Device and method for detecting anti-permeation short-circuit performance of partition plate for lead-acid storage battery

Abstract

The invention discloses a device and a method for detecting the anti-permeation short-circuit performance of a partition plate for a lead-acid storage battery, the device comprises a reaction tank, a charger, a pressure regulator and a heating system, and a negative plate, a partition plate to be detected, a positive plate and a hard base plate are sequentially placed in the reaction tank from bottom to top; the method specifically comprises the following steps: (1) taking a separator to be detected, a negative plate, a positive plate and a cardboard base plate; (2) sequentially putting the negative plate, the to-be-detected partition plate, the positive plate and the hard base plate into a reaction tank, and applying pressure; (3) adding liquid; (4) starting a heating system; and (5) charging, and recording the change of voltage along with time. The method is simple, convenient and rapid to operate and free of sulfuric acid corrosion risk, lead sulfate crystals do not need to be generated and then dissolved and deposited in the partition plate, Pb < 2 + > generated by electrochemical reaction on the positive electrode lead plate is directly deposited in the process of migration to the negative electrode through the partition plate, permeation short circuit is gradually generated, the short circuit test time is shorter, and the effect is more obvious.

Description

Technical Field

[0001] The invention relates to the technical field of lead-acid batteries, and more particularly to a device and method for detecting the anti-penetration short-circuit performance of a separator for a lead-acid battery. Background Art

[0002] Lead-acid batteries have a positive electrode of lead dioxide, a negative electrode of sponge-like lead, an electrolyte of aqueous sulfuric acid, and a separator (diaphragm) made of microporous rubber separators, microporous plastic separators or other materials depending on the type of lead-acid battery. The battery shell is made of hard rubber, engineering plastics, fiberglass and other materials.

[0003] Among them, the separator is a component between the positive and negative plates of the lead-acid battery. It can prevent the positive and negative plates from short-circuiting and ensure ion conductivity. Its importance is no less than the plate itself, so the separator is also called the "third pole" of the battery by industry insiders. The performance requirements of the separator are not only the insulation of the material itself, loose and porous, low resistance, good chemical stability, etc., but also require the separator to have greater mechanical strength. With the increasing use of polyethylene (PE) separators in lead-acid batteries, and the increasingly severe operating conditions of lead-acid batteries such as deep discharge, the problem of separator penetration in batteries has gradually increased.

[0004] The mechanism of separator penetration is as follows: According to the common ion effect, the solubility of lead sulfate in sulfuric acid solution is inversely proportional to the concentration of sulfuric acid, that is, the lower the concentration of sulfuric acid solution, the greater the solubility of lead sulfate. When the battery is discharged, the electrolyte density is the lowest (the sulfate ion concentration is the lowest), which makes the solubility of lead sulfate reach the highest. When the battery is charged, the sulfuric acid density gradually increases, and the solubility of lead sulfate gradually decreases, so that some lead ions will be precipitated and converted into metallic lead on the surface of the negative electrode. After long-term repeated charge / discharge of the battery, there will be velvety lead particles around the negative plate. Precipitation and growth, gradually forming dendrites, it will penetrate the separator and contact the positive plate to form a short circuit. In addition, lead compounds such as lead sulfate in the electrolyte will also deposit in the pores of the separator, and the detached plate active substances will also deposit on the surface of the separator and penetrate into the pores. Once the deposited metal substances penetrate the separator, it will also cause the separator to penetrate and short-circuit.

[0005] Separator penetration short circuit is an important reason for lead-acid battery failure. As people's requirements for vehicle comfort are getting higher and higher, cars are equipped with more and more electrical equipment functions, which will increase the frequency of battery over-discharge, and thus cause more and more separator penetration. In the design of lead-acid battery products, it is an important measure to extend the battery cycle life to select separators with better anti-penetration short circuit performance.

[0006] Therefore, how to quickly and efficiently verify the performance of PE separators in resisting permeation short circuits is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0007] In view of this, the object of the present invention is to provide a device and method for detecting the anti-penetration short-circuit performance of a separator for a lead-acid battery, so as to solve the deficiencies in the prior art.

[0008] In order to achieve the above object, the present invention adopts the following technical solution:

[0009] A device for detecting the anti-permeation short-circuit performance of a separator for a lead-acid battery, comprising a reaction tank, a charger, a pressure regulator and a heating system;

[0010] Among them, the negative electrode plate, the separator to be tested, the positive electrode plate and the hard pad are placed in the reaction tank from bottom to top. The negative electrode plate is connected to the negative electrode of the charger through the negative terminal connecting line, and the positive electrode plate is connected to the positive electrode of the charger through the positive terminal connecting line;

[0011] The pressure regulator is arranged directly above the reaction tank;

[0012] The heating system is arranged directly below the reaction tank.

[0013] Furthermore, the above detection device also includes a temperature control device, and the temperature control device is arranged in the reaction tank.

[0014] Furthermore, the detection device also includes a liquid discharge port, which is arranged at the bottom of the reaction tank.

[0015] Furthermore, the negative electrode plate and the positive electrode plate of the above-mentioned detection device are both pure lead plates or green electrode plates.

[0016] A method for detecting the anti-permeation short-circuit performance of a separator for a lead-acid battery, using the above-mentioned detection device, specifically comprises the following steps:

[0017] (1) Take two pure lead plates or green plates of the same size and flat, as the negative plate and positive plate, respectively, as well as the separator to be tested and the cardboard backing plate;

[0018] (2) The negative electrode plate, the separator to be tested, the positive electrode plate and the hard backing plate are placed in the reaction tank in the order, and then pressure is applied to the hard backing plate from top to bottom through the pressure regulator;

[0019] (3) Add liquid into the reaction tank to completely immerse the positive electrode plate and to be higher than the upper surface of the positive electrode plate;

[0020] (4) Turn on the heating system to keep the liquid warm;

[0021] (5) Connect the negative plate to the negative pole of the charger through the negative terminal connecting wire, and connect the positive plate to the positive pole of the charger through the positive terminal connecting wire, then charge and record the change of voltage over time during the charging process.

[0022] Furthermore, in the above step (3), the liquid is pure water, tap water or a lead ion solution.

[0023] Furthermore, in the above step (4), the insulation temperature is 25-40°C.

[0024] Furthermore, in the above step (5), the charging current density is 1-10 mA / cm 2 .

[0025] It can be seen from the above technical solution that compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] 1. During the charging process of the present invention, electrochemical reaction occurs between the positive and negative electrodes, Pb-2e→Pb 2+ (anode), Pb 2+ +2e→Pb (cathode). Since the cation Pb 2+ Continuously migrate to the cathode through the pores of the separator, Pb 2+ When electrons are obtained on the surface of the negative plate, metal lead will be continuously generated, forming branch-like lead dendrites, which will continue to grow into the separator, and eventually penetrate the separator to connect with the positive electrode, causing a short circuit. When the voltage drops rapidly, it means that a separator penetration short circuit has occurred inside the battery. By comparing the difference in the anti-penetration short circuit performance of different separators with the length of this time period, the anti-penetration short circuit performance of the separator to be tested can be accurately reflected.

[0027] 2. The present invention eliminates the process of soaking the plate in sulfuric acid solution, is easy and quick to operate, has no risk of sulfuric acid corrosion, and does not need to generate lead sulfate crystals and then dissolve and deposit them in the separator. Instead, the Pb generated by electrochemical reaction on the positive lead plate is directly 2+ The deposition occurs during the migration from the separator to the negative electrode, and a penetration short circuit gradually occurs. The short circuit test time is shorter and the effect is more obvious, which is worthy of promotion and application in the lead-acid battery industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0029] Figure 1Schematic diagram of the structure of the detection device for the anti-permeation short-circuit performance of the separator for the lead-acid battery in Example 1;

[0030] Figure 2 Voltage changes during charging for different separators;

[0031] Figure 3 It is the penetration phenomenon of A partition;

[0032] Figure 4 This is the penetration phenomenon of partition B.

[0033] Among them, 1-reaction tank, 2-charger, 3-pressure regulator, 4-heating system, 5-negative plate, 6-test separator, 7-positive plate, 8-hard pad, 9-negative terminal connecting wire, 10-positive terminal connecting wire, 11-temperature control device, 12-drain port. DETAILED DESCRIPTION

[0034] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0035] In the description of the present invention, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0036] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0037] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like 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 an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0039] Example 1

[0040] A device for testing the anti-penetration short-circuit performance of separators for lead-acid batteries, such as Figure 1 As shown, it includes a reaction tank 1, a charger 2, a pressure regulator 3, a heating system 4, a temperature control device 11 and a drain port 12;

[0041] Among them, the reaction tank 1 is sequentially placed with a negative electrode plate 5, a separator 6 to be tested, a positive electrode plate 7 and a hard pad 8 from bottom to top, the negative electrode plate 5 is connected to the negative electrode of the charger 2 through a negative terminal connecting line 9, and the positive electrode plate 7 is connected to the positive electrode of the charger 2 through a positive terminal connecting line 10;

[0042] The pressure regulator 3 is arranged directly above the reaction tank 1;

[0043] The heating system 4 is arranged directly below the reaction tank 1;

[0044] The temperature control device 11 is arranged in the reaction tank 1;

[0045] The drain port 12 is arranged at the bottom of the reaction tank 1;

[0046] The negative plate 5 and the positive plate 7 are both pure lead plates with a size of 70 mm*100 mm*1.0 mm;

[0047] The material of the hard backing plate 8 is polypropylene (PP) and has a thickness of 10 mm.

[0048] Example 2

[0049] The method for testing the anti-permeation short-circuit performance of the separator for lead-acid batteries adopts the detection device of Example 1, and specifically comprises the following steps:

[0050] (1) Take two flat pure lead plates with a size of 70 mm*100 mm*1.0 mm, as the negative electrode plate 5 and the positive electrode plate 7, as well as the separator 6 to be tested and the cardboard backing plate 8;

[0051] (2) The negative electrode plate 5, the separator 6 to be tested, the positive electrode plate 7 and the PP hard pad 8 with a thickness of 10 mm are placed in the reaction tank 1 in this order, and then a pressure of 20 KPa is applied from top to bottom to the PP hard pad 8 through the pressure regulator 3;

[0052] (3) Add 200 g of pure water into the reaction tank 1, completely immersing the positive electrode plate 7 and exceeding the upper surface of the positive electrode plate 7;

[0053] (4) Turn on the heating system 4 and the temperature control device 11 to keep the pure water at 40° C.;

[0054] (5) Connect the negative electrode plate 5 to the negative electrode of the charger 2 through the negative terminal connecting wire 9, and connect the positive electrode plate 7 to the positive electrode of the charger 2 through the positive terminal connecting wire 10, then perform 0.2A constant current charging, set the end voltage to 1V, and record the voltage change over time during the charging process;

[0055] (6) After the test is completed, the drain port 12 is opened to discharge the pure water in the reaction tank 1.

[0056] Example 3

[0057] The method for testing the anti-permeation short-circuit performance of the separator for lead-acid batteries adopts the detection device of Example 1, and specifically comprises the following steps:

[0058] (1) Take two flat pure lead plates with a size of 70 mm*100 mm*1.0 mm, as the negative electrode plate 5 and the positive electrode plate 7, as well as the separator 6 to be tested and the cardboard backing plate 8;

[0059] (2) The negative electrode plate 5, the separator 6 to be tested, the positive electrode plate 7 and the PP hard pad 8 with a thickness of 10 mm are placed in the reaction tank 1 in this order, and then a pressure of 20 KPa is applied from top to bottom to the PP hard pad 8 through the pressure regulator 3;

[0060] (3) Add 200 g of tap water into the reaction tank 1 to completely submerge the positive electrode plate 7 and to be higher than the upper surface of the positive electrode plate 7;

[0061] (4) Turn on the heating system 4 and the temperature control device 11 to keep the tap water at 25°C;

[0062] (5) Connect the negative electrode plate 5 to the negative electrode of the charger 2 through the negative terminal connecting wire 9, and connect the positive electrode plate 7 to the positive electrode of the charger 2 through the positive terminal connecting wire 10, then perform 0.2A constant current charging, set the end voltage to 1V, and record the voltage change over time during the charging process;

[0063] (6) After the test is completed, the drain port 12 is opened to discharge the tap water in the reaction tank 1.

[0064] Example 4

[0065] The method for testing the anti-permeation short-circuit performance of the separator for lead-acid batteries adopts the detection device of Example 1, and specifically comprises the following steps:

[0066] (1) Take two flat pure lead plates with a size of 70 mm*100 mm*1.0 mm, as the negative electrode plate 5 and the positive electrode plate 7, as well as the separator 6 to be tested and the cardboard backing plate 8;

[0067] (2) The negative electrode plate 5, the separator 6 to be tested, the positive electrode plate 7 and the PP hard pad 8 with a thickness of 10 mm are placed in the reaction tank 1 in this order, and then a pressure of 20 KPa is applied from top to bottom to the PP hard pad 8 through the pressure regulator 3;

[0068] (3) Add 200 g of lead ion solution into the reaction tank 1, completely immersing the positive electrode plate 7 and exceeding the upper surface of the positive electrode plate 7;

[0069] (4) turning on the heating system 4 and the temperature control device 11 to keep the lead ion solution at 35° C.;

[0070] (5) Connect the negative electrode plate 5 to the negative electrode of the charger 2 through the negative terminal connecting wire 9, and connect the positive electrode plate 7 to the positive electrode of the charger 2 through the positive terminal connecting wire 10, then perform 0.2A constant current charging, set the end voltage to 1V, and record the voltage change over time during the charging process;

[0071] (6) After the detection is completed, the drain port 12 is opened to discharge the lead ion solution in the reaction tank 1.

[0072] Performance Testing

[0073] Take two types of separators A and B, and test their anti-permeation short-circuit performance according to the method of Example 2. The results are as follows: Figure 2-4 shown.

[0074] Depend on Figure 2-4 It can be seen that the charging time of the battery with separator B for a sudden drop in voltage is longer than that of the battery with separator A, and the penetration phenomenon is lighter, indicating that separator B has better anti-penetration short-circuit performance.

[0075] The above test description shows that the present invention eliminates the process of soaking the plate with sulfuric acid solution, is simple and quick to operate, has no risk of sulfuric acid corrosion, does not need to generate lead sulfate crystals and then dissolve and deposit in the separator, but directly generates Pb sulfate by electrochemical reaction on the positive lead plate. 2+ The deposition occurs during the migration from the separator to the negative electrode, and a penetration short circuit gradually occurs. The short circuit test time is shorter and the effect is more obvious, which is worthy of promotion and application in the lead-acid battery industry.

[0076] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms must be directed to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification.

[0077] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A device for detecting the anti-permeation short-circuit performance of a separator for a lead-acid battery, characterized in that: It includes a reaction tank, a charger, a pressure regulator and a heating system; The reaction tank is provided with a negative electrode plate, a separator to be tested, a positive electrode plate and a hard pad in order from bottom to top, the negative electrode plate is connected to the negative electrode of the charger through a negative terminal connecting line, and the positive electrode plate is connected to the positive electrode of the charger through a positive terminal connecting line; The pressure regulator is arranged directly above the reaction tank; The heating system is arranged directly below the reaction tank.

2. The device for detecting the anti-permeation short-circuit performance of a separator for a lead-acid battery according to claim 1, characterized in that: It also includes a temperature control device, which is arranged in the reaction tank.

3. The device for detecting the anti-permeation short-circuit performance of a separator for a lead-acid battery according to claim 1, characterized in that: It also includes a liquid discharge port, which is arranged at the bottom of the reaction tank.

4. The device for detecting the anti-permeation short-circuit performance of a separator for a lead-acid battery according to claim 1, characterized in that: The negative electrode plate and the positive electrode plate are both pure lead plates or green electrode plates.

5. A method for testing the anti-permeation short-circuit performance of a separator for a lead-acid battery, characterized in that: The detection device as claimed in claim 1 specifically comprises the following steps: (1) Take two pure lead plates or green plates of the same size and flat, as the negative plate and positive plate, respectively, as well as the separator to be tested and the cardboard backing plate; (2) The negative electrode plate, the separator to be tested, the positive electrode plate and the hard backing plate are placed in the reaction tank in the order, and then pressure is applied to the hard backing plate from top to bottom through the pressure regulator; (3) Add liquid into the reaction tank to completely immerse the positive electrode plate and to be higher than the upper surface of the positive electrode plate; (4) Turn on the heating system to keep the liquid warm; (5) Connect the negative plate to the negative pole of the charger through the negative terminal connecting wire, and connect the positive plate to the positive pole of the charger through the positive terminal connecting wire, then charge and record the change of voltage over time during the charging process.

6. The method for detecting the anti-permeation short-circuit performance of a separator for a lead-acid battery according to claim 5, characterized in that: In step (3), the liquid is pure water, tap water or a lead ion solution.

7. The method for detecting the anti-permeation short-circuit performance of a separator for a lead-acid battery according to claim 5, characterized in that: In step (4), the insulation temperature is 25-40°C.

8. The method for detecting the anti-permeation short-circuit performance of a separator for a lead-acid battery according to claim 5, characterized in that: In step (5), the charging current density is 1-10 mA / cm 2 .

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