Battery inspection device and battery manufacturing equipment

Abstract

A battery inspection device according to the present invention comprises: a test current application unit for applying a test current of a preset intensity to a battery in an idle state; and a control unit for adjusting the intensity of the test current in response to a voltage change in the battery that occurs while the test current is being applied, and thereby reducing the voltage change in the battery.

Description

Battery inspection device and battery manufacturing equipment

[0001] The present application carries a claim of priority based on Korean Patent Application No. 10-2024-0191572 filed on December 19, 2024 and Korean Patent Application No. 10-2025-0184043 filed on November 27, 2025, and all contents disclosed in the specifications and drawings of said patent applications are incorporated by reference into the present application.

[0002] The present invention relates to a battery inspection device and battery manufacturing equipment, and more specifically, to a battery inspection device for inspecting whether a rechargeable battery has defects, and battery manufacturing equipment including such a battery inspection device.

[0003] Recently, as rechargeable batteries—that is, secondary batteries—are widely applied not only to small devices such as mobile phones, camcorders, and laptop computers, but also to large devices requiring high output voltage and large charging capacity, such as electric vehicles and Energy Storage Systems (ESS), various types of batteries are being mass-produced. Consequently, interest and demand for battery inspection technology that can shorten battery manufacturing and inspection times and increase manufacturing efficiency are increasing.

[0004] However, existing technology has the problem that batteries that have undergone the formation process and high-temperature aging process among battery manufacturing processes are placed in a separate chamber or aging rack equipped with an air conditioner, and after measuring the voltage of each battery while performing room-temperature aging for a period of 3 to 15 days, the defect status of the battery is determined based on the voltage drop of each battery, which requires a long time for cooling and inspection of the batteries and reduces manufacturing efficiency.

[0005] The technical problem that the present invention aims to solve is to provide a battery inspection device that shortens battery inspection time and improves battery manufacturing efficiency, and a battery manufacturing equipment including such a battery inspection device.

[0006] A battery inspection device according to one embodiment of the present invention comprises: a test current application unit that applies a test current of a predetermined intensity to a battery in a resting state; and a control unit that reduces the amount of voltage change of the battery by adjusting the intensity of the test current in response to a voltage change of the battery occurring while the test current is applied, wherein the control unit is configured to determine whether the battery has a defect based on the adjusted intensity of the test current if, during a predetermined time after the test current of the adjusted intensity is applied, the amount of voltage change of the battery does not exceed a predetermined allowable value.

[0007] In one embodiment, the control unit may be configured to monitor the voltage of the battery using at least one voltage sensor while the test current is applied.

[0008] In one embodiment, the control unit may be configured to increase the intensity of the test current in response to the voltage difference between the reference voltage and the voltage of the battery when the voltage of the battery becomes lower than a predetermined reference voltage over time.

[0009] In one embodiment, the control unit may be configured to reduce the intensity of the test current in response to the voltage difference between the reference voltage and the voltage of the battery when the voltage of the battery becomes higher than a predetermined reference voltage over time.

[0010] In one embodiment, the control unit may be configured to determine whether the battery is defective by comparing the regulated intensity of the test current with a predetermined reference intensity.

[0011] In one embodiment, the battery inspection device may further include a cooling jig that contacts the battery and cools the battery.

[0012] In one embodiment, the cooling jig may include a plurality of cooling plates that are in contact with the battery, each having a cooling channel configured to allow a cooling fluid to pass through it.

[0013] In one embodiment, the cooling jig may further include a pressurizing unit configured to press the plurality of cooling plates toward the battery side.

[0014] In one embodiment, the cooling jig may further include a load cell that measures the load applied to the battery by the pressurizing unit.

[0015] In one embodiment, the cooling jig may further include a distribution unit that distributes the cooling fluid to the plurality of cooling plates and introduces the cooling fluid into the cooling channels of each of the plurality of cooling plates.

[0016] In one embodiment, at least one of the plurality of cooling plates has a plurality of mutually independent cooling channels, and the distribution unit may include a plurality of manifolds corresponding to each of the plurality of cooling channels.

[0017] In one embodiment, the distribution unit may further include a plurality of delivery pipes that deliver a cooling fluid supplied from a chiller to each of the plurality of manifolds; and an opening / closing unit configured to selectively open or close the plurality of delivery pipes.

[0018] In one embodiment, the test current application unit may be configured to apply the test current after the battery in contact with the cooling jig has been cooled to a predetermined target temperature.

[0019] In one embodiment, the cooling jig may be configured to cool the battery until the temperature of the battery reaches a target temperature set in a range of 0°C or higher and 23°C or in a range of 0°C or higher and 15°C.

[0020] A battery manufacturing device according to another aspect of the present invention includes the battery inspection device described above.

[0021] According to one embodiment of the present invention, a test current that can be implemented as a microcurrent and is capable of precise control is applied to a battery in a resting state, and since the defect of the battery is determined based on the intensity of the test current controlled in response to the voltage change of the battery, the battery inspection time can be shortened while the accuracy and reliability of the inspection results can be improved.

[0022] In addition, according to one embodiment of the present invention, since the battery is cooled by direct contact with a cooling jig and the test current is applied to the battery in a cooled state, the temperature stabilization time and inspection time of the battery heated during the battery manufacturing process can be further shortened and the battery manufacturing efficiency can be improved.

[0023] In addition, according to one embodiment of the present invention, a plurality of mutually independent cooling channels are provided within the cooling plate of a cooling jig that comes into contact with a battery, so that the amount of cooling fluid flowing into the cooling plate can be easily adjusted according to the target cooling temperature, type, size, etc. of the battery to be inspected.

[0024] Furthermore, a person skilled in the art to which the present invention pertains will readily understand from the following description that various embodiments according to the present invention can solve various technical problems not mentioned above.

[0025] FIG. 1 is a block diagram showing a battery inspection device according to one embodiment of the present invention.

[0026] FIG. 2 is a perspective view showing a cooling jig of a battery inspection device according to one embodiment of the present invention.

[0027] FIG. 3 is a top view showing the cooling jig illustrated in FIG. 2.

[0028] FIG. 4 is a drawing showing an example of a cooling plate applicable to the present invention.

[0029] Figure 5 is a diagram showing the battery pressurization method of the cooling jig illustrated in Figure 2.

[0030] FIG. 6 is a drawing showing another example of a cooling plate applicable to the present invention.

[0031] Figure 7 is a diagram showing the connection state between the cooling plate and the distribution unit illustrated in Figure 6.

[0032] FIG. 8 is a block diagram showing a control unit of a battery inspection device according to one embodiment of the present invention.

[0033] FIG. 9 is a flowchart illustrating the inspection process of a battery inspection device according to one embodiment of the present invention.

[0034] Figure 10 is a graph showing the change in leakage current of the battery over time.

[0035] Figure 11 is a graph showing the change in the difference in leakage current between a good battery and a defective battery over time.

[0036] FIG. 12 is a block diagram showing battery manufacturing equipment according to one embodiment of the present invention.

[0037] Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings to clarify solutions corresponding to the technical problems of the present invention. However, in describing the present invention, if a description of related prior art would obscure the gist of the present invention, such description may be omitted.

[0038] Furthermore, the terms used in this specification are defined considering their functions in the present invention, and these may vary depending on the intentions or practices of the designer, manufacturer, etc. Therefore, the definitions of the terms described below should be based on the content throughout this specification.

[0039] In addition, it should be noted in advance that, unless otherwise stated, various embodiments related to different components of the present invention may be combined with one another depending on the circumstances, provided that there is no technical conflict.

[0040] FIG. 1 is a block diagram showing a battery inspection device according to one embodiment of the present invention.

[0041] As illustrated in FIG. 1, a battery inspection device (100) according to one embodiment of the present invention includes a test current application unit (120) and a control unit (130).

[0042] The above test current application unit (120) is configured to apply a test current of a predetermined intensity to a battery in a resting state in which charging and discharging are not taking place.

[0043] The test current applied to the battery under test can be implemented as a microcurrent. The initial intensity of this test current can be set differently depending on the type, size, performance, etc. of the battery under test. For example, the initial intensity of the test current can be set within a range from tens of nA to tens of μA.

[0044] It should be noted that the test current provided by the test current application unit (120) is different from the charging current provided by the charger. That is, the charging current provided by the charger has a strength of tens of mA to several A and is provided for charging a discharged battery, whereas the test current provided by the test current application unit (120) is a microcurrent having a strength of tens of nA to tens of μA and is applied to a battery in a resting state where charging and discharging are not taking place.

[0045] The control unit (130) is configured to reduce the amount of voltage change of the battery by adjusting the intensity of the test current in response to the voltage change of the battery that occurs while the test current is applied.

[0046] The control unit (130) is configured to determine whether the battery is defective based on the regulated intensity of the test current, if the amount of voltage change of the battery that occurs during a predetermined time after the regulated intensity test current is applied does not exceed a predetermined allowable value, or if the voltage of the battery maintains a stable current voltage level during the predetermined time after the regulated intensity test current is applied.

[0047] The allowable value of the voltage change and the predetermined time during which the battery must maintain the current voltage level can be determined experimentally. For example, the allowable value and the predetermined time can be determined based on the results of monitoring the voltage changes of the good batteries while self-discharging the good batteries.

[0048] The battery subject to inspection in the present invention is a rechargeable battery in a state of storing electrical energy.

[0049] In addition, the battery subject to inspection according to the present invention may include an electrode assembly formed by stacking a positive electrode and a negative electrode with a separator in between, an electrolyte material, and a case accommodating the electrode assembly and the electrolyte material. Furthermore, the battery may be a battery that has undergone a formation process and an aging process after assembly is complete.

[0050] In one embodiment, the battery inspection device (100) may further include a cooling jig (110).

[0051] The above cooling jig (110) may be configured to fix the battery to be inspected and to cool the battery by contacting it.

[0052] As will be explained again below, the cooling jig (110) may include a plurality of cooling plates in contact with the battery. Additionally, the cooling jig (110) may be configured to fix and cool a plurality of batteries simultaneously.

[0053] The above test current application unit (120) may be configured to apply the test current after the battery in contact with the cooling jig (110) has been cooled to a predetermined target temperature.

[0054] In one embodiment, the test current application unit (120) may include a current source (not shown) that provides a test current and a connector (not shown) that electrically connects the current source to the electrode lead of the battery.

[0055] As previously mentioned, the control unit (130) is configured to adjust the intensity of the test current in response to the amount of voltage change of the battery that occurs while the test current is applied to the battery.

[0056] For example, the control unit (130) may increase the intensity of the test current in response to the voltage difference between the reference voltage and the voltage of the battery when the voltage of the battery decreases below a predetermined reference voltage over time. For example, the control unit (130) may gradually increase the intensity of the test current until the voltage of the battery reaches the reference voltage.

[0057] Additionally, the control unit (130) may reduce the intensity of the test current in response to the voltage difference between the reference voltage and the voltage of the battery when the voltage of the battery increases above a predetermined reference voltage over time. For example, the control unit (130) may gradually reduce the intensity of the test current until the voltage of the battery reaches the reference voltage.

[0058] The above reference voltage may be the initial voltage of the battery measured before the test current is applied, or a voltage determined in advance through an experiment.

[0059] In order to adjust the intensity of the test current according to the amount of voltage change of the battery, the control unit (130) can monitor the voltage of the battery using at least one voltage sensor while the test current is applied.

[0060] Additionally, the control unit (130) can determine whether the battery is defective based on the regulated intensity of the test current if the amount of voltage change of the battery that occurs during a predetermined time after the regulated intensity of the test current is applied does not exceed a predetermined allowable value, or if the voltage of the battery maintains a stable current voltage level during the predetermined time after the regulated intensity of the test current is applied.

[0061] For example, the control unit (130) can determine whether the battery is defective by comparing the controlled intensity of the test current with a predetermined reference intensity. The reference intensity may be the final intensity of the controlled test current applied to a good battery.

[0062] Generally, even when a charged battery is not in use, a voltage drop occurs due to self-discharge. Furthermore, defective batteries, in which foreign substances have infiltrated during the assembly process or the separator has been damaged, experience internal short circuits, resulting in a greater voltage drop compared to good batteries.

[0063] That is, if the above battery is a defective battery, the intensity of the test current applied to the battery until the voltage of the battery reaches the reference voltage becomes greater than the intensity of the test current applied to a good battery.

[0064] Accordingly, the control unit (130) can determine whether the battery is defective based on the intensity of the test current applied to the battery.

[0065] Such a control unit (130) may be implemented as a combination of a processor and a program executed by such a processor. Additionally, the control unit (130) may be implemented as a single processor or as two or more interoperable processors.

[0066] In one embodiment, the battery inspection device (100) may further include a chiller (140). In this case, the chiller (140) may be configured to supply cooling fluid to the cooling jig (110).

[0067] FIG. 2 is a perspective view showing a cooling jig of a battery inspection device according to one embodiment of the present invention.

[0068] As illustrated in FIG. 2, a cooling jig (110) of a battery inspection device (100) according to one embodiment of the present invention may include a plurality of cooling plates (112), a pressurizing unit (114), and a distribution unit (116).

[0069] The plurality of cooling plates (112) may be configured to come into contact with the battery (2) to be inspected and cool the battery (2). To this end, each cooling plate (112) may be provided with a cooling channel configured to allow a cooling fluid to pass through it.

[0070] The above-mentioned pressurizing unit (114) may be configured to press a plurality of cooling plates (112) toward the battery (2).

[0071] The distribution unit (116) may be configured to distribute a cooling fluid supplied from a chiller (140) to the plurality of cooling plates (112) and to introduce the cooling fluid into the cooling channels of each cooling plate (112). To this end, the distribution unit (116) may include a manifold (Mi1) and a plurality of tubes (Ti1).

[0072] The above manifold (Mi1) may have a main connection pipe connected to the supply pipe (142) of the chiller (140), and a plurality of sub-connection pipes branched from the main connection pipe and each connected to the plurality of cooling plates (112).

[0073] The plurality of tubes (Ti1) above may be configured to connect the plurality of sub-connecting pipes of the manifold (Mi1) and the plurality of cooling plates (112) in a one-to-one manner.

[0074] As previously mentioned, a battery inspection device (100) according to one embodiment of the present invention may include a chiller (140). This chiller (140) may be configured to supply cooling fluid to a distribution unit (116) through a supply pipe (142), and to recover the cooling fluid discharged after passing through the cooling channels of each cooling plate (112) through a recovery pipe (144) to cool it again.

[0075] This cooling jig (110) may be configured to cool the battery until the temperature of the battery to be tested reaches a target temperature set in the range of 0°C to 23°C or 0°C to 15°C.

[0076] FIG. 3 is a top view showing the cooling jig (110) illustrated in FIG. 2.

[0077] As illustrated in FIG. 3, the cooling jig (110) may be configured to simultaneously fix and cool a plurality of batteries (2). To this end, the cooling jig (110) may include a plurality of cooling plates (112) arranged side by side in one direction (X-axis direction). A plurality of batteries (2) may be placed between the plurality of cooling plates (112).

[0078] Additionally, the cooling jig (110) may include a distribution unit (116) that distributes cooling fluid to a plurality of cooling plates (112).

[0079] This distribution unit (116) may include an input manifold (Mi1) for distributing a cooling fluid to a plurality of cooling plates (112), and a plurality of input tubes (Ti1) connecting the input manifold (Mi1) to the plurality of cooling plates (112).

[0080] Additionally, the distribution unit (116) may include an output manifold (Mo1) for recovering cooling fluid discharged from a plurality of cooling plates (112), and a plurality of output tubes (To1) connecting the output manifold (Mo1) to the plurality of cooling plates (112).

[0081] In one embodiment, the cooling jig (110) may include a load cell (118). In this case, the load cell (112) may be configured to measure the load applied to the battery (2) by the pressurizing unit (114).

[0082] FIG. 4 is a drawing showing an example of a cooling plate applicable to the present invention.

[0083] As illustrated in FIG. 4, each cooling plate (112) of the cooling jig (110) may have a cooling channel (C1) provided therein. Additionally, the cooling plate (112) may have an inlet (I1) for introducing cooling fluid into the cooling channel (C1) and an outlet (o1) for discharging the cooling fluid that has passed through the cooling channel (C1) to the outside of the cooling plate (112).

[0084] Additionally, the cooling plate (112) may be provided with a guide hole (h1) through which the guide rail of the pressurizing unit (114), described later, passes.

[0085] Figure 5 is a diagram showing the battery pressurization method of the cooling jig illustrated in Figure 2.

[0086] As illustrated in FIG. 5, when a battery (2) is placed between a plurality of cooling plates (112), the pressurizing unit (114) of the cooling jig (110) can press the plurality of cooling plates (112) toward the battery (2) to apply a load to each battery (2).

[0087] In this case, each cooling plate (112) may be equipped with a stopper (S1). This stopper (S1) may be configured to protrude from one side of the cooling plate (112) facing the battery (2) to support the battery (2) and prevent the gap between the cooling plates from becoming narrower than necessary.

[0088] In one embodiment, the pressure unit (114) may include a pressure plate (F1), a guide rail (F2), a support frame (F3), and a pressure handle (F4).

[0089] The above pressure plate (F1) may be configured to make surface contact with the cooling plate positioned at the outermost of the plurality of cooling plates (112).

[0090] The guide rail (F2) can be configured to extend in the arrangement direction (X-axis direction) of the cooling plates through the guide hole (h1) of the cooling plate (112) described with reference to FIG. 4, and to guide the movement of each cooling plate (112) and the pressure plate (F1).

[0091] The support frame (F3) above may be configured to support the guide rail (F2) and the pressure handle (F4) described later.

[0092] The above pressure handle (F4) may be configured to move the pressure plate (F1) toward the cooling plate (112) by rotating it clockwise or counterclockwise. This pressure handle (F4) may be configured to be rotated manually by an operator, or configured to be rotated automatically by an actuator or a servo motor, etc.

[0093] The load applied to each battery (2) by this pressurizing unit (114) can be adjusted by referring to the measurement value of the load cell (112). For example, the load applied to each battery (2) can be adjusted to a range of 0 to 1000 [kgf].

[0094] FIG. 6 is a drawing showing another example of a cooling plate applicable to the present invention.

[0095] As illustrated in FIG. 6, at least one cooling plate (112A) among a plurality of cooling plates provided in a cooling jig (110) may have a plurality of mutually independent cooling channels (C1, C2). In this case, the cooling plate (112A) may include a plurality of inlets (I1, I2) and a plurality of outlets (o1, o2) corresponding to each of the plurality of cooling channels (C1, C2).

[0096] For example, two cooling channels (C1, C2) may be provided inside the cooling plate (112A). In this case, the cooling plate (112A) may include a first inlet (I1) for introducing cooling fluid into the first cooling channel (C1) among the two cooling channels (C1, C2), a second inlet (I2) for introducing cooling fluid into the second cooling channel (C2), a first outlet (o1) for discharging cooling fluid that has passed through the first cooling channel (C1), and a second outlet (o2) for discharging cooling fluid that has passed through the second cooling channel (C2).

[0097] FIG. 6 illustrates an embodiment in which two mutually independent cooling channels (C1, C2) are provided inside the cooling plate (112), but according to the embodiment, three or more mutually independent cooling channels may be provided inside the cooling plate (112).

[0098] Figure 7 is a diagram showing the connection state between the cooling plate and the distribution unit illustrated in Figure 6.

[0099] As illustrated in FIG. 7, when the cooling plate (112A) has a plurality of cooling channels (C1, C2), the distribution unit (116) of the cooling jig (110) may include a plurality of manifolds corresponding to each of the plurality of cooling channels (C1, C2).

[0100] For example, the distribution unit (116) may include a first input manifold (Mi1) that provides cooling fluid to the first cooling channel (C1) and a second input manifold (Mi2) that provides cooling fluid to the second cooling channel (C2).

[0101] Additionally, the distribution unit (116) may include a plurality of delivery pipes that deliver cooling fluid supplied from the chiller (140) to the plurality of manifolds. For example, it may include a first delivery pipe (D1) and a second delivery pipe (D2) that deliver cooling fluid supplied through the supply pipe (142) of the chiller (140) to the first input manifold (Mi1) and the second input manifold (Mi2), respectively.

[0102] In this case, the distribution unit (116) may further include an opening / closing unit (V1) configured to selectively open or close the plurality of delivery pipes. This opening / closing unit (V1) may include a plurality of valves that each open or close the plurality of delivery pipes.

[0103] Additionally, the distribution unit (116) may include a first input tube (Ti1) connecting the first input manifold (Mi1) and the first inlet (I1) of the cooling plate (112A), and a second input tube (Ti2) connecting the second input manifold (Mi2) and the second inlet (I2) of the cooling plate (112A).

[0104] When the above cooling jig (110) includes a plurality of cooling plates (112A) each having a plurality of cooling channels, the distribution unit (116) may, in correspondence with this, include a plurality of first input tubes (Ti1) and a plurality of second input tubes (Ti2).

[0105] In one embodiment, the distribution unit (116) may further include a first output manifold (Mo1) for collecting cooling fluid discharged from the first cooling channel (C1) and a second output manifold (Mo2) for collecting cooling fluid discharged from the second cooling channel (C2).

[0106] In this case, the distribution unit (116) may include a first output tube (To1) connecting the first outlet (o1) of the cooling plate (112A) to the first output manifold (Mo1), and a second output tube (To2) connecting the second outlet (o2) of the cooling plate (112A) to the second output manifold (Mo2).

[0107] In this way, by providing a plurality of mutually independent cooling channels within the cooling plate that comes into contact with the battery under inspection, the amount of cooling fluid flowing into the cooling plate can be easily adjusted according to the target cooling temperature, type, size, etc. of the battery under inspection.

[0108] FIG. 8 is a block diagram showing a control unit of a battery inspection device according to one embodiment of the present invention.

[0109] As illustrated in FIG. 8, the control unit (130) may include a cooling control module (132), a monitoring module (134), a test current control module (136), and a discrimination module (138).

[0110] The cooling control module (132) can cool the battery to a predetermined target temperature by controlling the chiller (140) to supply cooling fluid to the cooling plates (112, 112A) of the cooling jig (110) after the battery is mounted on the cooling jig (110). In this case, the target temperature may be set in a range of 0°C or higher and 23°C or in a range of 0°C or higher and 15°C.

[0111] Table 1 below shows the time required for battery testing according to battery temperature. In Table 1, 'X' indicates that the test has not been completed, and 'O' indicates that the test has been completed.

[0112] Test Time [h] Battery Temperature [℃] 23 20 15 10 5 0 0.5 XLOX 0 1.0 XLOX 0 1.5 XLOX 0 2.0 XLOX 0 2.5 XLOX 0 3.0 XLOX 0

[0113] As shown in Table 1, when the battery temperature falls within the range of 20°C or higher and 23°C or lower, the amount of self-discharge of the battery is relatively higher than when the battery temperature is below 20°C, so it takes about 4 hours to stabilize the battery voltage and determine whether the battery is defective. Therefore, if the battery is cooled so that the battery temperature is lowered to the range of 0°C or higher and 15°C or lower, the battery inspection time can be further shortened. On the other hand, if the battery temperature exceeds 23°C, the amount of self-discharge of the battery increases, and the battery inspection time increases rapidly. In addition, lowering the battery temperature to below 0°C requires a separate cooling facility in addition to the cooling jig (110), which increases the battery inspection cost and reduces manufacturing efficiency.

[0114] The monitoring module (134) can monitor the voltage of the battery using at least one voltage sensor while the test current of the test current application unit (120) is applied to the battery.

[0115] The above test current control module (136) is configured to reduce the amount of voltage change of the battery by controlling the intensity of the test current in response to the voltage change of the battery that occurs while the test current is applied.

[0116] For example, if the voltage of the battery decreases below a predetermined reference voltage over time, the test current control module (136) can increase the intensity of the test current in response to the voltage difference between the reference voltage and the voltage of the battery. For example, the test current control module (136) can gradually increase the intensity of the test current until the voltage of the battery reaches the reference voltage.

[0117] On the other hand, if the voltage of the battery increases above a predetermined reference voltage over time, the test current control module (136) may reduce the intensity of the test current or stop the application of the test current in response to the voltage difference between the reference voltage and the voltage of the battery. For example, the test current control module (136) may gradually reduce the intensity of the test current until the voltage of the battery reaches the reference voltage.

[0118] The above reference voltage may be the initial voltage of the battery measured before the test current is applied, or a voltage determined in advance through an experiment.

[0119] The above determination module (138) can inspect the battery based on the controlled intensity of the test current if the amount of voltage change of the battery that occurs during a predetermined time after the controlled intensity test current is applied does not exceed a predetermined allowable value, that is, if the voltage of the battery maintains a stable current voltage level during the predetermined time after the controlled intensity test current is applied.

[0120] For example, the above determination module (138) can determine whether the battery is defective by comparing the controlled intensity of the test current with a predetermined reference intensity. In this case, the reference intensity can be determined experimentally. For example, the reference intensity may be the final intensity of the controlled test current applied to a good battery.

[0121] The above-described cooling control module (132), monitoring module (134), test current control module (136), and determination module (138) can be implemented as a combination of at least one processor and a program executed by at least one processor.

[0122] FIG. 9 is a flowchart illustrating the inspection process of a battery inspection device according to one embodiment of the present invention.

[0123] As illustrated in FIG. 9, after the battery is mounted on the cooling jig (110), the control unit (130) of the battery inspection device (100) can cool the battery to a target temperature by controlling the chiller (140) to supply cooling fluid to the cooling plates (112, 112A) of the cooling jig (110) (S910). As previously mentioned, the target temperature can be set in a range of 0°C or higher and 23°C or in a range of 0°C or higher and 15°C.

[0124] The control unit (130) can determine whether the temperature of the battery has reached a target temperature using at least one temperature sensor (S920).

[0125] When the temperature of the battery reaches the target temperature, the control unit (130) controls the test current application unit (120) to apply a test current of a predetermined intensity to the battery (S930).

[0126] While a test current is applied to the battery, the control unit (130) can monitor the voltage of the battery using at least one voltage sensor (S940).

[0127] When a change occurs in the voltage of the battery and the voltage level of the battery deviates from a predetermined allowable value, the control unit (130) can reduce the amount of voltage change of the battery by adjusting the intensity of the test current in response to the amount of voltage change of the battery (S950, S960, S970).

[0128] For example, if the voltage of the battery decreases below a predetermined reference voltage over time, the control unit (130) may increase the intensity of the test current in response to the voltage difference between the reference voltage and the voltage of the battery. For example, the control unit (130) may gradually increase the intensity of the test current until the voltage of the battery reaches the reference voltage.

[0129] On the other hand, if the voltage of the battery increases above a predetermined reference voltage over time, the control unit (130) may reduce the intensity of the test current in response to the voltage difference between the reference voltage and the voltage of the battery. For example, the control unit (130) may gradually reduce the intensity of the test current until the voltage of the battery reaches the reference voltage.

[0130] The above reference voltage may be the initial voltage of the battery measured before the test current is applied, or a voltage determined in advance through an experiment.

[0131] If the amount of voltage change of the battery that occurs during a predetermined time after the test current of the intensity adjusted as described above is applied to the battery does not exceed a predetermined allowable value, that is, if the voltage of the battery maintains a stable current voltage level during the predetermined time after the test current of the intensity adjusted as described above is applied, the control unit (130) can inspect the battery based on the intensity of the test current adjusted as described above (S980).

[0132] For example, the control unit (130) can determine whether the battery is defective by comparing the controlled intensity of the test current with a predetermined reference intensity. The reference intensity may be the final intensity of the controlled test current applied to a good battery.

[0133] Figure 10 is a graph showing the change in leakage current of the battery over time.

[0134] As shown in Fig. 10, leakage current occurs in both the good battery and the defective battery, but over time, the leakage current of the defective battery increases more than the leakage current of the good battery. This is because additional leakage current is generated in the defective battery due to an internal short circuit.

[0135] Figure 11 is a graph showing the change in the difference in leakage current between a good battery and a defective battery over time.

[0136] As shown in Fig. 11, when the temperature of the good battery and the defective battery is 25°C, the difference in leakage current value (ΔLeak Current) between the good battery and the defective battery does not show a clear trend of change during the elapsed two hours. Therefore, the time required to determine whether the battery is defective increases relatively.

[0137] On the other hand, when the temperature of the good battery and the defective battery is 10℃ each, the difference in leakage current between the good battery and the defective battery shows a clear increasing trend over two hours. Therefore, the time required to determine whether the battery is defective is relatively reduced.

[0138] FIG. 12 is a block diagram showing battery manufacturing equipment according to one embodiment of the present invention.

[0139] As illustrated in FIG. 12, a battery manufacturing device (10) according to one embodiment of the present invention includes the battery inspection device (100) described above. In this case, the battery inspection device (100) can cool and inspect batteries that have been assembled and activated through a battery manufacturing process.

[0140] In one embodiment, the battery manufacturing equipment (10) may further include an aging device (200). The aging device (200) may be configured to age the batteries at a high temperature of 50°C or higher before an inspection by the battery inspection device (100) is performed. To this end, the aging device (200) may include a chamber that accommodates the batteries inside and a temperature control device that controls the internal temperature of the chamber.

[0141] In one embodiment, the battery manufacturing equipment (10) may further include a formation device (300). The formation device (300) may be configured to activate the batteries by repeatedly charging and discharging them before aging is performed by the aging device (200). To this end, the formation device (300) may include a charger for charging the batteries and a discharger for discharging the charged batteries.

[0142] In one embodiment, the battery manufacturing equipment (10) may further include a battery assembly device (400). The battery assembly device (400) may be configured to manufacture the batteries by housing an electrolyte material in a case and sealing the case, and forming an electrode assembly in which a positive electrode and a negative electrode are stacked with a separator in between.

[0143] As described above, according to one embodiment of the present invention, a test current that can be implemented as a microcurrent and is capable of precise control is applied to a battery in a resting state, and since the defect of the battery is determined based on the intensity of the test current controlled in response to the voltage change of the battery, the battery inspection time can be shortened while the accuracy and reliability of the inspection results can be improved.

[0144] In addition, according to one embodiment of the present invention, since the battery is cooled by direct contact with a cooling jig and the test current is applied to the battery in a cooled state, the temperature stabilization time and inspection time of the battery heated during the battery manufacturing process can be further shortened and the battery manufacturing efficiency can be improved.

[0145] In addition, according to one embodiment of the present invention, a plurality of mutually independent cooling channels are provided within the cooling plate of a cooling jig that comes into contact with a battery, so that the amount of cooling fluid flowing into the cooling plate can be easily adjusted according to the target cooling temperature, type, size, etc. of the battery to be inspected.

[0146] Furthermore, it goes without saying that the embodiments according to the present invention can solve various other technical problems in the relevant technical field as well as related technical fields other than those mentioned in this specification.

[0147] The present invention has been described above with reference to specific embodiments. However, those skilled in the art will clearly understand that various modified embodiments may be implemented within the technical scope of the present invention. Therefore, the embodiments disclosed above should be considered in an illustrative rather than a restrictive sense. That is, the true technical scope of the present invention is set forth in the claims, and all variations within the scope of equivalents should be interpreted as being included in the present invention.

[0148] [Explanation of the symbol]

[0149] 10: Battery Manufacturing Equipment

[0150] 100: Battery Inspection Device

[0151] 110: Cooling Jig

[0152] 112, 112A: Cooling plate

[0153] 114: Pressurization unit

[0154] 116: Distribution Unit

[0155] 118: Load cell

[0156] 120: Test current application unit

[0157] 130: Control Unit

[0158] 132: Cooling control module

[0159] 134: Monitoring Module

[0160] 136: Test current regulation module

[0161] 138: Discrimination Module

[0162] 140: Chiller

Claims

1. A test current application unit that applies a test current of a predetermined intensity to a battery in a resting state; and It includes a control unit that reduces the amount of voltage change of the battery by adjusting the intensity of the test current in response to the voltage change of the battery that occurs while the test current is applied. A battery inspection device configured such that the above control unit determines whether the battery is defective based on the above-mentioned intensity of the test current if, during a predetermined time after a test current of the above-mentioned intensity is applied, the amount of voltage change of the battery does not exceed a predetermined allowable value.

2. In Paragraph 1, A battery testing device characterized in that the control unit is configured to monitor the voltage of the battery using at least one voltage sensor while the test current is applied.

3. In Paragraph 1, A battery testing device characterized by the above-described control unit being configured to increase the intensity of the test current in response to the voltage difference between the reference voltage and the voltage of the battery when the voltage of the battery drops below a predetermined reference voltage over time.

4. In Paragraph 1, A battery inspection device characterized by the above-described control unit being configured to reduce the intensity of the test current in response to the voltage difference between the reference voltage and the voltage of the battery when the voltage of the battery becomes higher than a predetermined reference voltage over time.

5. In Paragraph 1, A battery inspection device characterized by the above-described control unit being configured to determine whether the battery is defective by comparing the adjusted intensity of the above-described test current with a predetermined reference intensity.

6. In Paragraph 1, A battery inspection device characterized by further including a cooling jig that cools the battery by contacting the battery.

7. In Paragraph 6, The above cooling jig is, A battery inspection device characterized by comprising a plurality of cooling plates in contact with the battery, each having a cooling channel configured to allow a cooling fluid to pass through its interior.

8. In Paragraph 7, The above cooling jig is, A battery inspection device characterized by further including a pressurizing unit configured to pressurize the plurality of cooling plates toward the battery side.

9. In Paragraph 8, The above cooling jig is, A battery inspection device characterized by further including a load cell that measures the load applied to the battery by the above-mentioned pressurizing unit.

10. In Paragraph 7, The above cooling jig is, A battery inspection device characterized by further including a distribution unit that distributes the cooling fluid to the plurality of cooling plates and introduces the cooling fluid into the cooling channels of each of the plurality of cooling plates.

11. In Paragraph 10, At least one of the plurality of cooling plates has a plurality of mutually independent cooling channels, and A battery inspection device characterized in that the above distribution unit includes a plurality of manifolds corresponding to each of the plurality of cooling channels.

12. In Paragraph 11, The above distribution unit is, A plurality of delivery pipes that deliver a cooling fluid supplied from a chiller to each of the plurality of manifolds; and A battery inspection device characterized by further including an opening / closing unit configured to selectively open or close the plurality of transmission tubes.

13. In Paragraph 6, A battery inspection device characterized in that the above test current application unit is configured to apply the test current after the battery in contact with the cooling jig is cooled to a predetermined target temperature.

14. In Paragraph 6, A battery inspection device characterized by the above cooling jig being configured to cool the battery until the temperature of the battery reaches a target temperature set within a range of 0°C or higher and 23°C or within a range of 0°C or higher and 15°C.

15. Battery manufacturing equipment including a battery inspection device according to paragraphs 1 through 14.

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