Leak testing system

Abstract

A leak testing system includes a first test station, a second test station, a conveyor, and a controller. The first test station includes a first infrared camera with a first CO2 optical lens filter, a first background with a first heated surface and a first mirror, a first vacuum source, and a first CO2 gas delivery system. The second test station includes a second infrared camera with a second CO2 optical lens filter, a second background with a second heated surface and a second mirror, a second vacuum source, and a second CO2 gas delivery system. The first infrared camera is arranged to monitor a first field of view including the first background. The second infrared camera is arranged to monitor a second field of view including the second background. The controller includes a cell testing method encoded in algorithmic code.

Description

introduction

[0001] A rechargeable energy storage system (RESS) can be deployed in a stationary energy storage system or in a mobile device, such as an electric vehicle (EV). As part of an electric vehicle, an electric powertrain uses one or more electric machines to generate torque using energy derived at least in part from a RESS, with the generated torque being delivered to a driveline for tractive power.

[0002] A RESS may include a battery cell pack comprised of a plurality of prismatic, pouch-shaped electrochemical battery cells. The battery cells, in one embodiment, may be lithium-ion battery cells, but the disclosure is not so limited. The battery cells may include lithium-class batteries, nickel-metal hydride batteries, ultracapacitor batteries, and lead-acid batteries. As with lithium batteries, lithium metal and lithium-ion (Li-ion) batteries constitute the majority of commercial lithium battery (LiB) configurations, with Li-ion batteries being used in automotive applications due to their improved stability, energy density, and rechargeability. A lithium-ion cell may include at least two conductive electrodes, an electrolyte material, and a permeable separator, all enclosed in an electrically insulated package containing an electrolyte.

[0003] DE 10 2020 102 463 A1 describes a method for testing a leak and a device therefor. The method comprises introducing a first gas into a power supply, wherein the first gas differs from a second gas in the vicinity of the power supply, detecting a gas in the vicinity of the power supply, and analyzing the detected gas to determine whether it contains traces of the first gas.

[0004] DE 10 2023 123 005 A1 describes a method for testing a battery component for leakage. The method comprises generating a sample from a battery component storing electrolyte using a Fourier transform infrared spectrometer (FT-IR), comparing absorption levels of the sample at N predetermined frequencies with N predetermined thresholds, where N is an integer greater than one, and selectively detecting at least one electrolyte leak and generating an electrolyte concentration estimate in response to the comparison. The battery component is selected from a group consisting of a battery cell, a battery module, and a battery pack. Description of the invention

[0005] During the manufacturing of rechargeable battery cells, particularly prismatic lithium metal cells, a metered volume of compressed gas, such as carbon dioxide (CO2), may be introduced into the cell's rigid battery casing to pressurize the cell for leak testing. To ensure continuous and uninterrupted operation of the battery system, each cell is tested during the manufacturing process to ensure that no leaks are present.

[0006] The concepts described herein provide elements relating to a method, system, and / or apparatus for non-destructive leak testing of a prismatic battery cell, including a manner that may include identifying a leak location to enable repair and verification of the manufacturing process.

[0007] One aspect of the disclosure may include a leak testing system including a first testing station, a second testing station, a conveyor, and a controller. The first testing station is connected to the second testing station via the conveyor. The first testing station includes a first infrared camera equipped with a first CO2 optical lens filter, a first backdrop with a first heated surface and a first mirror, a first vacuum source, and a first CO2 gas supply system. The second testing station includes a second infrared camera with a second CO2 optical lens filter, a second backdrop with a second heated surface and a second mirror, a second vacuum source, and a second CO2 gas supply system. The first infrared camera is arranged to monitor a first field of view including the first background image.when the first background image is in a first test position. The second infrared camera is arranged to monitor a second field of view that includes the second backdrop when the second backdrop is in a second test position. The controller is in communication with the first test station, the second test station, and the conveyor. The controller includes a cell testing method captured in algorithmic code stored in non-volatile memory. The cell testing method includes the following steps: placing an unfilled prismatic battery cell (cell) at the first test station; placing the first backdrop in the first test position,wherein the first test position is located near a first portion of the cell; pressurizing the cell using CO2 gas at the first test station; monitoring an outer portion of the first portion of the cell and the background via the first infrared camera to detect the presence of CO2 gas; transporting the cell via the conveyor to the second test station; placing the second background in the second test position, the second test position being close to a second portion of the cell; pressurizing the cell using CO2 gas at the second test station; monitoring an outer portion of the second portion of the cell and the backdrop via the second infrared camera to detect the presence of CO2 gas; detecting a leak in the cell via the controller,when the first infrared camera detects the presence of CO2 gas near the outer portion of the first section of the cell; and detecting a leak in the cell via the controller when the second infrared camera detects the presence of CO2 gas near the outer portion of the second section of the cell.

[0008] Another aspect of the disclosure may include the first background being a C-channel having a land portion and first and second side portions, wherein the land portion and the first and second side portions are arranged to enclose the first portion of the cell when the first background is arranged in the first test position.

[0009] Another aspect of the disclosure may include the second background being a C-channel having a web portion and first and second side portions, wherein the web portion and the first and second side portions are arranged to enclose the second portion of the cell when the second background is arranged in the first test position.

[0010] Another aspect of the disclosure may include the first background being a first C-channel section made of aluminum, the first background having a surface treatment capable of absorbing infrared light.

[0011] Another aspect of the disclosure may include the second background being a second C-channel section made of aluminum, the second background having a surface treatment capable of absorbing infrared light.

[0012] Another aspect of the disclosure may include a first environmental enclosure and a second environmental enclosure, wherein the first test station is disposed in the first environmental enclosure and wherein the second test station is disposed in the second environmental enclosure.

[0013] Another aspect of the disclosure may include that the cell testing method further comprises a step of identifying a leak location on the cell via the controller when the first infrared camera detects the presence of CO2 gas near the outer part of the first part of the cell.

[0014] Another aspect of the disclosure may include that the cell testing method further comprises a step of identifying a leak location on the cell via the controller when the second infrared camera detects the presence of CO2 gas near the outer part of the second part of the cell.

[0015] Another aspect of the disclosure may include the first background being attached to a first frame portion of the first test station via a first extension piece, wherein the first extension piece can be controlled to either a retracted or an extended state. The method for testing the cell further comprises the steps of controlling the first extension piece to the extended state before arranging the first backdrop and the first mirror in the first test position, and controlling the first extension piece to the retracted state before transporting the cell to the second test station via the conveyor.

[0016] Another aspect of the disclosure may include the second backdrop being attached to a second frame portion of the second test station via a second extension piece. The second extension piece can be controlled to either a retracted or an extended state. The cell testing method further includes a step of controlling the second extractor to the extended state prior to the step of arranging the second background and the second mirror in the second test position.

[0017] Another aspect of the disclosure may include the cell testing method further comprising the steps of pressurizing the cell to a predetermined pressure level using CO2 gas at the first test station; and monitoring the exterior of the first portion of the cell via the first infrared camera to detect the presence of CO2 gas when the pressure in the cell at the first test station reaches the predetermined pressure level.

[0018] Another aspect of the disclosure may include that the method for testing the cell further comprises the steps of pressurizing the cell to a predetermined pressure level using CO2 gas at the second test station; and monitoring the exterior portion of the second portion of the cell via the second infrared camera to detect the presence of CO2 gas when the pressure in the cell at the second test station reaches the predetermined pressure level.

[0019] Another aspect of the disclosure may include a leak testing system comprising a first testing station disposed in a first environmental enclosure, a second testing station disposed in a second environmental enclosure, a conveyor, and a controller; wherein the first testing station is connected to the second testing station via the conveyor; wherein the first testing station comprises a first camera, a first backdrop, a first mirror, and a first gas delivery system; wherein the second testing station has a second camera, a second background image, a second mirror, and a second gas delivery system; wherein the first camera is arranged to monitor a first field of view including the first background image when the first background image is in a first testing position;wherein the second camera is arranged to monitor a second field of view including the second background image when the second background image is in a second test position; and wherein the controller is in communication with the first test station, the second test station, and the conveyor. The controller includes a cell testing procedure captured in algorithmic code stored in non-volatile memory, the cell testing method comprising the steps of: exposing the cell to gas via the first gas supply system at the first test station; monitoring an external portion of a first portion of the cell via the first camera to detect the presence of the gas; transporting the cell via the conveyor to the second test station; exposing the cell to gas via the second gas supply system at the second test station;Monitoring an outer region of a second region of the cell via the second camera to detect the presence of the gas; detecting a leak in the cell via the controller when the first camera detects the presence of the gas near the outer region of the first region of the cell; and detecting a leak in the cell via the controller when the second camera detects the presence of the gas near the outer region of the second region of the cell.

[0020] Another aspect of the disclosure may include a method for leak testing, the method comprising placing an unfilled prismatic battery cell (cell) at a first test station; placing a first background and a first mirror in a first test position, the first test position being proximate a first portion of the cell; pressurizing the cell using CO2 gas; monitoring an outer portion of the first portion of the cell using a first infrared camera to detect the presence of CO2 gas; transporting the cell to a second test station; placing a second background and a second mirror in a second test position, the second test position being proximate a second portion of the cell; pressurizing the cell using CO2 gas;Monitoring an exterior of the second region of the cell via a second infrared camera to detect the presence of CO2 gas; detecting a leak in the cell via a controller in communication with the first infrared camera when the first infrared camera detects the presence of CO2 gas near the exterior of the first region of the cell; and detecting a leak in the cell via the controller in communication with the second infrared camera when the second infrared camera detects the presence of CO2 gas near the exterior of the second region of the cell.

[0021] Another aspect of the disclosure may include identifying, via the controller, a location of the leak on the cell when the first infrared camera detects the presence of CO2 gas near the outer portion of the first portion of the cell; and identifying, via the controller, the location of the leak on the cell when the second infrared camera detects the presence of CO2 gas near the outer portion of the second portion of the cell.

[0022] Another aspect of the disclosure may include pressurizing the cell using CO2 gas to a predetermined pressure level at the first test station; monitoring, via the first infrared camera, the exterior of the first portion of the cell to detect the presence of CO2 gas when the pressure in the cell reaches the predetermined pressure level at the first test station; pressurizing the cell with CO2 gas to a predetermined pressure level at the second test station; and monitoring, via the second infrared camera, the exterior of the second portion of the cell to detect the presence of CO2 gas when the pressure in the cell is at the predetermined pressure level at the second test station.

[0023] The above features and advantages, as well as other features and advantages of the present teachings, are readily apparent from the following detailed description of some of the best modes and other embodiments for carrying out the present teachings as defined in the appended claims, when considered in conjunction with the accompanying drawings. Brief description of the drawings

[0024] One or more embodiments will now be described by way of example with reference to the accompanying drawings, in which: Fig. 1 schematically shows an isometric view of a leak testing system according to the disclosure. Fig. 2 schematically shows a side view of a leak testing system according to the disclosure. Fig. 3 schematically shows an isometric view of a portion of a leak testing system according to the disclosure. Fig.4A schematically shows a side view of a leak testing system with a retracted gate according to the disclosure. Fig. 4B schematically shows a side view of a leak testing system with an extended gate according to the disclosure. Fig. 5 shows a flowchart of a routine for detecting leaks in accordance with the disclosure.

[0025] The accompanying drawings are not necessarily to scale and present a somewhat simplified representation of various features of the present disclosure as disclosed herein, including, for example, specific dimensions, orientations, positions, and shapes. Details associated with such features will be determined in part by the particular intended application and environment of use. Detailed description

[0026] The components of the embodiments described and illustrated herein can be arranged and implemented in a variety of different configurations. Therefore, the following detailed description is not intended to limit the scope of the disclosure as claimed, but is merely representative of possible embodiments thereof. Moreover, while numerous specific details are set forth in the following description in order to provide a thorough understanding of the embodiments disclosed herein, some embodiments may be practiced without some of these details. Moreover, for the sake of clarity, certain technical material known in the related art has not been described in detail so as not to unnecessarily obscure the disclosure.

[0027] For simplicity and clarity, directional terms such as top, bottom, left, right, upper, top, top, bottom, bottom, rear, and front may be used in the drawings. These and similar directional terms are not to be construed as limiting the scope of the disclosure. Furthermore, the disclosure as shown and described herein may be practiced without any element not expressly disclosed herein.

[0028] The following detailed description provides details of the concepts described and claimed and is not intended to limit the application and uses. Furthermore, there is no intention to be bound by any expressed or implied theory contained herein. In the drawings, corresponding reference numerals indicate like or corresponding parts and features.

[0029] As used herein, the term “system” may refer to one or a combination of mechanical and electrical actuators, sensors, controllers, application-specific integrated circuits (ASICs), combinational logic circuits, software, firmware, and / or other components arranged to provide the described functionality.

[0030] The embodiments may be described herein in terms of functional and / or logical block components and various processing steps. Such block components may be implemented by a combination or collection of mechanical and electrical hardware, software, and / or firmware components configured to perform the specified functions. For example, an embodiment may employ various combinations of mechanical and electrical components, integrated circuit components, memory elements, digital signal processing elements, logic elements, lookup tables, or the like, capable of performing a variety of functions under the control of one or more microprocessors or other devices.Furthermore, those skilled in the art will recognize that the illustrated embodiments may be used in conjunction with mechanical and / or electronic systems and that the vehicle systems described herein are merely illustrative embodiments of possible implementations.

[0031] For brevity, conventional components and techniques, as well as other functional aspects of the systems (and the individual operating components of the systems), are not described in detail here. Furthermore, the connecting lines depicted in the various figures are intended to represent exemplary functional relationships and / or physical connections between the various elements. Many alternative or additional functional relationships or physical connections may be present in an embodiment of the disclosure.

[0032] Furthermore, the first definition of an acronym or other abbreviation shall apply to subsequent uses of the same abbreviation and, mutatis mutandis, to normal grammatical variations of the originally defined abbreviation; and unless explicitly stated otherwise, the measurement of a property shall be determined by the same technique previously or subsequently referred to for the same property.

[0033] It is also to be understood that this disclosure is not limited to the embodiments and methods described below, as specific components and / or conditions may, of course, vary. Furthermore, the terminology used herein is for the purpose of describing particular embodiments of the present disclosure and is not intended to be limiting.

[0034] As used in the description and the appended claims, the singular forms "a," "an," and "the" refer to plurals unless the context clearly indicates otherwise. For example, when referring to a component in the singular, this is intended to refer to a plurality of components.

[0035] The use of ordering terms such as “first,” “second,” and “third” does not necessarily imply a ranking, but rather can distinguish between multiple instances of an action or structure.

[0036] Numerical values ​​of parameters (e.g., of quantities or conditions) in this specification, including the appended claims, are to be understood as being modified by the term "approximately," whether or not "approximately" actually appears before the numerical value. "Approximately" means that the stated numerical value allows for slight imprecision (within some approximation of the accuracy of the value; approximately or reasonably close to the value; almost). Unless the imprecision provided by "approximately" is otherwise understood in the art, "approximate," as used herein, means at least variations that might arise from ordinary methods of measuring and using such parameters. Each value within a range, and the endpoints of a range, are hereby disclosed as separate embodiments.

[0037] As used herein, terms such as "vertical," "horizontal," "left," "right," "top," "bottom," and similar expressions are non-limiting terms that merely describe the various elements as illustrated in the figures and are not intended to limit the scope of the disclosure.

[0038] Referring now to the drawings, which are for illustrating certain exemplary embodiments and not for limiting the same, Fig. 1, Fig. 2, Fig. 3, Fig. 4A and Fig.4B schematically illustrates various elements associated with a leak detection system 10 that can advantageously be manufactured and used to perform a leak detection routine 140 on an embodiment of a prismatic battery cell 200, including performing the leak detection routine 140 on an embodiment of the prismatic battery cell 200 prior to filling a liquid electrolyte into a sealable bag thereof. Details of the leak detection routine 140 are described with reference to Fig. 5 described.

[0039] As can be seen from the Fig. 1, Fig. 2, Fig. 3, Fig. 4A and Fig.4B, the leak testing system 10 includes a first test station 20, a second test station 60, a conveyor 100, and a controller 120. The first test station 20 is connected to the second test station 60 via the conveyor 100 to effect movement of the prismatic battery cell 200 from the first test station 20 to the second test station 60.

[0040] The prismatic battery cell 200 has an outer portion including a first, nominally front side 201, a second, nominally rear side 202, a first end 203, a second end 204, a top side 205, and a bottom side (not shown) that are visible to the leak testing system 10 in the first test station 20 and / or the second test station 60, or both.

[0041] The first and second inspection stations 20, 60 each use a machine vision system in the form of an optical gas imaging (OGI) system to detect the occurrence and location of a gas leak in one embodiment of the prismatic battery cell 200 by monitoring the outer part of the prismatic battery cell 200, i.e., the first, nominally front side 201, the second, nominally rear side 202, the first end 203, the second end 204, the top 205, and the bottom. In one embodiment, the image processing elements comprise a digital camera with a gas-specific lens filter and a non-reflective background, which is deployed in an environmental chamber, with the signal processing of the images captured by the digital camera taking place in the controller 120.The first and second inspection stations 20, 60 are each configured and arranged to fill the prismatic battery cell 200 with a pressurized gaseous substance and employ the image processing elements to detect the occurrence and location of a gas leak on at least a portion of an exterior surface of the prismatic battery cell 200 under static ambient airflow and thermal conditions.

[0042] The first test station 20 consists of a first frame part 22 with a base part 23, opposing legs 24, 25, a first mounting post 26, a second mounting post 27, and a first environmental chamber 28. The first environmental chamber 28 is configured as a rectangular prism with transparent sides and top parts and an open bottom part. The first environmental chamber 28 is mounted on the first frame part 22 and serves to create a static ambient airflow and thermal conditions around the prismatic battery cell 200 during testing.

[0043] The OGI system of the first inspection station 20 includes a first infrared camera 30 equipped with a first optical lens filter 32, a first gate 35, a first mirror 50, a first vacuum source 52, and a first gas supply system 54. In one embodiment, the first gas supply system 54 is a CO2 gas supply system, and the first optical lens filter 32 is in the form of a CO2 optical lens filter. Alternatively, another gaseous substance may be used, with leak detection being performed by a corresponding imaging system.

[0044] The first infrared camera 30 is equipped with a first optical lens filter 32 and is connected to the controller 120. The first infrared camera 30 is mounted on the first mounting column 26 such that it has a first field of view (FOV) 34 that encompasses the prismatic battery cell 200 during inspection. Location and mounting positions, working distances, angles, FOVs, and other parameters are application-specific and can be determined by experienced practitioners.

[0045] The first gate 35 is arranged as a first open channel 38, e.g., a C-channel, which is attached via a first controllable extension piece 45 to the second mounting post 27, to which a first heating element 36 is attached. In one embodiment, the first open-edged channel 38 is made of aluminum with a web portion 40 and side portions 42. The surface 44 of the first open channel 38 is treated to minimize or eliminate light reflection, particularly the reflection of infrared light. In one embodiment, the surface 44 of the first open-edged channel 38 is black anodized to minimize the reflection of infrared light. The first mirror 50 is arranged on the first gate 35 in a corner between the web portion 40 and one of the side portions 42.The first heating element 36 is a silicon or positive temperature coefficient heater operatively connected to the controller 120 and controllable to maintain a stable thermal environment within the first environmental chamber 28 during testing. The first controllable deployment device 45 is configured to move the first backrest 35 to either a retracted position 48 (. Fig. 4A) or an extended position 46 ( Fig.4B). In one embodiment, the first controllable extension device 45 is designed as a pneumatic cylinder. The first guide 35 is advantageously positioned in the extended position 46 near the prismatic battery cell 200 during the leak test, with the web portion 40 and the side portions 42 thereof enclosing at least a portion of the prismatic battery cell 200. The first guide 35 is advantageously positioned in the retracted position 48 away from the prismatic battery cell 200 to enable movement of the prismatic battery cell 200 into or out of the first environmental chamber 28 before and after the leak test.

[0046] The first gas delivery system 54 may be a CO2 gas delivery system capable of sealingly engaging a fill port 208 of an unfilled bag 206 of the prismatic cell 200 and displacing air contained in the unfilled bag 206 at a predetermined pressure for a period of time.

[0047] In one embodiment, the second test station 60 is a duplicate of the first test station 20.

[0048] The second test station 60 includes a second frame portion 62 with a base portion 63, opposing legs 64, 65, a first mounting post 66, a second mounting post 67, and a second environmental chamber 68. The second environmental chamber 68 is configured as a rectangular prism with transparent side and top portions and an open bottom portion. The second environmental chamber 68 is mounted on the second frame portion 62 and serves to create a static ambient airflow and thermal conditions around the prismatic battery cell 200 during testing.

[0049] The OGI system of the second inspection station 60 includes a second infrared camera 70 with a second optical lens filter 72, a second backdrop 75, a second mirror 90, a second vacuum source 92, and a second gas supply system 94. In one embodiment, the second gas supply system 94 is a CO2 gas supply system, and the second optical lens filter 72 is in the form of a CO2 optical lens filter. Alternatively, another gaseous substance may be used, with leak detection being performed by a corresponding imaging system.

[0050] The second infrared camera 70 communicates with the controller 120. The second infrared camera 70 is mounted on the first mounting column 66 such that it has a second field of view (FOV) 74 that encompasses the prismatic battery cell 200 during inspection. Location and mounting positions, working distances, angles, FOVs, and other parameters are application-specific and can be determined by those skilled in the art.

[0051] The second gate 75 is arranged as a second open channel 78, e.g., a C-channel, which is attached via a second controllable extension piece 85 to the second mounting post 67, to which a second heating element 76 is attached. In one embodiment, the second open-edged channel 78 is made of aluminum with a web portion 80 and side portions 82. The surface 84 of the second open channel 78 is treated to minimize or eliminate light reflection, particularly the reflection of infrared light. In one embodiment, the surface 84 of the second open channel 78 is black anodized to minimize the reflection of infrared light. The second mirror 90 is arranged on the second gate 75 in a corner between the web portion 80 and one of the side portions 82.The second heating element 76 is a silicon or positive temperature coefficient heater operatively connected to the controller 120 and controllable to maintain a stable thermal environment within the second environmental chamber 68 during the test. The second controllable extension device 85 can be configured to move the second backrest 75 to either a retracted position 88 or an extended position 86. In one embodiment, the second controllable extension device 85 is embodied as a pneumatic cylinder. The second gate 75 is advantageously positioned in the extended position 86 proximate the prismatic battery cell 200 during the leak test, with the web portion 80 and the side portions 82 thereof enclosing at least a portion of the prismatic battery cell 200.The second background 75 is advantageously positioned in the retracted position 88 away from the prismatic battery cell 200 to allow movement of the prismatic battery cell 200 into or out of the second environmental chamber 68 before and after the leak test.

[0052] The second gas delivery system 94 may be a CO2 gas delivery system capable of sealingly engaging a filling opening 208 of an unfilled bag 206 of the prismatic battery cell 200 and displacing the air contained in the unfilled bag 206 at a predetermined pressure for a certain time.

[0053] Fig. 4A schematically shows the first inspection station 20 with the first infrared camera 30 equipped with the first optical lens filter 32, wherein the first gate 35 is arranged in the retracted state.

[0054] Fig.4B schematically shows the first test station 20 with the first infrared camera 30, which is equipped with a first optical lens filter 32, wherein the first gate 35 is arranged in the extended state, ie in the test state.

[0055] Fig. 5 shows a leak detection routine 140 that may be implemented as one or more algorithms stored and executed in a non-volatile memory device of the controller 120 to detect the occurrence of a leak in an unfilled prismatic battery cell 200 using the leak test system 10 described with reference to FIG. Fig. 1, Fig. 2, Fig. 3, Fig. 4A and Fig.4B. Table 1 serves as a key, with the numerically labeled blocks and corresponding functions corresponding to the leak detection routine 140 being illustrated as follows. The teachings may be described herein in terms of functional and / or logical block components and / or various processing steps. It should be understood that such block components may consist of hardware, software, and / or firmware components configured to perform the specified functions. As shown, the leak detection routine 140 is illustrated as a collection of blocks in a logical flowchart representing a sequence of operations that may be implemented in hardware, software, or a combination thereof. In the context of software, the blocks represent computer instructions that, when executed by one or more processors, perform the stated operations. Table 1 BLOCK BLOCK CONTENT 141 Place cell at the first test station 142 expand the first backdrop 143 Pressurize cell with gas 144 Monitoring the cell with the first camera 145 detect a leak? 146 First scenery 147 Move cell to second station 148 Identify leak location 149 send in for repair 151 Place cell at the second test station 152 expand the second backdrop 153 Pressurize cell with gas 154 Monitoring the cell with a second camera 155 detect a leak 156 retract second backdrop 157 transit cell 158 Identify leak location 159 send in for repair

[0056] The execution of the leak detection routine 140 may proceed as follows. The steps of the routine 140 may be executed in any suitable order and are not limited to the steps described in Fig.5. The term "Y" here represents an affirmative answer, i.e., "YES," and the term "N" represents a negative answer, i.e., "NO." The leak detection routine 140 begins by arranging or otherwise placing an unfilled prismatic battery cell (cell) at the first test station (step 141) and arranging the first background in the first test position, with the first test position and thus the first background being proximate a first portion of the cell (step 142). The cell is pressurized using the first CO2 gas delivery system, including controlling the internal pressure of the cell's bag (step 143). Image capture by the camera is triggered when the pressure inside the bag reaches a predetermined minimum pressure.The first infrared camera monitors at least a first portion of the cell and the first baffle to detect or recognize the presence of CO2, which may indicate a leak (step 144). If the first infrared camera detects or recognizes the presence of CO2 (145)(Y), the location of a leak in the cell is identified (step 148), and the cell is excluded from further testing and sent offline for repair (step 149). If the first infrared camera does not detect the presence of CO2 (145)(N), the first baffle is retracted (step 146), and the cell is moved to the second station (step 147).

[0057] The leak detection routine 140 continues by placing or otherwise positioning the unfilled prismatic battery cell (cell) at the second test station (step 151) and placing the second backdrop in the second test position, with the second test position and thus the second backdrop being proximate a second portion of the cell (step 152). The cell is pressurized using the second CO2 gas delivery system, including controlling the internal pressure of the cell's bag (step 153). Image capture by the camera is triggered when the pressure inside the bag reaches a predetermined minimum pressure. The second infrared camera monitors at least a second portion of the cell and the second backdrop to detect or recognize the presence of CO2, which may indicate a leak (step 154).If the second infrared camera detects or recognizes the presence of CO2 (155)(Y), the location of a leak on the cell is identified (step 158), and the cell is removed from further testing and taken out of service for repair and process improvement to prevent further leak-related defects in manufacturing (step 159). If the second infrared camera does not detect the presence of CO2 (155)(N), the second shutter is retracted (step 156), and the cell passes the leak detection routine 140 and is forwarded for further processing (step 157).

[0058] The first infrared camera is arranged to monitor a first field of view that includes the first backdrop when the first backdrop is in a first test position. The second infrared camera is arranged to monitor a second field of view that includes the second background image when the second background image is in a second test position. The controller is in communication with the first test station, the second test station, and the conveyor. The controller includes a cell testing method captured in algorithmic code stored in non-volatile memory. The cell testing method includes the following steps: placing an unfilled prismatic battery cell (cell) at the first test station; placing the first backdrop and the first mirror in the first test position, the first test position being proximate a first portion of the cell;Pressurizing the cell using CO2 gas at the first test station; monitoring an outer portion of the first portion of the cell via the first infrared camera to detect the presence of CO2 gas; transporting the cell via the conveyor to the second test station; placing the second backdrop and the second mirror in the second test position, the second test position being proximate a second portion of the cell; pressurizing the cell with CO2 gas at the second test station; monitoring an outer portion of the second portion of the cell via the second infrared camera to detect the presence of CO2 gas; detecting, via the controller, a leak in the cell when the first infrared camera detects the presence of CO2 gas proximate the outer portion of the first portion of the cell;and detecting, via the controller, a leak in the cell when the second infrared camera detects a presence of CO2 gas near the outer part of the second part of the cell;

[0059] The terms controller, control module, module, controller, control unit, processor, and similar terms refer to various combinations of application-specific integrated circuits (ASICs), electronic circuits, central processing units, e.g., microprocessors, and associated non-volatile memory components in the form of memories and devices (read-only memory, programmable read-only memory, random access memory, hard disk, etc.). The non-volatile memory component is capable of storing machine-readable instructions in the form of one or more software or firmware programs or routines, combinational logic circuits, input / output circuits and devices, signal conditioning and buffer circuits, and other components that can be accessed by one or more processors to provide the described functionality.Input / output circuits and devices include analog-to-digital converters and related devices that monitor inputs from sensors, where such inputs are monitored at a preset sampling frequency or in response to a triggering event. Software, firmware, programs, instructions, control routines, code, algorithms, and similar terms refer to sets of instructions executable by the controller, including calibrations and lookup tables. Each controller executes control routine(s) to provide desired functions, including monitoring inputs from sensor devices and other networked controllers and executing control and diagnostic routines to control the operation of actuators. The routines can be executed periodically at regular intervals or in response to a triggering event.Communication between controllers and communication between controllers, actuators, and / or sensors can occur via a direct wired connection, a networked communication bus connection, a wireless connection, a serial peripheral interface bus, or any other suitable communication link. Communication involves the exchange of data signals in any suitable form, e.g., electrical signals over a conductive medium, electromagnetic signals over air, optical signals over fiber optics, and the like. Data signals can include signals representing inputs from sensors, signals representing actuator commands, and communication signals between controllers.

[0060] The concepts described here provide or enable an inline non-destructive testing (NDT) system that inspects individual prismatic cells during production and identifies leaks after the lid is welded to the can and before electrolyte filling. This technology can also pinpoint the leak location to optimize weld reprocessing. The system consists of two stations connected by a conveyor belt, with the prismatic cell first inspected at station 1 and then transported to station 2. Station 1 inspects the back and side edges of the cell, and station 2 inspects the front and side edges of the cell.

[0061] The flowcharts and block diagrams in the flowcharts illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flowcharts or block diagrams may represent a module, segment, or portion of code containing one or more executable instructions for implementing the specified logical function(s). It should also be understood that each block of the block diagrams and / or flowchart representations and combinations of blocks in the block diagrams and / or flowchart representations may be implemented by special-function hardware-based systems that perform the specified functions or acts, or by combinations of special-function hardware and computer instructions.These computer program instructions may also be stored in a computer-readable medium that can instruct a computer or other programmable data processing device to function in a particular manner such that the instructions stored in the computer-readable medium produce an article of manufacture including a set of instructions that implements the function / action specified in the flowchart and / or block diagram block or blocks.

Claims

[1] A leak testing system (10) comprising: a first test station (20), a second test station (60), a conveyor device (100) and a controller (120); wherein the first testing station (20) is connected to the second testing station (60) via the conveyor device (100); wherein the first inspection station (20) comprises a first infrared camera (30) equipped with a first optical CO2 lens filter (32), a first backdrop (35) with a first mirror (50) and a first CO2 gas supply system (54); wherein the second inspection station (60) comprises a second infrared camera (70) equipped with a second CO2 optical lens filter (72), a second backdrop (75) with a second mirror (90) and a second CO2 gas supply system (94); wherein the first infrared camera (30) is arranged to monitor a first field of view (34) including the first backdrop (35) when the first backdrop (35) is in a first test position; wherein the second infrared camera (70) is arranged to monitor a second field of view (74) including the second backdrop (75) when the second backdrop (75) is in a second test position; wherein the controller (120) is connected to the first test station (20), the second test station (60) and the conveyor device (100); wherein the controller (120) comprises a cell testing method captured in an algorithmic code stored in a non-volatile memory; wherein the cell testing procedure comprises the following steps: Placing (141) an unfilled prismatic battery cell (200), cell (200), at the first test station (20); Arranging the first backdrop (35) in the first test position, the first test position being located near a first portion of the cell (200); pressurizing (143) the cell (200) by means of the first CO2 gas supply system (54); Monitoring (144), via the first infrared camera (30), the cell (200) and the first backdrop (35); Transporting (147) the cell (200) via the conveyor device (100) to the second test station (60); Arranging the second backdrop (75) in the second test position, the second test position being located near a second portion of the cell (200); pressurizing (153) the cell (200) by means of the second CO2 gas supply system (94); Monitoring (154), via the second infrared camera (70), the cell (200) and the second backdrop (75); Detecting (145), via the controller (120), a leak in the cell (200) when the first infrared camera (30) detects CO2 gas in the vicinity of the cell (200); and Detecting (155), via the controller (120), a leak in the cell (200) when the second infrared camera (70) detects CO2 gas in the vicinity of the cell (200). [2] Leak testing system (10) according to claim 1, wherein the first gate (35) comprises: a first C-channel device (38) having a web portion (40), first and second side portions (42) and a heating element (36); wherein a surface (44) of the web portion (40) and the first and second side portions (42) of the first C-channel device (38) has an infrared light absorbing treatment; wherein the web portion (40) and the first and second side portions (42) are arranged to enclose the first portion of the cell (200) when the first gate (35) is arranged in the first test position. [3] The leak testing system (10) of claim 2, wherein the first C-channel device (38) is made of aluminum, and wherein the surface (44) of the web portion (40) and the first and second side portions (42) of the first C-channel device (38) has a black anodized surface (44). [4] Leak testing system (10) according to claim 2, wherein the second gate (75) comprises: a second C-channel device (78) having a web portion (80), first and second side portions (82) and a heating element (76); wherein a surface (84) of the web portion (80) and the first and second side portions (82) of the second C-channel device (78) has an infrared light absorbing treatment; wherein the web portion (80) and the first and second side portions (82) of the second C-channel device (78) are arranged to enclose the second portion of the cell (200) when the second gate (75) is arranged in the second test position. [5] The leak testing system (10) of claim 4, wherein the second C-channel device (78) is made of aluminum, and wherein the surface (84) of the web portion (80) and the first and second side portions (82) of the second C-channel device (78) has a black anodized surface (84). [6] The leak testing system (10) of claim 1, further comprising a first environmental enclosure and a second environmental enclosure, wherein the first test station (20) is disposed in the first environmental enclosure and wherein the second test station (60) is disposed in the second environmental enclosure. [7] The leak testing system (10) of claim 1, wherein the cell testing method further comprises a step of: Identifying (148), via the controller (120), a location of the leak at the cell (200) when the first infrared camera (30) detects the presence of CO2 gas in the vicinity of the cell (200). [8] The leak testing system (10) of claim 1, wherein the cell testing method further comprises a step of: Identifying (158), via the controller (120), a location of the leak at the cell (200) when the second infrared camera (70) detects the presence of CO2 gas in the vicinity of the cell (200). [9] Leak testing system (10) according to claim 1, wherein the first link (35) is attached to a first frame part (22) of the first test station (20) via a first extension piece (45); wherein the first extension piece (45) can be controlled into a retracted or an extended state; and wherein the cell testing method further comprises the following steps: Controlling (142) the first extension piece (45) into the extended state before the step of arranging the first gate (35) and the first mirror (50) in the first test position; and Controlling (146) the first extension piece (45) into the retracted state before the step (147) of transporting the cell (200) via the conveyor device (100) to the second test station (60). [10] Leak testing system (10) according to claim 9, wherein the second link (75) is attached to a second frame part (62) of the second test station (60) via a second extension piece (85); wherein the second extension piece (85) can be controlled into a retracted or an extended state; and wherein the cell testing method further comprises a step consisting of: Controlling (152) the second extension piece (85) into the extended state before the step of arranging the second link (75) and the second mirror (90) in the second test position.

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