Battery cell electrical parameter measurement device, measurement system, and measurement method

Abstract

Apparatus 1 for measuring the electrical parameters of a battery cell, particularly the insulation voltage, includes at least one probe 3 including a conductor 5 configured to be electrically coupled to a voltage sensor; the conductor 5 has an arc-shaped contact surface 51 configured to engage with the battery cell to be measured; and the apparatus also includes a biasing member 7 configured to elastically mount the conductor 5 in a first direction F.

Description

Technical Field

[0001] The present invention relates to an apparatus for measuring at least one electrical parameter, particularly the insulation voltage, of a battery cell, especially a pouch-type battery cell. The present invention also relates to a system including two or more such apparatuses. And the present invention relates to a method for measuring at least one electrical parameter, particularly the insulation voltage, of a pouch-type battery cell using one or more apparatuses according to the present invention.

Background Art

[0002] In modern society, with the popularization of portable devices such as mobile phones, notebook computers, camcorders, and digital cameras, the development of battery technology has very important significance. In addition, rechargeable secondary batteries have become an essential power source for electric vehicles (EVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (P-HEVs), etc. as an attempt to solve air pollution and carbon dioxide emissions caused by existing internal combustion engine vehicles using fossil fuels. Therefore, the need to improve secondary batteries is increasing.

[0003] Currently commercialized secondary batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries, and lithium secondary batteries. Among these, lithium secondary batteries have attracted attention due to various advantages such as almost no memory effect compared to nickel-based secondary batteries, being freely chargeable and dischargeable, having a very low self-discharge rate, and a high energy density.

[0004] Secondary batteries can be classified into cylindrical batteries in which an electrode assembly is mounted in a cylindrical metal can, prismatic batteries in which an electrode assembly is mounted in a prismatic metal can, and pouch-type batteries according to the shape of the battery case. A pouch-type secondary battery generally houses an electrode assembly having a structure in which electrodes and separator membranes are alternately arranged in a case in the form of a pouch made of a laminated aluminum sheet.

[0005] A secondary battery exhibiting leakage, short circuits, or electrical connections between components that should be isolated from each other is considered to be of reduced function and must be identified as being excluded from further use.

[0006] Battery cell inspection equipment and methods for measuring the electrical characteristics, particularly the insulation voltage, of pouch-type battery cells are described in KR 2023 0033529 A or KR 2020 0050697 A. [Overview of the project] [Problems that the invention aims to solve]

[0007] The object of the present invention is to provide apparatus, systems, and methods that can reliably and continuously detect defective batteries, particularly pouch-type batteries, overcoming the shortcomings of the prior art. In particular, the object of the present invention is to provide methods, systems, and apparatus comprising a reliable and durable probe that can be used without damaging pouch-type batteries and with little or no physical degradation. It may also be an object to provide methods, systems, and / or apparatus having a probe that can measure a large number of batteries in a short time with little or no risk of damaging the battery under test and the apparatus itself. Preferably, the system or apparatus according to the present invention is particularly easy to inspect and maintain, and preferably easy to assemble and disassemble. [Means for solving the problem]

[0008] This provides an apparatus for measuring at least one electrical parameter, in particular the insulation voltage, of a battery cell, especially a pouch-type battery cell. The apparatus is not only suitable for measuring the insulation voltage of a pouch-type battery cell, but may be particularly preferably configured for that purpose. The apparatus according to the present invention includes at least one probe. The probe includes a conductor and a biasing member. The conductor is configured to be electrically coupled to a current and / or voltage sensor. It may be particularly preferable that the conductor be electrically coupled to a voltage sensor in order to measure a voltage, in particular the insulation voltage, between the contact point of the probe and at least one reference point. The reference point may correspond to a ground level and / or a reference measurement at the first and / or second electrodes of the pouch-type battery in question. Alternatively or additionally, the reference point may correspond to a second or additional measurement made by a different apparatus along another edge, for example, at a location in the same pouch-type battery cell (the battery cell being measured) that is separated from the location contacted by the conductor.

[0009] The conductor has an arc-shaped contact surface configured to engage with the battery cell to be measured. The arc-shaped contact surface may be concave, and preferably convex. The arc-shaped contact surface can be formed as a continuous surface in the arc direction (along the circumference) and in the (axial) direction perpendicular to the arc direction (along the circumference) and radial direction. The continuous arc-shaped contact surface may have an axial width of 5 mm or more, particularly 10 mm or more, and / or a circumferential length of 20 mm or more. The arc-shaped contact surface may be configured to have a radius of curvature of preferably 5 mm to 5000 mm, particularly 10 mm to 1000 mm. The radius of curvature may be particularly 12 mm or more, preferably 15 mm or more, and more preferably 20 mm or more. The radius of curvature may be particularly 500 mm or less, preferably 250 mm or less, and more preferably 100 mm or less.

[0010] The biasing member is configured to elastically mount the conductor in a first direction. The conductor is mounted by the biasing member so as to be able to move forward and backward in a first direction. The conductor can move forward and backward in a first direction partially or entirely at the conductor portion that embodies the contact surface using the elasticity of the biasing member. For example, the conductor can move backward in a first direction by deformation of the biasing member, e.g., compression and / or deflection, when it is subjected to increased resistance due to engagement with the target battery cell, particularly the target pouch-type battery cell. Alternatively or additionally, the conductor can move forward in a first direction under the influence of deformation of the biasing member. For example, this occurs when the probe is released from the target battery cell, particularly the target pouch-type battery cell, and the biasing member returns from a deformed state to a relaxed state. In particular, the arc-shaped contact surface may have a width of 5 mm or more, especially 10 mm or more, preferably 20 mm or more, in the direction intersecting the first direction and / or the direction intersecting the radial direction of curvature. The width of the arc-shaped contact surface may be particularly 100 mm or less, preferably 50 mm or less. The width direction preferably corresponds to the axial direction with respect to the radius of curvature. The biasing means coupled to the arc-shaped contact surface acts as a safety device to prevent damage to the target pouch-type battery cell from collision with the probe.

[0011] In a preferred embodiment, the conductor has a convex side of the contact surface oriented toward the battery cell to be measured in a first direction. The arc-shaped contact surface can be configured to be movable in a sliding manner on the pouch-type battery case, in particular. Providing a convex arc-shaped contact surface supported by the biasing means allows the device to reliably engage with the battery cell, particularly the target position on the pouch-type battery cell, while minimizing the risk of damaging the cell. The convex arc-shaped contact surface, together with the biasing means, provides tolerance for aligning the probe with the battery cell to be measured, allowing the probe to contact the target cell even in the case of difficult contact parameters. For example, contact is possible even near the so-called "bat ear" when the battery case is elastically and / or irregularly deformed.

[0012] In a preferred embodiment that can be combined with the above-described embodiment, the conductor and the biasing member are integrally formed. Preferably, the biasing member and the conductor may contain or be composed of the same material. In a preferred embodiment, the probe, including the integrally formed conductor and biasing member, may be made of a conductive polymer. By providing the biasing member and conductor of the probe as one single integral body, mechanical and electrical interference along interfaces can be avoided. Furthermore, installation and replacement of the probe, which includes the conductor and biasing member as a single integral part, are even easier.

[0013] According to other preferred embodiments that may be combined with the embodiments described above, the conductor and / or the biasing member may include, and in particular may be embodied in, a sheet of metal. In particular, the conductor and / or the biasing means may include, or be embodied in, a sheet of stainless steel. The metal sheet may preferably have a thickness of less than 1 mm, preferably less than 0.5 mm, more preferably less than 0.3 mm, and particularly less than 0.15 mm. The metal sheet may have a thickness of 0.001 mm or more, particularly 0.01 mm or more, and preferably 0.05 mm or more. Stainless steel has been shown to provide high wear resistance while, on the one hand, providing suitable conductivity for measurement and elasticity that allows deformation of the probe so as not to engage with but damage the pouch-type battery cell of the target. In particular, in the case of probes that frequently come into contact with the sealed and / or cut edges of pouch-type battery cases, the sharp edges of the pouch can substantially cut the contact surface, causing severe wear on the probe.

[0014] In a preferred embodiment of the apparatus that may be combined with the embodiments described above, the biasing member includes a helical spring. The helical spring may be a mainspring in particular. The width direction of the arced contact surface preferably corresponds to the helical axial direction. The helical-shaped spring may include at least 0.5 windings, particularly at least 1.0 winding, preferably at least 1.25 windings, and more preferably at least 1.5 windings. Alternatively or in addition, the helical spring may include 10 windings or less, particularly 5 windings or less, and preferably 2 windings or less. Those skilled in the art will understand that one winding means a 360° helical rotation. Spiral windings of 250° to 750°, particularly 300° to 600°, preferably about 540° or about 450°, may lead to particularly advantageous properties. The main spring may refer to a band-shaped body, preferably of constant width and / or thickness, that rotates in a diameter that continuously decreases in the thickness direction around a central point. The inner and / or outer ends of the helical spring, in particular the main spring, may have radially projecting terminal sections. The spring may have an inner end with a terminal section that projects radially inward. The radially inward projecting inner end can stabilize the helical spring, in particular the main spring. As an addition or alternative, the helical spring, in particular the main spring, may have an outer end with a terminal section that projects radially outward. The terminal section end that projects radially inward or outward can be used to mount the helical spring to a holding member or the like. The inner and / or outer terminal sections may be aligned in particular in a first direction.

[0015] In other embodiments that can be combined with the embodiments described above, the probe includes two or more arc-shaped contact surfaces. In particular, the two or more arc-shaped contact surfaces may each comprise a biasing member. Preferably, each arc-shaped contact surface is associated with one individual biasing member. For example, the probe may comprise two arc-shaped contact surfaces, each connected to its own biasing member, and preferably, each arc-shaped contact surface is formed integrally with its respective biasing member. For example, a probe including multiple arc-shaped contact surfaces on two helical springs, particularly a main spring, can be used to increase the contact area between the probe and the battery cell being measured.

[0016] In an optional, preferred embodiment that may be combined with the embodiments described above, the apparatus may additionally include a holding member. The holding member is configured to secure a section of the biasing member, such as the outer end distal to the conductor. The section may be an end, such as the outer or inner end of the biasing member opposite the conductor, particularly in a first direction. By providing the end configured to be supported by the holding member to the end opposite the biasing member relative to the conductor, particularly its contact surface, the entire volume of the biasing member can be used to provide elasticity and deflection for elastically applying to the contact surface of the pouch-type battery cell in question.

[0017] In an example of the development of an additional device including a holding member, the holding member may be a clamp and / or may include a serrated holding surface. It may be preferable that the holding member has two opposing serrated holding surfaces of complementary shapes, in which case the projection of the first pad (jaw) of the holding member protrudes into the receptions of the second pad of the second holding member. The holding member using complementary serrated holding surfaces can provide a reliable positive engagement for securely fixing the probe.

[0018] In additional development examples that may be combined with the above, the holding member may be movable to connect with the biasing member in a second direction intersecting the first direction. In particular, the second direction may be perpendicular to the first direction. Preferably, the holding member is movable to connect with the biasing member in a spring-loaded manner or using at least one fastening bolt for fastening the biasing member. A spring-loaded holding member may be called a clip-type holding member. The holding member may be configured to grip two opposing sides of the biasing member, particularly using serrated holding surfaces (jaws).

[0019] In another development example of a device including a holding member, which can be combined with the above, the holding member may include or consist of a conductive material, particularly a metal such as brass. The use of a conductive holding member improves the performance of electrical measurements, including insulation voltage measurements.

[0020] The present invention also relates to a system for measuring at least one electrical parameter of a battery cell, in particular the insulation voltage, the system comprising at least one device, particularly two or more, for example, three or four devices, as described above. In a particularly preferred embodiment, the device comprises exactly two of the devices described above or exactly four of the devices described above. The system can be applied to a given group of pouch-type battery cells having uniform dimensions. The system can be applied such that two or more devices are positioned to engage with predetermined target locations on the battery cell to be measured, particularly sealed edges, for example, locations adjacent to the first or second electrode leads of the pouch-type battery cell and / or corner areas of the pouch-type battery cell.

[0021] The system for measuring at least one electrical parameter also includes current and / or voltage sensors. In particular, the conductor of the at least one probe is electrically coupled to the current and / or voltage sensor. The conductor may preferably be electrically coupled to the voltage sensor to determine a voltage, in particular an isolation voltage, in particular a voltage between the contact point of the probe and at least one reference point. The system may also additionally include at least one reference connection for contact with the first electrode lead, the second electrode lead, and / or electrical ground. The reference connection may be electrically coupled to the voltage sensor. The system may include one or more voltage sensors coupled to two or more devices. The two or more devices may preferably use the same voltage sensor or multiple voltage sensors. The system may comprise one single (shared) voltage sensor electrically coupled to the probes of two or more devices. The system may preferably be part of an assembly containing at least one, preferably exactly one, pouch-type battery cell of the subject.

[0022] According to another aspect of the present invention, a method is provided for measuring at least one electrical parameter, in particular insulation voltage, of a battery cell, in particular a pouch-type battery cell, using one or more of the devices described above. The method provides a battery cell to be measured, in particular a pouch-type battery cell including a sealed edge portion. In the method for measuring at least one electrical parameter, in particular insulation voltage, the conductor is engaged with the sealed edge portion in a first direction. The coupling of the conductor with the pouch-type battery cell in the first direction may cause deflection of the biasing means.

[0023] In a preferred embodiment of a method for measuring at least one electrical parameter of a battery cell, particularly an insulation voltage of a pouch-type battery cell, the electrical parameter of the pouch-type battery cell to be measured, particularly the insulation voltage, is determined while the conductor remains engaged with at least one sealed edge portion of the pouch-type battery cell.

[0024] In a preferred embodiment of a method for measuring at least one electrical parameter, particularly the insulation voltage, of a battery cell, especially a pouch-type battery cell, the at least one conductor is preferably moved in a direction intersecting the first direction translationally or in a pivoting manner. The moving direction of the conductor can particularly be perpendicular to the first direction. By moving the conductor along the sealed edge portion in a direction intersecting the first direction, preferably the second direction, the arcuate contact surface preferably slides along the sealed edge portion of the battery cell to be measured. By moving the conductor along the sealed edge portion, electrical parameters, particularly the insulation voltage, can be detected at a plurality of target positions and / or reference positions along the edge of the pouch-type battery case, and a particularly reliable measurement method can be realized. In such an additional development example, it may preferably be possible that the conductor comprises a metal sheet, particularly stainless steel, or is made of a metal sheet and is integrally formed with a biasing member, particularly a helical spring, particularly a biasing member formed as a main spring. The preferred embodiments of the method can be applied in combination or individually.

Advantages of the Invention

[0025] According to an embodiment, a particularly reliable elastic device, system and method for measuring at least one electrical parameter, particularly the insulation voltage, of a pouch-type secondary battery can be provided compared to the designs of the prior art, and damage to the battery case or the probe can be prevented. And the lifespan of the probe can be significantly extended by the embodiment. Therefore, the maintenance, installation and / or removal of the measuring device are facilitated.

[0026] The advantages of the present invention are not limited to the above-mentioned advantages, and other further advantages not mentioned above can be clearly understood by those skilled in the art from the description of the appended claims.

Brief Description of the Drawings

[0027] [Figure 1] It is a schematic cross-sectional view of an apparatus for forming a secondary battery. [Figure 2] It is a schematic diagram of a system including two devices for measuring at least one electrical parameter, particularly the insulation voltage, of a pouch-type battery cell. [Figure 3a] It is a schematic diagram of a holding member in a first state for fixing a probe. [Figure 3b] It is a schematic diagram of the holding member of FIG. 3a in a second state for releasing the fixing of the probe. [Figure 4] It is a schematic illustration of another probe. [Figure 5] It is a schematic illustration of a double probe. [Figure 6] It is a schematic illustration of a third probe.

Embodiments for Carrying Out the Invention

[0028] Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement them. The present invention can be modified in various different ways and is not limited to the embodiments described herein.

[0029] Parts not related to the description are omitted for clarity, and the same reference numerals throughout the description indicate the same elements.

[0030] Also, the sizes and thicknesses of the elements in the drawings are arbitrarily shown for convenience of explanation, and the present invention is not necessarily limited to what is shown in the drawings. The thicknesses of the layers and regions in the drawings are exaggerated for clarity. The thicknesses of some layers and regions in the drawings are exaggerated for convenience of explanation.

[0031] Furthermore, when an element such as a layer, film, region, or plate is described as being "on top of" or "above" another element, it can be understood that it may be directly above the other element, or that an intervening element may be present. In contrast, when an element is described as being "directly on top of" another element, it means that no other intervening element is present. Also, the words "on top of" or "above" mean being positioned above or below a reference part, and do not necessarily mean being positioned at the upper end of the reference part in the opposite direction of gravity. On the other hand, just as when an element is described as being located "on top of" or "above" another part, when an element is described as being located "below" or "below" another part, it can be understood by referring to the above.

[0032] Furthermore, whenever a part is referred to as "containing" or "having" a particular component throughout a description, this means that, unless otherwise explicitly stated, it may include other components as additions without excluding the other components.

[0033] Furthermore, when the term "plane" is used throughout the explanation, it refers to viewing the subject from above, and when the term "cross-section" is used, it refers to viewing the subject from the side of a vertically cut cross-section.

[0034] The following describes a pouch-type battery case and an apparatus and system for measuring the electrical characteristics, particularly the insulation voltage, of pouch-type battery cells, with reference to the attached drawings.

[0035] Figure 1 shows an exemplary pouch-type battery cell 110. For example, the pouch-type battery cell 110 has a structure in which two electrode leads 111 and 112 protrude from a first end 114a and a second end 114b opposite the first end 114a of the cell main body 113. Multiple battery cells 110 can be stacked to form a battery cell stack. In particular, the electrode leads 111 and 112 are connected to an electrode assembly (not shown) inside the pouch-type battery and protrude from the electrode assembly (not shown) to the outside of the battery cell 110. For example, the first electrode tab 111 protrudes from a first side surface of the electrode assembly and can be operably coupled to the negative electrode, and the second electrode tab 112 protrudes from a second side surface of the electrode assembly and can be operably coupled to the positive electrode. The electrode tabs 111 and 112 may each include an insulation part 117 configured to be positioned between the corresponding overlapping lateral portions 114a or 114b of the battery case 114. The pouch-type battery cell 110 includes an electrode assembly comprising a positive electrode, a negative electrode, and a separator membrane between the positive and negative electrodes, and an electrolyte solution. The electrode assembly and the electrolyte solution are enclosed by the cell case 114.

[0036] The cell case 114 can be formed from a laminated sheet (pouch film) comprising at least one resin layer and at least one metal layer. The cell case 114 acts as a mechanical, fluid, and electrical barrier to protect the internal electrode assembly and electrolyte solution from the surroundings. The cell case 114 forms a barrier between the internal electrode assembly and electrolyte solution and the external surroundings, while leaving the electrode leads 111 and 112 as the sole electrical pathways.

[0037] The above-mentioned pouch film may have a laminated structure comprising, for example, a metal film and one or more synthetic material layers. For example, the metal film may be made of aluminum (Al), iron (Fe), copper (Cu), chromium (Cr), manganese (Mn), nickel (Ni), magnesium (Mg), zinc (Zn), or a combination or alloy thereof. For example, one or each of the synthetic material layers may be made of polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, acrylic polymer, polyacrylonitrile, polyimide, polyamide, cellulose, aramid, nylon, polyester, poly(p-phenylene), benzobisoxazole, polyarylate, Teflon, glass fiber, or a combination thereof, or may contain them. The above-mentioned pouch film has a film thickness. The film thickness is preferably constant and / or continuous in the transverse film direction. The film thickness is preferably constant and / or continuous in the longitudinal film direction. The pouch film has a first surface configured to act as the internal surface of the pouch-type battery case, and a second surface configured to act as the external surface of the pouch-type battery case. The first surface can come into contact with the electrode assembly located inside the pouch-type battery case. The second surface is the side that does not face the electrode assembly and may optionally come into contact with the environment surrounding the secondary battery.

[0038] The pouch film may have a thickness of 100 μm to 250 μm, particularly 160 μm to 200 μm, preferably 175 μm to 190 μm. Preferably, the pouch film includes a gas barrier layer made of metal. The metal of the gas barrier layer of the pouch film is preferably aluminum and / or an aluminum-containing alloy, particularly an AA80XX series aluminum alloy. The alloy number of the aluminum alloy may be AA8021. The aluminum alloy may contain about 1.3% to about 1.7% by weight of iron and about 0.2% or less by weight of silicon, and may have a grain size of about 10 μm to about 13 μm. The thickness of the gas barrier layer may be 30 μm to 150 μm, particularly 70 μm to 120 μm, preferably 80 μm to 100 μm. The pouch film may also include a sealant layer made of a first polymer, preferably formed as the innermost layer. The thickness of the sealant layer may be 60 μm to 100 μm. Additionally or alternatively, the pouch film may include a surface protection layer made of a second polymer, preferably formed as the outermost layer. The first polymer may be the same as or different from the second polymer. In particular, the gas barrier layer is laminated between the surface protection layer and the sealant layer. The pouch film may also include a drawing assistance layer made of a third polymer. The third polymer may be the same as or different from the first polymer and / or the second polymer. The drawing assistance layer may be laminated between the surface protection layer and the gas barrier layer. The thickness of the above-mentioned drawing auxiliary layer can be 10 μm to 75 μm, and particularly 20 μm to 50 μm.

[0039] The first polymer described above can be made from one or more materials selected from the group consisting of polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, acrylic polymers, polyacrylonitrile, polyimide, polyamide, cellulose, aramid, nylon, polyester, poly(p-phenylenebenzobisoxazole), polyarylate, Teflon, and glass fiber. In particular, polyolefin resins such as polypropylene (PP) or polyethylene (PE) may be the main component of the first polymer. Polypropylene (PP) can be selected as the main component of the sealant layer because it provides excellent mechanical properties including tensile strength, rigidity, surface hardness, abrasion resistance, and heat resistance, as well as excellent chemical properties including corrosion resistance.

[0040] The above-mentioned second polymer can be made from one or more of the following: polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, acrylic polymers, polyacrylonitrile, polyimide, polyamide, cellulose, aramid, nylon, polyester, poly(p-phenylenebenzobisoxazole), polyarylate, Teflon, and glass fiber. It may be advantageous to primarily use polymers with desirable wear resistance and heat resistance, such as polyethylene terephthalate (PET).

[0041] The above-mentioned third polymer can be made from one or more of the following: polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, acrylic polymers, polyacrylonitrile, polyimide, polyamide, cellulose, aramid, nylon, polyester, poly(p-phenylenebenzobisoxazole), polyarylate, Teflon, and glass fiber. In particular, nylon resin can be readily bonded to polyethylene terephthalate (PET) in the surface protective layer and can exhibit similar behavior to the aluminum alloy in the moisture barrier layer during and after the drawing process. Therefore, nylon resin can be used as the main component of the third polymer.

[0042] In this example, the battery cell under test is shown exemplary as a pouch-type battery cell 110. Those skilled in the art will understand that while the battery cell under test may be embodied in a pouch-type battery cell 110 in some preferred embodiments, the apparatus, system, or method described herein may be applied to other types of battery cells as an alternative. The illustrated pouch-type battery cell 110 may be manufactured, for example, by folding two portions of foil to form a cell case 114, enclosing and encapsulating an internal electrode assembly. The cell case 114 may be folded around a folding portion 115 that divides the cell case 114 into two parts. In this way, the left lateral portions 114a of each of the two portions fold over each other, and the right lateral portions 114b also fold over each other. In addition, a pair of intermediate portions 114c of each portion, i.e., distal intermediate portions 114c from the folding portion 115, fold over each other. To seal and close the pouch-type battery cell 110, the paired overlapping portions 114a, 114b, and 114c are sealed and attached to each other. This forms sealed edge portions 114sa, 114sb, and 114sc. Such sealed portions 114sa, 114sb, and 114sc may have a structure formed by methods such as heat fusion or friction welding. The overlapping upper and lower intermediate portions 114c, i.e., the sealed intermediate portions 114c, which are attached to each other, can be folded one or more times toward the folding portion as a flap 114f. Optionally, the attachment method can also be applied to the folding portion 115. However, it may be preferable that the folding portion 115 provides a sealing function without additional attachment or sealant, particularly due to the material properties of the foil forming the cell case 114 including the folding portion 115.

[0043] The folding portion 115 can extend along one edge of the battery cell 110. In some embodiments, a projection 110p (so-called "bat-ear") of the battery cell 110 can be formed on the edges of the left or right lateral portions 114a, 114b adjacent to the folding portion 115, respectively. Additionally or alternatively, a terrace portion 116 can be formed between the electrode leads 111 and 112 and the cell body 113 while the cell case 114 is sealed with the protruding electrode leads 111 and 112 interposed between them. That is, the battery cell 110 may include a terrace portion 116 formed to extend from the cell case 114 in the direction in which the electrode leads 111 and / or 112 protrude.

[0044] The cell case must be mechanically robust and form a sealingly tight encapsulation around the internal battery components. The battery cell 110 is defective if the electrolyte solution leaks through the cell case 114, or if one or both of the electrode leads 111, 112, or the internal electrode assembly, is electrically connected to the cell case 114. Defective batteries must be identified and sorted to prevent their use in battery stacks, which could lead to performance degradation or even hazardous use.

[0045] Figure 2 shows the pouch-type battery cell 110 as described above, together with a system 10 including two devices 1 for measuring at least one electrical parameter of the pouch-type battery cell, in particular the insulation voltage. The system may preferably include one voltage sensor (not shown) electrically coupled to the two devices 1. The devices 1 are coupled to the system 10 so as to be movable in a forward direction F to contact the (left) lateral edge 114a of the pouch-type battery case 114. These devices 1 are laterally spaced to contact the first electrode lead 111 of the pouch-type battery 110 and the sealed edge portion 114sa adjacent to the insulating portion 117 surrounding the lead 111, which is interposed between the lead 111 and the pouch foil forming the battery case 114.

[0046] Each device 1 has a holding member 9 to which each probe 3, which is integrally formed by a conductor 5 and a biasing means 7, is securely attached. Fastening bolts 95 are fastened to the holding member 9 such that the opposite end of the probe is firmly pressed against the holding plate 96 and the holding plate 96 is pressed against the side of the holding member 9.

[0047] Each probe 3 has a conductor 5 having an arc-shaped contact surface 51. The conductor 5 forms a 180° curve with an arc-shaped contact surface 51 on its outer circumference. The width of each contact surface 51 extends not only in the field of view direction but also along the central axis around which the radially arc-shaped contact surface 51 bends. The width of the conductor 5 has a diameter corresponding to approximately twice the radius of curvature of the arc-shaped contact surface 51. The probe 3 can preferably be made of a conductive material such as conductive rubber or a metal sheet. The probes 3 of the multiple devices 1 of the system 10 can have the same dimensions. For example, the probe 3 may be loop-shaped and may have opposing ends that are positioned on top of each other relative to the holding member 9 on the opposite side of the arc-shaped contact surface 51 in the first direction F.

[0048] The holding member 9 is hinged to the support bracket 11 of the system 10. The holding member 9 can be firmly coupled to the support bracket 11 to set a predetermined lateral distance between adjacent devices 1, for example, according to a predetermined measuring distance corresponding to a given pouch-type battery cell 110. The system 10 may include a linear actuator 13 for moving the device 1 forward and backward in a first direction F for engagement with and disengagement of the target pouch-type battery cell 110. The device 1 can be advanced in the first direction F to be contact-connected in particular to create a mechanical and electrical connection with the pouch-type battery cell 110 at the convex arc-shaped surface 51 of the conductor 5. When the probe 3 contacts the pouch-type battery cell 110, the biasing means 7 resiliently urges the conductor 5 against the pouch-type battery cell 110 to create a reliable electrical connection. The elasticity of the biasing means 7 also allows the probe 3 to deform in response to its engagement with the pouch-type battery cell 110, thereby preventing damage to the cell or the probe.

[0049] The system 10 described above can also be configured to move one or more devices 1 in a second direction S. One or more devices can be moved in slidable contact with, in particular, a pouch-type battery cell. For example, the probe 3 can be moved in such a way that its convex arc-shaped contact surface 51 slides along sealed edge portions 114sa, 114sb, or 114sc.

[0050] Figures 3a and 3b and Figures 4-6 show various embodiments of the probe 3 for contacting the target pouch-type battery cell 110.

[0051] Figure 3a shows the holding member 9 in a closed state that secures the probe 3; Figure 3b shows the holding member 9 in an open state that releases the probe 3. The width of the conductor 5 has a diameter that corresponds to approximately twice the radius of curvature of the arc-shaped contact surface 51.

[0052] Figures 3a and 3b show a clip-shaped holding member 9 having opposing jaws 92 and 94. The first jaw 92 can be configured to attach to a support bracket of the system 10. The second jaw 94 can be rotatably connected to the first jaw 92 by a spring-loaded mechanism that presses the second jaw 94 against the first jaw 92, so that the serrated contact surfaces 93 of the jaws are securely coupled. The end section 79 of the biasing means 7 of the probe 3 can be fixed by the secure coupling of the jaws 92 and 94 when the holding member 9 is closed. This securely fixes the probe 3 against displacement in the second direction S and electrically securely connects it to the holding member, which can be made of a conductive material, such as brass. When the holding member 9 is open, the second jaw 94 is detached from the first jaw 92, allowing the probe 3 to be easily removed and replaced.

[0053] The probe 3 in Figures 3a and 3b has a helical shape including a 540° winding. The internal end portion 59 and end section 79 of the probe body are oriented parallel to a first direction F to reinforce the probe in the axial direction. The outer radius of the diameter of the conductor 5 and the biasing member 7 may be approximately 25 mm. The internal end portion 59 is approximately half the radius of the conductor 5. The external projection forming the distal end section 79 from the arc-shaped contact surface 51 is longer than the width and / or diameter of the conductor 5. The convexly bent contact surface 51 is formed on its outer circumference. The contact surface 51 is oriented in a first direction F to engage with a pouch-type battery (not shown) of interest.

[0054] Figure 4 is a schematic diagram of another probe 3 that engages with a schematicly shown pouch-type battery cell 110. The schematicly shown probe 3 has a circular shape including a conductor 5 having an arc-shaped contact surface 51 that engages with the measurement position of the edge of the pouch-type battery cell, and a biasing means 7. The width of the conductor 5 has a diameter corresponding to approximately twice the radius of curvature of the arc-shaped contact surface 51. The contact surface 51 is oriented in a first direction F so as to engage with the pouch-type battery 110 in question.

[0055] Figure 5 shows a probe 3 similar to the loop-shaped probe described above in relation to the system of Figure 1. In the embodiment of Figure 5, the convex arc-shaped contact surface 51 has a particularly large radius of curvature, which is greater than the width of the conductor 5. The large radius of curvature allows the contact surface 51 to be flattened, preferably to line contact, in order to increase the contact area with the pouch-type battery cell 110. The arc-shaped contact surface 51 is connected to two terminals, both of which project radially inward. The arc-shaped contact surface 51 is oriented in a first direction F to engage with the pouch-type battery in question. The arc section extends to less than 180°, particularly less than 90°, preferably less than 60°, and more preferably less than 45°. The terminal sections 78 form acute angles with respect to each other. The terminal sections 78 are preferably arranged mirror-symmetrically with respect to the first direction F.

[0056] Figure 6 is a schematic diagram of a double probe 3, which includes two pairs of integrally formed conductors 5 and biasing members 7, each embodied by a main spring 71. The holding section 79 distal to the arc-shaped contact surface 51 protrudes tangentially from the circular or helical body. The contact surface 51 is oriented in a first direction F to engage with the target pouch-type battery 110. The conductors 5 and biasing members 7 are preferably arranged mirror-symmetrically with respect to the first direction F. The holding sections 79 can be placed flat against each other and can be securely fixed by the same holding member (not shown). The circular or helical combination of the biasing members 7 and conductors 5 can extend from the front end of the holding section. By providing a double probe with two arc-shaped contact surfaces 51, the contact area between the probe 3 and the target battery cell 110 can be significantly increased. Each adjacent conductor 5 has a diameter approximately twice the radius of curvature of the arc-shaped contact surface 51. [Explanation of symbols]

[0057] 1: Equipment 3: Probe 5: Conductor 7: Biasing component 9: Holding component 10: System 51: Contact surface 59: Internal terminal 71: Mainspring 79: Section (distal to the conductor) 91: Clamp 92, 94: Joe 93: Serrated holding surface 95: Fixing bolts 96: Holding Plate 110: Battery cell 110p: Protruding part ("Bat ear") 111: First electrode lead 112: Second electrode lead 113: Cell body 114: Cell case 114a:(Left side) Lateral part 114b: (Right side) Lateral part 114c: Middle part 114sa: Sealed portion 114sb: Sealed portion 114sc: Sealed portion 114f: Flap 115: Folding section 116: Terrace 117: Insulation F: 1st direction S:Second direction

Claims

1. An apparatus for measuring at least one electrical parameter of a battery cell, in particular the insulation voltage, Includes at least one probe, The aforementioned probe A conductor having an arc-shaped contact surface configured to be electrically coupled to a current and / or voltage sensor and to engage with the battery cell to be measured, An apparatus comprising a biasing member configured to elastically mount the conductor in a first direction.

2. The apparatus according to claim 1, wherein the convex side surface of the contact surface is oriented so as to face the battery cell to be measured in the first direction.

3. The apparatus according to claim 1 or 2, wherein the conductor and the biasing member are integrally formed.

4. The apparatus according to any one of claims 1 to 3, wherein the conductor and / or the biasing member comprises a metal sheet, particularly stainless steel.

5. The apparatus according to any one of claims 1 to 4, wherein the biasing member includes a helical spring.

6. The apparatus according to any one of claims 1 to 5, wherein the contact surface is arranged on the side surface of the biasing member.

7. The apparatus according to any one of claims 1 to 6, wherein the probe includes two or more arc-shaped contact surfaces.

8. The apparatus according to any one of claims 1 to 7, further comprising a holding member configured to fix a section of the biasing member distal to the conductor.

9. The apparatus according to claim 8, wherein the holding member includes a clamp and / or a serrated holding surface.

10. The apparatus according to claim 8 or 9, wherein the holding member is movable so as to engage with the biasing member in a second direction intersecting the first direction, particularly in a second direction perpendicular to the first direction.

11. The apparatus according to any one of claims 8 to 10, wherein the holding member includes a conductive material, particularly a metal such as brass.

12. A system for measuring at least one electrical parameter of a battery cell, in particular the insulation voltage, At least one apparatus according to any one of claims 1 to 11, Current and / or voltage sensors, A system that includes this.

13. A method for measuring at least one electrical parameter of a battery cell, particularly its insulation voltage, using the apparatus described in any one of claims 1 to 11, A battery cell to be measured, including the sealed edge portion, is provided; A method in which the conductor is engaged with the sealed edge portion in the first direction.

14. The method according to claim 11, wherein the electrical parameters of the battery cell under measurement, particularly the insulation voltage, are determined while the conductor remains engaged with at least one of the sealed edge portions.

15. The method according to claim 13 or 14, wherein the conductor is moved along the sealed edge portion in a direction intersecting the first direction, particularly in a direction perpendicular to the first direction, and the arc-shaped contact surface moves along the sealed edge portion of the battery cell to be measured.

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