Battery current measuring method, battery current measuring circuit and electronic equipment

Abstract

The invention provides a battery current measurement method, a battery current measurement circuit and electronic equipment, and belongs to the technical field of current measurement. The method comprises the following steps: acquiring a terminal voltage difference value of a copper foil at a target detection temperature and a current current value of a control chip; determining compensation impedance corresponding to the control chip according to the terminal voltage difference value, the current current value, the target detection temperature and theoretical copper foil impedance corresponding to the copper foil at the target detection temperature; determining the main loop impedance of the battery current measuring circuit according to the theoretical copper foil impedance and the compensation impedance corresponding to the copper foil at the target detection temperature; and according to the main loop impedance and the terminal voltage difference value, obtaining the measurement current of the battery current measurement circuit at the target detection temperature. The battery current measuring circuit can achieve the effects of measuring the battery current with high precision and reducing the production cost of the battery current measuring circuit.

Description

Technical Field

[0001] The present application relates to the technical field of current measurement, and in particular, to a battery current measurement method, a battery current measurement circuit, and an electronic device. Background Art

[0002] In recent years, with the rapid growth of the national economy, various electronic devices have been put on the market, such as laptop computers, smart TVs, mobile phones, etc. Among them, a large number of electronic devices rely on batteries to provide electrical energy, and the operating state of the battery seriously affects the operating safety and reliability of the electronic device. Therefore, a battery current measurement circuit is usually deployed in the electronic device to measure the operating current of the battery in real time through the battery current measurement circuit, and judge the operating state of the battery and possible fault problems during battery operation based on the operating current of the battery, thereby improving the operating safety and reliability of the electronic device.

[0003] In the related art, a precision resistor component R-sense is usually deployed in the main circuit of the battery current measurement circuit, and the resistance value and terminal voltage difference of the precision resistor component R-sense in the main circuit are measured, and the measured current is calculated based on Ohm's law.

[0004] However, when measuring the battery current based on the related art, there is a disadvantage that the cost of the precision resistor component is relatively high, which in turn increases the production cost of the battery current measurement circuit. Summary of the Invention

[0005] The purpose of the present application is to provide a battery current measurement method, a battery current measurement circuit, and an electronic device, which can achieve the effect of measuring the battery current with high precision and reducing the production cost of the battery current measurement circuit.

[0006] The embodiments of the present application are implemented as follows:

[0007] In the first aspect of the embodiments of the present application, a battery current measurement method is provided. This method is applied to a control chip in a battery current measurement circuit. A copper foil is also provided in the battery current measurement circuit. The control chip is connected to the copper foil, and a preset distance is set between the copper foil and the control chip. The method includes:

[0008] Obtain the terminal voltage difference of the copper foil and the current value of the control chip at the target detection temperature;

[0009] Determine the compensation impedance corresponding to the control chip according to the terminal voltage difference of the copper foil, the current value of the control chip, the target detection temperature, and the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature. The theoretical copper foil impedance is determined based on multiple actual copper foil impedances at each detected temperature obtained;

[0010] Determine the main circuit impedance of the battery current measurement circuit according to the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature and the compensation impedance corresponding to the control chip;

[0011] Obtain the measured current of the battery current measurement circuit at the target detection temperature according to the main circuit impedance and the voltage difference at both ends of the copper foil.

[0012] As a possible implementation, the theoretical copper foil impedance is determined based on multiple actual copper foil impedances at each detected temperature obtained, including:

[0013] According to each detected temperature and the corresponding actual copper foil impedance at each temperature, fit to obtain the temperature-impedance curve corresponding to the battery current measurement circuit;

[0014] According to the corresponding relationship between the detected temperature indicated by the temperature-impedance curve and the main circuit impedance, determine the first impedance factor, the second impedance factor, the third impedance factor, and the fourth impedance factor of the copper foil;

[0015] According to the first impedance factor, the second impedance factor, the third impedance factor, the fourth impedance factor, and each detected temperature, determine the theoretical copper foil impedance corresponding to the copper foil at each detected temperature.

[0016] As a possible implementation, according to the first impedance factor, the second impedance factor, the third impedance factor, the fourth impedance factor, and each detected temperature, determine the theoretical copper foil impedance corresponding to the copper foil at each detected temperature, including:

[0017] Calculate the first product between the first impedance factor and the cube of the detected temperature;

[0018] Calculate the second product between the second impedance factor and the square of the detected temperature;

[0019] Calculate the third product between the third impedance factor and the detected temperature;

[0020] Calculate the sum of the first product, the second product, the third product, and the fourth impedance factor to obtain the theoretical copper foil impedance corresponding to the copper foil at each detected temperature.

[0021] As a possible implementation, according to the voltage difference at both ends of the copper foil, the current value of the control chip at present, the target detection temperature, and the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature, determine the compensation impedance corresponding to the control chip, including:

[0022] According to the voltage difference at both ends of the copper foil and the current value of the control chip at present, determine the actual resistance value of the copper foil at the target detection temperature;

[0023] According to the actual resistance value of the copper foil at the target detection temperature and the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature, determine the compensation impedance corresponding to the control chip.

[0024] As a possible implementation, according to the voltage difference at both ends of the copper foil and the current value of the control chip, determine the actual resistance value of the copper foil at the target detection temperature, including:

[0025] Calculate the first ratio between the voltage difference at both ends of the copper foil and the current value of the control chip;

[0026] According to the first ratio, determine the actual resistance value of the copper foil at the target detection temperature.

[0027] As a possible implementation, according to the actual resistance value of the copper foil at the target detection temperature and the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature, determine the compensation impedance corresponding to the control chip, including:

[0028] Calculate the difference between the actual resistance value of the copper foil at the target detection temperature and the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature;

[0029] According to the difference, determine the compensation impedance corresponding to the control chip.

[0030] As a possible implementation, according to the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature and the compensation impedance corresponding to the control chip, determine the main circuit impedance of the battery current measurement circuit, including:

[0031] Calculate the sum of the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature and the compensation impedance corresponding to the control chip to obtain the main circuit impedance of the battery current measurement circuit.

[0032] As a possible implementation, according to the main circuit impedance and the voltage difference at both ends of the copper foil, obtain the measured current of the battery current measurement circuit at the target detection temperature, including:

[0033] Calculate the second ratio between the voltage difference at both ends of the copper foil and the main circuit impedance to obtain the measured current measured by the battery current measurement circuit at the target detection temperature.

[0034] In the second aspect of the embodiments of the present application, a battery current measurement circuit is provided. The battery current measurement circuit includes: a battery module, a fuse unit, a switch unit, a copper foil, and a control chip;

[0035] The first end of the battery module is respectively connected to the first end of the control chip and the first end of the fuse unit. The second end of the battery module is connected to the second end of the control chip. The third end of the battery module is respectively connected to one end of the copper foil and the first sampling end of the control chip;

[0036] The second end of the fuse unit is connected to the first end of the switch unit. The control end of the fuse unit is connected to the third end of the control chip. The third end of the fuse unit is connected to the copper foil;

[0037] The second end of the switching unit is connected to the positive power supply port, the control end of the switching unit is connected to the fourth end of the control chip, the second sampling end of the control chip is connected to the other end of the copper foil, and the copper foil is also used to connect to the negative power supply port;

[0038] The control chip is used to execute the steps of the battery current measurement method described in the first aspect above.

[0039] In the third aspect of the embodiments of the present application, an electronic device is provided, and the electronic device includes the battery current measurement circuit described in the second aspect above.

[0040] The beneficial effects of the embodiments of the present application include:

[0041] A battery current measurement method provided by the embodiments of the present application, the control chip uses the built-in temperature acquisition device to collect the detection temperature in real time, and at the same time obtains the terminal voltage difference of the copper foil at the current moment under the target detection temperature through the ports connected to both ends of the copper foil by the control chip, and obtains the current current value flowing through the control chip at the current moment through the current acquisition component built in the control chip; according to the terminal voltage difference of the copper foil at the current moment under the target detection temperature, the theoretical copper foil impedance, the current current value of the control chip, and the temperature value indicated by the target detection temperature, calculate the compensation impedance corresponding to the control chip; according to the theoretical copper foil impedance corresponding to the copper foil at the current moment under the target detection temperature and the compensation impedance corresponding to the control chip, calculate the main circuit impedance of the battery current measurement circuit at the current moment; according to the main circuit impedance of the battery current measurement circuit at the current moment and the terminal voltage difference of the copper foil at the current moment under the target detection temperature, calculate the measurement current of the battery current measurement circuit at the current moment under the target detection temperature. Among them, by replacing the expensive precision resistor element in the existing battery current measurement circuit with a low-cost copper foil, the cost of the battery current measurement circuit can be greatly reduced; a relatively short preset distance is set between the copper foil and the control chip, and the copper foil is electrically connected to the control chip, which can ensure the measurement accuracy of the control chip. In this way, the effect of measuring the battery current with high precision and reducing the production cost of the battery current measurement circuit can be achieved. Description of the Drawings

[0042] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0043] Figure 1 It is a schematic structural diagram of the first battery current measurement circuit provided by the embodiments of the present application;

[0044] Figure 2 It is a flowchart of the first battery current measurement method provided by the embodiments of the present application;

[0045] Figure 3 It is a flowchart of the second battery current measurement method provided by the embodiments of the present application;

[0046] Figure 4 It is a temperature-impedance curve graph of a copper foil provided by the embodiments of the present application;

[0047] Figure 5 It is a schematic diagram of a temperature-impedance table of a copper foil provided by the embodiments of the present application;

[0048] Figure 6 It is a flowchart of the third battery current measurement method provided by the embodiments of the present application;

[0049] Figure 7 It is a system flowchart of a battery current measurement method provided by the embodiments of the present application;

[0050] Figure 8 It is a schematic structural diagram of the second battery current measurement circuit provided by the embodiments of the present application;

[0051] Figure 9 It is a schematic structural diagram of an electronic device provided by the embodiments of the present application.

[0052] Description of the drawings: 10: Battery current measurement circuit; 101: Control chip; 102: Copper foil; 103: Battery module; 104: Insurance unit; 105: Switch unit; 20: Electronic device. Detailed implementation manners

[0053] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Apparently, the described embodiments are some but not all of the embodiments of the present application. Usually, the components of the embodiments of the present application described and illustrated herein can be arranged and designed in various different configurations.

[0054] Therefore, the detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application to be protected, but merely represents the selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the scope of protection of the present application.

[0055] Currently, a battery current measurement circuit is often deployed in an electronic device, and a precision resistor component is deployed in the main circuit of the battery current measurement circuit. By measuring the resistance value and the terminal voltage difference of the precision resistor component in the main circuit, and calculating through Ohm's law, the measured current is obtained. However, this solution has the disadvantage of a relatively high cost of the precision resistor component, which results in a relatively high production cost of the battery current measurement circuit.

[0056] Therefore, the embodiments of the present application provide a battery current measurement method. By obtaining the terminal voltage difference of the copper foil and the current value of the control chip at the target detection temperature, and calculating the compensation impedance corresponding to the control chip according to the terminal voltage difference of the copper foil, the current value of the control chip, the target detection temperature, and the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature; calculating the main circuit impedance of the battery current measurement circuit according to the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature and the compensation impedance corresponding to the control chip; and calculating the measured current of the battery current measurement circuit at the target detection temperature according to the main circuit impedance and the terminal voltage difference of the copper foil. In this way, the effect of high-precision measurement of the battery current and reduction of the production cost of the battery current measurement circuit can be achieved.

[0057] It should be noted that in the prior art, the current value of the battery power supply main circuit is calculated by measuring the resistance value of the precision resistor element deployed on the battery power supply main circuit and the voltage difference between both ends. However, the cost of the precision resistor element is relatively high, which will further increase the production cost of the battery current measurement circuit. However, in the present application, the copper foil is used to replace the precision resistor element in the prior art. By obtaining the actual impedance of the copper foil and each detection temperature, the theoretical impedance and compensation impedance of the copper foil are calculated, and the main circuit impedance is calculated according to the theoretical impedance and compensation impedance. Based on the actual terminal voltage difference of the copper foil and the main circuit impedance, the measured current is obtained. In this way, the copper foil with low cost is used to replace the precision resistor element with high cost, thereby reducing the production cost of the battery current measurement circuit.

[0058] The battery current measurement method and the battery current measurement circuit provided by the embodiments of the present application are explained in detail below with reference to the accompanying drawings.

[0059] Figure 1 The following is a schematic structural diagram of the first battery current measurement circuit provided by the present application. Refer to Figure 1 , the battery current measurement circuit 10 provided by the embodiments of the present application includes: a control chip 101 and a copper foil 102. Among them, the control chip 101 is electrically connected to the copper foil 102, and a preset distance is set between the copper foil 102 and the control chip 101, so that the control chip 101 can quickly obtain the real-time impedance and real-time operating temperature of the copper foil 102. The control chip 101 can be implemented by a Gauge IC, and the present application does not make specific limitations on this.

[0060] Optionally, a battery current measurement algorithm is pre - deployed in the control chip 101. The control chip 101 can calculate the main circuit current of the battery power supply circuit based on the internal algorithm and the acquired electrical parameter information.

[0061] Optionally, the copper foil 102 is a kind of cathodic electrolyte material, a thin and continuous metal foil deposited on the base layer of the circuit board. The copper foil 102 is made by beating copper with a certain proportion of other metals, and the production cost of the copper foil 102 is extremely low.

[0062] Optionally, the preset distance can be any value between 0.5 mm and 3 mm. The copper foil 102 is located below the control chip 101, and there is a relatively close preset distance between the copper foil 102 and the control chip 101, which can ensure that the copper foil 102 can well collect the temperature of the control chip 101 without affecting the power change of the control chip 101.

[0063] It should be noted that the battery current measurement method provided in the embodiments of the present application is mainly applied to the battery current detection of computer devices, but it does not mean that the battery current measurement method provided in the embodiments of the present application is only applicable to the battery current detection of computer devices. The present application does not make specific limitations on this.

[0064] Figure 2 The following is a flowchart of the first battery current measurement method provided by the present application. This method is applied to Figure 1 the control chip 101 in the battery current measurement circuit 10 described above. Refer to Figure 2 , the battery current measurement method provided by the embodiments of the present application includes:

[0065] S201. Obtain the terminal voltage difference of the copper foil and the current value of the control chip at the target detection temperature.

[0066] Optionally, the target detection temperature refers to the ambient temperature around the control chip at the current moment or the actual operating temperature of the copper foil at the current moment. Among them, the ambient temperature around the control chip is approximately equal to the actual operating temperature of the copper foil.

[0067] Optionally, the control chip is connected to both ends of the copper foil. The control chip collects the voltage values at both ends of the copper foil in real - time through the two ends electrically connected to the copper foil, and determines the terminal voltage difference of the copper foil at the target detection temperature at the current moment according to the voltage values at both ends of the copper foil. Among them, the terminal voltage difference refers to the potential difference between the voltage values at both ends of the copper foil.

[0068] Optionally, the current value at the current moment refers to the current value flowing through the inside of the control chip at the current moment. The control chip can obtain the current value through built - in current - collecting components such as ammeters and current meters. The present application does not make specific limitations on this.

[0069] S202. Determine the compensation impedance corresponding to the control chip according to the terminal voltage difference of the copper foil, the current value of the control chip at present, the target detection temperature, and the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature, where the theoretical copper foil impedance is determined based on multiple actual copper foil impedances at the obtained detection temperatures.

[0070] Optionally, calculate the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature according to the actual copper foil impedance of the copper foil at the target detection temperature and the temperature value indicated by the target detection temperature; calculate the compensation impedance corresponding to the control chip according to the terminal voltage difference of the copper foil at the target detection temperature, the current value of the control chip at present, the target detection temperature, and the theoretical copper foil impedance of the copper foil at the target detection temperature. Herein, the compensation impedance refers to the impedance value that the control chip needs to compensate the copper foil at the target detection temperature at the current moment.

[0071] Optionally, the detection temperature can be the actual operating temperature of the copper foil, and the detection temperature can also be the working environment temperature of the control chip. The detection temperature is mainly collected by a temperature acquisition device such as a thermometer or a temperature sensor built in the control chip. This application does not make specific limitations on this.

[0072] Optionally, the actual copper foil impedance refers to the true impedance value of the copper foil at each detection temperature. The control chip obtains the true impedance value of the copper foil at each detection temperature through a sampling terminal connected to the copper foil, and calculates the theoretical impedance value of the copper foil at each detection temperature according to the mapping relationship between the true impedance value of the copper foil impedance and each detection temperature.

[0073] Optionally, the theoretical copper foil impedance refers to the ideal impedance value of the copper foil at each detection temperature, that is, the theoretical copper foil impedance refers to the impedance value of the copper foil in an ideal state, and the actual copper foil impedance refers to the true impedance value of the copper foil affected by the external environment.

[0074] It should be noted that the copper foil impedance refers to the hindering effect of the copper foil on the alternating current flowing through the battery current measurement circuit, and the hindering effect of the copper foil on the alternating current flowing through the battery current measurement circuit is affected by temperature.

[0075] Optionally, the control chip can perform impedance compensation on the copper foil based on the calculated compensation impedance to improve the power capacity of the copper foil.

[0076] S203. Determine the main circuit impedance of the battery current measurement circuit according to the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature and the compensation impedance corresponding to the control chip.

[0077] Optionally, based on the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature and the compensation impedance corresponding to the control chip at the target detection temperature, the main circuit impedance of the battery current measurement circuit can be calculated. Herein, the main circuit impedance refers to the total impedance of the battery current measurement circuit, and the main circuit impedance seriously affects the safety and stability of the battery current measurement circuit.

[0078] S204. Obtain the measured current of the battery current measurement circuit at the target detection temperature according to the main circuit impedance and the voltage difference at both ends of the copper foil.

[0079] Optionally, by substituting the main circuit impedance and the voltage difference at both ends of the copper foil into Ohm's law I = U / R, the measured current of the battery current measurement circuit at the target detection temperature at the current moment can be calculated. The measured current indicates the current value of the battery detected by the battery current measurement circuit at the current moment.

[0080] In the embodiment of the present application, the control chip collects the detection temperature in real time through the built-in temperature acquisition device, and at the same time obtains the voltage difference at both ends of the copper foil at the target detection temperature at the current moment through the ports connecting the control chip to both ends of the copper foil, and obtains the current value flowing through the control chip at the current moment through the current acquisition component built in the control chip; according to the voltage difference at both ends of the copper foil at the target detection temperature at the current moment and the theoretical copper foil impedance, the current value of the control chip, and the temperature value indicated by the target detection temperature, the compensation impedance corresponding to the control chip is calculated; according to the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature at the current moment and the compensation impedance corresponding to the control chip, the main circuit impedance of the battery current measurement circuit at the current moment is calculated; according to the main circuit impedance of the battery current measurement circuit at the current moment and the voltage difference at both ends of the copper foil at the target detection temperature at the current moment, the measured current of the battery current measurement circuit at the target detection temperature at the current moment is calculated. Herein, by replacing the expensive precision resistor element in the existing battery current measurement circuit with a low-cost copper foil, the cost of the battery current measurement circuit can be greatly reduced; the copper foil is deployed directly below the control chip and is electrically connected to the control chip, which can ensure the measurement accuracy of the control chip. In this way, the effect of measuring the battery current with high precision and reducing the production cost of the battery current measurement circuit can be achieved.

[0081] In a possible implementation manner, referring to Figure 3 , the operation of determining the theoretical copper foil impedance mentioned in step S202 based on the multiple actual copper foil impedances at each detection temperature can specifically be:

[0082] S301. According to each detection temperature and the corresponding actual copper foil impedance, fit the temperature-impedance curve corresponding to the battery current measurement circuit.

[0083] Optionally, according to the mapping relationship between each detected temperature and each actual copper foil impedance, a temperature-impedance curve corresponding to the battery current measurement circuit is obtained by fitting. The temperature-impedance curve is used to describe the linear relationship between each detected temperature and the main circuit impedance of the battery current measurement circuit.

[0084] S302. Determine the first impedance factor, the second impedance factor, the third impedance factor, and the fourth impedance factor of the copper foil according to the corresponding relationship between the detected temperature and the main circuit impedance indicated by the temperature-impedance curve.

[0085] Optionally, the main circuit impedance refers to the sum of the compensation impedance of the control chip in the battery current measurement circuit and the theoretical copper foil impedance of the copper foil at each detected temperature.

[0086] Optionally, the first impedance factor, the second impedance factor, the third impedance factor, and the fourth impedance factor are all influencing factors that affect the impedance value of the copper foil. The first impedance factor, the second impedance factor, the third impedance factor, and the fourth impedance factor are only used to distinguish the number of impedance factors and do not represent the magnitude of the influence degree of the impedance factors.

[0087] Optionally, according to the linear relationship between multiple detected temperatures and multiple main circuit impedances indicated by the temperature-impedance curve, the value results of the first impedance factor, the second impedance factor, the third impedance factor, and the fourth impedance factor that affect the copper foil impedance are calculated.

[0088] It should be noted that the first impedance factor, the second impedance factor, the third impedance factor, and the fourth impedance factor are calculation factor constants that affect the actual copper foil impedance of the copper foil and have no actual physical meaning.

[0089] S303. Determine the theoretical copper foil impedance corresponding to the copper foil at each detected temperature according to the first impedance factor, the second impedance factor, the third impedance factor, the fourth impedance factor, and each detected temperature.

[0090] Optionally, according to the first impedance factor, the second impedance factor, the third impedance factor, the fourth impedance factor, and the detected temperature value at the current moment, the theoretical copper foil impedance corresponding to the copper foil at the detected temperature at the current moment can be calculated.

[0091] It should be noted that the main circuit impedance of the battery current measurement circuit is a theoretical impedance, and the main circuit impedance of the battery current measurement circuit is the total impedance calculated according to the theoretical copper foil impedance of the copper foil and the compensation impedance of the control chip.

[0092] In an optional implementation manner, Figure 4 This is a temperature-impedance curve diagram of a copper foil provided by this application. See Figure 4, according to each detected temperature and the actual copper foil impedance of the copper foil at each detected temperature, a temperature-impedance curve between each detected temperature and the main circuit impedance of the battery current measurement circuit is fitted. Figure 4 There is a linear relationship between the main circuit impedance of the battery current measurement circuit and each detected temperature. As the temperature value of the detected temperature increases, the main circuit impedance of the battery current measurement circuit also rises positively.

[0093] In a possible implementation, the operation of step S303 can specifically be:

[0094] Calculate the first product between the first impedance factor and the cube of the detected temperature;

[0095] Calculate the second product between the second impedance factor and the square of the detected temperature;

[0096] Calculate the third product between the third impedance factor and the detected temperature;

[0097] Calculate the sum of the first product, the second product, the third product, and the fourth impedance factor to obtain the theoretical copper foil impedance corresponding to the copper foil at each detected temperature.

[0098] Optionally, the theoretical copper foil impedance of the copper foil at each detected temperature can be calculated according to the following formula (1), and formula (1) is as follows:

[0099] R1 = a×T^3 + b×T^2 + c×T + d (1)

[0100] It should be noted that R1 is used to represent the theoretical copper foil impedance corresponding to the copper foil at the detected temperature T, a is used to represent the first impedance factor of the copper foil, b is used to represent the second impedance factor of the copper foil, c is used to represent the third impedance factor of the copper foil, d is used to represent the fourth impedance factor of the copper foil, and T is used to represent the detected temperature value at the current moment.

[0101] Among them, the first impedance factor a, the second impedance factor b, the third impedance factor c, and the fourth impedance factor d can be either positive or negative, and this application does not make specific limitations on this. It should be noted that in order to improve the acquisition accuracy of the actual operating temperature of the copper foil, the copper foil is set directly below the control chip, and in order to improve the impedance acquisition accuracy of the copper foil, the fourth impedance factor d can be calibrated and adjusted under different temperature conditions.

[0102] Optionally, the calculated first impedance factor a, second impedance factor b, third impedance factor c, and fourth impedance factor d are configured into the control chip, and the control chip can calculate the theoretical copper foil impedance corresponding to the copper foil at this temperature based on the real-time detected temperature value and the actual copper foil impedance of the copper foil.

[0103] In an alternative implementation,Figure 5 A schematic diagram of the temperature-impedance table of the copper foil provided for this application. Refer to Figure 5 , the actual impedance is used to indicate the actual main circuit impedance of the battery current measurement circuit at the detected temperature, the theoretical impedance is used to indicate the main circuit impedance of the battery current measurement circuit at the detected temperature, the error rate is used to indicate the error between the theoretical impedance and the actual impedance of the battery current measurement circuit, the theoretical impedance of the battery current measurement circuit is calculated from the theoretical copper foil impedance and the compensation impedance of the control chip, and the actual impedance of the battery current measurement circuit is the impedance directly measured.

[0104] In a possible implementation, refer to Figure 6 , the operation of step S202 can specifically be:

[0105] S601. Determine the actual resistance value of the copper foil at the target detection temperature according to the voltage difference at both ends of the copper foil and the current value of the control chip at the current moment.

[0106] Optionally, in a relatively stable temperature environment, collect the voltage values at both ends of the copper foil through the cables connected to both ends of the copper foil by the control chip, and calculate the voltage difference at both ends of the copper foil. At the same time, obtain the current value of the control chip at the current moment through the current acquisition device built in the control chip.

[0107] S602. Determine the compensation impedance corresponding to the control chip according to the actual resistance value of the copper foil at the target detection temperature and the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature.

[0108] Optionally, obtain the compensation impedance that the control chip should provide according to the difference between the actual resistance value of the copper foil at the target detection temperature and the theoretical copper foil impedance at the current moment.

[0109] In a possible implementation, the operation of step S601 can specifically be:

[0110] Calculate the first ratio between the voltage difference at both ends of the copper foil and the current value of the control chip at the current moment;

[0111] Determine the actual resistance value of the copper foil at the target detection temperature according to the first ratio.

[0112] Optionally, the actual resistance value of the copper foil at the target detection temperature at the current moment can be calculated according to the following formula (2), and formula (2) is as follows:

[0113] Ra = V1 ÷ I1 (2)

[0114] It should be noted that Ra is used to represent the actual resistance value of the copper foil at the target detection temperature at the current moment, V1 is used to represent the voltage difference at both ends of the copper foil at the target detection temperature at the current moment, and I1 is used to represent the current value of the control chip at the target detection temperature at the current moment.

[0115] In a possible implementation, the operation in step S602 can specifically be as follows:

[0116] Calculate the difference between the actual resistance of the copper foil at the target detection temperature and the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature;

[0117] Determine the compensation impedance corresponding to the control chip according to the difference.

[0118] Optionally, the compensation impedance that the control chip should provide at the target detection temperature at the current moment can be calculated according to the following formula (3), and formula (3) is as follows:

[0119] R2 = Ra - R1 (3)

[0120] It should be noted that R2 is used to represent the compensation impedance corresponding to the control chip at the target detection temperature at the current moment, Ra is used to represent the actual resistance of the copper foil at the target detection temperature at the current moment, and R1 is used to represent the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature at the current moment.

[0121] In a possible implementation, the operation in step S203 can specifically be as follows:

[0122] Calculate the sum of the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature and the compensation impedance corresponding to the control chip to obtain the main circuit impedance of the battery current measurement circuit.

[0123] Optionally, the main circuit impedance of the battery current measurement circuit at the target detection temperature at the current moment can be calculated according to the following formula (4), and formula (4) is as follows:

[0124] R = [a×T^3 + b×T^2 + c×T + d] + R2 (4)

[0125] It should be noted that R is used to represent the main circuit impedance of the battery current measurement circuit at the target detection temperature at the current moment, a is used to represent the first impedance factor of the copper foil, b is used to represent the second impedance factor of the copper foil, c is used to represent the third impedance factor of the copper foil, d is used to represent the fourth impedance factor of the copper foil, T is used to represent the detection temperature value at the current moment, and R2 is used to represent the compensation impedance corresponding to the control chip at the target detection temperature at the current moment.

[0126] In a possible implementation, the operation in step S204 can specifically be as follows:

[0127] Calculate the second ratio between the terminal voltage difference of the copper foil and the main circuit impedance to obtain the measured current measured by the battery current measurement circuit at the target detection temperature.

[0128] Optionally, the measured current measured by the battery current measurement circuit at the target detection temperature at the current moment can be calculated according to the following formula (5), and the formula (5) is as follows:

[0129] I = V1 ÷ R (5)

[0130] It should be noted that I is used to represent the measured current measured by the battery current measurement circuit at the target detection temperature at the current moment, V1 is used to represent the terminal voltage difference of the copper foil at the target detection temperature at the current moment, and R is used to represent the main circuit impedance of the battery current measurement circuit at the target detection temperature at the current moment.

[0131] Figure 7 The system flowchart of a battery current measurement method provided by this application is shown in Figure 7 , test the actual copper foil impedance of the copper foil at multiple detection temperatures such as 0°C to 60°C; and according to the actual copper foil impedance of the copper foil at multiple detection temperatures such as 0°C to 60°C, fit the theoretical temperature impedance curve of the battery current measurement circuit; calculate the first impedance factor, the second impedance factor, the third impedance factor, and the fourth impedance factor of the copper foil, and configure them into the control chip; the control chip calculates the compensation impedance according to the real-time temperature and the actual copper foil impedance of the copper foil, and performs impedance compensation on the actual copper foil impedance of the copper foil; the control chip calculates the measured current of the battery current measurement circuit according to the terminal voltage difference of the copper foil at the current moment and the compensated main circuit impedance.

[0132] In an optional implementation manner, see Figure 8 , the battery current measurement circuit 10 provided in the embodiment of this application includes: a battery module 103, a fuse unit 104, a switch unit 105, a copper foil 102, and a control chip 101.

[0133] The first end of the battery module 103 is respectively connected to the first end of the control chip 101 and the first end of the fuse unit 104, the second end of the battery module 103 is connected to the second end of the control chip 101, and the third end of the battery module 103 is respectively connected to one end of the copper foil 102 and the first sampling end of the control chip 101;

[0134] The second end of the fuse unit 104 is connected to the first end of the switch unit 105, the control end of the fuse unit 104 is connected to the third end of the control chip 101, and the third end of the fuse unit 104 is connected to the copper foil 102;

[0135] The second end of the switch unit 105 is connected to the positive power supply port, the control end of the switch unit 105 is connected to the fourth end of the control chip 101, the second sampling end of the control chip 101 is connected to the other end of the copper foil 102, and the copper foil 102 is also used to connect to the negative power supply port;

[0136] The control chip 101 is used to implement any of the embodiments of the above battery current measurement method.

[0137] Figure 9 It is a schematic structural diagram of an electronic device provided by an embodiment of the present application. Refer to Figure 9 , the electronic device 20 provided by the embodiment of the present application includes: a battery current measurement circuit 10, and the electronic device 20 implements the steps in any of the above method embodiments through the control chip 101 in the battery current measurement circuit 10.

[0138] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present application, and all should be covered by the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

[0139] The above are only the preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for measuring battery current, characterized in that, The method is applied to a control chip in a battery current measurement circuit. A copper foil is also provided in the battery current measurement circuit. The control chip is connected to the copper foil, and a preset distance is provided between the copper foil and the control chip. The method includes: Obtaining the terminal voltage difference of the copper foil and the current value of the control chip at a target detection temperature; Determining the compensation impedance corresponding to the control chip according to the terminal voltage difference of the copper foil, the current value of the control chip, the target detection temperature, and the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature, where the theoretical copper foil impedance is determined based on a plurality of actual copper foil impedances at various detected temperatures obtained; Determining the main circuit impedance of the battery current measurement circuit according to the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature and the compensation impedance corresponding to the control chip; Obtaining the measurement current of the battery current measurement circuit at the target detection temperature according to the main circuit impedance and the terminal voltage difference of the copper foil.

2. The battery current measurement method according to claim 1, wherein The theoretical copper foil impedance is determined based on a plurality of actual copper foil impedances at various detected temperatures obtained, including: Fitting a temperature-impedance curve corresponding to the battery current measurement circuit according to each detected temperature and the corresponding actual copper foil impedance; Determining a first impedance factor, a second impedance factor, a third impedance factor, and a fourth impedance factor of the copper foil according to the corresponding relationship between the detected temperature and the main circuit impedance indicated by the temperature-impedance curve; Determining the theoretical copper foil impedance corresponding to the copper foil at each detected temperature according to the first impedance factor, the second impedance factor, the third impedance factor, the fourth impedance factor, and each detected temperature.

3. The battery current measurement method according to claim 2, characterized in that The determining the theoretical copper foil impedance corresponding to the copper foil at each detected temperature according to the first impedance factor, the second impedance factor, the third impedance factor, the fourth impedance factor, and each detected temperature includes: Calculating a first product between the first impedance factor and the cube of the detected temperature; Calculating a second product between the second impedance factor and the square of the detected temperature; Calculating a third product between the third impedance factor and the detected temperature; Calculating the sum of the first product, the second product, the third product, and the fourth impedance factor to obtain the theoretical copper foil impedance corresponding to the copper foil at each detected temperature.

4. The battery current measurement method according to claim 1, wherein The determining the compensation impedance corresponding to the control chip according to the terminal voltage difference of the copper foil, the current value of the control chip, the target detection temperature, and the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature includes: Determining the actual resistance value of the copper foil at the target detection temperature according to the terminal voltage difference of the copper foil and the current value of the control chip; Determining the compensation impedance corresponding to the control chip according to the actual resistance value of the copper foil at the target detection temperature and the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature.

5. The battery current measurement method according to claim 4, wherein Determining the actual resistance value of the copper foil at the target detection temperature according to the terminal voltage difference of the copper foil and the current value of the control chip includes: Calculating a first ratio between the terminal voltage difference of the copper foil and the current value of the control chip; Determining the actual resistance value of the copper foil at the target detection temperature according to the first ratio.

6. The battery current measurement method according to claim 4, wherein Determining the compensation impedance corresponding to the control chip according to the actual resistance value of the copper foil at the target detection temperature and the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature includes: Calculating a difference between the actual resistance value of the copper foil at the target detection temperature and the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature; Determining the compensation impedance corresponding to the control chip according to the difference.

7. The battery current measurement method according to claim 1, characterized in that Determining the main circuit impedance of the battery current measurement circuit according to the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature and the compensation impedance corresponding to the control chip includes: Calculating the sum of the theoretical copper foil impedance corresponding to the copper foil at the target detection temperature and the compensation impedance corresponding to the control chip to obtain the main circuit impedance of the battery current measurement circuit.

8. The battery current measurement method according to claim 1, wherein, Obtaining the measurement current of the battery current measurement circuit at the target detection temperature according to the main circuit impedance and the terminal voltage difference of the copper foil includes: Calculating a second ratio between the terminal voltage difference of the copper foil and the main circuit impedance to obtain the measurement current measured by the battery current measurement circuit at the target detection temperature.

9. A battery current measurement circuit, characterized in that, The battery current measurement circuit includes: a battery module, a fuse unit, a switch unit, a copper foil, and a control chip; The first end of the battery module is respectively connected to the first end of the control chip and the first end of the fuse unit, the second end of the battery module is connected to the second end of the control chip, and the third end of the battery module is respectively connected to one end of the copper foil and the first sampling end of the control chip; The second end of the fuse unit is connected to the first end of the switch unit, the control end of the fuse unit is connected to the third end of the control chip, and the third end of the fuse unit is connected to the copper foil; The second end of the switch unit is connected to the positive power supply port, the control end of the switch unit is connected to the fourth end of the control chip, the second sampling end of the control chip is connected to the other end of the copper foil, and the copper foil is further used to connect to the negative power supply port; The control chip is used to execute the steps of the battery current measurement method according to any one of claims 1-8.

10. An electronic device, characterized in that, The battery current measurement circuit according to claim 9 is deployed in the electronic device.

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