Battery module voltage temperature acquisition integrated system based on die-cut FDC

Abstract

The application provides a battery module voltage temperature acquisition integrated system based on die cutting FDC, relates to the technical field of battery module state monitoring, and through application of a constant current to a die cutting temperature sensing section, real-time resistance characteristics are collected, the real-time resistance characteristics are mapped to a resistance temperature characteristic curve of the die cutting temperature sensing section, and a thermal state parameter of a cell pole is obtained; through correlation of the thermal state parameter and a nominal temperature coefficient of a reference voltage source in a voltage acquisition unit, a temperature drift offset is obtained, the temperature drift offset is reversely compensated and superimposed into the reference voltage source, a corrected reference voltage is obtained; through connection of a positive temperature sensing detection line and a negative sampling line to a high resistance sampling end of the voltage acquisition unit, a differential voltage response between the positive temperature sensing detection line and the negative sampling line is extracted according to the corrected reference voltage, and a cell voltage is determined. The application can perform temperature drift cooperative correction and sampling path control on a cell voltage temperature acquisition process, so as to improve voltage acquisition precision.

Description

Technical Field

[0001] This application relates to the field of battery module status monitoring technology, and more specifically, to an integrated system for acquiring battery module voltage and temperature based on die-cut FDC. Background Technology

[0002] Battery module status monitoring technology is widely used in new energy vehicle power battery packs, stationary energy storage power stations, and integrated photovoltaic-storage-charging systems. It is a necessary technical link to ensure the safe and stable operation of battery systems. The common implementation framework in this field usually adopts flexible acquisition components to set up sampling paths, collect voltage and temperature signals of the cell terminals, and transmit them to the management unit after signal conditioning and analog-to-digital conversion to realize continuous monitoring of the cell's operating status. This technology can support the charging and discharging control, safety early warning, and life management of battery systems.

[0003] However, in conventional battery module condition monitoring solutions, the reference value is easily affected by the ambient temperature, causing drift. Furthermore, the lack of a coordinated correction mechanism between temperature sensing and voltage sampling paths means that reference deviations caused by temperature changes cannot be effectively offset. This leads to systematic measurement deviations in cell voltage acquisition results as temperature fluctuates, reducing the accuracy and consistency of battery condition monitoring data across the entire temperature range. Therefore, how to implement coordinated temperature drift correction and sampling path control in the cell voltage and temperature acquisition process to improve voltage acquisition accuracy is a challenge facing the industry. Summary of the Invention

[0004] This application provides an integrated system for acquiring battery module voltage and temperature based on die-cut FDC, which can perform temperature drift correction and sampling path control during the battery cell voltage and temperature acquisition process to improve voltage acquisition accuracy.

[0005] In a first aspect, this application provides an integrated system for acquiring battery module voltage and temperature based on die-cut FDC, the integrated system comprising: A temperature sensing circuit construction module is used to die-cut a positive sampling line, a negative sampling line and a positive temperature sensing detection line on a die-cut FDC. The positive sampling line is provided with a die-cut temperature sensing section, which is connected to the voltage acquisition unit. The cell thermal state analysis module is used to apply a constant current to the die-cut temperature sensing section, collect the real-time resistive characteristics at both ends of the die-cut temperature sensing section, and map the real-time resistive characteristics onto the resistance-temperature characteristic curve of the die-cut temperature sensing section to obtain the thermal state parameters of the cell terminal. The reference voltage temperature drift compensation module is used to correlate the thermal state parameter with the nominal temperature coefficient of the reference voltage source in the voltage acquisition unit to obtain the temperature drift offset, and to inversely compensate and superimpose the temperature drift offset onto the reference voltage source to obtain the corrected reference voltage. The differential voltage acquisition module is used to disconnect the constant current, connect the positive electrode temperature sensing line and the negative electrode sampling line to the high-impedance sampling terminal of the voltage acquisition unit, extract the differential voltage response between the positive electrode temperature sensing line and the negative electrode sampling line based on the corrected reference voltage, and determine the cell voltage.

[0006] In this embodiment, applying a constant current to the die-cutting temperature sensing section and collecting the real-time resistive characteristics across the die-cutting temperature sensing section specifically includes: A constant current is applied to the die-cutting temperature sensing section to form a constant excitation current flowing through the die-cutting temperature sensing section; The real-time potential difference across the die-cutting temperature sensing section is collected to obtain the real-time voltage drop response corresponding to the current resistance value of the die-cutting temperature sensing section; The real-time resistive characterization of the die-cut temperature sensing section is determined based on the constant excitation current and the real-time voltage drop response.

[0007] In this embodiment, mapping the real-time resistive characteristics onto the resistance-temperature characteristic curve of the die-cut temperature sensing section to obtain the thermal state parameters of the cell terminal specifically includes: Call the resistance-temperature characteristic curve of the die-cut temperature sensing segment to determine the resistance-temperature mapping range corresponding to the real-time resistive characteristic in the resistance-temperature characteristic curve; Within the resistance-temperature mapping range, based on the correspondence between resistance and temperature in the resistance-temperature characteristic curve, the real-time resistive characteristics are converted to obtain the real-time temperature characterization value of the die-cutting temperature sensing segment. Based on the thermal coupling path between the die-cut temperature sensing section and the cell electrode, the real-time temperature characterization value is converted into the thermal state parameter of the cell electrode.

[0008] In this embodiment, determining the resistance-temperature mapping range corresponding to the real-time resistive characteristic in the resistance-temperature characteristic curve by calling the resistance-temperature characteristic curve of the die-cut temperature sensing segment specifically includes: The real-time resistive characteristics are smoothed in the time domain and temperature drift interference is removed to obtain steady-state resistive characterization values. Extract the set of segmented slope inflection points of the resistance-temperature characteristic curve, compare the steady-state resistivity characterization value with the set of segmented slope inflection points, and determine the candidate resistance-temperature mapping interval. The upper and lower boundary margins of the candidate resistance-temperature mapping interval are checked, and the resistance-temperature mapping interval is determined based on the resistance value landing point of the steady-state resistive characterization value.

[0009] In this embodiment, the thermal state parameter is correlated with the nominal temperature coefficient of the reference voltage source within the voltage acquisition unit to obtain the temperature drift offset, which specifically includes: Abnormal jumps in the thermal state parameters are eliminated to obtain effective thermal state parameters; Based on the temperature range in which the effective thermal state parameters fall, the nominal temperature coefficient of the reference voltage source in the corresponding temperature range is called. The effective thermal state parameter is converted to the nominal temperature coefficient, and the conversion result is limited and verified to obtain the temperature drift offset.

[0010] In this embodiment, the process of removing abnormal jumps in the thermal state parameters to obtain valid thermal state parameters specifically includes: Differential gradient extraction is performed on the thermal state parameters at adjacent sampling times to obtain the thermal state transition gradient sequence; Based on the deviation relationship between the thermal state transition gradient sequence and the preset transition threshold range, thermal state parameters that exceed the preset transition threshold range are eliminated to obtain effective thermal state parameters.

[0011] In this embodiment, the reverse compensation of the temperature drift offset is superimposed on the reference voltage source to obtain the corrected reference voltage, specifically including: Based on the polarity of the temperature drift offset, a reverse compensation voltage component is generated that is opposite to the temperature drift direction of the reference voltage source. The reverse compensation voltage component is superimposed on the reference output terminal of the reference voltage source to obtain the initial value of the compensated reference voltage. The initial value of the compensated reference voltage is subjected to output voltage range verification and ripple suppression processing to obtain the corrected reference voltage.

[0012] In this embodiment, superimposing the reverse compensation voltage component onto the reference output terminal of the reference voltage source to obtain the initial value of the compensated reference voltage specifically includes: The polarity matching verification of the reverse compensation voltage component is consistent with the temperature drift direction of the reference voltage source, and the real-time reference voltage amplitude of the reference output terminal is extracted to obtain the reference component to be superimposed. The reverse compensation voltage component and the reference component to be superimposed are differentially superimposed under common-mode suppression, and the superposition result is subjected to transient overshoot blanking to obtain the initial value of the compensated reference voltage.

[0013] In this embodiment, disconnecting the constant current and connecting the positive electrode temperature sensing line and the negative electrode sampling line to the high-impedance sampling terminal of the voltage acquisition unit specifically includes: A shutdown control command is applied to the constant current, and residual excitation discharge and potential stability detection are performed on the die-cut temperature sensing section to obtain an excitation shutdown confirmation state. In the excitation off confirmation state, the positive electrode temperature sensing line and the negative electrode sampling line are cut out from the excitation circuit and connected to the high-impedance sampling terminal of the voltage acquisition unit to form a high-impedance isolated sampling path.

[0014] In this embodiment, the differential voltage response between the positive electrode temperature sensing line and the negative electrode sampling line is extracted based on the corrected reference voltage, and the cell voltage is determined specifically by: The corrected reference voltage is sampled and synchronized with the timing and dynamically biased to obtain a sampling reference level that matches the high-impedance sampling terminal. Under the constraint of the sampling reference level, common-mode interference cancellation and temperature drift residual elimination are performed on the differential signal between the positive electrode temperature sensing line and the negative electrode sampling line to obtain the differential voltage response; The differential voltage response is subjected to full-scale verification and linearity correction, and the corrected differential voltage response is mapped to the cell terminal voltage range to determine the cell voltage.

[0015] The technical solutions provided by the embodiments disclosed in this application have the following beneficial effects: A positive sampling line, a negative sampling line, and a positive temperature sensing line are die-cut on a die-cut FDC. A die-cut temperature sensing section is provided on the positive sampling line and connected to a voltage acquisition unit. A constant current is applied to the die-cut temperature sensing section, and the real-time resistive characteristics at both ends of the section are acquired. These real-time resistive characteristics are mapped onto the resistance-temperature characteristic curve of the section to obtain the thermal state parameters of the cell terminals. The thermal state parameters are correlated with the nominal temperature coefficient of the reference voltage source within the voltage acquisition unit to obtain the temperature drift offset. This temperature drift offset is then inversely compensated and superimposed onto the reference voltage source to obtain a corrected reference voltage. The constant current is disconnected, and the positive temperature sensing line and the negative sampling line are connected to the high-resistance sampling terminal of the voltage acquisition unit. Based on the corrected reference voltage, the differential voltage response between the positive temperature sensing line and the negative sampling line is extracted, and the cell voltage is determined.

[0016] Therefore, in this application, the differential voltage response between the positive electrode temperature sensing line and the negative electrode sampling line can be extracted based on the corrected reference voltage, and the cell voltage can be determined. Specifically, determining the thermal state parameters allows for the acquisition of accurate temperature data that accurately reflects the actual thermal state of the cell electrode, overcoming the shortcomings of insufficient matching between temperature sensing and sampling reference drift and conduction deviations in existing technologies. This provides accurate temperature input for the temperature drift correction of the reference voltage, ensuring that the temperature drift compensation amount accurately matches the current actual operating temperature, avoiding compensation inaccuracies caused by temperature sensing deviations, effectively improving the matching accuracy and response timeliness of temperature drift compensation, ensuring the stability of the voltage acquisition reference across the entire temperature range, and providing support for improving the accuracy of cell voltage acquisition from the temperature input perspective. By determining the corrected reference voltage, a stable sampling reference standard after temperature drift reverse compensation can be obtained. This overcomes the shortcomings of existing technologies where the reference voltage source is affected by temperature and the sampling reference deviation accumulates with temperature. In this way, the systematic measurement error introduced by temperature changes is offset from the source of sampling, so that the voltage sampling reference remains stable and accurate throughout the entire operating temperature range. This effectively reduces the interference of ambient temperature fluctuations on the cell voltage acquisition results and improves the consistency and reliability of voltage acquisition data under different temperature conditions.

[0017] In summary, the technical solution adopted in this application can perform temperature drift correction and sampling path control during the battery cell voltage and temperature acquisition process, thereby improving the voltage acquisition accuracy. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only for this embodiment of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a module structure diagram of an integrated system for acquiring battery module voltage and temperature based on die-cut FDC, provided in this application. Figure 2 This is a flowchart illustrating the determination of thermal state parameters provided in this application; Figure 3 This is a schematic diagram of the battery module voltage and temperature acquisition principle based on die-cut FDC provided in this application. Detailed Implementation

[0020] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] This application provides an integrated system for acquiring battery module voltage and temperature based on a die-cut FDC. The core of this system involves die-cutting a positive electrode sampling line, a negative electrode sampling line, and a positive electrode temperature sensing line onto the die-cut FDC. A die-cut temperature sensing section is provided on the positive electrode sampling line and connected to a voltage acquisition unit. A constant current is applied to the die-cut temperature sensing section, and the real-time resistive characteristics at both ends of the section are acquired. These real-time resistive characteristics are mapped onto the resistance-temperature characteristic curve of the section to obtain the thermal state parameters of the cell terminals. The thermal state parameters are correlated with the nominal temperature coefficient of the reference voltage source within the voltage acquisition unit to obtain the temperature drift offset. This temperature drift offset is then inversely compensated and superimposed onto the reference voltage source to obtain a corrected reference voltage. The constant current is disconnected, and the positive electrode temperature sensing line and the negative electrode sampling line are connected to the high-resistivity sampling terminal of the voltage acquisition unit. Based on the corrected reference voltage, the differential voltage response between the positive electrode temperature sensing line and the negative electrode sampling line is extracted, and the cell voltage is determined.

[0022] To better understand the above technical solutions, a detailed description of the technical solutions will be provided below in conjunction with the accompanying drawings and specific embodiments. (Refer to...) Figure 1 As shown in the figure, this is a module structure diagram of an integrated system for acquiring voltage and temperature of a battery module based on die-cut FDC according to this embodiment of the present application. The integrated system includes: a temperature sensing circuit construction module 100, a cell thermal state analysis module 200, a reference voltage temperature drift compensation module 300, and a differential voltage acquisition module 400, which are described below: The temperature sensing circuit construction module 100 is used to form a positive sampling line, a negative sampling line, and a positive temperature sensing detection line on a die-cut FDC. The positive sampling line is provided with a die-cut temperature sensing section, which is connected to the voltage acquisition unit.

[0023] In practice, a precision die-cutting process is used to shape the PI insulating substrate with copper foil. The substrate uses a PI film as the insulating base, and a conductive copper foil of a predetermined thickness is laminated on one side. The die-cutting uses a custom steel mold that matches the preset circuit pattern to ensure that the circuit edges are smooth and burr-free. During processing, excess copper foil areas on the surface of the substrate are removed by die-cutting, and three electrically insulated independent conductive paths are integrally formed on the same die-cut FDC: a positive sampling line, a negative sampling line, and a positive temperature sensing line. Insulation spacing that meets design requirements is maintained between each line. In the preset section of the positive sampling line, a continuous copper foil structure with a predetermined line width and length is maintained by controlling the die-cutting dimensions. The cross-sectional dimensions and length parameters of this section of copper foil are precisely controlled, thus forming the die-cut temperature sensing section, giving this section of copper foil stable resistance-temperature characteristics. After completing the die-cutting of the circuit pattern, the substrate undergoes shape punching and insulating layer lamination to obtain the formed die-cut FDC acquisition component. Subsequently, riveting or welding processes are used to connect the two leads of the die-cut temperature sensing section to the constant current excitation interface and voltage detection interface of the voltage acquisition unit, respectively.

[0024] It should be noted that, in this application, the positive sampling line refers to the conductive path on the positive side of the die-cut FDC, used to transmit the cell voltage signal and carry the excitation current for temperature sensing; the negative sampling line refers to the conductive path on the negative side of the die-cut FDC, used to transmit the cell negative voltage signal, forming a complete voltage acquisition circuit; the positive temperature sensing line refers to the conductive path on the die-cut FDC, used to couple the cell electrode temperature and participate in the differential acquisition of cell voltage; the die-cut temperature sensing section refers to the designated copper foil section formed on the positive sampling line, which has stable temperature resistance characteristics and is used to convert the temperature into a detectable resistance characteristic; the voltage acquisition unit refers to a circuit module with reference voltage generation, signal acquisition and processing functions, used for cell voltage acquisition and temperature drift compensation.

[0025] The cell thermal state analysis module 200 is used to apply a constant current to the die-cut temperature sensing section, collect the real-time resistive characteristics at both ends of the die-cut temperature sensing section, and map the real-time resistive characteristics onto the resistance-temperature characteristic curve of the die-cut temperature sensing section to obtain the thermal state parameters of the cell electrode.

[0026] In this embodiment, applying a constant current to the die-cutting temperature sensing section and collecting the real-time resistive characteristics across the die-cutting temperature sensing section can be achieved in the following manner: A constant current is applied to the die-cutting temperature sensing section to form a constant excitation current flowing through the die-cutting temperature sensing section; The real-time potential difference across the die-cutting temperature sensing section is collected to obtain the real-time voltage drop response corresponding to the current resistance value of the die-cutting temperature sensing section; The real-time resistive characterization of the die-cut temperature sensing section is determined based on the constant excitation current and the real-time voltage drop response.

[0027] In practice, firstly, the constant current source circuit inside the voltage acquisition unit outputs a stable DC constant current, which is injected into the conductive circuit of the die-cut temperature sensing section through a preset sampling electrical path. The current direction remains constant, and the amplitude is selected within the normal reasonable range for copper conductor resistance temperature detection, effectively avoiding detection deviations caused by conductor self-heating due to excessive excitation current. The current flows through the entire conductive cross-section of the die-cut temperature sensing section, forming a stable constant excitation current in the circuit. Then, the high-impedance voltage detection port of the voltage acquisition unit is connected in parallel to both ends of the die-cut temperature sensing section. Differential sampling is used to acquire the real-time potential difference between the two ends of the die-cut temperature sensing section. The input impedance of the detection port is much higher than the resistance value of the die-cut temperature sensing section to avoid sampling shunt affecting measurement accuracy. The acquired analog voltage signal is converted into a digital signal by the analog-to-digital converter module, obtaining a real-time voltage drop response corresponding one-to-one with the current actual resistance value of the die-cut temperature sensing section. The sampling frequency is adapted to the normal rate of change of the cell temperature. Finally, based on the fundamental calculation model of Ohm's law, using the nominal amplitude of the constant excitation current as the denominator and the acquired real-time voltage drop response value as the numerator, a division operation is performed to obtain the real-time resistance value of the die-cut temperature sensing segment. This resistance value is then used as the real-time resistive characterization quantity. During the calculation process, multiple consecutive sets of sampled data can be arithmetically averaged to suppress random noise interference and output a stable real-time resistive characterization quantity.

[0028] It should be noted that in this application, constant excitation current refers to a DC current with stable amplitude injected in series into the die-cut temperature sensing section; real-time potential difference refers to the potential difference generated at both ends of the die-cut temperature sensing section under the action of excitation current; real-time voltage drop response refers to the digital quantity of voltage drop across the die-cut temperature sensing section obtained by sampling and conversion; and real-time resistive characterization refers to the real-time resistance value calculated based on the excitation current and voltage drop.

[0029] Preferably, in this embodiment, the real-time resistive characteristics are mapped onto the resistance-temperature characteristic curve of the die-cut temperature sensing section to obtain the thermal state parameters of the cell terminal, with reference to... Figure 2 As shown in the figure, this is a schematic flowchart of determining thermal state parameters in some embodiments of this application. In this embodiment, the determination of thermal state parameters can be achieved by the following steps: In step S21, the resistance-temperature characteristic curve of the die-cut temperature sensing segment is called to determine the resistance-temperature mapping range corresponding to the real-time resistive characteristic in the resistance-temperature characteristic curve. In step S22, within the resistance-temperature mapping range, based on the correspondence between resistance and temperature in the resistance-temperature characteristic curve, the real-time resistive characteristics are converted to obtain the real-time temperature characterization value of the die-cutting temperature sensing segment. In step S23, the real-time temperature characterization value is converted into the thermal state parameter of the battery cell electrode according to the thermal coupling path between the die-cut temperature sensing section and the battery cell electrode.

[0030] In practice, firstly, the resistance-temperature characteristic curve of the die-cut temperature sensing segment is pre-stored as discrete calibration data points in the non-volatile storage medium of the voltage acquisition unit. The data points are arranged in ascending order of resistance value, completely covering the entire temperature range of normal cell operation. After calling the resistance-temperature characteristic curve, the currently acquired real-time resistive characteristic is used as input. All calibration data points are traversed sequentially to locate two sets of adjacent calibration nodes with resistance values ​​greater than and less than the real-time resistive characteristic. The temperature range defined by these two sets of nodes is the resistance-temperature mapping interval corresponding to the real-time resistive characteristic. Then, within the determined resistance-temperature mapping interval, a linear interpolation algorithm is used to complete the conversion from resistance to temperature. The resistance and temperature values ​​corresponding to the calibration nodes at both ends of the interval are taken as the calculation basis. Let the resistance of the low-resistance node be R1 and the corresponding temperature be T1, and the resistance of the high-resistance node be R2 and the corresponding temperature be T2. The real-time resistive characteristic R1 is then calculated. x Substituting into the linear interpolation formula, the corresponding temperature value T is obtained. x This represents the real-time temperature characterization value of the die-cut temperature sensing section. The copper conductor exhibits good linearity in its resistance-temperature characteristics within the normal operating temperature range. Finally, the die-cut temperature sensing section and the cell electrode form a stable thermal coupling path through a bonding connection structure. Under steady-state heat conduction, there is a fixed temperature correspondence between the two, which is pre-calibrated and stored in the acquisition unit. The calculated real-time temperature characterization value is used as input and substituted into a preset thermal coupling conversion relationship to correct for heat conduction deviations, eliminating the temperature difference caused by the thermal resistance between the sensing section and the electrode, thus obtaining thermal state parameters that accurately reflect the true temperature of the cell electrode.

[0031] It should be noted that, in this application, the resistance-temperature characteristic curve refers to the calibration curve showing the relationship between the resistance value of the die-cut temperature sensing section and its temperature; the cell terminal refers to the conductive output structure at the end of the cell, which provides electrical connection points for the sampling circuit and transmits information about the internal thermal state of the cell; the resistance-temperature mapping range refers to the temperature segment on the resistance-temperature characteristic curve that contains the current real-time resistive characteristics of adjacent calibration points; the real-time temperature characterization value refers to the real-time temperature value of the die-cut temperature sensing section obtained by resistance-temperature mapping conversion; the thermal coupling path refers to the heat conduction path between the die-cut temperature sensing section and the cell terminal; and the thermal state parameter refers to the physical parameter of the real-time temperature state of the cell terminal.

[0032] In addition, in this embodiment, determining the resistance-temperature mapping range corresponding to the real-time resistive characteristic in the resistance-temperature characteristic curve by calling the resistance-temperature characteristic curve of the die-cut temperature sensing segment can be achieved by the following steps: The real-time resistive characteristics are smoothed in the time domain and temperature drift interference is removed to obtain steady-state resistive characterization values. Extract the set of segmented slope inflection points of the resistance-temperature characteristic curve, compare the steady-state resistivity characterization value with the set of segmented slope inflection points, and determine the candidate resistance-temperature mapping interval. The upper and lower boundary margins of the candidate resistance-temperature mapping interval are checked, and the resistance-temperature mapping interval is determined based on the resistance value landing point of the steady-state resistive characterization value.

[0033] In practice, the continuously acquired real-time resistive characteristic sequence undergoes time-domain smoothing using a fixed-window-length moving average filtering algorithm. The window length is selected as 5 to 10 sampling periods, and the arithmetic mean of all sampled resistance values ​​within the window is calculated to suppress random high-frequency noise during the sampling process. After smoothing, temperature drift interference is eliminated using a first-order differential threshold method. The resistance change between adjacent smoothed data points is calculated, and when the change exceeds a preset normal fluctuation threshold, it is identified as an interference point and replaced with the previous valid steady-state value, outputting a stable steady-state resistive characterization value. Then, the resistance-temperature characteristic curve is pre-divided into segments according to the slope change pattern. The connection endpoints of each segment are the slope inflection points. All inflection points are arranged in ascending order of resistance value to form a segmented slope inflection point set. The resistance and temperature parameters corresponding to each inflection point are pre-calibrated fixed values. Using the steady-state resistive resistance value as input, a binary search algorithm is employed to compare it against a set of segmented slope inflection points. The steady-state resistance value is compared with the resistance values ​​at each inflection point to quickly locate two adjacent inflection points containing the current steady-state resistance value. The segment defined by these two inflection points is the candidate resistance-temperature mapping interval. Finally, the upper and lower boundary resistance values ​​of the candidate resistance-temperature mapping interval are obtained, and the differences between the steady-state resistive resistance value and the upper and lower boundary resistance values ​​are calculated. Upper and lower boundary margin checks are then performed. A reasonable boundary margin threshold is preset. When the difference between the steady-state resistance value and any boundary is less than the margin threshold, it is determined to be a boundary near-terminal state. The interval is then expanded by one inflection point in the corresponding direction and re-checked. After successful check, if the steady-state resistive resistance value falls within the valid range of the interval, that interval is determined as the resistance-temperature mapping interval.

[0034] It should be noted that, in this application, time-domain smoothing refers to a noise suppression process for time-series resistive sampling data; temperature drift interference removal is used to filter out slow-changing drift and instantaneous outliers in the resistive sampling data; steady-state resistive characterization value refers to the stable resistance value data obtained after smoothing and interference removal; the piecewise slope inflection point set refers to the ordered set of slope change boundary points on the resistance-temperature characteristic curve; interval comparison refers to matching and judging the steady-state resistive value with the curve inflection point resistance value to achieve preliminary screening and positioning of candidate mapping intervals; candidate resistance-temperature mapping interval refers to the resistance value interval to be verified obtained through preliminary comparison; upper and lower boundary margin verification refers to the process of verifying the reasonableness of the distance between the candidate interval boundary and the target resistance value; resistance value landing point refers to the corresponding position of the steady-state resistive characterization value on the resistance-temperature characteristic curve.

[0035] The reference voltage temperature drift compensation module 300 is used to correlate the thermal state parameter with the nominal temperature coefficient of the reference voltage source in the voltage acquisition unit to obtain the temperature drift offset, and to inversely compensate and superimpose the temperature drift offset onto the reference voltage source to obtain the corrected reference voltage.

[0036] In this embodiment, the temperature drift offset is obtained by associating the thermal state parameter with the nominal temperature coefficient of the reference voltage source in the voltage acquisition unit using the following steps: Abnormal jumps in the thermal state parameters are eliminated to obtain effective thermal state parameters; Based on the temperature range in which the effective thermal state parameters fall, the nominal temperature coefficient of the reference voltage source in the corresponding temperature range is called. The effective thermal state parameter is converted to the nominal temperature coefficient, and the conversion result is limited and verified to obtain the temperature drift offset.

[0037] In specific implementation, firstly, the time sequence of continuously output thermal state parameters is acquired, and anomaly jump rejection is performed using a differential threshold method. Based on the known characteristics of large thermal inertia of the battery cell and a physical upper limit to the rate of temperature change, a maximum reasonable temperature change threshold is preset within a unit sampling period. The threshold value balances interference filtering and normal temperature change identification. The absolute value of the difference between the current thermal state parameter and the previous valid parameter is calculated point by point. When the difference exceeds the preset threshold, it is determined as an abnormal jump point, and the previous valid parameter is used to replace the abnormal value. The remaining data is directly retained, outputting stable valid thermal state parameters. Then, based on the nominal parameters of the reference voltage source, the temperature range is divided into multiple continuous, non-overlapping temperature intervals. Each interval corresponds to a fixed set of nominal temperature coefficients, and all interval boundaries and corresponding coefficient parameters are stored in the non-volatile storage medium of the voltage acquisition unit. The valid thermal state parameters are compared sequentially with the upper and lower boundary values ​​of each temperature interval to determine the target temperature interval into which the valid thermal state parameter falls, and the corresponding nominal temperature coefficient for that interval is retrieved. Finally, using the nominal reference temperature of the reference voltage source as the calculation benchmark, the difference between the effective thermal state parameter and the nominal reference temperature is calculated. This temperature difference is then multiplied by the retrieved nominal temperature coefficient to preliminarily calculate the temperature drift offset. Subsequently, a limiting verification is performed. The upper and lower thresholds of the offset are pre-set based on the maximum temperature drift parameter of the reference voltage source. If the preliminary calculation result exceeds the threshold range, the output value is clamped to the corresponding boundary value, and the temperature drift offset that meets the amplitude constraint is output.

[0038] It should be noted that, in this application, the reference voltage source refers to the reference voltage generating circuit set inside the voltage acquisition unit; the nominal temperature coefficient refers to the nominal parameter that quantifies the degree of change of the output voltage of the reference voltage source with temperature; abnormal jump rejection is used to filter out instantaneous abnormal change data in the thermal state parameters; the effective thermal state parameters refer to the temperature parameters after abnormal jump rejection processing; the amplitude limit verification refers to the boundary amplitude constraint on the temperature drift conversion result to ensure that the output compensation amount is within a reasonable working range; the temperature drift offset refers to the value of the deviation of the output voltage of the reference voltage source caused by temperature change.

[0039] In addition, in this embodiment, the abnormal jumps in the thermal state parameters are eliminated to obtain effective thermal state parameters, which can be achieved by the following steps: Differential gradient extraction is performed on the thermal state parameters at adjacent sampling times to obtain the thermal state transition gradient sequence; Based on the deviation relationship between the thermal state transition gradient sequence and the preset transition threshold range, thermal state parameters that exceed the preset transition threshold range are eliminated to obtain effective thermal state parameters.

[0040] In practice, firstly, time-series data of thermal state parameters output at a fixed sampling period is acquired. The sampling period is selected based on the thermal inertia characteristics of the battery cell, choosing a conventional temperature sampling range to ensure that the data accurately reflects the continuous temperature change trend. Differential gradient extraction is performed on the time-series data. The thermal state parameter at the current sampling moment is compared with the thermal state parameter at the previous adjacent sampling moment, and the resulting temperature change is divided by the sampling period length to obtain the temperature change rate value at the corresponding moment. This operation is performed point-by-point on the entire time-series data to obtain a thermal state jump gradient sequence arranged in the order of sampling moments. Then, a jump threshold range is preset. The upper and lower limits of the range correspond to the maximum allowable heating rate and the maximum allowable cooling rate under normal battery cell operation, respectively. The thresholds are set based on the physical characteristics of the battery cell's thermal capacity and thermal conductivity. Each gradient value in the thermal state jump gradient sequence is compared with the preset jump threshold range to determine the deviation relationship between the two. When the gradient value exceeds the threshold interval boundary, the thermal state parameter at the corresponding time is determined to be abnormal jump data and is removed. The valid parameter at the previous time is used as the current valid value. If the gradient is within the interval, the original parameter is retained and the valid thermal state parameter is output.

[0041] It should be noted that, in this application, differential gradient extraction refers to the process of converting thermal state parameters into rate of change indicators; thermal state jump gradient sequence refers to a data set composed of the temperature change rates at each sampling time in sequence; preset jump threshold interval refers to the numerical range that defines the normal temperature change rate; deviation relationship refers to the state where the thermal state jump gradient exceeds the threshold interval.

[0042] It should also be noted that in this application, the preset jump threshold range can be set in the following way: based on the thermophysical characteristics of the battery cell and the sampling period parameters, the upper limit of the range corresponds to the maximum allowable heating rate under normal operating conditions of the battery cell, and the lower limit of the range corresponds to the maximum allowable cooling rate. The battery cell has a fixed heat capacity and thermal conductivity impedance. Temperature changes are limited by the heating during charging and discharging and the environmental heat exchange rate. During normal operation, there is a clear physical upper limit to the temperature change within a unit sampling period. Combined with the normal rate of change of battery cell charging and discharging and environmental temperature fluctuations in practical applications, a reasonable range of threshold values ​​can be determined. The threshold range setting takes into account both abnormal interference filtering and normal temperature change identification, with reasonable margins at the boundaries. This ensures effective elimination of instantaneous jumps caused by sampling interference without falsely filtering out normal temperature fluctuations of the battery cell. Finally, the threshold is solidified as a judgment parameter and stored in the voltage acquisition unit.

[0043] In this embodiment, the reverse compensation of the temperature drift offset is superimposed on the reference voltage source to obtain the corrected reference voltage. This can be achieved in the following way: Based on the polarity of the temperature drift offset, a reverse compensation voltage component is generated that is opposite to the temperature drift direction of the reference voltage source. The reverse compensation voltage component is superimposed on the reference output terminal of the reference voltage source to obtain the initial value of the compensated reference voltage. The initial value of the compensated reference voltage is subjected to output voltage range verification and ripple suppression processing to obtain the corrected reference voltage.

[0044] In practice, firstly, the temperature drift offset of the calculated output is obtained. The polarity of this offset is then identified: a positive offset represents a positive drift of the reference voltage source output voltage relative to its nominal value at the current temperature, while a negative offset represents a negative drift. Based on the fundamental principle of temperature drift cancellation, the temperature drift offset is inverted to generate a reverse compensation voltage component, which is completely opposite to the temperature drift direction of the reference voltage source. The amplitude of this component is equal to the absolute value of the temperature drift offset, but its polarity is opposite. Then, the reference output terminal is the electrical node where the reference voltage source outputs its nominal reference voltage, carrying the function of superimposing and correcting the reference voltage output. The processing module inside the voltage acquisition unit performs an algebraic superposition operation on the nominal reference voltage value output by the reference voltage source and the reverse compensation voltage component. The superposition process follows the algebraic addition rule of voltage quantities, and the polarity of the reverse compensation voltage component directly determines the direction of increase or decrease in the superposition operation. After the operation is completed, the initial value of the reference voltage after preliminary temperature drift compensation is obtained at the reference output terminal. Finally, the initial reference voltage value is first checked for output voltage range. Reasonable upper and lower threshold values ​​are pre-set based on the rated output range of the reference voltage source. The initial reference voltage value is compared with these thresholds. If the initial value exceeds the threshold range, it is clamped to the corresponding boundary value to ensure the output is within the normal operating range. After range checking, ripple suppression processing is performed. A first-order low-pass digital filter algorithm is used to smooth the continuously output initial reference voltage value, suppressing small fluctuations generated during the compensation adjustment process and outputting a stable corrected reference voltage.

[0045] It should be noted that, in this application, reverse compensation superposition refers to superimposing a compensation component opposite to the temperature drift direction of the reference voltage source onto the reference output terminal to offset the reference voltage deviation caused by temperature drift; the reverse compensation voltage component refers to a voltage correction amount that is opposite to the temperature drift direction of the reference voltage source and matches its amplitude; the reference output terminal refers to the electrical node where the reference voltage source outputs the nominal reference voltage; the initial value of the reference voltage refers to the reference voltage value after preliminary superposition of reverse compensation; the output voltage range verification refers to constraining the output range of the reference voltage to avoid the reference voltage exceeding the normal operating range due to compensation abnormalities; ripple suppression processing refers to the process used to smooth out small fluctuations in the reference voltage and improve the stability and sampling reference accuracy of the output reference voltage; the corrected reference voltage refers to the reference voltage after temperature drift compensation, range verification, and ripple suppression.

[0046] In addition, in this embodiment, the reverse compensation voltage component is superimposed on the reference output terminal of the reference voltage source to obtain the initial value of the compensated reference voltage, which can be achieved by the following steps: The polarity matching verification of the reverse compensation voltage component is consistent with the temperature drift direction of the reference voltage source, and the real-time reference voltage amplitude of the reference output terminal is extracted to obtain the reference component to be superimposed. The reverse compensation voltage component and the reference component to be superimposed are differentially superimposed under common-mode suppression, and the superposition result is subjected to transient overshoot blanking to obtain the initial value of the compensated reference voltage.

[0047] In specific implementation, firstly, the reverse compensation voltage component of the calculated output is acquired, and a polarity matching check is performed. The temperature drift direction of the reference voltage source at the current temperature is determined, and the polarity of the reverse compensation voltage component is verified to be opposite to the temperature drift direction. If the polarity does not match, a polarity reversal correction is performed on the compensation component. After successful verification, the valid compensation component is retained. Simultaneously, the current output voltage value at the reference output terminal is acquired, and the real-time reference voltage amplitude is extracted. This amplitude is used as the reference component to be superimposed in the compensation superposition operation. Then, the reference component to be superimposed and the reverse compensation voltage component are connected to a differential operation circuit. Under the common-mode rejection mechanism, the common-mode interference component shared by the two signals is filtered out, and only the valid differential-mode components are subjected to algebraic superposition to obtain a preliminary superposition result. Transient overshoot blanking is performed on the preliminary superposition result. A fixed-duration amplitude clamping window is set to clamp voltage spikes exceeding the steady-state range generated during compensation switching to a reasonable range, eliminating transient fluctuations and obtaining the initial value of the compensated reference voltage.

[0048] It should be noted that, in this application, polarity matching verification refers to the process of verifying the accuracy of the compensation polarity of the reverse compensation voltage component; real-time reference voltage amplitude refers to the actual output voltage value of the reference output terminal at the current moment; the reference component to be superimposed refers to the real-time reference voltage quantity extracted from the reference output terminal; common-mode rejection refers to the process of filtering out the interference components common to the two signals in the superposition operation, thereby improving the anti-interference capability and operation accuracy of the compensation operation; differential superposition refers to performing the superposition operation of the compensation component and the reference component based on the differential operation architecture; transient overshoot blanking refers to the process of suppressing the voltage spike fluctuation generated at the moment of compensation superposition.

[0049] The differential voltage acquisition module 400 is used to disconnect the constant current, connect the positive electrode temperature sensing line and the negative electrode sampling line to the high-impedance sampling terminal of the voltage acquisition unit, extract the differential voltage response between the positive electrode temperature sensing line and the negative electrode sampling line based on the corrected reference voltage, and determine the cell voltage.

[0050] In this embodiment, disconnecting the constant current and connecting the positive electrode temperature sensing line and the negative electrode sampling line to the high-impedance sampling terminal of the voltage acquisition unit can be done in the following way: A shutdown control command is applied to the constant current, and residual excitation discharge and potential stability detection are performed on the die-cut temperature sensing section to obtain an excitation shutdown confirmation state. In the excitation off confirmation state, the positive electrode temperature sensing line and the negative electrode sampling line are cut out from the excitation circuit and connected to the high-impedance sampling terminal of the voltage acquisition unit to form a high-impedance isolated sampling path.

[0051] In practice, firstly, the control module of the voltage acquisition unit outputs a shutdown control command to the internal constant current source circuit, cutting off the constant current output path injected into the die-cut temperature sensing section. Simultaneously, the discharge branch connected in parallel across the die-cut temperature sensing section is turned on, and residual excitation discharge is applied to the line and temperature sensing section through the discharge resistor, accelerating the potential drop-off speed. After the discharge continues for a preset duration, potential stability detection is performed, periodically acquiring the potential values ​​across the die-cut temperature sensing section. When the potential fluctuation amplitude is lower than the preset stability threshold for multiple consecutive sampling periods, it is determined that the excitation has been completely removed and the potential is stable, generating an excitation shutdown confirmation state. Then, triggered by the excitation shutdown confirmation state, the voltage acquisition unit controls the internal multi-channel analog switch to perform a path switching operation, first completely disconnecting the positive temperature sensing line and the negative sampling line from the original constant current excitation circuit, breaking all electrical connections between them and the excitation circuit. Subsequently, the two sampling lines are connected to the two high-impedance sampling terminals corresponding to the voltage acquisition unit, so that the sampling lines and the high input impedance detection ports form a reliable electrical connection, forming a high-impedance isolated sampling path with high input impedance characteristics, and completing the smooth switching from excitation mode to voltage sampling mode.

[0052] It should be noted that, in this application, the high-impedance sampling terminal refers to the sampling interface of the voltage acquisition unit with extremely high input impedance; the shutdown control command refers to the control signal that controls the constant current source circuit to stop outputting constant current; residual excitation discharge refers to releasing the residual charge on the sampling line, accelerating the potential fall back, and eliminating the interference of residual excitation on sampling; potential stability detection is used to monitor the potential fluctuation state of the sampling line and determine whether the potential has reached the stable condition after the excitation is removed; the excitation shutdown confirmation state is a state indicator that the constant current has been completely turned off and the potential is stable; the excitation circuit cut-out is to disconnect the sampling line from the constant current excitation path to achieve electrical isolation between the excitation circuit and the sampling circuit; the high-impedance isolated sampling path refers to the voltage acquisition path composed of the high-impedance sampling terminal and the sampling line.

[0053] In this embodiment, the differential voltage response between the positive electrode temperature sensing line and the negative electrode sampling line is extracted based on the corrected reference voltage, and the cell voltage is determined by the following steps: The corrected reference voltage is sampled and synchronized with the timing and dynamically biased to obtain a sampling reference level that matches the high-impedance sampling terminal. Under the constraint of the sampling reference level, common-mode interference cancellation and temperature drift residual elimination are performed on the differential signal between the positive electrode temperature sensing line and the negative electrode sampling line to obtain the differential voltage response; The differential voltage response is subjected to full-scale verification and linearity correction, and the corrected differential voltage response is mapped to the cell terminal voltage range to determine the cell voltage.

[0054] In specific implementation, firstly, the update timing of the corrected reference voltage is synchronized with the sampling timing of the analog-to-digital converter (ADC) start clock at the high-impedance sampling terminal. This ensures that the update time of the reference level is strictly aligned with the sampling trigger time, preventing sampling errors caused by timing misalignment. After synchronization, dynamic bias locking is performed. Based on the effective range of the input common-mode voltage at the high-impedance sampling terminal, the DC bias of the corrected reference voltage is adjusted in real time to ensure that the reference level is always within the linear operating range of the ADC. After the bias parameter is locked, the output sampling reference level matches that of the high-impedance sampling terminal. Then, under the reference constraint of the sampling reference level, the high-impedance sampling terminal acquires the original differential signal between the positive temperature sensing line and the negative sampling line. First, common-mode interference cancellation is performed. The differential amplification structure cancels out the in-phase interference components such as ground potential drift and spatial electromagnetic interference shared by the two signals, retaining the effective differential-mode signal. Then, temperature drift residual elimination is performed. Combining the current thermal state parameters and the pre-stored sampling channel temperature drift residual calibration parameters, a secondary deviation correction is performed on the differential-mode signal to eliminate the influence of residual temperature drift in the channel, resulting in the differential voltage response. Finally, a full-scale calibration is performed on the differential voltage response, comparing it to the rated full-scale range of the sampling channel. Data exceeding the range is marked as invalid, while data within the range enters the calibration process. Linearity calibration is then performed. Based on the pre-calibrated nonlinear error curve of the sampling channel, piecewise linear interpolation is used to compensate for the differential voltage response error, correcting the nonlinear deviation of the channel transmission. The corrected differential voltage is then mapped to the cell terminal voltage range according to the sampling gain and voltage division ratio, and the cell voltage is calculated.

[0055] It should be noted that, in this application, differential voltage response refers to the potential difference signal between the two sampling lines after interference cancellation and temperature drift residual correction; sampling timing synchronization refers to the process of aligning the reference voltage update and sampling trigger time to eliminate the influence of timing deviation on voltage sampling accuracy; dynamic bias locking refers to the process of adjusting the DC bias of the reference voltage to match the optimal input range of the sampling port; sampling reference level refers to the reference voltage after timing synchronization and bias adjustment; common-mode interference cancellation refers to the process of canceling the common in-phase interference components in the sampling path; temperature drift residual elimination refers to the process of correcting the residual temperature drift deviation of the sampling channel; full-scale calibration refers to determining whether the differential voltage response is within the effective range of the sampling channel; linearity correction refers to the process of compensating for the nonlinear transmission error of the sampling channel and improving the accuracy of differential voltage measurement results; cell terminal voltage range refers to the process of measuring the range of the actual voltage between the positive and negative terminals of the cell; cell voltage refers to the actual potential difference between the positive and negative terminals of the cell obtained after correction and range conversion.

[0056] In this embodiment, reference Figure 3 As shown in the figure, this is a schematic diagram of the voltage and temperature acquisition principle of a battery module based on die-cut FDC (Flexible DC Distributor). The FDC flexible sheet serves as the front-end sampling carrier, on which sampling lines and temperature sensing structures are formed through a die-cutting process. These directly couple the voltage signal and thermal state information of the cell terminals and transmit the acquired raw electrical signal to the voltage acquisition unit. The voltage acquisition unit is the core processing module of the system, establishing electrical signal connections with the resistance-temperature characteristic data module, the reference voltage source, and the temperature drift compensation module. The resistance-temperature characteristic data module outputs pre-calibrated resistance-temperature mapping parameters to the voltage acquisition unit, providing a calibration basis for the conversion calculation from resistance to temperature. The reference voltage source provides a reference for voltage sampling for the voltage acquisition unit; its output voltage exhibits inherent drift characteristics with ambient temperature. After completing temperature conversion and temperature drift offset calculation, the voltage acquisition unit transmits the sampled signal and reference correction parameters to the temperature drift compensation module. After compensation and correction, the final cell voltage detection result is output.

[0057] Therefore, in this application, the differential voltage response between the positive electrode temperature sensing line and the negative electrode sampling line can be extracted based on the corrected reference voltage, and the cell voltage can be determined. Specifically, determining the thermal state parameters allows for the acquisition of accurate temperature data that accurately reflects the actual thermal state of the cell electrode, overcoming the shortcomings of insufficient matching between temperature sensing and sampling reference drift and conduction deviations in existing technologies. This provides accurate temperature input for the temperature drift correction of the reference voltage, ensuring that the temperature drift compensation amount accurately matches the current actual operating temperature, avoiding compensation inaccuracies caused by temperature sensing deviations, effectively improving the matching accuracy and response timeliness of temperature drift compensation, ensuring the stability of the voltage acquisition reference across the entire temperature range, and providing support for improving the accuracy of cell voltage acquisition from the temperature input perspective. By determining the corrected reference voltage, a stable sampling reference standard after temperature drift reverse compensation can be obtained. This overcomes the shortcomings of existing technologies where the reference voltage source is affected by temperature and the sampling reference deviation accumulates with temperature. In this way, the systematic measurement error introduced by temperature changes is offset from the source of sampling, so that the voltage sampling reference remains stable and accurate throughout the entire operating temperature range. This effectively reduces the interference of ambient temperature fluctuations on the cell voltage acquisition results and improves the consistency and reliability of voltage acquisition data under different temperature conditions.

[0058] In summary, the technical solution adopted in this application can perform temperature drift correction and sampling path control during the battery cell voltage and temperature acquisition process, thereby improving the voltage acquisition accuracy.

[0059] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0060] Those skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, including read-only memory (ROM), random access memory (RAM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), one-time programmable read-only memory (OTPROM), electrically-Erasable Programmable Read-Only Memory (EEPROM), compactdisc read-only memory (CD-ROM) or other optical disc storage, disk storage, magnetic tape storage, or any other computer-readable medium capable of carrying or storing data.

[0061] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

Claims

1. An integrated system for acquiring battery module voltage and temperature based on die-cut FDC, characterized in that, The integrated system includes: A temperature sensing circuit construction module is used to die-cut a positive sampling line, a negative sampling line and a positive temperature sensing detection line on a die-cut FDC. The positive sampling line is provided with a die-cut temperature sensing section, which is connected to the voltage acquisition unit. The cell thermal state analysis module is used to apply a constant current to the die-cut temperature sensing section, collect the real-time resistive characteristics at both ends of the die-cut temperature sensing section, and map the real-time resistive characteristics onto the resistance-temperature characteristic curve of the die-cut temperature sensing section to obtain the thermal state parameters of the cell terminal. The reference voltage temperature drift compensation module is used to correlate the thermal state parameter with the nominal temperature coefficient of the reference voltage source in the voltage acquisition unit to obtain the temperature drift offset, and to inversely compensate and superimpose the temperature drift offset onto the reference voltage source to obtain the corrected reference voltage. The differential voltage acquisition module is used to disconnect the constant current, connect the positive electrode temperature sensing line and the negative electrode sampling line to the high-impedance sampling terminal of the voltage acquisition unit, extract the differential voltage response between the positive electrode temperature sensing line and the negative electrode sampling line based on the corrected reference voltage, and determine the cell voltage.

2. The integrated system for acquiring battery module voltage and temperature based on die-cut FDC as described in claim 1, characterized in that, Applying a constant current to the die-cutting temperature sensing section and collecting the real-time resistive characteristics across the die-cutting temperature sensing section specifically includes: A constant current is applied to the die-cutting temperature sensing section to form a constant excitation current flowing through the die-cutting temperature sensing section; The real-time potential difference across the die-cutting temperature sensing section is collected to obtain the real-time voltage drop response corresponding to the current resistance value of the die-cutting temperature sensing section; The real-time resistive characterization of the die-cut temperature sensing section is determined based on the constant excitation current and the real-time voltage drop response.

3. The integrated system for acquiring battery module voltage and temperature based on die-cut FDC as described in claim 1, characterized in that, Mapping the real-time resistive characteristics onto the resistance-temperature characteristic curve of the die-cut temperature sensing section yields the thermal state parameters of the cell terminal, specifically including: Call the resistance-temperature characteristic curve of the die-cut temperature sensing segment to determine the resistance-temperature mapping range corresponding to the real-time resistive characteristic in the resistance-temperature characteristic curve; Within the resistance-temperature mapping range, based on the correspondence between resistance and temperature in the resistance-temperature characteristic curve, the real-time resistive characteristics are converted to obtain the real-time temperature characterization value of the die-cutting temperature sensing segment. Based on the thermal coupling path between the die-cut temperature sensing section and the cell electrode, the real-time temperature characterization value is converted into the thermal state parameter of the cell electrode.

4. The integrated system for acquiring battery module voltage and temperature based on die-cut FDC as described in claim 3, characterized in that, The determination of the resistance-temperature mapping range corresponding to the real-time resistive characteristic in the resistance-temperature characteristic curve by calling the resistance-temperature characteristic curve specifically includes: The real-time resistive characteristics are smoothed in the time domain and temperature drift interference is removed to obtain steady-state resistive characterization values. Extract the set of segmented slope inflection points of the resistance-temperature characteristic curve, compare the steady-state resistivity characterization value with the set of segmented slope inflection points, and determine the candidate resistance-temperature mapping interval. The upper and lower boundary margins of the candidate resistance-temperature mapping interval are checked, and the resistance-temperature mapping interval is determined based on the resistance value landing point of the steady-state resistive characterization value.

5. The integrated system for acquiring battery module voltage and temperature based on die-cut FDC as described in claim 1, characterized in that, The thermal state parameter is correlated with the nominal temperature coefficient of the reference voltage source within the voltage acquisition unit to obtain the temperature drift offset, which specifically includes: Abnormal jumps in the thermal state parameters are eliminated to obtain effective thermal state parameters; Based on the temperature range in which the effective thermal state parameters fall, the nominal temperature coefficient of the reference voltage source in the corresponding temperature range is called. The effective thermal state parameter is converted to the nominal temperature coefficient, and the conversion result is limited and verified to obtain the temperature drift offset.

6. The integrated system for acquiring battery module voltage and temperature based on die-cut FDC as described in claim 5, characterized in that, The effective thermal state parameters are obtained by removing anomalous jumps from the aforementioned thermal state parameters, specifically including: Differential gradient extraction is performed on the thermal state parameters at adjacent sampling times to obtain the thermal state transition gradient sequence; Based on the deviation relationship between the thermal state transition gradient sequence and the preset transition threshold range, thermal state parameters that exceed the preset transition threshold range are eliminated to obtain effective thermal state parameters.

7. The integrated system for acquiring battery module voltage and temperature based on die-cut FDC as described in claim 1, characterized in that, The reverse compensation of the temperature drift offset is superimposed onto the reference voltage source to obtain the corrected reference voltage, specifically including: Based on the polarity of the temperature drift offset, a reverse compensation voltage component is generated that is opposite to the temperature drift direction of the reference voltage source. The reverse compensation voltage component is superimposed on the reference output terminal of the reference voltage source to obtain the initial value of the compensated reference voltage. The initial value of the compensated reference voltage is subjected to output voltage range verification and ripple suppression processing to obtain the corrected reference voltage.

8. The integrated system for acquiring battery module voltage and temperature based on die-cut FDC as described in claim 7, characterized in that, The process of superimposing the reverse compensation voltage component onto the reference output terminal of the reference voltage source to obtain the initial value of the compensated reference voltage specifically includes: The polarity matching verification of the reverse compensation voltage component is consistent with the temperature drift direction of the reference voltage source, and the real-time reference voltage amplitude of the reference output terminal is extracted to obtain the reference component to be superimposed. The reverse compensation voltage component and the reference component to be superimposed are differentially superimposed under common-mode suppression, and the superposition result is subjected to transient overshoot blanking to obtain the initial value of the compensated reference voltage.

9. The integrated system for acquiring battery module voltage and temperature based on die-cut FDC as described in claim 1, characterized in that, Disconnecting the constant current and connecting the positive electrode temperature sensing line and the negative electrode sampling line to the high-impedance sampling terminal of the voltage acquisition unit specifically includes: A shutdown control command is applied to the constant current, and residual excitation discharge and potential stability detection are performed on the die-cut temperature sensing section to obtain an excitation shutdown confirmation state. In the excitation off confirmation state, the positive electrode temperature sensing line and the negative electrode sampling line are cut out from the excitation circuit and connected to the high-impedance sampling terminal of the voltage acquisition unit to form a high-impedance isolated sampling path.

10. The integrated system for acquiring battery module voltage and temperature based on die-cut FDC as described in claim 1, characterized in that, Based on the corrected reference voltage, the differential voltage response between the positive electrode temperature sensing line and the negative electrode sampling line is extracted, and the cell voltage is determined specifically, including: The corrected reference voltage is sampled and synchronized with the timing and dynamically biased to obtain a sampling reference level that matches the high-impedance sampling terminal. Under the constraint of the sampling reference level, common-mode interference cancellation and temperature drift residual elimination are performed on the differential signal between the positive electrode temperature sensing line and the negative electrode sampling line to obtain the differential voltage response; The differential voltage response is subjected to full-scale verification and linearity correction, and the corrected differential voltage response is mapped to the cell terminal voltage range to determine the cell voltage.

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