Detection circuit, early warning method, early warning device, computer device and electronic equipment

Abstract

The invention discloses a detection circuit of an internal short circuit resistor of a battery, a short circuit early warning method of the battery, an early warning device of the battery, a computer device, electronic equipment, a computer readable storage medium and a computer program product. The detection circuit comprises a first detection resistor and a second detection resistor. The first detection resistor is connected between the positive electrode and the negative electrode of the battery. The second detection resistor is connected to the positive electrode of the battery and the detection point of the battery loop, the first load resistor exists between the positive electrode of the battery and the detection point, and the second load resistor exists between the negative electrode of the battery and the detection point. According to the detection circuit for the internal short-circuit resistance of the battery, the internal short-circuit resistance of the battery can be directly detected, so that the internal short-circuit state of the battery can be reflected, and the performance of the battery can be improved according to the internal short-circuit state of the battery.

Description

Technical Field

[0001] The present application relates to the technical field of short circuit warning, and more specifically, to a detection circuit for internal short circuit resistance of a battery, a short circuit warning method for a battery, a warning device for a battery, a computer device, an electronic device, a computer-readable storage medium, and a computer program product. Background Art

[0002] The internal short circuit state of the battery will affect whether the battery can work normally, or whether it is about to fail or even a safety accident. For example, a battery short circuit will cause the battery temperature to rise too high, smoke, catch fire, and explode. Therefore, detecting the internal short circuit state of the battery can improve the performance of the battery and ensure the safe and normal operation of the battery. The internal short circuit state of the battery can be evaluated by detecting the internal short circuit resistance of the battery. However, since the internal short circuit resistance of the battery is located inside the battery and mixed with the internal resistance of the battery, the internal short circuit resistance is difficult to measure directly. In this way, it is impossible to evaluate the internal short circuit state of the battery, and therefore it is impossible to improve the performance of the battery accordingly. Summary of the invention

[0003] Embodiments of the present application provide a detection circuit for the internal short-circuit resistance of a battery, a battery short-circuit warning method, a battery warning device, a computer device, an electronic device, a computer-readable storage medium, and a computer program product.

[0004] The detection circuit of the internal short-circuit resistance of the battery provided in the embodiment of the present application includes a first detection resistor and a second detection resistor. The first detection resistor is connected between the positive electrode and the negative electrode of the battery. The second detection resistor is connected to the positive electrode of the battery and the detection point of the battery circuit, and there is a first load resistor between the positive electrode of the battery and the detection point, and there is a second load resistor between the negative electrode of the battery and the detection point.

[0005] The detection circuit of the internal short-circuit resistance of the battery provided in the embodiment of the present application can directly detect the internal short-circuit resistance of the battery to reflect the internal short-circuit state of the battery, and is also conducive to improving the performance of the battery according to the internal short-circuit state of the battery.

[0006] In some embodiments, the battery includes an equivalent electromotive force and an equivalent internal resistance, the negative electrode of the equivalent electromotive force is connected to the negative electrode of the battery through the equivalent internal resistance, the positive electrode of the equivalent electromotive force is connected to the positive electrode of the battery, and the internal short circuit resistance of the battery includes an internal short circuit area resistance and a non-internal short circuit area resistance, the non-internal short circuit area resistance is the resistance between the negative electrode of the equivalent electromotive force and the negative electrode of the battery, and the internal short circuit area resistance is the resistance between the positive electrode of the battery and the negative electrode of the battery. The detection circuit also includes a detection module and a calculation module, the detection module is configured to detect the first load resistance and the second load resistance, and the calculation module is configured to calculate and determine the internal short circuit area resistance and the non-internal short circuit area resistance according to the first load resistance, the second load resistance, the first detection resistance and the second detection resistance.

[0007] The short circuit warning method of a battery provided in an embodiment of the present application includes: calculating and determining the internal short circuit area resistance of the battery according to the first load resistance, the second load resistance, the first detection resistance and the second detection resistance; and performing a short circuit warning according to the internal short circuit area resistance of the battery.

[0008] In certain embodiments, the short circuit warning based on the internal short circuit area resistance of the battery includes: obtaining multiple resistance characteristic curves when the battery has an internal short circuit under different operating conditions, each resistance characteristic curve corresponding to one operating condition; comparing the internal short circuit area resistance of the battery with the characteristic value corresponding to each resistance characteristic curve to determine the internal short circuit operating condition of the battery; and providing a short circuit warning based on the internal short circuit operating condition of the battery.

[0009] In certain embodiments, the internal short circuit area resistance of the battery is compared with the characteristic value corresponding to each of the resistance characteristic curves to determine the internal short circuit condition of the battery, including: when the internal short circuit area resistance of the battery is greater than the characteristic value corresponding to each of the resistance characteristic curves, determining that the battery has no internal short circuit; when the internal short circuit area resistance of the battery is less than the characteristic value corresponding to any one of the resistance characteristic curves, determining that the battery has an internal short circuit.

[0010] In some embodiments, the characteristic values ​​corresponding to the resistance characteristic curve include a first characteristic value, a second characteristic value, and a third characteristic value, and when the internal short circuit area resistance of the battery is less than the characteristic value corresponding to any one of the resistance characteristic curves, determining that the battery has an internal short circuit includes: when the internal short circuit area resistance is less than the first characteristic value and greater than the second characteristic value, determining that the battery has a first type of internal short circuit; when the internal short circuit area resistance is less than the second characteristic value and greater than the third characteristic value, determining that the battery has a second type of internal short circuit; when the internal short circuit area resistance is less than the third characteristic value, determining that the battery has a third type of internal short circuit. The short circuit warning according to the internal short circuit working condition of the battery includes: when the first type of internal short circuit occurs in the battery, an internal short circuit prompt is issued, the current flowing through the battery is reduced to a first preset current, and the sampling frequency of the internal short circuit area resistance is increased; when the second type of internal short circuit occurs in the battery, an internal short circuit prompt is issued, the current flowing through the battery is reduced to a second preset current, and the sampling frequency of the internal short circuit area resistance is increased, and the second preset current value is less than the first preset current; when the third type of internal short circuit occurs in the battery, an internal short circuit prompt is issued, the battery is controlled to stop working, and the sampling frequency of the internal short circuit area resistance is increased.

[0011] In certain embodiments, the internal short circuit area resistance of the battery is compared with the characteristic value corresponding to each of the resistance characteristic curves to determine the internal short circuit condition of the battery, including: when it is determined that the battery has an internal short circuit, obtaining the temperature value of the battery and calibrating it to an initial temperature value; calibrating the characteristic value closest to the internal short circuit area resistance as a simulated characteristic value, and the resistance characteristic curve corresponding to the simulated characteristic value as a simulated characteristic curve; determining the temperature change rate of the battery according to the simulated characteristic curve and a non-steady-state heat transfer equation; determining the temperature of the battery at different times according to the temperature change rate of the battery and the initial temperature value; and issuing a short circuit warning according to the internal short circuit situation of the battery, including: issuing a temperature warning according to the temperature change rate of the battery and the temperature of the battery at the current moment.

[0012] In certain embodiments, determining the temperature change rate of the battery according to the simulation characteristic curve and the non-steady-state heat transfer equation includes: determining the volume of the internal short-circuit region of the battery according to the simulation characteristic curve; determining the heat generation power according to the voltage of the battery and the volume of the internal short-circuit region; determining the temperature change rate of the battery according to the heat generation power, the core specific heat capacity of the battery, the core density and the core thermal conductivity.

[0013] In certain embodiments, the temperature warning is performed based on the temperature change rate of the battery and the current temperature of the battery, including: when the current temperature of the battery is greater than a preset temperature, or the temperature change rate of the battery is greater than a first preset temperature change rate, an over-temperature prompt is issued, the current flowing through the battery is reduced to a third preset current, and the power of the heat dissipation device of the battery is increased; when the current temperature of the battery is greater than the preset temperature, and the temperature change rate of the battery is greater than a second preset temperature change rate, an over-temperature prompt is issued, and the battery is controlled to stop working.

[0014] The early warning device of the battery provided in the embodiment of the present application includes a measurement module, a calculation module and an early warning module. The measurement module is configured to detect the first load resistance, the second load resistance, the first detection resistance and the second detection resistance. The calculation module is configured to calculate and determine the internal short circuit area resistance and the non-internal short circuit area resistance of the battery according to the first load resistance, the second load resistance, the first detection resistance and the second detection resistance. The early warning module is configured to perform a short circuit early warning according to the internal short circuit area resistance.

[0015] The computer device provided in the embodiment of the present application includes a memory and a processor, the memory is configured to store a computer program, and the processor implements the above-mentioned battery short circuit warning method when executing the computer program.

[0016] The electronic device provided in the embodiments of the present application includes a battery and an early warning device or a computer device of the battery provided in the embodiments of the present application.

[0017] The computer-readable storage medium provided in the embodiments of the present application stores a computer program / instruction. When the computer program is executed by one or more processors, the short-circuit warning method for a battery provided in the embodiments of the present application is implemented.

[0018] The computer program product provided in the embodiments of the present application includes a computer program / instruction, and when the computer program / instruction is executed by a processor, the short circuit warning method of the battery provided in the embodiments of the present application is implemented.

[0019] The detection circuit of the internal short-circuit resistance of the battery provided in the embodiment of the present application includes a first detection resistor and a second detection resistor. The first detection resistor is connected between the positive electrode and the negative electrode of the battery. The second detection resistor is connected to the positive electrode of the battery and the detection point of the battery circuit, and there is a first load resistor between the positive electrode of the battery and the detection point, and there is a second load resistor between the negative electrode of the battery and the detection point.

[0020] The detection circuit of the internal short-circuit resistance of the battery provided in the embodiment of the present application can directly detect the internal short-circuit resistance of the battery to reflect the internal short-circuit state of the battery, and is also conducive to improving the performance of the battery according to the internal short-circuit state of the battery.

[0021] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0023] Figure 1 is a schematic diagram of a detection circuit provided in certain embodiments of the present application;

[0024] Figure 2 is a schematic diagram of a short circuit early warning method provided in certain embodiments of the present application;

[0025] Figure 3 is a schematic diagram of an early warning device provided in certain embodiments of the present application;

[0026] Figure 4 is a schematic diagram of a short circuit early warning method provided in certain embodiments of the present application;

[0027] Figure 5 is a schematic diagram of a characteristic curve provided by certain embodiments of the present application;

[0028] Figure 6 It is a schematic diagram of a short circuit warning method provided by certain embodiments of the present application.

[0029] Description of the drawings: detection circuit 100, battery 10, detection point 11, first load resistor 12, second load resistor 13, first detection resistor 21, second detection resistor 22, detection module 30, calculation module 40, warning device 200, warning module 50. DETAILED DESCRIPTION

[0030] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions from beginning to end. The embodiments described below with reference to the accompanying drawings are optional and are only used to explain the embodiments of the present application, and cannot be understood as limiting the embodiments of the present application.

[0031] The internal short circuit state of the battery will affect whether the battery can work normally, or whether it is about to fail or even a safety accident. For example, a battery short circuit will cause the battery temperature to rise too high, smoke, catch fire, and explode. Therefore, detecting the internal short circuit state of the battery can improve the performance of the battery and ensure the safe and normal operation of the battery. The internal short circuit state of the battery can be evaluated by detecting the internal short circuit resistance of the battery. However, since the internal short circuit resistance of the battery is located inside the battery and mixed with the internal resistance of the battery, the internal short circuit resistance is difficult to measure directly. In this way, it is impossible to evaluate the internal short circuit state of the battery, and therefore it is impossible to improve the performance of the battery accordingly.

[0032] In order to solve the above technical problems, the embodiments of the present application provide a detection circuit for the internal short-circuit resistance of a battery, a battery short-circuit warning method, a battery warning device, a computer device, an electronic device, a computer-readable storage medium and a computer program product.

[0033] The detection circuit 100 of the internal short-circuit resistance of the battery 10, the short-circuit warning method of the battery 10, the warning device 200 of the battery 10, the computer device, the electronic device, the computer-readable storage medium and the computer program product provided in the embodiments of the present application can also be used for single cells, battery 10 modules and battery 10 packs formed by connecting multiple batteries 10 in series or in parallel.

[0034] Reference Figure 1 The detection circuit 100 of the internal short-circuit resistance of the battery 10 provided in the embodiment of the present application includes a first detection resistor 21 and a second detection resistor 22. The first detection resistor 21 is connected between the positive electrode and the negative electrode of the battery 10. The second detection resistor 22 is connected between the positive electrode of the battery 10 and the detection point 11 of the battery 10 circuit, and there is a first load resistor 12 between the positive electrode of the battery 10 and the detection point 11, and there is a second load resistor 13 between the negative electrode of the battery 10 and the detection point 11.

[0035] The internal short-circuit resistance detection circuit 100 of the battery 10 provided in the embodiment of the present application can directly detect the internal short-circuit resistance of the battery 10 so as to reflect the internal short-circuit state of the battery 10 , and is also beneficial to improving the performance of the battery 10 according to the internal short-circuit state of the battery 10 .

[0036] Specifically, the positive electrode of the battery 10 can be connected to the negative electrode of the battery 10 through the battery 10 loop. A corresponding detection point 11 can be set on the battery 10 loop. On the battery 10 loop, the resistance between the detection point 11 and the positive electrode of the battery 10 can be set as the first load resistance 12, and the resistance between the detection point 11 and the negative electrode of the battery 10 can be set as the second load resistance 13. The detection circuit 100 can be connected to the detection point 11 of the battery 10 loop, the positive electrode of the battery 10 and the negative electrode of the battery 10, so that the detection circuit 100 detects the internal short-circuit resistance of the battery 10.

[0037] The detection circuit 100 may include a first detection resistor 21 and a second detection resistor 22. The first detection resistor 21 may be a resistance element R1, and the first detection resistor 21 may be a resistance element R2. The first load resistor 12 between the detection point 11 and the positive electrode of the battery 10 may be a resistance element R1, and the first load resistor 12 between the detection point 11 and the negative electrode of the battery 10 may be a resistance element R2.

[0038] The resistor R1 can be connected between the positive electrode and the negative electrode of the battery 10, the first end of the resistor R2 can be connected to the positive electrode of the battery 10, and the second end of the resistor R2 can be connected to the detection point 11 on the circuit of the battery 10. The second end of the resistor R2 can be connected to the positive electrode of the battery 10 through the resistor R1, and the second end of the resistor R2 can also be connected to the negative electrode of the battery 10 through the resistor R2.

[0039] When the resistance element R1, the resistance element R2, the resistance element R1, and the resistance element R2 are known, the internal short-circuit resistance of the battery 10 can be calculated and determined based on the resistance voltage division formula.

[0040] In some embodiments, the battery 10 includes an equivalent electromotive force and an equivalent internal resistance, the negative electrode of the equivalent electromotive force is connected to the negative electrode of the battery 10 through the equivalent internal resistance, the positive electrode of the equivalent electromotive force is connected to the positive electrode of the battery 10, and the internal short circuit resistance of the battery 10 includes an internal short circuit region resistance and a non-internal short circuit region resistance, the non-internal short circuit region resistance is the resistance between the negative electrode of the equivalent electromotive force and the negative electrode of the battery 10, and the internal short circuit region resistance is the resistance between the positive electrode of the battery 10 and the negative electrode of the battery 10. The detection circuit 100 also includes a detection module 30 and a calculation module 40, the detection module 30 is configured to detect the first load resistor 12 and the second load resistor 13, and the calculation module 40 is configured to calculate and determine the internal short circuit region resistance and the non-internal short circuit region resistance according to the first load resistor 12, the second load resistor 13, the first detection resistor 21, and the second detection resistor 22.

[0041] Specifically, the equivalent circuit in the battery 10 may include an equivalent electromotive force and an equivalent internal resistance, the positive electrode of the equivalent electromotive force may be connected to the positive electrode of the battery 10 , and the negative electrode of the equivalent electromotive force may be connected to the negative electrode of the battery 10 through the equivalent internal resistance.

[0042] The internal short-circuit resistance may include an internal short-circuit region resistance and a non-internal short-circuit region resistance. The non-internal short-circuit region resistance may be x(1), and the internal short-circuit region resistance may be x(2). The positive electrode and the negative electrode of the equivalent electromotive force may be connected through the non-internal short-circuit region resistance and the internal short-circuit region resistance. Among them, the non-internal short-circuit region resistance may be connected in series with the battery 10 circuit, and the internal short-circuit region resistance may be connected in parallel with the battery 10 circuit.

[0043] The detection module 30 can determine the resistance of the resistance element R1 by detecting the resistance between the positive electrode of the battery 10 and the detection point 11, and determine the resistance of the resistance element R2 by detecting the resistance between the negative electrode of the battery 10 and the detection point 11. The resistance element R1 and the resistance element R2 can be set resistances, and the calculation module 40 can calculate and determine the internal short-circuit area resistance and the non-internal short-circuit area resistance according to the first load resistor 12, the second load resistor 13, the first detection resistor 21 and the second detection resistor 22. The calculation formula can refer to:

[0044] 1 / (x(1)*x(2) / (x(1)+x(2)))+1 / (R1+R2)=1 / R1 measurement;

[0045] 1 / (x(1)*x(2) / (x(1)+x(2))+R2)+1 / R1=1 / R2 measurement.

[0046] When the short-circuit resistance in the battery 10 decreases, x(1) and x(2) will decrease. Since the resistance in the non-short-circuit area can be connected in series with the battery 10 circuit, and there are a first load resistor 12 and a second load resistor 13 in the battery 10 circuit, the decrease in x(1) will not cause the current flowing through the equivalent electromotive force to suddenly increase. Since the resistance in the short-circuit area is the resistance between the positive and negative electrodes of the equivalent electromotive force, the decrease in x(2) will cause the current flowing through the equivalent electromotive force to suddenly increase.

[0047] It can be understood that the short circuit in the battery 10 is caused by the decrease of the resistance x(2) in the short circuit region.

[0048] Reference Figure 2 The short circuit warning method of the battery 10 provided in the embodiment of the present application includes:

[0049] Step 01: Calculate and determine the internal short-circuit resistance of the battery 10 according to the first load resistor 12, the second load resistor 13, the first detection resistor 21 and the second detection resistor 22;

[0050] Step 02: Provide a short circuit warning based on the internal short circuit area resistance of the battery 10.

[0051] Specifically, the short circuit warning method of the battery 10 provided in the embodiment of the present application can use the detection circuit 100 provided in the embodiment of the present application to detect and determine the internal short circuit area resistance of the battery 10, and perform a short circuit warning based on the internal short circuit area resistance of the battery 10.

[0052] It is understandable that the detection circuit 100 provided in the embodiment of the present application can directly detect the internal short circuit area resistance of the battery 10, which is conducive to evaluating the short circuit state inside the battery 10 and providing a short circuit warning based on the short circuit state inside the battery 10.

[0053] Reference Figure 3, the early warning device 200 of the battery 10 provided in the embodiment of the present application may include a measurement module, a calculation module 40 and an early warning module 50. Among them, the measurement module is configured to detect the first load resistor 12, the second load resistor 13, the first detection resistor and the second detection resistor. The calculation module 40 is configured to calculate and determine the internal short area resistance and the non-internal short area resistance of the battery 10 according to the first load resistor 12, the second load resistor 13, the first detection resistor 21 and the second detection resistor 22. The early warning module 50 is configured to perform a short circuit early warning according to the internal short area resistance.

[0054] Specifically, there is real-time transmission of data and signals among the measurement module, the calculation module 40 and the early warning module 50 to ensure the accuracy and timeliness of the measurement and early warning.

[0055] The measuring module can measure the resistance change of the first load resistor 12 and the second load resistor 13 in the loop of the battery 10 and the resistance change of the first detection resistor and the second detection resistor and transmit the measured values ​​to the calculation module 40 .

[0056] The calculation module 40 can calculate based on the circuit structure of the detection circuit 100 provided in the embodiment of the present application to obtain the resistance of the non-short circuit area and the resistance of the short circuit area. In order to ensure that R1 and R2 have the least impact on the loop, the first load resistor 12 and the second load resistor 13 are at least at the MΩ level. R1 measurement and R2 measurement are the data of the first detection resistor 21 and the second detection resistor 22 measured by the AC internal resistor, respectively. The measured values ​​are input into the short-circuit internal resistance calculation module 40 of the battery 10, and the sampling frequency of the internal resistor in the measurement module can be adjusted in real time according to actual needs.

[0057] In the calculation module 40, the embedded calculation model is shown in the following equation. By solving the equation, the ohmic impedance x(1) of the non-short circuit area of ​​the short circuit battery 10 and the ohmic resistance x(2) of the short circuit area of ​​the short circuit battery 10 can be obtained, and then the obtained x(2) is input to the early warning module 50.

[0058] 1 / (x(1)*x(2) / (x(1)+x(2)))+1 / (R1+R2)=1 / R1

[0059] 1 / (x(1)*x(2) / (x(1)+x(2))+R2)+1 / R1=1 / R2

[0060] The warning module 50 can perform a short circuit warning according to x(2) input by the calculation module 40 .

[0061] The computer device provided in the embodiment of the present application includes a memory and a processor. The memory is configured to store a computer program. When the processor executes the computer program, the short circuit warning method of the battery 10 provided in the embodiment of the present application is implemented.

[0062] The electronic device provided in the embodiments of the present application includes the early warning device 200 provided in the embodiments of the present application or the computer device provided in the embodiments of the present application.

[0063] The computer-readable storage medium provided in the embodiment of the present application stores a computer program / instruction. When the computer program is executed by one or more processors, the short-circuit warning method of the battery 10 provided in the embodiment of the present application is implemented.

[0064] The computer program product provided in the embodiment of the present application includes a computer program / instruction, and when the computer program / instruction is executed by a processor, the short circuit warning method of the battery 10 provided in the embodiment of the present application is implemented.

[0065] Reference Figure 4 In some embodiments, step 02: performing short circuit warning according to the internal short circuit area resistance of the battery 10 includes:

[0066] Step 021: obtaining multiple resistance characteristic curves when the battery 10 has an internal short circuit under different working conditions, each resistance characteristic curve corresponding to one working condition;

[0067] Step 022: Compare the internal short circuit region resistance of the battery 10 with the characteristic value corresponding to each resistance characteristic curve to determine the internal short circuit condition of the battery 10;

[0068] Step 023: Provide a short circuit warning according to the internal short circuit condition of the battery 10.

[0069] In some embodiments, the early warning module 50 can obtain multiple resistance characteristic curves when the battery 10 has an internal short circuit under different operating conditions, each resistance characteristic curve corresponding to one operating condition; compare the internal short circuit area resistance of the battery 10 with the characteristic value corresponding to each resistance characteristic curve to determine the internal short circuit operating condition of the battery 10; and perform a short circuit early warning based on the internal short circuit operating condition of the battery 10.

[0070] Specifically, in the early warning module 50 , in order to ensure the accuracy and effectiveness of the early warning information, the internal short circuit condition of the battery 10 can be determined by comparing x(2) output by the calculation module 40 with the characteristic value corresponding to the resistance characteristic curve.

[0071] In step 021 , a plurality of resistance characteristic curves of the battery 10 when an internal short circuit occurs under different working conditions are measured through preliminary experiments and built into the early warning module 50 .

[0072] by Figure 5 For example, curve L1, curve L2 and curve L3 are three characteristic curves obtained by experimental measurement when the battery 10 has an internal short circuit under different working conditions. The characteristic curves reflect the changes in the internal short circuit area resistance with the degree of internal short circuit under different working conditions of the battery 10.

[0073] If the curve of the internal short circuit area resistance changing with the degree of internal short circuit is between the characteristic curve L1 and the characteristic curve L2, the internal short circuit of the battery 10 is usually caused by the short circuit of the positive and negative electrode materials due to lithium deposition and other reasons. If the curve of the internal short circuit area resistance changing with the degree of internal short circuit is between the characteristic curve L2 and the characteristic curve L3, the internal short circuit of the battery 10 is usually caused by the repeated growth of lithium dendrites and melting, or the battery 10 collision, foil leakage and other factors causing the short circuit of the positive and negative electrode foils. If the curve of the internal short circuit area resistance changing with the degree of internal short circuit is below the characteristic curve L3, the internal short circuit of the battery 10 is usually caused by the repeated growth of lithium dendrites and melting, or collision and other factors causing the short circuit of the positive and negative electrode foils.

[0074] In step 022, each characteristic curve has a corresponding characteristic value, and the characteristic value may be the internal short-circuit resistance corresponding to the initial progress of the characteristic curve. The internal short-circuit resistance output by the calculation module 40 may be compared with the characteristic value corresponding to each resistance characteristic curve to preliminarily determine the working condition of the battery 10.

[0075] In step 023 , after the operating condition of the battery 10 is preliminarily determined, a targeted short circuit warning may be performed according to the operating condition of the short circuit in the battery 10 .

[0076] In some embodiments, step 022: comparing the internal short circuit region resistance of the battery 10 with the characteristic value corresponding to each resistance characteristic curve to determine the internal short circuit condition of the battery 10, includes:

[0077] When the internal short circuit region resistance of the battery 10 is greater than the characteristic value corresponding to each resistance characteristic curve, it is determined that the battery 10 does not have an internal short circuit;

[0078] When the internal short circuit region resistance of the battery 10 is less than a characteristic value corresponding to any one of the resistance characteristic curves, it is determined that the battery 10 has an internal short circuit.

[0079] Specifically, if the internal short circuit area resistance output by the calculation module 40 is greater than the characteristic value corresponding to each resistance characteristic curve, it can be considered that the internal short circuit area resistance is greater than the internal short circuit area resistance when the battery 10 has an internal short circuit, and it is determined that the battery 10 has no internal short circuit.

[0080] If the internal short circuit region resistance output by the calculation module 40 is smaller than the characteristic value corresponding to any resistance characteristic curve, the internal short circuit region resistance is smaller than the internal short circuit region resistance when the battery 10 has an internal short circuit, and it is determined that the battery 10 has an internal short circuit.

[0081] In some embodiments, the characteristic value corresponding to the resistance characteristic curve includes a first characteristic value, a second characteristic value, and a third characteristic value. When the internal short circuit region resistance of the battery 10 is less than the characteristic value corresponding to any one of the resistance characteristic curves, determining that the battery 10 has an internal short circuit includes:

[0082] When the internal short circuit region resistance is less than the first characteristic value and greater than the second characteristic value, it is determined that the battery 10 has a first type of internal short circuit;

[0083] When the internal short circuit region resistance is less than the second characteristic value and greater than the third characteristic value, it is determined that the second type of internal short circuit occurs in the battery 10;

[0084] When the internal short circuit region resistance is less than the third characteristic value, it is determined that the third type of internal short circuit occurs in the battery 10 .

[0085] Specifically, the first characteristic value may be the inner short region resistance corresponding to the characteristic curve L1 at the initial progress, the second characteristic value may be the inner short region resistance corresponding to the characteristic curve L2 at the initial progress, and the third characteristic value may be the inner short region resistance corresponding to the characteristic curve L3 at the initial progress.

[0086] The internal short circuit region resistance output by the calculation module 40 is compared with the first characteristic value, the second characteristic value, and the third characteristic value. If the internal short circuit region resistance output by the calculation module 40 is less than the first characteristic value and greater than the second characteristic value, it can be considered that the curve of the internal short circuit region resistance varying with the degree of internal short circuit is located between the characteristic curve L1 and the characteristic curve L2, and the battery 10 has a first type of internal short circuit, which may be caused by a short circuit of the positive and negative electrode materials due to lithium deposition or other reasons.

[0087] If the internal short circuit area resistance output by the calculation module 40 is less than the second characteristic value and greater than the third characteristic value, it can be considered that the curve of the internal short circuit area resistance varying with the degree of internal short circuit is located between the characteristic curve L2 and the characteristic curve L3, and the battery 10 has a second type of internal short circuit. The second type of internal short circuit may be caused by the repeated growth of lithium dendrites and the melting, or the short circuit of the positive and negative electrode foils caused by factors such as the collision and leakage of the battery 10.

[0088] If the internal short circuit area resistance output by the calculation module 40 is less than the third characteristic value, it can be considered that the curve of the internal short circuit area resistance changing with the degree of internal short circuit is located below the characteristic curve L3, and the battery 10 has a third type of internal short circuit. The third type of internal short circuit may be a short circuit of the positive and negative electrode foils caused by factors such as repeated growth of lithium dendrites, melting, or collision.

[0089] Step 03: Perform short circuit warning according to the internal short circuit condition of the battery 10, including:

[0090] When the first type of internal short circuit occurs in the battery 10, an internal short circuit prompt is issued, the current flowing through the battery 10 is reduced to a first preset current, and the sampling frequency of the internal short circuit area resistance is increased;

[0091] When the second type of internal short circuit occurs in the battery 10, an internal short circuit prompt is issued, the current flowing through the battery 10 is reduced to a second preset current, and the sampling frequency of the internal short circuit area resistance is increased, and the second preset current value is less than the first preset current;

[0092] When the third type of internal short circuit occurs in the battery 10, an internal short circuit prompt is issued, the battery 10 is controlled to stop working, and the sampling frequency of the internal short circuit area resistance is increased.

[0093] Specifically, when it is determined that an internal short circuit occurs in the battery 10, the warning module 50 can send a warning message of an internal short circuit to the cloud platform, mark the risk battery 10 package and send a warning message to the car owner, while increasing the sampling frequency of the internal short circuit area resistance.

[0094] In the case of a first type of internal short circuit in the battery 10, the current flowing through the battery 10 is reduced to the first preset current to avoid damage caused by the internal short circuit in the battery 10. The second type of internal short circuit is more serious than the first type of internal short circuit. In the case of a first type of internal short circuit in the battery 10, the current flowing through the battery 10 is further reduced to the first preset current to avoid damage caused by the internal short circuit in the battery 10. The third type of internal short circuit is more serious than the second type of internal short circuit. In the case of a third type of internal short circuit in the battery 10, the battery 10 is controlled to stop working to avoid damage caused by the internal short circuit in the battery 10.

[0095] In some embodiments, step 022: comparing the internal short circuit region resistance of the battery 10 with the characteristic value corresponding to each resistance characteristic curve to determine the internal short circuit condition of the battery 10, includes:

[0096] Step 0223: When it is determined that the battery 10 has an internal short circuit, the temperature value of the battery 10 is obtained and calibrated as the initial temperature value;

[0097] Step 0224: calibrate the characteristic value closest to the resistance of the inner short region as the simulation characteristic value, and the resistance characteristic curve corresponding to the simulation characteristic value is the simulation characteristic curve;

[0098] Step 0225: Determine the temperature change rate of the battery 10 according to the simulation characteristic curve and the unsteady heat transfer equation;

[0099] Step 0226: determining the temperature of the battery 10 at different times according to the temperature change rate and the initial temperature value of the battery 10;

[0100] Step 03: issuing a short circuit warning according to the internal short circuit condition of the battery 10, including issuing a temperature warning according to the temperature change rate of the battery 10 and the current temperature of the battery 10.

[0101] Specifically, in step 0223, a collection signal of the temperature sampler at the last moment before the internal short circuit of the battery 10 occurs is obtained and recorded as the initial temperature value T0 of the short circuit position of the battery 10.

[0102] In step 0224, among the multiple characteristic values, the characteristic value closest to the internal short-circuit region resistance output by the calculation module 40 is the simulation characteristic value, and the resistance characteristic curve corresponding to the simulation characteristic value is the simulation characteristic curve. If the internal short-circuit region resistance x(1) output by the calculation module 40 is closest to the first characteristic value, the characteristic curve L1 can be calibrated as the simulation characteristic curve. If the internal short-circuit region resistance x(2) output by the calculation module 40 is closest to the second characteristic value, the characteristic curve L2 can be calibrated as the simulation characteristic curve. If the internal short-circuit region resistance x(2) output by the calculation module 40 is closest to the third characteristic value, the characteristic curve L3 can be calibrated as the simulation characteristic curve.

[0103] In step 0225, the temperature change rate dT / dt of the battery 10 can be determined according to the simulation characteristic curve and the unsteady heat transfer equation.

[0104] In step 0226, the real-time temperature Trealtime=T0+∫dT / dt.

[0105] In step 03 , a temperature warning may be issued based on the temperature of the battery 10 and the temperature change rate to avoid thermal runaway of the battery 10 .

[0106] In some embodiments, step 0225: determining the temperature change rate of the battery 10 according to the simulation characteristic curve and the unsteady heat transfer equation includes:

[0107] Determining the volume of the internal short-circuit region of the battery 10 according to the simulation characteristic curve;

[0108] Determine the heat generation power according to the voltage of the battery 10 and the volume of the internal short-circuit area;

[0109] The temperature change rate of the battery 10 is determined based on the heat generation power, the core specific heat capacity of the battery 10, the core density and the core thermal conductivity.

[0110] Specifically, the R feature / V feature can be determined according to the simulation characteristic curve. If the simulation characteristic curve is L1, the R feature / V feature is the first characteristic value / first characteristic volume. If the simulation characteristic curve is L2, the R feature / V feature is the second characteristic value / second characteristic volume. If the simulation characteristic curve is L3, the R feature / V feature is the third characteristic value / third characteristic volume.

[0111] The volume of the internal short-circuit region of the battery 10 is x(2) / V=Rcharacteristic / Vcharacteristic.

[0112] The volume of the internal short-circuit region determines the heat generation power p=U2 / x(2) / V, where U is the voltage of the battery 10.

[0113] Heat generation power

[0114] Wherein, ρ is the core density of the battery 10, Cp is the core specific heat capacity of the battery 10, λ is the core thermal conductivity of the battery 10, and the following table x, y, z represent each direction, dx, dy, dz represent the differential for each direction. The temperature change rate dT / dt of the battery 10 can be calculated based on the heat generation power p.

[0115] In some embodiments, providing a short circuit warning according to the temperature change rate of the battery 10 and the current temperature of the battery 10 includes:

[0116] When the temperature of the battery 10 at the current moment is greater than the preset temperature, or the temperature change rate of the battery 10 is greater than the first preset temperature change rate, an over-temperature prompt is issued, the current flowing through the battery 10 is reduced to a third preset current, and the power of the heat dissipation device of the battery 10 is increased;

[0117] When the current temperature of the battery 10 is greater than the preset temperature, and the temperature change rate of the battery 10 is greater than the second preset temperature change rate, an over-temperature prompt is issued and the battery 10 is controlled to stop working.

[0118] Specifically, if the current temperature of the battery 10 is lower than the preset temperature, and the temperature change rate of the battery 10 is lower than the first preset temperature change rate, an internal short circuit prompt message is issued.

[0119] If the temperature of the battery 10 at the current moment is greater than the preset temperature, or the temperature change rate of the battery 10 is greater than the first preset temperature change rate, an overtemperature prompt is issued to remind that the temperature of the battery 10 is abnormal. At the same time, the current flowing through the battery 10 is reduced to a third preset current, and the power of the heat dissipation device of the battery 10 is increased to reduce the heat of the battery 10.

[0120] If the current temperature of the battery 10 is greater than the preset temperature, and the temperature change rate of the battery 10 is greater than the second preset temperature change rate, an over-temperature prompt is issued and the battery 10 is controlled to stop working.

[0121] In some embodiments, the first preset temperature change rate is 0.02° C. / min, the second preset temperature change rate is 1° C. / s, and the preset temperature is the maximum temperature specified by the manufacturer of the battery 10 .

[0122] In some embodiments, the battery 10 may be a vehicle's battery 10. If the current temperature of the battery 10 is greater than a preset temperature, and the temperature change rate of the battery 10 is greater than a second preset temperature change rate, a vehicle overtemperature prompt is issued and the vehicle is controlled to stop working.

[0123] In the description of this specification, the descriptions with reference to the terms "certain embodiments", "in an example", "exemplarily", etc., mean that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representations 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 the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0124] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code that includes one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in 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 technicians in the technical field to which the embodiments of the present application belong.

[0125] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are optional and cannot be understood as limitations to the present application. A person skilled in the art can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A detection circuit for internal short-circuit resistance of a battery, characterized in that: The detection circuit comprises: A first detection resistor connected between the positive electrode and the negative electrode of the battery; A second detection resistor is connected to the positive electrode of the battery and a detection point of the battery circuit. A first load resistor exists between the positive electrode of the battery and the detection point, and a second load resistor exists between the negative electrode of the battery and the detection point.

2. The detection circuit according to claim 1, characterized in that: The battery comprises an equivalent electromotive force and an equivalent internal resistance, wherein the negative electrode of the equivalent electromotive force is connected to the negative electrode of the battery through the equivalent internal resistance, and the positive electrode of the equivalent electromotive force is connected to the positive electrode of the battery, and the internal short-circuit resistance of the battery comprises an internal short-circuit region resistance and a non-internal short-circuit region resistance, wherein the non-internal short-circuit region resistance is the resistance between the negative electrode of the equivalent electromotive force and the negative electrode of the battery, and the internal short-circuit region resistance is the resistance between the positive electrode of the battery and the negative electrode of the battery; The detection circuit also includes a detection module and a calculation module. The detection module is configured to detect the first load resistance, the second load resistance, the first detection resistance and the second detection resistance. The calculation module is configured to calculate and determine the internal short area resistance and the non-internal short area resistance based on the first load resistance, the second load resistance, the first detection resistance and the second detection resistance.

3. A battery short circuit warning method, characterized in that: A first detection resistor is connected between the positive electrode and the negative electrode of the battery, a second detection resistor is connected between the positive electrode of the battery and a detection point of the battery circuit, a first load resistor exists between the positive electrode of the battery and the detection point, and a second load resistor exists between the negative electrode of the battery and the detection point. The short circuit early warning method includes: Calculate and determine the internal short-circuit resistance of the battery according to the first load resistance, the second load resistance, the first detection resistance, and the second detection resistance; A short circuit warning is performed based on the internal short circuit area resistance of the battery.

4. The battery short circuit warning method according to claim 3, characterized in that: The short circuit warning is performed according to the internal short circuit area resistance of the battery, including: Acquire multiple resistance characteristic curves when the battery has an internal short circuit under different operating conditions, each resistance characteristic curve corresponding to one operating condition; Comparing the internal short circuit region resistance of the battery with the characteristic value corresponding to each of the resistance characteristic curves to determine the internal short circuit condition of the battery; A short circuit warning is performed according to the internal short circuit condition of the battery.

5. The battery short circuit warning method according to claim 4, characterized in that: The step of comparing the internal short circuit region resistance of the battery with a characteristic value corresponding to each of the resistance characteristic curves to determine the internal short circuit condition of the battery includes: When the internal short circuit region resistance of the battery is greater than the characteristic value corresponding to each of the resistance characteristic curves, determining that the battery has no internal short circuit; When the internal short circuit region resistance of the battery is less than a characteristic value corresponding to any one of the resistance characteristic curves, it is determined that the battery has an internal short circuit.

6. The battery short circuit warning method according to claim 5, characterized in that: The characteristic values ​​corresponding to the resistance characteristic curve include a first characteristic value, a second characteristic value, and a third characteristic value, and when the internal short circuit region resistance of the battery is less than the characteristic value corresponding to any one of the resistance characteristic curves, determining that the battery has an internal short circuit includes: When the internal short circuit region resistance is less than the first characteristic value and greater than the second characteristic value, it is determined that the battery has a first type of internal short circuit; When the internal short circuit region resistance is less than the second characteristic value and greater than the third characteristic value, it is determined that the battery has a second type of internal short circuit; When the internal short circuit region resistance is less than the third characteristic value, determining that a third type of internal short circuit occurs in the battery; The short circuit warning is performed according to the internal short circuit condition of the battery, comprising: When the first type of internal short circuit occurs in the battery, an internal short circuit prompt is issued, the current flowing through the battery is reduced to a first preset current, and the sampling frequency of the resistance in the internal short circuit area is increased; When the second type of internal short circuit occurs in the battery, an internal short circuit prompt is issued, the current flowing through the battery is reduced to a second preset current, and the sampling frequency of the internal short circuit area resistance is increased, and the second preset current value is less than the first preset current; When the third type of internal short circuit occurs in the battery, an internal short circuit prompt is issued, the battery is controlled to stop working, and the sampling frequency of the resistance in the internal short circuit area is increased.

7. The battery short circuit warning method according to claim 4, characterized in that: The step of comparing the internal short circuit region resistance of the battery with a characteristic value corresponding to each of the resistance characteristic curves to determine the internal short circuit condition of the battery includes: When it is determined that the battery has an internal short circuit, obtaining a temperature value of the battery and calibrating it as an initial temperature value; The characteristic value closest to the internal short-circuit region resistance is calibrated as a simulation characteristic value, and the resistance characteristic curve corresponding to the simulation characteristic value is a simulation characteristic curve; Determining the temperature change rate of the battery according to the simulation characteristic curve and the unsteady-state heat transfer equation; Determining the temperature of the battery at different times according to the temperature change rate of the battery and the initial temperature value; The providing a short circuit warning according to the internal short circuit condition of the battery includes: providing a temperature warning according to the temperature change rate of the battery and the current temperature of the battery.

8. The battery short circuit warning method according to claim 7, characterized in that: The determining the temperature change rate of the battery according to the simulation characteristic curve and the unsteady heat transfer equation includes: Determining the volume of the internal short-circuit region of the battery according to the simulation characteristic curve; determining heat generation power according to the voltage of the battery and the volume of the internal short-circuit region; The temperature change rate of the battery is determined according to the heat generation power, the core specific heat capacity of the battery, the core density and the core thermal conductivity.

9. The battery short circuit warning method according to claim 6, characterized in that: The performing of temperature warning according to the temperature change rate of the battery and the current temperature of the battery includes: When the temperature of the battery at the current moment is greater than the preset temperature, or the temperature change rate of the battery is greater than the first preset temperature change rate, an over-temperature prompt is issued, the current flowing through the battery is reduced to a third preset current, and the power of the heat dissipation device of the battery is increased; When the temperature of the battery at the current moment is greater than the preset temperature, and the temperature change rate of the battery is greater than the second preset temperature change rate, an over-temperature prompt is issued and the battery is controlled to stop working.

10. A battery early warning device, wherein a first detection resistor is connected between the positive electrode and the negative electrode of the battery, a second detection resistor is connected between the positive electrode of the battery and a detection point of the battery circuit, a first load resistor is present between the positive electrode of the battery and the detection point, and a second load resistor is present between the negative electrode of the battery and the detection point, characterized in that: The early warning device comprises: a measuring module, configured to detect the first load resistor, the second load resistor, the first detection resistor, and the second detection resistor; a calculation module, configured to calculate and determine the internal short-circuit region resistance and the non-internal short-circuit region resistance of the battery according to the first load resistance, the second load resistance, the first detection resistance, and the second detection resistance; The early warning module is configured to provide a short circuit early warning according to the internal short circuit area resistance.

11. A computer device, characterized in that: The computer device includes a memory and a processor, the memory is configured to store a computer program, and the processor implements the short circuit warning method of the battery according to any one of claims 3 to 9 when executing the computer program.

12. An electronic device, characterized in that: The electronic device comprises: Battery; The battery warning device of claim 9 or the computer device of claim 10.

13. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by one or more processors, the short-circuit warning method for a battery according to any one of claims 3 to 9 is implemented.

14. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instructions are executed by a processor, the short circuit warning method for a battery as described in any one of claims 3 to 9 is implemented.

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