Battery detection circuit and system

Abstract

This application relates to a battery detection circuit and system. The battery detection circuit includes a signal processing module and a current regulation module; wherein, the first and second terminals of the signal processing module and the first output terminal of the current regulation module are respectively connected to the first terminal of the battery under test, the third and fourth terminals of the signal processing module and the second output terminal of the current regulation module are respectively connected to the second terminal of the battery under test, and the first input terminal of the current regulation module is connected to the fifth terminal of the signal processing module; the signal processing module is used to provide an excitation current to the battery under test and to provide a pulse width modulation signal to the current regulation module; the current regulation module is used to adjust the excitation current under the action of the pulse width modulation signal; the signal processing module is also used to detect the response voltage generated by the battery under test in response to the excitation current, and to determine the internal resistance of the battery under test based on the response voltage and the adjusted excitation current. The battery detection circuit of this application has a simple structure and low cost.

Description

Technical Field

[0001] This application relates to the field of battery testing technology, and in particular to a battery testing circuit and system. Background Technology

[0002] Cell voltage and internal resistance testing are crucial for assessing battery condition, ensuring safety, optimizing performance, extending lifespan, and reducing costs, making them a key component of the Battery Management System (BMS). Current battery testing modules suffer from complex structures and high costs. Utility Model Content

[0003] Therefore, it is necessary to provide a battery detection circuit and system.

[0004] In a first aspect, this application provides a battery detection circuit, including: a signal processing module and a current regulation module;

[0005] Wherein, the first and second terminals of the signal processing module and the first output terminal of the current regulation module are respectively connected to the first pole of the battery under test, the third and fourth terminals of the signal processing module and the second output terminal of the current regulation module are respectively connected to the second pole of the battery under test, and the first input terminal of the current regulation module is connected to the fifth terminal of the signal processing module.

[0006] The signal processing module is used to provide excitation current to the battery under test and to provide pulse width modulation signal to the current regulation module;

[0007] The current adjustment module is used to adjust the excitation current under the action of the pulse width modulation signal;

[0008] The signal processing module is also used to detect the response voltage generated by the battery under test in response to the excitation current, and to determine the internal resistance of the battery under test based on the response voltage and the adjusted excitation current.

[0009] In one embodiment, the current regulation module includes:

[0010] A first resistor, the first end of which is connected to the second terminal of the battery under test and the fourth terminal of the signal processing module;

[0011] A filtering unit, the first end of which is connected to the fifth end of the signal processing module, is used to convert the pulse width modulation signal into a sine signal;

[0012] A transistor, the gate of which is connected to the second terminal of the filter unit, the first terminal of which is connected to the first terminal of the battery under test and the second terminal of the signal processing module, and the second terminal of which is connected to the second terminal of the first resistor, wherein the transistor is used to select and conduct the path between the first resistor and the first terminal of the battery under test under the action of the sinusoidal signal.

[0013] In one embodiment, the signal processing module is further configured to provide a DC offset signal;

[0014] The current regulation module further includes:

[0015] An operational amplifier is provided, wherein the non-inverting input terminal of the operational amplifier is connected to the second terminal of the filtering unit, and the inverting input terminal of the operational amplifier is connected to the sixth terminal of the signal processing module, the output terminal of the operational amplifier, and the gate of the transistor. The operational amplifier is used to receive the DC offset signal through the inverting input terminal and adjust the voltage of the sine signal according to the DC offset signal. The adjusted sine signal is greater than the turn-on voltage of the transistor throughout the entire cycle.

[0016] In one embodiment, the first end of the first resistor is also connected to the seventh end of the signal processing module, and the second end of the first resistor is also connected to the eighth end of the signal processing module.

[0017] The signal processing module is also used to acquire the voltage across the first resistor and adjust the pulse width modulation signal based on the voltage feedback across the first resistor.

[0018] The current regulation module is also used to adjust the excitation current to a preset current value under the action of the pulse width modulation signal after feedback regulation.

[0019] In one embodiment, the battery detection circuit further includes:

[0020] A temperature-sensitive module, wherein the first end of the temperature-sensitive module is connected to the second electrode of the battery under test, the second end of the temperature-sensitive module is connected to the ninth end of the signal processing module, and the third end of the temperature-sensitive module is connected to the tenth end of the signal processing module;

[0021] The signal processing module is further configured to provide a reference voltage to the battery under test through the temperature sensing module, acquire the voltage across the temperature sensing module, and determine the temperature of the battery under test based on the reference voltage and the voltage across the temperature sensing module.

[0022] In one embodiment, the temperature-sensitive module includes a second resistor and a thermistor;

[0023] The first end of the second resistor is connected to the ninth end of the signal processing module, the second end of the second resistor is connected to the first end of the thermistor and the tenth end of the signal processing module, and the second end of the thermistor is connected to the second electrode of the battery under test.

[0024] In one embodiment, the battery detection circuit further includes:

[0025] A first filtering module, wherein a first end of the first filtering module is connected to the first pole of the battery under test and the first output end of the current regulation module, and a second end of the first filtering module is connected to the second end of the signal processing module, and the first filtering module is used to filter the response voltage;

[0026] The second filtering module has its first end connected to the second terminal of the battery under test and the second output terminal of the current regulation module, and its second end connected to the fourth terminal of the signal processing module. The second filtering module is used to filter the response voltage.

[0027] In one embodiment, the battery detection circuit further includes:

[0028] A protection module is provided, wherein the first end of the protection module is connected to the second end of the signal processing module and the first terminal of the battery under test, and the second end of the protection module is connected to the first output terminal of the current regulation module. The protection module is used to disconnect the path between the current regulation module and the first terminal of the battery under test when a preset protection condition is met.

[0029] In one embodiment, the battery detection circuit further includes:

[0030] The third resistor has its first end connected to the first terminal of the battery under test, and its second end connected to the first end of the signal processing module.

[0031] A fourth resistor, the first end of which is connected to the second end of the third resistor and the first end of the signal processing module, and the second end of the fourth resistor is connected to the third end of the signal processing module and the second terminal of the battery under test;

[0032] The third resistor and the fourth resistor are used to perform voltage division processing on the excitation signal provided by the signal processing module to the battery under test.

[0033] Secondly, this application provides a battery testing system, including a battery under test and a battery testing circuit provided in any of the above embodiments.

[0034] In the aforementioned battery detection circuit and system, the battery detection circuit includes a signal processing module and a current regulation module. The signal processing module provides an excitation current to the battery under test and a pulse width modulation (PWM) signal to the current regulation module. Under the influence of the PWM signal, the current regulation module adjusts the excitation current. Furthermore, the signal processing module detects the response voltage generated by the battery under test in response to the excitation current, and determines the internal resistance of the battery under test based on the response voltage and the adjusted excitation current, thus achieving accurate measurement of the battery's internal resistance. Moreover, the battery detection circuit of this application has a simple structure and low cost. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a structural block diagram of a battery detection circuit provided in one embodiment;

[0037] Figure 2 Pin diagram of the DSPIC33FJ32MC202 chip;

[0038] Figure 3 This is a circuit diagram of a current detection module provided in one embodiment;

[0039] Figure 4 A circuit diagram of the temperature sensing module of a current detection module provided in one embodiment;

[0040] Figure 5 A structural block diagram of a battery detection circuit provided in another embodiment. Detailed Implementation

[0041] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0043] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0044] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0045] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.

[0046] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0047] In one embodiment, such as Figure 1 As shown, this application provides a battery detection circuit, including a signal processing module 100 and a current regulation module 200.

[0048] In this configuration, the first and second terminals of the signal processing module 100 and the first output terminal of the current adjustment module 200 are connected to the first terminal of the battery under test 300. The third and fourth terminals of the signal processing module 100 and the second output terminal of the current adjustment module 200 are connected to the second terminal of the battery under test 300. The first input terminal of the current adjustment module 200 is connected to the fifth terminal of the signal processing module 100. The first terminal of the battery under test 300 is positive, the second terminal is negative, and the second terminal of the battery under test 300 and the third terminal of the signal processing module 100 are grounded.

[0049] The signal processing module 100 provides excitation current to the battery under test 300 and pulse width modulation (PWM) signals to the current regulation module 200. It can be understood that the signal processing module 100 outputs the excitation current through the first and third terminals and the pulse width modulation signal through the fifth terminal. The signal processing module 100 can be a DSP, microcontroller, or MCU, etc. For example, the signal processing module 100 can be a DSPIC33FJ32MC202 chip, and its pin diagram is shown below. Figure 2 As shown, a digital filter is configured in the signal processing module 100. The out-of-band attenuation of the digital filter is 80dB within a preset filtering frequency range. For example, the preset filtering frequency range is 1KHz to 2KHz.

[0050] The current regulation module 200 is used to regulate the excitation current under the action of a pulse width modulation signal. Under the action of the pulse width modulation signal, the current regulation module 200 can adjust the excitation current provided by the signal processing module 100 to the battery under test 300 to an AC signal that meets a preset frequency and a preset current value. For example, the preset frequency can be 1 kHz.

[0051] The signal processing module 100 is also used to detect the response voltage of the battery under test 300 in response to the excitation current, and to determine the internal resistance of the battery under test 300 based on the response voltage and the adjusted excitation current. After the excitation current is applied to the battery under test 300, the signal processing module 100 can receive the response voltage of the battery under test 300 through the second and fourth terminals, and perform amplification processing, analog-to-digital conversion processing, and frequency domain analysis on the response voltage of the battery under test 300 and the adjusted excitation current to determine the internal resistance of the battery under test 300.

[0052] In this embodiment, the battery detection circuit includes a signal processing module 100 and a current regulation module 200. The signal processing module 100 provides an excitation current to the battery under test 300 and a pulse width modulation signal to the current regulation module 200. Under the action of the pulse width modulation signal, the current regulation module 200 adjusts the excitation current. Furthermore, the signal processing module 100 detects the response voltage generated by the battery under test 300 in response to the excitation current, and determines the internal resistance of the battery under test 300 based on the response voltage and the adjusted excitation current, thus achieving accurate measurement of the battery's internal resistance. Moreover, the battery detection circuit of this application has a simple structure and low cost.

[0053] In one embodiment, such as Figure 3As shown, the current regulation module 200 includes a first resistor R1, a filter unit 210, and a transistor Q1. The first terminal of the first resistor R1 is connected to the second terminal of the battery under test 300 and the fourth terminal of the signal processing module 100. The second terminal of the first resistor R1 is connected to the second terminal of the transistor Q1. The gate of the transistor Q1 is connected to the second terminal of the filter unit 210. The first terminal of the transistor Q1 is connected to the first terminal of the battery under test 300 and the second terminal of the signal processing module 100. The first terminal of the filter unit 210 is also connected to the fifth terminal of the signal processing module 100. The first terminal of the transistor Q1 can be either the source or the drain, and the second terminal of the transistor Q1 can be either the source or the drain. For example, the resistance of the first resistor R1 is 0.1Ω, and the power is 3W.

[0054] The filtering unit 210 is used to convert the pulse width modulation signal into a sinusoidal signal. Further, the filtering unit 210 may include a fifth resistor R5, a sixth resistor R6, and a first capacitor C1. The first end of the fifth resistor R5 is connected to the fifth terminal of the signal processing module 100, and the second end of the fifth resistor R5 is connected to the first end of the sixth resistor R6, the first end of the first capacitor C1, and the gate of transistor Q1. The second ends of the sixth resistor R6 and the second end of the first capacitor C1 are grounded. The cutoff frequency of the filtering unit 210 is much lower than the frequency of the pulse width modulation signal to ensure that a smooth sinusoidal signal can be output.

[0055] Transistor Q1 is used to select and conduct the path between the first resistor R1 and the first terminal of the battery under test 300 under the action of a sinusoidal signal. The sinusoidal signal flows into the gate of transistor Q1, causing transistor Q1 to conduct, thereby opening the path between the first resistor R1 and the first terminal of the battery under test 300. The first resistor R1 and the battery's internal resistance are connected in parallel. Because a new resistor (i.e., the first resistor R1) is connected in the test circuit, the excitation current flowing through the battery's internal resistance is changed, and the fundamental frequency of the adjusted excitation current is the same as the frequency of the sinusoidal signal.

[0056] In this embodiment, the current adjustment module 200 includes a first resistor R1, a filter unit 210, and a transistor Q1. By setting the filter unit 210, the pulse width modulation signal output by the signal processing module 100 can be converted into a smooth sine signal, and the sine signal is applied to the gate of the transistor Q1 to turn on the transistor Q1, thereby making the path between the first resistor R1 and the first terminal of the battery under test 300 open, thus changing the frequency and current value of the excitation current flowing to the battery under test 300.

[0057] In one embodiment, such as Figure 3As shown, the current regulation module 200 also includes an operational amplifier U1. The non-inverting input terminal of the operational amplifier U1 is connected to the second terminal of the filter unit 210, and the inverting input terminal of the operational amplifier U1 is connected to the sixth terminal of the signal processing module 100, the output terminal of the operational amplifier U1, and the gate of the transistor Q1, respectively.

[0058] The signal processing module 100 is also used to provide a DC offset signal. Specifically, the DC offset signal can be output through the sixth terminal of the signal processing module 100. The voltage value of the DC offset signal is greater than the turn-on voltage of transistor Q1. The operational amplifier U1 is used to receive the DC offset signal through its inverting input terminal and adjust the voltage of the sine wave signal according to the DC offset signal. The adjusted sine wave signal is greater than the turn-on voltage of transistor Q1 throughout the entire cycle. The operational amplifier U1 is essentially an adder. The non-inverting input terminal of the operational amplifier U1 receives the sine wave signal, and the inverting input terminal receives the DC offset signal. It can superimpose the DC offset signal onto the sine wave signal, making the sine wave signal greater than the turn-on voltage of transistor Q1 throughout the entire cycle, thereby allowing transistor Q1 to conduct throughout the entire cycle. In this way, the frequency of the adjusted excitation current is the same as the frequency of the sine wave signal.

[0059] In one embodiment, such as Figure 3 As shown, the current regulation module 200 also includes a seventh resistor R7 and a second capacitor C2. The first terminal of the second capacitor C2 is connected to the inverting input terminal of the operational amplifier U1, the second terminal of the second capacitor C2 is connected to the first terminal of the seventh resistor R7, and the second terminal of the seventh resistor R7 is connected to the output terminal of the operational amplifier U2. The seventh resistor R7 and the second capacitor C2 constitute an RC filter, which can be used to filter the DC offset signal.

[0060] In one embodiment, the first end of the first resistor R1 is also connected to the seventh end of the signal processing module 100, and the second end of the first resistor R1 is also connected to the eighth end of the signal processing module 100.

[0061] The signal processing module 100 is also used to acquire the voltage across the first resistor R1 and adjust the pulse width modulation signal based on the voltage across the first resistor R1. The signal processing module 100 is configured as a differential input, with its seventh and eighth terminals forming a set of differential input ports. After acquiring the voltage across the first resistor R1, the signal processing module 100 can calculate the actual current flowing through the first resistor R1 based on the voltage across the first resistor R1 and the resistance value of the first resistor R1, thereby obtaining the actual excitation current value. It then calculates the current error based on the actual excitation current value and a preset current value, and adjusts the pulse width modulation signal based on the current error.

[0062] The current regulation module 200 is also used to adjust the excitation current to a preset current value under the action of the pulse width modulation signal after feedback regulation. For example, the preset current value can be 1.5A.

[0063] In one embodiment, such as Figure 4 As shown, the battery detection circuit also includes a temperature-sensitive module 400. The first terminal of the temperature-sensitive module 400 is connected to the second terminal of the battery under test 300, the second terminal of the temperature-sensitive module 400 is connected to the ninth terminal of the signal processing module 100, and the third terminal of the temperature-sensitive module 400 is connected to the tenth terminal of the signal processing module 100.

[0064] The signal processing module 100 is further configured to provide a reference voltage to the battery under test 300 via the temperature sensing module 400, acquire the voltage across the temperature sensing module 400, and determine the temperature of the battery under test 300 based on the reference voltage and the voltage across the temperature sensing module 400. For example, the reference voltage can be 2.048V, and the specific value of the reference voltage can be reasonably set according to the actual usage scenario; this embodiment does not impose any limitations on this.

[0065] Specifically, the temperature-sensitive module 400 includes a second resistor R2 and a thermistor RT. The first end of the second resistor R2 is connected to the ninth terminal of the signal processing module 100, and the second end of the second resistor R2 is connected to both the first end of the thermistor RT and the tenth terminal of the signal processing module 100. The second end of the thermistor RT is connected to the second terminal of the battery under test 300. Since detecting battery temperature generally involves testing the temperature of the battery terminals, the thermistor RT can be attached to the negative copper terminal of the battery under test 300 to more accurately measure its temperature. For example, the resistance of the thermistor RT is 10KΩ at room temperature (25°C), and the resistance of the second resistor R2 can also be 10KΩ.

[0066] In this embodiment, a reference voltage is output through the ninth terminal of the signal processing module 100. This reference voltage flows to the second terminal of the battery under test 300 through the second resistor R2 and the thermistor RT. Since the second terminal of the battery under test 300 is grounded, the voltage across the thermistor RT can be directly obtained through the tenth terminal of the signal processing module 100. Then, the signal processing module 100 determines the temperature of the battery under test 300 according to the correspondence between the voltage of the thermistor RT and the temperature, thus realizing the measurement of the temperature of the battery under test 300.

[0067] In one embodiment, such as Figure 5 As shown, the battery detection circuit also includes a first filter module 500 and a second filter module 600.

[0068] The first terminal of the first filtering module 500 is connected to the first terminal of the battery under test 300 and the first output terminal of the current regulation module 200, and the second terminal of the first filtering module 500 is connected to the second terminal of the signal processing module 100. The first filtering module 500 is used to filter the response voltage. For example, the first filtering module 500 includes a third capacitor C3.

[0069] The first terminal of the second filtering module 600 is connected to the second terminal of the battery under test 300 and the second output terminal of the current adjustment module 200, and the second terminal of the second filtering module 600 is connected to the fourth terminal of the signal processing module 100. The second filtering module 600 is used to filter the response voltage. For example, the second filtering module 600 includes a fourth capacitor C4.

[0070] In one embodiment, the battery detection circuit further includes a protection module 700. A first terminal of the protection module 700 is connected to a second terminal of the signal processing module 100 and a first terminal of the battery under test 300. The second terminal of the protection module 700 is connected to a first output terminal of the current regulation module 200. The protection module 700 is used to disconnect the path between the current regulation module 200 and the first terminal of the battery under test 300 when a preset protection condition is met. For example, the protection module 700 may include a fuse F1, which can disconnect the path between the current regulation module 200 and the first terminal of the battery under test 300 in the event of a current overload, preventing the circuit from burning out.

[0071] In one embodiment, such as Figure 5 As shown, the battery detection circuit also includes a third resistor R3 and a fourth resistor R4. The first end of the third resistor R3 is connected to the first terminal of the battery under test 300, and the second end of the third resistor R3 is connected to the first terminal of the signal processing module 100. The first end of the fourth resistor R4 is connected to the second end of the third resistor R3 and the first terminal of the signal processing module 100, and the second end of the fourth resistor R4 is connected to the third terminal of the signal processing module 100 and the second terminal of the battery under test 300.

[0072] The third resistor R3 and the fourth resistor R4 are used to perform voltage division processing on the excitation signal provided by the signal processing module 100 to the battery under test 300.

[0073] In one embodiment, this application also provides a battery testing system, which may include a battery under test 300 and a battery testing circuit provided in any of the above embodiments.

[0074] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0075] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0076] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A battery detection circuit, characterized in that, include: Signal processing module and current regulation module; Wherein, the first and second terminals of the signal processing module and the first output terminal of the current regulation module are respectively connected to the first pole of the battery under test, the third and fourth terminals of the signal processing module and the second output terminal of the current regulation module are respectively connected to the second pole of the battery under test, and the first input terminal of the current regulation module is connected to the fifth terminal of the signal processing module. The signal processing module is used to provide excitation current to the battery under test and to provide pulse width modulation signal to the current regulation module; The current adjustment module is used to adjust the excitation current under the action of the pulse width modulation signal; The signal processing module is also used to detect the response voltage generated by the battery under test in response to the excitation current, and to determine the internal resistance of the battery under test based on the response voltage and the adjusted excitation current.

2. The battery detection circuit according to claim 1, characterized in that, The current regulation module includes: A first resistor, the first end of which is connected to the second terminal of the battery under test and the fourth terminal of the signal processing module; A filtering unit, the first end of which is connected to the fifth end of the signal processing module, is used to convert the pulse width modulation signal into a sine signal; A transistor, the gate of which is connected to the second terminal of the filter unit, the first terminal of which is connected to the first terminal of the battery under test and the second terminal of the signal processing module, and the second terminal of which is connected to the second terminal of the first resistor, wherein the transistor is used to select and conduct the path between the first resistor and the first terminal of the battery under test under the action of the sinusoidal signal.

3. The battery detection circuit according to claim 2, characterized in that, The signal processing module is also used to provide a DC offset signal; The current regulation module further includes: An operational amplifier is provided, wherein the non-inverting input terminal of the operational amplifier is connected to the second terminal of the filtering unit, and the inverting input terminal of the operational amplifier is connected to the sixth terminal of the signal processing module, the output terminal of the operational amplifier, and the gate of the transistor. The operational amplifier is used to receive the DC offset signal through the inverting input terminal and adjust the voltage of the sine signal according to the DC offset signal. The adjusted sine signal is greater than the turn-on voltage of the transistor throughout the entire cycle.

4. The battery detection circuit according to claim 2, characterized in that, The first end of the first resistor is also connected to the seventh end of the signal processing module, and the second end of the first resistor is also connected to the eighth end of the signal processing module. The signal processing module is also used to acquire the voltage across the first resistor and adjust the pulse width modulation signal based on the voltage feedback across the first resistor. The current regulation module is also used to adjust the excitation current to a preset current value under the action of the pulse width modulation signal after feedback regulation.

5. The battery detection circuit according to any one of claims 1-4, characterized in that, The battery detection circuit also includes: A temperature-sensitive module, wherein the first end of the temperature-sensitive module is connected to the second electrode of the battery under test, the second end of the temperature-sensitive module is connected to the ninth end of the signal processing module, and the third end of the temperature-sensitive module is connected to the tenth end of the signal processing module; The signal processing module is further configured to provide a reference voltage to the battery under test through the temperature sensing module, acquire the voltage across the temperature sensing module, and determine the temperature of the battery under test based on the reference voltage and the voltage across the temperature sensing module.

6. The battery detection circuit according to claim 5, characterized in that, The temperature-sensitive module includes a second resistor and a thermistor; The first end of the second resistor is connected to the ninth end of the signal processing module, the second end of the second resistor is connected to the first end of the thermistor and the tenth end of the signal processing module, and the second end of the thermistor is connected to the second electrode of the battery under test.

7. The battery detection circuit according to any one of claims 1-4, characterized in that, The battery detection circuit also includes: A first filtering module, wherein a first end of the first filtering module is connected to the first pole of the battery under test and the first output end of the current regulation module, and a second end of the first filtering module is connected to the second end of the signal processing module, and the first filtering module is used to filter the response voltage; The second filtering module has its first end connected to the second terminal of the battery under test and the second output terminal of the current regulation module, and its second end connected to the fourth terminal of the signal processing module. The second filtering module is used to filter the response voltage.

8. The battery detection circuit according to any one of claims 1-4, characterized in that, The battery detection circuit also includes: A protection module is provided, wherein the first end of the protection module is connected to the second end of the signal processing module and the first terminal of the battery under test, and the second end of the protection module is connected to the first output terminal of the current regulation module. The protection module is used to disconnect the path between the current regulation module and the first terminal of the battery under test when a preset protection condition is met.

9. The battery detection circuit according to any one of claims 1-4, characterized in that, The battery detection circuit also includes: The third resistor has its first end connected to the first terminal of the battery under test, and its second end connected to the first end of the signal processing module. A fourth resistor, the first end of which is connected to the second end of the third resistor and the first end of the signal processing module, and the second end of the fourth resistor is connected to the third end of the signal processing module and the second terminal of the battery under test; The third resistor and the fourth resistor are used to perform voltage division processing on the excitation signal provided by the signal processing module to the battery under test.

10. A battery testing system, characterized in that, It includes the battery under test and the battery detection circuit as described in any one of claims 1-9.

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