KR101989490B1 - Apparatus for Inspection of Welding State of Clad to Battery Cell - Google Patents

Abstract

The present invention relates to a testing tip for applying an impact to a rim of a clad which is welded to an upper surface of a battery cell; And a probe for inspecting a position and a planar view of the clad, wherein the probe is configured such that after the tip for testing has applied a certain force or pressure to the rim of the clad in one direction of the clad, Wherein the clad is inspected for the presence or absence of an abnormality in the position and the planarity of the clad, and the impact, pressurization, and inspection for the rim of the clad are automatically performed.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an apparatus for inspecting a welding state of a clad for a battery cell,

The present invention relates to an apparatus for inspecting a welding condition of a clad for a battery cell.

In recent years, the demand for environmentally friendly alternative energy sources has become an indispensable factor for the future, as the increase in the price of energy sources due to depletion of fossil fuels and the interest in environmental pollution are amplified. Various researches on power generation technologies such as nuclear power, solar power, wind power, and tidal power have been continuing, and electric power storage devices for more efficient use of such generated energy have also been attracting much attention.

Particularly, as technology development and demand for mobile devices increase, the demand for batteries as energy sources is rapidly increasing. Recently, the use of secondary batteries as a power source for electric vehicles (EV) and hybrid electric vehicles (HEV) In addition, the use area has been expanded for use as a power auxiliary power source through a grid, and accordingly, a lot of researches on a battery that can meet various demands have been conducted.

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

However, the lithium secondary battery contains various combustible materials, and there is a danger of overheating or explosion due to overcharging, overcurrent, other physical external impact, etc., and thus has a serious safety drawback. Accordingly, a lithium secondary battery is provided with a positive temperature coefficient (PTC) element, a protection circuit module (PCM), or the like as a safety element capable of effectively controlling an abnormal state such as overcharging or overcurrent, .

In order to electrically connect safety elements such as PTC to battery cells or the like, a large number of connecting members are required. Nickel plates are generally used as such connecting members. However, since the nickel plate is difficult to provide excellent weldability to aluminum or the like used in the battery case, generally, a method of welding a nickel plate after bonding a clad made of a nickel- Has been used.

At this time, the cladding is coupled to one side of the upper end of the battery cell by spot welding, and since the spot welding is performed on the fine portion, the relative bonding force may be weak, It is possible to cause a failure in the electrical connection state between the operation of the cell, which may cause shutdown of the device including the battery cell as a power source, thereby lowering the reliability of the product. , The inspection of the welding condition of the clad is performed during the production of the product.

However, the inspection of the welding condition of such a clad is generally performed by hand, which not only increases manpower and time required for the manufacture of the product, but also makes it difficult to perform precise inspection due to the small size of the clad, There is a problem that the reliability of the process is lowered.

Therefore, there is a high need for a technique capable of fundamentally solving such problems.

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.

The inventors of the present application have conducted intensive research and various experiments and, as will be described later, use an inspection tip and a probe to automatically check whether the position and the flatness of the clad are abnormal By this construction, it is possible to save manpower and time required for the process of inspecting the welding condition of the clad during the manufacturing process of the secondary battery, thereby saving the manufacturing cost as a whole, It has been confirmed that the reliability of the inspection process can be improved, and the present invention has been accomplished.

In order to accomplish the above object, according to the present invention,

A tip for applying an impact to a rim of a clad attached by welding to an upper surface of the battery cell; And

A probe for examining a position and a planar view of the clad;

And,

The probe is inspected for the presence or absence of an abnormality in the position and planarity of the clad after applying a certain force or pressure to the rim of the clad in one direction of the clad,

The impact or pressure on the rim of the clad, and the inspection can be automatically performed.

Therefore, the inspection tip and the probe are configured to automatically check whether there is an abnormality in the position and the flatness of the clad, thereby saving manpower and time required for the process of inspecting the welding state of the clad Therefore, the overall manufacturing cost can be saved, and more precise inspection can be performed by the sensor of the probe, so that the reliability of the inspection process can be improved.

In one specific example, the clad is not particularly limited as long as it is a material having excellent conductivity, and in detail, it may be a structure made of a nickel-aluminum alloy.

Here, the nickel-aluminum alloy may have a structure in which a nickel plating layer is formed on one side of an aluminum plate material, or an aluminum plating layer is formed on one side of a nickel plate material.

Accordingly, the clad is positioned between the upper surface of the battery cell including the battery case made of aluminum and the connection members made of the nickel plate, so that the battery cells and the connection members can be more easily electrically connected by welding.

The cladding may be attached to the upper surface of the battery cell by resistance welding or laser welding. However, if the cladding can be spot welded on the upper surface of the battery cell to be stably bonded, the welding method is limited thereto It is not.

On the other hand, the welding may be performed only on a region of about 50% based on the total size of the clad.

If the welding is carried out only on a small area based on the overall size of the clad, it is difficult for the clad to maintain a stable bonding state with respect to the upper surface of the battery cell, and conversely, The time required for welding the clad is increased, so that the whole process can be delayed.

In this case, the welding may be performed only for the corner portions where the two outer peripheries of the outer periphery of the clad are in contact with each other.

Generally, the clad is formed in a rectangular shape, so that even if welding is performed only on four corner portions of a rectangular shape, the clad can maintain a stable coupled state with respect to the upper surface of the battery cell.

Of course, if the clad is a welding part capable of maintaining a stable state of engagement with the upper surface of the battery cell, the welding part is not limited thereto. Specifically, the welding may be performed only on the central part of each outer periphery of the clad Or may be a structure that has been performed.

In one specific example, the inspection tip may be of a structure made of a plastic material.

More specifically, the inspection tip performs a function of applying a constant force or pressure to the edge of the clad in one direction of the clad, and accordingly, when the inspection tip is made of a metal material, Even if the clad maintains a stable coupling state with respect to the upper surface of the battery cell, a damage such as a fine groove may occur on the rim of the clad due to impact or pressure on the rim of the clad, As a result.

Therefore, the inspection tip may be a structure in which the clad is made of a plastic material having a relatively weak physical property such as strength or hardness.

In addition, the inspection tip may have a structure of a plate-like structure in which the width is narrowed in the direction of a portion in contact with the rim of the clad.

Therefore, the inspection tip can precisely apply impact or pressure to the spot welded portion of the clad formed in a minute size.

On the other hand, the probe faces the upper surface of the clad to detect whether the clad is separated from the initial position and whether the flatness is deformed by a predetermined sensor, thereby checking the position and the planarity of the clad.

Specifically, the probe faces the clad from the top surface of the clad to inspect the position and planarity of the clad after the probe tip is impacted or pressed against the rim of the clad while the probe is positioned on the top surface of the clad .

In this case, the probe may have a structure in which a depressed portion corresponding to the shape and size of the clad is formed on a lower surface facing the upper surface of the clad.

Therefore, when the welding state of the clad is not abnormal, the clad is inserted into the indentation portion of the probe, and thus, the normal state of the clad welding state can be discriminated.

On the other hand, when the clad is detached from the initial position due to impact or pressure by the inspection tip, the clad can not be inserted into the indentation portion of the probe, It is possible to detect it by detecting it.

Further, when the welded portion is separated or broken or deformed by impact or pressure against the rim of the clad, the deformed portion may be bent or bent in the upper or lower direction so that the flatness of the clad may be deformed.

Accordingly, the thickness of the clad becomes larger than the depth of the indentation of the probe. Accordingly, since the clad can not be inserted into the indentation portion of the probe, it is possible to detect the failure of the clad by the sensor have.

For this, the depth of the indent may be 100% to 110% of the thickness of the clad.

If the depth of the depressed portion is less than 100% of the thickness of the clad, the clad can not be entirely inserted into the depressed portion. Therefore, the edge of the depressed portion can not face the upper surface of the battery cell, If the depth of the indentation exceeds 110% of the thickness of the clad, even if the flatness of the clad is slightly changed, the clad is stably inserted into the indentation portion , It can not be easily detected whether or not the flatness of the clad is deformed.

Therefore, the depth of the indentation is 100% to 110% of the thickness of the clad, so that the flatness of the clad can be easily detected.

In one specific example, the testing apparatus may further include a sorting device that automatically classifies the battery cells that have been inspected, according to whether there is an abnormality or not.

In other words, the inspection apparatus inspects the welding condition of the clad by the inspection tip and the probe, and then, in order to transfer the battery cell to the next process, As shown in FIG.

In this case, the battery cell in which the abnormality is not detected among the battery cells having been inspected is automatically transferred to the next process, and the abnormal battery cell can be automatically discharged to a separate space for recovery.

Therefore, the abnormal battery cell is recovered separately, and only the abnormal battery cell is automatically transferred to the next process, so that the defective rate of the finished product can be effectively reduced through the subsequent process.

Further, the present invention provides a method for inspecting a welding state of a clad attached to an upper surface of a battery cell by welding with the clad welding state inspection apparatus,

A step of applying a predetermined impact to the rim of the clips attached to the upper surface of the battery cell at a constant interval and a predetermined number of times;

Detecting whether or not the clad of the process (a) is detached from the initial position and whether or not the deformation has been deformed by the sensor;

A step of classifying the battery cells having been inspected in the step (b) according to the presence or absence of abnormality and transferring the cells to a next process or discharging the cells to a separate collection space;

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In this case, the processes (a) to (c) can be performed automatically by the integrated inspection apparatus, thereby saving manpower and time required for the inspection process, Cost can be saved and more precise inspection can be performed by the sensor of the probe, so that the reliability of the inspection process can be improved as compared with a manual inspection.

According to another aspect of the present invention, there is provided a battery cell manufactured through the inspection method and a battery pack including the battery cell, wherein the battery pack includes a protective circuit module (PCM) and a PTC device May be connected by the connecting members.

In this case, at least one of the connecting members may be a structure that is bonded to the clad by welding.

As described above, if the cladding can be spot welded on the upper surface of the battery cell and can be stably bonded, the welding method is not limited so long as at least one of the connecting members is resistance welding or Or may be a structure that is bonded to the clad by laser welding.

The present invention also provides a device including the battery pack, and the specific types and structures of the device are well known in the art, so a detailed description thereof will be omitted herein.

INDUSTRIAL APPLICABILITY As described above, the clad welding state inspection apparatus according to the present invention is configured to automatically check the position and the flatness of the clad using a tip and a probe for inspection, It is possible to save manpower and time required for the process of inspecting the welding state of the clad during the manufacturing process of the clad, thereby saving the manufacturing cost as a whole, and performing a more precise inspection by the sensor of the probe Therefore, the reliability of the inspection process can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view showing various clad welded portions of a battery cell to be inspected by a clad welded state inspection apparatus according to an embodiment of the present invention; FIG.
2 is a schematic view schematically showing the structure of a testing tip of a clad welding apparatus according to an embodiment of the present invention;
3 is a schematic view schematically showing the structure of a probe of a clad welding apparatus according to one embodiment of the present invention;
4 is a schematic view illustrating a process of inspecting a clad welding state of a battery cell in a steady state by a welding apparatus according to another embodiment of the present invention;
5 and 6 are schematic views illustrating a process of inspecting a clad welded state of a battery cell in an abnormal state by a welding apparatus according to another embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to the drawings according to the embodiments of the present invention, but the scope of the present invention is not limited thereto.

FIG. 1 is a schematic view schematically showing various clad welded portions of a battery cell inspected by a clad welded state inspection apparatus according to an embodiment of the present invention.

Referring to FIG. 1, claddings 111 and 121 are welded at one end to the upper ends of the battery cells 110 and 120, respectively.

Each of the claddings 111 and 121 is coupled by a spot welding method and the clad 111 coupled to one battery cell 110 has corner portions 111a, 111b, 111c, and 111d are welded and combined.

The clad 121 coupled to another battery cell 120 is welded only to the central portions 121a, 121b, 121c, and 121d of the respective outer peripheries.

FIG. 2 is a schematic view schematically showing the structure of an inspection tip of a clad welding apparatus according to an embodiment of the present invention.

Referring to FIG. 2, the inspecting tip 200 has one end connected to the automation apparatus 210, and the other end opposite to the inspecting tip 200 is formed with a tip portion 220 contacting the edge of the clad.

The inspection tip 200 has a structure in which the width of the inspection tip 200 is gradually narrowed in the direction of the tip portion 220 which contacts the edge of the clad from one side end portion connected to the automatic device 210 in a plan view.

The inspection tip 200 is a plate-like structure, and has a uniform thickness as a whole in a vertical section.

3 is a schematic view schematically showing a structure of a probe of a clad welding apparatus according to an embodiment of the present invention.

Referring to FIG. 3, the probe 300 has a depressed portion 310 formed on a lower surface thereof facing the upper surface of the clad.

The indentation 310 has a rectangular shape corresponding to the shape of the clad and has a size corresponding to the clad.

The depth D of the indent 310 is in the range of 100% to 110% of the thickness of the clad.

Therefore, when the probe 300 faces the upper surface of the clad, the clad in the steady state is inserted into the indent 310 of the probe 300, And the outer peripheral edge 320 of the indent 310 formed on the lower surface of the probe 300 contacts the upper surface of the battery cell to sense the normal state of the clad.

On the other hand, the clad in an abnormal state can not be inserted into the indent 310 of the probe 300 because the clad in the unsteady state is displaced from the initial position or the top view is deformed due to the deformation of the shape, The outer peripheral edge 320 of the indent 310 formed on the lower surface of the probe 300 can not contact the upper surface of the battery cell and thus the failure of the clad can be detected have.

FIG. 4 is a schematic view showing a process of inspecting a clad welding state of a battery cell in a steady state by a welding apparatus according to another embodiment of the present invention.

4, the inspecting tip 430 applies a predetermined pressure to the rim of the clad 420 in the rear direction coupled to the upper surface of the battery cell 410, It is separated.

The probe 440 located on the upper surface of the battery cell 410 moves downward so that the recessed portion 441 of the lower surface thereof faces the upper surface of the clad 420 .

The outer peripheral end portion 442 of the indentation portion 441 is stably inserted into the indent portion 441 of the probe 440 and the outer peripheral end portion 442 of the indent portion 441 is inserted into the battery cell 410, As shown in Fig.

The probe 440 which has been inspected for the presence or absence of abnormality of the clad 420 is moved upward in the direction of the upper surface of the clad 420 to be separated from the clad 420.

5 and 6 are schematic views schematically illustrating a process of inspecting a clad welded state of a battery cell in an abnormal state by a welding apparatus according to another embodiment of the present invention.

5, the inspecting tip 530 applies a predetermined force to the edge of the clad 520 in the rear direction of the clad 520 coupled to the upper surface of the battery cell 510 do.

As a result, the portion of the clad 520 that has a poor welding state is separated from the upper surface of the battery cell 510, and the clad 520 is released from the initial position.

Thereafter, the inspecting tip 530 is separated from the clad 520. When the inspecting tip 530 is viewed from the side of the battery cell 510, the probe 540 located on the upper surface of the battery cell 510 contacts the recessed portion 541 Is moved downward so as to face the upper surface of the clad 520.

The clad 520 is not inserted into the indentation 541 of the probe 540 because the part of the weld is separated and released from the initial position by the pressing of the inspection tip 530, The outer peripheral edge 542 of the battery cell 510 does not contact the upper surface of the battery cell 510.

The outer peripheral end 542 of the indentation 541 formed on the lower surface of the probe 540 can not move in the predetermined direction of the battery cell 510 It is not possible to contact the upper surface of the clad 520, so that the failure of the clad 520 can be detected.

The probe 540 which has been inspected for the presence or absence of abnormality of the clad 520 is moved upward in the direction of the upper surface of the clad 520 to be separated from the clad 520.

6, the inspection tip 630 applies a constant force to the edge of the clad 620 in the lateral direction of the clad 620 coupled to the upper surface of the battery cell 610.

As a result, the portion of the clad 620 where the welding state is poor is separated from the upper surface of the battery cell 610, the shape of the clad 620 is deformed, and the flatness is deformed.

The probe 640 located on the upper surface of the battery cell 610 is separated from the cladding 620 by the indentation 641 of the lower surface of the battery cell 610 Is moved downward so as to face the upper surface of the clad 620.

The clad 620 is not completely inserted into the indent 641 of the probe 640 because the entire flat surface is deformed as a part of the welding portion is separated and deformed due to the pressing of the inspection tip 630, The outer peripheral end 642 of the indent 641 is not in contact with the upper surface of the battery cell 610. [

The outer peripheral end 642 of the indent 641 formed on the lower surface of the probe 640 is positioned at a predetermined distance from the center of the battery cell 610 It is impossible to contact the upper surface, so that the failure of the clad 620 can be detected.

The probe 640 which has been inspected for the presence or absence of abnormality of the clad 620 is moved upward in the direction of the upper surface of the clad 620 to be separated from the clad 620.

Those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims (19)

A tip for applying an impact to a rim of a clad attached by welding to an upper surface of the battery cell; And
A probe for detecting a position and a planarity of the clad by detecting a deviation of the clad from the initial position and a deformation of the planar view by a predetermined sensor by facing the upper surface of the clad;
And,
The probe is inspected for the presence or absence of an abnormality in the position and planarity of the clad after applying a certain force or pressure to the rim of the clad in one direction of the clad,
Impact or pressure on the rim of the clad and inspection are automatically performed,
The probe has a depressed portion corresponding to the shape and the size of the clad on the lower surface facing the upper surface of the clad,
When the clad is inserted into the indentation portion, the outer peripheral end of the indent formed on the lower surface of the probe contacts the upper surface of the battery cell, thereby detecting the normal state of the clad In addition,
Wherein the depth of the indent is 100% to 110% of the thickness of the clad. The apparatus of claim 1, wherein the clad is made of a nickel-aluminum alloy. The apparatus according to claim 1, wherein the clad is attached to the upper surface of the battery cell by resistance welding or laser welding. The apparatus according to claim 1, wherein the welding is performed only on a portion of about 50% of the entire size of the clad. 5. The apparatus of claim 4, wherein the welding is performed only on edge portions of the outer periphery of the clad that are in contact with the outer periphery of the cladding. 5. The apparatus according to claim 4, wherein the welding is performed only on a central portion of each outer periphery of the clad. The apparatus according to claim 1, wherein the inspection tip is made of a plastic material. The apparatus of claim 1, wherein the inspecting tip comprises a plate-like structure having a narrow width in a direction of a portion contacting the rim of the clad. delete delete delete The apparatus according to claim 1, wherein the inspection apparatus further comprises a sorting device that automatically classifies the tested cells in accordance with an abnormality. 13. The method according to claim 12, wherein the battery cell in which the abnormality is not detected is automatically transferred to the next process, and the abnormal cell cell is automatically discharged into a separate space for recovery, Device. A method for inspecting a welding state of a clad attached by welding to an upper surface of a battery cell by the inspection apparatus according to claim 1,
(a) applying a predetermined impact to a rim of a clad attached to an upper surface of the battery cell at a predetermined interval and a predetermined number of times;
(b) detecting whether or not the clad of the process (a) is separated from the initial position and whether or not the shape is deformed by the sensor to check for the abnormality;
(c) sorting the tested cells of the process (b) according to the presence or absence of abnormality and transferring the cells to the next process or discharging the cells to a separate collection space;
The method comprising the steps of: The method according to claim 14, wherein the steps (a) to (c) are performed automatically by an integrated inspection apparatus. delete delete delete delete

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