CN212872149U - Electrochemical corrosion resistance testing device for lead-based alloy - Google Patents

Abstract

The utility model discloses a lead-based alloy electrochemical corrosion resistance testing device, which comprises a tank body, a handle, an anode clamping groove for placing a comparison electrode and an electrode to be tested, a cathode clamping groove for placing an auxiliary electrode, an anode terminal, a cathode terminal, a stirring motor, a liquid level monitor, a reference electrode mounting hole, a reference electrode terminal, a stirring paddle, a clamping groove baffle, a flow hole and a water replenishing hole; through the cooperation of the reference electrode, the auxiliary electrode and the reference electrode, the electrochemical corrosion resistance of the lead-based alloy is tested by using a testing device. The utility model discloses a testing arrangement, test result reproducibility is good, test cycle is short, simple swift, can be used to quick evaluation to lead-based alloy and lead-based alloy processing technology.

Description

Electrochemical corrosion resistance testing device for lead-based alloy

Technical Field

The utility model belongs to the technical field of resistant electrochemical corrosion test, concretely relates to resistant electrochemical corrosion testing arrangement of lead-based alloy.

Background

The grid of the lead-acid storage battery is generally prepared from lead-based alloy. Because the main component of the positive active material of the lead-acid storage battery is lead dioxide and the main component of the grid is lead, the lead dioxide and the lead grid can generate oxidation-reduction reaction to produce lead oxide; meanwhile, because the battery is charged by generally adopting a constant-voltage current-limiting mode, the potential of a positive electrode can rise to more than 2.6V, and the electrochemical corrosion condition exists in the sulfuric acid electrolyte atmosphere, the corrosion of the grid is inevitable, the corrosion of the grid can be improved and slowed down by designing the lead-based alloy of the grid and the structure of the grid, and the service life of the battery can not be influenced by the corrosion problem of the grid in the whole service cycle of the storage battery. Therefore, there is a need for electrochemical corrosion resistance testing of lead-based alloys used to make grids.

The normal service life of the battery is more than 3 years, and the time of 150-300 days is also needed for the laboratory to carry out rapid cycle test, so the test period is too long by adopting a normal method, and the design development progress is influenced. The conventional common method for testing the electrochemical corrosion resistance of the lead-based alloy at present is to combine a positive grid and a negative grid into a battery unit, introduce constant direct current to carry out electrochemical corrosion on the grid for a period of time, and evaluate the corrosion resistance of the grid or the lead-based alloy by testing and calculating the weight loss condition. The following problems exist with testing according to this method: firstly, the manufacturing process parameters and the structure of the grid have certain influence on the corrosion resistance of the grid, the direct use of the grid to test the corrosion resistance of the lead-based alloy cannot eliminate the influence caused by the influence of manufacturing and the like, and the corrosion resistance of the lead-based alloy cannot be accurately evaluated; secondly, in the grid corrosion resistance test process, a large amount of water is electrolyzed due to the fact that the voltage is higher than the decomposition voltage of the water, the concentration of the electrolyte is uneven, the concentration of the electrolyte is gradually increased, and the influence factor influencing the test result to be unstable is obtained; thirdly, the corrosion resistance of the grid is tested by adopting a constant current charging method, the current density is calculated according to the area of the plate surface of the polar plate, the calculation is rough, the real current density of the grid interface cannot be reflected, and the calculation is also a factor influencing the instability of the test result.

Therefore, it is necessary to design and develop a new technical solution to solve the above problems.

SUMMERY OF THE UTILITY MODEL

The utility model adopts the following technical proposal: a lead-based alloy electrochemical corrosion resistance testing device comprises a tank body, a handle, an anode clamping groove for placing a comparison electrode and an electrode to be tested, a cathode clamping groove for placing an auxiliary electrode, an anode terminal, a cathode terminal, a stirring motor, a liquid level monitor, a reference electrode mounting hole, a reference electrode terminal, a stirring paddle, clamping groove baffles, flow holes and water replenishing holes, wherein the handle is installed on the outer side walls of the front side and the rear side of the tank body, the anode clamping groove and the cathode clamping groove are distributed at the front end and the rear end in the tank body in a relatively parallel manner, the anode clamping groove and the cathode clamping groove are both composed of a pair of clamping groove baffles, the distance between each pair of clamping groove baffles is the same, the clamping groove baffles are vertically inserted into the tank body, a plurality of flow holes are uniformly distributed on the clamping groove baffles, the anode terminal is fixedly, cathode terminal fixed mounting is at the border position at the cell body top of cathode draw-in groove homonymy, agitator motor installs the well position in cell body top, the agitator motor below is connected with the stirring rake, the stirring rake sets up inside the cell body, the agitator motor left side is provided with the moisturizing hole, the agitator motor right side is provided with the reference electrode mounting hole, the reference electrode mounting hole sets up between agitator motor and reference electrode terminal, liquid level monitor is installed to the one corner at cell body top.

Further, the groove body is the main body of the testing device, and is preferably made of transparent PC material with the thickness of 5 mm.

Further, the distance between each pair of the clamping groove baffles is preferably 3 mm.

Further, the diameter of the flow hole is 8 mm.

A test method of a lead-based alloy electrochemical corrosion resistance test device comprises the following specific test steps:

1) preparing an electrode to be tested, a contrast electrode and an auxiliary electrode; soaking the reference electrode in an aqueous sulfuric acid solution for at least 24 hours; preparing a testing device; preparing charging test equipment with a constant-voltage current-limiting function as auxiliary test equipment, wherein the charging test equipment comprises a positive electrode output line, a positive electrode voltage acquisition line, a negative electrode output line and a negative electrode voltage acquisition line; adding an electrolyte into the tank body to a position of 120mm of liquid level by taking a sulfuric acid aqueous solution as the electrolyte; weighing the electrode to be tested and the comparison electrode to be m1 and m2 respectively;

2) symmetrically inserting an electrode to be tested and a contrast electrode into an anode clamping groove, inserting a reference electrode into a reference electrode mounting hole, and inserting an auxiliary electrode into a cathode clamping groove; connecting an auxiliary electrode with a cathode binding post, respectively connecting an electrode to be tested and a reference electrode with an anode binding post, replenishing electrolyte into the tank body to a position 125mm away from the liquid level through a water replenishing hole, connecting a positive electrode output line and a positive electrode voltage collecting line of a charging test device with the anode binding post, connecting a negative electrode output line of the charging test device with the cathode binding post, connecting a negative electrode voltage collecting line of the charging test device with the reference electrode binding post, and connecting a water delivery hose with the water replenishing hole;

3) starting a stirring motor, setting the stirring speed to be 5 revolutions per minute, and stirring the electrolyte; setting the constant voltage of the charging test equipment to be 2.6V, and continuously carrying out a test for 72h under the constant voltage; continuously stirring in the test process, monitoring the electrolyte level in the tank body by a liquid level monitor, and slowly injecting pure water or distilled water from the water supplementing hole after the liquid level is reduced to ensure that the electrolyte level height is 125 +/-1 mm in the whole test process;

4) after the test is finished, taking out the electrode to be tested and the comparison electrode from the anode clamping groove, soaking the electrode to be tested and the comparison electrode in sugar-alkali water at 60 ℃ for 15min, removing oxides generated by surface electrochemical corrosion, washing the electrode to be tested and the comparison electrode with tap water till the surface is bright, and then carrying out vacuum drying at 110 ℃ for 30 min;

5) respectively cutting off the tabs of the electrode to be tested and the comparative electrode by using scissors, wherein the weights of the tabs are respectively m3 and m4, and the weights of the rest electrodes are respectively m5 and m 6;

calculating the weight loss:

W1=（m5-m3）/（m1-m3）*100；

W2=（m6-m4）/（m2-m4）*100；

△W=（W2-W1）/W2*100；

w1 is the weight loss percentage of the electrode to be tested;

w2 is the percent weight loss of the comparative electrode;

the delta W is the relative corrosion resistance strength of the electrode to be tested, when the value is a positive value, the corrosion resistance of the electrode to be tested is higher than that of the comparison electrode, and the higher the ratio is, the stronger the corrosion resistance is; when the value is negative, the corrosion resistance of the electrode to be tested is lower than that of the comparison electrode, and the lower the ratio is, the poorer the corrosion resistance is.

Further, in step 3), the testing method is carried out in a fume hood, and the testing device needs to be placed in a constant-temperature water bath at 25 +/-2 ℃.

Further, in the step 1),

the preparation method of the electrode to be tested comprises the following steps: melting the lead-based alloy to be tested, casting the lead-based alloy into a lead block with the thickness of 10mm, preparing the lead block into a lead plate with the thickness of 2.5mm and the surface roughness Ra of less than 3 mu m through multi-stage rolling, cutting the lead plate into pole pieces with the thickness of 60-120 mm, and reserving a tab with the width of 6mm and the length of 20mm on the upper part of each pole piece;

the preparation method of the comparative electrode comprises the following steps: selecting lead alloy which is tested to meet the alloy standard of the battery and meets the design requirement of corrosion resistance in the normal service life cycle of the battery through practical application, and adopting the same preparation method as the electrode to be tested;

the preparation method of the auxiliary electrode comprises the following steps: and selecting electrolytic lead with the lead content of 99.994%, and preparing the auxiliary electrode by adopting the same preparation method as the electrode to be tested.

Further, in the step 1), the sulfuric acid aqueous solution is prepared from analytically pure sulfuric acid and distilled water, and the sulfuric acid aqueous solution is 1.35 +/-0.01 g/ml; the reference electrode is preferably a cadmium electrode.

Further, in the step 2), pure water or distilled water with the conductivity less than 1 mu S/cm is introduced into the water delivery hose; and the connecting components used by the reference electrode, the auxiliary electrode, the electrode to be tested and the contrast electrode are the lugs of the reference electrode, the auxiliary electrode, the electrode to be tested and the contrast electrode.

Further, the mass ratio of glucose, caustic soda and water in the sugar-containing alkaline water is 1:5: 50.

The utility model has the advantages that: the auxiliary electrode in the utility model enables the circuit in the testing method to form a complete closed circuit; the reference electrode in the utility model is a standard electrode, has stable potential and is used for measuring the potential of the anode; the utility model discloses a testing arrangement and test method, test result reproducibility is good, test cycle is short, simple swift, can be used to the quick evaluation to lead-based alloy and lead-based alloy processing technology.

Drawings

Fig. 1 is a schematic structural diagram of the testing device of the present invention.

Fig. 2 is a perspective view of the testing device of the present invention.

Fig. 3 is the overall schematic diagram of the stirring paddle of the present invention.

Fig. 4 is an overall schematic view of the clamping groove baffle of the present invention.

Fig. 5 is an overall schematic diagram of the testing method of the present invention.

Fig. 6 is a schematic structural diagram of the electrode to be tested according to the present invention.

Wherein: 1. the device comprises a tank body, 2, a handle, 3, an anode clamping groove, 4, a cathode clamping groove, 5, an anode terminal, 6, a cathode terminal, 7, a stirring motor, 8, a liquid level monitor, 9, a reference electrode, 10, a reference electrode terminal, 11, a stirring paddle, 12, a clamping groove baffle, 13, a flow hole, 14, an auxiliary electrode, 15, a comparison electrode, 16, a test electrode, 17, a water replenishing hole, 18, a reference electrode mounting hole, 19, an electromagnetic valve, 20, an electromagnetic valve data line, 21, a control center, 22, a liquid level detector data line, 23, charging test equipment, 24, a charging test equipment data line, 25, a positive output line, 26, a negative output line, 27, a positive voltage collecting line, 28, a negative voltage collecting line, 29, a lug, 30, a water storage barrel, 31, a water delivery hose, 32 and a testing device.

Detailed Description

As shown in fig. 1-6, a lead-based alloy electrochemical corrosion resistance testing device comprises a tank body 1 as a testing device main body, a handle 2, an anode clamping groove 3 for placing a comparison electrode 15 and an electrode 16 to be tested, a cathode clamping groove 4 for placing an auxiliary electrode 14, an anode terminal 5, a cathode terminal 6, a stirring motor 7, a liquid level monitor 8, a reference electrode mounting hole 18, a reference electrode terminal 10, a stirring paddle 11, clamping groove baffles 12, a flow hole 13 and a water replenishing hole 17, wherein the tank body 1 is made of a transparent PC material with the thickness of 5mm, the handle 2 is installed on the outer side walls of the front side and the rear side of the tank body 1, the anode clamping groove 3 and the cathode clamping groove 4 are relatively and parallelly distributed at the front end and the rear end inside the tank body 1, the anode clamping groove 3 and the cathode clamping groove 4 are both composed of a pair of clamping groove baffles 12, the distance between each pair of clamping groove baffles 12, evenly distributed has a plurality of flow hole 13 on draw-in groove baffle 12, the diameter of flow hole 13 is 8mm, flow hole 13 is used for the mobile exchange of electrolyte, the border position at the 1 top of cell body of 3 homonymies in positive pole draw-in groove of positive pole terminal 5 fixed mounting, the border position at the 1 top of cell body of 4 homonymies in negative pole terminal 6 fixed mounting, agitator motor 7 installs the centre position in 1 top of cell body, agitator motor 7 below is connected with stirring rake 11, stirring rake 11 sets up inside cell body 1, agitator motor 7 left side is provided with moisturizing hole 17, agitator motor 7 right side is provided with reference electrode mounting hole 18, reference electrode mounting hole 18 sets up between agitator motor 7 and reference electrode terminal 10, liquid level monitor 8 is installed to the one corner at cell body 1 top.

A test method of a lead-based alloy electrochemical corrosion resistance test device comprises the following specific test steps:

1) preparing an electrode to be tested 16, a contrast electrode 15 and an auxiliary electrode 14;

preparation method of electrode to be tested 16: melting the lead-based alloy to be tested, casting the lead-based alloy into a lead block with the thickness of 10mm, preparing the lead block into a lead plate with the thickness of 2.5mm and the surface roughness Ra of less than 3 mu m through multi-stage rolling, cutting the lead plate into pole pieces with the thickness of 60-120 mm, and reserving a tab 29 with the width of 6mm and the length of 20mm on the upper part of each pole piece;

preparation method of comparative electrode 15: selecting a lead alloy which is tested to meet the alloy standard of the battery and meets the design requirement of corrosion resistance in the normal service life cycle of the battery through practical application, and adopting the same preparation method as the electrode 16 to be tested;

the preparation method of the auxiliary electrode 14 comprises the following steps: the auxiliary electrode 14 is prepared by selecting electrolytic lead with lead content of 99.994% and adopting the same preparation method as the electrode 16 to be tested, so that a circuit in the test method can form a complete closed circuit.

Selecting a cadmium electrode as a reference electrode 9, and soaking the reference electrode 9 in a sulfuric acid aqueous solution prepared from analytically pure sulfuric acid and distilled water, wherein the sulfuric acid aqueous solution is 1.35 +/-0.01 g/ml for at least 24 hours; the reference electrode 9 is a standard electrode, has stable potential and is used for measuring the potential of the positive electrode;

preparing a testing device;

preparing a charging test device 23 with a constant voltage current limiting function as an auxiliary test device, wherein the charging test device 23 comprises a positive electrode output line 25, a positive electrode voltage collecting line 27, a negative electrode output line 26 and a negative electrode voltage collecting line 28;

adding an electrolyte into the tank body 1 through the top of the tank body 1 or a water replenishing hole 17 to a position of 120mm of a liquid level by taking a sulfuric acid aqueous solution as the electrolyte;

weighing the electrode to be tested 16 and the comparative electrode 15 as m1 and m2 respectively;

2) symmetrically inserting an electrode 16 to be tested and a contrast electrode 15 into the anode clamping groove 3, inserting the reference electrode 9 into the reference electrode mounting hole 18, and inserting the auxiliary electrode 14 into the cathode clamping groove 4; connecting an auxiliary electrode 14 with a cathode binding post 6, and respectively connecting an electrode to be tested 16 and a contrast electrode 15 with an anode binding post 5; electrolyte is added into the tank body 1 through the water supplementing hole 17 to the position of 125mm of the liquid level; connecting a positive electrode output line 25 and a positive electrode voltage collecting line 27 of the charging test equipment 23 with the positive electrode binding post 5, connecting a negative electrode output line 26 of the charging test equipment 23 with the negative electrode binding post 6, connecting a negative electrode voltage collecting line 28 of the charging test equipment 23 with the reference electrode binding post 10, and connecting a water delivery hose 31 controlled by the electromagnetic valve 19 with the water replenishing hole 17; the connecting components used for the reference electrode 9, the auxiliary electrode 14, the electrode to be tested 16 and the comparison electrode 15 are the tabs 29 of the reference electrode, the auxiliary electrode and the comparison electrode;

3) placing the testing device 32 in a constant-temperature water bath at 25 +/-2 ℃, starting the stirring motor 7, setting the stirring speed to be 5 revolutions per minute, and stirring the electrolyte;

the control center 21 sends a test program to the charging test equipment 23 through the charging test equipment data line 24, and the running data of the charging test equipment 23 can be fed back to the control center 21 through the charging test equipment data line 24 and recorded and stored; the liquid level monitor 8 transmits information to the control center 21 through a liquid level monitor data line 22 by detecting the liquid level, and the control center 21 controls the on-off of the electromagnetic valve 19 through the feedback data and an electromagnetic valve data line 20, so that the replenishment or stop of the electrolyte, pure water or distilled water in the testing device 32 is controlled;

setting the constant voltage of 2.6V of the charging test equipment 23, and continuously carrying out a test for 72h at the voltage; continuously stirring in the test process, simultaneously monitoring the liquid level of the electrolyte in the tank body 1 through a liquid level monitor 8, slowly injecting pure water or distilled water with the conductivity less than 1 mu S/cm in a water storage barrel 30 from a water supplementing hole 17 after the liquid level is reduced, ensuring that the liquid level of the electrolyte in the whole test process is 125 +/-1 mm, and carrying out the whole test process in a ventilation cabinet because a large amount of oxygen, hydrogen and acid-containing water vapor are released in the test process;

4) after the test is finished, taking the electrode 16 to be tested and the comparison electrode 15 out of the anode clamping groove 3, soaking the electrode in sugar-alkali water at 60 ℃ for 15min, removing oxides such as lead dioxide, lead oxide and lead sulfate generated by surface electrochemical corrosion, washing the electrode clean by tap water until the surface is bright, and then carrying out vacuum drying at 110 ℃ for 30 min; wherein the mass ratio of glucose, caustic soda and water of the sugar-containing alkaline water at the temperature of 60 ℃ is 1:5: 50;

5) cutting off the tabs 29 of the electrode 16 to be tested and the comparative electrode 15 by using scissors, respectively weighing the tabs 29 as m3 and m4, and weighing the rest electrodes as m5 and m 6;

calculating the weight loss:

W1=m5-m3/m1-m3*100；

W2=m6-m4/m2-m4*100；

△W=W2-W1/W2*100；

w1 is the weight loss percentage of the electrode 16 to be tested;

w2 is the percent weight loss of comparative electrode 15;

the delta W is the relative corrosion resistance strength of the electrode 16 to be tested, when the value is a positive value, the corrosion resistance of the electrode 16 to be tested is higher than that of the comparison electrode 15, and the higher the ratio is, the stronger the corrosion resistance is; when the value is negative, it means that the corrosion resistance of the electrode 16 to be tested is lower than that of the comparative electrode 15, and the lower the ratio, the worse the corrosion resistance.

Preparing 5 samples of the alloy to be tested according to the preparation method of the utility model, and carrying out comparison test with the same comparison alloy; and preparing the alloy to be tested into a grid according to a conventional method, and testing the corrosion resistance by using a constant current method.

The test results are compared as follows:

the (%) of the conventional test method represents the percent weight loss measured according to the conventional method.

Because the same alloy parallel test, sample 1-5 are same material, and from the test result, the deviation value between 5 samples of the same method test compares, can see that, use the utility model provides a result deviation of testing arrangement and test method test is little, and stability is high.

Claims (4)

1. The electrochemical corrosion resistance testing device for the lead-based alloy comprises a tank body (1) and is characterized by further comprising a handle (2), an anode clamping groove (3) for placing a comparison electrode (15) and an electrode (16) to be tested, a cathode clamping groove (4) for placing an auxiliary electrode (14), an anode binding post (5), a cathode binding post (6), a stirring motor (7), a liquid level monitor (8), a reference electrode mounting hole (18), a reference electrode binding post (10), a stirring paddle (11), clamping groove baffles (12), a flow hole (13) and a water replenishing hole (17), wherein the handle (2) is arranged on the outer side walls of the front side and the rear side of the tank body (1), the anode clamping groove (3) and the cathode clamping groove (4) are distributed at the front end and the rear end of the inside of the tank body (1) in a relatively parallel manner, and the anode clamping groove (3) and the cathode clamping groove (4) are both formed by, the space between each pair of the clamping groove baffles (12) is the same, the clamping groove baffles (12) are vertically inserted into the tank body (1), a plurality of flow holes (13) are uniformly distributed on the clamping groove baffles (12), the anode binding post (5) is fixedly arranged at the edge position of the top of the tank body (1) at the same side of the anode clamping groove (3), the cathode binding post (6) is fixedly arranged at the edge position of the top of the tank body (1) at the same side of the cathode clamping groove (4), the stirring motor (7) is arranged at the middle position above the top of the tank body (1), the lower part of the stirring motor (7) is connected with a stirring paddle (11), the stirring paddle (11) is arranged inside the tank body (1), the left side of the stirring motor (7) is provided with a water supplementing hole (17), the right side of the stirring motor (7) is provided with a reference electrode mounting hole (18), the reference electrode mounting hole (18) is arranged between the stirring motor (7), and a liquid level monitor (8) is arranged at one corner of the top of the tank body (1).

2. The electrochemical corrosion resistance test device for the lead-based alloy as claimed in claim 1, wherein the tank body (1) is a main body of the test device and is made of a transparent PC material with a thickness of 5 mm.

3. The lead-based alloy electrochemical corrosion resistance testing device of claim 1, wherein the distance between each pair of said slot baffles (12) is 3 mm.

4. The lead-based alloy electrochemical corrosion resistance testing device according to claim 1, wherein the diameter of the flow hole (13) is 8 mm.

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