Lead storage battery pole plate and manufacturing method thereof

Abstract

The invention discloses a lead storage battery pole plate and a manufacturing method thereof. The polar plate is produced by a continuous casting and continuous coating method and is not coated with a plate coating film, and the coated polar plate is cooled by spraying liquid nitrogen, so that the polar plate is rapidly cooled to-6 DEG C to-3 DEG C. The surface layer of the smeared wet green plate is rapidly cooled, and the problem that the continuous casting and continuous coating green plate is stained with paste is solved; the polar plate lead plaster water content is locked, the polar plate porosity is improved, and the polar plate performance is improved; the battery formation is thorough, and the initial capacity of the battery is improved.

Description

Technical Field

[0001] This invention belongs to the field of lead-acid battery production technology, specifically relating to a lead-acid battery electrode plate and its manufacturing method. Background Technology

[0002] Early battery production used cast grids. Large grids were coated, acid-leached, surface-dried, and cured before being slit into small green plates. Because of the acid-leaching process, there was no need to coat the plate surface with a film. For example, invention application CN108630902A discloses a lead-acid battery plate manufacturing process in which lead paste is applied to the grid and then acid-leached by an acid-leaching roller.

[0003] Subsequently, due to environmental issues (the generation of waste acid from acid leaching), some companies canceled this process. However, the plates cracked severely after surface drying, affecting battery performance.

[0004] Electrode plates manufactured using the mesh forming process tend to stick together when stacked because the lead paste surface is not acid-leached. To improve this problem, a plate film must be coated on the electrode plate surface.

[0005] For example, the invention application with publication number CN112768641A discloses a method for preparing lead-acid battery plates and lead-acid battery plates, wherein the plates obtained after coating are subjected to acid leaching or paper coating.

[0006] Since mesh plates are generally used in flooded batteries, the coating film is prone to self-dissolution due to the strong impact of side reaction gases during formation, which has little impact on battery capacity.

[0007] Continuously cast and coated plates are used in valve-regulated batteries. Due to the support and wrapping effect of the glass fiber separator, the coating film is not easily dissolved during formation, resulting in insufficient battery discharge capacity. Summary of the Invention

[0008] This invention improves battery discharge performance by not covering the coated continuous casting plate with a coating film, rapidly cooling the surface of the lead paste by spraying liquid nitrogen, causing the surface lead paste to slightly harden, facilitating subsequent processes, and then manufacturing green electrode plates through curing and drying.

[0009] This invention first provides a method for manufacturing lead-acid battery plates. The plates are produced by continuous casting and coating without a coating film. The coated plates are cooled by spraying liquid nitrogen to rapidly cool them to -6 to -3°C.

[0010] If the temperature is too high after liquid nitrogen cooling, the surface of the electrode will not harden, and there is a risk that the electrode will stick together when it is stacked on the curing rack. If the temperature is too low, the hardened layer on the electrode surface will be thick, and there will be more powder floating after the surface layer is cured and dried.

[0011] Preferably, the liquid nitrogen cooling time is 1.0 to 1.5 seconds.

[0012] Preferably, the smearing speed is controlled at 12~18 meters / minute.

[0013] Preferably, when using liquid nitrogen for cooling, the nozzle spray rate is 60~100L / h.

[0014] More preferably, when using liquid nitrogen for cooling, the vertical distance between the nozzle and the electrode surface is 5-8 cm.

[0015] Preferably, the temperature of the electrode plate is detected after cooling with liquid nitrogen. If the electrode plate temperature is higher than -3°C, the coating speed is reduced; if the electrode plate temperature is lower than -6°C, the coating speed is increased.

[0016] Preferably, after the electrode plates produced by continuous casting and coating are cooled by spraying liquid nitrogen, they are cut into single electrode plates. The single electrode plates are stacked on a curing rack and then placed in a curing chamber for curing and drying to complete the electrode plate manufacturing.

[0017] Preferably, the electrode plate is a positive electrode plate or a negative electrode plate.

[0018] The present invention further provides an electrode plate prepared by the aforementioned lead-acid battery electrode plate manufacturing method.

[0019] Beneficial effects of this invention: (1) Rapid surface cooling of the wet green plate after coating to solve the problem of paste adhesion on the green plate in continuous casting and coating; (2) Lock the moisture content of the lead paste on the electrode plate, increase the porosity of the electrode plate, and improve the performance of the electrode plate; (3) The plates are not coated, the battery is fully formed, and the initial capacity of the battery is improved. Attached Figure Description

[0020] Figure 1 The curves show the comparison of the third discharge capacity of batteries in Example 1 and Comparative Example 1.

[0021] Figure 2 The figures show the capacity discharge curves of the batteries in Example 2 and Comparative Example 2 after three discharge cycles.

[0022] Figure 3 The figures show the capacity discharge curves of batteries in Example 3 and Comparative Example 3 over three cycles. Detailed Implementation

[0023] Example 1 After applying lead paste to the 6-DZF-20 continuous casting and coating positive strip at a speed of 15 m / min, it enters a semi-sealed liquid nitrogen spraying treatment box for double-sided liquid nitrogen spraying treatment. The single nozzle spraying speed is set to 80 L / h, the vertical distance between the nozzle and the electrode surface is set to 6.5 cm, and the actual cooling time of the electrode liquid nitrogen spraying is 1.25 s. It is checked that the electrode is cooled by the liquid nitrogen surface layer. After exiting the liquid nitrogen spraying treatment box, the surface temperature of the electrode is checked to be -4℃.

[0024] The electrode plates from the liquid nitrogen treatment chamber are cut into small pieces and stacked directly on the curing rack. The electrode plates are then placed in the curing chamber for curing and drying to complete the manufacturing of the positive electrode plates.

[0025] After applying lead paste to the 6-DZF-20 continuous casting and coating negative plate strip at a speed of 17 m / min, it enters a semi-sealed liquid nitrogen spraying treatment chamber for double-sided liquid nitrogen spraying treatment. The single nozzle spraying speed is set to 80 L / h, the vertical distance between the nozzle and the plate surface is set to 6.5 cm, and the actual cooling time of the liquid nitrogen spraying on the plate is 1.25 s. It is checked that the plate is cooled by the liquid nitrogen surface layer. After exiting the liquid nitrogen spraying treatment chamber, the plate surface temperature is checked to be -5℃.

[0026] The electrode plates from the liquid nitrogen treatment chamber are cut into small pieces and stacked directly on the curing rack. The electrode plates are then placed in the curing chamber for curing and drying to complete the manufacturing of the negative electrode plates.

[0027] The positive and negative plates obtained above are assembled, acid is added, and the battery is charged to produce a 6-DZF-20 battery.

[0028] Example 2 After applying lead paste to the 6-DZF-21 continuous casting and coating strip at a speed of 12 m / min, it enters a semi-sealed liquid nitrogen spraying treatment chamber for double-sided liquid nitrogen spraying treatment. The single nozzle spraying speed is set to 60 L / h, the vertical distance between the nozzle and the electrode surface is set to 8 cm, and the actual cooling time of the liquid nitrogen spraying on the electrode is 1 second. It is checked that the electrode surface is cooled by the liquid nitrogen layer. After exiting the liquid nitrogen spraying treatment chamber, the surface temperature of the electrode is checked to be -3℃.

[0029] The electrode plates from the liquid nitrogen treatment chamber are cut into small pieces and stacked directly on the curing rack. The electrode plates are then placed in the curing chamber for curing and drying to complete the manufacturing of the positive electrode plates.

[0030] After applying lead paste to the 6-DZF-21 continuous casting and coating negative plate strip at a speed of 12 m / min, it enters a semi-sealed liquid nitrogen spraying treatment chamber for double-sided liquid nitrogen spraying treatment. The single nozzle spraying speed is set to 60 L / h, the vertical distance between the nozzle and the plate surface is set to 7 cm, and the actual cooling time of the liquid nitrogen spraying on the plate is 1.5 s. It is checked that the plate surface is cooled by the liquid nitrogen layer, and the plate surface temperature after exiting the liquid nitrogen spraying treatment chamber is -10℃. If the temperature is too low, the coating speed is adjusted to increase the plate temperature after liquid nitrogen spraying. If the temperature is still too low, the hardened layer on the plate surface will be thick, resulting in more powder after curing and drying. The lead paste application speed of the negative plate strip is adjusted to 17 m / min, and the plate surface temperature after liquid nitrogen spraying treatment chamber is measured again to be -5.5℃. Mass production then commences.

[0031] The electrode plates from the liquid nitrogen treatment chamber are cut into small pieces and stacked directly on the curing rack. The electrode plates are then placed in the curing chamber for curing and drying to complete the manufacturing of the negative electrode plates.

[0032] The positive and negative plates obtained above are assembled, acid is added, and the battery is charged to produce a 6-DZF-21 battery.

[0033] Example 3 After applying lead paste to the 6-DZF-23 continuous casting and coating strip at a speed of 17 m / min, it enters a semi-sealed liquid nitrogen spraying treatment chamber for double-sided liquid nitrogen spraying treatment. The single nozzle spraying speed is set to 100 L / h, the vertical distance between the nozzle and the electrode surface is set to 5 cm, and the actual cooling time of the liquid nitrogen spraying on the electrode is 1.5 s. It is checked that the electrode surface is cooled by the liquid nitrogen layer. After exiting the liquid nitrogen spraying treatment chamber, the surface temperature of the electrode is checked to be -4℃.

[0034] The electrode plates from the liquid nitrogen treatment chamber are cut into small pieces and stacked directly on the curing rack. The electrode plates are then placed in the curing chamber for curing and drying to complete the manufacturing of the positive electrode plates.

[0035] After applying lead paste to the 6-DZF-23 continuous casting and coating negative plate at a speed of 18 m / min, it enters a semi-sealed liquid nitrogen spraying treatment chamber for double-sided liquid nitrogen spraying treatment. The single nozzle spraying speed is set to 90 L / h, the vertical distance between the nozzle and the electrode surface is set to 8 cm, and the actual cooling time of the electrode plate after liquid nitrogen spraying is 1.5 s. After exiting the liquid nitrogen spraying treatment chamber, the surface temperature of the electrode plate is checked and found to be -6℃. The electrode plate exiting the liquid nitrogen spraying treatment chamber is cut into small pieces and directly stacked on a curing rack. The electrode plate is then placed in the curing chamber, and it is checked that the electrode plate is cooled by the liquid nitrogen surface. After curing and drying, the manufacturing of the negative electrode plate is completed.

[0036] The positive and negative plates obtained above are assembled, acid is added, and the battery is charged to produce a 6-DZF-23 battery.

[0037] Comparative Example 1 After applying lead paste to the 6-DZF-20 continuous casting and coating positive plate strip at a speed of 15 m / min, the coating paper is placed on the front and back surfaces of the plate. The plate is then cut into small pieces, surface dried at 180°C, stacked on a curing rack, and placed in a curing chamber for curing and drying to complete the manufacturing of the positive plate.

[0038] After applying lead paste to the 6-DZF-20 continuous casting and coating negative plate at a speed of 17 m / min, the coating paper is placed on the front and back surfaces of the electrode plate. The electrode plate is then cut into small pieces, surface dried at 150℃, stacked on a curing rack, and placed in a curing chamber for curing and drying to complete the manufacturing of the negative electrode plate.

[0039] The positive and negative plates obtained above are assembled, acid is added, and the battery is charged to produce a 6-DZF-20 battery.

[0040] Comparative Example 2 After applying lead paste to the 6-DZF-21 continuous casting and coating positive plate strip at a speed of 12m / min, the coating paper is placed on the front and back surfaces of the plate. The plate is then cut into small pieces, surface dried at 180℃, stacked on a curing rack, and placed in a curing chamber for curing and drying to complete the manufacturing of the positive plate.

[0041] After applying lead paste to the 6-DZF-21 continuous casting and coating negative plate at a speed of 12 m / min, the coating paper is placed on the front and back surfaces of the electrode plate. The electrode plate is then cut into small pieces, surface dried at 150℃, stacked on a curing rack, and placed in a curing chamber for curing and drying to complete the manufacturing of the negative electrode plate.

[0042] The positive and negative plates obtained above are assembled, acid is added, and the battery is charged to produce a 6-DZF-21 battery.

[0043] Comparative Example 3 After applying lead paste to the 6-DZF-23 continuous casting and coating positive plate strip at a speed of 17 m / min, the coating paper is placed on the front and back surfaces of the plate. The plate is then cut into small pieces, surface dried at 180°C, stacked on a curing rack, and placed in a curing chamber for curing and drying to complete the manufacturing of the positive plate.

[0044] After applying lead paste to the 6-DZF-23 continuous casting and coating negative plate at a speed of 18 m / min, the coating paper is placed on the front and back surfaces of the electrode plate. The electrode plate is then cut into small pieces, surface dried at 150℃, stacked on a curing rack, and placed in a curing chamber for curing and drying to complete the manufacturing of the negative electrode plate.

[0045] The positive and negative plates obtained above are assembled, acid is added, and the battery is charged to produce a 6-DZF-23 battery.

[0046] Detection Example 1 (1) Water absorption rate test In Examples 1-3 and Comparative Examples 1-3, the water absorption rate of the electrode plates was tested. The electrode plates, after having their surface coating removed, were dried at a constant temperature for 2 hours, and their weight was recorded. Then, the electrode plates were immersed in pure water for 2 hours, removed, and left to stand upright for 5 minutes. The weight of the electrode plates was recorded again, and the water absorption rate was calculated as follows: Water absorption rate = (Weight of electrode plate after water absorption - Weight of electrode plate after drying) / (Weight of electrode plate after drying - Weight of grid) × 100%. Relevant data are shown in Table 1.

[0047] Table 1 (2) Capacity test The 12V batteries prepared in Examples 1, 2, and 3 and Comparative Examples 1, 2, and 3 were subjected to capacity tests. The batteries were discharged to 10.50V at 10A and then charged at a constant voltage of 14.80V with a current limit of 5.0A for 7 hours as one cycle. The discharge time of the first three cycles was recorded (Table 2).

[0048] Table 2 Based on the water absorption data, the average water absorption rate of the positive bio-plate lead paste prepared in Examples 1, 2, and 3 was 9.94 g / g, while the average water absorption rate of the positive bio-plate lead paste prepared in Comparative Examples 1, 2, and 3 was 9.00 g / g; the average water absorption rate of the negative bio-plate lead paste prepared in Examples 1, 2, and 3 was 10.01 g / g, while the average water absorption rate of the negative bio-plate lead paste prepared in Comparative Examples 1, 2, and 3 was 9.10 g / g; a high water absorption rate of the lead paste indicates a high porosity of the electrode plate.

[0049] Based on the capacity testing data, the average capacity of the batteries prepared by the positive and negative plates in Examples 1, 2, and 3 was 10A discharge for 127.73 minutes, which was significantly higher than the average discharge for 122.53 minutes of the batteries prepared by Comparative Examples 1, 2, and 3.

[0050] The above data demonstrate that the battery prepared using this invention can improve the porosity of the electrode plates and enhance the battery's discharge capacity.

Claims

1. A method for manufacturing lead-acid battery plates, wherein the plates are produced by continuous casting and coating without a coating film, characterized in that, The coated electrode plates are cooled by spraying liquid nitrogen to rapidly cool them to -6 to -3°C.

2. The method for manufacturing lead-acid battery plates according to claim 1, characterized in that, The liquid nitrogen cooling time is 1.0~1.5 seconds.

3. The method for manufacturing lead-acid battery plates according to claim 1, characterized in that, Control the smearing speed to 12~18 meters / minute.

4. The method for manufacturing lead-acid battery plates according to claim 1, characterized in that, When using liquid nitrogen for cooling, the nozzle spray rate is 60~100L / h.

5. The method for manufacturing lead-acid battery plates according to claim 4, characterized in that, When using liquid nitrogen for cooling, the vertical distance between the nozzle and the electrode surface is 5-8 cm.

6. The method for manufacturing lead-acid battery plates according to claim 1, characterized in that, The temperature of the electrode plate is monitored after cooling with liquid nitrogen. If the electrode plate temperature is higher than -3℃, the coating speed is reduced; if the electrode plate temperature is lower than -6℃, the coating speed is increased.

7. The method for manufacturing lead-acid battery plates according to claim 1, characterized in that, After being cooled by liquid nitrogen spraying, the electrode plates produced by continuous casting and coating are slit into individual electrode plates. The individual electrode plates are then stacked on a curing rack and placed in a curing chamber for curing and drying to complete the electrode plate manufacturing process.

8. The method for manufacturing lead-acid battery plates according to claim 1, characterized in that, The electrode plate can be a positive electrode plate or a negative electrode plate.

9. A lead-acid battery plate, characterized in that, Prepared by the lead-acid battery electrode plate manufacturing method according to any one of claims 1 to 8.

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