Battery management circuit, battery management chip and vehicle

Abstract

The invention discloses a battery management circuit, a battery chip and a vehicle, and relates to the technical field of batteries. The battery management circuit comprises an amplitude-phase detection module and a waveform generator, and the output end of the waveform generator is connected with the positive electrode of a battery and the first input end of the amplitude-phase detection module; the second input end of the amplitude-phase detection module is connected with the positive electrode of the battery; wherein the waveform generator is used for applying alternating current excitation signals with different frequencies to the battery, and the amplitude and phase detection module is used for detecting the amplitude and phase of impedance of the battery under the alternating current excitation signals with different frequencies. The invention provides a battery management circuit which is a novel battery management system capable of estimating the electric quantity and the service life of a battery, and compared with general voltage and current data, the battery management circuit can better represent dynamic information in the electrode process and the conductivity of a battery material.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and more specifically, to a battery management circuit, a battery management chip and a vehicle. Background Art

[0002] The current battery management system (BMS) estimates the battery power and life by monitoring the changes in battery voltage, current, temperature and other parameters, combined with complex algorithms. However, the estimation accuracy of this method is often not high, and it is highly dependent on the accuracy of voltage, current and temperature detection. In addition, the algorithm has a large amount of calculation and high complexity. Only by using industrial computers can the real-time performance of the system be guaranteed.

[0003] Therefore, how to provide a new battery management system that can estimate battery power and life has become a technical problem that needs to be solved urgently. Summary of the invention

[0004] One object of the present application is to provide a new technical solution for managing batteries.

[0005] According to a first aspect of the present application, a battery management circuit is provided, comprising: an amplitude and phase detection module and a waveform generator, wherein:

[0006] The output end of the waveform generator is connected to the positive electrode of the battery and the first input end of the amplitude and phase detection module respectively;

[0007] The second input terminal of the amplitude and phase detection module is connected to the positive electrode of the battery;

[0008] The waveform generator is used to apply AC excitation signals of different frequencies to the battery, and the amplitude and phase detection module is used to detect the amplitude and phase of the impedance of the battery under the AC excitation signals of different frequencies.

[0009] Optionally, the AC excitation signals of different frequencies are swept frequency triangle wave signals of 0.01 Hz to 500 KHz.

[0010] Optionally, the battery management circuit further includes: an analog-to-digital conversion module, a storage module and a communication module, wherein:

[0011] The amplitude and phase detection module, analog-to-digital conversion module, storage module and communication module are connected in sequence.

[0012] Optionally, the battery management circuit further includes a filtering module, wherein:

[0013] The analog-to-digital conversion module is connected to the storage module through the filtering module.

[0014] Optionally, the battery management circuit further includes: at least one of a voltage acquisition module, a current acquisition module, a temperature acquisition module, and a multiplexer, wherein:

[0015] The voltage acquisition module is connected to the positive electrode of the battery, the negative electrode of the battery and the multiplexer respectively;

[0016] The current acquisition module is connected to the positive electrode of the battery or the negative electrode of the battery, and the current acquisition module is connected to the multiplexer;

[0017] The temperature acquisition module is connected to the multiplexer;

[0018] The amplitude and phase detection module is connected to the multiplexer;

[0019] The multiplexer is connected to the input end of the analog-to-digital conversion module.

[0020] Optionally, the waveform generator comprises: a hysteresis voltage comparator, a first switch unit, a sign circuit, an inverting integrator and a voltage-current converter, wherein:

[0021] The first end of the hysteresis voltage comparator is connected to the second end of the inverting integrator, and the second end of the hysteresis voltage comparator 1 is connected to the control end of the first switch unit;

[0022] The first switch unit is connected between the first terminal of the sign circuit and the ground terminal;

[0023] The second terminal of the sign circuit is connected to the first terminal of the inverting integrator;

[0024] The second terminal of the inverting integrator is connected to the first terminal of the voltage-current converter;

[0025] The second end of the voltage-current converter is connected to the positive electrode of the battery and the first input end of the amplitude and phase detection module 1 respectively.

[0026] Optionally, the waveform generator further comprises a voltage reduction unit, wherein:

[0027] The second end of the inverting integrator is connected to the first end of the voltage-current converter through the voltage-step-down unit.

[0028] Optionally, the waveform generator further includes a current limiting unit, wherein:

[0029] The second end of the hysteresis voltage comparator is connected to the control end of the first switch unit through the current limiting unit.

[0030] Optionally, the hysteresis voltage comparator comprises: a first resistor, a second resistor, a third resistor, a fourth resistor, a first operational amplifier and a third diode, wherein:

[0031] The inverting input terminal of the first operational amplifier is connected to the second terminal of the inverting integrator, the non-inverting input terminal of the first operational amplifier is grounded through the second resistor, and the output terminal of the first operational amplifier is connected to the first terminal of the first resistor;

[0032] The third resistor is connected between the non-inverting input terminal of the first operational amplifier and the second end of the first resistor;

[0033] The fourth resistor is connected between the second end of the first resistor and the control end of the first switch unit;

[0034] An anode of the third diode is connected to the control end of the first switch unit, and a cathode of the third diode is grounded.

[0035] Optionally, the hysteresis voltage comparator further includes: a first diode and a second diode, wherein:

[0036] The second end of the first resistor is connected to the cathode of the first diode;

[0037] The anode of the first diode is connected to the anode of the second diode;

[0038] The cathode of the second diode is grounded;

[0039] Wherein, the first diode and the second diode are voltage stabilizing diodes.

[0040] Optionally, the symbol circuit includes: a fundamental wave generator, a sixth resistor, a seventh resistor, a second operational amplifier, an eighth resistor and a ninth resistor, wherein:

[0041] The fundamental wave generator is connected to the ground terminal and the first end of the sixth resistor;

[0042] The second end of the sixth resistor is connected to the first switch unit;

[0043] The seventh resistor is connected between the second end of the sixth resistor and the non-inverting input terminal of the second operational amplifier;

[0044] The eighth resistor is connected between the ground terminal and the inverting input terminal of the second operational amplifier;

[0045] The ninth resistor is connected between the inverting input terminal of the second operational amplifier and the output terminal of the second operational amplifier;

[0046] The output terminal of the second operational amplifier is connected to the first terminal of the inverting integrator.

[0047] Optionally, the fundamental wave generator is a square wave generator.

[0048] Optionally, the inverting integrator comprises: a tenth resistor, a first capacitor and a third operational amplifier, wherein:

[0049] The tenth resistor is connected between the second end of the sign circuit and the inverting input end of the third operational amplifier;

[0050] The non-inverting input terminal of the third operational amplifier is grounded, the output terminal of the third operational amplifier is connected to the second terminal of the sign circuit through the first capacitor C, and the output terminal of the third operational amplifier is connected to the voltage-current converter.

[0051] Optionally, the voltage-current converter includes: an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a fifteenth resistor and a fourth operational amplifier, wherein:

[0052] The eleventh resistor is connected between the non-inverting input terminal of the fourth operational amplifier and the ground terminal;

[0053] The twelfth resistor is connected between the output terminal of the fourth operational amplifier and the inverting input terminal of the fourth operational amplifier;

[0054] The thirteenth resistor and the fourteenth resistor are connected in series between the output terminal of the fourth operational amplifier and the ground terminal;

[0055] The fifteenth resistor is connected to the second end of the inverting integrator and the inverting input end of the fourth operational amplifier;

[0056] The non-inverting input terminal of the fourth operational amplifier is connected to the first intermediate point, wherein the first intermediate point is the connection point of the thirteenth resistor and the fourteenth resistor;

[0057] The first intermediate point is connected to the positive electrode of the battery.

[0058] Optionally, the voltage reduction unit includes: a first inductor, a fourth diode, a second capacitor and a second switch unit, wherein:

[0059] The second switch unit is connected between the second end of the inverting integrator and the first end of the first inductor, and the control end of the second switch unit is used to access the step-down control signal;

[0060] A cathode of the fourth diode is connected to the first end of the first inductor, and an anode of the fourth diode is grounded;

[0061] The second capacitor is connected between the second end of the first inductor and the ground end;

[0062] The second end of the first inductor is connected to the first end of the voltage-current converter.

[0063] Optionally, the current limiting unit is a fifth resistor.

[0064] Optionally, the voltage-current converter includes: an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a fifteenth resistor, a fourth operational amplifier and a fifth operational amplifier, wherein:

[0065] The eleventh resistor is connected to the second end of the inverting integrator and the non-inverting input end of the fourth operational amplifier;

[0066] The twelfth resistor is connected between the output terminal of the fourth operational amplifier and the inverting input terminal of the fourth operational amplifier;

[0067] The thirteenth resistor is connected between the output terminal of the fourth operational amplifier and the non-inverting input terminal of the fifth operational amplifier;

[0068] The fourteenth resistor is connected between the output terminal of the fifth operational amplifier and the non-inverting input terminal of the fourth operational amplifier;

[0069] The fifteenth resistor is connected between the inverting input terminal of the fourth operational amplifier and the ground terminal;

[0070] The inverting input terminal of the fifth operational amplifier is connected to the output terminal of the fifth operational amplifier, and the non-inverting input terminal of the fifth operational amplifier is connected to the positive electrode of the battery.

[0071] Optionally, it is characterized in that the voltage-current converter further includes: an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, a fourth operational amplifier and a fifth operational amplifier, wherein:

[0072] The eleventh resistor is connected to the second end of the inverting integrator and the non-inverting input end of the fourth operational amplifier;

[0073] The twelfth resistor is connected between the output terminal of the fourth operational amplifier and the inverting input terminal of the fourth operational amplifier;

[0074] The thirteenth resistor is connected between the output terminal of the fourth operational amplifier and the non-inverting input terminal of the fifth operational amplifier;

[0075] The fifteenth resistor is connected between the inverting input terminal of the fourth operational amplifier and the ground terminal;

[0076] The fourteenth resistor, the eighteenth resistor, and the sixteenth resistor are sequentially connected in series to the non-inverting input terminal of the fourth operational amplifier and the non-inverting input terminal of the fifth operational amplifier;

[0077] The seventeenth resistor is connected between the output terminal of the fourth operational amplifier and the second intermediate point, wherein the second intermediate point is the connection point between the fourteenth resistor and the eighteenth resistor;

[0078] The second intermediate point is connected to the positive electrode of the battery.

[0079] Optionally, the amplitude and phase detection module includes: an amplitude detection unit and a phase detection unit, wherein:

[0080] The first input terminal of the amplitude detection unit is connected to the output terminal of the waveform generator, and the second input terminal of the amplitude detection unit is connected to the positive electrode of the battery;

[0081] The first input end of the phase detection unit is connected to the output end of the waveform generator, and the second input end of the phase detection unit is connected to the positive electrode of the battery.

[0082] Optionally, the amplitude detection unit includes: a first detection circuit, a second detection circuit and a nineteenth resistor, wherein:

[0083] The first end of the first detection circuit is connected to the output end of the waveform generator;

[0084] The first end of the second detection circuit is connected to the positive electrode of the battery;

[0085] The nineteenth resistor is connected between the second end of the first detection circuit and the second end of the second detection circuit.

[0086] Optionally, the first detection circuit includes: a fifth diode, wherein:

[0087] An anode of the fifth diode is connected to the output end of the waveform generator, and a cathode of the fifth diode is connected to the nineteenth resistor.

[0088] Optionally, the first detection circuit further includes a first filtering circuit, wherein:

[0089] The first filtering circuit is connected between the cathode of the fifth diode and a ground terminal.

[0090] Optionally, the first filtering circuit comprises: a twenty-first resistor and a third capacitor, wherein:

[0091] The twenty-first resistor and the third capacitor are respectively connected in parallel between the cathode of the fifth diode and the ground terminal.

[0092] Optionally, the second detection circuit includes: a sixth diode, wherein:

[0093] The cathode of the sixth diode is connected to the positive electrode of the battery, and the anode of the sixth diode is connected to the nineteenth resistor.

[0094] Optionally, the second detection circuit further includes: a second filtering circuit, wherein:

[0095] The second filtering circuit is connected between the anode of the sixth diode and the ground terminal.

[0096] Optionally, the second filtering circuit includes: a twenty-second resistor and a fourth capacitor, wherein:

[0097] The twenty-second resistor and the fourth capacitor are connected in parallel between the anode of the sixth diode and the ground terminal, respectively.

[0098] Optionally, the phase detection unit includes: a third detection circuit, a fourth detection circuit, a twentieth resistor, an addition circuit and a subtraction circuit, wherein:

[0099] The first end of the adding circuit is connected to the output end of the waveform generator, and the second end of the adding circuit is connected to the positive electrode of the battery;

[0100] The first end of the third detection circuit is connected to the third end of the adding circuit;

[0101] The first end of the subtraction circuit is connected to the output end of the waveform generator, and the second end of the subtraction circuit is connected to the positive electrode of the battery;

[0102] The first end of the fourth detection circuit is connected to the third end of the subtraction circuit;

[0103] The twentieth resistor is connected between the second end of the third detection circuit and the second end of the fourth detection circuit.

[0104] Optionally, the third detection circuit includes: a seventh diode, wherein:

[0105] A cathode of the seventh diode is connected to the third end of the adding circuit, and an anode of the seventh diode is connected to the twentieth resistor.

[0106] Optionally, the third detection circuit further includes: a third filtering circuit, wherein:

[0107] The third filtering circuit is connected between the anode of the seventh diode and the ground terminal.

[0108] Optionally, the fourth detection circuit comprises: an eighth diode, wherein:

[0109] An anode of the eighth diode is connected to the third end of the subtraction circuit, and a cathode of the eighth diode is connected to the twentieth resistor.

[0110] Optionally, the fourth detection circuit further includes: a fourth filtering circuit, wherein:

[0111] The fourth filtering circuit is connected between the cathode of the eighth diode and the ground terminal.

[0112] Optionally, the adding circuit includes: a twenty-third resistor, a twenty-fourth resistor, a twenty-fifth resistor, a twenty-sixth resistor, a twenty-seventh resistor and a sixth operational amplifier, wherein:

[0113] The twenty-third resistor is connected between the ground terminal and the inverting input terminal of the sixth operational amplifier;

[0114] The twenty-fourth resistor is connected between the inverting input terminal of the sixth operational amplifier and the output terminal of the sixth operational amplifier;

[0115] The twenty-fifth resistor is connected between the output terminal of the waveform generator and the non-inverting input terminal of the sixth operational amplifier;

[0116] The twenty-sixth resistor is connected between the positive electrode of the battery and the non-inverting input terminal of the sixth operational amplifier;

[0117] The twenty-seventh resistor is connected between the non-inverting input terminal of the sixth operational amplifier and the ground terminal;

[0118] The output end of the sixth operational amplifier is connected to the first end of the third detection circuit.

[0119] Optionally, the subtraction circuit includes: a twenty-eighth resistor, a twenty-ninth resistor, a thirtieth resistor, a thirty-first resistor and a seventh operational amplifier, wherein:

[0120] The twenty-eight resistors are connected between the inverting input terminal of the seventh operational amplifier and the output terminal of the seventh operational amplifier;

[0121] The output end of the seventh operational amplifier is connected to the first end of the fourth detection circuit;

[0122] The twenty-ninth resistor is connected between the inverting input terminal of the seventh operational amplifier and the output terminal of the waveform generator;

[0123] The 30th resistor is connected between the non-inverting input of the seventh operational amplifier and the positive electrode of the battery;

[0124] The thirty-first resistor is connected between the non-inverting input terminal of the seventh operational amplifier and the ground terminal.

[0125] According to a second aspect of the present application, a battery management chip is provided, wherein the battery management chip comprises a battery management circuit as described in any one of the first aspects.

[0126] According to a third aspect of the present application, a vehicle is provided, comprising the battery management chip as described in the second aspect.

[0127] The present application provides a battery management circuit, including: an amplitude-phase detection module and a waveform generator, wherein: the output end of the waveform generator is respectively connected to the positive electrode of the battery and the first input end of the amplitude-phase detection module; the second input end of the amplitude-phase detection module is connected to the positive electrode of the battery; wherein the waveform generator is used to apply AC excitation signals of different frequencies to the battery, and the amplitude-phase detection module is used to detect the amplitude and phase of the impedance of the battery under AC excitation signals of different frequencies. That is, the present application provides a battery management circuit, which is a new battery management system that can estimate the battery power and life, and can better characterize the kinetic information in the electrode process and the conductivity of the battery material compared to general voltage and current data.

[0128] Other features and advantages of the present application will become apparent from the following detailed description of exemplary embodiments of the present application with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0129] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the application and, together with the description, serve to explain the principles of the application.

[0130] Figure 1 This is a schematic diagram of a battery management circuit provided by this application. Figure 1 ;

[0131] Figure 2 This is a schematic diagram of a battery management circuit provided by this application. Figure 2 ;

[0132] Figure 3 This is a schematic diagram of a battery management circuit provided by this application. Figure 3 ;

[0133] Figure 4 This is a schematic diagram of a battery management circuit provided by this application. Figure 3 ;

[0134] Figure 5 This is a schematic diagram of the structure of a waveform generator provided by this application. Figure 1 ;

[0135] Figure 6 This is a schematic diagram of the structure of a waveform generator provided by this application. Figure 2 ;

[0136] Figure 7 This is a schematic diagram of the structure of a waveform generator provided by this application. Figure 3 ;

[0137] Figure 8 This is a schematic diagram of the structure of a waveform generator provided by this application. Figure 4 ;

[0138] Fig. 9 This is a schematic diagram of the structure of a waveform generator provided by this application. Figure 5 ;

[0139] Fig.10 It is a structural schematic diagram of an amplitude and phase detection module provided by the present application;

[0140] Fig.11 It is a structural schematic diagram of an amplitude detection unit provided by the present application;

[0141] Fig.12 It is a structural schematic diagram of a phase detection unit provided in this application. DETAILED DESCRIPTION

[0142] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application.

[0143] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present application, its application, or uses.

[0144] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0145] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0146] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0147] The present application provides a battery management circuit, such as Figure 1 As shown, the battery management circuit includes: an amplitude and phase detection module 1 and a waveform generator 2, wherein:

[0148] The output end of the waveform generator 2 is connected to the positive electrode of the battery and the first input end of the amplitude and phase detection module 1 respectively;

[0149] The second input terminal of the amplitude and phase detection module 1 is connected to the positive electrode of the battery;

[0150] The waveform generator 2 is used to apply AC excitation signals of different frequencies to the battery, and the amplitude and phase detection module 1 is used to detect the amplitude and phase of the impedance of the battery under the AC excitation signals of different frequencies.

[0151] In the present application, an amplitude and phase detection module 1 and a waveform generator 2 are integrated in the battery management circuit. Among them, the waveform generator 2 provides AC excitation signals of different frequencies to the battery. The battery generates voltage disturbances under the excitation of the AC excitation signal input by the waveform generator 2. The amplitude and phase detection module 1 detects the voltage and current disturbances at both ends of the battery, and obtains the amplitude and phase of the impedance of the battery under different AC excitation signals in combination with the AC excitation signals of different frequencies input by the waveform generator 2.

[0152] Since the battery is not a pure resistance element, it exhibits capacitance or inductance during actual use, so its impedance expression consists of two parts: amplitude and phase. On this basis, the impedance spectrum of the battery can be determined by obtaining the amplitude and phase of the impedance of the battery under different AC excitation signals.

[0153] Since the impedance spectrum of the battery is an important parameter reflecting the battery performance, and can also be used as an effective parameter to judge and influence the battery charging and discharging performance to accurately reflect the working state of the battery, the impedance spectrum of the battery can provide a basis for evaluating the battery's power and life. In addition, the impedance spectrum can also reflect the radius of the active sub-electrodes of the positive and negative electrodes, the volume fraction of the positive and negative electrode electrolytes, the aging state of the positive and negative electrode liquid phase conductivity, the ohmic internal resistance, the SEI film impedance, the charge transfer internal resistance, and the diffusion impedance value of lithium electrons. That is to say, the present application provides a battery management circuit, which is a new battery management system that can estimate the battery power and life, and compared with general voltage and current data, it can better characterize the kinetic information in the electrode process and the conductivity of the battery material.

[0154] It should be noted that when the battery management circuit provided in the present application is working, the negative electrode of the battery usually needs to be grounded (in the chip, the grounding is specifically connected to a reference voltage).

[0155] The present application provides a battery management circuit, including: an amplitude-phase detection module and a waveform generator, wherein: the output end of the waveform generator is respectively connected to the positive electrode of the battery and the first input end of the amplitude-phase detection module; the second input end of the amplitude-phase detection module is connected to the positive electrode of the battery; wherein the waveform generator is used to apply AC excitation signals of different frequencies to the battery, and the amplitude-phase detection module is used to detect the amplitude and phase of the impedance of the battery under AC excitation signals of different frequencies. That is, the present application provides a battery management circuit, which is a new battery management system that can estimate the battery power and life, and can better characterize the kinetic information in the electrode process and the conductivity of the battery material compared to general voltage and current data.

[0156] In one embodiment of the present application, the AC excitation signals of different frequencies are swept frequency triangle wave signals of 0.01 Hz to 500 KHz.

[0157] In the present application, a broadband triangular wave signal is used as an AC excitation signal, so that a multi-frequency impedance spectrum test can be achieved in one measurement. On this basis, the working time of the battery management circuit provided in the present application can be greatly reduced, and the amplitude and phase detection of the impedance of the battery under different AC excitation signals can be quickly completed. In addition, since the frequency of the triangular wave signal changes slowly, the distortion of the signal can be minimized. In addition, when the amplitude and phase detected by the amplitude and phase detection module 1 are used for subsequent impedance calculations, each data sequence contains information such as frequency, phase and amplitude. The single-frequency triangular wave can be Fourier transformed to extract its five odd-multiple frequency signal points under the requirement of calculation accuracy. This not only reduces the frequency sweep time, but the subsequent digital signal processing also increases the accuracy of impedance calculations.

[0158] In one embodiment of the present application, Figure 2 As shown, the battery management circuit provided by the present application also includes: an analog-to-digital conversion module 3, a storage module 4 and a communication module 5, wherein:

[0159] The amplitude and phase detection module 1, the analog-to-digital conversion module 3, the storage module 4 and the communication module 5 are connected in sequence.

[0160] In the present application, the analog-to-digital conversion module 3 is responsible for converting the signal output by the amplitude-phase detection module 1, which reflects the amplitude and phase of the impedance of the battery under different AC excitation signals, from an analog signal to a digital signal to obtain a conversion result. The storage module 4 stores the conversion result for data communication of the conversion result by the communication module 5.

[0161] In the present application, the battery management circuit includes an analog-to-digital conversion module, a storage module and a communication module. In this way, the battery management circuit provided by the present application can present the data of the amplitude and phase detection module to the outside.

[0162] In one embodiment of the present application, Figure 3 As shown, the battery management circuit provided by the present application also includes a filtering module 6, wherein:

[0163] The analog-to-digital conversion module 3 is connected to the storage module 4 via the filter module 6 .

[0164] In the present application, a filter module is provided in the battery management circuit, and the filter module can filter out invalid signals in the digital signal output by the analog-to-digital conversion module to retain useful signals.

[0165] In one embodiment of the present application, Figure 4 As shown, the battery management circuit provided by the present application further includes: at least one of a voltage acquisition module 7, a current acquisition module 8, a temperature acquisition module 9, and a multiplexer 10, wherein:

[0166] The voltage acquisition module 7 is connected to the positive electrode of the battery, the negative electrode of the battery and the multiplexer 10 respectively;

[0167] The current acquisition module 8 is connected to the positive electrode of the battery or the negative electrode of the battery, and the current acquisition module 8 is connected to the multiplexer 10;

[0168] The temperature acquisition module 9 is connected to the multiplexer 10;

[0169] The amplitude and phase detection module 1 is connected to the multiplexer 10;

[0170] The multiplexer 10 is connected to the input end of the analog-to-digital conversion module 3 .

[0171] In the present application, a voltage acquisition module 7, a current acquisition module 8 and a temperature acquisition module 9 are provided in the battery management circuit. The voltage acquisition module 7 completes the battery voltage acquisition, the current acquisition module 8 completes the battery current acquisition, and the temperature acquisition module 9 completes the battery temperature acquisition. Furthermore, the multiplexer transmits one signal to the back-end circuit.

[0172] Based on the battery management circuit provided in this embodiment, the voltage, current and temperature of the battery can be detected.

[0173] In one embodiment of the present application, Figure 5 As shown, the waveform generator 2 includes: a hysteresis voltage comparator 21, a first switch unit 22, a sign circuit 23, an inverting integrator 24 and a voltage-current converter 25, wherein:

[0174] A first end of the hysteresis voltage comparator 21 is connected to a second end of the inverting integrator 24, and a second end of the hysteresis voltage comparator 21 is connected to a control end of the first switch unit 22;

[0175] The first switch unit 22 is connected between the first terminal of the sign circuit 23 and the ground terminal;

[0176] The second terminal of the sign circuit 23 is connected to the first terminal of the inverting integrator 24;

[0177] The second end of the inverting integrator 24 is connected to the first end of the voltage-current converter 25;

[0178] The second end of the voltage-current converter 25 is connected to the positive electrode of the battery and the first input end of the amplitude and phase detection module 1 respectively.

[0179] In the present application, the hysteresis voltage comparator 21 outputs a square wave signal with a certain threshold. The square wave signal controls the first switch unit 22 so that the output signal of the sign circuit 23 is proportionally amplified with the input signal. The inverting integrator 24 integrates and inverts the signal output by the sign circuit 23. In this way, the frequency change of the triangular wave signal can be achieved. By changing the voltage amplitude of the input signal of the sign circuit 23, the periodic sweep signal input can be completed, the oscillation process can be completed, and then a stable triangular wave signal with a certain frequency can be output. Furthermore, since the battery is a low-resistance energy storage device, a slight error in applying voltage to the battery will cause a huge current change in the battery. Therefore, a voltage-current converter 25 is added to the second end of the inverting integrator 24.

[0180] In one embodiment of the present application, based on Figure 5 The waveform generator 2 shown is Figure 6 As shown, the waveform generator 2 further includes a voltage reduction unit 26, wherein:

[0181] A second terminal of the inverting integrator 24 is connected to a first terminal of the voltage-current converter 25 via a voltage-drop unit 26 .

[0182] In the present application, the battery management circuit provided by the present application is implemented based on an AC signal, and the AC excitation signal input to the battery cannot be too large, otherwise it is easy to cause damage to the internal structure of the system. Therefore, a step-down unit 26 is introduced to perform step-down AC modulation on the output signal of the inverting integrator 24.

[0183] In one embodiment of the present application, Figure 6 As shown, the waveform generator 2 further includes a current limiting unit 27, wherein:

[0184] The second terminal of the hysteresis voltage comparator 21 is connected to the control terminal of the first switch unit 22 through the current limiting unit 27 .

[0185] In one example, the current limiting unit can be exemplarily a resistor, that is, Figure 7 The fifth resistor is shown.

[0186] In the present application, the current limiting unit 27 is used to limit the amplitude of the control signal input to the control end of the first switch unit 22, so as to protect the first switch unit 22 from being damaged and improve the reliability of the first switch unit 22.

[0187] In one embodiment of the present application, Figure 7 , Figures 8 to 9 As shown in any one of the above, the hysteresis voltage comparator 21 includes: a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a first operational amplifier U1 and a third diode D3, wherein:

[0188] The inverting input terminal of the first operational amplifier U1 is connected to the second terminal of the inverting integrator 24, the non-inverting input terminal of the first operational amplifier U1 is grounded through the second resistor R2, and the output terminal of the first operational amplifier U1 is connected to the first terminal of the first resistor R1;

[0189] The third resistor R3 is connected between the non-inverting input terminal of the first operational amplifier U1 and the second end of the first resistor R1;

[0190] The fourth resistor R4 is connected between the second end of the first resistor R1 and the control end of the first switch unit 22;

[0191] An anode of the third diode D3 is connected to the control end of the first switch unit 22 , and a cathode of the third diode D3 is grounded.

[0192] The present application provides a structure of a hysteresis voltage comparator. It is understandable that in the battery management circuit provided by the present application, the hysteresis voltage comparator can also be implemented using other structures, which is not limited by the present application.

[0193] In one embodiment of the present application, Figure 7 , Figures 8 to 9 As shown in any one of the above, the hysteresis voltage comparator 21 further includes: a first diode D1 and a second diode D2, wherein:

[0194] The second end of the first resistor R1 is connected to the cathode of the first diode D1;

[0195] The anode D1 of the first diode is connected to the anode of the second diode D2;

[0196] The cathode of the second diode D2 is grounded;

[0197] The first diode D1 and the second diode D2 are voltage-stabilizing diodes.

[0198] In the present application, the first diode D1 and the second diode D2 form a voltage stabilizer, so that the hysteresis voltage comparator 21 outputs a square wave signal of a stable voltage.

[0199] In one embodiment of the present application, Figure 7 , Figures 8 to 9 As shown in any one of the above, the symbol circuit 23 includes: a fundamental wave generator W, a sixth resistor R6, a seventh resistor R7, a second operational amplifier U2, an eighth resistor R8 and a ninth resistor R9, wherein:

[0200] The fundamental wave generator W is connected to the ground terminal and the first end of the sixth resistor R6;

[0201] The second end of the sixth resistor R6 is connected to the first switch unit 22;

[0202] The seventh resistor R7 is connected between the second end of the sixth resistor R6 and the non-inverting input end of the second operational amplifier U2;

[0203] The eighth resistor R8 is connected between the ground terminal and the inverting input terminal of the second operational amplifier U2;

[0204] The ninth resistor R9 is connected between the inverting input terminal of the second operational amplifier U2 and the output terminal of the second operational amplifier U2;

[0205] The output terminal of the second operational amplifier U2 is connected to the first terminal of the inverting integrator 24 .

[0206] The present application provides a structure of a symbol circuit. It is understandable that in the battery management circuit provided by the present application, the symbol circuit can also be implemented using other structures, which is not limited by the present application.

[0207] In one embodiment of the present application, Figure 7 , Figures 8 to 9 As shown in any one of the above embodiments, the fundamental wave generator W in the above embodiments is a square wave generator.

[0208] In one embodiment of the present application, Figure 7 , Figures 8 to 9 As shown in any one of the above, the inverting integrator 24 includes: a tenth resistor R10, a first capacitor C and a third operational amplifier U3, wherein:

[0209] The tenth resistor R10 is connected between the second end of the sign circuit 23 and the inverting input end of the third operational amplifier U3;

[0210] The non-inverting input terminal of the third operational amplifier U3 is grounded, the output terminal of the third operational amplifier U3 is connected to the second terminal of the sign circuit 23 through the first capacitor C1 , and the output terminal of the third operational amplifier U3 is connected to the voltage-current converter 25 .

[0211] The present application provides a structure of an inverting integrator 24. It is understandable that in the battery management circuit provided by the present application, the inverting integrator 24 can also be implemented by other structures, which is not limited by the present application.

[0212] In one embodiment of the present application, Figure 7 As shown, the voltage-current converter 25 includes: an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15 and a fourth operational amplifier U4, wherein:

[0213] The eleventh resistor R11 is connected between the non-inverting input terminal of the fourth operational amplifier U4 and the ground terminal;

[0214] The twelfth resistor R12 is connected between the output terminal of the fourth operational amplifier U4 and the inverting input terminal of the fourth operational amplifier U4;

[0215] A thirteenth resistor R13 and a fourteenth resistor R14 are connected in series and connected between the output terminal of the fourth operational amplifier U4 and the ground terminal;

[0216] A fifteenth resistor R15 is connected between the second end of the inverting integrator 24 and the inverting input end of the fourth operational amplifier U4;

[0217] The non-inverting input terminal of the fourth operational amplifier U4 is connected to the first middle point M, wherein the first middle point M is the connection point of the thirteenth resistor R13 and the fourteenth resistor R14;

[0218] The first middle point M is connected to the positive electrode of the battery.

[0219] The present application provides a structure of a voltage-current converter 25. It is understandable that in the battery management circuit provided by the present application, the voltage-current converter 25 can also be implemented by other structures, which is not limited by the present application.

[0220] In one embodiment of the present application, Figure 7 , Figures 8 to 9 As shown in any one of the above, the voltage reduction unit 26 includes: a first inductor L1, a fourth diode D4, a second capacitor C2 and a second switch unit Q2, wherein:

[0221] The second switch unit Q2 is connected between the second end of the inverting integrator 24 and the first end of the first inductor L1, and the control end of the second switch unit Q2 is used to access the step-down control signal;

[0222] A cathode of the fourth diode D4 is connected to the first end of the first inductor L1, and an anode of the fourth diode D4 is grounded;

[0223] The second capacitor C2 is connected between the second end of the first inductor L1 and the ground end;

[0224] A second end of the first inductor L1 is connected to a first end of the voltage-to-current converter 25 .

[0225] The present application provides a structure of a voltage reduction unit 26. It is understandable that in the battery management circuit provided by the present application, the voltage reduction unit 26 can also be implemented by other structures, which is not limited by the present application.

[0226] In one embodiment of the present application, Figure 8 As shown, the voltage-current converter 25 includes: an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15, a fourth operational amplifier U4 and a fifth operational amplifier U5, wherein:

[0227] The eleventh resistor R11 is connected to the second end of the inverting integrator 24 and the non-inverting input end of the fourth operational amplifier U4;

[0228] The twelfth resistor R12 is connected between the output terminal of the fourth operational amplifier U4 and the inverting input terminal of the fourth operational amplifier U4;

[0229] The thirteenth resistor R13 is connected between the output terminal of the fourth operational amplifier U4 and the non-inverting input terminal of the fifth operational amplifier U5;

[0230] The fourteenth resistor R14 is connected between the output terminal of the fifth operational amplifier U5 and the non-inverting input terminal of the fourth operational amplifier;

[0231] A fifteenth resistor R15 is connected between the inverting input terminal of the fourth operational amplifier U4 and the ground terminal;

[0232] The inverting input terminal of the fifth operational amplifier U5 is connected to the output terminal of the fifth operational amplifier U5, and the non-inverting input terminal of the fifth operational amplifier U5 is connected to the positive electrode of the battery.

[0233] In this application, Figure 8 The structure of the voltage-current converter 25 shown is compared with the Figure 7 The structure of the voltage-current converter 25 shown is different in that a fifth operational amplifier U5 is additionally used. Thus, the fifth operational amplifier U5 forms a voltage follower circuit, so that the input and output of the voltage-current converter 25 are in phase. On this basis, the distortion of the output current signal of the voltage-current converter 25 can be reduced, and the noise suppression capability can be improved.

[0234] In one embodiment of the present application, Fig. 9 As shown, the voltage-current converter 25 further includes: an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15, a sixteenth resistor R16, a seventeenth resistor R17, an eighteenth resistor R18, a fourth operational amplifier U4 and a fifth operational amplifier U5, wherein:

[0235] The eleventh resistor R11 is connected to the second end of the inverting integrator 24 and the non-inverting input end of the fourth operational amplifier U4;

[0236] The twelfth resistor R12 is connected between the output terminal of the fourth operational amplifier U4 and the inverting input terminal of the fourth operational amplifier U4;

[0237] The thirteenth resistor R13 is connected between the output terminal of the fourth operational amplifier U4 and the non-inverting input terminal of the fifth operational amplifier U5;

[0238] A fifteenth resistor R15 is connected between the inverting input terminal of the fourth operational amplifier U4 and the ground terminal;

[0239] A fourteenth resistor R14, an eighteenth resistor R18, and a sixteenth resistor R16 are sequentially connected in series to the non-inverting input terminal of the fourth operational amplifier U4 and the non-inverting input terminal of the fifth operational amplifier U5;

[0240] The seventeenth resistor R17 is connected between the output terminal of the fourth operational amplifier U4 and the second middle point N, wherein the second middle point N is the connection point between the fourteenth resistor R14 and the eighteenth resistor R18;

[0241] The second intermediate point N is connected to the positive electrode of the battery.

[0242] In this application, Fig. 9 The structure of the voltage-current converter 25 shown is compared with the Figure 7 The structure of the voltage-current converter 25 shown is different in that a fifth operational amplifier U5 is additionally used. Thus, a bridge differential excitation structure is formed by the fifth operational amplifier U5. Thus, the output signals of the voltage-current converter 25 can maintain an approximately linear correlation, so that the output current of the voltage-current converter 25 is less affected by the change in the amplitude of the input signal and has a better constant current characteristic.

[0243] In one embodiment of the present application, Figure 1 As shown, the amplitude and phase detection module 1 includes: an amplitude detection unit 11 and a phase detection unit 12, wherein:

[0244] The first input terminal of the amplitude detection unit 11 is connected to the output terminal of the waveform generator 2, and the second input terminal of the amplitude detection unit 11 is connected to the positive electrode of the battery;

[0245] A first input terminal of the phase detection unit 12 is connected to the output terminal of the waveform generator 2 , and a second input terminal of the phase detection unit 12 is connected to the positive electrode of the battery.

[0246] In the present application, the amplitude and phase detection module 1 is specifically implemented by an amplitude detection unit 11 and a phase detection unit 12. The amplitude detection module 11 is used to detect the amplitude of the impedance of the battery under AC excitation signals of different frequencies. The phase detection unit 12 is used to detect the phase of the impedance of the battery under AC excitation signals of different frequencies.

[0247] In one embodiment of the present application, Fig.10 As shown, the amplitude detection unit 11 includes: a first detection circuit 111, a second detection circuit 112 and a nineteenth resistor R19, wherein:

[0248] A first end of the first detection circuit 111 is connected to an output end of the waveform generator 2;

[0249] A first terminal of the second detection circuit 112 is connected to the positive electrode of the battery;

[0250] The nineteenth resistor R19 is connected between the second end of the first detection circuit 111 and the second end of the second detection circuit 112 .

[0251] The present application provides a structure of an amplitude detection unit 11. It is understandable that in the battery management circuit provided by the present application, the amplitude detection unit 11 can also be implemented by other structures, which is not limited by the present application.

[0252] In one embodiment of the present application, Fig.11 As shown, the first detection circuit 111 includes: a fifth diode D5, wherein:

[0253] An anode of the fifth diode D5 is connected to the output end of the waveform generator 2 , and a cathode of the fifth diode D5 is connected to the nineteenth resistor R19 .

[0254] The present application provides a structure of a first detection circuit 111. It is understandable that in the battery management circuit provided by the present application, the first detection circuit 111 may also be implemented using other structures, which is not limited by the present application.

[0255] In one embodiment of the present application, Fig.11 As shown, the first detection circuit 111 further includes a first filtering circuit 1111, wherein:

[0256] The first filter circuit 1111 is connected between the cathode of the fifth diode D5 and the ground terminal.

[0257] In the present application, adding the first filter circuit 1111 to the first detection circuit 111 can enable the first detection circuit 111 to perform more accurate detection.

[0258] In one embodiment of the present application, Fig.11 As shown, the first filtering circuit 1111 includes: a twenty-first resistor R21 and a third capacitor C3, wherein:

[0259] The twenty-first resistor R21 and the third capacitor C3 are connected in parallel between the cathode of the fifth diode D5 and the ground terminal, respectively.

[0260] The present application provides a structure of a first filter circuit 1111, and the first filter circuit 1111 is specifically an RC filter. It is understandable that in the battery management circuit provided by the present application, the first filter circuit 1111 can also be implemented by other structures, which is not limited by the present application.

[0261] In one embodiment of the present application, Fig.11 As shown, the second detection circuit 112 includes: a sixth diode D6, wherein:

[0262] The cathode of the sixth diode D6 is connected to the positive electrode of the battery, and the anode of the sixth diode D6 is connected to the nineteenth resistor R19.

[0263] The present application provides a structure of the second detection circuit 112. It is understandable that in the battery management circuit provided by the present application, the second detection circuit 112 can also be implemented by other structures, which is not limited by the present application.

[0264] In one embodiment of the present application, Fig.11 As shown, the second detection circuit 112 further includes: a second filtering circuit 1121, wherein:

[0265] The second filter circuit 1121 is connected between the anode of the sixth diode D6 and the ground terminal.

[0266] In the present application, adding the second filter circuit 1121 to the second detection circuit 112 can enable the second detection circuit 112 to perform more accurate detection.

[0267] In one embodiment of the present application, Fig.11 As shown, the second filtering circuit 1121 includes: a twenty-second resistor R22 and a fourth capacitor C4, wherein:

[0268] The twenty-second resistor R22 and the fourth capacitor C4 are connected in parallel between the anode of the sixth diode D6 and the ground terminal, respectively.

[0269] The present application provides a structure of a second filter circuit 1121, which is specifically an RC filter. It is understandable that in the battery management circuit provided by the present application, the second filter circuit 1121 can also be implemented using other structures, which is not limited by the present application.

[0270] On the basis of the above content, Fig.11 As an example, the working principle of the amplitude detection unit 11 is explained.

[0271] First, the AC excitation signal output by the waveform generator Denoted as:

[0272]

[0273] Among them, U I1 ,ω and The AC excitation signals are amplitude, frequency and phase.

[0274] Output signal from the positive terminal of the battery Denoted as:

[0275]

[0276] Among them, U I2 ,ω and The output signals are respectively output from the positive electrode of the battery amplitude, frequency and phase.

[0277] On this basis, the current of the first detection circuit for:

[0278]

[0279] in, is the voltage across the fifth diode D5.

[0280] The current of the second detection circuit for:

[0281]

[0282] in, is the voltage across the sixth diode D6.

[0283] Based on the above content, in the case of including the first filtering circuit and the second filtering circuit, it can be obtained:

[0284]

[0285] in, is the voltage across the twenty-first resistor R21.

[0286]

[0287] in, is the voltage across the twenty-second resistor R22.

[0288]

[0289] Without including the first filtering circuit and the second filtering circuit, it can be obtained:

[0290]

[0291] Based on the above formula, we can know that by constructing Fig.11 The amplitude detection unit shown in FIG. 1 can obtain the impedance amplitude U of the battery based on the above formula 7 or formula 8. MAG .

[0292] It should be noted that a, b, and c in the above formula are parameters of the corresponding diodes and have fixed values.

[0293] In one embodiment of the present application, Fig.10As shown, the phase detection unit 12 includes: a third detection circuit 122, a fourth detection circuit 123, a twentieth resistor R20, an addition circuit 121 and a subtraction circuit 124, wherein:

[0294] A first end of the adding circuit 121 is connected to the output end of the waveform generator 2, and a second end of the adding circuit 121 is connected to the positive electrode of the battery;

[0295] A first terminal of the third detection circuit 122 is connected to a third terminal of the adding circuit 121;

[0296] A first terminal of the subtraction circuit 124 is connected to the output terminal of the waveform generator 2, and a second terminal of the subtraction circuit 124 is connected to the positive electrode of the battery;

[0297] A first terminal of the fourth detection circuit 123 is connected to a third terminal of the subtraction circuit 124;

[0298] The twentieth resistor R20 is connected between the second end of the third detection circuit 122 and the second end of the fourth detection circuit 123 .

[0299] The present application provides a structure of a phase detection unit 12. It is understandable that in the battery management circuit provided by the present application, the phase detection unit 12 can also be implemented by other structures, which is not limited by the present application.

[0300] In one embodiment of the present application, Fig.12 , the third detection circuit 122 includes: a seventh diode D7, wherein:

[0301] A cathode of the seventh diode D7 is connected to the third end of the adding circuit 121 , and an anode of the seventh diode D7 is connected to the twentieth resistor R20 .

[0302] The present application provides a structure of the third detection circuit 122. It is understandable that in the battery management circuit provided by the present application, the third detection circuit 122 can also be implemented by other structures, which is not limited by the present application.

[0303] In one embodiment of the present application, Fig.12 The third detection circuit 122 further includes: a third filtering circuit 1221, wherein:

[0304] The third filtering circuit 1221 is connected between the anode of the seventh diode D7 and the ground terminal.

[0305] In the present application, adding the third filter circuit 1221 to the third detection circuit 122 can enable the third detection circuit 122 to perform more accurate detection.

[0306] In one embodiment of the present application, Fig.12As shown, the third filtering circuit 1221 includes: a thirty-second resistor R32 and a fifth capacitor C5, wherein:

[0307] The thirty-second resistor R32 and the fifth capacitor C5 are respectively connected in parallel between the anode of the seventh diode D7 and the ground terminal.

[0308] The present application provides a structure of a third filter circuit 1221, and the third filter circuit 1221 is specifically an RC filter. It is understandable that in the battery management circuit provided by the present application, the third filter circuit 1221 can also be implemented by other structures, and the present application does not limit this.

[0309] In one embodiment of the present application, Fig.12 , the fourth detection circuit 123 comprises: an eighth diode D8, wherein:

[0310] An anode of the eighth diode D8 is connected to the third end of the subtraction circuit 124 , and a cathode of the eighth diode D8 is connected to the twentieth resistor R20 .

[0311] The present application provides a structure of the fourth detection circuit 123. It is understandable that in the battery management circuit provided by the present application, the fourth detection circuit 123 can also be implemented by other structures, which is not limited by the present application.

[0312] In one embodiment of the present application, Fig.12 The fourth detection circuit 123 further includes: a fourth filtering circuit 1231, wherein:

[0313] The fourth filtering circuit 1231 is connected between the cathode of the eighth diode R20 and the ground terminal.

[0314] In the present application, adding the fourth filter circuit 1231 to the fourth detection circuit 123 can enable the fourth detection circuit 123 to perform more accurate detection.

[0315] In one embodiment of the present application, Fig.12 As shown, the fourth detection circuit 123 includes: a thirty-third resistor R33 and a fifth capacitor C6, wherein:

[0316] The thirty-second resistor R33 and the fifth capacitor C6 are connected in parallel between the cathode of the eighth diode D8 and the ground terminal, respectively.

[0317] The present application provides a structure of a fourth detection circuit 123, which is specifically an RC filter. It is understandable that in the battery management circuit provided by the present application, the fourth detection circuit 123 can also be implemented using other structures, which is not limited by the present application.

[0318] On the basis of the above content, Fig.12Take as an example to illustrate the working principle of the phase detection unit 11.

[0319] The current of the third detection circuit for:

[0320]

[0321] in, is the voltage across the seventh diode D7.

[0322] Current of the fourth detection circuit for:

[0323]

[0324] in, is the voltage across the eighth diode D8.

[0325] Based on the above content, in the case of including the third filter circuit and the fourth filter circuit, it can be obtained:

[0326]

[0327] in, is the voltage across the thirty-third resistor R33.

[0328]

[0329] in, is the voltage across the thirty-second resistor R32.

[0330]

[0331] Without including the third filtering circuit and the fourth filtering circuit, it can be obtained:

[0332]

[0333] Based on the above formula, we can know that by constructing Fig.12 The phase detection unit shown in FIG. 14 can obtain the phase U of the battery impedance based on the above formula 14 or formula 13. phase .

[0334] In one embodiment of the present application, Fig.12 The adding circuit 121 includes: a twenty-third resistor R23, a twenty-fourth resistor R24, a twenty-fifth resistor R25, a twenty-sixth resistor R26, a twenty-seventh resistor R27 and a sixth operational amplifier U6, wherein:

[0335] A twenty-third resistor R23 is connected between the ground terminal and the inverting input terminal of the sixth operational amplifier U6;

[0336] A twenty-fourth resistor R24 ​​is connected between the inverting input terminal of the sixth operational amplifier U6 and the output terminal of the sixth operational amplifier;

[0337] A twenty-fifth resistor R25 is connected between the output terminal of the waveform generator 2 and the non-inverting input terminal of the sixth operational amplifier U6;

[0338] A twenty-sixth resistor R26 is connected between the positive electrode of the battery and the non-inverting input terminal of the sixth operational amplifier U6;

[0339] The twenty-seventh resistor R27 is connected between the non-inverting input terminal of the sixth operational amplifier U6 and the ground terminal;

[0340] The output terminal of the sixth operational amplifier U6 is connected to the first terminal of the third detection circuit 122 .

[0341] The present application provides a structure of an adding circuit 121. It is understandable that in the battery management circuit provided by the present application, the adding circuit 121 can also be implemented by other structures, which is not limited by the present application.

[0342] In one embodiment of the present application, Fig.12 The subtraction circuit 124 includes: a twenty-eighth resistor R28, a twenty-ninth resistor R29, a thirtieth resistor R30, a thirty-first resistor R31 and a seventh operational amplifier U7, wherein:

[0343] The twenty-eighth resistor R28 is connected between the inverting input terminal of the seventh operational amplifier U7 and the output terminal of the seventh operational amplifier U7;

[0344] The output terminal of the seventh operational amplifier U7 is connected to the first terminal of the fourth detection circuit 123;

[0345] A twenty-ninth resistor R29 is connected between the inverting input terminal of the seventh operational amplifier U7 and the output terminal of the waveform generator 2;

[0346] The 30th resistor R30 is connected between the non-inverting input of the seventh operational amplifier U7 and the positive electrode of the battery;

[0347] The thirty-first resistor R31 is connected between the non-inverting input terminal of the seventh operational amplifier U7 and the ground terminal.

[0348] The present application provides a structure of a subtraction circuit 124. It is understandable that in the battery management circuit provided by the present application, the subtraction circuit 124 can also be implemented by other structures, which is not limited by the present application.

[0349] The present application also provides a battery management chip, and a battery management circuit provided by any of the above embodiments of the battery management chip.

[0350] The present application also provides a vehicle, which includes the battery management chip provided in the above embodiment.

[0351] The embodiments of the present application have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein. The scope of the present application is defined by the appended claims.

Claims

1. A battery management circuit, characterized in that: include: An amplitude and phase detection module (1) and a waveform generator (2), wherein: The output end of the waveform generator (2) is connected to the positive electrode of the battery and the first input end of the amplitude and phase detection module (1) respectively; The second input end of the amplitude and phase detection module (1) is connected to the positive electrode of the battery; The waveform generator (2) is used to apply AC excitation signals of different frequencies to the battery, and the amplitude and phase detection module (1) is used to detect the amplitude and phase of the impedance of the battery under the AC excitation signals of different frequencies.

2. The battery management circuit according to claim 1, characterized in that: The AC excitation signals of different frequencies are swept frequency triangle wave signals of 0.01 Hz to 500 KHz.

3. The battery management circuit according to claim 1, characterized in that: The battery management circuit further comprises: an analog-to-digital conversion module (3), a storage module (4) and a communication module (5), wherein: The amplitude and phase detection module (1), the analog-to-digital conversion module (3), the storage module (4) and the communication module (5) are connected in sequence.

4. The battery management circuit according to claim 3, characterized in that: The battery management circuit further comprises a filter module (6), wherein: The analog-to-digital conversion module (3) is connected to the storage module (4) via the filtering module (6).

5. The battery management circuit according to claim 3 or 4, characterized in that: The battery management circuit further comprises: at least one of a voltage acquisition module (7), a current acquisition module (8), a temperature acquisition module (9) and a multiplexer (10), wherein: The voltage acquisition module (7) is respectively connected to the positive electrode of the battery, the negative electrode of the battery and the multiplexer (10); The current acquisition module (8) is connected to the positive electrode of the battery or the negative electrode of the battery, and the current acquisition module (8) is connected to the multiplexer (10); The temperature acquisition module (9) is connected to the multiplexer (10); The amplitude and phase detection module (1) is connected to the multiplexer (10); The multiplexer (10) is connected to the input end of the analog-to-digital conversion module (3).

6. The battery management circuit according to claim 2, characterized in that: The waveform generator (2) comprises: a hysteresis voltage comparator (21), a first switch unit (22), a sign circuit (23), an inverting integrator (24) and a voltage-current converter (25), wherein: The first end of the hysteresis voltage comparator (21) is connected to the second end of the inverting integrator (24), and the second end of the hysteresis voltage comparator (21) is connected to the control end of the first switch unit (22); The first switch unit (22) is connected between a first end of the sign circuit (23) and a ground end; The second end of the sign circuit (23) is connected to the first end of the inverting integrator (24); The second end of the inverting integrator (24) is connected to the first end of the voltage-current converter (25); The second end of the voltage-current converter (25) is connected to the positive electrode of the battery and the first input end of the amplitude and phase detection module (1) respectively.

7. The battery management circuit according to claim 6, characterized in that: The waveform generator (2) further comprises a voltage reduction unit (26), wherein: The second end of the inverting integrator (24) is connected to the first end of the voltage-current converter (25) through the voltage-step-down unit (26).

8. The battery management circuit according to claim 6, characterized in that: The waveform generator (2) further comprises a current limiting unit (27), wherein: The second end of the hysteresis voltage comparator (21) is connected to the control end of the first switch unit (22) through the current limiting unit (27).

9. The battery management circuit according to claim 6, characterized in that: The hysteresis voltage comparator (21) comprises: a first resistor (R1), a second resistor (R2), a third resistor (R3), a fourth resistor (R4), a first operational amplifier (U1) and a third diode (D3), wherein: The inverting input terminal of the first operational amplifier (U1) is connected to the second terminal of the inverting integrator (24), the non-inverting input terminal of the first operational amplifier (U1) is grounded via the second resistor (R2), and the output terminal of the first operational amplifier (U1) is connected to the first terminal of the first resistor (R1); The third resistor (R3) is connected between the non-inverting input terminal of the first operational amplifier (U1) and the second end of the first resistor (R1); The fourth resistor (R4) is connected between the second end of the first resistor (R1) and the control end of the first switch unit (22); An anode of the third diode (D3) is connected to the control end of the first switch unit (22), and a cathode of the third diode (D3) is grounded.

10. The battery management circuit according to claim 9, characterized in that: The hysteresis voltage comparator (21) further comprises: a first diode (D1) and a second diode (D2), wherein: The second end of the first resistor (R1) is connected to the cathode of the first diode (D1); The anode (D1) of the first diode is connected to the anode of the second diode (D2); The cathode of the second diode (D2) is grounded; Wherein, the first diode (D1) and the second diode (D2) are voltage-stabilizing diodes.

11. The battery management circuit according to claim 6, characterized in that: The symbol circuit (23) comprises: a fundamental wave generator (W), a sixth resistor (R6), a seventh resistor (R7), a second operational amplifier (U2), an eighth resistor (R8) and a ninth resistor (R9), wherein: The fundamental wave generator (W) is connected to the ground terminal and the first end of the sixth resistor (R6); The second end of the sixth resistor (R6) is connected to the first switch unit (22); The seventh resistor (R7) is connected between the second end of the sixth resistor (R6) and the non-inverting input end of the second operational amplifier (U2); The eighth resistor (R8) is connected between the ground terminal and the inverting input terminal of the second operational amplifier (U2); The ninth resistor (R9) is connected between the inverting input terminal of the second operational amplifier (U2) and the output terminal of the second operational amplifier (U2); The output end of the second operational amplifier (U2) is connected to the first end of the inverting integrator (24).

12. The battery management circuit according to claim 11, characterized in that: The fundamental wave generator (W) is a square wave generator.

13. The battery management circuit according to claim 6, characterized in that: The inverting integrator (24) comprises: a tenth resistor (R10), a first capacitor (C1) and a third operational amplifier (U3), wherein: The tenth resistor (R10) is connected between the second end of the sign circuit (23) and the inverting input end of the third operational amplifier (U3); The non-inverting input terminal of the third operational amplifier (U3) is grounded, the output terminal of the third operational amplifier (U3) is connected to the second terminal of the sign circuit (23) via the first capacitor (C1), and the output terminal of the third operational amplifier (U3) is connected to the voltage-current converter (25).

14. The battery management circuit according to claim 6, characterized in that: The voltage-current converter (25) comprises: an eleventh resistor (R11), a twelfth resistor (R12), a thirteenth resistor (R13), a fourteenth resistor (R14), a fifteenth resistor (R15) and a fourth operational amplifier (U4), wherein: The eleventh resistor (R11) is connected between the non-inverting input terminal of the fourth operational amplifier (U4) and the ground terminal; The twelfth resistor (R12) is connected between the output terminal of the fourth operational amplifier (U4) and the inverting input terminal of the fourth operational amplifier (U4); The thirteenth resistor (R13) and the fourteenth resistor (R14) are connected in series and then connected between the output terminal of the fourth operational amplifier (U4) and the ground terminal; The fifteenth resistor (R15) is connected to the second end of the inverting integrator (24) and the inverting input end of the fourth operational amplifier (U4); The non-inverting input terminal of the fourth operational amplifier (U4) is connected to the first middle point (M), wherein the first middle point (M) is the connection point of the thirteenth resistor (R13) and the fourteenth resistor (R14); The first intermediate point (M) is connected to the positive electrode of the battery.

15. The battery management circuit according to claim 7, characterized in that: The voltage reduction unit (26) comprises: a first inductor (L1), a fourth diode (D4), a second capacitor (C2) and a second switch unit (Q2), wherein: The second switch unit (Q2) is connected between the second end of the inverting integrator (24) and the first end of the first inductor (L1), and the control end of the second switch unit (Q2) is used to receive a step-down control signal; The cathode of the fourth diode (D4) is connected to the first end of the first inductor (L1), and the anode of the fourth diode (D4) is grounded; The second capacitor (C2) is connected between the second end of the first inductor (L1) and the ground end; The second end of the first inductor (L1) is connected to the first end of the voltage-current converter (25).

16. The battery management circuit according to claim 8, characterized in that: The current limiting unit (27) is a fifth resistor (R5).

17. The battery management circuit according to claim 16, characterized in that: The voltage-current converter (25) comprises: an eleventh resistor (R11), a twelfth resistor (R12), a thirteenth resistor (R13), a fourteenth resistor (R14), a fifteenth resistor (R15), a fourth operational amplifier (U4) and a fifth operational amplifier (U5), wherein: The eleventh resistor (R11) is connected to the second end of the inverting integrator (24) and the non-inverting input end of the fourth operational amplifier (U4); The twelfth resistor (R12) is connected between the output terminal of the fourth operational amplifier (U4) and the inverting input terminal of the fourth operational amplifier (U4); The thirteenth resistor (R13) is connected between the output terminal of the fourth operational amplifier (U4) and the non-inverting input terminal of the fifth operational amplifier (U5); The fourteenth resistor (R14) is connected between the output terminal of the fifth operational amplifier (U5) and the non-inverting input terminal of the fourth operational amplifier; The fifteenth resistor (R15) is connected between the inverting input terminal of the fourth operational amplifier (U4) and the ground terminal; The inverting input terminal of the fifth operational amplifier (U5) is connected to the output terminal of the fifth operational amplifier (U5), and the non-inverting input terminal of the fifth operational amplifier (U5) is connected to the positive electrode of the battery.

18. The battery management circuit according to claim 17, characterized in that: The voltage-current converter (25) further includes: an eleventh resistor (R11), a twelfth resistor (R12), a thirteenth resistor (R13), a fourteenth resistor (R14), a fifteenth resistor (R15), a sixteenth resistor (R16), a seventeenth resistor (R17), an eighteenth resistor (R18), a fourth operational amplifier (U4) and a fifth operational amplifier (U5), wherein: The eleventh resistor (R11) is connected to the second end of the inverting integrator (24) and the non-inverting input end of the fourth operational amplifier (U4); The twelfth resistor (R12) is connected between the output terminal of the fourth operational amplifier (U4) and the inverting input terminal of the fourth operational amplifier (U4); The thirteenth resistor (R13) is connected between the output terminal of the fourth operational amplifier (U4) and the non-inverting input terminal of the fifth operational amplifier (U5); The fifteenth resistor (R15) is connected between the inverting input terminal of the fourth operational amplifier (U4) and the ground terminal; The fourteenth resistor (R14), the eighteenth resistor (R18), and the sixteenth resistor (R16) are sequentially connected in series to the non-inverting input terminal of the fourth operational amplifier (U4) and the non-inverting input terminal of the fifth operational amplifier (U5); The seventeenth resistor (R17) is connected between the output terminal of the fourth operational amplifier (U4) and the second intermediate point (N), wherein the second intermediate point (N) is the connection point between the fourteenth resistor (R14) and the eighteenth resistor (R18); The second intermediate point (N) is connected to the positive electrode of the battery.

19. The battery management circuit according to claim 1, characterized in that: The amplitude and phase detection module 1 comprises: an amplitude detection unit (11) and a phase detection unit (12), wherein: The first input end of the amplitude detection unit (11) is connected to the output end of the waveform generator (2), and the second input end of the amplitude detection unit (11) is connected to the positive electrode of the battery; The first input end of the phase detection unit (12) is connected to the output end of the waveform generator (2), and the second input end of the phase detection unit (12) is connected to the positive electrode of the battery.

20. The battery management circuit according to claim 19, characterized in that: The amplitude detection unit (11) comprises: a first detection circuit (111), a second detection circuit (112) and a nineteenth resistor (R19), wherein: The first end of the first detection circuit (111) is connected to the output end of the waveform generator (2); The first end of the second detection circuit (112) is connected to the positive electrode of the battery; The nineteenth resistor (R19) is connected between the second end of the first detection circuit (111) and the second end of the second detection circuit (112).

21. The battery management circuit according to claim 20, characterized in that: The first detection circuit (111) comprises: a fifth diode (D5), wherein: The anode of the fifth diode (D5) is connected to the output end of the waveform generator (2), and the cathode of the fifth diode (D5) is connected to the nineteenth resistor (R19).

22. The battery management circuit according to claim 21, characterized in that: The first detection circuit (111) further comprises a first filtering circuit (1111), wherein: The first filter circuit (1111) is connected between the cathode of the fifth diode (D5) and the ground terminal.

23. The battery management circuit according to claim 22, characterized in that: The first filtering circuit (1111) comprises: a twenty-first resistor (21) R and a third capacitor (C3), wherein: The twenty-first resistor (R21) and the third capacitor (C3) are respectively connected in parallel between the cathode of the fifth diode (D5) and the ground terminal.

24. The battery management circuit according to claim 20, characterized in that: The second detection circuit (112) comprises: a sixth diode (D6), wherein: The cathode of the sixth diode (D6) is connected to the positive electrode of the battery, and the anode of the sixth diode (D6) is connected to the nineteenth resistor (R19).

25. The battery management circuit according to claim 24, characterized in that: The second detection circuit (112) further comprises: a second filtering circuit (1121), wherein: The second filter circuit (1121) is connected between the anode of the sixth diode (D6) and the ground terminal.

26. The battery management circuit according to claim 25, characterized in that: The second filtering circuit (1121) comprises: a twenty-second resistor (R22) and a fourth capacitor (C4), wherein: The twenty-second resistor (R22) and the fourth capacitor (C4) are respectively connected in parallel between the anode of the sixth diode (D6) and the ground terminal.

27. The battery management circuit according to claim 19, characterized in that: The phase detection unit (12) comprises: a third detection circuit (122), a fourth detection circuit (123), a twentieth resistor (R20), an addition circuit (121) and a subtraction circuit (124), wherein: A first end of the adding circuit (121) is connected to the output end of the waveform generator (2), and a second end of the adding circuit (121) is connected to the positive electrode of the battery; The first end of the third detection circuit (122) is connected to the third end of the adding circuit (121); A first end of the subtraction circuit (124) is connected to the output end of the waveform generator (2), and a second end of the subtraction circuit (124) is connected to the positive electrode of the battery; The first end of the fourth detection circuit (123) is connected to the third end of the subtraction circuit (124); The twentieth resistor (R20) is connected between the second end of the third detection circuit (122) and the second end of the fourth detection circuit (123).

28. The battery management circuit according to claim 27, characterized in that: The third detection circuit (122) comprises: a seventh diode (D7), wherein: The cathode of the seventh diode (D7) is connected to the third end of the adding circuit (121), and the anode of the seventh diode (D7) is connected to the twentieth resistor (R20).

29. The battery management circuit according to claim 28, characterized in that: The third detection circuit (122) further comprises: a third filtering circuit (1221), wherein: The third filter circuit (1221) is connected between the anode of the seventh diode (D7) and the ground terminal.

30. The battery management circuit according to claim 27, characterized in that: The fourth detection circuit (123) comprises: an eighth diode (D8), wherein: The anode of the eighth diode (D8) is connected to the third end of the subtraction circuit (124), and the cathode of the eighth diode (D8) is connected to the twentieth resistor (R20).

31. The battery management circuit according to claim 30, characterized in that: The fourth detection circuit (123) further comprises: a fourth filtering circuit (1231), wherein: The fourth filtering circuit (1231) is connected between the cathode of the eighth diode (R20) and the ground terminal.

32. The battery management circuit according to claim 27, characterized in that: The adding circuit (121) comprises: a twenty-third resistor (R23), a twenty-fourth resistor (R24), a twenty-fifth resistor (R25), a twenty-sixth resistor (R26), a twenty-seventh resistor (R27) and a sixth operational amplifier (U6), wherein: The twenty-third resistor (R23) is connected between the ground terminal and the inverting input terminal of the sixth operational amplifier (U6); The twenty-fourth resistor (R24) is connected between the inverting input terminal of the sixth operational amplifier (U6) and the output terminal of the sixth operational amplifier; The twenty-fifth resistor (R25) is connected between the output end of the waveform generator (2) and the non-inverting input end of the sixth operational amplifier (U6); The twenty-sixth resistor (R26) is connected between the positive electrode of the battery and the non-inverting input terminal of the sixth operational amplifier (U6); The twenty-seventh resistor (R27) is connected between the non-inverting input terminal of the sixth operational amplifier (U6) and the ground terminal; The output end of the sixth operational amplifier (U6) is connected to the first end of the third detection circuit (122).

33. The battery management circuit according to claim 27, characterized in that: The subtraction circuit (124) comprises: a twenty-eighth resistor (R28), a twenty-ninth resistor (R29), a thirtieth resistor (R30), a thirty-first resistor (R31) and a seventh operational amplifier (U7), wherein: The twenty-eight resistors (R28) are connected between the inverting input terminal of the seventh operational amplifier (U7) and the output terminal of the seventh operational amplifier (U7); The output end of the seventh operational amplifier (U7) is connected to the first end of the fourth detection circuit (123); The twenty-ninth resistor (R29) is connected between the inverting input terminal of the seventh operational amplifier (U7) and the output terminal of the waveform generator (2); The thirtieth resistor (R30) is connected between the non-inverting input of the seventh operational amplifier (U7) and the positive electrode of the battery; The thirty-first resistor (R31) is connected between the non-inverting input terminal of the seventh operational amplifier (U7) and the ground terminal.

34. A battery management chip, characterized in that: The battery management chip comprises a battery management circuit as described in any one of claims 1-33.

35. A vehicle, characterized in that: The vehicle includes the battery management chip as claimed in claim 34.

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