Battery self-discharge detection device
By combining pressure, internal resistance, and thick data detection modules in the battery self -discharge detection device, the problem of being unable to accurately analyze the existing technology and the problem of internal short circuit covering the metal foreign body and directly prove the internal short circuit. promote.
Patent Information
- Application Number
- CN202420022883.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-04
- Publication Date
- 2025-01-24
- Estimated Expiration
- 2034-01-04
AI Technical Summary
The existing battery self-discharge detection device cannot accurately analyze metal foreign matter covered by other substances, and cannot directly prove that the short circuit in the diaphragm is shortened, resulting in low detection accuracy.
Provide a battery self -discharge detection device, including pressure mechanisms, resistance testing agencies, pressure measurement agencies, displacement measurement agencies, and detection modules. By applying pressure and measurement of internal resistance and thickness data, the classification results of short circuit in the battery are directly judged.
The accuracy of the battery self -discharge detection is achieved, and there is no need to make an precipitation metal foreign body detection. It directly judges the short circuit in the local area and improves the reliability of the detection.
Smart Images
Figure CN222394144U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of electrochemical batteries, and in particular to a battery self-discharge detection device. Background Art
[0002] At present, the detection and evaluation of battery self-discharge is generally carried out in the following ways: 1. Disassemble the battery; 2. Scan the pole piece or diaphragm with laser irradiation; 3. Collect plasma light; 4. Analyze the collected spectrum to determine the type of foreign matter on the pole piece or diaphragm. Therefore, LIBS (Laser-Induced Breakdown Spectroscopy) is used to compare the spectra of normal diaphragms and failed diaphragms to determine the type of foreign matter, and quantitative analysis can be performed based on the area of the spectrum line; relying on dedicated equipment can reduce the errors caused by operators and improve reproducibility.
[0003] Generally, this technology uses the principle of LIBS to perform elemental analysis on the laser irradiated area, but this technology uses a high-density laser beam to irradiate the surface of the sample, so that the surface components evaporate after passing through the plasma; therefore, the detected elements are only those near the surface; if the metal foreign matter that causes the low voltage is obviously exposed, it can be accurately analyzed by this technology. However, if the surface of the foreign matter is covered by other substances such as carbon powder or positive electrode active materials, it will make it impossible to accurately analyze the composition of the foreign matter. Usually, when the diaphragm and the pole piece are separated after disassembling the battery cell, part of the pole piece material will adhere to the diaphragm, and usually the foreign matter is completely covered, and most of the time it is impossible to directly find the metal foreign matter element.
[0004] In addition, for precipitated metal foreign matter, metal is often precipitated on both sides of the diaphragm but does not penetrate the diaphragm, which causes an internal short circuit. Therefore, the metal foreign matter on the upper and lower surfaces of the diaphragm can only be used as indirect evidence and cannot directly prove the internal short circuit of the diaphragm. The accuracy of detecting battery self-discharge is not high. Utility Model Content
[0005] The purpose of the embodiments of the present application is to provide a battery self-discharge detection device, which can achieve the technical effect of improving the accuracy of self-discharge detection.
[0006] The embodiment of the present application provides a battery self-discharge detection device, including a pressure mechanism, a resistance testing mechanism, a pressure measuring mechanism, a displacement measuring mechanism and a detection module;
[0007] The pressure mechanism comprises a press body, a pressure regulating mechanism, a sample pressing probe and a stage, wherein the pressure regulating mechanism, the sample pressing probe and the stage are respectively installed on the press body, the battery to be tested is placed on the stage, and pressure is applied to the battery to be tested through the sample pressing probe, and the pressure regulating mechanism is installed in matching with the sample pressing probe;
[0008] One end of the resistance testing mechanism is connected to the sample pressing probe, and the other end of the resistance testing mechanism is connected to the stage;
[0009] The pressure measuring mechanism is arranged between the press body and the stage;
[0010] The displacement measuring mechanism is arranged on the sample pressing probe or the stage;
[0011] The detection module is connected to the resistance testing mechanism, the pressure measuring mechanism, and the displacement measuring mechanism respectively.
[0012] In the above implementation process, the battery self-discharge detection device places the battery to be detected on the stage, applies pressure to the battery to be detected through the pressure adjustment mechanism and the sample pressing probe, and measures through the pressure measuring mechanism to obtain the pressure data of the battery to be detected; obtains the internal resistance data of the battery to be detected through the resistance testing mechanism; obtains the thickness data of the battery to be detected through the displacement measuring mechanism; thus, the detection module can output the classification result of the internal short circuit of the battery to be detected according to the pressure data, thickness data and internal resistance data of the battery to be detected, thereby realizing battery self-discharge detection and evaluation; because the battery self-discharge detection device can directly determine the local internal short circuit of the battery to be detected by measuring the internal resistance of the battery to be detected, there is no need for precipitation-type metal foreign matter detection, thereby achieving the technical effect of improving the accuracy of self-discharge detection.
[0013] Furthermore, the battery pressure adjustment mechanism includes a coarse adjustment handle, which is mounted on the press body, and the distance between the sample pressing probe and the stage is adjusted by the coarse adjustment handle.
[0014] In the above implementation process, the pressure applied to the battery to be tested can be roughly adjusted by operating the coarse adjustment handle.
[0015] Furthermore, the battery pressure regulating mechanism also includes a fine-tuning knob, which is mounted on the press body and matched with the sample pressing probe via an elastic component.
[0016] In the above implementation process, the fine-tuning knob is configured with an elastic component, and the elastic component can be compressed or loosened when the fine-tuning knob is rotated, thereby achieving the effect of fine-tuning the downward pressure and finely adjusting the pressure applied to the battery to be tested.
[0017] Furthermore, the roughness of the sample pressing probe is less than 0.3 mm, and the contact surface between the sample pressing probe and the battery to be tested is circular, and the diameter of the circle is 1 mm to 2 mm.
[0018] Furthermore, the roughness of the stage is less than 0.3 mm, and the contact surface between the stage and the battery to be tested is square.
[0019] Furthermore, the battery self-discharge detection device further comprises a limit column mechanism, and the limit column mechanism is matched and installed with the loading platform.
[0020] In the above implementation process, the stage is positioned by the limit column to prevent the stage from moving or tilting during the measurement process.
[0021] Furthermore, the pressure measurement mechanism includes a piezoelectric ceramic sheet, an electrode and a shell. The piezoelectric ceramic sheet and the electrode are installed in the shell, and the piezoelectric ceramic sheet is connected to the detection module through the electrode.
[0022] Furthermore, the pressure adjustment range of the pressure adjustment mechanism is 0-100N.
[0023] Furthermore, the battery self-discharge detection device also includes a power supply mechanism, and the power supply mechanism is respectively connected to the resistance testing mechanism, the pressure measuring mechanism, the displacement measuring mechanism, and the detection module.
[0024] In the above implementation process, the resistance testing mechanism, the pressure measuring mechanism, the displacement measuring mechanism and the detection module are powered by the power supply mechanism.
[0025] Furthermore, the displacement measuring mechanism comprises an inductive displacement sensor, and the inductive displacement sensor is fixedly mounted on the sample pressing probe, and the distance between the sample pressing probe and the stage is measured by the inductive displacement sensor.
[0026] Other features and advantages disclosed in the present application will be described in the following description, or some features and advantages can be inferred or determined without doubt from the description, or can be learned by implementing the above-mentioned technology disclosed in the present application.
[0027] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS
[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.
[0029] Figure 1 A schematic diagram of the structure of a battery self-discharge detection device provided in an embodiment of the present application;
[0030] Figure 2 A schematic diagram of impedance-pressure variation provided in an embodiment of the present application;
[0031] Figure 3 A schematic diagram of thickness-pressure variation provided in an embodiment of the present application.
[0032] Figure numerals: pressure mechanism 100; press machine body 110; pressure adjustment mechanism 120; coarse adjustment handle 121; fine adjustment knob 122; sample pressing probe 130; stage 140; resistance testing mechanism 200; pressure measuring mechanism 300; displacement measuring mechanism 400; detection module 500; limit column mechanism 600; power supply mechanism 700. DETAILED DESCRIPTION
[0033] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.
[0034] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.
[0035] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.
[0036] In addition, the terms "installed", "set", "provided with", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or a point connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0037] In addition, the terms "first", "second", etc. are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise specified, "plurality" means two or more.
[0038] Generally speaking, the existing battery self-discharge detection device cannot directly find the metal foreign matter elements most of the time; this is because the existing battery self-discharge detection device uses the principle of LIBS to perform elemental analysis on the laser irradiation area, but the LIBS technology uses a high-density laser beam to irradiate the surface of the sample, so that the surface components volatilize after passing through the plasma. Therefore, the detected elements are only those near the surface. If the metal foreign matter that causes the low voltage is obviously exposed, it can be accurately analyzed by this technology. However, if the surface of the foreign matter is covered by other substances such as carbon powder or positive electrode active materials, it will make it impossible to accurately analyze the composition of the foreign matter. Usually, when the diaphragm and the pole piece are separated after disassembling the battery cell, a part of the pole piece material will adhere to the diaphragm, and the foreign matter is usually completely covered.
[0039] In addition, for precipitated metal foreign matter, metal is often precipitated on both sides of the diaphragm but does not penetrate the diaphragm, which causes an internal short circuit. Therefore, the metal foreign matter on the upper and lower surfaces of the battery diaphragm can only serve as indirect evidence and cannot directly prove an internal short circuit, so the accuracy of detecting battery self-discharge is not high.
[0040] In order to solve the technical problems raised above, the embodiment of the present application provides a battery self-discharge detection device, which can be applied to the process of battery short circuit detection, that is, self-discharge detection; the battery self-discharge detection device places the battery to be detected on the stage, applies pressure to the battery to be detected through the pressure adjustment mechanism and the sample pressing probe, and measures through the pressure measurement mechanism to obtain the pressure data of the battery to be detected; obtains the internal resistance data of the battery to be detected through the resistance testing mechanism; obtains the thickness data of the battery to be detected through the displacement measurement mechanism; thus, the detection module can output the classification result of the internal short circuit of the battery to be detected according to the pressure data, thickness data, and internal resistance data of the battery to be detected, thereby realizing battery self-discharge detection and evaluation;
[0041] See also Figure 1 , Figure 1 A schematic diagram of the structure of a battery self-discharge detection device provided in an embodiment of the present application, the battery self-discharge detection device includes a pressure mechanism 100, a resistance testing mechanism 200, a pressure measuring mechanism 300, a displacement measuring mechanism 400 and a detection module 500;
[0042] Exemplarily, the pressure mechanism 100 includes a press body 110, a pressure regulating mechanism 120, a sample pressing probe 130 and a stage 140. The pressure regulating mechanism 120, the sample pressing probe 130 and the stage 140 are respectively installed on the press body 110. The battery to be tested is placed on the stage 140. Pressure is applied to the battery to be tested through the sample pressing probe 130. The pressure regulating mechanism 120 and the sample pressing probe 130 are installed in a matching manner.
[0043] Exemplarily, the battery to be tested placed between the sample compression probe 130 and the stage 140 described in the embodiment of the present application refers to the diaphragm of the battery to be tested; it should be noted that the components of the battery to be tested that need to be tested may also be placed between the sample compression probe 130 and the stage 140, which is only used as an example and not a limitation; to avoid repetition, it will not be described below.
[0044] Exemplarily, the battery to be tested is placed between the sample pressing probe 130 and the stage 140 , and the distance between the sample pressing probe 130 and the stage 140 is adjusted by the pressure adjusting mechanism 120 , so that the pressure applied to the battery to be tested can be adjusted.
[0045] Exemplarily, one end of the resistance testing mechanism 200 is connected to the sample pressing probe 130 , and the other end of the resistance testing mechanism 200 is connected to the stage 140 ;
[0046] Exemplarily, the resistance testing mechanism 200 may be a two-probe resistance tester, which measures the local internal resistance by clamping the battery (diaphragm) to be tested from top to bottom.
[0047] Exemplarily, the pressure measuring mechanism 300 is disposed between the press body 110 and the stage 140 ; the pressure applied to the battery to be tested is measured by the pressure measuring mechanism 300 .
[0048] Exemplarily, the displacement measurement mechanism 400 is disposed on the sample pressing probe or the stage; the distance between the sample pressing probe 130 and the stage 140 is measured by the displacement measurement mechanism 400, thereby obtaining the thickness of the battery to be tested.
[0049] Exemplarily, the detection module 500 is connected to the resistance testing mechanism 200 , the pressure measuring mechanism 300 , and the displacement measuring mechanism 400 , respectively.
[0050] Exemplarily, the detection module 500 can obtain the resistance data, pressure data and thickness data of the battery to be detected respectively according to the resistance testing mechanism 200, the pressure measuring mechanism 300 and the displacement measuring mechanism 400, so as to output the classification result of the short circuit in the battery to be detected, thereby realizing the battery self-discharge detection and evaluation;
[0051] In some embodiments, the battery self-discharge detection device places the battery to be detected on the stage 140, applies pressure to the battery to be detected through the pressure adjustment mechanism 120 and the sample pressing probe 130, and measures through the pressure measuring mechanism 300 to obtain pressure data of the battery to be detected; obtains the internal resistance data of the battery to be detected through the resistance testing mechanism 200; obtains the thickness data of the battery to be detected through the displacement measuring mechanism 400; thus, the detection module 500 can output the classification result of the internal short circuit of the battery to be detected according to the pressure data, thickness data, and internal resistance data of the battery to be detected, thereby realizing battery self-discharge detection and evaluation; because the battery self-discharge detection device can directly determine the local internal short circuit of the battery to be detected by measuring the internal resistance of the battery to be detected, there is no need for precipitation-type metal foreign matter detection, thereby achieving the technical effect of improving the accuracy of self-discharge detection.
[0052] Exemplarily, an inductive displacement sensor is provided in the displacement measuring mechanism 400; the inductive displacement sensor measures the change of the position of an object based on the change of inductance. Simply put, when one coil is close to another coil, when current passes through them, the magnetic field will change, thereby causing an induced electromotive force in the other coil. The magnitude of this induced electromotive force depends on the distance between the two coils. Therefore, by measuring the changing inductance value, the change in the position of the object relative to the sensor can be determined. When a metal object approaches the sensor, it affects the induced inductance of the coil, thereby affecting the current in the coil;
[0053] Based on the above principle, the battery self-discharge detection device can measure the distance between the sensor and the stage 140 (metal material), and the diaphragm sample between the sensor and the stage will not affect the distance measurement; the inductive sensor is fixed to the sample pressing probe by a threaded nut. Reasonable explanation of the fixed position of the inductive sensor: It has been verified by experiments that the deformation of the sample pressing probe itself is very small (much smaller than the diaphragm deformation) when pressure is applied. However, the connection between the probe and the press body produces a large deformation. Therefore, the inductive sensor must be fixed on the probe.
[0054] Optionally, the measuring range of the inductive displacement sensor is 1 mm and the accuracy is 0.1 um; the inductive displacement sensor is connected to the detection module 500 via a USB interface, and the inductive displacement sensor is externally connected to a 24V DC power supply.
[0055] Exemplarily, the working principle of the resistance testing mechanism 200 is as follows: Based on Ohm's law, R=U / I, a voltage is applied to the sample, and the current is measured to obtain the sample resistance; the determination principle of the diaphragm short circuit: for a dry diaphragm sample, its resistance should be in the megohm level. If the resistance value is below 1000 ohms, it should be determined as a local short circuit.
[0056] Optionally, the frequency condition of the impedance measurement of the resistance testing mechanism 200 is 1 KHz, and the resistance testing mechanism 200 is connected to the detection module 500 via RS-232C.
[0057] Exemplarily, the battery pressure adjustment mechanism 120 includes a coarse adjustment handle 121 , which is mounted on the press body 110 , and the distance between the sample pressing probe 130 and the stage 140 is adjusted by the coarse adjustment handle 121 .
[0058] Exemplarily, by operating the coarse adjustment handle 121 , the pressure applied to the battery to be tested can be roughly adjusted.
[0059] Exemplarily, the battery pressure regulating mechanism 120 further includes a fine-tuning knob 122 , which is mounted on the press body 110 , and the fine-tuning knob 122 is matched with the sample pressing probe 130 through an elastic member.
[0060] Exemplarily, the fine-tuning knob 122 is configured with an elastic member, and the elastic member can be compressed or loosened when the fine-tuning knob 122 is rotated, thereby achieving the effect of fine-tuning the downward pressure and finely adjusting the pressure applied to the battery to be tested.
[0061] Exemplarily, the roughness of the sample pressing probe 130 is less than 0.3 mm, and the contact surface between the sample pressing probe 130 and the battery to be tested is circular, and the diameter of the circle is 1 mm to 2 mm.
[0062] Optionally, the sample pressing probe 130 has a threaded structure on its upper portion for connection with the press body 110 ; two wing-shaped structures are provided on the side of the sample pressing probe 130 , and through holes are provided on the two wings for fixing the displacement measuring mechanism 400 .
[0063] Exemplarily, the roughness of the stage 140 is less than 0.3 mm, and the contact surface between the stage 140 and the battery to be tested is square.
[0064] Exemplarily, the battery self-discharge detection device further includes a limit column mechanism 600 , and the limit column mechanism 600 is matched and installed with the stage 140 .
[0065] Exemplarily, the stage 140 is positioned by the limiting column mechanism 600 to prevent the stage 140 from moving or tilting during the measurement process.
[0066] Optionally, the limiting column mechanism 600 is made of PET.
[0067] Exemplarily, the pressure measurement mechanism 300 includes a piezoelectric ceramic sheet, an electrode and a housing. The piezoelectric ceramic sheet and the electrode are installed in the housing. The piezoelectric ceramic sheet is connected to the detection module 500 through the electrode. The working principle of the pressure measurement mechanism 300 is as follows:
[0068] The piezoelectric ceramic is the core component of the sensor, which converts external pressure into electrical signals: there is a distribution of positive and negative charges in the crystal structure of the piezoelectric ceramic. When it receives external pressure, the crystal structure is distorted, causing the redistribution of charges and generating a potential difference.
[0069] The electrodes connect the piezoelectric ceramic sheet and the external conductive component to transport the potential difference signal generated by the piezoelectric ceramic sheet to the outside;
[0070] The outer shell is used to protect the ceramic sheet and electrodes, and plays a role in fixing and supporting.
[0071] Optionally, the range and accuracy parameters of the pressure measurement mechanism 300 are as shown in the following table:
[0072]
[0073] Table 1-Parameter table of pressure measurement mechanism
[0074] Optionally, the pressure measurement mechanism 300 is connected to the detection module 500 via a USB interface; the pressure measurement mechanism 300 is externally connected to a 10V DC power supply.
[0075] Exemplarily, the pressure adjustment range of the pressure adjustment mechanism 120 is 0-100N.
[0076] Exemplarily, the battery self-discharge detection device further includes a power supply mechanism 700 , which is connected to the resistance testing mechanism 200 , the pressure measuring mechanism 300 , the displacement measuring mechanism 400 , and the detection module 500 , respectively.
[0077] Exemplarily, the resistance testing mechanism 200 , the pressure measuring mechanism 300 , the displacement measuring mechanism 400 , and the detection module 500 are powered by the power supply mechanism 700 .
[0078] Exemplarily, the displacement measuring mechanism 400 includes an inductive displacement sensor, which is fixedly mounted on the sample pressing probe 130 , and measures the distance between the sample pressing probe 130 and the stage 140 through the inductive displacement sensor.
[0079] In some implementation scenarios, the sample pressing probe 130 is made of SUS316 material with a roughness of Ra < 0.3 mm. The contact surface between the probe and the sample is circular with a diameter of 2 mm; the stage 140 is made of SUS316 material with a roughness of Ra < 0.3 mm. The contact surface with the sample is square, 60x60 mm; the resistance testing mechanism 200 uses a two-probe resistance tester; thus, the contact surface state between the sample pressing probe 130 and the sample is stable, ensuring the reliability of resistance and pressure measurement.
[0080] Exemplarily, the pressure mechanism 100 uses a manual micro press, operates a knob to apply pressure, and uses the pressure measuring mechanism 300 to measure the pressure, thereby ensuring the reliability of the pressure measurement.
[0081] Exemplarily, the displacement measurement mechanism 400 uses an inductive displacement sensor to measure the distance between the sample pressing probe 130 and the stage 140 ; the inductive sensor is fixed on the sample pressing probe 130 to ensure the reliability of the displacement measurement.
[0082] Exemplarily, the detection module 500 has built-in testing and analysis software, which acquires the resistance, pressure, and displacement data measured by the internal resistance meter, piezoelectric sensor, and inductive sensor in real time; analyzes the data according to the set conditions, and then outputs the classification results: significant short circuit points, general short circuit points, potential short circuit points, etc.
[0083] In some embodiments, the present application implements a battery self-discharge detection device, the resistance testing mechanism 200 is based on the principle of measuring resistance by a two-probe method, and the diaphragm is clamped up and down to measure the local internal resistance; the pressure mechanism 100 is used to apply pressure to the diaphragm, and the pressure measuring mechanism 300 is used to measure at the same time to obtain the change data of the diaphragm internal resistance with pressure; the displacement measuring mechanism 400 is used to measure the change of the diaphragm thickness during the process of applying pressure to the diaphragm, and the change data of the diaphragm thickness with pressure is obtained; the detection module 500 automatically obtains the pressure, thickness, and internal resistance data, and outputs the classification result of the severity of the internal short circuit caused by the metal foreign matter; thus, the battery self-discharge detection device directly determines whether the metal foreign matter causes a local internal short circuit of the diaphragm by measuring the internal resistance of the diaphragm, and since this type of internal short circuit is also called a micro short circuit, it has the characteristic of an unstable short circuit state (short and intermittent), it is necessary to apply pressure when measuring its internal resistance, obtain the internal resistance values under different pressures, and judge the severity of the short circuit and whether the short circuit state is stable; 2) Measure the change in the thickness of the diaphragm sample to assist in evaluating the presence and shape of metal foreign matter.
[0084] In some embodiments, the detection module 500 is a computer; the computer can synchronously receive signals from the resistance testing mechanism 200, the pressure measuring mechanism 300, and the displacement measuring mechanism 400; since the pressure control is manual control, the working mode of the detection module 500 is as follows:
[0085] Click the [Start] button on the operation interface at any time, and the software will start collecting impedance, pressure, and displacement data;
[0086] At this time, operate the pressure knob to adjust the pressure; after the test is completed, click the [Stop] button to stop collecting data;
[0087] The classification logic based on the measurement results varies based on the characteristics of each product. The example logic is as follows:
[0088] 1) When the pressure is 0-100kPa, the impedance is stably less than 1000 ohms, which is judged as a significant short circuit point;
[0089] 2) When the pressure is 0-100KPa, the resistance value is stably greater than 1000 ohms; when the pressure is 100K-3MPa, the resistance value is stably less than 1000 ohms, which is judged as a general short circuit point;
[0090] 3) When the pressure is 0-100KPa, the resistance value is stably greater than 1000 ohms; when the pressure is 100K-3MPa, the resistance value jumps and becomes less than 1000 ohms, which is judged as a potential short circuit point;
[0091] The correlation between displacement and short circuit degree is complex and can be flexibly used in short circuit degree judgment and short circuit mechanism analysis. The detailed description thereof is omitted in the embodiments of the present application.
[0092] In some embodiments, in combination Figure 1 The battery self-discharge detection device shown in the figure has a specific test process example as follows:
[0093] 1. Place the membrane samples 1, 2, and 3 to be tested in a vacuum oven and dry them at 60°C for 6 hours;
[0094] 2. Wipe the stage and the clamping probe with 1) DMC and 2) anhydrous alcohol to ensure that no foreign matter remains;
[0095] 3. Place the sample on the stage and use a handheld CCD microscope to confirm the location of the abnormal point. Then press down the press handle to fix the sample;
[0096] 4. Confirm the pressure value on the software interface, which is within the range of 0-20KPa, and then click [Start];
[0097] 5. Operate the pressure knob to gradually increase the pressure. When the pressure value on the software interface is greater than 3MPa (or the upper limit of the test condition), click [Stop] to stop collecting data. The data (CSV file) is automatically saved to the specified path;
[0098] 6. Open the data file on the analysis software and display the judgment results after batch processing: samples 1, 2, and 3 are significant short-circuit points, one-plate short-circuit points, and potential short-circuit points respectively;
[0099] 7. The original data is processed in Excel to obtain the following results: Figure 2 , 3 shown.
[0100] In all the embodiments of the present application, "big" and "small" are relative, "more" and "less" are relative, and "up" and "down" are relative. The expressions of such relative terms are not elaborated in the embodiments of the present application.
[0101] It should be understood that the "in this embodiment", "in the embodiment of the present application" or "as an optional implementation" mentioned throughout the specification means that the specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present application. Therefore, "in this embodiment", "in the embodiment of the present application" or "as an optional implementation" appearing throughout the specification does not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. Those skilled in the art should also be aware that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily required for the present application.
[0102] In the various embodiments of the present application, it should be understood that the size of the serial numbers of the above-mentioned processes does not necessarily mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.
[0103] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.
Claims
1. A battery self-discharge detection device, characterized in that: It includes a pressure mechanism, a resistance testing mechanism, a pressure measuring mechanism, a displacement measuring mechanism and a detection module; The pressure mechanism comprises a press body, a pressure regulating mechanism, a sample pressing probe and a stage, wherein the pressure regulating mechanism, the sample pressing probe and the stage are respectively installed on the press body, the battery to be tested is placed on the stage, and pressure is applied to the battery to be tested through the sample pressing probe, and the pressure regulating mechanism is installed in matching with the sample pressing probe; One end of the resistance testing mechanism is connected to the sample pressing probe, and the other end of the resistance testing mechanism is connected to the stage; The pressure measuring mechanism is arranged between the press body and the stage; The displacement measuring mechanism is arranged on the sample pressing probe or the stage; The detection module is connected to the resistance testing mechanism, the pressure measuring mechanism, and the displacement measuring mechanism respectively.
2. The battery self-discharge detection device according to claim 1, characterized in that: The pressure adjustment mechanism comprises a coarse adjustment handle, which is mounted on the press body, and the distance between the sample pressing probe and the stage is adjusted by the coarse adjustment handle.
3. The battery self-discharge detection device according to claim 2, characterized in that: The pressure regulating mechanism further comprises a fine-tuning knob, which is mounted on the press body and matched with the sample pressing probe via an elastic component.
4. The battery self-discharge detection device according to claim 1, characterized in that: The roughness of the sample pressing probe is less than 0.3 mm, and the contact surface between the sample pressing probe and the battery to be tested is circular, and the diameter of the circle is 1 mm to 2 mm.
5. The battery self-discharge detection device according to claim 1 or 4, characterized in that: The roughness of the stage is less than 0.3 mm, and the contact surface between the stage and the battery to be tested is square.
6. The battery self-discharge detection device according to claim 1, characterized in that: The battery self-discharge detection device further comprises a limit column mechanism, and the limit column mechanism is matched and installed with the loading platform.
7. The battery self-discharge detection device according to claim 1, characterized in that: The pressure measurement mechanism comprises a piezoelectric ceramic sheet, an electrode and a shell. The piezoelectric ceramic sheet and the electrode are installed in the shell, and the piezoelectric ceramic sheet is connected to the detection module through the electrode.
8. The battery self-discharge detection device according to claim 1, characterized in that: The pressure regulating range of the pressure regulating mechanism is 0-100N.
9. The battery self-discharge detection device according to claim 1, characterized in that: The battery self-discharge detection device also includes a power supply mechanism, which is respectively connected to the resistance testing mechanism, the pressure measuring mechanism, the displacement measuring mechanism, and the detection module.
10. The battery self-discharge detection device according to claim 1, characterized in that: The displacement measuring mechanism comprises an inductive displacement sensor, which is fixedly mounted on the sample pressing probe, and the distance between the sample pressing probe and the stage is measured by the inductive displacement sensor.