Method for inspecting battery welding status

Abstract

This invention relates to a method for inspecting the welding condition of a battery, wherein the welding condition of a cylindrical battery is inspected. The cylindrical battery includes: a cylindrical jelly roll, wherein a first current collector, a first separator, a second current collector, and a second separator are sequentially stacked and wound to extend in a vertical direction; a first current collector plate coupled to the upper end of the jelly roll and the first current collector being first welded to its lower surface; and a second current collector plate coupled to the lower end of the jelly roll and the second current collector being second welded to its upper surface. The method for inspecting the battery welding condition includes a first measurement step, a second measurement step, a first welding determination step, and a second welding determination step.

Description

TECHNICAL FIELD

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2021-0089920, filed on July 8, 2021, the entire disclosure of which is incorporated herein by reference for all purposes.

[0002] The present disclosure relates to a method for inspecting a battery welding state, and more particularly, to a method for inspecting a battery welding state capable of quickly and non-destructively inspecting a state of an electrode of a cylindrical battery. BACKGROUND

[0003] Generally, a current collector to which an active material is applied and an electrode tab for electrical connection with an external electrical device are physically and electrically connected together in a battery by welding. In the case of a poor welding state, the operating efficiency of the battery is reduced, and depending on the situation, the poor welding state can cause damage to the battery. Therefore, it is essential to accurately determine the welding state.

[0004] For a cylindrical battery, there are welding points between the current collector and the electrode tab and between the electrode tab and the can. In order to inspect the welding state of these welding points, a destructive inspection method is performed for manual sampling of the welding area.

[0005] Therefore, the conventional method has problems such as mass suspension when a welding state problem occurs.

[0006] In order to solve this problem, a new inspection method capable of comprehensive inspection on-line is required. SUMMARY

[0007] Technical object

[0008] The present disclosure relates to a method for inspecting a battery welding state, and the purpose is to provide a method for inspecting a battery welding state capable of quickly and non-destructively inspecting a state of an electrode of a cylindrical battery.

[0009] The technical objects to be achieved by the present disclosure are not limited to the aforementioned technical problems, and other technical objects not mentioned will be clearly understood by a person of ordinary skill in the art to which the present disclosure pertains from the following description.

[0010] Technical solution

[0011] An exemplary embodiment of a method for inspecting the welding state of a battery includes: a first measurement step of measuring resistance by contacting a first probe unit with an upper surface of a first current collector plate; a second measurement step of measuring resistance by contacting a second probe unit with a lower surface of a second current collector plate; a first welding determination step of determining a first welding state based on the resistance value measured in the first measurement step; and a second welding determination step of determining a second welding state based on the resistance value measured in the second measurement step.

[0012] Beneficial effects

[0013] The method for inspecting the welding status of a battery according to an exemplary embodiment of the present disclosure can perform a comprehensive online inspection, thereby improving the quality of battery production and removing defective batteries in advance.

[0014] The method for inspecting the welding status of a battery according to an exemplary embodiment of the present disclosure can identify the welding quality within a short period of time. Attached Figure Description

[0015] Figure 1 This is a 3D view showing a jelly roll.

[0016] Figure 2 This is a cross-sectional view showing the coupling between the first current collector plate, the second current collector plate, and the jelly roll.

[0017] Figure 3 This is a block diagram illustrating the method of this disclosure for inspecting the welding condition of a battery.

[0018] Figure 4 This is a conceptual diagram illustrating the first and second measurement steps.

[0019] Figure 5 This is a conceptual diagram illustrating the principles of the first welding determination step and the second welding determination step.

[0020] Figure 6 This is a plan view showing the first collector panel.

[0021] Figure 7 This is a plan view showing the second collector panel.

[0022] Figure 8 This is a cross-sectional view showing a cylindrical battery.

[0023] Figure 9 This is a block diagram illustrating another exemplary embodiment of the method for inspecting the welding status of a battery according to the present disclosure.

[0024] Figure 10 This is a conceptual diagram illustrating the third measurement step.

[0025] Figure 11 This is a conceptual diagram illustrating the fourth measurement step. Detailed Implementation

[0026] An exemplary embodiment of a method for inspecting the welding status of a battery may include: a first measurement step of measuring resistance by contacting a first probe unit with the upper surface of a first current collector plate; a second measurement step of measuring resistance by contacting a second probe unit with the lower surface of a second current collector plate; a first welding determination step of determining the status of a first welding based on the resistance value measured in the first measurement step; and a second welding determination step of determining the status of a second welding based on the resistance value measured in the second measurement step.

[0027] In an exemplary embodiment of the method for inspecting the welding state of a battery, a first probe unit may include a plurality of first probes arranged in a plurality of pairs, and a second probe unit may include a plurality of second probes arranged in a plurality of pairs, wherein in a first measurement step, the plurality of first probes can measure resistance values ​​by contacting different points on a first current collector plate, and in a second measurement step, the plurality of second probes can measure resistance values ​​by contacting different points on a second current collector plate.

[0028] In an exemplary embodiment of the method for inspecting the welding state of a battery, a first current collector plate may be configured as a cross shape in which a first linear region and a second linear region intersect, and a second current collector plate may be configured as a cross shape in which a third linear region and a fourth linear region intersect. The overlapping area of ​​the first and second linear regions may be defined as a first intersecting region, and the overlapping area of ​​the third and fourth linear regions may be defined as a second intersecting region. In a first measurement step, at least one pair of first probes among a plurality of first probes may contact the first linear region to measure a first resistance value while the first intersecting region is between them, and at least another pair of first probes among a plurality of first probes may contact the second linear region to measure a second resistance value while the first intersecting region is between them. In a second measurement step, at least one pair of second probes among a plurality of second probes may contact the third linear region to measure a third resistance value while the second intersecting region is between them, and at least another pair of second probes among a plurality of second probes may contact the fourth linear region to measure a fourth resistance value while the second intersecting region is between them.

[0029] In the first welding determination step of the method for checking the welding state of a battery in an exemplary embodiment, the state of the first welding can be determined based on a first resistance value and a second resistance value, and in the second welding determination step, the state of the second welding can be determined based on a third resistance value and a third resistance value.

[0030] In the exemplary embodiment of the method for inspecting the welding status of a battery, an arcuate adhesive portion may be provided at the edge of the first current collector, and the cylindrical battery may further include: a can housing configured to house a jelly roll inside, wherein the adhesive portion is thirdly welded to the inner circumferential surface of the can housing; and electrode terminals fixed to the lower end of the can housing with an insulator therebetween, and fourthly welded to the second current collector plate.

[0031] An exemplary embodiment of the method for checking the welding state of a battery may further include: after a second welding determination step, a third measurement step, measuring a resistance value by contacting a probe with a first current collector and contacting another probe with the outer peripheral surface of the can housing; a fourth measurement step, measuring a resistance value by contacting a probe with a second current collector and contacting another probe with an electrode terminal; a third welding determination step, determining a third welding state based on the resistance value measured in the third measurement step; and a fourth welding determination step, determining a fourth welding state based on the resistance value measured in the fourth measurement step.

[0032] Resistance measurements in the first, second, third, and fourth measurement steps of the exemplary embodiment of the method for checking the welding status of a battery can be performed using the four-wire low-resistance DC method.

[0033] An exemplary embodiment of a method for manufacturing a battery may include: a jelly roll forming step, forming a jelly roll by sequentially stacking a first current collector, a first separator, a second current collector, and a second separator; a first welding step, firstly welding the first current collector and a first current collector plate to the upper end of the jelly roll; a second welding step, secondly welding a second current collector and a second current collector plate to the lower end of the jelly roll; a first welding determination step, measuring resistance by contacting a first probe unit with the upper surface of the first current collector plate, and determining the state of the first welding based on the measured resistance value; and a second welding determination step, measuring resistance by contacting a second probe unit with the lower surface of the second current collector plate, and... The second welding state is determined based on the measured resistance value; the third welding step involves welding the first current collector plate and the tank shell together; the fourth welding step involves welding the second current collector plate and the electrode terminals together; the third welding determination step involves measuring the resistance by contacting the first current collector plate with a probe and contacting the outer peripheral surface of the tank shell with another probe, and determining the third welding state based on the measured resistance value; the fourth welding determination step involves measuring the resistance by contacting the second current collector plate with a probe and contacting the electrode terminals with another probe, and determining the fourth welding state based on the measured resistance value; and the sealing step involves injecting electrolyte into the tank shell and sealing the tank shell.

[0034] Way of implementing the invention

[0035] Hereinafter, exemplary embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. For clarity and ease of explanation, the dimensions or shapes of the components shown in the drawings may be exaggerated. Furthermore, the terminology specifically defined in consideration of the configuration and operation of this disclosure may vary depending on the intent or habit of the user or operator. The definitions of these terms should be based on the context of the entire specification.

[0036] In the description of this disclosure, it should be noted that the orientations or positional relationships indicated by terms such as “center,” “up,” “down,” “left,” “right,” “vertical,” “horizontal,” “inner,” “outer,” “one side,” and “the other side” are based on the orientations or positional relationships shown in the accompanying drawings or the orientations or positional relationships typically arranged when using the product according to this disclosure, and are used only for the description and brief illustration of this disclosure, and should not be construed as limiting this disclosure, as they do not suggest or imply that the illustrated equipment or components must be configured or operated in the specified orientations.

[0037] Figure 1 This is a three-dimensional view showing the jelly roll 100. Figure 2 This is a cross-sectional view showing the coupling between the first current collector plate 210, the second current collector plate 220, and the jelly roll. Figure 3 This is a block diagram illustrating the method of this disclosure for inspecting the welding condition of a battery. Figure 4 This is a conceptual diagram showing the first measurement step S100 and the second measurement step S200. Figure 5 This is a conceptual diagram illustrating the principles of the first welding determination step S300 and the second welding determination step S400. Figure 6 This is a plan view showing the first collector panel 210. Figure 7 This is a plan view showing the second collector panel 220. Figure 8 This is a cross-sectional view showing a cylindrical battery. Figure 9 This is a block diagram illustrating another exemplary embodiment of the method for inspecting the welding status of a battery according to the present disclosure. Figure 10 This is a conceptual diagram showing the third measurement step S500. Figure 11 This is a conceptual diagram showing the fourth measurement step S600.

[0038] The following text will refer to Figures 1 to 11 The method disclosed herein for inspecting the welding condition of a battery is described in detail.

[0039] The method disclosed herein for inspecting the welding condition of a battery can be used to inspect the welding condition between components used for electrical connection in a cylindrical battery.

[0040] like Figure 1 and Figure 2As shown, the cylindrical battery inspected according to the method for inspecting the welding status of the battery disclosed herein may include: a jelly roll 100, which is cylindrical and extends in the vertical direction with the first current collector 110, the first separator 130, the second current collector 120 and the second separator 140 being sequentially stacked and wound; a first current collector plate 210 coupled to the upper end of the jelly roll 100, wherein the first current collector 110 is first welded to the lower surface of the first current collector plate 210; and a second current collector plate 220 coupled to the lower end of the jelly roll 100, wherein the second current collector 120 is second welded to the upper surface of the second current collector plate 220.

[0041] In other words, such as Figure 1 As shown, the jelly roll 100 can be configured as a cylinder with the vertical direction as the central axis, and the upper end of the first collector 110 can protrude higher than the upper ends of the second collector 120, the first separator 130 and the second separator 140, and the lower end of the second collector 120 can protrude lower than the lower ends of the first collector 110, the first separator 130 and the second separator 140.

[0042] The first current collector 110 can be a negative current collector or a positive current collector coated with a negative electrode active material or a positive electrode active material. When the first current collector 110 is a negative current collector, the second current collector 120 can be a positive current collector, and when the first current collector 110 is a positive current collector, the second current collector 120 can be a negative current collector.

[0043] like Figure 2 As shown, the first current collector plate 210 and the second current collector plate 220 can be configured as planar plates orthogonal to the vertical direction. The upper end of the first current collector 110 can be first welded to the lower surface of the first current collector plate 210 at an inclined angle, and the lower end of the second current collector 120 can be second welded to the upper surface of the second current collector plate 220 at an inclined angle.

[0044] The first and second welds can be laser welding, ultrasonic welding, resistance welding, etc.

[0045] like Figure 3 As shown, the method for inspecting the welding status of a battery disclosed herein may include:

[0046] First measurement step S100: The resistance is measured by bringing the first probe unit 400 into contact with the upper surface of the first current collector plate 210;

[0047] Second measurement step S200: The resistance is measured by bringing the second probe unit 500 into contact with the lower surface of the second current collector plate 220;

[0048] First welding determination step S300: The state of the first welding is determined using the resistance value measured in the first measurement step S100; and

[0049] Second welding determination step S400: The state of the second welding is determined using the resistance value measured in the second measurement step S200.

[0050] The first measurement step S100 and the second measurement step S200 can be performed during battery manufacturing, after the current collector is welded to the current collector plate and before the jelly roll 100 is inserted into the can housing 310.

[0051] like Figure 4 As shown, in the first measurement step S100, the first probe unit 400 can contact one side of the first current collector plate 210—this side is opposite to the side where the first current collector 110 and the first current collector plate 210 are in contact with each other—and in the second measurement step S200, the second probe unit 500 can contact one side of the second current collector plate 220—this side is opposite to the side where the second current collector 120 and the second current collector plate 220 are in contact with each other, thereby allowing the measurement of the resistance value. Figure 5 As shown, even when measuring resistance by contacting the probe with the opposite side of the weld side, the weld condition affects the resistance seen by the probe, so the weld condition on the side opposite to the measurement side can be identified by analyzing the resistance value. In the cylindrical battery subjected to the method of checking the weld condition of the battery disclosed herein, the materials of the first current collector plate 210 and the second current collector plate 220 can be selected from aluminum, nickel, copper, and combinations thereof. The first current collector plate 210 and the second current collector plate 220 can be formed with a thickness ranging from 0.2T to 0.4T. Therefore, the weld condition can be well reflected in the resistance value measured by contacting the probe with the opposite side of the weld side.

[0052] In the method for inspecting the welding status of a battery disclosed herein, a first probe unit 400 may include a plurality of first probes 410 arranged in a plurality of pairs, and a second probe unit 500 may include a plurality of second probes 510 arranged in a plurality of pairs. In a first measurement step S100, the plurality of first probes 410 contact different points of a first current collector plate 210 to measure resistance values, and in a second measurement step S200, the plurality of second probes 510 contact different points of a second current collector plate 220 to measure resistance values.

[0053] A pair of first probes 410 can be configured to include a negative probe and a positive probe, and a pair of second probes 510 can be configured to include a negative probe and a positive probe.

[0054] Each of the multiple pairs of first probes 410 can contact different points, such that the first welding area 214 is located between the negative probe and the positive probe, and each of the multiple pairs of second probes 510 can contact different points, such that the second welding area 224 is located between the negative probe and the positive probe.

[0055] like Figure 6 and Figure 7 As shown, in a cylindrical battery subjected to the method for inspecting the welding state of a battery disclosed herein, the first current collector plate 210 can be configured as a cross shape in which the first linear region 211 and the second linear region 212 intersect, and the second current collector plate 220 can be configured as a cross shape in which the third linear region 221 and the fourth linear region 222 intersect.

[0056] In this case, the overlapping area of ​​the first linear region 211 and the second linear region 212 can be defined as the first cross region 213, and the overlapping area of ​​the third linear region 221 and the fourth linear region 222 can be defined as the second cross region 223. In the first measurement step S100, at least one pair of the plurality of first probes 410 can measure the first resistance value by contacting the first linear region 211 with the first cross region 213 in between, and at least another pair of the plurality of first probes 410 can measure the second resistance value by contacting the second linear region 212 with the first cross region 213 in between, and in the second measurement step S200, at least one pair of the plurality of second probes 510 can measure the third resistance value by contacting the third linear region 221 with the second cross region 223 in between, and at least another pair of the plurality of second probes 510 can measure the fourth resistance value by contacting the fourth linear region 222 with the second cross region 223 in between.

[0057] Specifically, a pair of first probes 410 can contact the first linear region 211 when the first welding region 214 and the first intersection region 213 are located therebetween; more specifically, the pair of first probes 410 can contact both ends of the first linear region 211. Another pair of first probes 410 can also contact the second linear region 212 when the first welding region 214 and the first intersection region 213 are located therebetween; more specifically, the other pair of first probes 410 can contact both ends of the second linear region 212.

[0058] A pair of second probes 510 can contact a third linear region 221 when the second welding region 224 and the second intersection region 223 are located therebetween; more specifically, a pair of second probes 510 can contact both ends of the third linear region 221. Another pair of second probes 510 can also contact a fourth linear region 222 when the second welding region 224 and the second intersection region 223 are located therebetween; more specifically, another pair of second probes 510 can contact both ends of the fourth linear region 222.

[0059] In the first welding determination step S300, the state of the first weld can be determined based on a first resistance value and a second resistance value. In the second welding determination step S400, the state of the second weld can be determined based on a third resistance value and a fourth resistance value. By combining the first and second resistance values, the overall state of the first weld can be identified. Furthermore, if necessary, the welding state of a local area within the first weld region 214 can also be individually identified as an independent value. Similarly, by combining the third and fourth resistance values, the overall state of the second weld can be identified. Furthermore, if necessary, the welding state of a local area within the second weld region 224 can also be individually identified as an independent value.

[0060] like Figure 4 As shown, the resistance measurement in the first measurement step S100 and the second measurement step S200 can be performed using the four-wire low-resistance DC method. The negative probe and the positive probe may each include a terminal connected to an ammeter and a terminal connected to a voltmeter, respectively.

[0061] The method disclosed herein for inspecting the battery welding condition may require accurate measurement of resistance values ​​below 1Ω, and for this purpose, a four-wire low-resistance DC method is preferably used, which can minimize the influence of any wiring resistance or contact resistance.

[0062] like Figure 8 As shown, in the method for inspecting the welding status of a battery disclosed herein, an arc-shaped adhesive portion 215 may be provided at the edge of the first current collector plate 210, and the cylindrical battery may further include: a can housing 310 configured to house the jelly roll 100 inside, wherein the adhesive portion 215 is thirdly welded to the inner circumferential surface of the can housing 310; and electrode terminals 320, which are fixed to the lower end of the can housing 310 with an insulator 330 between them and are fourthly welded to the second current collector plate 220.

[0063] The outer shell 310 may be cylindrical with an open upper end into which the jelly roll 100 may be inserted. An opening 311 may be formed at the lower end of the outer shell 310, such that the electrode terminal 320 may be exposed to the outside of the outer shell 310 through the opening 311, and in which it may contact the second current collector 220.

[0064] like Figure 9 As shown, the method for inspecting the welding status of a battery disclosed herein may further include:

[0065] After the second welding determination step S400

[0066] Third measurement step S500: The resistance value is measured by bringing a probe into contact with the first current collector plate 210 and bringing another probe into contact with the outer peripheral surface of the tank shell 310;

[0067] Fourth measurement step S600: The resistance value is measured by contacting the probe with the second current collector plate 220 and contacting the other probe with the electrode terminal 320;

[0068] Third welding determination step S700: Determine the state of the third weld based on the resistance value measured in the third measurement step S500; and

[0069] Fourth welding determination step S800: The state of the fourth welding is determined based on the resistance value measured in the fourth measurement step S600.

[0070] like Figure 10 As shown, in the third measurement step S500, the resistance value can be measured by contacting the probe with the first current collector plate 210 and the other probe with the outer peripheral surface of the tank shell 310. In the third measurement step S500, the positive probe and the negative probe can be arranged such that the first welding area 214 is not located between the positive probe and the negative probe.

[0071] like Figure 11 As shown, the resistance value can be measured by contacting the probe with the second current collector plate 220 and by contacting the other probe with the electrode terminal 320. Specifically, the resistance value can be measured by contacting the probe with the upper surface of the second current collector plate 220 through the central tube 150 located on the central axis of the jelly roll 100 and by contacting the lower end of the electrode terminal 320 from outside the can housing.

[0072] In the third measurement step S500 and the fourth measurement step S600, resistance measurement can also be performed using the four-wire low-resistance DC method.

[0073] A method for manufacturing a battery using the method for inspecting the welding status of a battery disclosed herein may include:

[0074] Jelly roll 100 forming steps: Jelly roll 100 is formed by sequentially stacking the first current collector 110, the first separator 130, the second current collector 120 and the second separator 140.

[0075] First welding step: First current collector 110 and first current collector plate 210 are first welded to the upper end of jelly roll 100;

[0076] Second welding step: The second current collector 120 and the second current collector board 220 are welded to the lower end of the jelly roll 100.

[0077] First welding determination step: The resistance is measured by bringing the first probe unit 400 into contact with the upper surface of the first current collector plate 210, and the state of the first welding is determined based on the measured resistance value.

[0078] The second welding determination step involves measuring the resistance by bringing the second probe unit 500 into contact with the lower surface of the second current collector plate 220, and determining the state of the second welding based on the measured resistance value.

[0079] Third welding step: Perform a third welding on the first current collector plate 210 and the tank shell 310;

[0080] Fourth welding step: Perform a fourth welding on the second current collector board 220 and the electrode terminal 320;

[0081] The third welding determination step involves measuring the resistance by contacting a probe with the first current collector plate 210 and another probe with the outer peripheral surface of the tank shell 310, and determining the third welding state based on the measured resistance value.

[0082] The fourth welding determination step involves measuring resistance by contacting a probe with the second current collector plate 220 and another probe with the electrode terminal 320, and determining the fourth welding state based on the measured resistance values; and

[0083] Sealing step: Inject the electrolyte into the outer shell 310 of the tank and seal the outer shell 310 of the tank.

[0084] According to an exemplary embodiment, the method for manufacturing a battery measures the resistance value at the welding position between each process and immediately identifies the corresponding welding state, thereby preventing defective products from entering the final process in advance and inspecting the welding state of each component individually without damaging the battery.

[0085] While exemplary embodiments according to this disclosure have been described above, they are merely exemplary, and those skilled in the art will understand that various modifications and equivalents are possible based on these exemplary embodiments. Therefore, the true scope of protection of this disclosure should be defined by the appended claims.

[0086] [Explanation of reference numerals in the attached figures]

[0087] 100…Jelly Roll 110…Episode 1: Appliances

[0088] 120…Second collector 130…First separator

[0089] 140…Second separator 150…Central tube

[0090] 210…First collector plate 211…First linear region

[0091] 212…Second linear region 213…First intersection region

[0092] 214…First welding area 215…Adhesive portion

[0093] 220…Second collector plate 221…Third linear region

[0094] 222… Fourth linear region 223… Second intersection region

[0095] 224…Second welding area 310…Tank shell

[0096] 311…Opening 320…Electrode Terminal

[0097] 330…Insulator 400…First probe unit

[0098] 410…First probe 500…Second probe unit

[0099] 510…Second probe

[0100] Industrial applicability

[0101] The method for inspecting the welding status of a battery according to an exemplary embodiment of the present disclosure can perform a comprehensive online inspection, thereby improving the quality of battery production and removing defective batteries in advance.

[0102] The method for inspecting the welding status of a battery according to an exemplary embodiment of the present disclosure can identify the welding quality within a short period of time.

Claims

1. A method for checking the welding state of a battery, wherein, The battery is a cylindrical battery including: a jelly-roll that is cylindrical and extends in a vertical direction in a case where a first current collector, a first separator, a second current collector, and a second separator are sequentially stacked and wound; a first current collector plate coupled to an upper end of the jelly-roll, wherein the first current collector is first welded to a lower surface of the first current collector plate; and a second current collector plate coupled to a lower end of the jelly-roll, wherein the second current collector is second welded to an upper surface of the second current collector plate, the method including: a first measurement step of measuring resistance by bringing a first probe unit into contact with an upper surface of the first current collector plate, wherein the first probe unit includes at least one pair of first probes including one first negative probe and one first positive probe, and different individual points are contacted such that a first welding area is interposed between the first negative probe and the first positive probe; a second measurement step of measuring resistance by bringing a second probe unit into contact with a lower surface of the second current collector plate, wherein the second probe unit includes at least one pair of second probes including one second negative probe and one second positive probe, and different individual points are contacted such that a second welding area is interposed between the second negative probe and the second positive probe; a first welding determination step of determining a state of the first welding based on resistance values measured in the first measurement step; and a second welding determination step of determining a state of the second welding based on resistance values measured in the second measurement step.

2. The method of claim 1, wherein, the first probe unit includes a plurality of first probes disposed in a plurality of pairs, and the second probe unit includes a plurality of second probes disposed in a plurality of pairs, and wherein, in the first measurement step, the plurality of first probes measure resistance values by contacting different individual points of the first current collector plate, and in the second measurement step, the plurality of second probes measure resistance values by contacting different individual points of the second current collector plate.

3. The method of claim 2, wherein, the first current collector plate is disposed in a cross shape in which a first linear area and a second linear area cross each other, and the second current collector plate is disposed in a cross shape in which a third linear area and a fourth linear area cross each other, wherein an area in which the first linear area and the second linear area overlap is defined as a first cross area, and an area in which the third linear area and the fourth linear area overlap is defined as a second cross area, wherein, in the first measurement step, at least one pair of first probes among the plurality of first probes measures a first resistance value by contacting the first linear area with the first cross area interposed therebetween, and at least another pair of first probes among the plurality of first probes measures a second resistance value by contacting the second linear area with the first cross area interposed therebetween, and wherein, in the second measurement step, at least one pair of second probes among the plurality of second probes measures a first resistance value by contacting the third linear area with the second cross area interposed therebetween, and at least another pair of second probes among the plurality of second probes measures a second resistance value by contacting the fourth linear area with the second cross area interposed therebetween. At least one pair of the second probes among the plurality of second probes measures a third resistance value by contacting the third linear region with the second crossing region interposed therebetween, and At least another pair of the second probes among the plurality of second probes measures a fourth resistance value by contacting the fourth linear region with the second crossing region interposed therebetween. 4.The method of claim 3, wherein, In the first welding determination step, a state of the first welding is determined based on the first resistance value and the second resistance value, and In the second welding determination step, a state of the second welding is determined based on the third resistance value and the third resistance value.

5. The method of claim 1, wherein, An arc-shaped adhesive portion is provided at an edge of the first current collector, wherein the cylindrical battery further includes: a can housing configured to accommodate the jelly-roll inside, the adhesive portion being third-welded to an inner circumferential surface of the can housing; and an electrode terminal fixed to a lower end of the can housing with an insulator interposed therebetween, the electrode terminal being fourth-welded to the second current collector plate, and wherein the method further includes, after the second welding determination step, a third measurement step of measuring a resistance value by bringing a probe into contact with the first current collector plate and bringing another probe into contact with an outer circumferential surface of the can housing; a fourth measurement step of measuring a resistance value by bringing a probe into contact with the second current collector plate and bringing another probe into contact with the electrode terminal; a third welding determination step of determining a state of the third welding based on the resistance value measured in the third measurement step; and a fourth welding determination step of determining a state of the fourth welding based on the resistance value measured in the fourth measurement step.

6. The method of claim 5, wherein, The resistance measurement in the first measurement step, the second measurement step, the third measurement step, and the fourth measurement step is performed by a four-wire low resistance direct current method. 7.A method for manufacturing a cylindrical battery, comprising: a step of forming a jelly-roll by winding a sequential stack of a first current collector, a first separator, a second current collector, and a second separator; a step of first-welding the first current collector and a first current collector plate at an upper end of the jelly-roll; a step of second-welding the second current collector and a second current collector plate at a lower end of the jelly-roll; a first welding determination step of measuring a resistance by bringing a first probe unit into contact with an upper surface of the first current collector plate, and determining a state of the first welding based on the measured resistance value, wherein the first probe unit includes at least one pair of first probes, the pair of first probes including one first negative electrode probe and one first positive electrode probe, and contacting different respective points such that a first welding region is interposed between the first negative electrode probe and the first positive electrode probe; and a second welding determination step of measuring a resistance by bringing a second probe unit into contact with a lower surface of the second current collector plate, and determining a state of the second welding based on the measured resistance value, wherein the second probe unit includes at least one pair of second probes, the pair of second probes including one second negative electrode probe and one second positive electrode probe, and contacting different respective points such that a second welding region is interposed between the second negative electrode probe and the second positive electrode probe. measuring resistance by bringing a second probe unit into contact with a lower surface of the second current collector plate, the second probe unit including at least one pair of second probes including one second negative probe and one second positive probe, and contacting different respective points such that a second weld region is interposed between the second negative probe and the second positive probe, and determining a state of the second weld based on the measured resistance value; a step of third welding the first current collector plate and the can body shell; a step of fourth welding the second current collector plate and the electrode terminal; a third weld determining step of measuring resistance by bringing a probe into contact with the first current collector plate and another probe into contact with an outer peripheral surface of the can body shell, and determining a state of the third weld based on the measured resistance value; a fourth weld determining step of measuring resistance by bringing a probe into contact with the second current collector plate and another probe into contact with the electrode terminal, and determining a state of the fourth weld based on the measured resistance value; and a step of injecting an electrolyte into the can body shell and sealing the can body shell. ​

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