Signal processing method and device for lithium battery and electronic equipment

Abstract

The invention discloses a signal processing method and device for a lithium battery and electronic equipment, and relates to the technical field of lithium battery data processing, and the method comprises the steps: obtaining an output signal of a target ultrasonic sensor disposed on the surface of the lithium battery; the output signal is transmitted to a target filter, parameters of the target filter are adjusted based on the output signal, and the value range corresponding to the parameters of the target filter is determined based on historical output signals of an ultrasonic sensor arranged on the surface of the lithium battery; and filtering the output signal by using the adjusted target filter to obtain a filtered signal, and transmitting the filtered signal to a lithium battery management system to monitor the lithium battery. According to the method, the output signals of the ultrasonic sensor can be effectively screened, and the filtering effect, the universality and the usability can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of lithium battery data processing, and in particular to a signal processing method, device and electronic equipment for lithium batteries. Background Art

[0002] With the rapid development of new energy technologies, lithium-ion batteries have become the core technology of electrochemical energy storage due to their high energy density, no memory effect, and low self-discharge rate. However, lithium-ion batteries contain high-energy active substances, which are prone to thermal runaway under external abuse conditions, causing safety hazards. Monitoring their safety status has become a problem that needs to be solved urgently.

[0003] Ultrasonic waves are non-destructive, highly sensitive, and have strong penetrating power. Placing ultrasonic sensors on the surface of lithium batteries can effectively obtain the charge state and health status of the battery. However, the output signal of ultrasonic sensors is relatively complex, and a filter is needed to filter out interference signals.

[0004] Traditional bandpass filters with fixed passband cutoff frequencies cannot adjust the passband cutoff frequency according to the characteristic frequency of the output signal when the ultrasonic sensor can only be installed at a certain position of the lithium battery. The noise reduction effect cannot meet the requirements and there is a possibility of missing important information. If a bandpass filter is designed separately for each optional installation position of the ultrasonic sensor and each individual lithium battery, the parameter design process will be complicated and costly.

[0005] Currently, no effective solution has been proposed to the above-mentioned problem of being unable to accurately and effectively filter the output signal of the lithium battery ultrasonic sensor. Summary of the invention

[0006] The purpose of the embodiments of the present application is to provide a signal processing method, device and electronic device for a lithium battery, so as to solve the problem that the output signal of a lithium battery ultrasonic sensor cannot be accurately and effectively filtered.

[0007] In order to solve the above technical problems, the first aspect of this specification provides a signal processing method for a lithium battery, comprising:

[0008] Acquire an output signal of a target ultrasonic sensor disposed on the surface of a lithium battery;

[0009] The output signal is transmitted to a target filter, and parameters of the target filter are adjusted based on the output signal and the target ultrasonic sensor at a target position on the surface of the lithium battery; wherein a value range corresponding to the parameter of the target filter is determined based on a historical output signal of the ultrasonic sensor disposed on the surface of the lithium battery;

[0010] The output signal is filtered using the adjusted target filter to obtain a filtered signal, and the filtered signal is transmitted to a lithium battery management system to monitor the lithium battery.

[0011] In some embodiments of this specification, the value range corresponding to the parameter of the target filter is determined by:

[0012] Acquire multiple historical output signals of an ultrasonic sensor disposed on the surface of the lithium battery, wherein the multiple historical output signals are signals collected and output by the ultrasonic sensor at multiple locations on the surface of the lithium battery;

[0013] Processing the multiple historical output signals to determine the characteristic frequency of each historical output signal;

[0014] Based on the determined multiple characteristic frequencies and the parameters of the lithium battery, determining a first proportionality coefficient between the passband width of the target filter and the characteristic frequency;

[0015] Determining a passband adjustment range of the target filter based on the determined multiple characteristic frequencies, the parameters of the lithium battery, and the first proportional coefficient;

[0016] Based on the passband adjustment range, the values ​​of the parameters of the capacitor, resistor and potentiometer in the target filter are determined.

[0017] In some embodiments of the present specification, based on the determined multiple characteristic frequencies and the parameters of the lithium battery, determining a first proportionality coefficient between the passband width of the target filter and the characteristic frequency includes:

[0018] Collecting the first output signal of the ultrasonic sensor at different characteristic frequencies and under different lithium battery working conditions;

[0019] Collect the second output signal of the ultrasonic sensor under different lithium battery parameters, different installation positions and different lithium battery working conditions;

[0020] determining a maximum value among the plurality of characteristic frequencies;

[0021] The first proportionality coefficient is determined based on the first output signal, the second output signal, and the maximum value.

[0022] In some embodiments of the present specification, determining the first proportionality coefficient based on the first output signal, the second output signal and the maximum value includes:

[0023] Based on the first output signal, determining a first frequency variation range of the ultrasonic sensor output signal that varies with the working state of the lithium battery at different characteristic frequencies;

[0024] Obtaining a first relationship between a characteristic frequency and a first parameter in a preset function satisfied by the first proportional coefficient based on fitting of the first frequency variation range, and determining a value of the first parameter corresponding to the maximum value based on the maximum value and the first relationship;

[0025] Based on the second output signal, determining a second frequency variation range of the ultrasonic sensor output signal that changes with the working state of the lithium battery under different lithium battery parameters and different installation positions;

[0026] Based on the second frequency variation range, a second relationship between the lithium battery parameter, the installation position and the second parameter of the preset function is determined by using a cluster analysis method, and a value of the second parameter is determined based on the second relationship;

[0027] The first proportional coefficient is determined based on the value of the first parameter, the value of the second parameter and the preset function.

[0028] In some embodiments of this specification, the first proportionality coefficient is determined by the following formula:

[0029] τ = αe -β ;

[0030] Among them, τ represents the first proportional coefficient, α represents the first parameter in the preset function satisfied by the first proportional coefficient, β represents the second parameter in the preset function satisfied by the first proportional coefficient, and the first parameter and the second parameter are determined based on the first output signal, the second output signal and the maximum value.

[0031] In some embodiments of this specification, determining the passband adjustment range of the target filter based on the determined multiple characteristic frequencies, the parameters of the lithium battery, and the first proportional coefficient includes:

[0032] Determining a maximum passband width of the target filter based on the first proportionality coefficient and a maximum value of the plurality of characteristic frequencies;

[0033] Measuring a third output signal of an ultrasonic sensor disposed on the surface of lithium batteries of different lithium battery models;

[0034] Determine the value range of the characteristic frequency of the third output signal corresponding to each lithium battery model;

[0035] Based on the value range and the preset characteristic frequency distribution condition, determining a second proportionality coefficient between the passband adjustment range and the maximum passband width;

[0036] The passband adjustment range is determined based on the second proportionality coefficient, the maximum passband width, and the maximum and minimum values ​​of a plurality of characteristic frequencies.

[0037] In some embodiments of the present specification, the passband adjustment range is determined by the following formula:

[0038] ;

[0039] Among them, BW Max represents the maximum passband width of the target filter, f CMax Represents the maximum value among multiple characteristic frequencies, f CMin Represents the minimum value among multiple characteristic frequencies, f Max Indicates the maximum value of the passband adjustment range, f Min represents the minimum value of the passband adjustment range, and θ represents the second proportional coefficient between the passband adjustment range and the maximum passband width.

[0040] In some embodiments of this specification, after determining the passband adjustment range of the target filter based on the determined multiple characteristic frequencies, the parameters of the lithium battery, and the first proportional coefficient, the method further includes:

[0041] determining a plurality of passband ranges based on the passband adjustment range;

[0042] Adjusting the quality factor corresponding to each passband range, and determining whether the quality factor corresponding to each passband range meets a preset condition based on the adjustment result;

[0043] When it is determined that the quality factor corresponding to any passband range does not meet the preset conditions, the parameters of the target filter are adjusted; the parameters of the target filter include at least one of the following: passband width, passband adjustment range, capacitance value, resistance value and parameter value of potentiometer.

[0044] In some embodiments of the present specification, the target filter includes at least one second-order active low-pass filter module and at least one second-order active high-pass filter module connected in series.

[0045] In some embodiments of the present specification, the second-order active low-pass filter module and / or the second-order active high-pass filter module includes a potentiometer, and the output characteristic of the potentiometer is one of the following: inverse proportional, exponential, and preset function.

[0046] In some embodiments of the present specification, adjusting the parameters of the target filter based on the output signal and the target position of the target ultrasonic sensor on the surface of the lithium battery includes:

[0047] determining at least one characteristic frequency corresponding to the output signal from among the plurality of characteristic frequencies based on the target position;

[0048] The variation range of the at least one characteristic frequency is determined, and the parameters of the potentiometer in the target filter are adjusted based on the variation range of the at least one characteristic frequency, so that the passband of the adjusted target filter covers the variation range of the at least one characteristic frequency.

[0049] A second aspect of the present specification provides a signal processing device for a lithium battery, comprising:

[0050] A signal acquisition module, used to acquire an output signal of a target ultrasonic sensor disposed on the surface of the lithium battery;

[0051] A parameter adjustment module, used for transmitting the output signal to a target filter, and adjusting the parameters of the target filter based on the output signal and the target position of the target ultrasonic sensor on the surface of the lithium battery; wherein the value range corresponding to the parameter of the target filter is determined based on the historical output signal of the ultrasonic sensor provided on the surface of the lithium battery;

[0052] The signal processing module is used to filter the output signal using the adjusted target filter to obtain a filtered signal, and transmit the filtered signal to the lithium battery management system to monitor the lithium battery.

[0053] The third aspect of this specification provides an electronic device, comprising: a memory and a processor, the processor and the memory are communicatively connected to each other, the memory stores computer instructions, and the processor executes the computer instructions to perform the steps of the method described in the first aspect.

[0054] A fourth aspect of the present specification provides a computer storage medium, wherein the computer storage medium stores computer program instructions, and when the computer program instructions are executed, the steps of the method described in the first aspect are implemented.

[0055] A fifth aspect of the present specification provides a computer program product, comprising a computer program, which, when executed by a processor, implements the steps of the method described in the first aspect.

[0056] The signal processing method, device and electronic device for lithium batteries in the embodiments of this specification determine the value range corresponding to the parameters of the target filter through the historical output signal of the ultrasonic sensor disposed on the surface of the lithium battery, obtain the target filter with adjustable parameters, and when using the filter to filter the signal, obtain the output signal of the target ultrasonic sensor disposed on the surface of the lithium battery; transmit the output signal to the target filter, adjust the parameters of the target filter based on the output signal; use the adjusted target filter to filter the output signal to obtain the filtered signal, and transmit the filtered signal to the lithium battery management system to monitor the lithium battery. Through the above method, the target filter can adapt to the range fluctuations of the ultrasonic filter on the surface of the lithium battery due to the changes in the working state of the lithium battery and the differences in the shells of different lithium batteries, and the effective screening of the output signal of the ultrasonic sensor can be achieved only by adjusting the parameters of the filter, which can improve the filtering effect, versatility and ease of use. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some implementation methods recorded in this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0058] Figure 1 Shown is a schematic diagram of a signal processing method for a lithium battery provided in an embodiment of this specification;

[0059] Figure 2 FIG. 1 is a schematic diagram of a method for determining a value range of a filter parameter provided in an embodiment of this specification;

[0060] Figure 3 Shown is a schematic diagram of a second-order active high-pass filter module and a second-order active low-pass filter module provided in an embodiment of this specification;

[0061] Figure 4 Shown is a schematic diagram of amplitude-frequency characteristic curves of different filters provided in the embodiments of this specification;

[0062] Figure 5 Shown is a schematic diagram of the amplitude-frequency characteristic curves of different passbands of the filter provided in the embodiment of this specification;

[0063] Figure 6 Shown is a schematic diagram of a signal processing device for a lithium battery provided in an embodiment of this specification;

[0064] Figure 7Shown is a schematic diagram of an electronic device provided in an embodiment of this specification. DETAILED DESCRIPTION

[0065] In order to enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this application.

[0066] It should be noted that the user-related information and data involved in the embodiments of this specification are all information and data authorized by the user or fully authorized by relevant parties, and the collection, storage, use, processing, transmission, provision, disclosure and application of the relevant data comply with relevant laws, regulations and standards, take necessary confidentiality measures, do not violate public order and good morals, and provide corresponding operation entrances for users or relevant parties to choose to authorize or refuse.

[0067] It should also be noted that in the embodiments of this specification, certain software, components, models and other existing solutions in the industry may be mentioned. They should be regarded as exemplary. Their purpose is only to illustrate the feasibility of implementing the technical solution of this application, but it does not mean that the applicant has or will necessarily use the solution.

[0068] Ultrasonic sensors are placed on the surface of lithium batteries to effectively obtain the charge state and health status of the battery. When ultrasonic sensors are installed in different positions, the characteristic frequency of the sensor output signal will vary within a large range; for the same ultrasonic sensor installation position, when the working state of the lithium battery changes, the characteristic frequency of the sensor output signal will fluctuate within a small range; for the same model of lithium battery, when the ultrasonic sensor is used on different individuals, the characteristic frequency of the sensor output signal will also vary within a small range.

[0069] At present, two methods are generally used to achieve this: one is to apply it to the filter, by reciprocally changing the port network composed of any combination of parallel elements and series elements in the resonant unit, forming a capacitive and inductive reciprocal unit, and adjusting the coupling coefficient according to the requirements of the selected frequency band. However, this method cannot meet the needs of the application scenarios of lithium battery ultrasonic sensors. Another method is to add devices on the surface of the sensor to achieve selective reception and filtering of ultrasonic waves of a specific frequency, and then perform subsequent filtering. This method is not suitable for scenarios where the frequency of the output signal of the ultrasonic sensor changes, and the filtering effect is poor. It can be seen that the existing scheme cannot accurately and effectively filter the output signal of the lithium battery ultrasonic sensor.

[0070] In order to solve the above problems, the embodiments of this specification have made specific optimizations for lithium battery ultrasonic signals when designing filter parameters, and designed reasonable parameters based on the characteristics of lithium batteries, so that the filter's passband width and other parameter indicators are more in line with the actual application scenarios of ultrasonic monitoring of lithium batteries, and can meet the needs of processing lithium battery characteristic signals. In addition, a bandpass filter with a continuously adjustable passband position is designed, so that when the frequency of the lithium battery characteristic signal changes, the characteristic frequency can be covered by adjusting the filter passband position to achieve the expected filtering effect; and there is no need to screen signals of specific frequencies through ultrasonic sensors, reducing system costs and design complexity.

[0071] Specifically, the embodiments of this specification provide a signal processing method, device and electronic device for lithium batteries, which determine the value range corresponding to the parameters of the target filter through the historical output signal of the ultrasonic sensor disposed on the surface of the lithium battery, and obtain the target filter with adjustable parameters. When using the filter to filter the signal, the output signal of the target ultrasonic sensor disposed on the surface of the lithium battery is obtained; the output signal is transmitted to the target filter, and the parameters of the target filter are adjusted based on the output signal; the output signal is filtered using the adjusted target filter to obtain a filtered signal, and the filtered signal is transmitted to the lithium battery management system to monitor the lithium battery.

[0072] Through the above method, the target filter can adapt to the range fluctuations of the ultrasonic filter on the surface of the lithium battery due to changes in the working state of the lithium battery and differences in different lithium battery shells, and the output signal of the ultrasonic sensor can be effectively screened only by adjusting the parameters of the filter, which can improve the filtering effect, versatility and ease of use.

[0073] It can be understood that the above method provided in the present application can be applied to electronic devices, and the electronic devices can refer to electronic devices with data calculation, processing and storage capabilities. The electronic device can be a terminal such as a PC (Personal Computer), a tablet computer, a smart phone, a wearable device, an intelligent robot, etc.; it can also be a server. Among them, the server can be an independent physical server, or a server cluster or distributed system composed of multiple physical servers, or a cloud server that provides cloud computing services.

[0074] Figure 1Shown is a schematic diagram of a signal processing method for a lithium battery provided in an embodiment of this specification. Although this specification provides method operation steps or device structures as shown in the following embodiments or drawings, the method or device may include more or fewer operation steps or module units after partial merger based on routine or no creative labor. In steps or structures where there is no necessary causal relationship logically, the execution order of these steps or the module structure of the device is not limited to the execution order or module structure shown in the embodiments or drawings of this specification. When the method or module structure described is applied in actual devices, servers or terminal products, it can be executed sequentially or in parallel according to the method or module structure shown in the embodiments or drawings (for example, in a parallel processor or multi-threaded processing environment, or even in a distributed processing or server cluster implementation environment). As Figure 1 As shown, the method may include:

[0075] S101: Acquire an output signal of a target ultrasonic sensor disposed on the surface of a lithium battery.

[0076] It can be understood that the output signal can be a real-time output signal of the target ultrasonic sensor, or a signal to be processed by the target ultrasonic sensor. The target ultrasonic sensor can be set at any position on the surface of the lithium battery, or the position of the target ultrasonic sensor can be set based on actual application requirements. The target ultrasonic sensor can output an ultrasonic signal to the inside of the lithium battery and receive the ultrasonic signal returned, and then monitor the health status of the lithium battery through the ultrasonic signal sent and received.

[0077] S102: Transmit the output signal to a target filter, and adjust parameters of the target filter based on the output signal and the target ultrasonic sensor at a target position on the surface of the lithium battery; wherein the value range corresponding to the parameters of the target filter is determined based on a historical output signal of the ultrasonic sensor disposed on the surface of the lithium battery.

[0078] It can be understood that the target filter can be arranged between the target ultrasonic sensor and the lithium battery management system for processing its output signal. Since the output signal of the target ultrasonic sensor is easily interfered by environmental factors and other factors during the signal transmission process, it is necessary to use a filter to filter the output signal of the target ultrasonic sensor before analyzing and determining the health status of the lithium battery based on the output signal. In addition, since the output signal of the target ultrasonic sensor is affected by the changes in the working state of the lithium battery or the target position, etc., there will be certain changes. Therefore, after receiving the output signal, the parameters of the target filter can be adjusted based on the output signal and the target position of the target ultrasonic sensor to adapt to the changes in the current working environment and achieve better filter effects.

[0079] In some embodiments of the present specification, adjusting the parameters of the target filter based on the output signal and the target position of the target ultrasonic sensor on the surface of the lithium battery may include: determining at least one characteristic frequency corresponding to the output signal among the multiple characteristic frequencies based on the target position; determining a variation range of the at least one characteristic frequency, and adjusting the parameters of the potentiometer in the target filter based on the variation range of the at least one characteristic frequency so that the passband of the adjusted target filter covers the variation range of the at least one characteristic frequency.

[0080] Specifically, the lower cutoff frequency in the passband of the adjusted target filter needs to be greater than the minimum value in the variation range of at least one characteristic frequency, and the upper cutoff frequency needs to be less than the maximum value in the variation range of at least one characteristic frequency.

[0081] S103: Filter the output signal using the adjusted target filter to obtain a filtered signal, and transmit the filtered signal to a lithium battery management system to monitor the lithium battery.

[0082] In some embodiments of the present specification, the target filter may include at least one second-order active low-pass filter module and at least one second-order active high-pass filter module connected in series. Of course, it is understandable that the filter module in the target filter may be a module with a higher order, and the present specification does not limit this.

[0083] In some embodiments of the present specification, the second-order active low-pass filter module and / or the second-order active high-pass filter module may include a potentiometer, and the output characteristic of the potentiometer is one of the following: inverse proportional, exponential, and preset function. Specifically, the filter module may include at least one potentiometer, a resistor, an operational amplifier chip, a capacitor, and the like.

[0084] It can be understood that the output characteristic of the potentiometer can be understood as the change relationship between the position of the potentiometer adjustment knob and the resistance value derived therefrom, and the change relationship satisfies one of an inverse proportional function, an exponential function, and a preset function, so that the cutoff frequency of the filter module using the potentiometer is approximately linear or linear. Furthermore, the cutoff frequency of the second-order active filter module can be adjusted approximately linearly or linearly based on the potentiometer adjustment knob.

[0085] The value range corresponding to the parameters of the target filter in the embodiment of this specification can be determined based on the historical output signal of the ultrasonic sensor arranged on the surface of the lithium battery. The parameter design process will be further introduced below with reference to the accompanying drawings.

[0086] Reference Figure 2As shown, in some embodiments of this specification, the process of determining the value range corresponding to the parameter of the target filter may include the following steps:

[0087] S201: Acquire a plurality of historical output signals of an ultrasonic sensor disposed on a surface of a lithium battery, wherein the plurality of historical output signals are signals collected and output by the ultrasonic sensor at a plurality of locations on the surface of the lithium battery.

[0088] Specifically, the installation position of the ultrasonic sensor on the surface of the lithium battery can be changed, and the output signals of the ultrasonic sensors at various installation positions under different working conditions of the lithium battery can be collected as multiple historical output signals.

[0089] S202: Process the multiple historical output signals to determine the characteristic frequency of each historical output signal.

[0090] It can be understood that the multiple historical output signals are time domain signals. The multiple historical output signals can be subjected to Fourier transform to obtain multiple frequency domain signals, and the frequency component with the largest intensity in each frequency domain signal can be determined as the characteristic frequency of the frequency domain signal. The multiple characteristic frequencies obtained can be combined into a characteristic frequency set.

[0091] S203: Determine a first proportionality coefficient between the passband width of the target filter and the characteristic frequency based on the determined multiple characteristic frequencies and the parameters of the lithium battery.

[0092] It can be understood that there is a certain proportional relationship between the passband width and the characteristic frequency, that is, the first proportional coefficient. The first proportional coefficient can be related to the characteristic frequency, the material of the lithium battery casing, and the installation position of the ultrasonic sensor. Therefore, the first proportional coefficient can be determined based on multiple characteristic frequencies and lithium battery parameters.

[0093] In some embodiments of the present specification, determining a first proportional coefficient between the passband width of the target filter and the characteristic frequency based on multiple determined characteristic frequencies and parameters of the lithium battery may include: collecting a first output signal of an ultrasonic sensor under different characteristic frequencies and different lithium battery operating conditions; collecting a second output signal of an ultrasonic sensor under different lithium battery parameters, different installation positions and different lithium battery operating conditions; determining a maximum value among the multiple characteristic frequencies; and determining the first proportional coefficient based on the first output signal, the second output signal and the maximum value.

[0094] It can be understood that when determining the first proportionality coefficient, the frequency data of the signal output by the ultrasonic sensor under different characteristic frequencies and lithium battery parameters can be collected, and the first proportionality coefficient can be determined by a cluster analysis method.

[0095] Furthermore, determining the first proportionality coefficient based on the first output signal, the second output signal and the maximum value may include: determining a first frequency variation range of the ultrasonic sensor output signal that changes with the working state of the lithium battery at different characteristic frequencies based on the first output signal; fitting a first relationship between the characteristic frequency and a first parameter in a preset function satisfied by the first proportionality coefficient based on the first frequency variation range, and determining the value of the first parameter corresponding to the maximum value based on the maximum value and the first relationship; determining a second frequency variation range of the ultrasonic sensor output signal that changes with the working state of the lithium battery at different lithium battery parameters and different installation positions based on the second output signal; determining a second relationship between the lithium battery parameters, the installation position and the second parameter of the preset function based on the second frequency variation range using a cluster analysis method, and determining the value of the second parameter based on the second relationship; determining the first proportionality coefficient based on the value of the first parameter, the value of the second parameter and the preset function.

[0096] Furthermore, the first proportionality coefficient can be determined by the following formula:

[0097] τ = αe -β Formula (1)

[0098] Among them, τ can represent a first proportional coefficient, α can represent a first parameter in a preset function satisfied by the first proportional coefficient, β can represent a second parameter in a preset function satisfied by the first proportional coefficient, and the first parameter and the second parameter are determined based on the first output signal, the second output signal and the maximum value.

[0099] Specifically, the method for determining the first parameter α is to measure the frequency variation range of the ultrasonic sensor output signal under different characteristic frequencies as the working state of the lithium battery changes, and fit the relationship between the characteristic frequency and α, so that the passband width BW obtained by the first proportional coefficient τ can always cover the variation range of the output signal. The method for determining the second parameter β is to measure the frequency variation range of the ultrasonic sensor output signal under different lithium battery shell materials and ultrasonic sensor installation positions as the working state of the lithium battery changes, and use cluster analysis on the above conditions and relationships, so that the passband width BW obtained by the first proportional coefficient τ can always cover the variation range of the output signal.

[0100] Exemplarily, the first parameter α is the maximum value f among the multiple characteristic frequencies CMax The relevant parameters may have a value range of 0.2<α<0.8. The second parameter β is a parameter related to the lithium battery shell material and the installation position of the ultrasonic sensor, and its value range may be 0.6<β<1.2.

[0101] S204: Determine a passband adjustment range of the target filter based on the determined multiple characteristic frequencies, the parameters of the lithium battery, and the first proportional coefficient.

[0102] In some embodiments of the present specification, determining the passband adjustment range of the target filter based on the determined multiple characteristic frequencies, the parameters of the lithium battery, and the first proportional coefficient may include: determining the maximum passband width of the target filter based on the first proportional coefficient and the maximum value of the multiple characteristic frequencies; measuring the third output signal of the ultrasonic sensor provided on the surface of lithium batteries of different lithium battery models; determining the value range of the characteristic frequency of the third output signal corresponding to each lithium battery model; determining the second proportional coefficient between the passband adjustment range and the maximum passband width based on the value range and preset characteristic frequency distribution conditions; determining the passband adjustment range based on the second proportional coefficient, the maximum passband width, and the maximum and minimum values ​​of the multiple characteristic frequencies.

[0103] In some embodiments of the present specification, the passband adjustment range may be determined by the following formula:

[0104] Formula (2)

[0105] Among them, BW Max represents the maximum passband width of the target filter, f CMax Represents the maximum value among multiple characteristic frequencies, f CMin Represents the minimum value among multiple characteristic frequencies, f Max Indicates the maximum value of the passband adjustment range, f Min represents the minimum value of the passband adjustment range, and θ represents the second proportional coefficient between the passband adjustment range and the maximum passband width.

[0106] It can be understood that the passband adjustment range can be the range in which the passband of the target filter can be adjusted. The maximum value and the minimum value in the passband adjustment range can satisfy a certain proportional relationship with the maximum passband width, that is, the second proportional coefficient, and the second proportional coefficient can be a parameter related to the battery model.

[0107] Specifically, the second proportional coefficient θ can measure the upper and lower limits of the frequency change of the ultrasonic sensor output signal when the working state of different individuals of the same lithium battery model changes. The upper and lower limits of different individuals are normally distributed, thereby determining the value of the second proportional coefficient θ so that the passband adjustment range f Min ~f Max The 2σ range or 3σ range of the normal distribution may be covered. For example, the value range of θ may be 0.35<θ<0.65.

[0108] S205: Determine the values ​​of the parameters of the capacitor, resistor and potentiometer in the target filter based on the passband adjustment range.

[0109] Specifically, when determining other parameters of the filter module, any second-order active filter module (including a second-order active low-pass filter module and a second-order active high-pass filter module) can be adjusted through a potentiometer to meet the preset requirements for the range and sensitivity of the cut-off frequency, that is, for any second-order active filter module, if its adjustable cut-off frequency range is f1~f2, it should be:

[0110] Formula (3)

[0111] Among them, R, C, R Max It can represent the resistance value, capacitance value and the maximum resistance value of the potentiometer respectively.

[0112] In some embodiments of the present specification, after determining the passband adjustment range of the target filter based on the determined multiple characteristic frequencies, the parameters of the lithium battery, and the first proportional coefficient, it can also include: determining multiple passband ranges based on the passband adjustment range; adjusting the quality factor corresponding to each passband range, and determining whether the quality factor corresponding to each passband range meets the preset conditions based on the adjustment result; if it is determined that the quality factor corresponding to any passband range does not meet the preset conditions, adjusting the parameters of the target filter; the parameters of the target filter include at least one of the following: passband width, passband adjustment range, capacitance value, resistance value, and parameter value of the potentiometer. Among them, the preset conditions may include a threshold range corresponding to the quality factor, and the quality factor can be adjusted by adjusting the passband ripple, frequency selection factor, filter gain, etc.

[0113] Specifically, the passband range is set within the adjustable range f Min ~f Max The reasonable position of the inner complex number at least includes the boundary and the median, that is, if the passband range is f BL ~ f BH , the passband width is BW, and the passband can be set in the following three or more positions:

[0114] Formula (4)

[0115] Among them, BW can represent the passband width, f BL1 、f BH1 Respectively represent the lower cutoff frequency and upper cutoff frequency in the passband range of the first position, f BL2 、f BH2 Respectively represent the lower and upper cutoff frequencies in the passband range of the second position, f BL3 、f BH3Respectively represent the lower and upper cutoff frequencies in the passband range of the third position.

[0116] Since the quality factor Q can be determined by the resistance value of the in-phase proportional amplifier part, the resistance value of the in-phase proportional amplifier part of the second-order active filter module can be adjusted so that when the passband is set to the above position, the passband ripple γ Max Size and frequency selectivity factor ω s / ω p The size meets the performance indicators, and the overall gain of the filter matches the previous and subsequent circuits.

[0117] In some embodiments of the present specification, any of the second-order active filter modules are voltage-controlled voltage source filters, containing the same in-phase proportional amplification part with a gain greater than 1, so that the quality factor Q of each filter is the same, fixed and greater than 0.707; the capacitor in the contained RC filter circuit is composed of a fixed-value capacitor, and the resistor is composed of a fixed-value resistor and a potentiometer in series.

[0118] The following is a further introduction to the quality factor adjustment process.

[0119] In some embodiments of the present specification, after the passband position is set, all second-order active filter modules operate at their respective specific cutoff frequencies, and any second-order active low-pass filter module operates at a cutoff frequency f Li , should be less than the cut-off frequency f at which any second-order active high-pass filter module operates Hj ,Right now:

[0120] Formula (5)

[0121] Specifically, the cutoff frequency of the second-order active high-pass filter module and the cutoff frequency of the second-order active low-pass filter module can be made to be within each other's transition band. Under this premise, all second-order active low-pass filter modules can work at the same cutoff frequency or not, and the same applies to the second-order active high-pass filter module.

[0122] In some embodiments of the present specification, for any passband position during the adjustment process, the passband ripple γ Max Less than or equal to 1dB.

[0123] In some embodiments of the present specification, the passband position is adjusted to be suitable for a certain characteristic frequency f C When the passband cutoff frequency is f L and f H , then it should satisfy:

[0124] Formula (6)

[0125] In some embodiments of the present specification, the lowest value f of the passband adjustable range is Min ≥20kHz or higher.

[0126] In some embodiments of the present specification, the capacitance values ​​C of the two fixed-value capacitors of each second-order active filter module are equal, the resistance values ​​R of the two fixed-value resistors are equal, and the maximum resistance values ​​R of the two potentiometers are equal. Max Equal, use a mechanical device to connect the adjustment knobs of the two potentiometers, so that the two potentiometers can be adjusted synchronously, and the lead resistance value R of the two potentiometers can be maintained Set equal.

[0127] In some embodiments of the present specification, the potentiometer output characteristic adopted by the included second-order active filter module is at least one of an inverse proportional type, an exponential type or a customized function type, so that:

[0128] If x is used to mark the position of the potentiometer knob, R Set Note the lead-out resistance value of the potentiometer, then the functional relationship between the potentiometer adjustment knob position and the lead-out resistance value of the potentiometer can be recorded as:

[0129] R Set =F(x) Formula (7)

[0130] For any second-order active filter module, if the capacitance of the two fixed-value capacitors is C, the resistance of the two fixed-value resistors is R, and the maximum resistance of the two potentiometers is R Max , then the cutoff frequency f of this module is:

[0131] Formula (8)

[0132] When F(x) is at least one of an inverse proportional expression, an exponential expression or a customized function, G(x) can be made approximately linear or linear, and the potentiometer adjustment knob can adjust the cutoff frequency of the second-order active filter module approximately linearly or linearly.

[0133] In some embodiments of this specification, in order to make all the included second-order active filter modules and the operational amplifier chips used meet the requirements, when the module works at the upper limit f2 of its cut-off frequency adjustable range, the value range of the open-loop gain (OpenLoop Gain) can still be Open-LoopGain ≥ 40dB. The 40dB can also be determined according to the specific error requirements to determine the minimum open-loop gain, so that when the ideal operational amplifier model is used to design the circuit, the error meets the requirements.

[0134] In the specific implementation process, the quality factor of the filter can be adjusted by adjusting the above indicators, and the parameter design of the filter is completed when the quality factor meets the preset conditions, otherwise it is repeated. Figure 2The steps in are repeated until the quality factor meets the preset conditions.

[0135] The design process of the above filter parameters is further described below in conjunction with specific embodiments.

[0136] The second-order active filter module in this embodiment can be as follows Figure 3 As shown, Figure 3 a in is a second-order active high-pass filter module. Figure 3 The b in the figure is a second-order active low-pass filter module.

[0137] For a batch of lithium battery packs, it can be obtained from the experimental results that f CMin =35.1kHz, f CMax =89.9kHz, from the fitting relationship we get α=0.62, β=1.03, then τ=0.221. And we can analyze that θ=0.5, then we can get f Min =25.17kHz, f Max =99.83kHz.

[0138] According to the above method, the filter parameters are designed, a second-order low-pass voltage-controlled voltage source filter and a second-order high-pass voltage-controlled voltage source filter are connected in series to form a fourth-order bandpass filter, and the filter is composed of an AD8031 operational amplifier chip. After debugging, it is determined that the fixed capacitor value is 200pF, the fixed resistor value is 9.1kΩ, the maximum resistance of the potentiometer is 26.9kΩ, and the quality factor of the second-order active filter module is Q=2.22.

[0139] Using software simulation, a fourth-order bandpass filter is used to adjust the cutoff frequency of the second-order active low-pass filter module and the second-order active high-pass filter module to obtain different gains in the passband, as shown below: Figure 4 The amplitude-frequency characteristic curve shown in the figure, where the horizontal axis is frequency (Hz) and the vertical axis is gain (dB).

[0140] The amplitude-frequency characteristic curves of the passband positions obtained by software simulation are as follows: 25.178~31.697kHz, 31.590~39.992kHz, 39.905~50.237kHz, 50.195~63.245kHz, 63.183~79.621kHz and 79.644~100.237kHz Figure 5 As shown, the horizontal axis is frequency (Hz) and the vertical axis is gain (dB). At each passband position, the passband ripple is 0.0374dB, 0.0697dB, 0.0119dB, 0.0477dB, 0.2055dB, and 0.1062dB respectively. It can be understood that Figure 5The passband gains shown are only one of the possible cases. By adjusting each second-order active filter module, the gain within the passband can be changed without substantially affecting the size of the passband ripple.

[0141] Of course, if the order of the filter is increased, better performance can be obtained. The parameter design method is similar to the above steps and will not be described in detail in this specification.

[0142] Furthermore, the designed filter is integrated into the signal processing circuit of the BMS (Battery Management System), and the output port of the BMS ultrasonic sensor is connected to the input port of the signal processing circuit. After installing the BMS to one of the lithium battery packs, the characteristic signal frequency data of the lithium battery pack under the sensor installation method measured in the parameter design method is found, and f' can be obtained. CMax =31.24kHz, f' CMin =32.97kHz, so the passband position can be adjusted to 28.379~35.122kHz, so that the lithium battery ultrasonic signal can be effectively screened and the BMS completes the monitoring function.

[0143] Based on the signal processing method for lithium batteries described above, one or more embodiments of this specification also provide a signal processing device for lithium batteries. The device may include a device (including a distributed system), software (application), module, plug-in, server, client, etc. using the method described in the embodiments of this specification and a device combined with necessary implementation hardware. Based on the same innovative concept, the device in one or more embodiments provided in the embodiments of this specification is as described in the following embodiments. Since the implementation scheme and method of the device to solve the problem are similar, the implementation of the specific device in the embodiments of this specification can refer to the implementation of the aforementioned method, and the repetitions will not be repeated. As used below, the term "unit" or "module" can implement a combination of software and / or hardware for predetermined functions. Although the device described in the following embodiments is preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceived. Figure 6 FIG. 1 is a schematic diagram of a signal processing device for a lithium battery provided in an embodiment of the present specification. Figure 6 As shown, the signal processing device 600 for lithium battery may include:

[0144] The signal acquisition module 601 is used to acquire the output signal of the target ultrasonic sensor disposed on the surface of the lithium battery.

[0145] The parameter adjustment module 602 is used to transmit the output signal to the target filter, and adjust the parameters of the target filter based on the output signal and the target position of the target ultrasonic sensor on the surface of the lithium battery; wherein the value range corresponding to the parameters of the target filter is determined based on the historical output signal of the ultrasonic sensor provided on the surface of the lithium battery.

[0146] The signal processing module 603 is used to filter the output signal using the adjusted target filter to obtain a filtered signal, and transmit the filtered signal to the lithium battery management system to monitor the lithium battery.

[0147] In some embodiments of the present specification, the above-mentioned device may also include a parameter design module, which can be specifically used to: obtain multiple historical output signals of an ultrasonic sensor provided on the surface of a lithium battery, wherein the multiple historical output signals are signals collected and output by the ultrasonic sensor at multiple positions on the surface of the lithium battery; process the multiple historical output signals to determine the characteristic frequencies of each historical output signal; determine a first proportional coefficient between the passband width of the target filter and the characteristic frequency based on the determined multiple characteristic frequencies and the parameters of the lithium battery; determine a passband adjustment range of the target filter based on the determined multiple characteristic frequencies, the parameters of the lithium battery, and the first proportional coefficient; and determine the values ​​of the parameters of the capacitor, resistor, and potentiometer in the target filter based on the passband adjustment range.

[0148] In some embodiments of the present specification, when the parameter design module determines the first proportional coefficient between the passband width of the target filter and the characteristic frequency based on the determined multiple characteristic frequencies and the parameters of the lithium battery, it can be used to: collect the first output signal of the ultrasonic sensor under different characteristic frequencies and different lithium battery operating conditions; collect the second output signal of the ultrasonic sensor under different lithium battery parameters, different installation positions and different lithium battery working conditions; determine the maximum value among the multiple characteristic frequencies; determine the first proportional coefficient based on the first output signal, the second output signal and the maximum value.

[0149] In some embodiments of the present specification, when the parameter design module determines the first proportionality coefficient based on the first output signal, the second output signal and the maximum value, it can be used to: determine the first frequency variation range of the ultrasonic sensor output signal that changes with the working state of the lithium battery at different characteristic frequencies based on the first output signal; obtain the first relationship between the characteristic frequency and the first parameter in the preset function satisfied by the first proportionality coefficient by fitting based on the first frequency variation range, and determine the value of the first parameter corresponding to the maximum value based on the maximum value and the first relationship; determine the second frequency variation range of the ultrasonic sensor output signal that changes with the working state of the lithium battery under different lithium battery parameters and different installation positions based on the second output signal; determine the second relationship between the lithium battery parameters, the installation position and the second parameter of the preset function based on the second frequency variation range by using a cluster analysis method, and determine the value of the second parameter based on the second relationship; determine the first proportionality coefficient based on the value of the first parameter, the value of the second parameter and the preset function.

[0150] In some embodiments of this specification, the first proportionality coefficient may be determined by the following formula:

[0151] τ = αe -β ;

[0152] Among them, τ represents the first proportional coefficient, α represents the first parameter in the preset function satisfied by the first proportional coefficient, β represents the second parameter in the preset function satisfied by the first proportional coefficient, and the first parameter and the second parameter are determined based on the first output signal, the second output signal and the maximum value.

[0153] In some embodiments of the present specification, when the parameter design module determines the passband adjustment range of the target filter based on the determined multiple characteristic frequencies, the parameters of the lithium battery, and the first proportional coefficient, it can be used to: determine the maximum passband width of the target filter based on the first proportional coefficient and the maximum value of the multiple characteristic frequencies; measure the third output signal of the ultrasonic sensor provided on the surface of lithium batteries of different lithium battery models; determine the value range of the characteristic frequency of the third output signal corresponding to each lithium battery model; determine the second proportional coefficient between the passband adjustment range and the maximum passband width based on the value range and preset characteristic frequency distribution conditions; determine the passband adjustment range based on the second proportional coefficient, the maximum passband width, and the maximum and minimum values ​​of multiple characteristic frequencies.

[0154] In some embodiments of the present specification, the passband adjustment range may be determined by the following formula:

[0155] ;

[0156] Among them, BW Max represents the maximum passband width of the target filter, f CMax Represents the maximum value among multiple characteristic frequencies, f CMin Represents the minimum value among multiple characteristic frequencies, f Max Indicates the maximum value of the passband adjustment range, f Min represents the minimum value of the passband adjustment range, and θ represents the second proportional coefficient between the passband adjustment range and the maximum passband width.

[0157] In some embodiments of the present specification, the parameter design module can also be used to: determine multiple passband ranges based on the passband adjustment range; adjust the quality factor corresponding to each passband range, and determine whether the quality factor corresponding to each passband range meets the preset conditions based on the adjustment result; if it is determined that the quality factor corresponding to any passband range does not meet the preset conditions, adjust the parameters of the target filter; the parameters of the target filter include at least one of the following: passband width, passband adjustment range, capacitance value, resistance value and parameter value of potentiometer.

[0158] In some embodiments of the present specification, the target filter may include at least one second-order active low-pass filter module and at least one second-order active high-pass filter module connected in series.

[0159] In some embodiments of the present specification, the second-order active low-pass filter module and / or the second-order active high-pass filter module may include a potentiometer, and the output characteristic of the potentiometer is one of the following: inverse proportional, exponential, and preset function.

[0160] In some embodiments of the present specification, the parameter adjustment module 602 can be used to: determine at least one characteristic frequency corresponding to the output signal among the multiple characteristic frequencies based on the target position; determine the variation range of the at least one characteristic frequency, and adjust the parameters of the potentiometer in the target filter based on the variation range of the at least one characteristic frequency so that the passband of the adjusted target filter covers the variation range of the at least one characteristic frequency.

[0161] The description and functions of the above modules can be understood by referring to the content of the signal processing method for lithium batteries, which will not be repeated here.

[0162] The present application also provides an electronic device, such as Figure 7 As shown, the electronic device may include a processor 701 and a memory 702, wherein the processor 701 and the memory 702 may be connected via a bus or other means. Figure 7 The example of connecting through bus is taken in the following.

[0163] The processor 701 may be a central processing unit (CPU). The processor 701 may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or a combination of the above chips.

[0164] The memory 702 is a non-transitory computer-readable storage medium that can be used to store non-transitory software programs, non-transitory computer executable programs and modules, such as program instructions / modules corresponding to the signal processing method for lithium batteries in the embodiment of the present invention (for example, Figure 6 The processor 701 executes various functional applications and data processing of the processor by running the non-transient software programs, instructions and modules stored in the memory 702, that is, the signal processing method for lithium battery in the above method embodiment is implemented.

[0165] The memory 702 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required by at least one function; the data storage area may store data created by the processor 701, etc. In addition, the memory 702 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some embodiments, the memory 702 may optionally include a memory remotely arranged relative to the processor 701, and these remote memories may be connected to the processor 701 via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0166] The one or more modules are stored in the memory 702, and when executed by the processor 701, perform the following signal processing method for a lithium battery:

[0167] The output signal of a target ultrasonic sensor disposed on the surface of a lithium battery is obtained; the output signal is transmitted to a target filter, and parameters of the target filter are adjusted based on the output signal and the target position of the target ultrasonic sensor on the surface of the lithium battery; wherein the value range corresponding to the parameters of the target filter is determined based on the historical output signal of the ultrasonic sensor disposed on the surface of the lithium battery; the output signal is filtered using the adjusted target filter to obtain a filtered signal, and the filtered signal is transmitted to a lithium battery management system to monitor the lithium battery.

[0168] The specific details of the above electronic device can be understood by referring to the corresponding descriptions and effects in the above method embodiments, and will not be repeated here.

[0169] The present specification also provides a computer storage medium, wherein the computer storage medium stores computer program instructions, and when the computer program instructions are executed, the steps of the above-mentioned signal processing method for lithium batteries are implemented.

[0170] Those skilled in the art can understand that the implementation of all or part of the processes in the above-mentioned embodiments can be completed by instructing the relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium, and when the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, the storage medium can be a disk, an optical disk, a read-only memory (ROM), a random access memory (RAM), a flash memory, a hard disk drive (HDD) or a solid-state drive (SSD), etc.; the storage medium can also include a combination of the above-mentioned types of memory.

[0171] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0172] The systems, devices, modules or units described in the above embodiments may be implemented by computer chips or entities, or by products with certain functions.

[0173] For the convenience of description, the above device is described in various units according to their functions. Of course, when implementing the present application, the functions of each unit can be implemented in the same or multiple software and / or hardware.

[0174] It can be known from the description of the above implementation methods that those skilled in the art can clearly understand that the present application can be implemented by means of software plus a necessary general hardware platform. Based on such an understanding, the technical solution of the present application can be essentially or partly contributed to the prior art in the form of a software product, which can be stored in a storage medium such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute certain parts of the methods of each implementation method of the present application.

[0175] The present application can be used in many general or special computer system environments or configurations, such as personal computers, server computers, handheld or portable devices, tablet devices, multiprocessor systems, microprocessor-based systems, set-top boxes, programmable consumer electronic devices, network PCs, minicomputers, mainframe computers, distributed computing environments including any of the above systems or devices, etc.

[0176] The present application may be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform specific tasks or implement specific abstract data types. The present application may also be practiced in distributed computing environments where tasks are performed by remote processing devices connected through a communication network. In a distributed computing environment, program modules may be located in local and remote computer storage media, including storage devices.

[0177] Although the present application has been described through embodiments, those skilled in the art will appreciate that there are many modifications and changes to the present application without departing from the spirit of the present application, and it is desired that the present application include these modifications and changes without departing from the spirit of the present application.

Claims

1. A signal processing method for a lithium battery, characterized in that: include: Acquire an output signal of a target ultrasonic sensor disposed on the surface of a lithium battery; The output signal is transmitted to a target filter, and parameters of the target filter are adjusted based on the output signal and the target ultrasonic sensor at a target position on the surface of the lithium battery; wherein a value range corresponding to the parameter of the target filter is determined based on a historical output signal of the ultrasonic sensor disposed on the surface of the lithium battery; The output signal is filtered using the adjusted target filter to obtain a filtered signal, and the filtered signal is transmitted to a lithium battery management system to monitor the lithium battery.

2. The signal processing method for lithium battery according to claim 1, characterized in that: The value range corresponding to the parameters of the target filter is determined by: Acquire multiple historical output signals of an ultrasonic sensor disposed on the surface of the lithium battery, wherein the multiple historical output signals are signals collected and output by the ultrasonic sensor at multiple locations on the surface of the lithium battery; Processing the multiple historical output signals to determine the characteristic frequency of each historical output signal; Based on the determined multiple characteristic frequencies and the parameters of the lithium battery, determining a first proportionality coefficient between the passband width of the target filter and the characteristic frequency; Determining a passband adjustment range of the target filter based on the determined multiple characteristic frequencies, the parameters of the lithium battery, and the first proportional coefficient; Based on the passband adjustment range, the values ​​of the parameters of the capacitor, resistor and potentiometer in the target filter are determined.

3. The signal processing method for lithium battery according to claim 2, characterized in that: Based on the determined multiple characteristic frequencies and the parameters of the lithium battery, determining a first proportionality coefficient between the passband width of the target filter and the characteristic frequency includes: Collecting the first output signal of the ultrasonic sensor at different characteristic frequencies and under different lithium battery working conditions; Collect the second output signal of the ultrasonic sensor under different lithium battery parameters, different installation positions and different lithium battery working conditions; determining a maximum value among the plurality of characteristic frequencies; The first proportionality coefficient is determined based on the first output signal, the second output signal, and the maximum value.

4. The signal processing method for lithium battery according to claim 3, characterized in that: Determining the first proportionality coefficient based on the first output signal, the second output signal and the maximum value includes: Based on the first output signal, determining a first frequency variation range of the ultrasonic sensor output signal that varies with the working state of the lithium battery at different characteristic frequencies; Obtaining a first relationship between a characteristic frequency and a first parameter in a preset function satisfied by the first proportional coefficient based on fitting of the first frequency variation range, and determining a value of the first parameter corresponding to the maximum value based on the maximum value and the first relationship; Based on the second output signal, determining a second frequency variation range of the ultrasonic sensor output signal that changes with the working state of the lithium battery under different lithium battery parameters and different installation positions; Based on the second frequency variation range, a second relationship between the lithium battery parameter, the installation position and the second parameter of the preset function is determined by using a cluster analysis method, and a value of the second parameter is determined based on the second relationship; The first proportional coefficient is determined based on the value of the first parameter, the value of the second parameter and the preset function.

5. The signal processing method for lithium battery according to claim 3 or 4, characterized in that: The first proportionality coefficient is determined by the following formula: τ=αe -β ; Among them, τ represents the first proportional coefficient, α represents the first parameter in the preset function satisfied by the first proportional coefficient, β represents the second parameter in the preset function satisfied by the first proportional coefficient, and the first parameter and the second parameter are determined based on the first output signal, the second output signal and the maximum value.

6. The signal processing method for lithium battery according to claim 2, characterized in that: Determining a passband adjustment range of the target filter based on the determined multiple characteristic frequencies, the parameters of the lithium battery, and the first proportional coefficient includes: Determining a maximum passband width of the target filter based on the first proportionality coefficient and a maximum value of the plurality of characteristic frequencies; Measuring a third output signal of an ultrasonic sensor disposed on the surface of lithium batteries of different lithium battery models; Determine the value range of the characteristic frequency of the third output signal corresponding to each lithium battery model; Based on the value range and the preset characteristic frequency distribution condition, determining a second proportionality coefficient between the passband adjustment range and the maximum passband width; The passband adjustment range is determined based on the second proportionality coefficient, the maximum passband width, and the maximum and minimum values ​​of a plurality of characteristic frequencies.

7. The signal processing method for lithium battery according to claim 6, characterized in that: The passband adjustment range is determined by the following formula: ； Among them, BW Max represents the maximum passband width of the target filter, f CMax Represents the maximum value among multiple characteristic frequencies, f CMin Represents the minimum value among multiple characteristic frequencies, f Max Indicates the maximum value of the passband adjustment range, f Min represents the minimum value of the passband adjustment range, and θ represents the second proportional coefficient between the passband adjustment range and the maximum passband width.

8. The signal processing method for lithium battery according to claim 2, characterized in that: After determining the passband adjustment range of the target filter based on the determined multiple characteristic frequencies, the parameters of the lithium battery, and the first proportional coefficient, the method further includes: determining a plurality of passband ranges based on the passband adjustment range; Adjusting the quality factor corresponding to each passband range, and determining whether the quality factor corresponding to each passband range meets a preset condition based on the adjustment result; When it is determined that the quality factor corresponding to any passband range does not meet the preset conditions, the parameters of the target filter are adjusted; the parameters of the target filter include at least one of the following: passband width, passband adjustment range, capacitance value, resistance value and parameter value of potentiometer.

9. The signal processing method for lithium battery according to claim 1 or 2, characterized in that: The target filter includes at least one second-order active low-pass filter module and at least one second-order active high-pass filter module connected in series.

10. The signal processing method for lithium battery according to claim 9, characterized in that: The second-order active low-pass filter module and / or the second-order active high-pass filter module comprises a potentiometer, and the output characteristic of the potentiometer is one of the following: inverse proportional, exponential, and preset function.

11. The signal processing method for lithium battery according to claim 2, characterized in that: Adjusting the parameters of the target filter based on the output signal and the target position of the target ultrasonic sensor on the surface of the lithium battery includes: determining at least one characteristic frequency corresponding to the output signal from among the plurality of characteristic frequencies based on the target position; The variation range of the at least one characteristic frequency is determined, and the parameters of the potentiometer in the target filter are adjusted based on the variation range of the at least one characteristic frequency, so that the passband of the adjusted target filter covers the variation range of the at least one characteristic frequency.

12. A signal processing device for a lithium battery, characterized in that: include: A signal acquisition module, used to acquire an output signal of a target ultrasonic sensor disposed on the surface of the lithium battery; A parameter adjustment module, used for transmitting the output signal to a target filter, and adjusting the parameters of the target filter based on the output signal and the target position of the target ultrasonic sensor on the surface of the lithium battery; wherein the value range corresponding to the parameter of the target filter is determined based on the historical output signal of the ultrasonic sensor provided on the surface of the lithium battery; The signal processing module is used to filter the output signal using the adjusted target filter to obtain a filtered signal, and transmit the filtered signal to the lithium battery management system to monitor the lithium battery.

13. An electronic device, characterized in that: include: A memory and a processor, wherein the processor and the memory are communicatively connected to each other, the memory stores computer instructions, and the processor implements the steps of the method according to any one of claims 1 to 11 by executing the computer instructions.

14. A computer storage medium, characterized in that: The computer storage medium stores computer program instructions, and when the computer program instructions are executed, the steps of the method according to any one of claims 1 to 11 are implemented.

15. A computer program product, characterized in that The invention comprises a computer program, which implements the steps of the method according to any one of claims 1 to 11 when being executed by a processor.

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