Method for inspecting short circuit of battery

Abstract

The present invention relates to a method for inspecting a short circuit of a battery and a method for processing a battery. The method for inspecting a short circuit of a battery comprises the steps of: preparing a battery in which a plurality of cells are aligned; applying a current to the battery in which the plurality of cells are aligned; measuring a change amount of a magnetic field around the plurality of cells in a direction in which the plurality of cells are aligned in the battery in which the plurality of cells are aligned; and determining a normal unit including a normal cell and a short circuit unit including a short circuited cell from among the plurality of cells, through the change amount of the magnetic field.

Description

Battery short circuit test method

[0001] The present invention relates to waste battery recycling and to a method for recovering valuable metals from waste batteries.

[0002] This application claims priority to Korean Patent Application No. 10-2024-0191922, filed on December 19, 2024, the entire contents of which are incorporated herein by reference.

[0003]

[0004] Battery demand is rapidly increasing as they are widely used not only in electronic devices such as smartphones and mobile devices but also in electric vehicles. The demand for these batteries is expected to rise further as the demand for electric vehicles increases as the next-generation mode of transportation.

[0005] Since the aforementioned electric vehicle requires a battery with a large electrical capacity, it is installed and used in the vehicle in units of multiple battery cells, modules composed of multiple battery cells, and packs composed of multiple modules. As the usage of the electric vehicle increases rapidly, the amount of waste generated from batteries used in the electric vehicle is also increasing.

[0006] The above battery may be used by mixing copper (Cu) and aluminum (Al) used as a current collector, lithium (Li), nickel (Ni), cobalt (Co), and manganese (Mn) containing oxides constituting the cathode, graphite constituting the anode, a separator separating the cathode and the anode, an electrolyte injected into the separator, and a carbonate organic material such as propylene carbonate, and the salt may be, for example, LiPF6 (Lithium hexafluorophosphate).

[0007] Recently, the issue of disposing of lithium-ion batteries, such as spent electric vehicle batteries, has emerged globally. These lithium-ion batteries pose fire hazards due to organic solvents and contain explosive substances as well as heavy metals such as Ni, Co, Mn, and Fe. Consequently, there are technical issues regarding the safe dismantling of these spent batteries.

[0008] The above waste batteries may be generated from process scrap produced during battery manufacturing, electric vehicles after overuse, or energy storage devices. The above waste batteries exist in cell units, module units, or pack units, and it is common practice to inspect the voltage at the pack or module level. In the case of the above waste batteries, many are generated when they reach the end of their lifespan, but in some cases, they are generated when the electrodes are short-circuited.

[0009] It is important to distinguish the aforementioned waste batteries when they are caused by short-circuited electrodes, as electrical discharge is impossible. However, since a single battery pack consists of hundreds of cells connected in series or parallel, there is a problem in that it is difficult to perform electrical discharge because it is not easy to locate short-circuited cells in the parallel structure.

[0010] To solve the above problem, a water discharge method is used in which the waste battery is separated into cell units, the outer casing is cut, and then the battery is discharged by immersing it in water or brine. However, the above water discharge method has the problem that the sodium and chlorine in the wastewater or brine can cause various problems in subsequent processes.

[0011] The technical problem that the present invention aims to solve is to provide a short-circuit inspection method for batteries to easily locate short-circuited cells in a pack or module in which multiple batteries are combined and to safely apply them to the recycling process of waste batteries.

[0012] Another technical problem that the present invention aims to solve is to provide a method for processing a battery that safely discharges the battery even if a short-circuited cell is included within the battery, and reduces the risk of fire when the discharged battery is crushed.

[0013] A short-circuit inspection method for a battery according to one embodiment of the present invention comprises the steps of: preparing a battery in which a plurality of cells are aligned; applying a current to the battery in which a plurality of cells are aligned; measuring a change in the surrounding magnetic field of the plurality of cells in the direction in which the plurality of cells are aligned in the battery in which a plurality of cells are aligned; and determining a normal section including a normal cell among the plurality of cells and a short-circuit section including a short-circuited cell through the change in the magnetic field, wherein the normal section and the short-circuit section can be determined by the difference in signal change derived from the change in the magnetic field. In one embodiment, the battery in which a plurality of cells are aligned may be a waste battery.

[0014] In one embodiment, the short-circuit inspection method of the battery may be performed before crushing the waste battery for recycling. In one embodiment, the step of applying current to the battery in which a plurality of cells are aligned may perform charging and discharging to the battery in a range of 3.0 to 4.2 V (voltage setting in the case of NCM).

[0015] In one embodiment, the step of measuring the change in the surrounding magnetic field of the plurality of cells in the direction in which the plurality of cells are aligned in the battery in which the plurality of cells are aligned may involve using a magnetic sensor to measure at least one of the electric field and the magnetic field surrounding the battery in which the plurality of cells are aligned. In one embodiment, the signal change may determine at least one non-uniform section as the short section from the one-dimensional or two-dimensional result values ​​derived from the normal section and the short section.

[0016] In one embodiment, the short-circuit portion may have a voltage value in the range of 2.5V to 3.7V lower than the normal portion in terms of the amount of change in the magnetic field. In one embodiment, the amount of change in the magnetic field may be acquired as a two-dimensional image.

[0017] In one embodiment, the magnetic sensor can scan the magnetic sensor in any one of the horizontal, vertical, and height directions and measure the amount of change in the magnetic field. In one embodiment, the area satisfying the following Equation 1 in the amount of change in the magnetic field can be determined as the short circuit portion.

[0018] <Equation 1>

[0019] A - B ≥ 2.0 V

[0020] (In Equation 1 above, A represents the target voltage value set during the step of applying current to a battery in which multiple cells are aligned, B represents the voltage value of a specific cell in the change of the surrounding magnetic field of the multiple cells, and 2.0V represents the threshold value of the difference.)

[0021] A battery processing method according to another embodiment of the present invention relates to a battery processing method for recycling a waste battery in which a plurality of cells are aligned, comprising a battery short-circuit inspection step for determining a short-circuited cell among the plurality of cells, a step of determining a battery module selected from the battery short-circuit inspection as an abnormal battery module, and a step of stabilizing and crushing the abnormal battery module. The battery short-circuit inspection step comprises a step of preparing a battery in which a plurality of cells are aligned, a step of applying current to the battery in which a plurality of cells are aligned, a step of measuring a change in the surrounding magnetic field of the plurality of cells in the direction in which the plurality of cells are aligned in the battery in which a plurality of cells are aligned, and a step of determining a normal part including a normal cell among the plurality of cells and a short-circuit part including a short-circuited cell through the change in the magnetic field.

[0022] In one embodiment, the short-circuit portion may have a voltage value 2.5 to 3.7 V lower than the normal portion in terms of the amount of change of the magnetic field.

[0023] In one embodiment, the region satisfying the following Equation 1 in the amount of change of the magnetic field can be determined as the short-circuit portion.

[0024] <Equation 1>

[0025] A - B ≥ 2.0 V

[0026] (In the above Equation 1, A represents the target voltage value set during the step of applying current to a battery in which multiple cells are aligned, and B represents the voltage value of a specific cell in the change of the surrounding magnetic field of the multiple cells.)

[0027] In one embodiment, the step of measuring the change in the surrounding magnetic field of the plurality of cells may involve moving a magnetic sensor along either a first direction in which the plurality of cells are arranged or a second direction which is perpendicular to the first direction on a horizontal plane, and measuring the change in the magnetic field.

[0028] A battery short-circuit inspection method according to one embodiment of the present invention includes a step of determining a normal part and a short-circuit part as signal changes based on a value derived from a change in magnetic field amount, thereby easily selecting short-circuited cells from short-circuited cells in a pack or module in which multiple batteries are combined, and ensuring stability and economic efficiency when crushing batteries.

[0029] A battery processing method according to another embodiment of the present invention includes a short-circuit inspection method for a battery having the aforementioned advantages, thereby allowing the battery to be safely crushed rather than electrically discharged even if a short-circuited cell is contained within the battery, thus reducing the risk of fire.

[0030] FIG. 1 is a flowchart of a short-circuit inspection method for a battery according to one embodiment of the present invention.

[0031] FIG. 2 is a flowchart relating to a method for processing a battery according to one embodiment of the present invention.

[0032] FIG. 3 is a graph of signal results measured from a battery including a short-circuited cell according to one embodiment of the present invention.

[0033] FIGS. 4a to 4c are photographs and graphs showing two-dimensional scan image results of a battery including a short-circuited cell according to one embodiment of the present invention.

[0034] Terms such as first, second, and third are used to describe various parts, components, regions, layers, and / or sections, but are not limited thereto. These terms are used solely to distinguish one part, component, region, layer, or section from another part, component, region, layer, or section. Accordingly, the first part, component, region, layer, or section described below may be referred to as the second part, component, region, layer, or section without departing from the scope of the present invention.

[0035] The technical terms used herein are for the reference of specific embodiments only and are not intended to limit the invention. The singular forms used herein include plural forms unless phrases clearly indicate otherwise. As used in the specification, the meaning of "comprising" specifies certain characteristics, areas, integers, steps, actions, elements, and / or components, and does not exclude the presence or addition of other characteristics, areas, integers, steps, actions, elements, and / or components.

[0036] When it is stated that one part is "above" or "on" another part, it may be directly above or on the other part, or other parts may be involved in between. In contrast, when it is stated that one part is "directly above" another part, no other parts are interposed in between.

[0037] Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as generally understood by those skilled in the art to which this invention pertains. Terms defined in commonly used dictionaries are further interpreted to have meanings consistent with relevant technical literature and the present disclosure, and are not interpreted in an ideal or highly formal sense unless otherwise defined.

[0038] FIG. 1 is a flowchart of a short-circuit inspection method (S100) of a battery according to one embodiment of the present invention.

[0039] Referring to FIG. 1, a short-circuit inspection method (S100) of a battery according to one embodiment of the present invention may include the steps of: preparing a battery in which a plurality of cells are aligned (S110); applying current to the battery in which a plurality of cells are aligned (S120); measuring the change in the surrounding magnetic field of the plurality of cells in the direction in which the plurality of cells are aligned in the battery in which a plurality of cells are aligned (S130); and determining a normal section containing normal cells and a short-circuit section containing short-circuited cells among the plurality of cells through the change in the magnetic field (S140). Specifically, the short-circuit inspection method of a battery may be performed before the crushing process in a battery recycling process, and may involve selecting short-circuited cells while performing electric discharge. An abnormal battery module containing short-circuited cells may be separately fed into a process capable of crushing without removing residual energy, rather than general electric discharge. Therefore, when recycling a battery containing short-circuited cells, the battery recycling process can be performed more safely.

[0040] The step of preparing a battery in which a plurality of cells are aligned (S110) may prepare a battery comprising a module including a plurality of cells or a pack including a plurality of modules. The short-circuit inspection method of the present invention may be a step of identifying a short-circuited cell among the plurality of cells included in the module or the pack.

[0041] In one embodiment, the battery may be a waste battery. Specifically, the waste battery may include a battery that is difficult to use, such as a battery that has reached the end of its life or a short-circuited cell.

[0042] In one embodiment, the battery may have a plurality of cells aligned. Specifically, the plurality of cells may be aligned in one direction based on at least one of width, length, and height.

[0043] The step (S120) of applying current to the battery in which the plurality of cells are aligned may be a step of charging and discharging the battery in which the plurality of cells are aligned. Specifically, the step of applying current to the battery may be a step of supplying current to the battery to electrically discharge the battery.

[0044] In one embodiment, the step (S120) of applying current to the battery in which the plurality of cells are aligned may perform charging and discharging to the battery in a range of 3.0 to 4.2 V. Specifically, the battery may be charged and discharged in a range of 3.2 to 4.2 V, more specifically in a range of 3.4 to 3.8 V. For example, it may be performed while applying a normal discharge current. As the battery is charged and discharged at a voltage within the aforementioned range, electrical energy inside the battery is removed, thereby minimizing the possibility of fire caused by the battery's own energy in a subsequent process.

[0045] The step (S130) of measuring the change in the surrounding magnetic field of the plurality of cells in the direction in which the plurality of cells are aligned in the battery of the plurality of cells can measure at least one of the electric field and the magnetic field surrounding the battery of the plurality of cells aligned using a magnetic sensor. Specifically, the magnetic sensor can be placed adjacent to the battery of the plurality of cells aligned, and the magnetic sensor can be scanned in any one of the directions in which the plurality of cells are aligned, for example, horizontal, vertical, and height directions. More specifically, the step of measuring the change in the surrounding magnetic field of the plurality of cells can measure the change in the magnetic field by moving the magnetic sensor along a first direction in which the plurality of cells are arranged, a second direction which is perpendicular to the first direction and the horizontal plane, and a third direction which is perpendicular to the first direction and the second direction.

[0046] Specifically, the magnetic sensor may include various types of sensors, such as Hall sensors, MR sensors, and eddy current sensors, as non-limiting examples. More specifically, the magnetic sensor may be a Hall sensor. In one embodiment, the magnetic sensor may be included, for example, in a magnetizer device. Specifically, the magnetizer may be a magnetizer device comprising an electromagnet magnetizer, a coil, and a magnetic sensor.

[0047] Specifically, the magnetizing device may include an electromagnet magnetizer that induces magnetization, a coil positioned to surround a portion of the electromagnet magnetizer, and a magnetic sensor positioned around an object to be measured for the magnetic field to measure the magnetic field. More specifically, the magnetizing device may be positioned adjacent to the battery and may detect the magnetic field generated according to the charge / discharge voltage of the battery. The magnetizing device including the magnetic sensor may move in the direction in which the cells within the battery are aligned, detect the magnetic field of the cells, and detect the amount of change in the magnetic field of the battery.

[0048] In one embodiment, the change in magnetic field may be acquired as a one-dimensional image or a two-dimensional image. Specifically, the one-dimensional image may be, for example, an image of a one-dimensional signal that measures a magnetic field leaking in the vertical direction by a single Hall sensor. The one-dimensional image may be, for example, data obtained by enlarging two-dimensional image data, or data that confirms the magnetic field value in a specific cell.

[0049] Specifically, the two-dimensional image may be two-dimensional image data of a plurality of cells within the battery when the battery is scanned by a magnetizer device. Specifically, the two-dimensional image may be a verification of the magnetic field value of an area scanned by the magnetizer device for the entire battery containing a plurality of cells.

[0050] Specifically, a magnetizer device is positioned at the top of a battery module composed of multiple cells to measure the magnitude of the magnetic field at each cell location within the module where some of the cells are defective. More specifically, the analog voltage value of the magnetic field measured by each sensor is measured while switching, passes through a preamplifier to amplify the magnitude of minute signals, and converts the analog signal into digital through an AD converter.

[0051] Furthermore, the location of the short-circuit cell can be determined through microprocessing that compares signals between channels and identifies the short-circuit cell location. When the magnetic field values ​​at each location of the sensor are converted into voltage and displayed, it can be determined that a voltage drop occurs at the location where the short-circuit cell exists due to weak magnetic field strength, as shown in the graph of Figure 3.

[0052] The step (S140) of determining a normal portion including a normal cell among the plurality of cells and a short-circuit portion including a short-circuited cell through the amount of change in the magnetic field may be determined by the difference in signal change between the normal portion and the short-circuit portion. Specifically, the normal portion and the short-circuit portion can be identified through the amount of change in the magnetic field confirmed from the one-dimensional image or the two-dimensional image.

[0053] In one embodiment, the magnetic field sensor may be a magnetic sensor in which a plurality of channels of magnetic field sensors are arranged. Multiple channels of magnetic field sensors are configured in an array form to measure the distribution of the magnetic field generated by each cell.

[0054] The short-circuit portion may refer to at least one non-uniform section among the magnetic field change amounts. Specifically, among the image values ​​identified from the magnetic field change amount data values, the section where the voltage drops due to the short-circuit cell or the section where the magnetic field rapidly decreases or increases may be determined as the short-circuit portion. The normal portion is a section excluding the short-circuit portion, and may refer to an area having a uniform voltage or magnetic field excluding the non-uniform section among the magnetic field change amounts.

[0055] In one embodiment, the short-circuit portion may refer to a region where the voltage value is 2.0 V or lower than that of the normal portion in terms of the change in the magnetic field. Specifically, the short-circuit portion and the normal portion may be determined by the difference in voltage in terms of the change in the magnetic field. Specifically, the battery may maintain a predetermined voltage through a charging and discharging process. At this time, the normal portion may maintain a higher voltage than the short-circuit portion due to the charging and discharging process of the battery, and the short-circuit portion may maintain a lower voltage than the normal portion because current is not easily applied due to the charging and discharging process even after the charging and discharging process of the battery.

[0056] In one embodiment, the region satisfying the following Equation 1 in the amount of change of the magnetic field can be determined as a short-circuit section.

[0057] <Equation 1>

[0058] A - B ≥ 2.0 V

[0059] (In the above Equation 1, A represents the target voltage value set during the step of applying current to a battery in which multiple cells are aligned, and B represents the voltage value of a specific cell in the change of the surrounding magnetic field of the multiple cells.)

[0060] For example, in a cell with a charge state (SOC) in the range of 0 to 100% (3.0 to 4.2 V), the voltage of parallel-connected cells can be controlled very uniformly during normal operation. This can be determined as the normal voltage. If the battery includes a short-circuited cell, the internal resistance of the short-circuited cell decreases rapidly and consumes most of the voltage, and consequently, the short-circuit voltage, which is the voltage of the short-circuited cell, drops sharply to 0 to 0.5 V. Based on this, the short-circuit state can be determined by setting a threshold value for the difference between the normal voltage and the short-circuit voltage to a range of 2.5 to 3.7 V.

[0061] Equation 1 above may be a factor for identifying the location of a short-circuited cell within a battery. Specifically, regarding the change in the magnetic field, if there is a region satisfying Equation 1 above, it can be confirmed that the region signifies a short-circuited section containing a short-circuited cell. Equation 1 above may satisfy 2.0 V or higher, specifically 2.5 V to 3.7 V. A region satisfying Equation 1 above indicates the presence of a short-circuited cell within the battery, specifically the location of the short-circuited cell.

[0062] By satisfying the aforementioned range of Equation 1, a short-circuited cell within the battery can be identified. If Equation 1 does not satisfy the aforementioned range, it can be confirmed that there is no short-circuited portion containing a short-circuited cell within the battery.

[0063] FIG. 2 is a flowchart relating to a method for processing a battery according to one embodiment of the present invention.

[0064] Referring to FIG. 2, a battery processing method according to one embodiment of the present invention may include a battery short-circuit inspection step (S100) for determining a short-circuited cell among a plurality of cells, a step (S200) for determining a battery module selected from the battery short-circuit inspection as an abnormal battery module, and a stabilization crushing step (S300) for stabilizing crushing the abnormal battery module. Specifically, the battery processing method recycles a plurality of aligned batteries, and by identifying a short-circuited cell within the battery through electrical discharge of the battery and removing it separately, the battery crushing process can be performed more stably.

[0065] A short-circuit inspection step (S100) of a battery for determining a short-circuited cell among a plurality of cells may be a step of identifying a short-circuited cell that increases the possibility of fire occurrence before performing a battery crushing process. Specifically, the short-circuit inspection step (S100) of the battery may include a step of preparing a battery in which a plurality of cells are aligned (S110), a step of applying current to the battery in which a plurality of cells are aligned (S120), a step of measuring the change in the surrounding magnetic field of the plurality of cells in the direction in which the plurality of cells are aligned in the battery in which a plurality of cells are aligned (S130), and a step of determining a normal part containing a normal cell among the plurality of cells and a short-circuit part containing a short-circuited cell through the change in the magnetic field (S400). A detailed description thereof may be referenced to the contents of FIG. 1 to the extent that it does not contradict.

[0066] The step (S200) of determining that the battery containing the short-circuited cell, determined from the short-circuit inspection of the battery, is an abnormal module that is not electrically discharged, can determine that the module containing the battery is an abnormal module and separate it separately if it contains a short-circuited cell. The determination of the abnormal module can be confirmed through the step of determining the short-circuit part described in FIG. 1.

[0067] The stabilization crushing step (S300) for stabilizing and crushing the above-mentioned abnormal battery module is a crushing step capable of crushing the module including the short-circuited cell without removing residual energy other than electrical discharge. Specifically, the short-circuited cell determined from the short-circuit inspection of the battery and the abnormal battery determined from the waste battery may undergo a crushing step in a specific atmosphere to prevent the risk of fire.

[0068] Specifically, the stabilization crushing step (S300) may obtain a crushed material by crushing the battery using a cryogenic crushing device. The crushing may include, as a non-limiting example, crushing the waste battery by applying physical or mechanical force and crushing it into a fine powder. In this case, by performing cryogenic crushing, the crushing step can easily crush the battery that is unable to perform electrical discharge.

[0069] In one embodiment, the temperature of the stabilization crushing step (S300) may be performed at a process temperature of 0 ℃ or lower. Specifically, the temperature may be performed at a temperature of -60 ℃ or lower. More specifically, the temperature may be performed within a temperature range that prevents the explosion of the electrolyte.

[0070] In one embodiment, the stabilization crushing step (S300) may be a crushing method using at least one of shear, compression, and tensile force. Specifically, the crushing step may be performed by, for example, at least one of a hammer mill, a ball mill, and a stirred ball mill. The hammer mill may perform at least one step of disassembly, punching, and milling, and various types of crushing or grinding devices, such as industrial grinders, may be utilized as non-limiting examples. The step of crushing the battery may separate some large impurities among impurities such as aluminum (Al), copper (Cu), iron (Fe), and plastic in the composition included in the battery.

[0071] In one embodiment, the stabilization crushing step (S300) may be performed such that the size of the battery crushed material is 100 mm or less. Specifically, the size of the battery crushed material may be 80 mm or less, more specifically, 50 mm or less. When the size of the battery crushed material satisfies the aforementioned range, there is an advantage of excellent process energy efficiency, and when the size of the battery crushed material is larger than the aforementioned range, there is an uneconomical problem due to excessive energy supply during the heat treatment step.

[0072] In one embodiment, the stabilization crushing step (S300) may be performed by supplying a liquid. The liquid can reduce the possibility of fire that may occur when crushing a module containing a short-circuited cell and reduce the residual energy of the module. For example, the liquid may be a liquid substance such as water, distilled water, liquid nitrogen, etc., supplied to prevent a fire caused by residual energy when the module is crushed.

[0073]

[0074] Preferred embodiments and comparative examples of the present invention are described below. However, the following examples are merely preferred embodiments of the present invention, and the present invention is not limited to the following examples.

[0075]

[0076] <Experimental Example> : Battery Short Circuit Testing Method

[0077] (Battery preparation stage)

[0078] The step of preparing the battery involved preparing a battery module containing 27 cells. The battery module used satisfied normal conditions.

[0079]

[0080] (Battery current application stage)

[0081] The above battery module was discharged under conditions of 3.0 to 4.2 V.

[0082]

[0083] (Step of measuring the change in the surrounding magnetic field of multiple cells)

[0084] Charging and discharging were performed on the above-mentioned battery, and at this time, a multi-channel magnetic sensor device, which is a magnetic sensor capable of measuring the magnetic field around the battery, was placed in an area where battery cells were connected in an array to scan the surrounding magnetic field. Specifically, the magnetic sensor was screened in the horizontal direction of the battery module to measure the magnetic field around a plurality of battery cells within the battery module.

[0085] At this time, the multi-channel magnetic sensor device is a device for verifying a leakage magnetic field caused by a battery short-circuit cell, and includes an electromagnet magnetizer, a coil arranged to surround a part of the electromagnet magnetizer, and a Hall sensor that detects the magnetic field of the battery generated by the magnetizer.

[0086] Using the above-described multi-channel magnetic sensor device, sensor data for each position was acquired in a unidirectional arrangement of multiple cells, and the vertical component of the magnetic flux leaking from the cell components within the battery was measured at the Hall sensor.

[0087] In addition, the voltage applied from the multi-channel magnetic sensor device, which is the magnetic sensor mentioned above, was controlled to maintain a normal reference voltage of 3.7 V.

[0088]

[0089] (Step for determining paragraphs)

[0090] After measuring the change in the surrounding magnetic field of the plurality of cells, a normal section containing normal cells and a short-circuited section containing short-circuited cells were determined through a voltage graph based on scan direction position information using a magnetic camera, which is a device for acquiring a two-dimensional image or video, or through a one-dimensional signal measuring the magnetic field leaking in the vertical direction by a single Hall sensor. Specifically, the short-circuited section was distinguished from the normal section by the strength of the magnetic field in the one-dimensional image, and distinguished from the normal section by the voltage value in the two-dimensional image.

[0091] FIG. 3 is a graph of signal results measured from a battery including a short-circuited cell according to one embodiment of the present invention.

[0092] Referring to Fig. 3, it was confirmed that in a battery containing multiple cells, the voltage is significantly reduced by the short circuit in the region containing the short-circuited cell.

[0093] FIGS. 4a to 4c are photographs and graphs showing two-dimensional scan image results of a battery including a short-circuited cell according to one embodiment of the present invention.

[0094] Referring to FIGS. 4a to 4c, FIG. 4a is a schematic diagram showing a battery containing a short-circuited cell, FIG. 4b shows two-dimensional image data of the battery containing the short-circuited cell of FIG. 4a, and FIG. 4c shows a one-dimensional signal graph of the magnetic field leaking in the vertical direction by a single Hall sensor in the yellow line portion of FIG. 4b. For a battery containing a short-circuited cell, it can be confirmed that the magnetic field around the short-circuited cell is non-uniform through a magnetic field sensor including a Hall sensor. In this way, it was confirmed that the pattern of the leakage magnetic field generated by the short circuit appears differently depending on the location.

[0095]

[0096] The present invention is not limited to the above embodiments and can be manufactured in various different forms, and those skilled in the art will understand that the invention can be implemented in other specific forms without changing the technical concept or essential features of the invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive.

Claims

1. A step of preparing a battery in which multiple cells are aligned; A step of applying current to a battery in which the plurality of cells are aligned; A step of measuring the change in the surrounding magnetic field of the plurality of cells in the direction in which the plurality of cells are aligned in the battery in which the plurality of cells are aligned; and The method includes a step of determining a normal portion containing normal cells and a short-circuited portion containing short-circuited cells among the plurality of cells through the change in the magnetic field. A short-circuit detection method for a battery in which the above normal part and the above short-circuit part are determined by the difference in signal change derived from the above magnetic field change amount.

2. In Paragraph 1, A short-circuit inspection method for a waste battery in which a plurality of cells are aligned as described above.

3. In Paragraph 2, A method for inspecting a short circuit of a battery before crushing the waste battery to recycle the waste battery.

4. In Paragraph 1, The step of applying current to the battery in which the plurality of cells are aligned is, A short-circuit test method for a battery that performs charging and discharging in the range of 3.0 to 4.2 V on the above battery.

5. In Paragraph 1, The step of measuring the change in the surrounding magnetic field of the plurality of cells in the direction in which the plurality of cells are aligned in the battery in which the plurality of cells are aligned is: A short-circuit detection method for a battery that measures at least one of the electric field and magnetic field surrounding a battery in which a plurality of cells are aligned using a magnetic sensor.

6. In Paragraph 1, A short-circuit detection method for a battery in which the above signal change determines at least one non-uniform section as the short-circuit section from the one-dimensional or two-dimensional result values ​​derived from the above normal section and the above short-circuit section.

7. In Paragraph 1, A short-circuit inspection method for a battery in which the above-mentioned short-circuit portion has a voltage value that is 2 V or lower than the above-mentioned normal portion in terms of the amount of change of the above-mentioned magnetic field.

8. In Paragraph 6, A short-circuit inspection method for a battery in which the change in the above magnetic field is acquired as a one-dimensional or two-dimensional image.

9. In Paragraph 5, A short-circuit detection method for a battery in which the magnetic sensor scans the magnetic sensor in any one of the horizontal, vertical, and height directions and measures the amount of change in the magnetic field.

10. In Paragraph 1, A short-circuit inspection method for a battery that determines the region satisfying the following Equation 1 in the change amount of the above magnetic field as the short-circuit portion. <Equation 1> A - B ≥ 2.0 V (In the above Equation 1, A represents the target voltage value set during the step of applying current to a battery in which multiple cells are aligned, and B represents the voltage value of a specific cell in the change of the surrounding magnetic field of the multiple cells.) 11. A method for processing batteries for recycling waste batteries in which multiple cells are aligned, A short-circuit inspection step of a battery for determining a short-circuited cell among the plurality of cells above; A step of determining that a battery module selected from the short-circuit inspection of the above battery is an abnormal battery module; The method includes the step of stabilizing and crushing the above-mentioned abnormal battery module, and The short-circuit test step of the battery above is, Step of preparing a battery in which multiple cells are aligned; A step of applying current to a battery in which the plurality of cells are aligned; A step of measuring the change in the surrounding magnetic field of the plurality of cells in the direction in which the plurality of cells are aligned in the battery in which the plurality of cells are aligned; and A method for processing a battery comprising the step of determining a normal portion containing a normal cell and a short-circuited portion containing a short-circuited cell among the plurality of cells through the amount of change in the magnetic field.

12. In Paragraph 11, A method for handling a battery in which the above short-circuit section has a voltage value 2.5 to 3.7 V lower than the above normal section in terms of the amount of change of the above magnetic field.

13. In Paragraph 11, A method for processing a battery that determines the region satisfying the following Equation 1 in the change amount of the above magnetic field as the above short-circuit portion. <Equation 1> A - B ≥ 2.0 V (In the above Equation 1, A represents the target voltage value set during the step of applying current to a battery in which multiple cells are aligned, and B represents the voltage value of a specific cell in the change of the surrounding magnetic field of the multiple cells.) 14. In Paragraph 11, A method for processing a battery, wherein the step of measuring the change in the surrounding magnetic field of the plurality of cells involves moving a magnetic sensor along either a first direction in which the plurality of cells are arranged or a second direction which is perpendicular to the first direction and the horizontal plane thereof, and measuring the change in the magnetic field.

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