteristics of a positive electrode or a negative electrode by performing charging and discharging of the battery cell.

Unlike the conventional three-electrode battery cell for electrode testing, the electrode testing method of the present invention hardly generates an error due to electrolyte resistance, and thus precise electrode characteristics can be reproduced. In addition, the electrode testing device of the present invention used for the electrode test has an advantage that the manufacturing time is shorter than that of the conventional three-electrode cell, does not cause problems such as electrolyte leakage, and can be operated in a normal dry room, so that the test is simple. There is this.

1 is a schematic diagram showing an example of a conventional three-electrode battery cell for electrode testing.
2 is a schematic diagram showing another example of a conventional three-electrode battery cell for electrode testing.
3 shows a structure of an electrode test apparatus according to an embodiment of the present invention.
4 shows the structure of an electrode testing apparatus according to another embodiment of the present invention.
5 schematically shows an electrode test apparatus according to another embodiment of the present invention.
6 is a diagram illustrating an operating principle of a storage unit capable of adjusting an internal space of the device according to the size of a battery cell in the electrode testing apparatus according to another embodiment of the present invention.
7 is a graph showing the experimental results of conducting an electrode characteristic test using a three-electrode cell of a conventional method.
8 is a graph showing the experimental results of conducting an electrode characteristic test using the electrode test apparatus according to the present invention.

Since the present invention can add various changes and have various forms, specific embodiments are illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to a specific form disclosed, it should be understood to include all changes, equivalents, and substitutes included in the spirit and scope of the present invention.

In describing each drawing, similar reference numerals are used for similar elements. In the accompanying drawings, the dimensions of the structures are shown to be enlarged than actual for clarity of the present invention. The terms used to describe various components are provided to aid understanding, and the components should not be limited by the terms. These terms are used only for the purpose of distinguishing one component from another component. For example, a first component may be referred to as a second component without departing from the scope of the present invention, and similarly, a second component may be named as a first component. Singular expressions include plural expressions unless the context clearly indicates otherwise.

As used throughout the specification of the present invention, terms such as "include" or "have" are intended to designate the existence of features, numbers, steps, actions, components, parts, or a combination thereof described in the specification. It is to be understood that the possibility of the presence or addition of other features, numbers, steps, actions, components, parts, or combinations thereof, or any further features, is not excluded in advance.

Further, when a part such as a layer, film, region, plate, etc. is said to be "on" another part, this includes not only the case where the other part is "directly above", but also the case where there is another part in the middle. Conversely, when a part such as a layer, film, region, plate, etc. is said to be "under" another part, this includes not only the case where the other part is "directly below", but also the case where there is another part in the middle. In addition, in the specification of the present invention, the term "above" may include a case where it is disposed not only above but also below.

Hereinafter, the present invention will be described in more detail.

In order to achieve the above object, the electrode test apparatus according to the present invention includes a battery cell; A mounting member having a battery cell insertion portion into which a battery cell is inserted; And

It may include; a cover member capable of covering and sealing the mounting member.

A battery cell is mounted and fixed to the mounting member, an electrolyte is injected while the battery cell is mounted, and then the cover member is covered and sealed on the mounting member. Accordingly, the cover member and the mounting member may further include a coupling member or a sealing member for fixing and sealing each other.

On the other hand, the battery cell is provided with a positive electrode tab, a negative electrode tab, and a reference electrode,

The battery cell insertion portion is formed on the mounting member, and one surface is opened to insert the battery cell in a direction parallel to the mounting member. The battery cell insertion unit serves to store the electrolyte so that the inserted battery cell can be impregnated with the electrolyte in addition to the role of fixing the battery cell by inserting it in a vertical direction. That is, the mounting portion and the battery cell insertion portion are erected in a direction perpendicular to the gravity, and the upper portion of the battery cell insertion portion may be open.

The battery cell is provided with an exposed part in which one end of the electrode assembly inside is exposed to the outside for impregnation of the electrolyte solution. Therefore, the electrolyte stored in the insertion portion is impregnated through the electrode assembly of the exposed portion. On the other hand, by disposing the reference electrode on the exposed side of the electrode assembly, the battery cell forms a three-electrode cell structure including a positive electrode, a negative electrode, and a reference electrode. Part of the reference electrode is also impregnated in the electrolyte solution of the insertion part, and through this, the electrode assembly and the reference electrode can be ion-exchanged through the electrolyte solution.

In other words. Part of the electrode assembly is exposed, and the battery cell with the reference electrode disposed on the side of the exposed electrode assembly is inserted perpendicularly to the direction of gravity in the battery cell insertion part, and the electrolyte is injected after the battery cell is inserted. Accordingly, the electrode assembly of the exposed part of the battery cell is impregnated with the electrolyte injected into the insertion part, and a part of the reference electrode disposed on the side of the exposed electrode assembly is also impregnated with the electrolyte, so that the reference electrode is mutually exchanged between the electrode assemblies. do.

At this time, since the reference electrode is disposed facing one side of the exposed portion of the electrode assembly, the distance between the reference electrode and the positive electrode and/or negative electrode active material can be reduced to a minimum, thereby reducing electrode characteristic reproducibility due to resistance of the electrolyte. Can be minimized.

However, since the reference electrode facing the electrode assembly is disposed close to the side surface of the electrode assembly, there is a concern that a short circuit may occur inside the battery cell due to direct contact with the electrode assembly. Accordingly, in order to minimize the distance to the active material and prevent the occurrence of a short circuit, an insulating film may be provided to physically block direct contact between the side surface of the electrode assembly and the reference electrode facing each other.

Specifically, the insulating layer may be provided on one surface of the reference electrode facing the electrode assembly. In this case, it is preferable to use a polymer membrane having insulating properties as the insulating layer, and when using the same material as the porous polymer membrane, particularly the separator, ion exchange is smooth and thus the most preferable.

In this case, the reference electrode may be manufactured in various forms according to a method of manufacturing a reference electrode known in the art. As a method of manufacturing a reference electrode, a method of manufacturing by winding a lithium metal on a metal film made of a nickel material or a method of plating lithium on a copper wire is mainly used. However, in the case of the latter, there is a disadvantage in that operability is inferior since both the manufacturing of the reference electrode and the operation of arranging the reference electrode must be performed within the glove box. On the other hand, since a method of manufacturing a reference electrode in a form of wrapping a metal thin film made of nickel with lithium metal is easily possible in a dry room environment, it is more preferable to use the former method in the present invention.

The battery cell can be manufactured in various sizes and shapes depending on the shape of the electrode assembly inside or the type of device to be applied. Therefore, depending on the battery cell, it is possible to manufacture and use a new device at that time, but in the case of the present invention, by adjusting the internal space of the mounting portion in which the battery cell is mounted, it is possible to overcome the limitation according to the size or shape of the battery cell. To this end, the battery cell insertion unit may be manufactured in a form that is movable on the mounting member, and when the width of the insertion unit is sufficiently enlarged and manufactured to be movable up and down, it can be applied to battery cells having various widths and heights. In addition, battery cells of a special shape such as an'L' shape can be accommodated without problems by moving the battery cell insertion unit to adjust the mounting space. Accordingly, according to the electrode testing device of another embodiment of the present invention, it is possible to measure using various battery cells without additionally manufacturing a separate device.

Meanwhile, the mounting member may have a groove having a shape corresponding to the shape of the battery cell. The positive electrode tab, the negative electrode tab, and the reference electrode provided in the battery cell protrude to the outside, and since one end of the electrode test apparatus of the present invention is exposed to the outside, there is a possibility that the electrolyte solution inside the battery cell may be lost. Therefore, if the battery cell is mounted by forming a groove corresponding to the shape of the battery cell in the mounting member, the battery cell can be mounted and fixed in a more stable state, and a short circuit due to external shock can be prevented, and loss of electrolyte solution can be reduced. Can be reduced.

In addition, it is preferable that the mounting member and the cover member are made of an insulating material so that a short circuit does not occur in a portion in direct contact with the electrode assembly. Specifically, the mounting member and the cover member are made of polytetrafluoroethylene or polyethylene. You can use Polytetrafluoroethylene material is advantageous in that it is very easy to process, and polyethylene has an advantage of high stability due to excellent mechanical strength.

By covering the cover member on the mounting member, the electrode testing device of the present invention can be sealed. Since the positive electrode tab, the negative electrode tab, and the reference electrode are all sealed inside the electrode testing device by covering the cover member, a means for electrically connecting the positive electrode tab, the negative electrode tab, and the reference electrode to an external device is required to perform a test. It should be equipped.

To this end, the cover member may be provided with a connecting member penetrating the cover member in the thickness direction. These connecting members may be made of a conductive material, are provided in plural, and may directly contact the positive electrode tab, the negative electrode tab, and the reference electrode inside the device, and may be electrically connected to an external measuring device. Accordingly, the positions of the connecting members may be determined corresponding to positions of the positive electrode tab, the negative electrode tab, and the reference electrode.

On the other hand, in the case of polytertafluoroethylene, which can be used as a mounting member and a sealing member, mechanical stiffness is rather low, so it may be difficult to maintain the sealed state or stability may be poor. Therefore, in order to further increase mechanical strength and stability and maintain a sealed state, a support member for interviewing the outer surfaces of the mounting member and the cover member may be further included. At this time, it is preferable to use a material having excellent mechanical strength as the support member, and since both the mounting member and the cover member that can directly contact the internal battery cell are made of insulating material, the support member may be made of a metal material. Do.

The electrode characteristic test method of the present invention is as follows.

First, a pouch-type battery cell is manufactured. After preparing a positive electrode, a negative electrode, and a separator having a desired size and shape, the electrode assembly is manufactured by laminating them. It is accommodated in a pouch-type battery case, and an electrolyte is injected to seal it.

Next, the nickel thin film is wrapped with lithium metal to prepare a reference electrode. The reference electrode can also be manufactured by plating a lithium metal on a copper wire, but this method is more preferable since the manufacturing process is difficult and takes a long time.

The bottom of the pouch-shaped case of the battery cell is cut to expose one end of the internal electrode assembly. Then, the prepared reference electrode is placed on one end side of the exposed electrode assembly. In this case, the reference electrode is preferably disposed as close as possible to the electrode assembly, and an insulating layer may be added between the electrode assembly and the reference electrode to prevent a short circuit.

Next, prepare the mounting member. The mounting member may be prepared in advance before the process of preparing the battery cell. After forming a groove in which the battery cell can be mounted on the mounting member, a battery cell insertion part for inserting the battery cell is formed. The battery cell insertion unit may be in the form of a rectangular parallelepiped with one side open, but any shape may be used as long as the battery cell can be inserted and an electrolyte can be injected.

Insert the electrode assembly from one end of the battery cell exposed to the insertion part. After that, the mounting member is erected vertically so that the battery cell stands vertically in the direction of gravity. After that, the electrolyte is injected into the free space of the insertion part into which the battery cell is inserted. By injecting the electrolyte, the exposed portion of the electrode assembly and the reference electrode are impregnated and electrically connected. Since the electrolyte inside the battery cell may flow out from the exposed part and be mixed, it is preferable that the electrolyte injected into the insertion part is the same as the electrolyte injected into the battery cell.

Finally, the mounting member is sealed using a sealing member. At this time, if the material of the mounting member and the sealing member is weak in mechanical strength, a separate support member may be used to further increase rigidity and sealing properties.

A connecting member may be provided in the mounting member to electrically connect the measuring device to the positive electrode tab, the negative electrode tab, and the reference electrode.

Finally, the battery cells are charged and discharged to test the characteristics of the positive or negative electrode.

Hereinafter, a conventional three-electrode cell and an electrode test apparatus of the present invention will be described in more detail with reference to the drawings.

1 shows a three-electrode cell 10 for a conventional electrode characteristic test.

The three-electrode cell 10 includes an anode tab 12, a cathode tab 13, and a reference electrode 14 on the electrode assembly 11. This is followed by first manufacturing an electrode assembly including the positive electrode tab 12 and the negative electrode tab 13, and then attaching the reference electrode 14 to the upper or lower portion of the electrode assembly 11, and then to the pouch-type battery case 15. It is prepared by receiving it, injecting the electrolyte, and sealing it. At this time, the reference electrode 14 is also drawn out together with the positive electrode tab 12 and the negative electrode tab 13. The three-electrode cell of this type is affected by the resistance of the electrolyte filled therebetween because the distance between the reference electrode and the anode and the cathode is long. Therefore, there is a disadvantage in that reproducibility is poor when measuring electrode characteristics.

2 shows a three-electrode cell 20 for testing another type of conventional electrode. Like the three-electrode cell 10 of FIG. 1, the electrode assembly 21 includes an anode tab 22, a cathode tab 23, and a reference electrode 23, and the reference electrode 23 is made of epoxy resin. It is attached to the side of the assembly 11. The three-electrode cell 20 is slightly different from the three-electrode cell 10 of FIG. 1 in a manufacturing method.

First, an electrode assembly 20 in which a conventional positive electrode, a negative electrode, and a separator are stacked is manufactured, and then stored in a pouch-type battery case 26, and an electrolyte is injected to seal it. Thereafter, a part of the side surface of the battery case 26 is cut and the reference electrode 24 is attached to the outside of the electrode assembly. Epoxy resin 25 is used for attachment, and the reference electrode 24 is a copper wire plated with lithium metal. Since this process is performed by first manufacturing a conventional battery cell and then cutting the battery case 26, it must be performed in a glove box. Therefore, there is a disadvantage in that the manufacturing method is difficult and the process takes as long as 1 to 2 days.

3 shows a structure of an electrode testing apparatus 100 according to an embodiment of the present invention. First, the battery cell 110 inserted into the electrode testing apparatus 100 of the present invention includes a positive electrode tab 112, a negative electrode tab 112, and a reference electrode 113. In addition, an exposed portion 114 is formed at one end of the battery cell 110 to expose the electrode assembly by removing the battery case, and the reference electrode 113 is disposed on the side of the electrode assembly from the lower side of the exposed portion 114 Has been.

The battery cell 110 is mounted on the mounting member 120, and a groove for mounting the battery cell may be formed in the mounting member 120. Meanwhile, a battery cell insertion part 130 may be formed in the mounting member 120, and the battery cell 110 is inserted into the battery cell insertion part 130 in a vertical direction from the exposed part 114, and the battery cell After the 110 is inserted, an electrolyte is injected into the free space of the battery cell insertion unit 130, so that the exposed portion 114 and the reference electrode 113 may be impregnated with the electrolyte.

After the battery cell 110 is mounted on the mounting member 120, the cover member 140 is covered and sealed thereon. In this case, the cover member 140 and the mounting member 120 may further include a separate coupling member or a sealing member to increase coupling force and sealing force. A plurality of connection members 141 are formed on the mounting member 140, and each of the connection members 141 is provided with a cover member 140 when the mounting member 120 is covered with a positive electrode tab 111 and a negative electrode. It directly contacts the tab 112 and the reference electrode 113 and serves to electrically connect the external device and the battery.

4 shows a structure of an electrode testing apparatus 200 according to another embodiment of the present invention. Another type of electrode test device 200 of FIG. 4 is a further improvement of the electrode test device 100 of FIG. 3, for applying various battery cells of different shapes and sizes without manufacturing a separate device. will be.

Like the electrode testing device 100 of FIG. 3, the battery cell 210 inserted into the electrode testing device 200 of FIG. 4 includes a positive electrode tab 212, a negative electrode tab 212, and a reference electrode 213. have. In addition, an exposed portion 214 is formed at one end of the battery cell 210 to expose the electrode assembly by peeling the battery case, and the reference electrode 213 is disposed on the side of the electrode assembly from the lower side of the exposed portion 214 Has been.

Further, the battery cell 210 is mounted on the mounting member 220, and a groove for mounting the battery cell may be formed in the mounting member 220. Meanwhile, a battery cell insertion part 230 may be formed in the mounting member 220, and the battery cell 210 is inserted into the battery cell insertion part 230 in a vertical direction from the exposed part 214, and the battery cell After 210 is inserted, an electrolyte is injected into the free space of the battery cell insertion part 130, so that the exposed part 214 and the reference electrode 213 may be impregnated with the electrolyte.

However, in the electrode test apparatus 200 of FIG. 4, the battery cell insertion unit 230 may be moved in a direction parallel to the mounting member 220. That is, the battery cell insertion unit 230 can be moved up and down based on the figure of FIG. 4, and when it is moved upward, the installation space of the battery cell 210 is reduced, and when it is moved downward, the installation space is increased. Therefore, it is not necessary to manufacture a separate device according to the size of the battery cell, and it is possible to apply various battery cells simply by moving the battery cell insertion part 220. To this end, the battery cell insertion unit 230 may be provided on the mounting member 220 in a slidable structure, and in order to secure excellent mobility, the mounting member 220, the battery cell insertion unit 230, and the sealing member ( 240) may be made of polytetrafluoroethylene having flexible physical properties.

Like FIG. 3, after the electrode test apparatus 200 of FIG. 4 also mounts the battery cell 210 to the mounting member 220, the cover member 240 is covered and sealed thereon. At this time, the cover member 240 and the mounting member 220 may further include a separate coupling member or a sealing member to increase the coupling force and sealing force. A plurality of connection members 141 are formed in the mounting member 240. When the mounting member 220 is covered with a cover member 240, each of the connecting members 241 is a positive electrode tab 211 and a negative electrode. The tab 212 and the reference electrode 213 are in direct contact with each other and are electrically connected to an external device.

However, when a polytetrafluoroethylene material is used, the overall sealing property or stability may be deteriorated. In order to compensate for this, it is possible to further improve the stability and sealing strength of the device by using separate support members 251 and 252.

As such, the electrode test according to another embodiment of the present invention in which the battery cell 210, the mounting member 220, the battery cell receiving part 230, the cover member 240, and the support members 251, 252 are all combined The device 200 has the same shape as the schematic diagram of FIG. 5.

Referring to FIGS. 5 and 6 together, the electrode test apparatus 200 according to another exemplary embodiment can be used by adjusting the position of the battery cell accommodating portion when the battery cell is relatively large or small.

7 and 8 are graphs showing results of charging and discharging experiments using the three-electrode cell according to FIG. 1 of the conventional method and the electrode test apparatus 100 according to an embodiment of the present invention. Excluding the difference between the two components, the remaining conditions such as the anode, the cathode, the separator, the electrode assembly, and the type of electrolyte were all the same.

As shown in FIGS. 7 and 8, it can be seen that the solution resistance is low when measured by the electrode testing apparatus of the present invention.

10: 3-electrode battery cell
11: electrode assembly
12: anode tab
13: cathode tab
14: reference electrode
15; Battery case
20: 3-electrode battery cell
21: electrode assembly
22: anode tab
23: cathode tab
24: reference electrode
25: epoxy resin
26: battery case
100: electrode test device
110: battery cell
111: anode tab
112: cathode tab
113: reference electrode
114: electrode assembly exposed portion
120: mounting member
130: battery cell insertion part
140: cover member
141: connecting member
200: electrode test device.
210: battery cell
211: anode tab
212: cathode tab
213: reference electrode
214: electrode assembly exposed portion
220: mounting member
230: battery cell insertion part
240: cover member
241: connecting member
251: support member
252: support member

Claims (14)

Battery cell;
A mounting member having a battery cell insertion portion into which a battery cell is inserted; And
Including; a cover member capable of covering and sealing the mounting member,
The electrode testing apparatus, characterized in that the battery cell is provided with a positive electrode tab, a negative electrode tab, and a reference electrode.
The method of claim 1,
The battery cell electrode testing apparatus, characterized in that it comprises an electrode assembly exposed portion in which one end of the inner electrode assembly is exposed to the outside.
The method of claim 2,
An electrolyte is injected into the insertion part,
The electrode test apparatus, characterized in that the exposed portion of the electrode assembly is impregnated with an electrolyte.
The method of claim 2,
The reference electrode is an electrode testing apparatus, characterized in that disposed to face the one side of the exposed portion of the electrode assembly.
The method of claim 4,
An electrode testing apparatus, characterized in that an insulating film is provided on one surface of the reference electrode facing the electrode assembly.
The method of claim 1,
The reference electrode is an electrode testing apparatus, characterized in that the structure surrounding a thin film of a nickel material with lithium metal.
The method of claim 1,
The battery cell insertion part is formed on the mounting member, the electrode testing device, characterized in that one surface is open to insert the battery cell in a direction parallel to the mounting member.
The method of claim 1,
The electrode testing device, characterized in that the insertion part is movable on the mounting member.
The method of claim 1,
The electrode testing device, wherein the mounting member has a groove having a shape corresponding to the shape of the battery cell.
The method of claim 1,
The electrode testing device, characterized in that the mounting member and the cover member are made of an insulating material.
The method of claim 1,
The mounting member and the cover member are electrode testing apparatus, characterized in that made of one selected from the group consisting of polytetrafluoroethylene and polyethylene.
The method of claim 1,
The cover member includes a plurality of connecting members made of a conductive material penetrating the cover member,
The connecting members, when the mounting member is covered with a cover member and sealed, contact the positive electrode tab, the negative electrode tab, and the reference electrode of the battery cell, respectively.
The method of claim 1,
Electrode specific testing device, characterized in that it further comprises a support member for interviewing the outer surface of the mounting member and the cover member.
Manufacturing a pouch-type battery cell;
Manufacturing a reference electrode by wrapping the nickel thin film with lithium metal;
Breaking the battery case of the pouch-type battery cell to expose one end of the electrode assembly;
Placing the reference electrode on the exposed side of the electrode assembly;
Preparing a mounting member capable of accommodating the battery cell;
Forming an insertion part for inserting one end of the battery cell on the mounting member;
Inserting the exposed end of the battery cell into the insertion part;
Injecting an electrolyte into the inner space of the insertion part;
Sealing the mounting member with a sealing member;
Testing the characteristics of the positive electrode or the negative electrode by performing charging and discharging on the battery cell.

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