A method and device for detecting short circuit of solid-state battery

Abstract

The present invention belongs to the field of battery manufacturing and detection, and discloses a detection method and device for solid-state battery short circuit, the method comprising: setting the range of a first current and a second current; using the first current and the second current in turn to test the charge and discharge performance of the solid-state battery; setting the numerical range of the time interval for data sampling, and sampling the voltage of the solid-state battery at equal time intervals during the process of testing the charge and discharge performance of the solid-state battery; calculating the charge and discharge characteristic parameters of the solid-state battery according to the voltage sampling result, and drawing a curve of the voltage change of the solid-state battery over time; obtaining the qualified threshold value of the charge and discharge characteristic parameters of the solid-state battery, and judging whether the charge and discharge characteristic parameters of the solid-state battery to be detected are within the qualified threshold value range of the charge and discharge characteristic parameters of the solid-state battery; if so, judging that the solid-state battery to be detected is normal, if not, judging that the solid-state battery to be detected is short-circuited. The present invention does not rely on specific temperature conditions for testing.

Description

Technical Field

[0001] The present invention relates to the field of battery manufacturing and detection, and in particular to a method and device for detecting short circuit of a solid-state battery. Background Art

[0002] With the development of battery materials, processes and other technologies, solid-state batteries are considered to be one of the important directions for the development of next-generation batteries. Compared with liquid batteries, solid-state batteries have the advantages of high safety, high energy density, high power characteristics, and long life. The manufacturing process of liquid batteries is to first assemble the positive electrode, negative electrode, and separator into a battery cell, then conduct a short-circuit test on the battery cell, and finally inject liquid into the battery. The manufacturing process of solid-state batteries is to directly assemble the positive electrode, negative electrode, and solid electrolyte into a battery, and then conduct a short-circuit test. Before the liquid battery is injected with liquid, the battery cell capacity is small, while after the solid-state battery is assembled, the capacity is larger, so the traditional liquid battery short-circuit test method cannot be used to test the solid-state battery.

[0003] At present, there are relatively few methods for detecting short circuits in solid-state batteries. In the prior art, there is a method of determining whether a solid-state battery is short-circuited by detecting the leakage current of the battery. However, the disadvantages of the prior art are that since the leakage current of the battery is small, it must be detected at a specific critical temperature to eliminate the influence of the solid electrolyte caused by the conductive ions. The detection method is cumbersome and unstable. Therefore, there is an urgent need for a method and device for detecting short circuits in solid-state batteries to meet the production detection needs of solid-state batteries. Summary of the invention

[0004] The embodiments of the present invention provide a method and device for detecting a short circuit of a solid-state battery, so as to solve the problem in the prior art that detection must be performed at a specific critical temperature due to a small leakage current of the battery.

[0005] In order to have a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. This summary is not a general review, nor is it intended to identify key / important components or to describe the scope of protection of these embodiments. Its only purpose is to present some concepts in a simple form as a prelude to the detailed description that follows.

[0006] According to a first aspect of an embodiment of the present invention, a method for detecting a short circuit of a solid-state battery is provided.

[0007] In one embodiment, a method for detecting a short circuit of a solid-state battery includes:

[0008] Based on the short-circuit glitch fusing condition of the solid-state battery, the range of the first current and the second current are set; the charging and discharging performance of the solid-state battery is tested by using the first current and the second current in sequence;

[0009] The numerical range of the time interval for data sampling is set, and in the process of testing the charge and discharge performance of the solid-state battery, the voltage of the solid-state battery is sampled at equal time intervals; based on the voltage sampling results, the charge and discharge characteristic parameters of the solid-state battery are calculated, and a curve of the voltage change of the solid-state battery over time is plotted;

[0010] Obtain the qualified threshold value of the charge and discharge characteristic parameters of the solid-state battery, and determine whether the charge and discharge characteristic parameters of the solid-state battery to be tested are within the qualified threshold range of the charge and discharge characteristic parameters of the solid-state battery; if so, determine that the solid-state battery to be tested is normal; if not, determine that the solid-state battery to be tested is short-circuited.

[0011] In one embodiment, based on the short circuit glitch fusing condition of the solid-state battery, setting the range of the first current and the second current includes:

[0012] Set the charging current value and charge the solid-state battery; sample the solid-state battery voltage at equal time intervals within a fixed time to obtain the solid-state battery voltage and sampling time;

[0013] Using the solid-state battery voltage and sampling time, calculate the charging voltage slope of the solid-state battery, as well as the average value and standard deviation of the charging voltage slope;

[0014] Determine whether the standard deviation of the charging voltage slope is less than or equal to the standard deviation threshold. If not, a short-circuit glitch exists, and the charging current value is increased step by step. If so, the short-circuit glitch is blown, and the current charging current value is determined to be the critical current value for the glitch to blow;

[0015] A first multiple of the critical current value is taken as the first current, and a second multiple of the critical current value is taken as the second current.

[0016] In one embodiment, the first multiple and the second multiple are both greater than zero, and the first multiple is smaller than the second multiple.

[0017] In one embodiment, when determining whether the standard deviation of the charging voltage slope is less than or equal to a standard deviation threshold, the standard deviation threshold range is less than 0.5.

[0018] In one embodiment, testing the charge and discharge performance of the solid-state battery using the first current and the second current in sequence includes:

[0019] The first current is used to test the charging, voltage maintenance and discharge performance of the solid-state battery; the second current is used to test the charging, voltage maintenance, self-discharge and discharge performance of the solid-state battery.

[0020] In one embodiment, calculating the charge and discharge characteristic parameters of the solid-state battery according to the voltage sampling result includes:

[0021] Calculate the absolute difference between the maximum and average values ​​of the charging slope, the holding slope, the self-discharge slope, and the discharge slope;

[0022] Calculate the charging slope, holding slope, self-discharge slope, and standard deviation of the discharge slope.

[0023] In one embodiment, when obtaining the qualified threshold of the charge and discharge characteristic parameters of the solid-state battery, the qualified threshold of the charge and discharge characteristic parameters of the solid-state battery is obtained by obtaining the statistical value of the qualified solid-state battery charge and discharge characteristic parameters.

[0024] According to a second aspect of an embodiment of the present invention, a device for detecting a short circuit of a solid-state battery is provided.

[0025] In one embodiment, the detection device for a solid-state battery short circuit comprises: a solid-state battery short circuit tester;

[0026] Solid-state battery short circuit tester includes:

[0027] The charging and discharging path switching module is used to control the opening and closing of the charging and discharging circuits; the programmable constant current charging module is used to charge and maintain the voltage of the solid-state battery; the programmable constant current discharging module is used to discharge the solid-state battery;

[0028] The sampling and processing module is used to sample the voltage of the solid-state battery at equal time intervals and upload the sampled data to the main control module;

[0029] The main control module is used to provide a start signal when testing the charge and discharge performance of the solid-state battery, and perform calculus processing on the sampled data to obtain the charge and discharge characteristic parameters of the solid-state battery and determine whether the solid-state battery is short-circuited;

[0030] The display module is used to display a curve showing the voltage of the solid-state battery changing over time.

[0031] In one embodiment, determining whether the solid-state battery is short-circuited includes:

[0032] Obtain the qualified threshold value of the charge and discharge characteristic parameters of the solid-state battery, and determine whether the charge and discharge characteristic parameters of the solid-state battery to be tested are within the qualified threshold range of the charge and discharge characteristic parameters of the solid-state battery; if so, determine that the solid-state battery to be tested is normal; if not, determine that the solid-state battery to be tested is short-circuited.

[0033] In one embodiment, when the voltage of the solid-state battery is sampled at equal time intervals, one end of the voltage sampling connection line is connected to the positive electrode and the negative electrode of the solid-state battery, and the other end is connected to the sampling and processing module.

[0034] According to a third aspect of an embodiment of the present invention, a computer device is provided.

[0035] In some embodiments, the computer device includes a memory and a processor, the memory stores a computer program, and the processor implements the steps of the above method when executing the computer program.

[0036] According to a fourth aspect of embodiments of the present invention, a computer-readable storage medium is provided.

[0037] In one embodiment, the computer-readable storage medium stores a computer program, and the computer program implements the steps of the above method when executed by a processor.

[0038] The technical solution provided by the embodiment of the present invention may have the following beneficial effects:

[0039] The present invention tests the battery by applying current excitation and current load, without relying on specific temperature conditions; wherein the excitation current and load current are much larger than the battery leakage current and the current generated by the solid electrolyte conductive ions, so no specific temperature requirement is required, and rapid detection of battery short circuit can be achieved, greatly improving detection efficiency and reliability; dual detection of small current and large current is adopted to improve the safety of the test; two judgment criteria of the absolute difference and standard deviation between the maximum slope and the average slope are adopted to improve the accuracy of the test; and the twisted pair four-wire method is adopted to sample the battery voltage to improve the sampling accuracy of the battery voltage. It is suitable for rapid detection of internal short circuits in solid-state batteries.

[0040] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0042] Figure 1 is a flow chart of a method for detecting a short circuit of a solid-state battery according to an exemplary embodiment;

[0043] Figure 2 is a structural block diagram of a device for detecting a short circuit of a solid-state battery according to an exemplary embodiment;

[0044] Figure 3 is a schematic diagram of the structure of a computer device according to an exemplary embodiment;

[0045] Figure 4 It is a flow chart of short-circuit test of solid-state battery in specific application;

[0046] Figure 5 This is a schematic diagram of the solid-state battery short-circuit tester T1 when in use;

[0047] Figure 6 It is a flow chart for judging small current and large current of solid-state batteries. DETAILED DESCRIPTION

[0048] The following description and accompanying drawings fully illustrate the specific embodiments of this article so that those skilled in the art can practice them. The parts and features of some embodiments can be included in or replace the parts and features of other embodiments. Herein, the terms "first", "second", etc. are only used to distinguish one element from another element, without requiring or implying any actual relationship or order between these elements. In fact, the first element can also be called the second element, and vice versa. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that the structure, device or equipment including a series of elements not only include those elements, but also include other elements that are not clearly listed, or also include elements inherent to such structure, device or equipment. In the absence of more restrictions, the elements defined by the sentence "comprise one..." do not exclude the existence of other identical elements in the structure, device or equipment including the elements. Each embodiment is described in a progressive manner herein, and each embodiment focuses on the differences from other embodiments, and the same similar parts between the embodiments can be referred to each other.

[0049] The terms "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. in this document indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing this document and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of this document, unless otherwise specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a mechanical connection or an electrical connection, it can also be the internal communication of two elements, it can be a direct connection, or it can be an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0050] As used herein, the term "plurality" means two or more than two, unless otherwise specified.

[0051] In this document, the character " / " indicates that the preceding and following objects are in an "or" relationship. For example, A / B means: A or B.

[0052] In this article, the term "and / or" is a description of the association relationship between objects, indicating that three relationships may exist. For example, A and / or B means: A or B, or, A and B.

[0053] It should be understood that, although the various steps in the flow chart are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear description in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the figure may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these sub-steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0054] Each module in the device or system of the present application can be implemented in whole or in part by software, hardware, or a combination thereof. The above modules can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in a computer device in the form of software, so that the processor can call and execute operations corresponding to the above modules.

[0055] In the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0056] Figure 1 An embodiment of a method for detecting a short circuit of a solid-state battery according to the present invention is shown.

[0057] In this optional embodiment, the method for detecting a short circuit of a solid-state battery includes:

[0058] S101, based on the short circuit burr fusing condition of the solid-state battery, setting the range of the first current and the second current; using the first current and the second current in turn to test the charging and discharging performance of the solid-state battery;

[0059] S103, setting a numerical range of the time interval for data sampling, and sampling the voltage of the solid-state battery at equal time intervals during the process of testing the charge and discharge performance of the solid-state battery; calculating the charge and discharge characteristic parameters of the solid-state battery according to the voltage sampling results, and drawing a curve of the voltage change of the solid-state battery over time;

[0060] S105. Obtain the qualified threshold value of the charge and discharge characteristic parameters of the solid-state battery, and determine whether the charge and discharge characteristic parameters of the solid-state battery to be tested are within the qualified threshold range of the charge and discharge characteristic parameters of the solid-state battery; if so, determine that the solid-state battery to be tested is normal; if not, determine that the solid-state battery to be tested is short-circuited.

[0061] Figure 2 An embodiment of a detection device for short circuit of a solid-state battery according to the present invention is shown.

[0062] In this optional embodiment, the detection device for a solid-state battery short circuit includes a solid-state battery short circuit tester;

[0063] Solid-state battery short circuit tester includes:

[0064] The charge and discharge path switching module 201 is used to control the opening and closing of the charge and discharge circuit;

[0065] A programmable constant current charging module 203, used to charge and maintain the voltage of the solid-state battery;

[0066] A programmable constant current discharge module 205, used to discharge the solid-state battery;

[0067] The sampling and processing module 207 is used to sample the voltage of the solid-state battery at equal time intervals and upload the sampled data to the main control module;

[0068] The main control module 209 is used to provide a start signal when testing the charge and discharge performance of the solid-state battery, and perform calculus processing on the sampled data to obtain the charge and discharge characteristic parameters of the solid-state battery and determine whether the solid-state battery is short-circuited;

[0069] The display module 211 is used to display a curve showing the voltage of the solid-state battery changing over time.

[0070] In order to facilitate understanding of the above technical solutions of the present invention, the above technical solutions of the present invention are further described below from the perspective of architecture and principle, as follows:

[0071] 1. A small current (first current) is used to charge, maintain voltage, and discharge the solid-state battery.

[0072] 2. Large current (second current) is used to charge, maintain voltage, self-discharge and discharge the solid-state battery.

[0073] 3. The solid-state battery voltage is sampled at equal time intervals during the entire charging and discharging process, and the maximum values ​​of the charging slope, voltage holding slope, self-discharge slope, and discharge slope are calculated respectively. max ,average value mean With standard deviation devt , while drawing V - T curve; among them, V is the solid-state battery voltage, T For testing time; V - T The curve can describe a complete battery charging and discharging process.

[0074] 4. Judgment | max - mean |With standard deviation devtIs it within the threshold range of a good battery? If it is within the threshold range, it is judged as not short-circuited. If it is not within the threshold range, it is judged as short-circuited. | max - mean | is the absolute difference between the maximum slope and the average slope.

[0075] The average value is:

[0076]

[0077] The standard deviation is:

[0078]

[0079] In the formula, mean represents the average value, devt represents the standard deviation, U represents the solid-state battery voltage, T Indicates the test time. k Indicates the number of equal time interval samplings ( k =1,2,3,....., N ), N Indicates the total number of samples taken at equal time intervals.

[0080] The threshold range of good quality batteries is the statistical value of most good quality batteries. The size of this threshold is related to the battery manufacturing process and judgment criteria. For example, | max - mean |No more than 1, devt Not exceeding 0.5.

[0081] The time interval can be set according to the specific situation. For example, the time interval in the present invention is 0.1s-1s.

[0082] The charging slope is to apply a constant excitation current to charge the battery, and the solid-state battery voltage U ( T ) for time T The differential value of Ud ( T ) / dT .

[0083] The voltage holding slope is a steady-state voltage when the battery is charged to a set voltage by applying a constant excitation current, and then enters constant voltage charging. U ( T ) for time T The differential value of Ud ( T ) / dT ; Among them, the holding voltage does not exceed the maximum rated withstand voltage of the solid-state battery.

[0084] The self-discharge slope is that after charging stops, the metal impurities still remain inside the battery, causing the battery to discharge itself, and the solid-state battery voltage U ( T ) for time T The differential value of Ud ( T ) / dT .

[0085] The discharge slope is to discharge the battery with an external constant load current, and the solid-state battery voltage U ( T ) for time T The differential value of Ud ( T ) / dT .

[0086] Small current and large current tests: Considering that when the battery is in a strong short circuit state, if a large current test is directly performed, it will cause the battery to overheat, causing instability of the internal solid electrolyte, and posing a safety risk. According to the detection method, a small current test is performed first. If a strong short circuit state exists, it can be directly identified and judged. If a weak short circuit state exists, the success rate of small current detection is not high, so a large current test is performed for identification and judgment.

[0087] The heat generated by the small current for charging cannot thermally fuse the short-circuit burrs, which is related to the material and process of the battery. For example, the setting range of the present invention is 10mA-250mA; when charging, the battery voltage rises slowly, and finally charges to a steady-state value and no longer changes. After stopping charging, the voltage drops rapidly.

[0088] The heat generated by charging with a large current can thermally fuse the short-circuit burr, which is related to the material and process of the battery. For example, the setting range of the present invention is 1A-20A; before the burr is thermally melted, the battery voltage rises slowly; after the burr is thermally melted, the battery voltage rises rapidly; after charging stops, since metal impurities still remain inside the battery, the self-discharge is faster than that of a good battery.

[0089] Small current and large current are statistical values ​​of most defective batteries, which are related to the manufacturing process and materials of the battery. According to the parallel shunt principle, when there is a micro short circuit inside the battery, there is leakage current between the short-circuit burrs. Before the burrs are melted, the battery charges very slowly. Ud ( T ) / dT The slope is small; after the short-circuit burr is melted, it is equivalent to eliminating the short circuit, and the battery charging speed is accelerated. Ud ( T ) / dT The slope is large, the specific method is as follows Figure 6 And the following process is shown:

[0090] 1) Setting an initial current value, which is not fixed. For example, the present invention sets the initial current value to be 10 mA.

[0091] 2) Battery charging, sampling the battery voltage at equal time intervals within a fixed time to obtain the solid-state battery voltage U ( T ), T is the sampling time, and the charging voltage slope is calculated Ud ( T ) / dT , and calculate the average mean , Standard Deviation devt ; The fixed time is not specifically fixed, for example, the present invention is set to 1 minute.

[0092] 3) Determine the average value mean , Standard Deviation devt Is there an obvious deviation? If not, the burr is not blown, and go to 4); if yes, the burr is blown, and go to 5); the standard deviation is the standard deviation devt Not more than 0.5;

[0093] 4) increasing the charging current value step by step; the step value is not fixed, for example, the step value is set to 10mA in the present invention;

[0094] 5) Determine that the current value is the critical current value for glitch fusing;

[0095] 6) Take 0.2 times of the current value as the small current value; take 5 times of the current value as the large current value.

[0096] The solid-state battery short circuit tester T1 includes: a main control module 209 (i.e., a main control module M1), a programmable constant current charging module 203 (i.e., a BUCK programmable constant current charging module P1), a programmable constant current discharging module 205 (i.e., a programmable constant current discharging module P2), a charge and discharge path switching module 201 (charge and discharge path switching module R), a sampling and processing module 207 ( V - T Sampling and processing module S1) and display module 211 (liquid crystal display module D1). Schematic diagram of the solid-state battery short circuit tester T1 of the present invention when in use, as shown in Figure 5 shown.

[0097] The specific functions are as follows:

[0098] The main control module M1 is used for the algorithm and logic control of the short circuit tester; the specific process is as follows:

[0099] During charging, the main control module M1 sends a charging start signal to the charge and discharge path switching module R and the BUCK programmable constant current charging module P1 respectively; then, the charging circuit of the charge and discharge path switching module R is turned on, and the BUCK programmable constant current charging module P1 starts to work, which charges the battery and maintains the voltage; during this process, V - T Sampling and processing module S1 for battery voltage U ( T ) to sample at equal time intervals and upload the data to the main control module M1, which will monitor the charging and pressure holding stages. U ( T ) Data is differentiated Ud ( T ) / dT , get the slope value in different time periods, and calculate the maximum value max ,average value mean , standard deviation devt At the same time, the main control module M1 collects the data U ( T ) is sent to the liquid crystal display module D1, and the liquid crystal display module D1 displays the VT curve in real time.

[0100] During self-discharge, the main control module M1 only sends a discharge start signal to the charge and discharge path switching module R;

[0101] During discharge, the main control module M1 sends a discharge start signal to the charge and discharge path switching module R and the programmable constant current discharge module P2 respectively; then, the discharge circuit of the charge and discharge path switching module R is opened, and the programmable constant current discharge module P2 starts to work, which discharges the battery; in this process, V - T Sampling and processing module S1 for battery voltage U ( T ) to sample at equal time intervals and upload the data to the main control module M1, which processes the self-discharge and discharge phases. U ( T ) Data is differentiated Ud ( T ) / dT , get the slope value in different time periods, and calculate the maximum value max ,average value mean , standard deviation devt At the same time, the main control module M1 collects the data U ( T ) is sent to the LCD module D1, and the LCD module D1 will V - T The curve is displayed in real time.

[0102] The basis for judgment is: Judgment | max - mean |With standard deviation devt Whether it is within the threshold range of good batteries. If it is within the threshold range, it is judged as not short-circuited. If it is not within the threshold range, it is judged as short-circuited. The threshold range of good batteries is the statistical value of most good batteries. The size of the threshold is related to the battery manufacturing process and the judgment standard. For example, | max - mean |No more than 1, devt Not exceeding 0.5.

[0103] BUCK programmable constant current charging module P1 can output constant voltage and constant current. After receiving the charging start signal from the main control module M1, it charges the solid-state battery with constant current and constant voltage.

[0104] The programmable constant current discharge module P2 can perform constant current discharge. After receiving the discharge start signal from the main control module M1, it performs constant current discharge on the solid-state battery.

[0105] The charge and discharge path switching module R includes a charging circuit path and a discharging circuit path. When receiving a charging start signal from the main control module M1, the charging circuit path is opened, and the charging current of the BUCK programmable constant current charging module P1 enters the battery through the path; when receiving a discharging start signal from the main control module M1, the discharging circuit path is opened, and the discharging current of the battery enters the programmable constant current discharging module P2 through the path;

[0106] V - T The sampling and processing module S1 includes an AD sampling circuit and a DA setting circuit. The main control module M1 sends the set output voltage and current values ​​to the V - T Sampling and processing module S1, V - T The DA setting circuit of the sampling and processing module S1 converts the digital signal into an analog signal and sends it to the BUCK programmable constant current charging module P1 and the programmable constant current discharging module P2; at the same time, V - T The AD sampling circuit of the sampling and processing module S1 samples the output voltage and current, and then uploads them to the main control module M1, with a sampling accuracy of 1mV and 1mA;

[0107] The LCD display module D1 can communicate with the main control module M1 to upload the external input value to the main control module M1. At the same time, it can receive the data processed by the main control module M1 for battery voltage V - T Display of curves.

[0108] In order to facilitate understanding of the present invention, the present invention is described comprehensively.

[0109] The specific connection method is as follows:

[0110] BUCK programmable constant current charging module P1 input connection V - T The sampling and processing module S1 outputs a charging circuit path connected to the charging and discharging path switching module R;

[0111] Input connection of programmable constant current discharge module P2 V - T The sampling and processing module S1 outputs a discharge circuit path connected to the charge and discharge path switching module R;

[0112] One end of the charge and discharge path switching module R is connected to the "+" and "-" of the solid-state battery BAT, and the other end is connected to the BUCK programmable constant current charging module P1 and the programmable constant current discharging module P2;

[0113] V - T One end of the sampling and processing module S1 is connected to the BUCK programmable constant current charging module P1 and the programmable constant current discharging module P2, and the other end is connected to the main control module M1;

[0114] The LCD display module D1 is connected to the main control module M1, which can set the charge and discharge voltage and current, and display the curves of the charge and discharge voltage and current;

[0115] Main control module M1 and V - T The sampling and processing module S1 is connected to the liquid crystal display module D1 to perform functions such as voltage and current sampling and processing, charge and discharge setting, and logic control.

[0116] like Figure 4 As shown, the specific implementation steps are as follows:

[0117] Step 1: Set a small current to charge, maintain voltage, and discharge, and sample the battery voltage at equal time intervals to obtain the battery voltage. U ( T ), T is the sampling time, and the voltage slopes of the three stages of charging, voltage maintenance and discharge are calculated. Ud ( T ) / dT .

[0118] Step 2: Calculate the maximum value of the voltage slope in the three stages of charging, voltage maintenance, and discharging. max ,average value mean , Standard Deviation devt , and calculate | max - mean |.

[0119] Step 3, judgement | max - mean |With standard deviation devt Whether it is within the threshold range of good batteries, if it is within the threshold range, proceed to the next step, if not, it is judged as a short circuit.

[0120] Step 4: Set high current charging, voltage maintenance, self-discharge, and discharge, and sample the battery voltage at equal time intervals to obtain the battery voltage. U ( T ), T is the sampling time, and the voltage slopes of the three stages of charging, voltage maintenance and discharge are calculated. Ud ( T ) / dT .

[0121] Step 5: Calculate the maximum value of the voltage slope in the four stages of charging, voltage maintenance, self-discharge, and discharge. max ,average value mean , Standard Deviation devt , and calculate | max - mean |.

[0122] Step 6, judgement | max - mean |With standard deviation devt Whether it is within the threshold range of good batteries, if it is within the threshold range, it is judged as not short-circuited, if not, it is judged as short-circuited.

[0123] In step four, the battery voltage is sampled using a twisted pair four-wire method. The specific method is: the output of the solid-state battery short-circuit tester T1 is connected to the solid-state battery, and the voltage is sampled not through the output line, but using two separate connecting wires, and made into a twisted pair to reduce the influence of common-mode noise. One end is connected to the "+" and "-" of the solid-state battery, and the other end is connected to the VT sampling and processing module S1, which can improve the sampling accuracy of the battery voltage.

[0124] In one embodiment, a computer device is provided. The computer device may be a server, and its internal structure diagram may be as follows: Figure 3As shown. The computer device includes a processor, a memory and a network interface connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store static information and dynamic information data. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, the steps in the above method embodiment are implemented.

[0125] Those skilled in the art will understand that Figure 3 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present invention, and does not constitute a limitation on the computer device to which the solution of the present invention is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0126] In addition, the present invention also provides a computer device, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above method embodiment when executing the computer program.

[0127] In addition, the present invention further provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps in the above method embodiment are implemented.

[0128] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided by the present invention can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory, etc. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0129] The present invention is not limited to the structures that have been described above and shown in the drawings, and various modifications and changes may be made without departing from the scope thereof.

Claims

1. A method for detecting a short circuit of a solid-state battery, characterized in that: include: Based on the short-circuit glitch fusing condition of the solid-state battery, the range of the first current and the second current are set; the charging and discharging performance of the solid-state battery is tested by using the first current and the second current in sequence; The numerical range of the time interval for data sampling is set, and in the process of testing the charge and discharge performance of the solid-state battery, the voltage of the solid-state battery is sampled at equal time intervals; based on the voltage sampling results, the charge and discharge characteristic parameters of the solid-state battery are calculated, and a curve of the voltage change of the solid-state battery over time is plotted; Obtaining a qualified threshold value of the charge and discharge characteristic parameters of the solid-state battery, and determining whether the charge and discharge characteristic parameters of the solid-state battery to be detected are within the qualified threshold range of the charge and discharge characteristic parameters of the solid-state battery; if so, determining that the solid-state battery to be detected is normal; if not, determining that the solid-state battery to be detected is short-circuited; Wherein, an excitation current and a load current are applied to the solid-state battery, and the excitation current and the load current are greater than the leakage current of the solid-state battery and the current generated by the conductive ions of the solid electrolyte; The range of setting the first current and the second current based on the short circuit glitch fusing condition of the solid-state battery includes: Set the charging current value and charge the solid-state battery; sample the solid-state battery voltage at equal time intervals within a fixed time to obtain the solid-state battery voltage and sampling time; Using the solid-state battery voltage and sampling time, calculate the charging voltage slope of the solid-state battery, as well as the average value and standard deviation of the charging voltage slope; Determine whether the standard deviation of the charging voltage slope is less than or equal to the standard deviation threshold. If not, a short-circuit glitch exists, and the charging current value is increased step by step. If so, the short-circuit glitch is blown, and the current charging current value is determined to be the critical current value for the glitch to blow; Taking a first multiple of the critical current value as the first current, and taking a second multiple of the critical current value as the second current; The first multiple and the second multiple are both greater than zero, and the first multiple is less than the second multiple; The method of sequentially using the first current and the second current to test the charge and discharge performance of the solid-state battery includes: The solid-state battery is tested using the first current to avoid overheating of the solid-state battery and to identify the state of the solid-state battery. When the solid-state battery is in a strong short-circuit state, the solid-state battery test ends. Otherwise, the solid-state battery is tested using the second current to improve the success rate of detecting the weak short-circuit state. Wherein, the first multiple is 0.2 times, and the second multiple is 5 times; The first current ranges from 10mA to 250mA, and the second current ranges from 1A to 20A; Calculating the charge and discharge characteristic parameters of the solid-state battery according to the voltage sampling result includes: Calculate the absolute difference between the maximum and average values ​​of the charging slope, the holding slope, the self-discharge slope, and the discharge slope; Calculate the standard deviation of charging slope, holding slope, self-discharge slope and discharge slope; Among them, the charging slope is the differential value of the solid-state battery voltage over time when a constant excitation current is applied to charge the solid-state battery; The voltage holding slope is the differential value of the solid-state battery voltage over time when the battery is charged to the set voltage with an external constant excitation current and enters the steady-state voltage of constant voltage charging; The self-discharge slope is the differential value of the solid-state battery voltage over time after charging stops; The discharge slope is the differential value of the solid-state battery voltage over time when a constant load current is applied to discharge the battery.

2. A method for detecting a short circuit of a solid-state battery according to claim 1, characterized in that: When determining whether the standard deviation of the charging voltage slope is less than or equal to a standard deviation threshold, the standard deviation threshold range is less than 0.

5.

3. A method for detecting a short circuit of a solid-state battery according to claim 1, characterized in that: The method of sequentially using the first current and the second current to test the charge and discharge performance of the solid-state battery includes: The first current is used to test the charging, voltage maintenance and discharge performance of the solid-state battery; the second current is used to test the charging, voltage maintenance, self-discharge and discharge performance of the solid-state battery.

4. A method for detecting a short circuit of a solid-state battery according to claim 1, characterized in that: When obtaining the qualified threshold value of the charge and discharge characteristic parameter of the solid-state battery, the qualified threshold value of the charge and discharge characteristic parameter of the solid-state battery is obtained by obtaining the statistical value of the qualified solid-state battery charge and discharge characteristic parameter.

5. A detection device for a solid-state battery short circuit, used to implement a detection method for a solid-state battery short circuit according to claim 1, characterized in that: Includes solid-state battery short-circuit tester; The solid-state battery short-circuit tester comprises: The charging and discharging path switching module is used to control the opening and closing of the charging and discharging circuits; the programmable constant current charging module is used to charge and maintain the voltage of the solid-state battery; the programmable constant current discharging module is used to discharge the solid-state battery; The sampling and processing module is used to sample the voltage of the solid-state battery at equal time intervals and upload the sampled data to the main control module; The main control module is used to provide a start signal when testing the charge and discharge performance of the solid-state battery, and perform calculus processing on the sampled data to obtain the charge and discharge characteristic parameters of the solid-state battery and determine whether the solid-state battery is short-circuited; The display module is used to display a curve showing the voltage of the solid-state battery changing over time.

6. A short circuit detection device for solid-state batteries according to claim 5, characterized in that: The determining whether the solid-state battery is short-circuited includes: Obtain the qualified threshold value of the charge and discharge characteristic parameters of the solid-state battery, and determine whether the charge and discharge characteristic parameters of the solid-state battery to be tested are within the qualified threshold range of the charge and discharge characteristic parameters of the solid-state battery; if so, determine that the solid-state battery to be tested is normal; if not, determine that the solid-state battery to be tested is short-circuited.

7. A short circuit detection device for solid-state batteries according to claim 6, characterized in that: When the voltage of the solid-state battery is sampled at equal time intervals, one end of the voltage sampling connection line is connected to the positive electrode and the negative electrode of the solid-state battery, and the other end is connected to the sampling and processing module.

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