A method and device for predicting the life of a battery pack copper busbar

Abstract

The present invention proposes a method and device for predicting the life of a battery pack copper busbar, the method comprising obtaining historical data of a battery pack copper busbar of a set model, the historical data including a stable temperature rise during normal operation, a transient temperature rise during a short circuit, and a corresponding temperature rise threshold; obtaining a target copper busbar failure internal resistance when the copper busbar fails based on the historical data; for the copper busbar to be tested of the same model, testing is performed with operating time and number of short circuits as single variables in different groups to obtain test data, the test data including a rate of change of copper busbar resistance corresponding to multiple operating times and multiple number of short circuits; calculating the remaining life of the copper busbar for different number of short circuits under different operating times based on a copper busbar life calculation formula, the target copper busbar failure internal resistance, and the test data, thereby obtaining a time-number-life correlation relationship for the model; monitoring the actual operating time and actual number of short circuits of the copper busbar during actual operation, retrieving the time-number-life correlation relationship for the same model, thereby obtaining the actual remaining life of the copper busbar.

Description

Technical Field

[0001] The present invention relates to the technical field of battery pack copper bar life prediction, and in particular to a battery pack copper bar life prediction method and device. Background Art

[0002] The copper busbar is a conductive element within the battery pack. Its primary function is to connect the cells in series and parallel, allowing them to output electrical energy. The health of the busbar directly impacts the efficiency and safety of the battery.

[0003] The health of a battery pack's copper busbars includes determining their lifespan. Existing technology primarily determines the lifespan of a copper busbar based on its temperature rise. When the temperature rise exceeds a specified limit, the busbar is considered failed, meaning its remaining lifespan is zero. This testing method typically involves constructing a temperature rise test bench and applying a long-term current to the busbar to measure the temperature rise at different locations. However, this temperature rise test can only determine whether the busbar has failed in its current state; it cannot accurately determine the remaining lifespan of the busbar if it is still functional. Summary of the Invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0005] To this end, the first purpose of the present invention is to propose a method for predicting the life of a battery pack copper busbar to solve the current problem that the life of the copper busbar cannot be quantitatively predicted.

[0006] The second object of the present invention is to provide a device for predicting the life of a battery pack copper bar.

[0007] A third object of the present invention is to provide an electronic device.

[0008] A fourth object of the present invention is to provide a computer-readable storage medium.

[0009] To achieve the above objectives, the first aspect of the present invention provides a method for predicting the life of a battery pack copper bar, comprising:

[0010] Obtain historical data on the copper busbars of a battery pack of a specified model, including the stable temperature rise during normal operation, the transient temperature rise during a short circuit, and the corresponding temperature rise thresholds;

[0011] Obtaining a target copper busbar failure internal resistance when the copper busbar fails based on the historical data;

[0012] For the copper busbars of the same model of battery pack to be tested, two sets of tests were conducted with operating time and number of short circuits as different groups of single variables to obtain test data. The test data included the rate of change of the copper busbar resistance corresponding to multiple operating times and multiple short circuit times.

[0013] Based on the copper busbar life calculation formula, the target copper busbar failure internal resistance and the test data, the remaining life of the copper busbar when different short circuit times occur at different operating times is calculated, thereby obtaining the time-number-life correlation relationship of the model;

[0014] During actual operation, the actual operating time and actual number of short circuits of the copper busbar are monitored, and the time-number-life correlation of the same model is retrieved to obtain the actual remaining life of the copper busbar.

[0015] In the method of the first aspect of the present invention, obtaining the target copper busbar failure internal resistance when the copper busbar fails based on the historical data includes: during normal operation, obtaining a target stable temperature rise greater than a stable temperature rise threshold, and calculating the first copper busbar failure internal resistance under the target stable temperature rise according to the thermal balance principle; when a short circuit occurs, obtaining a target transient temperature rise greater than a transient temperature rise threshold, and calculating the second copper busbar failure internal resistance under the target transient temperature rise according to the energy conservation principle; and selecting the minimum value of the first copper busbar failure internal resistance and the second copper busbar failure internal resistance as the target copper busbar failure internal resistance.

[0016] In the method of the first aspect of the present invention, two groups of tests are performed with the operating time and the number of short-circuit times as single variables in different groups to obtain test data, including: performing a first group of tests with the operating time as the single variable, during the first group of tests, measuring the internal resistance of the copper busbar corresponding to different operating times at a set ambient temperature, and then combining the initial copper busbar internal resistance to obtain the first copper busbar resistance value change rate under different operating times; performing a second group of tests with the number of short-circuit times as the single variable, during the second group of tests, measuring the internal resistance of the copper busbar corresponding to different short-circuit times, and then combining the initial copper busbar internal resistance to obtain the second copper busbar resistance value change rate under different short-circuit times.

[0017] In the method of the first aspect of the present invention, the set ambient temperature is updated based on the preset ambient temperature set, so that a first group of tests are performed respectively at different set ambient temperatures, thereby obtaining the time-number-life correlation relationship of the model at different set ambient temperatures.

[0018] In the method of the first aspect of the present invention, during actual operation, the actual ambient temperature is also monitored, and the time-number-life correlation relationship of the same model at the same ambient temperature is retrieved to obtain the actual remaining life of the copper busbar.

[0019] In the method of the first aspect of the present invention, the copper busbar life calculation formula satisfies:

[0020] t 寿 =(Rm-R0-ρ2*n) / ρ1

[0021] Where Rm is the target copper bar failure internal resistance, R0 is the initial copper bar internal resistance, n is the number of short circuits, ρ1 is the change rate of the first copper bar resistance, ρ2 is the change rate of the second copper bar resistance, t 寿 The remaining life of the copper busbar.

[0022] To achieve the above-mentioned purpose, the second aspect of the present invention provides a battery pack copper bar life prediction device, comprising:

[0023] A failure internal resistance calculation module is used to obtain historical data on the copper busbars of a battery pack of a set model, including the stable temperature rise during normal operation, the transient temperature rise during a short circuit, and the corresponding temperature rise thresholds; and to obtain the target copper busbar failure internal resistance when the copper busbar fails based on the historical data;

[0024] A test module is used to perform two sets of tests on the copper busbars of the same model of battery pack to be tested, using operating time and number of short circuits as different groups of single variables to obtain test data. The test data includes the rate of change of the copper busbar resistance corresponding to multiple operating times and multiple short circuit times;

[0025] A correlation module is used to calculate the remaining life of the copper busbar when different short circuit times occur under different operating times based on the copper busbar life calculation formula, the target copper busbar failure internal resistance and the test data, so as to obtain the time-number-life correlation relationship of the model;

[0026] The prediction module is used to monitor the actual operating time and actual short-circuit times of the copper busbar during actual operation, and retrieve the time-number-life correlation of the same model to obtain the actual remaining life of the copper busbar.

[0027] In the device of the second aspect of the present invention, in the association module, the copper busbar life calculation formula satisfies:

[0028] t 寿 =(Rm-R0-ρ2*n) / ρ1

[0029] Where Rm is the target copper bar failure internal resistance, R0 is the initial copper bar internal resistance, n is the number of short circuits, ρ1 is the change rate of the first copper bar resistance, ρ2 is the change rate of the second copper bar resistance, t 寿 The remaining life of the copper busbar.

[0030] To achieve the above-mentioned purpose, the third aspect of the present invention proposes an electronic device, comprising: a processor, and a memory communicatively connected to the processor; the memory stores computer-executable instructions; the processor executes the computer-executable instructions stored in the memory to implement the method proposed in the first aspect of the present invention.

[0031] To achieve the above-mentioned purpose, the fourth aspect of the present invention proposes a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the method proposed in the first aspect of the present invention.

[0032] The present invention provides a method, device, electronic device and storage medium for predicting the life of a battery pack copper busbar. The method obtains historical data of a battery pack copper busbar of a set model, where the historical data includes a stable temperature rise during normal operation, a transient temperature rise during a short circuit and a corresponding temperature rise threshold. The method obtains a target copper busbar failure internal resistance when the copper busbar fails based on the historical data. For the copper busbar of the same model to be tested, two groups of tests are performed with the operating time and the number of short circuits as single variables in different groups to obtain test data. The test data includes the rate of change of the copper busbar resistance corresponding to multiple operating times and multiple short circuit times. The method calculates the remaining life of the copper busbar when different short circuit times occur at different operating times based on the copper busbar life calculation formula, the target copper busbar failure internal resistance and the test data, thereby obtaining a time-time-time-life correlation relationship for the model. During actual operation, the actual operating time and the actual number of short circuits of the copper busbar are monitored, and the time-time-time-life correlation relationship for the same model is retrieved to obtain the actual remaining life of the copper busbar. In this case, the target copper busbar failure internal resistance when the copper busbar fails is calculated, and the test is used to obtain the copper busbar resistance value change rate corresponding to multiple operating times and multiple short-circuit times. Then, the copper busbar life calculation formula is used to obtain the copper busbar remaining life when different short-circuit times occur at different operating times, thereby obtaining the time-time-life correlation relationship of this model. In this way, the actual operating time and actual short-circuit times of the copper busbar are monitored during actual operation, and the time-time-life correlation relationship of the same model is retrieved to obtain the accurate actual remaining life of the copper busbar, thereby solving the current problem of not being able to quantitatively predict the copper busbar life.

[0033] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0035] Figure 1 A schematic flow chart of a method for predicting the life of a battery pack copper bar provided by an embodiment of the present invention;

[0036] Figure 2 A schematic diagram of part of the specific process of predicting the life of a battery pack copper bar provided by an embodiment of the present invention;

[0037] Figure 3 Schematic diagram of a copper busbar testing device provided in an embodiment of the present invention;

[0038] Figure 4 This is a block diagram of a battery pack copper bar life prediction device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0039] The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0040] The following describes a method and device for predicting the life of a battery pack copper bar according to an embodiment of the present invention with reference to the accompanying drawings.

[0041] The embodiments of the present invention provide a method for predicting the life of a copper busbar of a battery pack, so as to solve the current problem that the life of the copper busbar cannot be quantitatively predicted.

[0042] Figure 1 A schematic flow chart of a method for predicting the life of a battery pack copper bar provided in an embodiment of the present invention. Figure 2 This is a partial specific flow chart of the battery pack copper bar life prediction process provided by an embodiment of the present invention.

[0043] like Figure 1 As shown, the battery pack copper busbar life prediction method includes the following steps:

[0044] Step S101, obtaining historical data of the copper busbar of a battery pack of a set model, the historical data including the stable temperature rise during normal operation, the transient temperature rise when a short circuit occurs, and the corresponding temperature rise threshold.

[0045] In step S101, historical data for each type of battery pack copper busbar is obtained. This historical data includes the stable temperature rise during normal operation, the transient temperature rise during a short circuit, and the corresponding temperature rise thresholds. The stable temperature rise during normal operation and the transient temperature rise during a short circuit can be collected or calculated.

[0046] In step S101, the temperature rise threshold corresponding to the stable temperature rise is the stable temperature rise threshold, and the temperature rise threshold corresponding to the transient temperature rise is the transient temperature rise threshold.

[0047] Step S102: obtaining a target copper bus failure internal resistance when the copper bus fails based on historical data.

[0048] In step S102, a target copper busbar failure internal resistance is obtained based on historical data when the copper busbar fails, including: during normal operation, obtaining a target stable temperature rise greater than a stable temperature rise threshold, and calculating the first copper busbar failure internal resistance at the target stable temperature rise according to the thermal balance principle; when a short circuit occurs, obtaining a target transient temperature rise greater than a transient temperature rise threshold, and calculating the second copper busbar failure internal resistance at the target transient temperature rise according to the energy conservation principle; and selecting the minimum value of the first copper busbar failure internal resistance and the second copper busbar failure internal resistance as the target copper busbar failure internal resistance.

[0049] For example, considering that the operating temperature of lithium batteries during charge and discharge is ≤55°C and the ambient temperature is generally 25°C, the stable temperature rise threshold is, for example, 30°C. Considering that a sudden high current will cause the copper busbar temperature to rise rapidly, reaching the copper busbar's tolerance temperature, copper will undergo severe oxidation and its mechanical properties will significantly degrade after exceeding the ambient temperature of 300°C and aluminum will exceed the ambient temperature of 200°C. Therefore, the transient temperature rise threshold is, for example, 300°C. Stable temperature rises greater than the stable temperature rise threshold and transient temperature rises greater than the transient temperature rise threshold are screened from historical data. Considering that a stable temperature rise greater than the stable temperature rise threshold or a transient temperature rise greater than the transient temperature rise threshold (i.e., either of the two conditions is met) indicates copper busbar failure, the minimum stable temperature rise greater than the stable temperature rise threshold is selected as the target stable temperature rise ΔT1, and the minimum transient temperature rise greater than the transient temperature rise threshold is selected as the target transient temperature rise ΔT2.

[0050] In step S102, during normal operation, the failure internal resistance of the first copper bar at the target stable temperature rise is calculated according to the principle of thermal balance. In the event of a short circuit, the failure internal resistance of the second copper bar at the target transient temperature rise is calculated according to the principle of energy conservation. The minimum value of the failure internal resistance of the first copper bar and the second copper bar is selected as the target copper bar failure internal resistance (see Figure 2 ).

[0051] Specifically, the calculation process is as follows:

[0052] 21) Considering the conductor heating power P f Satisfy P f =I 2 *R, where I represents the current and R represents the internal resistance of the conductor.

[0053] Under constant current charging and discharging conditions, the change in the internal resistance of the copper busbar directly affects the heating power of the copper busbar.

[0054] 22) Conductor heat dissipation power P s Satisfy P s =K t *A*ΔT, where K t is the comprehensive heat dissipation coefficient, the unit is W / (m 2 *K), the comprehensive heat dissipation coefficient of the vertical copper busbar is generally selected as 6W / (m 2*K)-9W / (m 2 *K), A is the heat dissipation area of ​​the conductor, unit is m 2 . ΔT represents the temperature difference.

[0055] Without changing the placement environment and the heat dissipation area of ​​the copper busbar, the heat dissipation power of the copper busbar is proportional to the temperature difference.

[0056] 23) The change in heat Q of an object m The calculation formula is Q m = C*m*ΔT, where C is the specific heat capacity and ΔT is the temperature difference. m is the mass of the heat-absorbing or heat-releasing substance, in kg.

[0057] 24) The first copper busbar failure internal resistance R1 under the target stable temperature rise ΔT1:

[0058] According to the principle of thermal balance, the heating power P f Equal to the heat dissipation power P s When the conductor reaches thermal stability, the temperature will not rise any further. f =P s =I 2 *R=K t *A*ΔT, where A is the area of ​​the copper busbar, ΔT is ΔT1, and I is the constant current I1 during normal operation of the copper busbar. Therefore, the formula is transformed into: R1=Kt*A*ΔT1 / I12.

[0059] 25) The failure internal resistance R2 of the second copper busbar under the target transient temperature rise ΔT2:

[0060] According to the principle of conservation of energy, the calorific value Q f Equal to the heat dissipation Q s The heat consumed by the object's temperature rising m Among them, the calorific value Q f Equal to the heating power P f The product of heat dissipation Q s Equal to the heat dissipation power P s The product of time. Therefore:

[0061] Q f =Q s +Q m =I 2 *R*t=K t *A*ΔT*t+C*m*ΔT

[0062] Where A is the copper busbar area, ΔT is ΔT², I is the current I² when the copper busbar short-circuits, m is the copper busbar mass, and t is the fuse protection time during a short circuit, generally ≤ 10ms. C is the specific heat capacity of copper, generally 390 J / (kg·°C).

[0063] Therefore, the formula is transformed into: R2=(K t *A*t+C*m)*ΔT2 / (I22*t).

[0064] 26) The target copper busbar failure internal resistance Rm satisfies: Rm = MIN(R1, R2), where MIN() represents the minimum value.

[0065] In step S102, for each set model involved in step S101, the target copper bus failure internal resistance Rm of the corresponding model can be obtained by using the historical data of the corresponding battery pack copper bus and referring to the above calculation process.

[0066] In step S103, two groups of tests are performed on the copper busbars of the same model of the battery pack to be tested, with the operating time and the number of short circuits being different groups of single variables to obtain test data. The test data includes the copper busbar resistance change rate corresponding to multiple operating times and multiple short circuit times.

[0067] In step S103 , for each set model involved in step S101 , the copper busbar of the battery pack to be tested (referred to as the test copper busbar) of each set model is tested using a copper busbar testing device.

[0068] Figure 3 Schematic diagram of the copper busbar testing device provided in an embodiment of the present invention. Figure 3 As shown, the copper busbar testing device includes a high-temperature chamber, a DC current source, a contactor KM, a current sensor TA, a voltmeter PV, and a data acquisition device. The test copper busbar is placed in the high-temperature chamber. The high-temperature chamber controls the ambient temperature of the test copper busbar. The data acquisition device aggregates and records the voltage and current collected by the current sensor TA and voltmeter PV. The DC current source generates current. The contactor KM switches on and off to control current flow, simulating a short circuit.

[0069] In step S103, two groups of tests are performed with the operating time and the number of short-circuit times as single variables in different groups to obtain test data, including: a first group of tests is performed with the operating time as the single variable, during the first group of tests, the internal resistance of the copper busbar corresponding to different operating times is measured at a set ambient temperature, and then combined with the initial copper busbar internal resistance to obtain the first copper busbar resistance value change rate under different operating times; a second group of tests is performed with the number of short-circuit times as the single variable, during the second group of tests, the internal resistance of the copper busbar corresponding to different short-circuit times is measured, and then combined with the initial copper busbar internal resistance to obtain the second copper busbar resistance value change rate under different short-circuit times.

[0070] In some embodiments, the set ambient temperature is updated based on the preset ambient temperature set, so that a first set of tests are performed at different set ambient temperatures, so as to subsequently obtain the time-number-life correlation relationship of the model at different set ambient temperatures.

[0071] Specifically, the process of obtaining the first copper bar resistance value change rate and the second copper bar resistance value change rate (see Figure 2 )as follows:

[0072] 31) Select a copper busbar of a battery pack to be tested, place it in the busbar testing device, and measure the initial internal resistance R0. This resistance is calculated using the voltage U0 measured by the voltmeter PV and the current I0 measured by the current sensor TA at the initial moment. That is, R0 = U0 / I0.

[0073] 32) The ambient temperature of the copper busbar of the battery pack to be tested is maintained at the set ambient temperature by controlling the high-temperature box, and the contactor KM is controlled to remain in the disconnected state to simulate normal operation. The running time is used as a single variable, and the internal resistance Rt1 of the copper busbar corresponding to different running times is measured to obtain the corresponding first copper busbar resistance value change rate ρ1. The calculation formula is as follows:

[0074] ρ1=(Rt1-R0) / Δt=ΔU1 / (I3*Δt)

[0075] Where Rt1 is the internal resistance of the copper busbar corresponding to different operating times, R0 is the initial copper busbar internal resistance, and Δt is the operating time (i.e., the time difference between the current moment and the initial moment). Since the internal resistance cannot be measured directly, it can be calculated indirectly using the voltage collected by the voltmeter PV and the current collected by the current sensor TA. ΔU1 is the voltage difference between the current moment and the initial moment, and I3 is the current collected by the current sensor TA at the current moment. The test was conducted from the initial moment until the copper busbar failed, thereby obtaining the change rate of the first copper busbar resistance value corresponding to multiple operating times at a set ambient temperature.

[0076] Based on the preset ambient temperature set, the set ambient temperature is updated, and the ambient temperature of the copper busbar of the battery pack to be tested is maintained at the new set ambient temperature by controlling the high-temperature box. The above test is repeated to test the first internal resistance change rate at different ambient temperatures, thereby obtaining a first set of test data at different ambient temperatures. The first set of test data includes the corresponding relationship between each operating time and the first internal resistance change rate.

[0077] 32) Control the on and off of the contactor KM to simulate the copper busbar of the battery pack to be tested being subjected to different short-circuit currents (i.e., different short-circuit times). Taking the number of short-circuits as a single variable, measure the internal resistance Rt2 of the copper busbar corresponding to different short-circuit times, and thus obtain the corresponding second copper busbar resistance change rate ρ2. The calculation formula is as follows:

[0078] ρ2=(Rt2-R0) / Δn=ΔU2 / (I4*Δn)

[0079] Where Rt2 is the internal resistance of the copper busbar corresponding to different short-circuit times, and Δn is the number of short-circuits. Since the internal resistance cannot be measured directly, it can be calculated indirectly using the voltage collected by the voltmeter PV and the current collected by the current sensor TA. ΔU2 is the voltage difference from the moment the Δnth short-circuit occurs to the initial moment, and I4 is the current collected by the current sensor TA at the moment the Δnth short-circuit occurs. Testing continues from the initial moment until the copper busbar fails, thereby obtaining the rate of change of the second copper busbar resistance value corresponding to different short-circuit times. Based on a preset set of ambient temperatures, the set ambient temperature is updated, and the above test is repeated to measure the rate of change of the second internal resistance at different ambient temperatures. This results in a second set of test data at different ambient temperatures, which includes the corresponding relationship between the number of short-circuits and the rate of change of the second internal resistance.

[0080] In step S103, for each set model, through the first group of tests and the second group of tests at different ambient temperatures, based on the test data, a set ambient temperature-operating time-first internal resistance change rate association table and a set ambient temperature-number of short circuits-second internal resistance change rate association table of the corresponding model can be formed respectively.

[0081] Step S104 , based on the copper busbar life calculation formula, the target copper busbar failure internal resistance and the test data, the remaining life of the copper busbar when different short circuit times occur at different operating times is calculated, thereby obtaining a time-number-life correlation relationship for the model.

[0082] In step S104, the operating time and the number of short circuits are taken into consideration, and the following copper busbar life calculation formula is constructed when the copper busbar fails:

[0083] t 寿 =(Rm-R0-ρ2*n) / ρ1

[0084] Where Rm is the target copper bar failure internal resistance, R0 is the initial copper bar internal resistance, n is the number of short circuits, ρ1 is the change rate of the first copper bar resistance, ρ2 is the change rate of the second copper bar resistance, t 寿 The remaining life of the copper busbar.

[0085] In step S104, for each set model, a time-number-life association relationship is constructed, which includes the operating time, the number of short circuits, and the remaining life of the copper busbar. The operating time includes all the operating times in the test data, and each operating time is associated with all the short circuit times in the test data. The remaining life of the copper busbar when different short circuit times occur under different operating times is calculated using the copper busbar life calculation formula, combined with the target copper busbar failure internal resistance and the test data (see Figure 2 ).

[0086] Specifically, the target copper bar failure internal resistance of the copper bar of the battery pack of the set model obtained in step S102 and the initial copper bar internal resistance R0 of the corresponding model measured in step S103 are substituted into the copper bar life calculation formula. For each operating time and the corresponding number of short circuits in the time-number-life correlation relationship, the corresponding first copper bar resistance value change rate ρ1 and second copper bar resistance value change rate ρ2 are obtained from the test data obtained in step S103. Then, the first copper bar resistance value change rate ρ1 and the second copper bar resistance value change rate ρ2 and the number of short circuits in the correlation relationship are substituted into the copper bar life calculation formula to calculate the remaining life of the copper bar when different short circuits occur at different operating times.

[0087] In step S104, if the set ambient temperature is taken into account, the time-number-of-life correlation relationship under different set ambient temperatures is obtained. Different set models of battery pack copper bars have corresponding time-number-of-life correlation relationships under different set ambient temperatures.

[0088] Step S105 , during actual operation, monitor the actual operating time and actual short-circuit times of the copper busbar, retrieve the time-time-time-life correlation of the same model, and thus obtain the actual remaining life of the copper busbar.

[0089] In step S105, during actual operation, the actual operating time and actual short circuit times of the copper busbar are monitored, and the time-time-time-life correlation relationship of the same model is retrieved. By finding the same operating time and short circuit times in the time-time-time-life correlation relationship, the actual remaining life of the copper busbar can be obtained.

[0090] In step S105, during actual operation, the actual ambient temperature is also monitored, and the time-frequency life correlation relationship of the same model at the same ambient temperature is retrieved to obtain the actual remaining life of the copper busbar.

[0091] In order to implement the above embodiment, the present invention also proposes a battery pack copper bar life prediction device.

[0092] Figure 4 This is a block diagram of a battery pack copper bar life prediction device provided by an embodiment of the present invention.

[0093] like Figure 4 As shown, the battery pack copper busbar life prediction device includes a failure internal resistance calculation module 11, a test module 12, a correlation module 13, and a prediction module 14, wherein:

[0094] The failure internal resistance calculation module 11 is used to obtain historical data of the copper busbar of a set model battery pack, including the stable temperature rise during normal operation, the transient temperature rise during a short circuit, and the corresponding temperature rise threshold; based on the historical data, the target copper busbar failure internal resistance is obtained when the copper busbar fails;

[0095] Testing module 12 is used to perform two sets of tests on the copper busbars of the same model of battery pack to be tested, using operating time and number of short circuits as different groups of single variables to obtain test data. The test data includes the rate of change of the copper busbar resistance corresponding to multiple operating times and multiple number of short circuits;

[0096] The correlation module 13 is used to calculate the remaining life of the copper busbar when different short circuit times occur under different operating times based on the copper busbar life calculation formula, the target copper busbar failure internal resistance and the test data, so as to obtain the time-number-life correlation relationship of the model;

[0097] The prediction module 14 is used to monitor the actual operating time and actual short circuit times of the copper busbar during actual operation, and retrieve the time-time-time-life correlation relationship of the same model to obtain the actual remaining life of the copper busbar.

[0098] Furthermore, in a possible implementation of an embodiment of the present invention, in the failure internal resistance calculation module 11, a target copper bus failure internal resistance is obtained when the copper bus fails based on historical data, including: during normal operation, a target stable temperature rise greater than a stable temperature rise threshold is obtained, and the failure internal resistance of the first copper bus under the target stable temperature rise is calculated according to the thermal balance principle; when a short circuit occurs, a target transient temperature rise greater than a transient temperature rise threshold is obtained, and the failure internal resistance of the second copper bus under the target transient temperature rise is calculated according to the energy conservation principle; and the minimum value of the first copper bus failure internal resistance and the second copper bus failure internal resistance is selected as the target copper bus failure internal resistance.

[0099] Furthermore, in a possible implementation of an embodiment of the present invention, in the test module 12, two groups of tests are performed with the operating time and the number of short circuits as single variables in different groups to obtain test data, including: a first group of tests are performed with the operating time as the single variable, and during the first group of tests, the internal resistance of the copper busbar corresponding to different operating times is measured at a set ambient temperature, and then combined with the initial copper busbar internal resistance to obtain the first copper busbar resistance value change rate under different operating times; a second group of tests are performed with the number of short circuits as the single variable, and during the second group of tests, the internal resistance of the copper busbar corresponding to different short circuit times is measured, and then combined with the initial copper busbar internal resistance to obtain the second copper busbar resistance value change rate under different short circuit times.

[0100] Furthermore, in a possible implementation of an embodiment of the present invention, in the test module 12, the set ambient temperature is updated based on the preset ambient temperature set, so as to perform a first group of tests at different set ambient temperatures respectively, thereby obtaining the time-number-life correlation relationship of the model at different set ambient temperatures.

[0101] Furthermore, in a possible implementation of the embodiment of the present invention, in the correlation module 13, the copper busbar life calculation formula satisfies:

[0102] t 寿=(Rm-R0-ρ2*n) / ρ1

[0103] Where Rm is the target copper bar failure internal resistance, R0 is the initial copper bar internal resistance, n is the number of short circuits, ρ1 is the change rate of the first copper bar resistance, ρ2 is the change rate of the second copper bar resistance, t 寿 The remaining life of the copper busbar.

[0104] Furthermore, in a possible implementation of the embodiment of the present invention, in the prediction module 14, during actual operation, the actual ambient temperature is also monitored, and the time-number-life correlation relationship of the same model under the same ambient temperature is retrieved to obtain the actual remaining life of the copper busbar.

[0105] It should be noted that the above explanation of the embodiment of the battery pack copper bar life prediction method is also applicable to the battery pack copper bar life prediction device of this embodiment, and will not be repeated here.

[0106] In an embodiment of the present invention, historical data of the copper busbar of a battery pack of a set model is obtained, the historical data including the stable temperature rise during normal operation, the transient temperature rise during a short circuit, and the corresponding temperature rise threshold; the target copper busbar failure internal resistance when the copper busbar fails is obtained based on the historical data; for the copper busbar of the battery pack to be tested of the same model, two groups of tests are performed with the operating time and the number of short circuits as single variables in different groups to obtain test data, the test data including the rate of change of the copper busbar resistance corresponding to multiple operating times and multiple short circuit times; based on the copper busbar life calculation formula, the target copper busbar failure internal resistance and the test data, the remaining life of the copper busbar when different short circuit times occur at different operating times is calculated, thereby obtaining the time-time-life correlation relationship of the model; during actual operation, the actual operating time and the actual number of short circuits of the copper busbar are monitored, and the time-time-life correlation relationship of the same model is retrieved, thereby obtaining the actual remaining life of the copper busbar. In this case, the target copper busbar failure internal resistance when the copper busbar fails is calculated, and the test is used to obtain the copper busbar resistance value change rate corresponding to multiple operating times and multiple short-circuit times. Then, the copper busbar life calculation formula is used to obtain the copper busbar remaining life when different short-circuit times occur at different operating times, thereby obtaining the time-time-life correlation relationship of this model. In this way, the actual operating time and actual short-circuit times of the copper busbar are monitored during actual operation, and the time-time-life correlation relationship of the same model is retrieved to obtain the accurate actual remaining life of the copper busbar. This solves the current problem of not being able to quantitatively predict the copper busbar life, and realizes quantitative prediction of the copper busbar life.

[0107] In the method and system of the present invention, the process of obtaining the time-frequency-life correlation can be regarded as a copper busbar life calculation model. The time-frequency-life correlation obtained through this model is applied to the prediction of the remaining life of the copper busbar in actual operation. Compared with the existing technology, the present invention has the following beneficial effects: 1) a test device is proposed to measure the rate of change of the internal resistance of the copper busbar, which can better characterize the nature of the copper busbar's heating than the existing technology of measuring the temperature rise of the copper busbar; 2) a copper busbar life calculation model is proposed, which can provide early warning; 3) taking into account different environmental temperatures, short-circuit currents and other factors, it is more suitable for the application conditions of the battery pack copper busbar.

[0108] In order to implement the above embodiments, the present invention also proposes an electronic device, comprising: a processor, and a memory communicatively connected to the processor; the memory stores computer-executable instructions; the processor executes the computer-executable instructions stored in the memory to implement the method provided by the above embodiments.

[0109] In order to implement the above embodiments, the present invention further provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the methods provided in the above embodiments.

[0110] In order to implement the above embodiments, the present invention further provides a computer program product, including a computer program, which implements the methods provided in the above embodiments when executed by a processor.

[0111] In the descriptions of the foregoing embodiments, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and features of different embodiments or examples, unless they are mutually inconsistent.

[0112] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0113] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may be performed out of the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present invention pertain.

[0114] The logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing the logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (e.g., a computer-based system, a system including a processor, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device). For purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include the following: an electrical connection with one or more wires (electronic devices), a portable computer disk cartridge (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and programmable read-only memory (EPROM or flash memory), fiber optic devices, and a portable compact disc read-only memory (CDROM). Furthermore, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing it in another suitable manner if necessary, and then storing it in a computer memory.

[0115] It should be understood that various parts of the present invention can be implemented using hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application-specific integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0116] Those skilled in the art will understand that all or part of the steps in the method of the above embodiment can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiment.

[0117] In addition, the functional units in the various embodiments of the present invention may be integrated into a single processing module, or each unit may exist physically separately, or two or more units may be integrated into a single module. The aforementioned integrated modules may be implemented in the form of hardware or in the form of software functional modules. If the integrated modules are implemented in the form of software functional modules and sold or used as independent products, they may also be stored in a computer-readable storage medium.

[0118] The storage medium mentioned above may be a read-only memory, a magnetic disk, or an optical disk, etc. Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and are not to be construed as limiting the present invention. Persons skilled in the art may make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for predicting the life of a battery pack copper bar, characterized in that: include: Obtain historical data on the copper busbars of a battery pack of a specified model, including the stable temperature rise during normal operation, the transient temperature rise during a short circuit, and the corresponding temperature rise thresholds; Obtaining a target copper busbar failure internal resistance when the copper busbar fails based on the historical data, wherein a stable temperature rise greater than a stable temperature rise threshold or a transient temperature rise greater than a transient temperature rise threshold indicates that the copper busbar has failed; For the copper busbars of the same model of battery pack to be tested, two sets of tests were conducted with operating time and number of short circuits as different groups of single variables to obtain test data. The test data included the rate of change of the copper busbar resistance corresponding to multiple operating times and multiple short circuit times. Based on the copper busbar life calculation formula, the target copper busbar failure internal resistance and the test data, the remaining life of the copper busbar when different short circuit times occur at different operating times is calculated, thereby obtaining the time-number-life correlation relationship of the model; During actual operation, the actual operating time and actual short-circuit times of the copper busbar are monitored, and the time-time-time-life correlation relationship of the same model is retrieved to obtain the actual remaining life of the copper busbar; The test data is obtained by performing two sets of tests with the operating time and the number of short circuits as different groups of single variables, including: The first set of tests was conducted using the operating time as the single variable. During the first set of tests, the internal resistance of the copper busbar corresponding to different operating times was measured at a set ambient temperature. Then, combined with the initial copper busbar internal resistance, the rate of change of the first copper busbar resistance under different operating times was obtained. The second set of tests was conducted with the number of short circuits as the single variable. During the second set of tests, the internal resistance of the copper busbar corresponding to different short circuit times was measured, and then the change rate of the second copper busbar resistance under different short circuit times was obtained by combining the initial copper busbar internal resistance. The copper busbar life calculation formula satisfies: t 寿 =(Rm-R0-ρ2*n) / ρ1 Where Rm is the target copper bar failure internal resistance, R0 is the initial copper bar internal resistance, n is the number of short circuits, ρ1 is the change rate of the first copper bar resistance, ρ2 is the change rate of the second copper bar resistance, t 寿 The remaining life of the copper busbar.

2. The method for predicting the life of a battery pack copper bar according to claim 1, characterized in that: The obtaining of a target copper busbar failure internal resistance when the copper busbar fails based on the historical data includes: During normal operation, a target stable temperature rise greater than a stable temperature rise threshold is obtained, and the failure internal resistance of the first copper busbar under the target stable temperature rise is calculated according to the thermal balance principle; When a short circuit occurs, a target transient temperature rise greater than a transient temperature rise threshold is obtained, and the failure internal resistance of the second copper busbar under the target transient temperature rise is calculated according to the principle of conservation of energy; The minimum value of the first copper busbar failure internal resistance and the second copper busbar failure internal resistance is selected as the target copper busbar failure internal resistance.

3. The method for predicting the life of a battery pack copper bar according to claim 1, characterized in that: The set ambient temperature is updated based on the preset ambient temperature set, so as to respectively perform a first group of tests at different set ambient temperatures, thereby obtaining a correlation relationship between the time, number of tests and life of the model at different set ambient temperatures.

4. The method for predicting the life of a battery pack copper bar according to claim 3, characterized in that: During actual operation, the actual ambient temperature is also monitored, and the time-frequency relationship between the same model and the life span at the same ambient temperature is retrieved to obtain the actual remaining life of the copper busbar.

5. A battery pack copper bar life prediction device, characterized in that: include: A failure internal resistance calculation module is configured to obtain historical data on the copper busbars of a battery pack of a specified model, the historical data including the stable temperature rise during normal operation, the transient temperature rise during a short circuit, and the corresponding temperature rise thresholds; and to obtain a target copper busbar failure internal resistance based on the historical data when the copper busbar fails. A stable temperature rise exceeding the stable temperature rise threshold or a transient temperature rise exceeding the transient temperature rise threshold indicates copper busbar failure. A test module is used to perform two sets of tests on the copper busbars of the same model of battery pack to be tested, using operating time and number of short circuits as different groups of single variables to obtain test data. The test data includes the rate of change of the copper busbar resistance corresponding to multiple operating times and multiple short circuit times; A correlation module is used to calculate the remaining life of the copper busbar when different short circuit times occur under different operating times based on the copper busbar life calculation formula, the target copper busbar failure internal resistance and the test data, so as to obtain the time-number-life correlation relationship of the model; The prediction module is used to monitor the actual operating time and actual short-circuit times of the copper busbar during actual operation, and retrieve the time-frequency life correlation of the same model to obtain the actual remaining life of the copper busbar; The testing module is further configured to perform a first set of tests using the operating time as a single variable. During the first set of tests, the internal resistance of the copper busbar corresponding to different operating times is measured at a set ambient temperature, and then, combined with the initial internal resistance of the copper busbar, a rate of change of the first copper busbar resistance under different operating times is obtained. The second set of tests was conducted with the number of short circuits as the single variable. During the second set of tests, the internal resistance of the copper busbar corresponding to different short circuit times was measured, and then the change rate of the second copper busbar resistance under different short circuit times was obtained by combining the initial copper busbar internal resistance. In the associated module, the copper busbar life calculation formula satisfies: t 寿 =(Rm-R0-ρ2*n) / ρ1 Where Rm is the target copper bar failure internal resistance, R0 is the initial copper bar internal resistance, n is the number of short circuits, ρ1 is the change rate of the first copper bar resistance, ρ2 is the change rate of the second copper bar resistance, t 寿 The remaining life of the copper busbar.

6. An electronic device, characterized in that: include: a processor, and a memory communicatively connected to the processor; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory to implement the method according to any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer-executable instructions, which are used to implement the method according to any one of claims 1 to 4 when executed by a processor.

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