Continuous coating process for valve-regulated lead-acid storage battery layered apparent specific gravity polar plate by using continuous casting and rolling grid

Abstract

The invention discloses a continuous coating process for a valve-regulated lead-acid storage battery layered apparent specific gravity polar plate by using a continuous casting and rolling grid. The continuous coating process comprises the following specific steps: step 1, preparing the continuous casting and rolling grid: preparing a lead alloy grid by adopting a continuous casting and rolling process; step 2, first coating section: the grid enters a first plate coating machine to form an inner layer; step 3, a second coating section: the grid belt directly enters a second plate coating machine; 4, board paper coating: covering the surface of the pole plate subjected to double-layer coating with board paper to enhance the strength of the pole plate and facilitate subsequent treatment; 5, sheet collection: cutting the continuous polar plate belt coated with the paperboard into single sheets, and collecting the single sheets; 6, rapid surface drying: the single polar plate enters a rapid surface drying kiln; 7, secondary sheet collection: collecting the surface-dried polar plate through a secondary sheet collection device, and entering a subsequent curing process; through the layered structure design, the influence of polar plate surface argillization on the utilization rate of internal active substances is delayed, and the cycle life of the battery is prolonged.

Description

Technical Field

[0001] This invention relates to the field of lead-acid battery technology, specifically to a continuous casting and rolling grid for continuous coating of layered apparent gravity plates in valve-regulated lead-acid batteries. Background Technology

[0002] Valve-regulated lead-acid batteries are important energy storage devices widely used in power, communications, UPS and other fields. As the core component of the battery, the manufacturing process of the electrode plates directly affects the battery's performance and lifespan.

[0003] Currently, lead-acid battery plates are mainly manufactured using two process routes: the traditional casting grid coating process and the continuous casting and rolling grid coating process. Continuous casting and rolling grids are widely used in large-scale production due to their advantages such as high production efficiency, high material utilization, and good grid strength. However, existing continuous casting and rolling grid coating processes mainly use a single coating method, which cannot achieve differentiated design between inner and outer layers.

[0004] Recent studies have shown that during the use of lead-acid batteries, the lead paste on the outside of the plates first becomes muddy, forming a dense layer that hinders the penetration of electrolyte into the interior and the transfer of electrons. As a result, although the internal lead paste is in good condition, it cannot be fully utilized. Although layered apparent gravity plate designs can solve this problem, existing technologies are mostly based on traditional grids and discontinuous processes, which cannot adapt to the continuous and efficient production characteristics of continuous casting and rolling grids.

[0005] Therefore, it is necessary to develop a continuous coating process for layered apparent gravity plates suitable for continuous casting and rolling grids, which can achieve differentiated design of inner and outer layers while maintaining high efficiency in continuous production. Summary of the Invention

[0006] The purpose of this invention is to provide a continuous coating process for layered apparent gravity plates in valve-regulated lead-acid batteries using continuously cast and rolled grids. The specific steps are as follows:

[0007] Step 1: Preparation of lead alloy grids by continuous casting and rolling: Lead alloy grids are prepared by continuous casting and rolling process;

[0008] Step 2: First coating section: The grid enters the first coating machine and is coated with high apparent density lead paste, which is 4.4-4.7 g / cm³, to form the inner layer;

[0009] Step 3: Second coating section: The grid belt directly enters the second coating machine, where a low apparent density lead paste, i.e., 4.0-4.3 g / cm³, is applied, and a pressure of 0.3-0.5 MPa is applied to ensure good bonding between the two layers of lead paste to form the outer layer;

[0010] Step 4: Covering with paperboard: Covering the surface of the double-coated electrode with paperboard to enhance the strength of the electrode and facilitate subsequent processing;

[0011] Step 5: Collecting the sheets: Cut the continuous electrode strip covered with paper into individual sheets and collect them;

[0012] Step 6: Rapid surface drying: A single electrode plate enters a rapid surface drying kiln at a temperature of 65-80℃ for a residence time of 10-15 seconds to allow the electrode plate surface to dry initially.

[0013] Step 7: Secondary collection: After surface drying, the electrode plates are collected by a secondary collection device and enter the subsequent curing process.

[0014] Preferably, the thickness of the lead paste in the first coating section is 0.8-1.2 mm.

[0015] Preferably, the thickness of the lead paste in the second coating section is 0.4-0.7 mm.

[0016] Preferably, the weight of the coated paperboard is 20-25 g / m².

[0017] Preferably, the rapid surface drying method employs infrared heating or a combination of hot air and infrared heating.

[0018] Preferably, an adhesion promoter is sprayed onto the surface of the lead paste before coating the paperboard to enhance the bonding between the paperboard and the lead paste.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] 1. It has enabled continuous production of layered apparent gravity plates for continuous casting and rolling, significantly improving production efficiency;

[0021] 2. By precisely controlling the temperature and humidity of the surface treatment section, a strong bond is ensured between the two layers of lead paste, preventing delamination and peeling.

[0022] 3. Through the layered structure design, the impact of mud formation on the surface of the electrode plates on the utilization rate of internal active materials is delayed, thereby improving the cycle life of the battery;

[0023] 4. It integrates processes such as continuous casting and rolling, continuous coating, slicing and surface drying, optimizes the production process, and reduces the intensity of manual operation. Attached Figure Description

[0024] Figure 1 A schematic diagram of the continuous coating process for layered apparent gravity electrode plates in continuous casting and rolling. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0026] Example 1

[0027] The continuous casting and rolling grid in this embodiment is used in the continuous coating process of layered apparent gravity plates for valve-regulated lead-acid batteries. The specific steps are as follows:

[0028] 1. Preparation of continuous casting and rolling grids:

[0029] Continuous casting and rolling production is carried out using lead alloy (Pb-Ca-Sn-Al alloy, Ca content 0.06-0.08%, Sn content 0.6-0.8%, Al content 0.01-0.02%).

[0030] The continuous rolling temperature is controlled at 320-340℃, and the rolling pressure is 12-15MPa;

[0031] A continuous plate grid strip with a thickness of 0.8 mm and a width of 300 mm was produced;

[0032] 2. First coating section:

[0033] Inner layer lead paste formula: 100 parts by weight of lead powder, 10 parts by weight of sulfuric acid, 6 parts by weight of water, 0.2 parts by weight of cellulose, and 0.1 parts by weight of carbon black;

[0034] Adjust the inner layer of lead paste to a specific gravity of 4.6 g / cm³;

[0035] The grid belt passes through the first coating machine at a speed of 5-8 m / min, and is coated with an inner layer of high apparent density lead paste with a thickness of 1.0 mm.

[0036] 3. Second coating section:

[0037] The outer layer of lead paste formula is as follows: 100 parts by weight of lead powder, 8 parts by weight of sulfuric acid, 8 parts by weight of water, 0.3 parts by weight of cellulose, and 0.15 parts by weight of carbon black.

[0038] Adjust the outer layer of lead paste to a specific gravity of 4.2 g / cm³;

[0039] The grid belt passes directly through the second coating machine to be coated with an outer layer of low apparent gravity lead paste with a thickness of 0.5 mm;

[0040] During the coating process, the pressure of the coating machine is controlled at 0.4MPa to ensure good bonding between the two layers of lead paste;

[0041] 4. Coated paperboard:

[0042] A layer of paper is placed over the surface of the electrode plate after double coating, and a light pressure roller is used to bond the paper to the surface of the lead paste.

[0043] The paperboard weighs 20-25g / m² and has certain mechanical strength and air permeability;

[0044] 5. Retrieving the film:

[0045] The electrode strip covered with paperboard is cut into individual pieces according to a set size (e.g., 145mm×120mm) by a slitting device;

[0046] The slitting speed is synchronized with the coating speed to ensure continuous production;

[0047] The cut single electrode plates are collected via a conveyor belt;

[0048] 6. Rapid surface drying:

[0049] The collected single electrode plates enter a rapid surface drying kiln, which uses infrared heating.

[0050] The surface drying kiln temperature is controlled at 75℃, and the electrode plates remain in it for 12 seconds.

[0051] This stage allows the electrode surface to quickly reach a preliminary dry state, facilitating stacking and subsequent processing;

[0052] 7. Second film collection:

[0053] After surface drying, the electrode plates are conveyed into the palletizing system;

[0054] The plates are automatically stacked according to the preset number of layers and quantity;

[0055] After being stacked, the batches of electrode plates are transferred to the curing workshop by conveyor truck for subsequent curing treatment.

[0056] Example 2

[0057] The difference between this embodiment and Embodiment 1 is that:

[0058] 1. The thickness of the continuous casting and rolling grating is 0.9 mm, and the width is 350 mm;

[0059] 2. Adjust the inner layer of lead paste to 4.7 g / cm³ according to the specific gravity, and the coating thickness is 0.9 mm;

[0060] 3. The pressure of the second coating machine is adjusted to 0.45MPa to ensure better interlayer bonding;

[0061] 4. The weight of the covering paperboard is 22g / m², with a small amount of reinforcing fiber added;

[0062] 5. The temperature of the rapid surface drying kiln is adjusted to 78℃, and the residence time is shortened to 10 seconds;

[0063] 6. During the second collection of plates, a compaction and stacking method is adopted to improve the stability of plate stacking.

[0064] Example 3

[0065] The difference between this embodiment and Embodiment 1 is that:

[0066] 1. The grid alloy composition is adjusted to a Pb-Ca-Sn alloy, with a Ca content of 0.08-0.10% and a Sn content of 0.8-1.0%;

[0067] 2. The continuous rolling pressure is increased to 16-18 MPa to improve the strength of the slab;

[0068] 3. Adjust the inner layer of lead paste to 4.5 g / cm³ according to the specific gravity, and the coating thickness is 1.2 mm;

[0069] 4. Add 0.1 parts by weight of carboxymethyl cellulose as a binding agent to the outer layer of lead paste;

[0070] 5. Adjust the outer layer of lead paste to 4.3 g / cm³ according to its specific gravity, and the coating thickness should be 0.45 mm;

[0071] 6. Before coating the paperboard, spray a small amount of adhesion promoter on the surface of the lead paste to enhance the bond between the paperboard and the lead paste;

[0072] 7. The rapid surface drying process uses a combination of hot air and infrared heating, with the temperature controlled at 70℃ and the dwell time being 15 seconds.

[0073] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A continuous casting and rolling grid for continuous coating process of layered apparent gravity plates in valve-regulated lead-acid batteries, characterized in that: The specific steps are as follows: Step 1: Preparation of lead alloy grids by continuous casting and rolling: Lead alloy grids are prepared by continuous casting and rolling process; Step 2: First coating section: The grid enters the first coating machine and is coated with high apparent density lead paste, which is 4.4-4.7 g / cm³, to form the inner layer; Step 3: Second coating section: The grid belt directly enters the second coating machine, where a low apparent density lead paste, i.e., 4.0-4.3 g / cm³, is applied, and a pressure of 0.3-0.5 MPa is applied to ensure good bonding between the two layers of lead paste to form the outer layer; Step 4: Covering with paperboard: Covering the surface of the double-coated electrode with paperboard to enhance the strength of the electrode and facilitate subsequent processing; Step 5: Collecting the sheets: Cut the continuous electrode strip covered with paper into individual sheets and collect them; Step 6: Rapid surface drying: A single electrode plate enters a rapid surface drying kiln at a temperature of 65-80℃ for a residence time of 10-15 seconds to allow the electrode plate surface to dry initially. Step 7: Secondary collection: After surface drying, the electrode plates are collected by a secondary collection device and enter the subsequent curing process.

2. The continuous casting and rolling grid for continuous coating of layered apparent gravity plates in valve-regulated lead-acid batteries according to claim 1, characterized in that: The thickness of the lead paste in the first coating section is 0.8-1.2 mm.

3. The continuous casting and rolling grid for continuous coating of layered apparent gravity plates in valve-regulated lead-acid batteries according to claim 1, characterized in that: The thickness of the lead paste in the second coating section is 0.4-0.7 mm.

4. The continuous casting and rolling grid for continuous coating of layered apparent gravity plates in valve-regulated lead-acid batteries according to claim 1, characterized in that: The weight of the coated paperboard is 20-25 g / m².

5. The continuous casting and rolling grid for continuous coating of layered apparent gravity plates in valve-regulated lead-acid batteries according to claim 1, characterized in that: The rapid surface drying method employs infrared heating or a combination of hot air and infrared heating.

6. The continuous casting and rolling grid for continuous coating of layered apparent gravity plates in valve-regulated lead-acid batteries according to claim 1, characterized in that: Before coating the paperboard, spray an adhesion promoter onto the lead paste surface to enhance the bond between the paperboard and the lead paste.

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