Test method for water resistance and short-circuit performance of lead alloy grid on positive plate of battery

Abstract

This invention discloses a test method for the resistance of lead-grid alloy in the positive electrode plate of a storage battery to hydration short circuits, specifically implemented according to the following steps: Step 1, preparing an electrolyte for electrochemical scanning; Step 2, fabricating a working electrode; Step 3, using a three-electrode system on an electrochemical workstation, performing linear sweep voltammetry (LSV) on the working electrode to determine the peak potential and current density of the oxidation peak appearing in the potential range of -0.4V to 0.4V. This invention aims to solve the problem of hydration short circuits in storage batteries existing in the prior art.

Description

Technical Field

[0001] This invention belongs to the field of lead-acid battery technology, specifically relating to a test method for the water resistance and short-circuit performance of the positive plate grid lead alloy of a battery. Background Technology

[0002] During the use of lead-acid batteries, if they are continuously discharged by low-power electrical appliances or due to the static power consumption of these appliances, the stored electrical energy in the battery may be completely released. Upon recharging, a short circuit may be found inside the battery, causing it to malfunction. Experimental analysis suggests that this phenomenon is caused by conductive lead oxide, produced by the oxidation of the positive plate grid lead alloy, penetrating the gaps in the separator and connecting the positive and negative plates. Since there are currently no reports of this phenomenon in relevant literature, it is tentatively termed a hydration short circuit. This hydration short circuit causes an internal short circuit in the battery, leading to premature battery failure and significant waste. Summary of the Invention

[0003] The purpose of this invention is to provide a test method for the resistance of the positive plate grid lead alloy of a battery to hydration short circuit, so as to solve the problem that hydration short circuits are prone to occur in existing technologies.

[0004] The technical solution adopted in this invention is a test method for the water resistance and short-circuit performance of the positive plate grid lead alloy of a storage battery, which is implemented according to the following steps:

[0005] Step 1: Prepare the electrolyte for electrochemical scanning;

[0006] Step 2: Fabricate the working electrode;

[0007] Step 3: On an electrochemical workstation, using a three-electrode system, perform linear sweep voltammetry (LSV) on the working electrode to determine the peak potential and current density of the oxidation peak that appears in the potential range of -0.4V to 0.4V.

[0008] The invention is further characterized in that,

[0009] Step 1 is implemented in the following steps:

[0010] First, dissolve the corresponding mass of water-soluble non-variable valence metal sulfate in pure water, controlling the SO4 content. 2-The concentration of the solution is 0.001M to 0.006M, and 10ml to 25ml of 5M H2SO4 is added. After mixing, pure water is added to make the volume of the water-soluble non-variable valence metal sulfate solution reach 1.0L. A certain amount of the prepared water-soluble non-variable valence metal sulfate solution is taken again, heated to a gentle boil, and alkaline lead compounds with a particle size of less than 0.1mm are slowly added while stirring. The pH value of the water-soluble non-variable valence metal sulfate solution is adjusted to 7.5 to 9.5. The solution is cooled to room temperature and allowed to stand for 10h to 24h. Finally, the solution is filtered and the filtrate is collected. The collected filtrate is the electrolyte for electrochemical scanning. The electrolyte for electrochemical scanning is sealed and stored for no more than one week.

[0011] In step 1, the water-soluble non-variable valence metal sulfate is one or a mixture of several of the following: Li2SO4, Na2SO4, K2SO4, MgSO4, ZnSO4, or Al2(SO4)3.

[0012] The alkaline lead compound in step 1 is one or a mixture of several of the following: PbO, Pb(OH)2, PbO·PbSO4, 3PbO·PbSO4, 4PbO·PbSO4, or lead powder manufactured in the battery production process.

[0013] Step 2 is implemented in the following steps:

[0014] The lead-plated positive electrode plate to be tested is machined into a cylinder with a diameter of 10mm to 15mm. A wire is welded to one end of the cylindrical lead-plated positive electrode plate to be tested. The exposed metal on the side of the cylindrical lead-plated positive electrode plate to be tested and the welded wire end are sealed with epoxy resin. After the epoxy resin cures, the other end of the cylindrical lead-plated positive electrode plate to be tested is ground so that the area of ​​the exposed working surface is less than 0.8cm². 2 ~1.7cm 2 Then polish it with 800-1800 grit wet sandpaper until it is shiny to obtain the working electrode.

[0015] Step 3 is as follows:

[0016] At a temperature of 15℃~30℃, a linear scan LSV test was performed on the working electrode obtained in step 2 using a three-electrode system on an electrochemical workstation. The auxiliary electrode was a pure lead electrode with an area not less than 4 times that of the working electrode. The reference electrode was an Hg / Hg2SO4 / saturated K2SO4 electrode. The electrolyte solution was the electrochemical scanning electrolyte prepared in step 1.

[0017] Step 3 is implemented in the following steps:

[0018] Step 3.1: First, polarize the working electrode at -1.2V for 10 min to 30 min, then scan from -1.2V to 1.2V at a scanning speed of 0.001V / s to 0.005V / s to obtain the linear scanning current density versus potential curve of the working electrode.

[0019] Step 3.2: Analyze the linear scan current density versus potential graph of the working electrode to determine the peak potential and current density of the oxidation peak that appears in the potential range of -0.4V to 0.4V;

[0020] Step 3.3: By comparing the peak current densities of different positive plate grid lead alloy working electrodes, determine the relative performance of different positive plate grid lead alloys in resisting hydration and short circuits. Positive plate grid lead alloys with higher peak current densities exhibit worse resistance to hydration and short circuits; conversely, positive plate grid lead alloys with lower peak current densities exhibit better resistance to hydration and short circuits.

[0021] The beneficial effects of this invention are that the test method for the water resistance short-circuit performance of the lead alloy grid of the positive plate of a storage battery is simple, easy to implement, and reliable. It is applicable to the entire process of storage battery technology research, product development, manufacturing, and quality control. Attached Figure Description

[0022] Figure 1 This is a comparison of the linear scanning current density versus potential for two types of positive electrode grid lead alloys, A and B, in the test method for the water resistance and short-circuit performance of the positive electrode grid lead alloy of the present invention. Detailed Implementation

[0023] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0024] The present invention relates to a test method for the water resistance and short-circuit performance of the positive plate grid lead alloy of a storage battery, which is implemented according to the following steps:

[0025] Step 1: Prepare the electrolyte for electrochemical scanning;

[0026] Step 1 is implemented in the following steps:

[0027] First, dissolve the corresponding mass of water-soluble non-variable valence metal sulfate in pure water, controlling the SO4 content. 2-The concentration of the solution is 0.001M to 0.006M, and 10ml to 25ml of 5M H2SO4 is added. After mixing, pure water is added to make the volume of the water-soluble non-variable valence metal sulfate solution reach 1.0L. A certain amount of the prepared water-soluble non-variable valence metal sulfate solution is taken again, heated to a gentle boil, and alkaline lead compounds with a particle size of less than 0.1mm are slowly added while stirring. The pH value of the water-soluble non-variable valence metal sulfate solution is adjusted to 7.5 to 9.5. The solution is cooled to room temperature and allowed to stand for 10h to 24h. Finally, the solution is filtered and the filtrate is collected. The collected filtrate is the electrolyte for electrochemical scanning. The electrolyte for electrochemical scanning is sealed and stored for no more than one week.

[0028] In step 1, the water-soluble non-variable valence metal sulfate is one or a mixture of several of the following: Li2SO4, Na2SO4, K2SO4, MgSO4, ZnSO4, or Al2(SO4)3.

[0029] The alkaline lead compound in step 1 is one or a mixture of several of the following: PbO, Pb(OH)2, PbO·PbSO4, 3PbO·PbSO4, 4PbO·PbSO4, or lead powder manufactured in the battery production process.

[0030] Step 2: Fabricate the working electrode;

[0031] Step 2 is implemented in the following steps:

[0032] The lead-plated positive electrode plate to be tested is machined into a cylinder with a diameter of 10mm to 15mm. A wire is welded to one end of the cylindrical lead-plated positive electrode plate to be tested. The exposed metal on the side of the cylindrical lead-plated positive electrode plate to be tested and the welded wire end are sealed with epoxy resin. After the epoxy resin cures, the other end of the cylindrical lead-plated positive electrode plate to be tested is ground so that the area of ​​the exposed working surface is less than 0.8cm². 2 ~1.7cm 2 Then polish it with 800-1800 grit wet sandpaper until it is shiny to obtain the working electrode.

[0033] Step 3: On an electrochemical workstation, using a three-electrode system, perform linear sweep voltammetry (LSV) on the working electrode to determine the peak potential and current density of the oxidation peak that appears in the potential range of -0.4V to 0.4V.

[0034] Step 3 is as follows:

[0035] At a temperature of 15℃~30℃, a linear scan LSV test was performed on the working electrode obtained in step 2 using a three-electrode system on an electrochemical workstation. The auxiliary electrode was a pure lead electrode with an area not less than 4 times that of the working electrode. The reference electrode was an Hg / Hg2SO4 / saturated K2SO4 electrode. The electrolyte solution was the electrochemical scanning electrolyte prepared in step 1.

[0036] Step 3 is implemented in the following steps:

[0037] Step 3.1: First, polarize the working electrode at -1.2V for 10 min to 30 min, then scan from -1.2V to 1.2V at a scanning speed of 0.001V / s to 0.005V / s to obtain the linear scanning current density versus potential curve of the working electrode.

[0038] Step 3.2: Analyze the linear scan current density versus potential graph of the working electrode to determine the peak potential and current density of the oxidation peak that appears in the potential range of -0.4V to 0.4V;

[0039] Step 3.3: By comparing the peak current densities of different positive plate grid lead alloy working electrodes, determine the relative performance of different positive plate grid lead alloys in resisting hydration and short circuits. Positive plate grid lead alloys with higher peak current densities exhibit worse resistance to hydration and short circuits; conversely, positive plate grid lead alloys with lower peak current densities exhibit better resistance to hydration and short circuits.

[0040] Example

[0041] The present invention was used to test the water resistance and short-circuit performance of the positive plate grid lead alloy of two types of batteries, A and B, as follows:

[0042] Step 1: Prepare the electrolyte for electrochemical scanning. First, dissolve 0.006 mol of Na₂SO₄ in pure water, and add 20 ml of 5M H₂SO₄ aqueous solution. Add pure water to make the volume reach 1.0 L. Take 200 ml of the prepared Na₂SO₄ solution, heat to a gentle boil, and slowly add lead powder (manufactured during the battery manufacturing process) with a particle size of less than 5 μm while stirring, until the pH value reaches 8-9. Cool to room temperature and let stand for 15 hours. Finally, filter and collect the filtrate. The electrolyte for electrochemical scanning should be stored in a sealed container and should not be stored for more than one week.

[0043] Step 2: Machin the lead alloy to be tested into cylinders with a diameter of 11.3 mm. Weld a lead wire to one end of each cylinder. Seal the exposed metal on the sides of the cylinder and the end of the welded wire with epoxy resin. After the epoxy resin has cured, grind the other end of the cylinder so that the exposed working surface area is 1.0 cm². 2 Then polish it with 1500-grit wet sandpaper until it is shiny; this electrode is the working electrode.

[0044] Step 3: At room temperature (15°C), the working electrode was tested using a linear sweep voltammetry method with a three-electrode system on an electrochemical workstation. The auxiliary electrode was a pure lead electrode with an electrode area of ​​5 cm². 2 The reference electrode was a Hg / Hg2SO4 / saturated K2SO4 electrode; the electrolyte solution was the prepared electrochemical scanning electrolyte.

[0045] During the test, the working electrode was first polarized at -1.2V for 10 minutes, and then scanned from -1.2V to 1.2V at a scanning speed of 0.005V / s to obtain the linear scanning current density of the working electrode as a function of potential. Furthermore, a comparison graph of the linear scanning current density as a function of potential was obtained.

[0046] An analysis was performed on the linear scan current density versus potential variation graphs for working electrodes A and B. Figure 1 As shown, within the potential range of -0.4V to 0.4V, the oxidation peak potential of lead alloy A is 0.066V, and the peak current density is 2.284 mA·cm⁻¹. -2 The oxidation peak potential of lead alloy B is -0.246V, and the peak current is 0.379 mA·cm⁻¹. -2 ).

[0047] Since the peak current density of lead alloy A is much greater than that of lead alloy B, the short-circuit resistance of lead alloy B to water erosion is superior to that of lead alloy A.

Claims

1. A test method for the water resistance and short-circuit performance of the lead alloy grid of the positive plate of a storage battery, characterized in that, The specific steps are as follows: Step 1: Prepare the electrolyte for electrochemical scanning; Step 2: Fabricate the working electrode; Step 3: On an electrochemical workstation, using a three-electrode system, perform linear sweep voltammetry (LSV) on the working electrode to determine the peak potential and current density of the oxidation peak that appears in the potential range of -0.4V to 0.4V. Step 3 is as follows: At a temperature of 15℃~30℃, a linear scan LSV test was performed on the working electrode obtained in step 2 using a three-electrode system on an electrochemical workstation. The auxiliary electrode was a pure lead electrode with an area not less than 4 times that of the working electrode. The reference electrode was an Hg / Hg2SO4 / saturated K2SO4 electrode. The electrolyte solution was the electrochemical scanning electrolyte prepared in step 1. Step 3 is implemented in the following steps: Step 3.1: First, polarize the working electrode at -1.2V for 10 min to 30 min, then scan from -1.2V to 1.2V at a scanning speed of 0.001V / s to 0.005V / s to obtain the linear scanning current density of the working electrode as a function of potential. Step 3.2: Analyze the linear scan current density versus potential graph of the working electrode to determine the peak potential and current density of the oxidation peak that appears in the potential range of -0.4V to 0.4V; Step 3.3: By comparing the peak current densities of different positive plate grid lead alloy working electrodes, determine the superiority or inferiority of the water erosion short-circuit performance of different positive plate grid lead alloys; the higher the peak current density of the positive plate grid lead alloy, the worse the water erosion short-circuit performance; the lower the peak current density of the positive plate grid lead alloy, the better the water erosion short-circuit performance.

2. The test method for the water resistance and short-circuit performance of the lead alloy grid of the positive electrode plate of a storage battery according to claim 1, characterized in that, Step 1 is implemented in the following steps: First, dissolve the corresponding mass of water-soluble non-variable valence metal sulfate in pure water, controlling the SO4 content. 2- The concentration of the solution is 0.001M to 0.006M, and 10ml to 25ml of 5M H2SO4 is added. After mixing, pure water is added to make the volume of the water-soluble non-variable valence metal sulfate solution reach 1.0L. A certain amount of the prepared water-soluble non-variable valence metal sulfate solution is taken again, heated to a gentle boil, and alkaline lead compounds with a particle size of less than 0.1mm are slowly added while stirring. The pH value of the water-soluble non-variable valence metal sulfate solution is adjusted to 7.5 to 9.

5. The solution is cooled to room temperature and allowed to stand for 10h to 24h. Finally, the solution is filtered and the filtrate is collected. The collected filtrate is the electrolyte for electrochemical scanning. The electrolyte for electrochemical scanning is sealed and stored for no more than one week.

3. The test method for the water resistance and short-circuit performance of the lead alloy grid of the positive plate of a storage battery according to claim 2, characterized in that, In step 1, the water-soluble non-variable valence metal sulfate is one or a mixture of several of Li2SO4, Na2SO4, K2SO4, MgSO4, ZnSO4 or Al2(SO4)3.

4. The test method for the water resistance and short-circuit performance of the lead alloy grid of the positive plate of a storage battery according to claim 2, characterized in that, The alkaline lead compound in step 1 is one or a mixture of several of the following: PbO, Pb(OH)2, PbO•PbSO4, 3PbO•PbSO4, 4PbO•PbSO4, or lead powder manufactured in the battery production process.

5. The test method for the water resistance and short-circuit performance of the lead alloy grid of the positive plate of a storage battery according to claim 2, characterized in that, Step 2 is implemented in the following steps: The lead-plated positive electrode plate to be tested is machined into a cylinder with a diameter of 10mm to 15mm. A wire is welded to one end of the cylindrical lead-plated positive electrode plate to be tested. The exposed metal on the side of the cylindrical lead-plated positive electrode plate to be tested and the welded wire end are sealed with epoxy resin. After the epoxy resin cures, the other end of the cylindrical lead-plated positive electrode plate to be tested is ground so that the area of ​​the exposed working surface is less than 0.8cm². 2 ~1.7cm 2 Then polish it with 800-1800 grit wet sandpaper until it is shiny to obtain the working electrode.

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