Jig for measuring characteristics of battery cell for secondary battery and measuring device including the same

Abstract

To provide a jig for measuring the characteristics of battery cells for secondary batteries that reduces resistance obstructing the flow of currents and improves the distortion of the measured impedance of the battery cells.SOLUTION: A jig for measuring the characteristics of battery cells for secondary batteries according to the present disclosure comprises: a support table on which a battery cell including a cathode and an anode terminal is placed; a first and a second contact for the cathode contacted with the cathode terminal, and a first and a second contact for the anode contacted with the anode terminal; a first and a second current terminal for applying a current to the battery cell; a first and a second voltage terminal for measuring a voltage of the battery cell; an impedance measurement unit located on one side of the battery cell; and an elevating unit constituted to be capable of lifting and lowering the impedance measurement unit. At least one of the first and the second current terminals is located facing at least one of the first and the second voltage terminals.SELECTED DRAWING: Figure 4a

Description

[Technical Field]

[0001] The present disclosure relates to a battery cell characteristic measuring device, and to a device for measuring the impedance of a battery cell. [Background technology]

[0002] A rechargeable battery is a battery that can be repeatedly charged and discharged, unlike a primary battery. Small-capacity secondary batteries are used in small, portable electronic devices such as mobile phones, laptops, and camcorders. Large-capacity and high-density secondary batteries are used as motor drive power sources and for energy storage in hybrid and electric vehicles.

[0003] Such secondary batteries can be provided to consumers after undergoing characteristic tests to check the stability and performance of the battery cells. One example of such characteristic tests is an impedance test of the battery cells of the secondary battery.

[0004] When measuring the impedance of a battery cell, it is important to ensure that the measured impedance is not distorted due to increased inductance caused by the structure and arrangement of measurement equipment components (e.g., current lines, voltage lines).

[0005] The information disclosed above in the Background of the Invention section is intended to provide a better understanding of the background of the present invention and may include information that does not constitute prior art. Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention provides a battery cell characteristic measuring device that can minimize the influence of inductance when measuring the impedance of a battery cell.

[0007] However, the technical problems that the present invention aims to solve are not limited to the above-mentioned problems, and other problems not mentioned will be clearly understood by those skilled in the art from the description of the invention described below. [Means for solving the problem]

[0008] A battery cell characteristic measuring jig for a secondary battery according to one embodiment of the present invention includes a support base on which a battery cell including a terminal side on which a positive terminal and a negative terminal are arranged is provided, an impedance measuring unit that is detachably attached to the terminal side of the battery cell, and a lifting unit that is fixed to the support base, connected to the impedance measuring unit, and configured to raise and lower the impedance measuring unit relative to the terminal side of the battery cell.

[0009] The impedance measuring unit includes a positive electrode contact portion that comes into contact with the positive electrode terminal, a negative electrode contact portion that comes into contact with the negative electrode terminal, a first current terminal connected to the positive electrode contact portion and for applying current to the battery cell, a first voltage terminal connected to the positive electrode contact portion and for measuring the voltage of the battery cell, a second current terminal connected to the negative electrode contact portion and for applying current to the battery cell, and a second voltage terminal connected to the negative electrode contact portion and for measuring the voltage of the battery cell.

[0010] At least one of the first current terminal and the second current terminal is disposed opposite to at least one of the first voltage terminal and the second voltage terminal.

[0011] The impedance measuring unit may include a first body to which the first positive electrode contact portion, the second positive electrode contact portion, the first current terminal, and the first voltage terminal are coupled, and a second body to which the first negative electrode contact portion, the second negative electrode contact portion, the second current terminal, and the second voltage terminal are coupled, the second body being spaced apart from the first body and disposed adjacent to the first body.

[0012] The first current terminal and the first voltage terminal may be arranged on the first body in a non-overlapping manner on the same line.

[0013] The second current terminal and the second voltage terminal may be arranged on the second body in a non-overlapping manner on the same line.

[0014] The area of ​​the first positive electrode contact portion may be equal to or larger than the area of ​​the second positive electrode contact portion.

[0015] The area of ​​the first negative electrode contact portion may be equal to or larger than the area of ​​the second negative electrode contact portion.

[0016] The impedance measuring unit may include a single body to which the first positive electrode contact portion, the second positive electrode contact portion, the first current terminal, the first voltage terminal, the first negative electrode contact portion, the second negative electrode contact portion, the second current terminal, and the second voltage terminal are coupled.

[0017] The first current terminal and the first voltage terminal may be arranged on the single body in a non-overlapping manner on the same line.

[0018] The second current terminal and the second voltage terminal may be disposed between the first current terminal and the first voltage terminal, and an angle between the second current terminal and the second voltage terminal may be an acute angle.

[0019] The area of ​​the first positive electrode contact portion may be the same as or larger than the area of ​​the second positive electrode contact portion, and the area of ​​the first negative electrode contact portion may be the same as or larger than the area of ​​the second negative electrode contact portion.

[0020] A fixing frame for fixing the battery cell may be disposed on the support base.

[0021] The support base may include a bottom plate and a vertical plate extending from one side of the bottom plate, and the fixing frame may be disposed on the bottom plate.

[0022] The battery cells fixed to the fixing frame may be rectangular battery cells.

[0023] A support frame for supporting the battery cells may be disposed on the support base.

[0024] The support table may include a bottom plate and a vertical plate extending from one side of the bottom plate, and the support frame may be disposed on the bottom plate.

[0025] The battery cells fixed to the fixing frame may be cylindrical battery cells.

[0026] According to another embodiment of the present invention, an apparatus for measuring characteristics of a battery cell for a secondary battery includes a housing having a chamber in which the above-described measuring tool is received, and in which a current wire for applying a current to the first and second current terminals and a voltage wire for sensing the voltage of the battery cell are provided from the first and second voltage terminals.

[0027] According to the embodiment of the present invention, the current terminals and voltage terminals of the measurement jig are arranged so as not to overlap with each other, thereby making it possible to reduce inductance when measuring the impedance of a battery cell.

[0028] This reduces the resistance that impedes the flow of current and improves the distortion of the measured battery cell impedance. [Brief explanation of the drawings]

[0029] The drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention described below, serve to further understand the technical concept of the present invention, so the present invention should not be interpreted as being limited only to the matters depicted in these drawings. [Figure 1] 1 is a perspective view that schematically illustrates a battery cell characteristic measuring device for a secondary battery according to an embodiment. [Figure 2] FIG. 1 is a perspective view schematically showing a measuring jig according to a first embodiment. [Figure 3] FIG. 1 is a perspective view showing a battery cell according to a first embodiment. [Figure 4a]2 is a diagram illustrating an impedance measuring unit according to the first embodiment. [Figure 4b] 2 is a diagram illustrating an impedance measuring unit according to the first embodiment. [Figure 4c] 2 is a diagram illustrating an impedance measuring unit according to the first embodiment. [Figure 4d] 2 is a diagram illustrating an impedance measuring unit according to the first embodiment. [Figure 5a] 4 is a graph shown to explain the effect of the measuring jig according to the first embodiment. [Figure 5b] 4 is a graph shown to explain the effect of the measuring jig according to the first embodiment. [Figure 6] FIG. 10 is a perspective view schematically showing a measuring jig according to a second embodiment. [Figure 7] FIG. 10 is a perspective view showing a battery cell according to a second embodiment. [Figure 8a] 10 is a diagram illustrating an impedance measuring unit according to a second embodiment. [Figure 8b] 10 is a diagram illustrating an impedance measuring unit according to a second embodiment. [Figure 8c] 10 is a diagram illustrating an impedance measuring unit according to a second embodiment. [Figure 8d] 10 is a diagram illustrating an impedance measuring unit according to a second embodiment. [Figure 9a] 10 is a graph shown to explain the effect of the measuring jig according to the second example. [Figure 9b] 10 is a graph shown to explain the effect of the measuring jig according to the second example. DETAILED DESCRIPTION OF THE INVENTION

[0030] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms and words used in this specification and claims should not be construed as being limited to their ordinary or dictionary meanings, but should be construed as meanings and concepts that are consistent with the technical concept of the present invention, based on the principle that the inventor can appropriately define the concept of the term to best describe his or her invention. Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are only some of the most preferred embodiments of the present invention and do not fully represent the technical concept of the present invention, and therefore various equivalents and modifications may exist as of the time of filing this application.

[0031] Also, as used in this specification, "comprise" and / or "comprising" specify the presence of stated shapes, numbers, steps, operations, members, elements and / or groups thereof, but do not exclude the presence or addition of one or more other shapes, numbers, operations, members, elements and / or groups.

[0032] In order to facilitate understanding of the invention, the accompanying drawings may not be drawn to scale, and the dimensions of some components may be exaggerated. In addition, the same reference numerals may be used to refer to the same components in different embodiments.

[0033] A statement that two comparison objects are "the same" means that they are "substantially the same." Therefore, "substantially the same" can include cases where there is a deviation that is considered to be a low level in the art, for example, a deviation within 5%. Furthermore, uniformity of some parameter in a given region can mean uniformity from an average perspective.

[0034] Although terms such as "first" and "second" are used to describe various components, it is understood that these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless otherwise specified, a first component may also be a second component.

[0035] Throughout the specification, unless specifically stated to the contrary, each element may be singular or plural.

[0036] When any structure is placed "on top (or bottom)" of a component or "above (or below)" a component, it can mean not only that the structure is placed in contact with the upper surface (or lower surface) of the component, but also that there may be another structure interposed between the component and any structure placed above (or below) the component.

[0037] Furthermore, when a component is described as being "on," "connected to," or "coupled to" another component, it should be understood that the components may be directly coupled or connected to each other, but that other components may be "intervening" between the components, or that each component may be "coupled," "coupled," or "connected" via other components.

[0038] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. Also, the use of "may" when describing embodiments of the present disclosure refers to "one or more embodiments of the present disclosure." The use of phrases such as "one or more" and "one or more" before a list of elements modifies the list of elements as a whole, and not individual elements of the list.

[0039] Throughout the specification, "A and / or B" means A, B, or A and B, unless specifically stated to the contrary, and "C through D" means at least C and at most D, unless specifically stated to the contrary.

[0040] When syntax such as "at least one of A, B and C," "at least one of A, B or C," "at least one selected from the group of A, B and C," or "at least one selected from A, B and C" is used to specify a list of elements A, B, and C, the syntax can refer to any and all suitable combinations.

[0041] The term "use" may be considered synonymous with the term "utilize." As used herein, "substantially," "about," and similar terms may be used as terms of approximation rather than terms of degree, and are intended to account for inherent variations in measured or calculated values ​​that one of ordinary skill in the art would recognize.

[0042] In this specification, terms such as first, second, and third may be used to describe various elements, components, regions, layers, and / or sections, but these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms are used to distinguish one element, component, region, drawing layer, or cross section from another element, component, region, drawing layer, or cross section. Thus, a first element, component, region, tier, or section discussed below could be named a second element, component, region, tier, or section without departing from the teachings of the illustrative embodiments.

[0043] For ease of description, spatially relative terms such as "beneath," "below," "lower," "above," "upper," etc. may be used herein to describe the relationship of one element or feature to another element or feature as illustrated in the drawings. Spatially relative positions will be understood to encompass different orientations of the device during use or operation other than the orientation depicted in the figures. For example, if the device in the drawings is inverted, elements described as "beneath" or "below" would be understood to be "above" or "upper" of the other elements. Thus, the term "below" can encompass both the above and below orientations.

[0044] The terminology used herein is for the purpose of describing embodiments of the present disclosure and is not intended to be limiting of the present disclosure.

[0045] In the exemplary embodiments of the prismatic and pouch-type secondary batteries according to the embodiments of the present disclosure, one of the prismatic and pouch-type secondary batteries is selected, and the selected battery is described as having a general structure. In the case of a generally applicable technology, the general structure of the prismatic and pouch-type secondary battery is described.

[0046] FIG. 1 is a perspective view that schematically shows a battery cell characteristic measuring device for a secondary battery (hereinafter referred to as a measuring device for convenience) according to an embodiment of the present invention.

[0047] The measurement device 1 is configured to measure the characteristics of a secondary battery through a battery cell characteristic measuring jig 3 for a secondary battery (hereinafter referred to as the measuring jig for convenience) placed in a measurement chamber 10. In this embodiment, the measuring jig 3 is configured to measure the impedance of the battery cell.

[0048] The measurement chamber 10 can be provided in a plurality of units by a frame 14 disposed in the main body 12 of the measurement device 1 and a separation plate 16 connected to the frame 14 .

[0049] In addition, the main body 12 of the measuring device 1 is provided with an operation panel 18 for electrical operations such as adjusting the temperature and humidity inside the measurement chamber 10 and applying current to the battery cell 5 provided in the measuring jig 3 to measure the impedance of the battery cell 5.

[0050] First Example Fig. 2 is a perspective view that schematically shows the measuring jig according to Example 1. As shown in Fig. 2, the measuring jig 3a of Example 1 includes a support base 30a on which the battery cell 5a is placed.

[0051] In the first embodiment, the battery cell 5a may be a prismatic battery cell, as shown in Fig. 3. The battery cell 5a has a terminal side 54a on which a positive terminal 50a and a negative terminal 52a are disposed. Here, the terminal side 54a may refer to the side of a prismatic battery cell on which the positive terminal 50a and the negative terminal 52a are disposed. The terminal side 54a is the side of a cap plate 58a that is coupled to a case 56a of the battery cell 5a.

[0052] Referring again to FIG. 2, the battery cells 5a can undergo impedance measurement while inserted into the fixing frames 32a fixed to the support base 30a. The support base 30a includes a bottom plate 300a on which the fixing frames 32a are disposed and a vertical plate 302a extending from one edge of the bottom plate 300a. The number of fixing frames 32a disposed on the support base 30a, in other words, the number of battery cells 5a, can be appropriately adjusted. In the first embodiment, two fixing frames 32a are provided, one for each battery cell 5a, but this does not limit the structure of the measurement jig 3a.

[0053] An elevation unit 36a is fixedly disposed on the vertical plate 302a and can raise and lower an impedance measuring unit 34a configured to measure the impedance of the battery cell 5a while being attached to and detached from the terminal side 54a of the battery cell 5a.

[0054] The impedance measuring section 34a includes a positive electrode contact section 340a that comes into contact with the positive electrode terminal 50a, and a negative electrode contact section 342a that comes into contact with the negative electrode terminal 52a.

[0055] 4a to 4d are views illustrating the positive electrode contact part 340a. Referring to FIGS. 4a to 4d, the positive electrode contact part 340a includes a first body 3400a having a generally rectangular parallelepiped shape. The first body 3400a includes a lower body 3402a and an upper body 3404a that are detachably connectable to each other. A first positive electrode contact part 3406a and a second positive electrode contact part 3408a that respectively contact the positive electrode terminal 50a are provided at an arbitrary interval on the lower body 3402a. The first positive electrode contact part 3406a and the second positive electrode contact part 3408a are provided on the lower body 3402a with their tips exposed to the outside of the lower body 3402a and are movable up and down within the lower body 3402a.

[0056] A first current terminal 3410a and a first voltage terminal 3412a are connected to the first positive electrode contact portion 3406a and the second positive electrode contact portion 3408a, respectively. The first current terminal 3410a is connected to the first positive electrode contact portion 3406a so that current (AC) is applied to the battery cell 5a. The first voltage terminal 3412a is connected to the second positive electrode contact portion 3408a so that voltage from the battery cell 5a can be measured.

[0057] According to the first embodiment, the first current terminal 3410a and the first voltage terminal 3412a each include rod-shaped lead portions 3414a and 3416a arranged opposite each other, and cylindrical connecting portions 3418a and 3420a connected vertically to one end of the lead portions 3414a and 3416a.

[0058] In the first embodiment, the lead portions 3414a and 3416a are arranged parallel to each other on a non-collinear line. That is, the first positive electrode contact portion 3406a and the second positive electrode contact portion 3408a are arranged approximately at the center of the first body 3400a, and the lead portions 3414a and 3416a are arranged on the first body 3400a so that their respective connection portions 3418a and 3420a face each other. As a result, the angle between the lead portions 3414a and 3416a, in other words, the angle between the first current terminal 3410a and the first voltage terminal 3412a, is considered to be 180°. This arrangement of the first current terminal 3410a and the first voltage terminal 3412a minimizes the overlapping area between the terminals, reducing the increase in inductance due to a magnetic field and effectively preventing distortion of the measured impedance.

[0059] According to the first embodiment, the leads 3414a, 3416a are non-collinear, as described above, but according to other embodiments, the leads can be collinear.

[0060] Furthermore, according to the first embodiment, the lead portions 3414a, 3416a are arranged at an angle of 180° as described above, but they may also be arranged at an angle selected between 90° and 180°.

[0061] A current line 38a for applying a current to the first current terminal 3410a and a voltage line 40a for sensing the voltage of the battery cell 5a from the first voltage terminal 3412a are connected to the connection parts 3418a and 3420a, respectively.

[0062] A portion of the lead portions 3414a, 3416a including the connection portions 3418a, 3420a is exposed outside the first body 3400a, and the remaining portion of the lead portions 3414a, 3416a including the first positive electrode contact portion 3406a and the second positive electrode contact portion 3408a connected to the other end of the lead portions 3414a, 3416a is arranged within the first body 3400a.

[0063] At the other ends of the lead portions 3414a, 3416a to which the first positive electrode contact portion 3406a and the second positive electrode contact portion 3408a are connected, springs 3422a, 3424a are installed facing the first positive electrode contact portion 3406a and the second positive electrode contact portion 3408a. These springs 3422a, 3424a enable the first positive electrode contact portion 3406a and the second positive electrode contact portion 3408a to elastically contact the positive electrode terminal 50a by the force exerted by the lifting portion described below.

[0064] In the first embodiment, the area of ​​the first positive electrode contact portion 3406a may be equal to or larger than the area of ​​the second positive electrode contact portion 3408a in order to reduce the contact resistance of the current terminal and reduce heat generation when actual current flows.

[0065] Meanwhile, the negative electrode contact part 342a is configured similarly to the positive electrode contact part 340a. That is, the negative electrode contact part 342a also includes a second body (lower body / upper body), a first negative electrode contact part, a second negative electrode contact part, a second current terminal (lead part / connection part), a second voltage terminal (lead part / connection part), and a spring. A detailed description thereof will be substituted for the description of the positive electrode contact part 340a described above.

[0066] The impedance measuring unit 34a configured in this manner is connected to a lifting unit 36a fixedly installed on the vertical plate 302a of the support base 30a so as to be movable up and down.

[0067] As can be seen from FIG. 2, in the first embodiment, the lifting unit 36a is configured to lift and lower the positive electrode contact portion 340a and the negative electrode contact portion 342a using a hinge system.

[0068] For this purpose, the lifting unit 36a includes a lower pressing portion 360a connected to each of the positive electrode contact portion 340a and the negative electrode contact portion 342a, an upper pressing portion 366a connected to the lifting shaft 364a, and a handle portion 370a hinged to the lifting shaft 364a via a hinge pin 368a, as well as a lower pressing portion 360a elastically connected to the lower pressing portion 360a via a spring 362a interposed between the lower pressing portion 360a and the upper pressing portion 366a connected to the lifting shaft 364a.

[0069] The positive electrode contact portion 340a and the negative electrode contact portion 342a can be connected (e.g., screwed) to the lower pressing portion 360a at any interval, for example, an interval corresponding to the interval between the positive electrode terminal 50a and the negative electrode terminal 52a of the battery cell 5a, and the lifting shaft 364a can be coupled to a mounting base 372a fixed to the vertical plate 302a so as to be guided by the mounting base 372a.

[0070] 2, when the user presses the handle 370a downward to position it so that it remains horizontal, the lifting shaft 364a descends, and the upper pressing portion 366a, the lower pressing portion 360a, the positive electrode contact portion 340a, and the negative electrode contact portion 342a also descend accordingly. As a result, the first positive electrode contact portion 3406a and the second positive electrode contact portion 3408a come into contact with the positive electrode terminal 50a of the battery cell 5a, and the first negative electrode contact portion and the second negative electrode contact portion come into contact with the negative electrode terminal 50b of the battery cell 5a. In this state, a current is applied to the first current terminal 3410a and the second current terminal, and voltage is sensed via the first voltage terminal 3412a and the second voltage terminal, thereby measuring the impedance of the battery cell 5a. At this time, the first terminal for current 3410a and the second terminal for current are arranged substantially in a line so as not to overlap each other, and the first terminal for voltage 3412a and the second terminal for voltage are also arranged substantially in a line so as not to overlap each other, so that an increase in inductance due to a magnetic field can be reduced and the impedance of the battery cell 5a can be measured without distortion.

[0071] When the impedance measurement is complete, the user lifts the handle portion 370a from bottom to top (switching from the vertical state shown in FIG. 2) so that the first positive electrode contact portion 3406a and the second positive electrode contact portion 3408a are separated from the positive electrode terminal 50a of the battery cell 5a, and the first negative electrode contact portion and the second negative electrode contact portion are separated from the negative electrode terminal 52a of the battery cell 5a. Then, the battery cell for which the impedance measurement has been completed is replaced with a new battery cell for which impedance measurement is to be performed.

[0072] 5a and 5b are graphs showing the results of measuring the charge exchange resistance (Rct) and inductance of a battery cell using the measurement jig according to the first embodiment and the measurement jig according to the comparative example, respectively. Unlike the first embodiment, the measurement jig according to the comparative example has the first current terminal, second current terminal, first voltage terminal, and second voltage terminal for the positive and negative terminals of the battery cell overlapping each other and configured as a single unit. The battery cells measured using each measurement jig are the prismatic battery cells shown in FIG. 3.

[0073] As can be seen from Figures 5a and 5b, when measuring the impedance of a battery cell using the measurement jig of the first embodiment, the improved current terminals and voltage terminals reduce inductance, allowing impedance to be measured without (or with improved) distortion of the charge exchange resistance (Rct).

[0074] Second Example Fig. 6 is a perspective view that schematically shows a measuring jig according to Example 2. As shown in Fig. 6, a measuring jig 7a of Example 2 includes a support base 70a on which a battery cell 9a is placed.

[0075] In the second embodiment, the battery cell 9a may be a cylindrical battery cell, as shown in FIG. 7. The battery cell 9a has a terminal side 94a on which a positive terminal 90a and a negative terminal 92a are disposed. Here, the terminal side 94a may refer to the side of a cylindrical battery cell on which the positive terminal 90a and the negative terminal 92a are disposed. The terminal side 94a may be the side of a cap plate 98a coupled to a case 96a of the battery cell 9a. The positive terminal 90a may have a rivet structure coupled to the cap plate 98a, which is, for example, the negative terminal 92a, so as to be electrically isolated from the case 96a. The cap plate 98a may be coupled to the case 96a so as to be electrically connected to the case 96a. The positive terminal 90a is electrically connected to the positive electrode of an electrode assembly disposed within the case 96a, and the negative terminal 92a is electrically connected to the negative electrode of the electrode assembly.

[0076] Referring again to FIG. 6, the battery cell 9a can undergo impedance measurement while being placed on a support frame 72a fixedly installed on a support stand 70a. The support stand 70a includes a bottom plate 700a on which the support frame 72a is disposed and a vertical plate 702a extending from one side edge of the bottom plate 700a. The number of support frames 72a disposed on the support stand 70a, in other words, the number of battery cells 9a, can be appropriately adjusted. In the second embodiment, two support frames 72a are provided with a battery cell 9a, but this does not limit the structure of the measurement jig 7a.

[0077] An elevation unit 76a is fixedly disposed on the vertical plate 702a and can raise and lower an impedance measuring unit 74a configured to measure the impedance of the battery cell 9a while being attached to and detached from the terminal side 94a of the battery cell 9a.

[0078] The impedance measuring section 74a includes a positive electrode contact section 740a that comes into contact with the positive electrode terminal 90a, and a negative electrode contact section 742a that comes into contact with the negative electrode terminal 92a.

[0079] 8a to 8d are views illustrating the positive electrode contact portion 340a and the negative electrode contact portion 742a. ​​Referring to FIGS. 8a to 8d, the impedance measuring unit 74a includes a substantially cylindrical single body 744a. The single body 744a includes a lower body 7400a and an upper body 7402a that are detachably coupled to each other. A first positive electrode contact portion 7406a and a second positive electrode contact portion 7408a, which respectively contact the positive electrode terminal 90a, are installed at an arbitrary interval on the lower body 7400a. The first positive electrode contact portion 7406a and the second positive electrode contact portion 7408a are installed in the lower body 7400a with their tips exposed to the outside of the lower body 7400a and are movable up and down within the lower body 7400a.

[0080] A first current terminal 7410a and a first voltage terminal 7412a are connected to the first positive electrode contact portion 7406a and the second positive electrode contact portion 7408a, respectively. The first current terminal 7410a is connected to the first positive electrode contact portion 7406a so that current (AC) is applied to the battery cell 9a. The first voltage terminal 7412a is connected to the second positive electrode contact portion 7408a so that voltage is measured from the battery cell 9a. According to the second embodiment, the first current terminal 7410a and the first voltage terminal 7412a include rod-shaped lead portions 7414a and 7416a arranged opposite each other and cylindrical connecting portions 7418a and 7420a connected vertically to one ends of the lead portions 7414a and 7416a, respectively.

[0081] In the second embodiment, the lead portions 7414a and 7416a are arranged parallel to one another. That is, the first positive electrode contact portion 7406a and the second positive electrode contact portion 7408a are arranged approximately at the center of the single body 744a, and the lead portions 7414a and 7416a are arranged on the single body 744a so that their respective connection portions 7418a and 7420a face each other. As a result, the angle between the lead portions 7414a and 7416a, in other words, the angle between the first current terminal 7410a and the first voltage terminal 7412a, is considered to be 180°. This arrangement of the first current terminal 7410a and the first voltage terminal 7412a minimizes the overlapping area between the terminals, reducing the increase in inductance due to a magnetic field and effectively preventing distortion of the measured impedance.

[0082] In the second embodiment, both leads 7414a, 7416a are collinear, as described above, although in other embodiments, the leads may be non-collinear.

[0083] Furthermore, according to the second embodiment, the lead portions 7414a and 7416a are arranged at an angle of 180° as described above, but they may also be arranged at an angle selected between 90° and 180°.

[0084] A current line (not shown) for applying current to the first current terminal 7410a and a voltage line (not shown) for sensing the voltage of the battery cell 9a from the first voltage terminal 7412a are connected to the connection portions 7418a and 7420a, respectively.

[0085] A portion of the lead portions 7414a, 7416a including the connection portions 7418a, 7420a is exposed outside the single body 744a, and the remaining portion of the lead portions 7414a, 7416a including the first positive electrode contact portion 7406a and the second positive electrode contact portion 7408a connected to the other end of the lead portions 7414a, 7416a is positioned within the first body 3400a.

[0086] At the other ends of the lead portions 7414a, 7416a to which the first positive electrode contact portion 7406a and the second positive electrode contact portion 7408a are connected, springs 7422a, 7424a are installed facing the first positive electrode contact portion 7406a and the second positive electrode contact portion 7408a. These springs 7422a, 7424a enable the first positive electrode contact portion 7406a and the second positive electrode contact portion 7408a to elastically contact the positive electrode terminal 90a by the force exerted by the lifting portion described below.

[0087] In the second embodiment, the area of ​​the first positive electrode contact portion 7406a may be equal to or larger than the area of ​​the second positive electrode contact portion 7408a in order to reduce the contact resistance of the current terminal and reduce heat generation when actual current flows.

[0088] Meanwhile, the negative electrode contact portion 742a is configured similarly to the positive electrode contact portion 740a. That is, the negative electrode contact portion 742a also includes a first negative electrode contact portion 7426a, a second negative electrode contact portion 7428a, a second current terminal 7430a (lead portion 7432a / connection portion 7434a), a second voltage terminal 7436a (lead portion 7438a / connection portion 7440a), and springs 7442a and 7444a. A detailed description thereof will be provided in the description of the positive electrode contact portion 340a described above.

[0089] However, the negative electrode contact portion 742a is installed on the single body 744a together with the positive electrode contact portion 740a, but the second current terminal 7430a and the second voltage terminal 7436a are arranged between the first current terminal 7410a and the first voltage terminal 7412a, and the angle between them is an acute angle (e.g., 10° to 80°).

[0090] The impedance measuring unit 74a configured in this manner is connected to a lifting unit 76a fixedly installed on the vertical plate 702a of the support stand 70a so as to be movable up and down.

[0091] As can be seen from FIG. 6, in the second embodiment, the lifting unit 76a is configured to lift and lower the positive electrode contact portion 740a and the negative electrode contact portion 742a by a screw method.

[0092] For this purpose, the lifting unit 76a includes a pressing unit 760a connected (e.g., screwed) to each of the positive electrode contact unit 740a and the negative electrode contact unit 742a, a lifting shaft 762a connected to the pressing unit 760a and provided with a screw thread, a mounting base 764a fixed to the vertical plate 702a and connected to the lifting shaft 762a so that the lifting shaft 762a can be lifted and guided by the screw method, and a handle unit 766a connected to one end of the lifting shaft 762a.

[0093] As a result, when the user rotates the handle portion 766a clockwise, the lifting shaft 762a descends, and in conjunction with this, the pressing portion 760a, the positive electrode contact portion 740a, and the negative electrode contact portion 742a also descend. As a result, the first positive electrode contact portion 7406a and the second positive electrode contact portion 7408a come into contact with the positive electrode terminal 90a of the battery cell 9a, and the first negative electrode contact portion 7426a and the second negative electrode contact portion 7428a come into contact with the negative electrode terminal 92a of the battery cell 9a. In this state, a current is applied to the first current terminal 7410a and the second current terminal 7430a, and voltage is sensed via the first voltage terminal 7412a and the second voltage terminal 7436a, allowing the impedance of the battery cell 9a to be measured. In this case, the first current terminal 7410a and the first voltage terminal 7412a are arranged substantially in a straight line so as not to overlap each other, and the second current terminal 7430a and the second voltage terminal 7436a are also arranged at an acute angle so as not to overlap each other, so that an increase in inductance due to a magnetic field can be reduced and the impedance of the battery cell 9a can be measured without distortion.

[0094] When the impedance measurement is complete, the user can rotate the handle portion 766a counterclockwise to separate the first positive electrode contact portion 7406a and the second positive electrode contact portion 7408a from the positive electrode terminal 90a of the battery cell 9a and to separate the first negative electrode contact portion 7426a and the second negative electrode contact portion 7428a from the negative electrode terminal 92a of the battery cell 9a. The battery cell for which the impedance measurement has been completed is then replaced with a new battery cell for which impedance measurement is to be performed.

[0095] 9a and 9b are graphs showing the results of measuring the charge exchange resistance (Rct) and inductance of a battery cell using the measurement jig according to the second embodiment and the measurement jig according to the comparative example, respectively. The measurement jig according to the comparative example differs from the second embodiment in that the first current terminal, second current terminal, first voltage terminal, and second voltage terminal for the positive and negative terminals of the battery cell are stacked together and configured as a single unit. The battery cells measured using each measurement jig are the cylindrical battery cells shown in FIG. 7.

[0096] As can be seen from Figures 9a and 9b, when measuring the impedance of a battery cell using the measurement jig of the second embodiment, the improved current and voltage terminals reduce inductance, allowing the impedance to be measured without (or with improved) distortion of the charge exchange resistance (Rct).

[0097] Although the present invention has been described above using limited examples and drawings, the present invention is not limited thereto, and it goes without saying that various modifications and variations can be made by a person having ordinary skill in the art to which the present invention pertains within the technical spirit of the present invention and the equivalent scope of the claims set forth below. [Explanation of symbols]

[0098] 3a, 7a: Measuring jig 5a, 9a: Battery cells 30a, 70a: Support stand 3406a, 7406a: 1st positive electrode contact part 3408a, 7408a: Contact part for second positive electrode 7426a: First negative electrode contact part 7428a: Contact part for second negative electrode 3410a, 7410a: 1st terminal for current 7430a: 2nd terminal for current 3412a, 7412a: First terminal for voltage 7436a: Second terminal for voltage 34a, 74a: Impedance measurement section 36a, 76a: Lifting section

Claims

1. a support base on which a battery cell is provided, the support base including a terminal side on which a positive terminal and a negative terminal are disposed; an impedance measuring unit that is detachable from the terminal side of the battery cell, and that includes a first positive electrode contact portion and a second positive electrode contact portion that are in contact with the positive electrode terminal, a first negative electrode contact portion and a second negative electrode contact portion that are in contact with the negative electrode terminal, a first current terminal that is connected to the first positive electrode contact portion and is used to apply a current to the battery cell, a first voltage terminal that is connected to the second positive electrode contact portion and is used to measure the voltage of the battery cell, a second current terminal that is connected to the first negative electrode contact portion and is used to apply a current to the battery cell, and a second voltage terminal that is connected to the second negative electrode contact portion and is used to measure the voltage of the battery cell; a lifting unit fixed to the support base, connected to the impedance measurement unit, and configured to lift and lower the impedance measurement unit relative to the terminal side of the battery cell; Including, At least one of the first current terminal and the second current terminal is disposed opposite at least one of the first voltage terminal and the second voltage terminal.

2. The impedance measurement unit a first body to which the first positive electrode contact portion, the second positive electrode contact portion, the first current terminal, and the first voltage terminal are coupled; a second body to which the first negative electrode contact portion, the second negative electrode contact portion, the second current terminal, and the second voltage terminal are coupled, the second body being spaced apart from the first body and disposed adjacent to the first body; The battery cell characteristic measuring jig for a secondary battery according to claim 1 , comprising:

3. The battery cell characteristic measuring jig for a secondary battery according to claim 2 , wherein the first current terminal and the first voltage terminal are arranged on the first body in a non-overlapping manner on the same line.

4. The battery cell characteristic measuring jig for a secondary battery according to claim 2 , wherein the second current terminal and the second voltage terminal are arranged on the second body in a non-overlapping manner on the same line.

5. 3. The battery cell characteristic measuring jig for a secondary battery according to claim 2, wherein an area of ​​the first positive electrode contact portion is equal to or larger than an area of ​​the second positive electrode contact portion.

6. 3. The battery cell characteristic measuring jig for a secondary battery according to claim 2, wherein an area of ​​the first negative electrode contact portion is equal to or larger than an area of ​​the second negative electrode contact portion.

7. The impedance measurement unit 2. The battery cell characteristic measuring jig for a secondary battery according to claim 1, comprising a single body to which the first positive electrode contact portion, the second positive electrode contact portion, the first current terminal, the first voltage terminal, the first negative electrode contact portion, the second negative electrode contact portion, the second current terminal, and the second voltage terminal are coupled.

8. The battery cell characteristic measuring jig for a secondary battery according to claim 7 , wherein the first current terminal and the first voltage terminal are arranged on the single body in a non-overlapping manner on the same line.

9. 9. The battery cell characteristic measuring jig for a secondary battery according to claim 8, wherein the second current terminal and the second voltage terminal are disposed between the first current terminal and the first voltage terminal, and an angle between the second current terminal and the second voltage terminal forms an acute angle.

10. 8. The battery cell characteristic measuring jig for a secondary battery according to claim 7, wherein an area of ​​the first positive electrode contact portion is equal to or larger than an area of ​​the second negative electrode contact portion, and an area of ​​the first negative electrode contact portion is equal to or larger than an area of ​​the second negative electrode contact portion.

11. The battery cell characteristic measuring jig for a secondary battery according to claim 1 , wherein a fixing frame for fixing the battery cell is disposed on the support base.

12. The battery cell characteristic measuring jig for a secondary battery according to claim 11 , wherein the support base includes a bottom plate and a vertical plate extending from one side of the bottom plate, and the fixing frame is disposed on the bottom plate.

13. The battery cell characteristic measuring jig for a secondary battery according to claim 12 , wherein the battery cells fixed to the fixing frame are rectangular.

14. The battery cell characteristic measuring jig for a secondary battery according to claim 1 , wherein a support frame for supporting the battery cell is disposed on the support base.

15. The battery cell characteristic measuring fixture of claim 14 , wherein the support table includes a bottom plate and a vertical plate extending from one side of the bottom plate, and the support frame is disposed on the bottom plate.

16. The battery cell characteristic measuring jig for a secondary battery according to claim 15 , wherein the battery cell supported by the support frame is cylindrical.

17. 17. A device for measuring characteristics of a battery cell for a secondary battery, comprising: a housing having a chamber in which the measuring jig according to any one of claims 1 to 16 is received, and in which a current wire for applying a current to the first current terminal and the second current terminal, and a voltage wire for sensing a voltage of the battery cell from the first voltage terminal and the second voltage terminal are provided.

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