Battery positive electrode detection device

Abstract

The utility model provides a battery positive electrode detection device, the battery positive electrode detection device comprises a detection cylinder body, a pressure component and a base, the detection cylinder body is used for accommodating a detection sample and / or a test solvent, two ends of the detection cylinder body are respectively provided with a medium inlet and a medium outlet, and the medium inlet and the medium outlet are communicated with the detection cylinder body. The surface of the detection cylinder is provided with scale marks along the axial direction, the pressure applying assembly extends into the detection cylinder from the medium inlet and is used for extruding a detection sample, the surface of the base is provided with a groove, and the detection cylinder extends into the groove from one end of the medium outlet and is detachably connected with the base. The positive electrode liquid absorption speed, the expansion degree, the positive electrode expansion performance and the like are detected, and the problems that the compaction density of the assembled positive electrode cannot be measured, and the expansion degree of the positive electrode is unknown are solved.

Description

Technical Field

[0001] The utility model belongs to the technical field of batteries and relates to a battery positive electrode detection device. Background Art

[0002] At present, the testing methods of porous carbon positive electrodes include mechanical strength, density and other tests. Among them, the density test is mostly a loose density test, which can be used as a single-process test method for positive electrode preparation to measure the consistency of positive electrode preparation, but this performance cannot correspond to the compaction density inside the battery cell after the battery assembly process, the positive electrode expansion state and performance after the electrolyte is injected, and the expansion state and related performance of the positive electrode in the battery are closely related to the battery performance.

[0003] Therefore, it is very important to provide a detection device to detect the performance of the positive electrode after the electrolyte is injected. Utility Model Content

[0004] In view of the shortcomings of the prior art, the purpose of the utility model is to provide a battery positive electrode detection device, which can detect the positive electrode liquid absorption speed, expansion degree, positive electrode expansion performance, etc. after the electrolyte is injected, thereby solving the problem that the compaction density of the positive electrode after assembly cannot be measured and the positive electrode expansion degree is unknown.

[0005] To achieve this purpose, the utility model adopts the following technical solutions:

[0006] The utility model provides a battery positive electrode detection device, which comprises a detection cylinder, a pressure component and a base. The detection cylinder is used to accommodate a detection sample and / or a test solvent. A medium inlet and a medium outlet are respectively provided at two ends of the detection cylinder. A scale line is axially arranged on the surface of the detection cylinder. The pressure component extends into the detection cylinder from the medium inlet to squeeze the detection sample. A groove is provided on the surface of the base. The detection cylinder extends into the groove from one end of the medium outlet and is detachably connected to the base.

[0007] During the application of the battery positive electrode detection device provided by the utility model, the detection cylinder is extended from one end of the medium outlet into the groove of the base for sealing, and then the detection sample and / or the test solvent are injected into the detection cylinder from the medium inlet, and then the pressure component is extended from the medium inlet to squeeze the detection sample for testing, which can simulate the positive electrode feeding situation during the battery assembly process, and finally confirm the influence of the positive electrode compaction on the battery performance by detecting and evaluating the compaction density of the positive electrode inside the battery, the liquid absorption speed and the expansion degree of the positive electrode after the electrolyte is injected.

[0008] The battery positive electrode detection device of the utility model can simulate the positive electrode feeding situation during the battery assembly process, detect the compaction of the battery positive electrode, observe the state of the test sample after compaction, and calculate the corresponding compaction density parameters. In addition, the utility model can detect and evaluate the liquid absorption and expansion state of the compacted test sample. After adding the electrolyte, the state of the positive electrode after expansion is visually observed with the naked eye, and the expansion situation in the medium space of the actual battery assembly is confirmed by calculating the longitudinal expansion rate of the test sample under a fixed volume. In addition, the utility model also detects and evaluates the diameter expansion of the test sample taken out after compaction, confirms the lateral expansion degree of the test sample after liquid absorption, so as to confirm and measure the pressure of the test sample on the side diaphragm of the battery after liquid absorption. At the same time, the battery is tested and evaluated in combination with the compaction and expansion of the test sample, and the basic parameters after the positive electrode is compacted and absorbed are confirmed, so as to analyze the relevant electrical properties of the battery.

[0009] It should be noted that the detection cylinder described in the utility model is an internal through structure, with a medium inlet at one end and a medium outlet at the other end. The utility model does not specifically limit the structure of the pressure component, and any component that can extend from the medium inlet to the detection cylinder and apply pressure to the detection sample can be used in the utility model.

[0010] During the application process, those skilled in the art can add the test sample and / or the test solvent into the test cylinder according to the actual test situation. When performing compaction density test, only the test sample can be added into the test cylinder; when performing liquid absorption expansion test, the test sample and the test solvent can be injected into the test cylinder in sequence.

[0011] As a preferred technical solution of the utility model, the inner diameter of the detection cylinder is 5 to 50 mm.

[0012] As a preferred technical solution of the utility model, the inner diameter of the detection cylinder is 8 to 15 mm.

[0013] As a preferred technical solution of the utility model, the detection cylinder is a transparent glass cylinder.

[0014] As a preferred technical solution of the utility model, the detection cylinder is a polystyrene cylinder, a polymethyl methacrylate cylinder or a polycarbonate cylinder.

[0015] The material of the detection cylinder in the utility model is transparent glass or a polymer with high visibility, so as to observe the change of the detection sample in the detection cylinder.

[0016] As a preferred technical solution of the utility model, the inner annular wall of the groove is filled with a blocking piece along the circumferential direction.

[0017] As a preferred technical solution of the utility model, the blocking member includes a sealing ring.

[0018] During the application of the utility model, the detection cylinder is first fixed in the groove and sealed by the plugging piece, and then the detection sample is sent into the detection cylinder to prevent the detection sample from leaking or overflowing.

[0019] As a preferred technical solution of the utility model, the length of the pressure-applying assembly is greater than or equal to the length of the detection cylinder.

[0020] The utility model injects the test sample into the inner cavity of the test cylinder from the medium inlet, and the pressure component slowly moves along the test cylinder and squeezes the test sample to compact it for testing. After the base is disassembled, the pressure component is used to continue to press the compacted test sample so that it escapes from the medium outlet of the test cylinder, and then the escaped test sample is tested. In addition, the length of the pressure component of the utility model is adjustable, which is convenient for storage and assembly.

[0021] As a preferred technical solution of the utility model, the diameter of the pressure-applying component is 0.1 to 1 mm smaller than the inner diameter of the detection cylinder.

[0022] The diameter of the pressure component in the utility model is slightly smaller than the inner diameter of the detection cylinder and is adapted to the inner cavity of the detection cylinder, thereby increasing the contact area between the pressure component and the detection sample, preventing the detection sample from overflowing or splashing, and being able to evenly suppress the detection sample, which is beneficial to improving the detection accuracy.

[0023] It should be noted that the pressure component in the present invention can be pressed manually or automatically. When pressed manually, the operator manually presses the pressure component along the axial direction inside the test cylinder to squeeze the test sample. When pressed automatically, the pressure component can be driven to move by a hydraulic rod, a pneumatic rod or an electric push rod to squeeze the test sample. In addition, the present invention can also set a pressure sensor component on the pressure component to detect the downward pressure of the pressure component in real time to ensure pressure stability.

[0024] As a preferred technical solution of the utility model, a pressing handle is also provided on the pressure-applying assembly.

[0025] It should be noted that the present invention does not specifically limit the structure of the pressing handle. For example, the pressing handle may be plum blossom-shaped, cross-shaped, or straight-shaped.

[0026] Compared with the prior art, the beneficial effects of the utility model are:

[0027] In the application process of a battery positive electrode detection device provided by the utility model, the detection cylinder is extended from one end of the medium outlet into the groove of the base for sealing, and then the detection sample and / or the test solvent are injected into the detection cylinder from the medium inlet, and then the pressure component is extended from the medium inlet to squeeze the detection sample for testing, which can simulate the positive electrode feeding situation in the battery assembly process, thereby realizing the detection and evaluation of the compaction density of the positive electrode inside the battery, the liquid absorption speed and expansion degree of the positive electrode after the electrolyte is injected, so as to confirm the influence of the positive electrode compaction on the battery performance, improve the detection accuracy of the positive electrode compaction density and the positive electrode expansion degree, and obtain a battery with excellent performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic structural diagram of a battery positive electrode detection device provided in a specific embodiment of the utility model.

[0029] Figure 2 This is a schematic diagram of the discharge capacity test results of the battery provided in Example 1 of the present utility model.

[0030] Among them, 1-detection cylinder; 2-pressure component; 3-base; 4-groove; 5-sealing part; 6-pressing handle. DETAILED DESCRIPTION

[0031] It should be understood that, in the description of the present utility model, the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, which is only for the convenience of describing the present utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present utility model, unless otherwise specified, "multiple" means two or more.

[0032] It should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "disposed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0033] The technical solution of the utility model is further explained below with reference to the accompanying drawings and through specific implementation methods.

[0034] In a specific embodiment, the utility model provides a battery positive electrode detection device, such as Figure 1 As shown, it comprises a detection cylinder 1, a pressure component 2 and a base 3. The interior of the detection cylinder 1 is through and is used to accommodate a detection sample and / or a test solvent. The two ends of the detection cylinder 1 are respectively provided with a medium inlet and a medium outlet. The surface of the detection cylinder 1 is provided with scale lines along the axial direction. The pressure component 2 extends into the detection cylinder 1 from the medium inlet to squeeze the detection sample. The surface of the base 3 is provided with a groove 4. The detection cylinder 1 extends into the groove 4 from one end of the medium outlet and is detachably connected to the base 3.

[0035] The detection device of the utility model detects and evaluates the compaction density of the positive electrode inside the battery, the liquid absorption speed of the positive electrode after injecting electrolyte, and the expansion degree, and confirms the influence of the positive electrode compaction on the battery performance. The use method thereof specifically includes the following steps:

[0036] (1) Weigh a test sample with a mass of m1 and add it to a test cylinder 1 with an inner diameter of R1. Use a pressure component 2 to press the test sample down to the scale L1. Weigh a test sample with a mass of m2 and add it to the test cylinder 1. Press it down to the scale L2 (the lowest liquid level of the particles). Observe the compaction state of the test sample.

[0037] (2) Calculate the compacted density of the test sample: ρ = (L2 × πR1 2 ) / (m1+m2);

[0038] (3) Add the test solvent into the test cylinder 1 and let it stand for 30 to 45 minutes to confirm the upward expansion of the test sample. After the test sample expands, the liquid level rises to L3. At the same time, observe the squeezing state between the test sample and the inner wall of the test cylinder 1;

[0039] (4) Calculate the longitudinal expansion of the test sample - K1 = (L3-L2) / L2×100%;

[0040] (5) Remove the base 3 at the bottom of the test cylinder 1, use the pressure component 2 to push the extruded test sample out of the medium outlet end, and measure the diameter R2 of the test sample;

[0041] (6) Calculate the transverse expansion of the test sample K2 = (R2-R1) / R1;

[0042] (7) The compaction density, longitudinal expansion and transverse expansion of the test samples are theoretically analyzed, and then they are assembled into batteries for battery capacity testing to evaluate the impact of the compaction density and expansion of the test samples on battery performance.

[0043] The battery positive electrode detection device of the utility model can simulate the positive electrode feeding situation during the battery assembly process, detect the compaction of the battery positive electrode, observe the state of the test sample after compaction, and calculate the corresponding compaction density parameters. In addition, the utility model can detect and evaluate the liquid absorption and expansion state of the compacted test sample. After adding the electrolyte, the state of the positive electrode after expansion is visually observed with the naked eye, and the expansion situation in the medium space of the actual battery assembly is confirmed by calculating the longitudinal expansion rate of the test sample under a fixed volume. In addition, the utility model also detects and evaluates the diameter expansion of the test sample taken out after compaction, confirms the lateral expansion degree of the test sample after liquid absorption, so as to confirm and measure the pressure of the test sample on the side diaphragm of the battery after liquid absorption. At the same time, the battery is tested and evaluated in combination with the compaction and expansion of the test sample, and the basic parameters after the positive electrode is compacted and absorbed are confirmed, so as to analyze the relevant electrical properties of the battery.

[0044] In some embodiments, the inner diameter of the detection cylinder 1 is 5 to 50 mm, for example, it can be 5mm, 8mm, 9mm, 10mm, 12mm, 15mm, 20mm, 25mm, 28mm, 30mm, 35mm, 38mm, 40mm, 45mm, 48mm or 50mm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0045] Preferably, the inner diameter of the detection cylinder 1 is 8-15 mm, for example, 5 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm or 15 mm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0046] In some embodiments, the detection cylinder 1 is a transparent glass cylinder.

[0047] In some embodiments, the detection cylinder 1 is a polystyrene cylinder, a polymethyl methacrylate cylinder or a polycarbonate cylinder.

[0048] In some embodiments, the inner annular wall of the groove 4 is filled with a plugging member 5 along the circumferential direction. Specifically, the plugging member 5 includes a sealing ring. During application, the detection cylinder 1 is first fixed in the groove 4 and sealed with the plugging member 5, and then the detection sample is sent into the detection cylinder 1 to prevent leakage or overflow of the detection sample.

[0049] In some embodiments, the length of the pressure component 2 is greater than or equal to the length of the detection cylinder 1. The diameter of the pressure component 2 is 0.1 to 1 mm smaller than the inner diameter of the detection cylinder 1, for example, it can be 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm or 1 mm, but it is not limited to the listed values, and other values ​​not listed in this numerical range are also applicable. The diameter of the pressure component 2 is slightly smaller than the inner diameter of the detection cylinder 1 and is compatible with the inner cavity of the detection cylinder 1, which increases the contact area between the pressure component 2 and the detection sample, prevents the detection sample from overflowing or splashing, and can evenly suppress the detection sample, which is conducive to improving the detection accuracy. The detection cylinder 1 has a through structure, and the detection sample, test solvent and pressure component 2 all enter the inner cavity of the detection cylinder 1 from the medium inlet. The pressure component 2 slowly moves along the detection cylinder 1 and squeezes the detection sample to compact it for testing. After the base 3 is disassembled, the pressure component 2 is used to continue to press the compacted detection sample so that it escapes from the medium outlet of the detection cylinder 1, and then the escaped detection sample is tested.

[0050] In addition, for the convenience of storage and assembly, the length of the pressure assembly 2 of the present invention is adjustable. In order to help those skilled in the art better understand the overall technical solution and working process of the present invention, the present invention exemplarily provides the following structure of a pressure assembly 2 with adjustable length: the pressure assembly 2 includes a rod body and a sleeve, a plurality of positioning through holes are opened on the rod body along the axial direction, the sleeve is sleeved on the outer periphery of the rod body, and at least two limiting protrusions are symmetrically arranged on the inner wall of the sleeve, and the limiting protrusions can be inserted into the positioning through holes to achieve the fixation of the rod body and the sleeve. During the application process, those skilled in the art can adjust the insertion position of the limiting protrusion according to actual needs to extend or shorten the pressure assembly 2. Of course, it can be understood that other styles of pressure assemblies 2 that can achieve adjustable length also fall within the protection scope and disclosure scope of the present invention, so other forms of pressure assemblies 2 disclosed in the prior art or not disclosed in the new technology can also be used in the present invention.

[0051] The pressure component 2 in the utility model can be pressed manually or automatically. When pressed manually, the operator manually presses the pressure component 2 along the axial direction inside the detection cylinder 1 to press the test sample. When pressed automatically, the pressure component 2 can be driven to move by a hydraulic rod, a pneumatic rod or an electric push rod to press the test sample. The pressure component 2 can also be remotely controlled through software and hardware and electromechanical control technology to automatically press the test sample.

[0052] In some embodiments, a pressure sensing component is provided on the pressure-applying component 2 to detect the downward pressure of the pressure-applying component 2 in real time to ensure pressure stability.

[0053] In some embodiments, the pressure-applying assembly 2 is further provided with a pressing handle 6, which may be plum blossom-shaped, mitre-shaped, cross-shaped, or straight-shaped.

[0054] The numerical range described in the present invention not only includes the point values ​​listed above, but also includes any point values ​​between the above numerical ranges that are not listed. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0055] Example 1

[0056] The present embodiment provides a battery positive electrode detection device, including a detection cylinder 1, a pressure assembly 2 and a base 3. The detection cylinder 1 is through-internal and has an inner diameter of 8 mm. A medium inlet and a medium outlet are respectively arranged at both ends of the detection cylinder 1. Scale lines are also arranged along the axial direction on the surface of the detection cylinder 1. The pressure assembly 2 adopts a pressure rod with a diameter of 7.5 mm, which extends from the medium inlet into the detection cylinder 1 to squeeze the detection sample. A groove 4 is provided on the surface of the base 3. The detection cylinder 1 extends into the groove 4 from one end of the medium outlet and is detachably connected to the base 3. The inner annular wall of the groove 4 is filled with a sealing member 5 along the circumferential direction to seal the detection cylinder 1.

[0057] This embodiment uses a battery positive electrode detection device to detect the porous carbon positive electrode, which specifically includes the following steps:

[0058] (1) Weigh 0.1 g (denoted as m1) of the porous carbon positive electrode and add it to the detection cylinder 1 with an inner diameter of 8 mm (denoted as R1). Use the pressure component 2 to press the porous carbon positive electrode down to the scale 1.0 (denoted as L1). Weigh 0.1 g (denoted as m2) of the porous carbon positive electrode again and add it to the detection cylinder 1. Press it down to the scale 2.0 (the lowest liquid level of the particles) (denoted as L2), and observe the compaction state;

[0059] (2) Based on the formula ρ = (L2 × πR1 2 ) / (m1+m2), calculate the compaction density of the porous carbon cathode;

[0060] (3) Add ethanol solvent into the detection cylinder 1 and let it stand for 30 minutes to confirm the upward expansion of the porous carbon positive electrode. After the porous carbon positive electrode expands, the liquid level rises to 2.2 (denoted as L3). At the same time, observe the extrusion state between the porous carbon positive electrode and the inner wall of the detection cylinder 1;

[0061] (4) Based on the formula -K1 = (L3-L2) / L2×100%, the longitudinal expansion of the porous carbon positive electrode is calculated;

[0062] (5) Remove the base 3 at the bottom of the detection cylinder 1, use the pressure component 2 to push the extruded porous carbon positive electrode out of the medium outlet end, and measure the diameter R2 of the porous carbon positive electrode;

[0063] (6) Based on the formula K2 = (R2-R1) / R1, calculate the lateral expansion of the porous carbon positive electrode;

[0064] (7) The compaction density of the porous carbon positive electrode is 0.3981 g / cm 2 , the longitudinal expansion is 9.09% and the transverse expansion is 9.75%;

[0065] (8) After drying, the compacted porous carbon positive electrode with the same operation under the compaction density was assembled into a 1 / 2AA lithium thionyl chloride battery, filled with liquid and packaged, and then a room temperature 330Ω discharge capacity test was performed. The test results are as follows Figure 2 (In the figure, the horizontal axis represents the test time, and the vertical axis represents the stable voltage value).

[0066] The battery positive electrode detection device provided in this embodiment is used to detect and evaluate the porous carbon positive electrode to obtain a battery with excellent performance. Figure 2 It can be seen from the discharge curve that the stable voltage will only decrease after the battery has been discharged for 75 hours, which shows that the battery has a good capacity retention rate and strong stability.

[0067] The applicant declares that the above is only a specific implementation method of the present utility model, but the protection scope of the present utility model is not limited thereto. The technicians in the relevant technical field should understand that any changes or substitutions that can be easily thought of by the technicians in the relevant technical field within the technical scope disclosed in the present utility model fall within the protection scope and disclosure scope of the present utility model.

Claims

1. A battery positive electrode detection device, It is characterized in that The battery positive electrode detection device includes a detection cylinder, a pressure-applying assembly and a base. The detection cylinder is used to accommodate a detection sample and / or a test solvent. A medium inlet and a medium outlet are respectively provided at both ends of the detection cylinder. Scale lines are axially arranged on the surface of the detection cylinder. The pressure-applying assembly extends into the detection cylinder from the medium inlet to squeeze the detection sample. A groove is provided on the surface of the base. The detection cylinder extends into the groove from one end of the medium outlet and is detachably connected to the base.

2. The battery positive electrode detection device according to claim 1, It is characterized in that The inner diameter of the detection cylinder is 5 to 50 mm.

3. The battery positive electrode detection device according to claim 2, It is characterized in that The inner diameter of the detection cylinder is 8-15 mm.

4. The battery positive electrode detection device according to claim 1, It is characterized in that The detection cylinder is a transparent glass cylinder.

5. The battery positive electrode detection device according to claim 1, It is characterized in that The detection cylinder is a polystyrene cylinder, a polymethyl methacrylate cylinder or a polycarbonate cylinder.

6. The battery positive electrode detection device according to any one of claims 1 to 5, It is characterized in that The inner annular wall of the groove is filled with sealing pieces along the circumferential direction.

7. The battery positive electrode detection device according to claim 6, It is characterized in that The blocking member includes a sealing ring.

8. The battery positive electrode detection device according to any one of claims 1 to 5, It is characterized in that The length of the pressure-applying assembly is greater than or equal to the length of the detection cylinder.

9. The battery positive electrode detection device according to claim 1, It is characterized in that The diameter of the pressure-applying component is 0.1-1 mm smaller than the inner diameter of the detection cylinder.

10. The battery positive electrode detection device according to claim 1, It is characterized in that The pressure applying component is also provided with a pressing handle.

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