Testing device and method for detecting permeability of polar plate

Abstract

The invention relates to a test device and method for detecting the permeability of a polar plate, and the device comprises a mold which is used for bearing and sealing a sample and is provided with an air inlet and an air outlet; the gas supply source is communicated with the gas inlet of the mold through a gas inlet pipeline and is used for providing gas for testing for the mold; the pressure regulating filter is arranged on the gas inlet pipeline and is used for regulating the gas pressure of the gas supply source and filtering the gas; the differential pressure gauge is used for detecting upper and lower end pressure difference of the sample; and the gas flow meter is arranged on a gas outlet pipeline communicated with the gas outlet and is used for detecting the flow of gas penetrating through the sample. The device quantitatively detects the permeability of the lead-acid storage battery pole plate based on the gas pressure difference, can also be used for detecting the permeability of other porous materials, and is wide in application range.

Description

Technical Field

[0001] The present invention relates to a permeability detection device, in particular to a test device and method for detecting the permeability of a plate electrode. Background Art

[0002] As a core component of a lead-acid battery, the permeability of the plate electrode is a key factor affecting the battery performance. The permeability of the plate electrode determines the ease of ion transport between the electrolyte and the active material, thereby affecting the charge and discharge efficiency, cycle life, and energy density of the battery. A higher permeability can promote the rapid migration of ions, improve the charge and discharge rate of the battery, reduce the internal resistance of the battery, and reduce energy loss.

[0003] Currently, the methods related to measuring the permeability of the plate electrode of a lead-acid battery are mainly the liquid adsorption method, and the proportion of pores in the plate electrode is calculated by the moisture absorbed by the plate electrode. For example, the invention patent application with the publication number CN 105241799A specifically discloses a plate electrode porosity detection device and detection method, including a controller, a memory, a display, a plastic sealed box body filled with an acidic solution, a liquid inlet, a buzzer sensor, a micro pump for adding the acidic solution into the box body, two wire holes for passing wires, and a turning plate arranged on the upper box plate of the box body; a sealing cover is arranged on the liquid inlet, a sealing structure is arranged on the turning plate, and an observation window is arranged on the upper box plate close to the two wire holes. This method requires the plate electrode to be soaked in the liquid for a long time, and the detection time is long, which affects the test efficiency. Summary of the Invention

[0004] Based on this, in view of the above technical problems existing in the prior art, it is necessary to provide a test device and method for detecting the permeability of a plate electrode, which quantitatively detects the permeability of the plate electrode of a lead-acid battery based on the gas pressure difference, and this device can also be used to detect the permeability of other porous materials, with a wide application range.

[0005] To solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A test device for detecting the permeability of a plate electrode, comprising:

[0007] A mold for carrying and sealing a sample, provided with an air inlet and an air outlet;

[0008] A gas supply source communicated with the air inlet of the mold through an air inlet pipeline for supplying test gas to the mold;

[0009] A pressure regulating filter arranged on the air inlet pipeline for regulating the gas pressure of the gas supply source and filtering the gas;

[0010] A differential pressure gauge for detecting the pressure difference between the upper and lower ends of the sample;

[0011] A gas flow meter is arranged on the gas outlet pipeline communicated with the gas outlet, and is used for detecting the gas flow rate passing through the sample.

[0012] Preferably, the mold includes an upper mold and a lower mold, and the upper mold and the lower mold together can form a closed chamber, and the sample is located in the closed chamber.

[0013] Preferably, the test device includes a bushing for carrying the sample. The bushing is located in the closed chamber and includes an upper bushing and a lower bushing. Both the upper bushing and the lower bushing are hollow structures, and the sample is placed between the upper bushing and the lower bushing.

[0014] Preferably, a first seal is arranged between the upper bushing and the lower bushing.

[0015] Preferably, a second seal is arranged between the bushing and the mold.

[0016] Preferably, the test device includes a pressurizing device for applying pressure to the mold to prevent air leakage of the mold.

[0017] Preferably, a pressure relief valve is arranged on the gas outlet pipeline for exhausting the excess gas in the pipeline after the detection is completed, and a ball valve for starting the test is arranged on the gas inlet pipeline.

[0018] Preferably, the test gas is selected from one of nitrogen, argon or carbon dioxide.

[0019] To solve the above technical problems, another technical solution adopted by the present invention is:

[0020] A method for detecting the permeability of a plate electrode, applying the test device as described above, includes the following steps:

[0021] (1) Check the airtightness of the test device;

[0022] (2) Detect the sample: Put the sample to be tested into the mold, use the pressurizing device to fasten the upper and lower molds, adjust the pressure regulating filter to 0.5 MPa - 2 MPa, open the ball valve for testing, and record the values of the gas flow meter and the differential pressure gauge;

[0023] (3) Calculate the permeability of the plate electrode: Substitute the measured values into formula (1) to calculate the permeability of the plate electrode;

[0024]

[0025] In the formula:

[0026] K - Permeability of the material;

[0027] μ — Gas viscosity;

[0028] Z - Compression factor of the gas;

[0029] Q—Gas flow rate;

[0030] L—Thickness of the test sample;

[0031] A—Effective area of the sample;

[0032] P1—Pressure at the inlet end of the sample;

[0033] P2—Pressure at the outlet end of the sample.

[0034] Preferably, the specific operation of checking the airtightness of the test device in step (1) is as follows: First, place an iron sheet with the same size as the sample to be tested in the mold, fasten the upper and lower molds using the pressurizing device, adjust the pressure regulating filter to 0.5 MPa - 2 MPa, open the ball valve for testing. If there is no value shown on the gas flow meter, then close the ball valve and observe the change in the value in the differential pressure gauge. If the value in the differential pressure gauge shows basically no change, it indicates that the test device is well-sealed.

[0035] Due to the adoption of the above technical solutions, the present invention has the following advantages compared with the prior art:

[0036] The present invention quantitatively detects the permeability of lead-acid battery plates based on gas pressure difference, and this device can also be used to detect the permeability of other porous materials, with a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic structural diagram of the test device of the present invention;

[0038] Figure 2 It is a cross-sectional view of the mold of the present invention;

[0039] Figure 3 It is a schematic diagram of the sample of the present invention;

[0040] Among them: 1. Mold; 11. Upper mold; 111. Second accommodating groove; 12. Lower mold; 121. Third accommodating groove; 13. Inlet; 14. Outlet; 2. Gas supply source; 3. Pressure regulating filter; 4. Differential pressure gauge; 5. Gas flow meter; 6. Bushing; 61. Upper bushing; 62. Lower bushing; 621. First accommodating groove; 7. First seal; 8. Pressurizing device; 9. Pressure relief valve; 10. Ball valve; 101. Sample. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0041] To make the above objects, features, and advantages of the present invention more apparent and understandable, the following provides a detailed description of the specific embodiments of the present invention in conjunction with the accompanying drawings. Many specific details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0042] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "left", "right", "upper", "lower", and similar expressions used herein are only for the purpose of illustration.

[0043] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of the described features. In the description of the present application, the meaning of "a plurality" is two or more, unless otherwise specifically defined. In the present application, " / " means "or".

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0045] Currently, the main method for measuring the permeability of lead-acid battery plates is the liquid adsorption method, and the proportion of pores in the plates is calculated by the moisture absorbed by the plates.

[0046] On this basis, the present invention provides a test device for detecting the permeability of plates, including:

[0047] A mold for carrying and sealing the sample, provided with an air inlet and an air outlet;

[0048] A gas supply source connected to the air inlet of the mold through an air inlet pipeline for supplying test gas to the mold;

[0049] A pressure regulating filter provided on the air inlet pipeline for regulating the gas pressure of the gas supply source and filtering the gas;

[0050] A differential pressure gauge for detecting the pressure difference between the upper and lower ends of a sample;

[0051] A gas flow meter is arranged on the gas outlet pipeline communicated with the gas outlet for detecting the gas flow rate passing through the sample.

[0052] The present invention quantitatively detects the permeability of lead-acid battery plates based on gas pressure difference, and this device can also be used to detect the permeability of other porous materials, with a wide range of applications.

[0053] The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0054] Embodiment 1

[0055] An experimental device for detecting the permeability of battery plates in this embodiment includes a mold 1, a gas supply source 2, a pressure regulating filter 3, a differential pressure gauge 4, and a gas flow meter 5.

[0056] The mold 1 is used to carry and seal the sample 101, and is provided with an air inlet 13 and an air outlet 14. Specifically, the mold 1 includes an upper mold 11 and a lower mold 12. Both the upper mold 11 and the lower mold 12 have a cavity, and when the upper mold 11 and the lower mold 12 are combined, they can form a closed chamber, and the sample 101 is located in the closed chamber.

[0057] To better place the sample 101, a bushing 6 for carrying the sample 101 can be loaded and unloaded inside the mold 1 of this experimental device. The bushing 6 is located in the closed chamber and includes an upper bushing 61 and a lower bushing 62. Both the upper bushing 61 and the lower bushing 62 are hollow structures, specifically, they can be annular structures, and the sample 101 is placed between the upper bushing 61 and the lower bushing 62.

[0058] Specifically, a first accommodation groove 621 is arranged along the circumferential direction of the inner wall of the lower bushing 62, and the sample 101 is located in the first accommodation groove 621. The lower bushing 62 plays a role in supporting the sample 101. A second accommodation groove 111 is arranged on the inner wall of the side of the upper mold 11 facing the lower mold 12, and the upper bushing 61 is located in the second accommodation groove 111, and their shapes and sizes are mutually adapted. A third accommodation groove 121 is arranged on the inner wall of the side of the lower mold 12 facing the upper mold 11, and the lower bushing 62 is located in the third accommodation groove 121, and their shapes and sizes are mutually adapted.

[0059] The gas supply source 2 is communicated with the air inlet 13 of the mold 1 through an air inlet pipeline for supplying test gas to the mold 1. The test gas is selected from one of nitrogen, argon or carbon dioxide. Considering economy, nitrogen with a purity of 99.99% is preferably used in this embodiment.

[0060] The pressure regulating filter 3 is arranged on the air inlet pipeline for regulating the gas pressure of the gas supply source 1 and filtering the gas.

[0061] The differential pressure gauge 4 is used to detect the pressure difference between the upper and lower ends of the sample 101. Specifically, the differential pressure gauge 4 is respectively connected to the inlet pipeline and the outlet pipeline.

[0062] The gas flowmeter 5 is arranged on the outlet pipeline communicating with the air outlet 14, and is used to detect the gas flow rate passing through the sample 101.

[0063] In this embodiment, a pressure relief valve 9 is arranged on the outlet pipeline, which is used to discharge the redundant gas in the pipeline after the detection is completed, and a ball valve 10 for starting the test is arranged on the inlet pipeline.

[0064] Embodiment 2

[0065] As Figures 1 to 3 shown, a test device for detecting the permeability of a plate electrode in this embodiment includes a mold 1, a gas supply source 2, a pressure regulating filter 3, a differential pressure gauge 4, and a gas flowmeter 5.

[0066] The mold 1 is used to carry and seal the sample 101, and is provided with an air inlet 13 and an air outlet 14. Specifically, the mold 1 includes an upper mold 11 and a lower mold 12. Both the upper mold 11 and the lower mold 12 have a cavity, and the upper mold 11 and the lower mold 12 together can form a closed chamber, and the sample 101 is located in the closed chamber.

[0067] In order to better place the sample 101, a bushing 6 for carrying the sample 101 can be loaded and unloaded inside the mold 1 of this test device. The bushing 6 is located in the closed chamber and includes an upper bushing 61 and a lower bushing 62. Both the upper bushing 61 and the lower bushing 62 are hollow structures, specifically, they can be annular structures, and the sample 101 is placed between the upper bushing 61 and the lower bushing 62.

[0068] Specifically, the lower bushing 62 is provided with a first accommodation groove 621 along the circumferential direction of the inner wall, and the sample 101 is located in the first accommodation groove 621, and the lower bushing 62 plays a role in supporting the sample 101. A second accommodation groove 111 is arranged on the inner wall of the side of the upper mold 11 facing the lower mold 12, and the upper bushing 61 is located in the second accommodation groove 111, and their shapes and sizes are mutually adapted. A third accommodation groove 121 is arranged on the inner wall of the side of the lower mold 12 facing the upper mold 11, and the lower bushing 62 is located in the third accommodation groove 121, and their shapes and sizes are mutually adapted.

[0069] The gas supply source 2 is communicated with the air inlet 13 of the mold 1 through an inlet pipeline, and is used to provide test gas for the mold 1. The test gas is selected from one of nitrogen, argon or carbon dioxide. Considering economy, nitrogen with a purity of 99.99% is preferably used in this embodiment.

[0070] The pressure regulating filter 3 is arranged on the inlet pipeline, and is used to regulate the gas pressure of the gas supply source 1 and filter the gas.

[0071] The differential pressure gauge 4 is used to detect the pressure difference between the upper and lower ends of the sample 101. Specifically, the differential pressure gauge 4 is respectively connected to the inlet pipeline and the outlet pipeline.

[0072] The gas flow meter 5 is arranged on the outlet pipeline communicated with the air outlet 14 and is used to detect the gas flow rate passing through the sample 101.

[0073] In this embodiment, a pressure relief valve 9 is arranged on the outlet pipeline to discharge the redundant gas in the pipeline after the detection is completed, and a ball valve 10 for starting the test is arranged on the inlet pipeline.

[0074] In order to achieve a better sealing effect, in this embodiment, a first sealing member 7 is arranged between the upper bushing 61 and the lower bushing 62. A second sealing member is arranged between the bushing 6 and the mold 1. Specifically, a second sealing member is arranged between the lower bushing 62 and the lower mold 12. Both the first sealing member 7 and the second sealing member are O-ring seals for sealing. A sealing member is also arranged between the sample 101 and the bushing 6. Specifically, a sealing member is arranged between the lower surface end of the sample 101 and the lower bushing 62, and a sealing member (which can also be the first sealing member 7) is arranged between the upper surface end of the sample 101 and the upper bushing 61.

[0075] In this embodiment, the test device further includes a pressurizing device 8 for applying pressure to the mold 1 to prevent the mold 1 from leaking air, which better ensures the sealing performance of the mold 1.

[0076] The present invention also provides a method for detecting the permeability of a plate electrode, which applies the test device as described above and includes the following steps:

[0077] (1) Check the airtightness of the test device: First, place an iron sheet with the same size as the sample 101 to be measured in the mold 1, use the pressurizing device 8 to fasten the upper mold 11 and the lower mold 12, adjust the pressure regulating filter 3 to 0.5 MPa - 2 MPa, open the ball valve 10 for testing. If there is no value on the gas flow meter 5, then close the ball valve 10 and observe the change in the value in the differential pressure gauge 4. If the value in the differential pressure gauge 4 basically does not change, it indicates that the test device has good sealing and the next test can be carried out.

[0078] (2) Detect the sample: Use the pressure relief valve 9 to exhaust all the gas in the pipeline, unload the pressure of the pressurizing device 8, remove the iron sheet used to check the airtightness of the test device, place the sample 101 to be measured in the mold 1, use the pressurizing device 8 to fasten the upper mold 11 and the lower mold 12, adjust the pressure regulating filter 3 to 0.5 MPa - 2 MPa, open the ball valve 10 for testing, and record the values of the gas flow meter 5 and the differential pressure gauge 4.

[0079] (3) Calculate the permeability of the plate electrode: Substitute the measured values into formula (1) to calculate the permeability of the plate electrode;

[0080]

[0081] In the formula:

[0082] K - Permeability of the material, unit: cm 2 ;

[0083] μ — Gas viscosity, unit: Pa·s. The viscosity of nitrogen at 25°C is 1.75×10 -5 Pa·s;

[0084] Z - Compressibility factor of the gas. For nitrogen within 1 MPa, this value ≈ 1;

[0085] Q - Gas flow rate, unit: cm 3 / s;

[0086] L - Thickness of the test sample, unit: cm;

[0087] A - Effective area of the sample, unit: cm 2 ;

[0088] P1 - Pressure at the inlet end of the sample, unit: Pa;

[0089] P2 - Pressure at the outlet end of the sample, unit: Pa.

[0090] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as falling within the scope described in this specification.

[0091] The above-described embodiments merely represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the appended claims.

Claims

1. A test device for detecting the permeability of a plate electrode, characterized in that, Comprising: A mold for carrying and sealing a sample, provided with an air inlet and an air outlet; A gas supply source communicated with the air inlet of the mold through an inlet pipeline for supplying test gas to the mold; A pressure regulating filter disposed on the inlet pipeline for regulating the gas pressure of the gas supply source and filtering the gas; A differential pressure gauge for detecting the pressure difference between the upper and lower ends of the sample; A gas flowmeter disposed on an outlet pipeline communicated with the air outlet for detecting the gas flow rate passing through the sample.

2. The test device for detecting the permeability of the electrode plate according to claim 1, characterized in that, The mold includes an upper mold and a lower mold, and the upper mold and the lower mold together can form a sealed chamber, and the sample is located in the sealed chamber.

3. The test device for detecting the permeability of the detection electrode plate according to claim 2, wherein The test device includes a bushing for carrying the sample. The bushing is located in the sealed chamber and includes an upper bushing and a lower bushing. Both the upper bushing and the lower bushing are hollow structures, and the sample is placed between the upper bushing and the lower bushing.

4. The test device for detecting the permeability of the detection electrode plate according to claim 3, characterized in that, A first seal is provided between the upper bushing and the lower bushing.

5. The test device for detecting the permeability of the detection electrode plate according to claim 3, characterized in that, A second seal is provided between the bushing and the mold.

6. The test device for detecting the permeability of the detection electrode plate according to claim 1, characterized in that, The test device includes a pressurizing device for applying pressure to the mold to prevent air leakage of the mold.

7. The test device for detecting the permeability of the electrode plate according to claim 1, wherein, A pressure relief valve is provided on the outlet pipeline for exhausting the excess gas in the pipeline after the detection is completed, and a ball valve for starting the test is provided on the inlet pipeline.

8. The test device for detecting the permeability of the electrode plate according to claim 1, characterized in that, The test gas is selected from one of nitrogen, argon or carbon dioxide.

9. A method for detecting the permeability of a plate electrode, which uses the test device according to any one of claims 1 to Comprising the following steps: (1) Check the airtightness of the test device; (2) Detect the sample: Place the sample to be tested in the mold, fasten the upper and lower molds by using the pressurizing device, adjust the pressure regulating filter to 0.5 MPa - 2 MPa, open the ball valve for testing, and record the values of the gas flowmeter and the differential pressure gauge; (3) Calculate the permeability of the plate: Substitute the measured values into formula (1) to calculate the permeability of the plate; In the formula: K - Permeability of the material; μ — Gas viscosity; Z - Compressibility factor of the gas; Q - Gas flow rate; L - Thickness of the test sample; A - Effective area of the sample; P1 - Pressure at the air inlet end of the sample; P2 - Pressure at the air outlet end of the sample.

10. The method for detecting the permeability of the detection electrode plate according to claim 9, characterized in that, The specific operation of the step (1) of checking the airtightness of the test device is as follows: First, place an iron sheet with the same size as the sample to be tested in the mold, fasten the upper and lower molds by using the pressurizing device, adjust the pressure regulating filter to 0.5 MPa - 2 MPa, open the ball valve for testing. If there is no value on the gas flowmeter, then close the ball valve and observe the change in the value in the differential pressure gauge. If the value in the differential pressure gauge basically does not change, it indicates that the test device is well sealed.

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