Apparatus and method for inspecting secondary battery
By designing a checking device that includes pressure, current and temperature measurement functions, the problem of difficulty in detecting secondary battery contamination in the prior art is solved, and a rapid and accurate evaluation of the functional status of secondary battery is achieved.
Patent Information
- Application Number
- CN202380054998.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2022-07-19
- Filing Date
- 2023-07-18
- Publication Date
- 2025-03-28
AI Technical Summary
The prior art is difficult to detect contaminants inside secondary batteries quickly and accurately, especially under the influence of temperature changes.
An inspection device is designed, including a fixed support element, a movable element, a pressing element, a driving unit, a pressure measuring unit, a current control unit and a temperature sensor. The device detects defects of the secondary battery by applying pressure and voltage, measuring current and temperature, and in combination with correcting current values.
It realizes rapid and accurate detection of pollutants inside the secondary battery, and can determine the functional status of the battery in a short time, avoiding measurement errors caused by temperature changes.
Smart Images

Figure CN119731836A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of detecting defects in secondary batteries, and in particular, the present invention relates to an inspection device and a method for inspecting at least one secondary battery. Background Art
[0002] When manufacturing secondary batteries, i.e., battery packs that can be charged, discharged, and recharged multiple times, especially flexible secondary battery bags, contamination of secondary batteries is a common problem. This contamination may be caused, for example, by metal particles or burrs remaining on the surface of the electrodes inside the secondary battery.
[0003] In fact, in a lithium-ion battery cell, undesired contamination between two electrodes may cause a short circuit within the lithium-ion battery, leading to malfunction, damage, and in severe cases, fire of the battery.
[0004] This contamination is particularly difficult to detect in secondary batteries. Many attempts have been made to solve this problem. For example, document EP3415938 A1 describes a technique for detecting low voltage defects that may occur in secondary batteries, including the steps of assembling a secondary battery pack, aging the assembled secondary batteries, charging the aged secondary batteries, and detecting defects in the secondary batteries. If a secondary battery has a voltage drop greater than its normal self-discharge rate, a low voltage defect is considered to have occurred in the secondary battery.
[0005] However, the technique described in document EP3415938 A1 requires a considerable amount of time due to the long aging step involved. Furthermore, the technique described does not take into account the influence of temperature variations on the measured parameters.
[0006] An object of the present invention is to accurately, easily and quickly check whether contaminants are present inside a secondary battery. Summary of the invention
[0007] To this end, the present invention relates to an inspection device for inspecting at least one secondary battery, the inspection device comprising:
[0008] - fixed supporting elements;
[0009] a movable element mounted facing the support element and movable relative to the support element along the main axis in a first direction towards the support element and in a second direction opposite to the first direction, each direction being along the main axis;
[0010] - a pressing element mounted between the supporting element and the movable element, said pressing element being freely movable along a main axis, two adjacent pressing elements defining a space intended to house a secondary battery;
[0011] - a driving unit configured to operate in a first state and a second state, in which the driving unit presses at least one secondary battery between the pressing elements on both sides, and in which the driving unit releases the at least one secondary battery;
[0012] a pressure measuring unit configured to measure the pressure applied by the drive unit;
[0013] - a current control unit comprising a power supply configured to apply a voltage to at least one secondary battery and a current measurement unit for measuring a corresponding current through the at least one secondary battery;
[0014] - Each pressing element in contact with at least one secondary battery comprises a temperature sensor intended to measure the temperature of at least one secondary battery subjected to pressure between the pressing elements; the inspection device comprises a current correction unit for correcting the current measured by the current measuring unit so as to take into account the temperature value of at least one secondary battery measured by the temperature sensor.
[0015] According to one embodiment of the present invention, the inspection device further comprises a guide member configured to guide each pressing element to freely shift in the first direction and the second direction along the main axis to adjust a gap separating two adjacent pressing elements.
[0016] According to one embodiment of the present invention, the temperature sensor includes one of the following elements: a thermocouple, a resistance temperature detector, a thermistor, an integrated circuit temperature sensor.
[0017] According to an embodiment of the invention, the temperature sensor has a resolution comprised between 0.05°C and 0.5°C.
[0018] According to an embodiment of the invention, the temperature sensor has an operating temperature range comprised between 5°C and 120°C.
[0019] According to one embodiment of the present invention, the power source is capable of applying a voltage to reach a voltage value relative to the at least one secondary battery pressurized by the pressing element.
[0020] According to one embodiment, the inspection apparatus includes an electrode module connected to each electrode terminal of at least one secondary battery so as to apply or receive a current.
[0021] According to one embodiment, the current correction unit is configured to correct the current measured by the current measurement unit based on a current or voltage calibration curve.
[0022] According to one embodiment, the inspection device includes a controller, which is respectively connected to the pressure driving unit, the electrode module and the current correction unit to control the pressurization and release operations of the pressure driving unit, and determine whether there is a defect in at least one secondary battery by comparing the corrected current value given by the current correction unit and the reference current value.
[0023] According to one embodiment, the inspection device comprises a frame intended to be mounted on a support, the support element being mounted perpendicular to the frame,
[0024] The frame includes a chassis resting on a support member and a pair of support frames arranged at both sides of the chassis to face each other.
[0025] And among them:
[0026] The pressure measuring unit includes a pressure sensor inserted between a fixing member fastened to face the supporting member and a supporting frame provided on one side of the chassis,
[0027] The pressure sensor is configured to measure a pressure when the pressing element pressurizes the at least one secondary battery when the drive unit is in its first operating state.
[0028] According to one embodiment, the pressure measuring unit comprises a pressure sensor which is comprised between two adjacent ones of the pressing elements.
[0029] According to one embodiment, the space is intended to accommodate a single secondary battery.
[0030] According to one embodiment, the movable element is translationally movable in a first direction and in a second direction between a first position corresponding to the first state and a second position corresponding to the second state.
[0031] The present invention also relates to an inspection method for inspecting at least one secondary battery, the inspection method comprising the following steps:
[0032] - providing an inspection device as described above;
[0033] - providing at least one secondary battery to be inspected;
[0034] - introducing at least one secondary battery into the inspection device such that the at least one secondary battery is introduced between two adjacent pressing elements;
[0035] - pressurizing and releasing at least one secondary battery between the pressing members on both sides by displacing the movable member along the main axis in first and second directions opposite to each other along the main axis relative to the supporting member;
[0036] - measuring a pressure applied to at least one secondary battery using a pressure measurement unit in order to determine whether the applied pressure is within a predefined pressure range;
[0037] - applying a voltage to at least one secondary battery and measuring a corresponding current through the at least one secondary battery;
[0038] - measuring the temperature of at least one secondary battery with a temperature sensor included in each pressing element in contact with at least one secondary battery pressurized by the pressing unit;
[0039] - correcting the value of the measured current by taking into account a temperature value of at least one secondary battery measured by a temperature sensor;
[0040] - comparing the corrected current value with a reference current value;
[0041] - based on a comparison between the corrected current value and the reference current value, classifying at least one secondary battery as functioning properly or defective, such that:
[0042] If the correction current value exceeds the reference current value, at least one secondary battery is considered to be defective,
[0043] If the corrected current value is lower than the reference current value, it is considered that at least one secondary battery is functioning normally.
[0044] According to one embodiment, the step of providing at least one secondary battery comprises the following sub-steps:
[0045] - assembling the first electrode and the second electrode and the separator inserted between the first electrode and the second electrode to produce a bobbin or a stack;
[0046] -Putting the spool or stack into a housing or bag;
[0047] - filling the housing or bag with electrolyte;
[0048] - hermetically sealing the housing or bag so as to obtain at least one secondary battery;
[0049] - charging the at least one secondary battery to a predetermined state of charge so as to form a solid electrolyte interface on the surface of the first electrode before placing the at least one secondary battery in the inspection device. BRIEF DESCRIPTION OF THE DRAWINGS
[0050] The present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
[0051] Figure 1 1 and 2 are perspective, top and side views of an inspection device according to the present invention.
[0052] Figure 2 is based on Figure 1Cross-sectional view of the inspection device.
[0053] Figure 3 is an exploded view showing the interior of a pressing member included in the inspection device and configured to pressurize at least one secondary battery.
[0054] Figure 4 yes Figure 3 A top cross-sectional view of another embodiment of a press element comprising a cable guide incorporated into the press element.
[0055] Figure 5 is a schematic diagram of the interior of at least one secondary battery pressurized within an inspection apparatus.
[0056] In these drawings, the same reference numerals are used to refer to the same elements. For the sake of clarity, the drawings are not necessarily reproduced to scale. Additional features may appear in the following description. DETAILED DESCRIPTION
[0057] The present invention relates to an inspection device 1 for inspecting at least one secondary battery 110 , which may be, for example, a battery pouch.
[0058] Inspection device 1 Figure 1 and Figure 2 , and comprises a fixed support element 101 .
[0059] The support element 101 may be installed perpendicularly to a frame intended to be installed on a support, and the frame may include a chassis 112 resting on the support and a pair of support frames 111 provided at both sides of the chassis 112 to face each other.
[0060] The inspection device 1 further comprises a movable element 102 mounted facing the support element 101 and movable relative to the support element 101 along the main axis X in a first direction towards the support element 101 and in a second direction opposite to the first direction, each direction being along the main axis X.
[0061] The first direction is defined as a direction in which the movable element 102 approaches the supporting element 101 , and the second direction is defined as a direction in which the movable element 102 moves away from the supporting element 101 .
[0062] The inspection device further comprises a pressing element 103 mounted between the supporting element 101 and the movable element 102 and freely movable along the main axis X. Two adjacent pressing elements 102 define a space 120 intended to accommodate the secondary battery 110 .
[0063] The space 120 is intended to accommodate a single secondary battery 110. By accommodating only a single secondary battery, the battery 110 can be accurately measured.
[0064] The pressing element 103 may in particular be a pressure panel, which may be mounted in parallel between the supporting element 101 and the movable element 102 .
[0065] The inspection device 1 further comprises:
[0066] a guide element 104 configured to guide each pressing element 103 to be freely displaced in a first direction and a second direction along the main axis X so as to adjust the space 120 separating two adjacent pressing elements 103 ;
[0067] as well as
[0068] a driving unit 105 configured to operate in a first state in which the driving unit 105 presses at least one secondary battery 110 between the pressing elements 103 on both sides and in a second state in which the driving unit 105 releases the at least one secondary battery 110,
[0069] The operational change between the first state and the second state is achieved by displacing the movable element 102 in the first direction and the second direction;
[0070] A pressure measuring unit configured to measure the pressure exerted by the drive unit 105 .
[0071] Advantageously, the guide element 104 makes it possible to obtain substantially parallel plates, thereby making it possible to obtain useful pressure measurements.
[0072] According to one embodiment, the pressure measuring unit includes a pressure sensor 106, which is inserted between a fixing element fastened to face the supporting element 101 and a supporting frame arranged on one side of the chassis 112, and the pressure sensor 106 can be configured to measure the pressure when the pressing element 103 pressurizes at least one secondary battery 110 when the driving unit 105 is in its first operating state.
[0073] According to one embodiment, the pressure measuring unit includes a pressure sensor included between two adjacent pressing elements in the pressing elements 103, and the pressure sensor 106 may be a load cell, a strain gauge, a force sensitive resistor, or a combination of all cited pressure sensors.
[0074] The inspection device 1 may also include an elastic support unit, which is configured to elastically support the support element 101 so that it returns to the pressing element side, wherein the elastic support unit may include a fixing element fastened to face the support element 101 and a compression spring 107, which is inserted into the guide member 104 to be positioned between the fixing element and the support element 101.
[0075] The inspection device is notable in that each pressing element 103 in contact with at least one secondary battery 110 includes a temperature sensor 109, such as Figure 3 and Figure 4 The temperature sensor 109 is intended to measure the temperature of at least one secondary battery 110 that is pressed between the pressing elements 103 .
[0076] According to one embodiment, the temperature sensor 109 comprises one of the following elements: a thermocouple, a resistance temperature detector, a thermistor, an integrated circuit temperature sensor, and the temperature sensor 109 has a resolution comprised between 0.05°C and 0.5°C.
[0077] according to Figure 4 In the embodiment shown, the cable guide 130 is connected to the temperature sensor 109, and both the cable guide 130 and the temperature sensor 109 are embedded in the pressing element 103. This advantageously makes it possible to measure temperature values while avoiding excessive thickness.
[0078] This resolution range makes it possible to accurately detect the temperature of at least one secondary battery 110 .
[0079] The temperature sensor 109 may have an operating temperature range comprised between 5°C and 120°C.
[0080] Advantageously, this operating temperature range is adapted to the operating conditions of the inspection device 1 .
[0081] The inspection device 1 further includes a current control unit configured to apply a voltage to the at least one secondary battery 110 and measure a corresponding current passing through the at least one secondary battery 110 .
[0082] The current control unit may include:
[0083] a power source for applying a voltage to reach a predetermined voltage value relative to the at least one secondary battery 110 pressed by the pressing element 103; and
[0084] A current measuring unit for measuring a value of a current flowing through at least one secondary battery 110 .
[0085] Advantageously, the current control unit performs control of the current of the at least one stressed secondary battery 110 , which makes it possible to measure the current flowing through the at least one secondary battery 110 .
[0086] The current control unit applies a predetermined voltage to the at least one secondary battery 110 and measures a current of the at least one secondary battery 110 .
[0087] The inspection apparatus 1 may further include an electrode module connected to each electrode terminal of the at least one secondary battery 110 so as to apply or receive current.
[0088] The inspection device 1 may further include a current correction unit for correcting the current measured by the current measurement unit so as to take into account the temperature value of the at least one secondary battery 110 measured by the temperature sensor 109 .
[0089] The current correction unit is configured to correct the current measured by the current measurement unit based on a current or voltage calibration curve.
[0090] The calibration curve may be an abacus which gives predefined current or voltage values of the at least one secondary battery 110 as a function of the temperature of the at least one secondary battery 110. These predefined current and voltage values may be determined experimentally.
[0091] These values may change based on feedback and data collection after producing and inspecting multiple secondary batteries.
[0092] The term "correction of the measured current" means that the current value measured by the current control unit is erroneous due to the temperature dependency of the measured current and this value is analyzed by the current correction unit taking into account the temperature dependency of the measured current in order to give a corrected current value taking into account the temperature dependency of the current. This corrected current value is compared with a reference current value.
[0093] According to another embodiment, the measured current value is compared with a corrected reference current value, which means that the reference current value will be different for each temperature value.
[0094] The inspection device 1 also includes a controller, which is respectively connected to the pressure driving unit, the electrode module and the current correction unit, for controlling the pressurization and release operations of the pressure driving unit, and for determining whether there is a defect in at least one secondary battery 110 by comparing the corrected current value given by the current correction unit and the reference current value.
[0095] The controller may determine whether there is a defect by comparing an average value of the current value measured by the current control unit with a reference value during a predetermined time period, which may depend on a user control parameter of the inspection device.
[0096] The predetermined time period may be 1 to 30 seconds.
[0097] The reference current value may be determined experimentally, for example, by referring to a calibration curve or an abacus that indicates whether the at least one secondary battery 110 is defective according to the measured current value.
[0098] The inspection apparatus 1 can allow many secondary batteries 110 to be inspected simultaneously.
[0099] The inspection device 1 is intended to pressurize at least one secondary battery 110 to allow or improve physical contact between the first electrode 201 and the second electrode 202 across the contaminant 2 , thereby inducing a current flowing through the contaminant 2 between the first electrode 201 and the second electrode 201 .
[0100] like Figure 5 As shown, the pressure applied to the at least one secondary battery 110 improves the detection of potential contaminants 2 inside the at least one secondary battery 110; therefore, the current flowing through the contaminants 2 is easier to detect.
[0101] The first electrode 201 may be a cathode and the second electrode 202 may be an anode, or vice versa.
[0102] The operation of the inspection device 1 will now be described.
[0103] When at least one secondary battery 110 is introduced into the inspection device 1 , the movable member 102 installed to face the supporting member 101 is displaced in the first and second directions along the main axis X by the driving unit 105 to pressurize and decompress the pressing member 103 .
[0104] The movable element 102 is displaced in a first direction along the main axis X so as to pressurize at least one secondary battery 110. A predetermined potential is applied to the battery, and then the current in the at least one secondary battery 110 is measured, and then after the current is measured, the movable element 102 is displaced in a second direction along the main axis X so as to release the at least one secondary battery 110.
[0105] The movable element 102 is movable along the first direction and the second direction between a first position and a second position. The first position corresponds to a first state where the battery is pressed by the driving unit 105, and the second position corresponds to a second state where the battery is released by the driving unit 104.
[0106] The pressing member 103 pressurizes the main body portion of the at least one secondary battery 110. Here, the main body portion refers to the main body portion of the at least one secondary battery 110 except for electrode terminals protruding from the at least one secondary battery 110.
[0107] When the pressing member 103 pressurizes the at least one secondary battery 110 , a pressure measuring unit may be disposed between the fixing member and the supporting frame to measure the pressure.
[0108] If the pressure applied to at least one secondary battery 110 is too high, the electrodes may be detached, or the appearance of at least one secondary battery 110 may be damaged. On the contrary, if the pressure is too low, the first electrode 201 and the second electrode 202 may not be in physical contact with each other through the contaminant 2, so that the internal short circuit may not be triggered, which reduces the reliability of fault detection. Therefore, by detecting the pressure applied to at least one secondary battery 110 via the pressure sensor 106, it is possible to check whether an appropriate level of pressure is applied.
[0109] Then, a voltage is applied by the current control unit to perform current control on the at least one pressurized secondary battery 110. To this end, a power source included in the current control unit applies a voltage across the electrode module to reach a predetermined voltage value, and a current measuring unit measures a current value flowing through the at least one secondary battery 110.
[0110] The current control unit and the electrode module may be electrically connected via a cable or any other electrical connection means.
[0111] The electrode module electrically connects the current control unit to the at least one secondary battery 110. The electrode module may be attached to the inspection device 1. The electrode module is connected to each electrode terminal of the at least one secondary battery 110, and applies a current applied by the current control unit to the at least one secondary battery 110, or transmits a current from the at least one secondary battery 110 to the current control unit.
[0112] Since the measured current is sensitive to temperature changes, the temperature of at least one secondary battery 110 is measured using a temperature sensor 109 included in each pressing element 103 in contact with at least one secondary battery 110. With the help of the current correction unit, a corrected measured current value can be obtained while taking into account the temperature dependency of the current. This makes it possible to compare the corrected current value with the reference current value while taking into account the battery temperature and helps to avoid classification errors.
[0113] Then, the controller connected to the drive unit 105, the electrode module, and the current correction unit compares the correction current value obtained by the current correction unit with the reference current value to determine whether there is a fault. In addition, the controller can compare the correction current value of at least one secondary battery 110 measured by the current control unit with a predetermined reference value of a good product, and determine whether the value is acceptable according to a predetermined standard. The result of the determination can be displayed by a display unit not shown.
[0114] Therefore, the controller determines whether at least one secondary battery 110 is good according to whether the measured value of the measured power or insulation corresponds to a predetermined standard, and can enable the display unit or data output device to display the determination result of at least one secondary battery 110.
[0115] The present invention also relates to an inspection method for inspecting at least one secondary battery 110 .
[0116] The inspection method includes the steps of providing the inspection device 1 as described above and providing at least one secondary battery 110 to be inspected.
[0117] In order to provide at least one secondary battery 110 to be inspected, the following sub-steps may be performed:
[0118] - assembling at least a first electrode 201 and a second electrode 202 and a separator 203 interposed between the first electrode 201 and the second electrode so as to produce a bobbin or a stack;
[0119] - placing the spool or stack in a housing or bag;
[0120] - filling the housing or bag with electrolyte;
[0121] - hermetically sealing the housing or bag so as to obtain at least one secondary battery 110;
[0122] - charging the at least one secondary battery 110 to a predetermined state of charge so as to form a solid electrolyte interface on the surface of the first electrode 201 before placing the at least one secondary battery 110 in the inspection device.
[0123] According to one possibility, a bobbin or stack may be created by assembling a number of first electrodes, a number of second electrodes, a number of separators and other additional layers.
[0124] Then, once the inspection device 1 and at least one secondary battery 110 to be inspected are provided, the following steps are performed:
[0125] - introducing at least one secondary battery 110 into the inspection device 1 such that the at least one secondary battery 110 is introduced between two adjacent pressing elements 103;
[0126] - pressing and releasing at least one secondary battery 110 between the pressing elements 103 on both sides by displacing the movable element 102 relative to the supporting element 101 along the main axis X in first and second directions opposite to each other along the main axis X;
[0127] - Using a pressure measuring unit to measure the pressure applied to at least one secondary battery 110, so as to determine whether the applied pressure is within a predefined pressure range, which may be comprised between 200 and 5000 kgf / cm 2 between;
[0128] - applying a voltage to at least one secondary battery 110 and measuring a corresponding current through at least one secondary battery 110;
[0129] - measuring the temperature of at least one secondary battery 110 with a temperature sensor 109 included in each pressing element 103 in contact with at least one secondary battery 110 subjected to the pressure of the pressing element 103;
[0130] The value of the measured current is corrected by taking into account the temperature value of at least one secondary battery 110 measured by the temperature sensor 109 .
[0131] Then, in order to classify at least one secondary battery 110 as being functionally normal or defective, the following steps may be performed:
[0132] - comparing the corrected current value with a reference current value;
[0133] - based on the comparison between the corrected current value and the reference current value, classifying at least one secondary battery 110 as functioning properly or defective, such that:
[0134] - if the corrected current value exceeds the reference current value, at least one secondary battery 110 is considered to be defective,
[0135] If the corrected current value is lower than the reference current value, it is considered that at least one secondary battery 110 is functioning properly.
[0136] The pressure sensor 106 makes it possible to check whether the applied pressure value is appropriate.
[0137] Advantageously, the checking method makes it possible to take into account the temperature dependency of the current measured by at least one secondary battery 110 and to correct the measured current before comparing it with a reference value.
[0138] The measured current flowing through the secondary battery depends on the temperature and will therefore be measured more accurately using the inspection method.
[0139] The inspection method allows for more accurate classification of at least one inspected secondary battery 110 .
[0140] Advantageously, the inspection method may be applied during the manufacturing process of the at least one secondary battery 110 , after the electrolyte impregnation phase and before the first charging of the at least one secondary battery 110 .
[0141] Advantageously, the inspection method can be applied after the cell is formed.
[0142] The above inspection method and device have industrial applications in the field of manufacturing secondary batteries.
[0143] Contents in this detailed description that apply to the inspection method also apply to the inspection device, and vice versa.
[0144] Although the invention has been described with respect to specific embodiments, it is obviously not restricted thereto and comprises all technical equivalents of the means and combinations thereof, as long as these fall within the scope of the invention.
Claims
1. An inspection device (1) for inspecting at least one secondary battery (110), the inspection device comprising: - a fixed supporting element (101); - a movable element (102) mounted facing the support element (101) and movable relative to the support element (101) along a main axis (X) in a first direction towards the support element (101) and in a second direction opposite to the first direction, each direction being along the main axis (X); - a pressing element (103) mounted between said supporting element (101) and said movable element (102), said pressing element (103) being freely movable along said main axis (X), Two adjacent pressing elements (103) define a space (120) intended to accommodate a secondary battery (110); - a driving unit (105) configured to operate in a first state and a second state, in which the driving unit (105) presses at least one secondary battery (110) between the pressing elements (103) on both sides, and in which the driving unit (105) releases the at least one secondary battery (110); - a pressure measuring unit configured to measure the pressure applied by the drive unit (105); a current control unit comprising a power source configured to apply a voltage across the at least one secondary battery (110) and a current measuring unit for measuring a corresponding current through the at least one secondary battery (110), - each pressing element (103) in contact with said at least one secondary battery (110) comprises a temperature sensor (109) intended to measure the temperature of at least one secondary battery (110) pressed between said pressing elements (103), The inspection device (1) includes a current correction unit for correcting the current measured by the current measurement unit so as to take into account a temperature value of at least one secondary battery (110) measured by the temperature sensor (109).
2. The inspection device (1) according to claim 1 further includes a guiding element (104), which is configured to guide each pressing element (103) to freely shift in the first direction and the second direction along the main axis (X) so as to adjust the space (120) separating two adjacent pressing elements (103).
3. The inspection device (1) according to any one of claims 1 or 2, wherein: The temperature sensor (109) comprises one of the following elements: a thermocouple, a resistance temperature detector, a thermistor, an integrated circuit temperature sensor.
4. The inspection device (1) according to any one of claims 1 to 3, wherein: The temperature sensor (109) has a resolution comprised between 0.05°C and 0.5°C.
5. The inspection device (1) according to any one of claims 1 to 4, wherein: The temperature sensor (109) has an operating temperature range comprised between 5°C and 120°C.
6. The inspection device (1) according to any one of claims 1 to 5, wherein: The power source is adapted to apply a voltage to achieve a voltage value relative to the at least one secondary battery pressurized by the pressing element.
7. The inspection device (1) according to any one of claims 1 to 6, further comprising an electrode module connected to each electrode terminal of the at least one secondary battery (110) so as to apply or receive current.
8. The inspection device (1) according to any one of claims 1 to 7, wherein the current correction unit is configured to correct the current measured by the current measurement unit based on a current or voltage calibration curve.
9. The inspection device (1) according to any one of claims 1 to 8, further comprising a controller, which is respectively connected to the pressure drive unit, the electrode module and the current correction unit, for controlling the pressurization and release operations of the pressure drive unit, and for determining whether there is a defect in the at least one secondary battery (110) by comparing the corrected current value given by the current correction unit with a reference current value.
10. The inspection device according to any one of claims 1 to 9, comprising a frame intended to be mounted on a support, the support element (101) being mounted perpendicular to the frame, the frame comprising a chassis (112) resting on the support and a pair of support frames (111) provided on both sides of the chassis (112) to face each other, and wherein: The pressure measuring unit includes a pressure sensor (106) inserted between a fixing element fastened to face the supporting element (101) and a supporting frame provided on one side of the chassis (112), The pressure sensor (106) is configured to measure the pressure when the pressing element (103) pressurizes the at least one secondary battery (110) when the drive unit (105) is in its first operating state.
11. The inspection device (1) according to any one of claims 1 to 10, wherein: The pressure measuring unit includes a pressure sensor included between two adjacent pressing elements (103) among the pressing elements.
12. The inspection device (1) according to any one of claims 1 to 11, wherein: The space (120) is intended to accommodate a single secondary battery (110).
13. The inspection device (1) according to any one of claims 1 to 12, wherein: The movable element (102) is translationally movable in the first direction and the second direction between a first position corresponding to the first state and a second position corresponding to the second state.
14. An inspection method for inspecting at least one secondary battery, the inspection method comprising the following steps: - providing an inspection device (1) according to any one of claims 1 to 13; - providing at least one secondary battery (110) to be inspected; - introducing the at least one secondary battery (110) into the inspection device (1) such that the at least one secondary battery (110) is introduced between two adjacent pressing elements (103); - pressurizing and releasing at least one secondary battery (110) between the pressing elements (103) on both sides by displacing the movable element (102) relative to the supporting element (101) along the main axis (X) in a first direction and a second direction opposite to each other along the main axis (X); - measuring the pressure applied to the at least one secondary battery (110) using the pressure measuring unit to determine whether the applied pressure is within a predefined pressure range; - applying a voltage to the at least one secondary battery (110) and measuring a corresponding current through the at least one secondary battery (110); - measuring the temperature of the at least one secondary battery (110) with a temperature sensor (109) included in each pressing element (103) in contact with the at least one secondary battery (110) pressed by the pressing element (103); - correcting the value of the measured current by taking into account the temperature value of at least one secondary battery (110) measured by said temperature sensor (109); - comparing the corrected current value with a reference current value; - based on a comparison between the corrected current value and the reference current value, classifying the at least one secondary battery (110) as functioning properly or defective, such that: If the correction current value exceeds the reference current value, the at least one secondary battery (110) is considered to be defective, If the corrected current value is lower than the reference current value, it is considered that the at least one secondary battery (110) functions normally.
15. The inspection method according to claim 14, wherein: The step consisting of providing the at least one secondary battery comprises the following sub-steps: - assembling a first electrode (201) and a second electrode (202) and a separator (203) interposed between the first electrode (201) and the second electrode (202) to produce a bobbin or a stack; - placing the bobbin or the stack in a housing or bag; - filling the housing or bag with electrolyte; - hermetically sealing the housing or bag so as to obtain the at least one secondary battery (110); - charging the at least one secondary battery (110) to a predetermined state of charge so as to form a solid electrolyte interface on the surface of the first electrode (201) before placing the at least one secondary battery (110) in the inspection device.
Citation Information
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