System and method for automatically testing batteries and estimating their safety status using a test system.

Abstract

The systems, methods, and other embodiments described herein relate to testing used batteries by measuring signals until connection parameters for estimating a safe state are met. [Solution] In one embodiment, the method includes the step of measuring the s-parameters of a port of a used battery at a high frequency using a test apparatus. The method also includes the step of eliminating interference sources by calculating the first derivative of the real part from the impedance using the s-parameters, provided that the connection parameters associated with the port are met. The method also includes the step of estimating the safety status of the used battery from the change in the first derivative across a frequency band.

Description

[Technical Field]

[0001] Technical field The subject matter described herein generally relates to testing used batteries, and more specifically to testing used batteries by measuring signals using a test system until connection parameters for estimating a safe state are met. [Background technology]

[0002] background Drawing power from traction batteries in electric vehicles is a clean and sustainable alternative to burning fossil fuels, thereby reducing greenhouse gas emissions. EVs can also lower fuel and maintenance costs, improving economic value for consumers. However, traction batteries have a limited lifespan and negative environmental impacts. For example, disposal companies that handle traction batteries harm the environment with metallic waste. In the case of lithium-ion batteries, disposal can release toxic chemicals such as cobalt, nickel, and manganese into the soil and water. Traction batteries can also cause fires in landfills and recycling facilities, increasing air pollution and causing physical injury during handling. Therefore, systems that implement traction batteries in EVs face environmentally harmful consequences at the end of their product life (EoL).

[0003] Systems to mitigate the environmental impact of end-of-life (EOL) batteries include the repurposing and remanufacturing of used batteries. Repurposing applications may include installing used batteries from vehicles as backup power sources in homes. However, chemical decomposition and internal degradation associated with used batteries can limit their reuse applications. For example, lithium-ion batteries become covered in a plating during charging, where lithium ions are deposited as metallic lithium on the anode. This reduces battery performance by decreasing the amount of lithium available for energy storage, increases internal resistance, and creates safety hazards due to short circuits. Furthermore, systems testing used batteries to detect lithium plating face challenges due to the measurement task. Test equipment may require specialized probes and precise readings from used batteries. Such requirements can increase the cost of test equipment, potentially hindering reuse applications. Therefore, testing and reusing used EV batteries presents measurement and chemical defect-related obstacles, increasing costs and complexity, which impacts their repurposing applications. [Overview of the project] [Problems that the invention aims to solve]

[0004] overview In one embodiment, exemplary systems and methods relate to testing used batteries by measuring signals until connection parameters for estimating a safe state are met. In various implementations, the system measures the used battery using a cable (e.g., a coaxial cable) connected in parallel with the used battery to a test device. For example, the test equipment includes four contacts connected to all + / - terminals of the used battery (e.g., a battery module). However, these systems face measurement challenges in detecting battery degradation and wear without disassembly. In particular, in the case of plating detection, measurement uniformity of the input port may be required for accurate impedance values ​​that affect plating-related calculations. Thus, systems for testing used batteries for reuse and repurposing purposes face challenges with equipment configurations that reduce the reliability and certainty of the measurements. [Means for solving the problem]

[0005] Therefore, in one embodiment, the test system has test equipment and protocols specifically designed to automatically diagnose safety status at the module level rather than the cell level. In one measurement technique, the test system externally measures unitless s-parameters representing reflectance and loss during testing. In particular, the s-parameters may represent the reflectance and loss between the probe and the ports of the spent battery (e.g., output terminals, input terminals, etc.), thereby enabling the test system to obtain basic information about impedance. Furthermore, the system eliminates specific interference sources to reliably measure internal resistance from impedance at the module level using the s-parameters. This allows the test system to more easily estimate and diagnose safety status for second-life and reuse applications while avoiding invasive testing. In this way, the test system reliably and safely tests, measures, and detects degradation in spent batteries non-invasively, and identifies reuse applications for spent batteries that reduce environmental waste.

[0006] In one embodiment, a test system is disclosed for testing a used battery by measuring a signal until connection parameters for estimating a safe state are met. The test system includes a memory containing instructions, which, when executed by a processor, cause the processor to measure s-parameters for a port of the used battery at a high frequency using a test device. The instructions also include instructions for removing interference sources by calculating the first derivative of the real part from the impedance using the s-parameters once the connection parameters associated with the port are met. The instructions also include instructions for estimating a safe state for the used battery from the change in the first derivative across a frequency band.

[0007] In one embodiment, a non-transient computer-readable medium is disclosed for testing a used battery by measuring a signal until connection parameters for estimating a safe state are met. The non-transient computer-readable medium includes instructions that, when executed by a processor, cause the processor to perform one or more functions. The instructions include instructions for measuring s-parameters for a port of a used battery at a high frequency using a test device. The instructions also include instructions for removing interference sources by calculating the first derivative of the real part from the impedance using the s-parameters once the connection parameters associated with the port are met. The instructions also include instructions for estimating a safe state for the used battery from the change in the first derivative across a frequency band.

[0008] In one embodiment, a method is disclosed for testing a used battery by measuring a signal until connection parameters for estimating a safe state are met. In one embodiment, the method includes measuring s-parameters for the ports of the used battery at a high frequency using a test apparatus. The method also includes removing interference sources by calculating the first derivative of the real part from the impedance using the s-parameters once the connection parameters associated with the ports are met. The method also includes estimating a safe state for the used battery from the change in the first derivative across a frequency band.

[0009] Brief explanation of the drawing The accompanying drawings incorporated herein and constituting part thereof illustrate various systems, methods, and other embodiments of the present disclosure. Element boundaries illustrated in the drawings (e.g., boxes, groups of boxes, or other shapes) will be understood to represent one embodiment of the boundary. In some embodiments, one element may be designed as multiple elements, or multiple elements may be designed as one element. In some embodiments, an element shown as an internal component of another element may be realized as an external component, and vice versa. Furthermore, elements may not be drawn to scale. [Brief explanation of the drawing]

[0010] [Figure 1] This figure shows one embodiment of a test system that verifies connection parameters for testing used batteries and estimates the safety status of used batteries in relation to reuse and recycling applications. [Figure 2] This figure shows one embodiment of test equipment used by a test system to verify connections for electrical measurements and determine opportunities for battery reuse. [Figure 3] This figure shows an example of a used battery containing modules and cells that the test system will analyze. [Figure 4A]This figure shows an embodiment that verifies the port connections of a used battery by analyzing s-parameters and difference values. [Figure 4B] This figure shows an embodiment that verifies the port connections of a used battery by analyzing s-parameters and difference values. [Figure 5] This figure shows one embodiment of a method related to measuring the s-parameter of a port on a used battery and satisfying connection parameters for estimating a safe state. [Modes for carrying out the invention]

[0011] Detailed explanation Systems, methods, and other embodiments relating to testing used batteries by measuring signals until connection parameters for estimating a safe state are met are disclosed herein. In various implementations, testing a battery requires contact quality between cables and ports (e.g., output terminals, input terminals, etc.). For example, terminals from two coaxial cables require equivalent contact with the battery and contact verification. Otherwise, the test equipment will output incorrect measurements, reducing accuracy regarding significant degradation and internal condition. For example, detecting metal plating within cells without invasive probe inspection and disassembly requires accurate impedance derived from voltage and current measurements. In other words, systems may face difficulties in detecting plating and other degradation in batteries where the hardware and battery cells are tightly integrated. Another approach requires a system utilizing high-frequency electrochemical impedance spectroscopy (HF-EIS) to measure cell-level safe conditions and battery interference (e.g., contact interference, metal plating, etc.) from metallic materials (e.g., lithium ions). However, diagnosing the safety status of batteries at the cell level is expensive and complex, making such measurements costly and complex. Consequently, systems that test batteries using probes and cables for physical degradation and plating present challenges due to contact quality, complex equipment, and invasive disassembly, which reduces opportunities for reuse, increases costs, and generates more waste.

[0012] Therefore, in one embodiment, the test system measures s-parameters to automatically analyze the output current and capacity from a used battery, derives impedance from the s-parameters, and estimates the safety condition for improving reuse applications. In one method, the test system includes a protocol for evaluating the s-parameter measurements to assess the contact uniformity between the probe and the ports of the used battery (e.g., output terminals, input terminals, etc.). For example, the test system takes into account the reflection coefficient associated with the s-parameters from each port. This allows the test system to independently analyze the contact impedance of the ports via a capacitive-resistive parallel circuit from the s-parameters and reflection coefficient, thereby accurately identifying the contact quality for testing.

[0013] In various implementations, the test system calculates the difference between s-parameters in a high-frequency range (e.g., above 1 MHz). By automatically adjusting the port pressure to stay within acceptable limits, the test system can stabilize the connection between the spent battery and the measuring instrument, facilitating reproducible test evaluations. For example, an actuator changes the position of a probe with battery terminals in three-dimensional (3D) space to reduce resistance and reflection coefficients until the difference is minimized. The test system can utilize impeccable contact to diagnose safety conditions from impedance calculations. For example, the test system eliminates interference sources by calculating the first derivative of the real part of the impedance using s-parameters. This makes it possible to detect metal plating within cells (e.g., 12 cells) at the module level. In this way, the test system, by stabilizing the connection with the spent battery, saves costs by avoiding complex test equipment (e.g., the use of a spectrometer) for safety detection.

[0014] In certain implementations, the systems shown in Figures 1-5 also include various elements. In various embodiments, it will be understood that the system may have fewer elements than those shown in Figures 1-5. The system may have any combination of the various elements shown in Figures 1-5. Furthermore, the system may have additional elements in addition to those shown in Figures 1-5. In some configurations, the system may be implemented without one or more of the elements shown in Figures 1-5. Although the various elements are shown as being located within the system in Figures 1-5, it will be understood that one or more of these elements may be located outside the system. Furthermore, the illustrated elements may be physically separated by a wide distance. In addition, it will be noted that, for the sake of brevity and clarity of the examples, reference numbers are repeated in separate figures where necessary to indicate corresponding or similar elements. Furthermore, the description outlines numerous specific details to enable a full understanding of the embodiments described herein. However, those skilled in the art will understand that the embodiments described herein can be implemented using various combinations of these elements.

[0015] Referring to Figure 1, there is further illustrated one embodiment of the test system 100 of Figure 1. In order to evaluate the state of safety (SOS) of lithium-ion batteries and the like, a system that monitors, detects, etc., the internal growth of Li metal deposition is indispensable. The internal growth affects the thermal runaway temperature of the lithium-ion battery, thereby increasing safe reuse applications during mitigation. Such tests require reliable and repeatable contact between the test probe and the port for reliable measurements. Here, the test system 100 can measure s-parameters for the ports of a spent battery from a vehicle, and adjust the contact for impedance measurement. Furthermore, the test system 100 can identify the temperature and SOC by test equipment to optimally measure the impedance associated with the s-parameters related to internal state detection. For this reason, the measurement module 130 of the test equipment measures the impedance within a specific frequency band that indicates and highlights interference sources.

[0016] Furthermore, the test system 100 can remove interference sources by calculating the first derivative of the real part from the impedance and taking temperature and SOC into account. Furthermore, the test system 100 estimates the state of safety for the spent battery from the change of the first derivative within the frequency band. In one approach, the state of safety indicates degradation (e.g., chemical degradation, physical degradation, etc.) of one or more cells in a module associated with the spent battery.

[0017] In one embodiment, the test system 100 includes a memory 120 that stores a measurement module 130. The memory 120 is random-access memory (RAM), read-only memory (ROM), a hard disk drive, flash memory, or other suitable memory for storing the measurement module 130. The measurement module 130 is, for example, computer-readable instructions that, when executed by the processor 110, cause the processor 110 to perform various functions disclosed herein.

[0018] In Figure 1, the measurement module 130 generally includes instructions that function to control the processor 110 to receive data inputs from one or more sensors of the test equipment. For example, the test system 100 uses hardware that applies a minimal alternating current (AC) signal to a module, cell, etc. and measures the response, to identify s-parameters and measure impedance. Such test equipment can accurately output detailed information regarding the internal resistance and reactance of batteries such as high-voltage batteries used by EVs.

[0019] Further, in one embodiment, the test system 100 includes a data store 140. In one embodiment, the data store 140 is a database. The database, in one embodiment, is an electronic data structure stored in the memory 120 or another data store, and is composed of routines executable by the processor 110 to perform analysis of stored data, provision of stored data, organization of stored data, and the like. Thus, in one embodiment, the data store 140 stores data used by the measurement module 130 in performing various functions. In one embodiment, the data store 140 includes s-parameters 150, impedance 160, and battery characteristics 170. As described below, the s-parameters 150 may be unitless values related to electrical characteristics and responses associated with spent batteries. The impedance 160 may include a measure opposing electrical flow, expressed using complex value generalization and units of ohms (Ω). Therefore, impedance is similar to resistance in a direct current (DC) system. In AC systems, impedance incorporates reactance resulting from frequency-dependent contributions from capacitance and inductance. Impedance in AC systems is further measured in units of Ω by the formula Z=V / I, where V and I are frequency-dependent. Regarding the battery characteristics 170, this information may include safety conditions indicative of plating within cells, cell arrays, modules, etc. inside the spent battery.

[0020] In one method, the test system 100 and measurement module 130 include an instruction to the processor 110 to measure s-parameters 150 for the ports of a spent battery at high frequencies using a test device. Once the connection parameters associated with the ports are met, the test system 100 eliminates interference sources by calculating the first derivative of the real part from the impedance 160 using the s-parameters 150. As will be further described below, the test system 100 estimates the safety status of the spent battery from the change in the first derivative across the frequency band.

[0021] Figure 2 shows one embodiment of the test equipment 200 used by the test system 100. The test equipment 200 can verify and adjust connections for electrical measurements and predict battery reuse opportunities. In one method, the test system 100 uses a test device that detects degradation (e.g., internal plating) of a used battery 202 by calculating the first derivative of the real part from the impedance 160 using the s-parameter 150. Furthermore, using the s-parameter 150, if the connection parameters related to the port are satisfied, the test system 100 can estimate the safety status of the used battery 202 from the change in the first derivative across the frequency band. Here, the used battery 202 may be a lithium-ion battery, a solid-state battery, a magnesium battery, etc. A conveyor device 204 transports the used battery 202 for temperature and voltage measurement by a first probe 206 in the initial stage. In one method, the test system 100 signals an actuator 210 to automatically change the position of the first probe 206 (e.g., coaxial cable, electrical clip, clamp, etc.) to improve measurement fidelity. This may include the test system 100 optimally measuring the impedance 160 associated with the s-parameter 150, and the test system 100 identifying temperature and state of temperature (SOC) in order to detect the internal state.

[0022] For example, the test system 100 may include additional techniques to identify the optimal temperature, SOC, and impedance for detecting a safe state and remaining value. For instance, a test system 100 that measures impedance 160 at target temperature and SOC parameters improves the effectiveness of detecting degradation and calculating the safe state and remaining value using first derivative calculations. These parameter targets may depend on the internal architecture and chemical profile of the spent battery 202. The test system 100 can further improve calculation accuracy by adapting these parameter targets to reuse applications during impedance measurements of the spent battery 202.

[0023] Furthermore, in another method, the test system 100 selects a frequency band depending on the cell layout and internal architecture of the used battery 202 (e.g., cylindrical cells, laminated sheets, etc.). As described above, the frequency band can be associated with the test equipment that measures the impedance from the used battery 202 when the ion response within the cell is dominant. In addition, the test system 100 and the measurement module 130 can use the frequency band to filter out wear interference and measurement noise (e.g., sensor interference) on the used battery 202. In this way, the test system 100 can accurately diagnose the cause of impedance changes from measured values ​​and real parts of the first derivative for the cell at the module level, while reducing computational complexity.

[0024] The test equipment 200 may include a second probe 208 (e.g., coaxial cable, electrical clip, clamp, etc.) that uses a measurement module 130 to measure the s-parameters 150 and impedance 160. As described below, the test system 100 can observe the reflection coefficient between ports of the used battery 202. In one method, the test system 100 calculates the difference between the s-parameters 150 by taking into account the reflection coefficient at high frequencies, which indicates the connection quality between the second probe 208 and the ports (e.g., terminals) of the used battery 202. For example, the second probe 208 forms a capacitive-resistive parallel circuit from the s-parameters 150 and the reflection coefficient. This makes it possible for the test system 100 to detect an abnormal connection between the second probe 208 and the used battery 202.

[0025] Furthermore, the test system 100 can automatically adjust the pressure and connection strength on the port until the difference value falls within an acceptable range for the connection parameter. For example, the connection parameter may include either contact resistance or voltage reflection. Here, the adjustment may include moving the second probe 208 using the actuator 210 on the battery terminal. The movement can be performed in 3D space and can be done to reduce the resistance (e.g., contact resistance) and reflection coefficient until the difference value is minimized, a threshold is reached, etc. In this way, the test system 100 improves the fidelity of impedance measurement, degradation detection, and safety status.

[0026] In another example, the test equipment 200 acquires sensor data to detect defects in addition to degradation. Here, the test equipment 200 can acquire images related to the used battery 202 using a camera. In one method, the images capture changes in the formation or deformation of the casing of the used battery 202 (e.g., holes, color changes, etc.) with respect to a module detectable by the test system 100. Thus, the test equipment 200 using the test system 100 can detect changes in casing deformation using images for both external and internal testing.

[0027] The protocol related to Figure 2 may include determining battery characteristics 170. For example, battery characteristics 170 is a safety state indicating the internal plating of cells, cell arrays, modules, etc., inside the used battery 202, and the frequency band in which the plating becomes prominent. Alternatively, the safety state may include extracting operational quality with respect to specific safety-related characteristics of the used battery 202 (e.g., SOC, temperature, induction, etc.). As described above, plating may include forming a metallic layer on the anode surface of the cell due to improper intercalation of lithium ions into the anode material and the accumulation of lithium ions on the anode surface. The frequency band may exceed the frequency associated with increased chemical decomposition and increased ion response during testing of the used battery 202, thereby improving degradation detection.

[0028] The battery characteristics 170 may also include parameters related to safety status, indicating that one of the cells and modules within the used battery 202 has undetected plating on the anode surface related to a threshold (e.g., current output, voltage output, etc.). Furthermore, in one embodiment, the battery characteristics 170 include a State of Charge (SOC), which is one of the charge level and discharge level related to chemical degradation, a functional state for the used battery 202, a safety status, and weighting coefficients. For example, the functional state may be the residual value of the used battery 202 as a power source in a reuse application. As will be further described below, the residual value or functional state can be directly correlated with the safety status for the used battery 202.

[0029] In yet another embodiment, the test system 100 and measurement module 130 include instructions to the processor 110 to detect physical and chemical changes in the internal state of the battery (e.g., lithium-ion battery) from s-parameters and impedance measurements. In one method, detection requires a frequency band for impedance measurements exceeding frequencies where the ion response inside the battery is dominant (e.g., 100 Hz, 1 kHz, 1 MHz, etc.). This allows the test system 100 to accurately diagnose the cause of impedance changes from the first derivative and impedance values ​​for frequencies such as variable frequencies f1 to f2. The diagnosis may include one of the following: safety status, presence of lithium metal deposition, lithium plating in at least one battery cell, and residual value. For example, residual value may be the state of function (SOF), functional status, etc., related to the used battery 202 for reuse purposes. Therefore, residual value above minimum parameters, thresholds, etc., may indicate that the plating is sparse or absent in one or more cells within the used battery 202, thereby increasing the opportunity for reuse (212) rather than recycling (214) which generates waste. Otherwise, the remaining value may indicate that the used battery 202 is unsuitable and unsafe for reuse. The test system 100 may output a value indicating that the used battery 202 should be recycled.

[0030] In the test facility 200, the conveyor device 204 may route used batteries 202 for reuse (212) when the remaining value exceeds the minimum parameters, thresholds, etc., for reuse. In one method, this includes the test system 100 detecting mechanical deformation and cell displacement within the module of used batteries 202 from induced interference between an external object, such as a metal object, and contact tabs within the module. For example, mechanical deformation may be related to a vehicle-involved collision.

[0031] In one example, the test system 100 calculates the functional status of the used battery 202 using the safety status, weighting coefficients, and soundness status, where the functional status indicates the remaining value of the used battery 202 as a power source for reuse. Otherwise, if the safety status indicates plating within the cells of the modules inside the used battery 202, the conveyor device 204 routes the used battery 202 toward recycling (214) and disposal.

[0032] Furthermore, the test system 100 calculates the functional state from SOF, SOS, and SOH. For example, SOF is obtained by weighting SOS by SOH, forming equation (1). SOF = α × SOH × SOS Equation (1) The variable α may be a weighting coefficient that depends on one of the following: the battery's chemical properties, cell structure, casing material, application environment, or usage environment (e.g., commercial backup power supply, electric vehicle). In this regard, variable α improves the decision to reuse and resell by incorporating additional circumstances into the SOF of the used battery 202. For example, the test system 100 calculates the functional state, SOF, etc., of the used battery 202 using the safety condition, weighting coefficient, and SOH.

[0033] In equation (1), SOH can be a reuse dependency using a class, and can represent either the remaining capacity or the charge capacity of the used battery 202. For example, for a class related to vehicle reuse, a high SOH (e.g., 90%) is required for charge capacity, while for residential reuse, a lower SOH (e.g., 80%) may be acceptable. On the other hand, for critical facilities such as hospitals, an SOH exceeding 95% may be required. Therefore, the test system 100 can reliably output either a safety condition indicating deterioration such as metal plating, or a remaining value for the used battery 202. This allows downstream systems to automatically identify whether the used battery 202 is feasible for reuse, calculate the reuse value, and allocate the used battery 202 to a specific use by routing using the conveyor device 204. Otherwise, the used battery 202 is either defective, too worn to be repaired, or has limited market value, and the downstream system generates a recycling plan from the output.

[0034] Referring to Figure 3, an example of a used battery 202 in which a battery module 302 and battery cells 304 are embedded is shown, which is analyzed for degradation by a test system 100. In various implementations, the test system 100 measures the impedance 160 at the module level for the used battery 202 and performs calculations including the first derivative of the impedance 160. This makes it possible to eliminate interference sources that have a first derivative characteristic with respect to the impedance 160, which is invariant and negligible (e.g., zero). This may include mitigating induced interference from iron by calculating the second derivative from the impedance 160. Furthermore, estimating the safety condition for the used battery 202 may include calculating eddy interference using a linear relationship derived from the first derivative. As described below, this makes it possible to identify the plating within the used battery 202 from the difference between two values ​​of the first derivative using the test apparatus, without disassembling the cells associated with the used battery 202.

[0035] In one method, the test system 100 outputs a plating indication and a residual value for the used battery 202. Here, the residual value indicates the degree of the used battery 202 as a power source for reuse applications. This method also facilitates the estimation of the safety status and degradation (e.g., chemical degradation, physical degradation, etc.) of the battery cells 304 within the battery module 302 of the used battery 202 without invasive disassembly and expensive testing equipment. In this way, the method by the test system 100 reduces the complexity of the system.

[0036] In the examples presented herein, the test system 100 can also identify the plating of the terminals in the used battery 202 from the difference between two values ​​of the first derivative. This also allows the test system 100 to calculate the safety status of the used battery 202 without having to track the impedance from the time of manufacture and its initial state. For example, with third-party batteries, the high-frequency sensor that measures the impedance 160 in either the battery module 302 or the battery cell 304 can be omitted. In this way, the test system 100 can output the safety status and remaining value of the used battery 202, indicating its usability for reuse applications from various manufacturers.

[0037] With respect to Figures 4A and 4B, embodiments for verifying port connections by analyzing the s-parameter 150 and difference values ​​are shown. In Figure 4A, the test system 100 measures the s-parameter 150 using the negative port 410 and the positive port 420. Here, port A can be associated with either the first probe 206 side or the second probe 208 side, and port B represents the used battery 202 side. The test system 100 forms various circuits for measuring the unitless s-parameter 150. For example, Z C1a and Z C4a This forms a series circuit to determine the impedance 160 for the used battery 202 as the device under test (DUT). The DUT may also be one of the used battery 202, battery module 302, and battery cell 304.

[0038]

number

[0039]

number

[0040] FIG. 4B shows S 11 ~S 22 A normal connection between them has one of a linear waveform, a uniform waveform, a flat waveform, and the like. In other words, S 11 and S 22 The difference between them is constant (e.g., zero) and represents a positive or negative value. Here, the test system 100 performs contact evaluation for one of a high frequency range (e.g., greater than 1 MHz), a wide bandwidth (BW), etc., which alleviates the difficulties associated with equivalence evaluation. For example, the low frequency indicates the minimum absolute value that makes it impossible to evaluate the capacitive component from the contact impedance. Accordingly, the test system 100 uses the S in the high frequency range to accurately identify the safety state associated with the spent battery 202 11 and S 22 The difference value between them is utilized along with derivative calculation.

[0041] As described above, if the + / - terminals are precisely connected, S 11 and S 22 exhibit comparable values. S 11 and S 22 The abnormal connection 430 between them exhibits an offset (e.g., a bump, a value difference, etc.) at high frequencies. This indicates one of misalignment, improper connection, etc., between the second probe 208 of the test system 100 and the battery port. In one approach, the test system 100 reduces the offset by automatically adjusting the connection level by moving the second probe 208 using the actuator 210. This allows the test system 100 to adjust the port pressure to fall within an acceptable range, thereby stabilizing the connection between the spent battery 202 and the second probe 208, resulting in reproducible measurement evaluations. This adjustment also ensures that the contact resistance is minimized, thereby improving the estimation of the safety state. If a component (e.g., a module, a cell, etc.) has an unacceptable safety state due to metal plating, cell malfunction, or the like, the spent battery 202 is unusable and is recycled.

[0042] Continuing with Figures 4A and 4B, the test system 100, once the connection parameters are met, eliminates interference sources by calculating the first derivative of the real part from the impedance 160 using the s-parameter 150. As previously mentioned, the connection parameters include one of contact resistance or voltage reflection. Here, the test system 100 can calculate one or more of the following first derivatives from the impedance measurements associated with the spent battery 202. These first derivatives specifically include the first derivative of the real part from the impedance value, the first derivative of the imaginary part from the impedance value, the difference between the real parts from the first derivative of the impedance value between two frequency points, the difference between the imaginary parts from the first derivative of the impedance value between two frequency points, the real part of the impedance value, and the imaginary part of the impedance value. For example, the two frequency points are variable frequencies f1 to f2 within the frequency band, representing the increase in chemical decomposition and ionic response associated with the spent battery 202. This allows the test system 100 to reliably and non-invasively detect internal degradation and plating at the module level using first derivative calculations. Furthermore, the derivative calculation can be performed by filtering out noise-related impedance measurements by intelligently selecting the frequency band, taking into account the battery architecture and profile.

[0043] Alternatively, the test system 100 improves the effectiveness of detecting degradation and residual values ​​using first derivative calculations by measuring the impedance 160 at target temperature and SOC. These targets may depend on the internal architecture and chemical properties of the spent battery 202. Furthermore, the characteristics exhibited by the first derivative of the real part from impedance 160 are such that the test system 100 can target metal deposition and degradation (e.g., chemical degradation, physical degradation, etc.) by reducing interference sources. In the given example, the interference source can be associated with one of the cells, modules, cell arrays, etc., for the spent battery 202. Correspondingly, the test system 100 can accurately calculate the SOF for the spent battery 202 during the test while reducing interference.

[0044] The test system 100 can detect degradation of internal cells at the module level from the outside, avoiding invasive and complex testing. Here, the first derivative is used to neutralize, mitigate, eliminate, or remove contact interference (e.g., iron contacts, copper contacts, etc.) in the used battery 202 during impedance measurement by the second probe 208. Contact interference can originate from internal cells within the battery module 302 that are subject to loosening, tightening, etc., of couplings between terminals, contact tabs, etc. The difference between the real parts of the first derivative of the impedance values ​​between two frequency points allows for neutralization, mitigate, eliminate, or remove of inductive interference (e.g., iron-based induction).

[0045] In another example, the interference sources are inductive interference from iron and contact interference associated with one of the cells, modules, cell arrays, etc., within the used battery 202. Here, the test system 100 can convert the real part of the impedance 160 into a percentage value to minimize inductive interference (e.g., eddy currents) and to highlight the changes caused by metal plating by observing a linear relationship. This technique suppresses the test system 100 from using a monotonically increasing relationship in its calculations.

[0046] In various implementations, the test system 100 includes an analysis protocol for extracting contextual parameters related to the used battery 202. For example, when selecting thresholds for safety status and remaining value, the test system 100 takes into account the difference between the real parts of the first derivative of the impedance values ​​between two frequency points and contextual parameters. Here, the test system 100, which analyzes the remaining value, can diagnose other defects in addition to internal degradation, plating, etc. In one method, the threshold is associated with the plating level related to specific battery chemical properties (e.g., lithium-ion), usage profile (e.g., harsh weather, rough terrain, rough driving, etc.). This allows the test system 100 to improve the reliability and accuracy of the safety status and remaining value output by intelligently selecting thresholds.

[0047] In yet another example, the test system 100 estimates one of the safety status, SOF, and physical degradation of a used battery 202 by calculating eddy interference. For example, the test system 100 utilizes a linear relationship derived from the first derivative of the real part related to impedance measurements by a second probe 208. This allows the test system 100 to diagnose physical degradation as one of material wear and solid electrolyte interphase (SEI) growth. This allows the test system 100 to diagnose eddy currents from induced interference while avoiding complex test tasks.

[0048] In certain embodiments, the test system 100 detects the plating of terminals within the used battery 202 from the difference between two values ​​of the first derivative within a frequency band, without disassembling the cells. As described above, the test system 100 can calculate the safety status of the used battery 202 without tracking the impedance from the time of manufacture, provided that the cycle parameters are met. For example, the cycle parameters represent the number of cycles the used battery 202 has experienced and the extreme operating temperatures. This allows the test system 100 to output a safety status for the used battery, indicating its usability as a power source for reuse applications.

[0049] Regarding further details about interference sources, contact interference may arise from internal cells within the battery module 302 that experience loosening, tightening, etc., of the coupling between terminals. Coupling interference may arise from metallic material outside the spent battery 202 affecting one of the battery modules 302, battery cells 304, etc., within the spent battery 202. The test system can utilize the first derivative of the real part of the impedance 160, which varies between two or more frequency points, as an indicator of the interference source and its associated degree, without invasive test tasks.

[0050] The test system 100 can avoid complex testing by using target testing and first-derived function calculations to detect interference sources from the outside to internal cells at the module level. For example, the test system 100 uses first-derived function calculations to measure impedance 160 at target temperatures and SOCs that exhibit high chemical reactivity, improving the effectiveness of detecting degradation and residual values. A target SOC of 20% may represent low-priority residential reuse applications, while 85% may represent high-priority applications. Alternatively, these targets may depend on the internal architecture and chemical properties of the used battery 202. The test system 100 can adapt these targets to reuse applications that require the used battery 202, thereby further improving calculation accuracy.

[0051] In many ways, the first derivative can neutralize, mitigate, eliminate, or remove contact interference from the used battery 202 during impedance measurements across a selected frequency band. This contact interference may originate from internal cells within the battery module 302, subject to loosening, tightening, etc., of terminal couplings easily measurable within the frequency band. In one method, the test system 100 includes a negative port 410 and a positive port 420 as contact tabs between internal cells, modules, etc. The test system 100 may experience reduced reliability and accuracy due to contact interference during impedance measurements. Therefore, the test system 100 adjusts a second probe 208 using an actuator 210 located on either the negative port 410 or the positive port 420. For example, movement can be performed in 3D space to reduce resistance (e.g., contact resistance) and reflection coefficient until the difference value is minimized, a threshold is reached, etc. The test system 100 can also calculate the first derivative to eliminate contact interference from the used battery 202 during impedance measurements. In this way, the test system 100 improves the accuracy and reliability for detecting battery degradation and estimating safety status.

[0052] As described above, the test system 100 can convert the real part of the impedance 160 into a percentage value to minimize induced interference from eddy currents. This conversion can also magnify changes caused by metal plating by observing a linear relationship. Furthermore, the test system 100 and the measurement module 130 can necessarily filter out wear interference and measurement noise (e.g., sensor interference) to the used battery 202 by targeting a specific frequency band. In one method, the frequency band can be associated with the specific structure and manufacturing of the used battery 202. For example, the test system 100 performing impedance measurements will be affected below a certain frequency by a used battery 202 having one of the following: cylindrical wound cells, stacked plates, etc. Therefore, the test system 100 measuring above a certain frequency can eliminate wear and aging interference by taking the battery structure into account.

[0053] A test system 100 that calculates the difference between the real parts of the first derivative of the impedance value between two frequency points can neutralize, mitigate, eliminate, or remove inductive interference (e.g., iron-based induction). Here, external objects such as metals or magnets cause inductive interference with the battery module 302, battery cells 304, etc., during impedance measurement. For example, the battery cell 304 includes materials such as aluminum or stainless steel that inductively couple with external objects near the used battery 202. This coupling can also occur with polymers, plastics, etc., used as housings and shields for the battery module. In this way, the test system 100 that eliminates inductive interference can improve calculations of residual values ​​and safety conditions, including wear-related defects.

[0054] As described above, the test system 100 can detect mechanical deformation and displacement within the used battery 202 from inductive interference between an external object and either the negative port 410 or the positive port 420. This may include detecting cell displacement between cells within the battery module 302, where cells can be connected by either the negative port 410 or the positive port 420. Mechanical deformation can be caused by vehicle-involved collisions, accidents, external forces, impacts, module displacement, geometric cell changes, etc. Similar to metal plating, the test system 100 identifies and detects mechanical deformation and cell displacement while avoiding invasive techniques that could damage the battery hardware.

[0055] In various implementations, the test system 100 performs a second derivative calculation of impedance 160 (e.g., the real part of the impedance). This enhances the diagnosis of internal plating at the module level while eliminating and mitigating additional interference sources compared to the case of a first derivative calculation. Here, the second derivative can eliminate and reduce to zero induced interference from iron. This interference source has a first-order characteristic, which is a constant that allows the second derivative calculation of impedance 160 to cancel out its effect.

[0056] Furthermore, the second derivative also simplifies the removal of eddy currents from induction as an interference source by keeping the effect constant. For example, the test system 100 can reliably distinguish between internal plating and eddy currents affecting impedance measurements by the measurement module 130 by using second derivative calculations along with first derivative calculations. In this way, the test system 100 can reduce the influence of eddy currents when identifying internal degradation of the used battery 202.

[0057] The test system 100 can also filter out noise arising from derivative calculations. For example, the test system 100 targets a frequency band with optimal characteristics that enhance the plating effect, taking into account the cell arrangement. As with other methods, this example requires comparing the value of the second derivative from impedance measurements with a threshold for identifying internal plating in the battery module 302, battery cells 304, etc. Thus, the test system 100 accurately detects cell degradation in the used battery 202 by non-invasively optimizing s-parameters and derivative calculations while reducing the complexity of the test and damage to components.

[0058] Referring to Figure 5, a flowchart of Method 500 is shown, relating to measuring the s-parameter 150 for the ports of the used battery 202 and satisfying the connection parameters for estimating the safety status. Method 500 will be described in terms of the test system 100 in Figure 1. Although Method 500 is described in conjunction with the test system 100, it should be understood that it is not limited to being implemented within the test system 100, but is merely an example of a system in which Method 500 can be implemented.

[0059] In 510, the measurement module 130 measures s-parameters 150 for the ports of the used battery 202. These s-parameters 150 may be unitless values ​​relating to the electrical characteristics and response of the used battery 202. For example, the test system 100 observes the reflection coefficient between the ports of the used battery 202. Thus, the test system 100 calculates the difference between the s-parameters 150 by taking into account the reflection coefficient at high frequencies, which indicates the connection quality between the ports (e.g., terminals) of the used battery 202 and the test probe. The reflection coefficient can be associated with one of the voltages, currents, etc., observed between the ports (e.g., terminals) of the used battery 202 and the test probe. As described above, this allows the test system 100 to independently analyze the port contact impedance from the s-parameters 150 and the reflection coefficient using a capacitive-resistive parallel circuit, thereby enabling accurate identification of the contact quality for safety testing.

[0060] In 520, the test system 100 compares the s-parameters 150 with the connection parameters. As described above, the connection parameters include one of contact resistance and voltage reflection. Here, the test system 100 may automatically adjust the pressure and connection strength on the port until the difference between the s-parameters 150 falls within an acceptable range for the connection parameters. For example, as described above, the test system 100 utilizes the difference between the s-parameters 150 across the test probe and the battery port in the high-frequency range that increases either the connection resistance or interference. This includes additional measurements of the s-parameters 150 when the connection parameters are not met.

[0061] Furthermore, the adjustment may include moving the probe that measures the s-parameter 150 using an actuator on the battery terminal. Here, the movement can be performed in 3D space and can be done to reduce resistance (e.g., contact resistance) and reflection coefficient until the difference value is minimized, a threshold is reached, etc. This allows the test system 100 to adjust the port pressure to be within an acceptable range and stabilize the connection between the used battery 202 and the second probe 208. This enables reproducible measurement evaluation and ensures that contact resistance is minimized, thereby improving estimations of the safe state.

[0062] In 530, the test system 100 eliminates interference sources by calculating the first derivative of the real part from impedance 160 using the s-parameter 150. Here, the interference source can be associated with one of the cells, modules, cell arrays, etc., for the spent battery 202. In various implementation examples, the test system 100 measures the impedance 160 at the module level for the spent battery 202 and performs calculations including the first derivative of impedance 160. This makes it possible to eliminate interference sources that have first derivative characteristics for impedance 160 that are invariant and negligible (e.g., zero), such as contact interference. This may also include mitigating induced interference from iron by calculating the second derivative from impedance 160, which may exhibit a constant first derivative.

[0063] Furthermore, contact interference may originate from internal cells within the battery module that are subject to loosening, tightening, etc., of the coupling between terminals, which can be easily measured within the frequency band. In one method, the test system 100 has negative and positive ports between internal cells, modules, etc., as contact tabs. The test system 100 may experience reduced reliability and accuracy due to contact interference during impedance measurement. Furthermore, interference sources include inductive interference from iron and contact interference associated with one of the cells, modules, cell arrays, etc., within the used battery 202. Another interference source is measured above a certain frequency to eliminate interference from wear and aging by taking the battery structure into account.

[0064] In 540, the test system 100 estimates the safety status of the spent battery 202 from the change in the first derivative across a frequency band. For example, the test system 100 calculates the difference between the real parts of the first derivative of the impedance value between two frequency points, thereby neutralizing, mitigating, eliminating, or removing contact interference, inductive interference (e.g., iron-based induction), eddy interference, and aging interference. Here, external objects such as metals and magnets can cause inductive interference with battery cells, battery modules, etc., during impedance measurement. For example, battery cells include materials such as aluminum and stainless steel that inductively couple with external objects near the spent battery 202. Therefore, mitigating this interference improves the accuracy of the safety status calculation by the test system 100.

[0065] Furthermore, the test system 100 for estimating the safety status of the used battery 202 may include calculating eddy interference using a linear relationship derived from the first derivative. As mentioned above, this makes it possible to identify plating within the used battery 202 from the difference between two values ​​of the first derivative using the test system 100 without disassembling the cell. In this way, the test system 100 improves the calculation of the safety status by increasing the fidelity of impedance measurement and degradation detection, thereby improving measurement quality and mitigating various interference sources.

[0066] Detailed embodiments are disclosed herein. However, it should be understood that the disclosed embodiments are intended as examples. Accordingly, certain structural and functional details disclosed herein should not be construed as limiting, but merely as the basis for the claims and as representative grounds for teaching those skilled in the art to various forms of this specification to be adopted in substantially any appropriately detailed structure. Furthermore, the terms and phrases used herein are not intended to be limiting, but are intended to illustrate feasible implementation examples. Various embodiments are shown in Figures 1 to 5, but these embodiments are not limited to the illustrated structures or applications.

[0067] The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of feasible implementations of systems, methods, and computer program products according to various embodiments. In this regard, blocks in a flowchart or block diagram may represent modules, segments, or parts of code and contain one or more executable instructions for implementing a particular logical function. Note that in some alternative implementations, the functions described in a block may be performed in a different order than shown in the figure. For example, two blocks shown consecutively may actually be executed substantially simultaneously, or these blocks may sometimes be executed in reverse order depending on the functions involved.

[0068] The systems, components, and / or processes described above can be implemented in hardware or in combination of hardware and software, and can be implemented centrally in a single processing system or in a distributed form in which various elements are distributed across several interconnected processing systems. Any type of processing system or other device adapted to perform the methods described herein is suitable. A typical combination of hardware and software may be a processing system having computer-readable program code that, when loaded and executed, controls the processing system to perform the methods described herein.

[0069] Systems, components, and / or processes can also be embedded in computer-readable storage devices such as computer program products or other data program storage devices, and can perform the methods and processes described herein by tangibly embodying a program of machine-readable and machine-executable instructions. These elements can also be embedded in application products, which have features that enable the implementation of the methods described herein and, when loaded into a processing system, can perform these methods.

[0070] Furthermore, the configurations described herein may take the form of a computer program product embodied in one or more computer-readable media in which computer-readable program code is embodied (e.g., stored). Any combination of one or more computer-readable media may be used. A computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. The term "computer-readable storage medium" means a non-temporary storage medium. A computer-readable storage medium may be, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any preferred combination of those described above. More specific examples (non-exclusive list) of computer-readable storage media would include portable computer diskettes, hard disk drives (HDDs), solid-state drives (SSDs), ROMs, EPROMs, or flash memory, compact disc read-only memory (CD-ROMs), digital versatile discs (DVDs), optical storage devices, magnetic storage devices, or any preferred combination of those described above. In the context of this specification, a computer-readable storage medium can be any tangible medium on which a program can be embedded or stored for use by or with an instruction execution system, apparatus, or device.

[0071] In general, modules as used herein include routines, programs, objects, components, data structures, etc., that perform a particular task or implement a particular data type. In further embodiments, memory generally stores the modules mentioned. Memory associated with a module may be a processor, RAM, ROM, flash memory, or a buffer or cache embedded in another suitable electronic storage medium. In further embodiments, modules envisioned by this disclosure are implemented as ASICs, as hardware components of a system on a chip (SoC), as programmable logic arrays (PLAs), or as another suitable hardware component incorporating a defined set of configurations (e.g., instructions) for performing the disclosed functions.

[0072] Program code embodied on a computer-readable medium may be transmitted using any suitable medium, including but not limited to wireless, wired, optical fiber, cable, radio frequency (RF), or any preferred combination thereof. Computer program code for performing operations for this configuration may be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java®, Smalltalk®, and C++, and conventional procedural programming languages ​​such as the C programming language or similar languages. The program code may run entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or it may be connected to an external computer (for example, via the Internet using an Internet Service Provider).

[0073] As used herein, the term “one” is defined as one or more. As used herein, the term “plural” is defined as two or more. As used herein, the term “another” is defined as at least two or more. As used herein, the terms “contain” and / or “have” are defined as “equipped with” (i.e., open terms). As used herein, the phrase “at least one of… and…” refers to and encompasses any combination of one or more of the listed related items. For example, the phrase “at least one of A, B, and C” includes A, B, C, or any combination thereof (e.g., AB, AC, BC, or ABC).

[0074] The embodiments described herein can be embodied in other forms without departing from their spirit or essential attributes. Therefore, the appended claims, rather than the above-described specification, should be used as a reference to the scope of this specification.

Claims

1. It is a testing system, It includes memory for storing instructions, and when an instruction is executed by the processor, the processor Using a test apparatus, the s-parameters of the ports of used batteries at high frequencies are measured, When the connection parameters related to the port are satisfied, the interference source is removed by calculating the first derivative of the real part from the impedance using the s-parameters, A test system that estimates the safety status of a used battery from the change in the first derivative across a frequency band.

2. The instruction for measuring the s-parameter for the port is: A command for identifying the reflection coefficient between the aforementioned ports, The test system according to claim 1, further comprising instructions for calculating the difference between the s-parameters by taking into account the reflection coefficient at the high frequency.

3. The instruction for satisfying the aforementioned connection parameters is: The test system according to claim 2, further comprising instructions for the test apparatus to automatically adjust the pressure on the port until the difference value is within an acceptable range, wherein the connection parameter includes one of contact resistance and voltage reflection.

4. The instruction for estimating the safety status of the used battery is: Instructions for calculating eddy interference using the linear relationship derived from the first derivative, A command for identifying the plating inside the used battery from the difference between two values ​​of another first derivative using the test apparatus, without disassembling the cells associated with the used battery, The test system according to claim 2, comprising commands for displaying the plating and outputting a remaining value for the used battery, wherein the remaining value indicates the degree of the used battery as a power source for reuse applications.

5. The command for removing the interference source is: The test system according to claim 2, further comprising instructions for reducing inductive interference from iron by calculating the second derivative from the impedance.

6. A command to use a camera to acquire an image of the casing related to the used battery using the test device, The test system according to claim 1, further comprising: an instruction for detecting a change in deformation of the casing using the image described above, by the test apparatus.

7. The test system according to claim 1, further comprising commands for detecting mechanical deformation and cell displacement within the module from inductive interference between an external metallic object and contact tabs within the module of the used battery, wherein the mechanical deformation is related to a vehicle collision.

8. The method further includes instructions for calculating the functional status of the used battery using the safety status, weighting coefficients, and health status, wherein the functional status is the remaining value of the used battery as a power source for reuse applications. The test system according to claim 1, wherein the safety condition indicates the plating inside the cells of the module located inside the used battery.

9. A non-temporary computer-readable medium containing instructions, When the aforementioned instruction is executed by the processor, the processor will: Using a test apparatus, the s-parameters of the ports of used batteries at high frequencies are measured, When the connection parameters related to the port are satisfied, the interference source is removed by calculating the first derivative of the real part from the impedance using the s-parameters, A non-temporary computer-readable medium that enables estimation of the safety status of the used battery from the change in the first derivative across a frequency band.

10. The instruction for measuring the s-parameter for the port is: A command for identifying the reflection coefficient between the aforementioned ports, A non-temporary computer-readable medium according to claim 9, further comprising instructions for calculating the difference between the s-parameters by taking into account the reflection coefficient at the high frequency.

11. The instruction for satisfying the aforementioned connection parameters is: The non-transient computer-readable medium according to claim 10, further including instructions for the test apparatus to automatically adjust the pressure on the port until the difference value is within an acceptable range, wherein the connection parameter includes one of contact resistance and voltage reflection.

12. The instruction for estimating the safety status of the used battery is: Instructions for calculating eddy interference using the linear relationship derived from the first derivative, A command for identifying the plating inside the used battery from the difference between two values ​​of another first derivative using the test apparatus, without disassembling the cells associated with the used battery, A non-temporary computer-readable medium according to claim 10, comprising a display of the plating and an instruction for outputting a remaining value for the used battery, wherein the remaining value indicates the degree of the used battery as a power source for reuse applications.

13. It is a method, The steps include: measuring the s-parameter of the port of a used battery at a high frequency using a test apparatus; When the connection parameters related to the port are satisfied, the interference source is removed by calculating the first derivative of the real part from the impedance using the s-parameters. A method comprising the step of estimating the safety status of the used battery from the change in the first derivative over a frequency band.

14. The step of measuring the s-parameter for the port is: The steps include identifying the reflection coefficient between the ports, The method according to claim 13, further comprising the step of calculating the difference between the s-parameters by taking into account the reflection coefficient at the high frequency.

15. The steps that satisfy the aforementioned connection parameters are: The method according to claim 14, further comprising the step of automatically adjusting the pressure on the port by the test apparatus until the difference value is within an acceptable range, wherein the connection parameter includes one of contact resistance and voltage reflection.

16. The step of estimating the safety status of the used battery is: The steps include: calculating eddy interference using the linear relationship derived from the first derivative; Without disassembling the cells associated with the used battery, the step of identifying the plating in the used battery from the difference between two values ​​of another first derivative using the test apparatus, The method according to claim 14, comprising the steps of displaying the plating and outputting a remaining value for the used battery, wherein the remaining value indicates the degree of the used battery as a power source for reuse applications.

17. The step of removing the interference source is: The method according to claim 14, further comprising the step of reducing induced interference from iron by calculating the second derivative from the impedance.

18. The steps include: using a camera to acquire an image of the casing associated with the used battery using the test apparatus; The method according to claim 13, further comprising the step of detecting a change in deformation of the casing using the test apparatus with respect to the image.

19. The method of claim 13, further comprising the step of detecting mechanical deformation and cell displacement within the module from induced interference between an external object which is metal and a contact tab within the module of the spent battery, wherein the mechanical deformation is related to a vehicle collision.

20. The process further includes the step of calculating the functional status of the used battery using the safety status, weighting coefficient and health status, wherein the functional status is the remaining value of the used battery as a power source for reuse applications. The method according to claim 13, wherein the safety condition indicates plating within the cells of the module located inside the used battery.

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