Lead-carbon battery negative electrode lead paste formula and preparation method thereof, and lead-carbon battery negative electrode plate

Abstract

The invention provides a lead-carbon battery negative electrode lead paste formula, which comprises lead powder, dilute sulphuric acid, pure water and an additive, and every 1000 parts by mass of lead powder comprises 6-8 parts by mass of precipitated barium sulfate; 2 to 2.5 parts of sodium lignosulfonate; 1 to 2 parts of nano graphene; 5 to 10 parts of nano rice husk carbon black; 3 to 5 parts of a nano microporous ethylene-tetrafluoroethylene copolymer; 1.5 to 3 parts of indium carbonate; 1.5 to 3 parts of gallium carbonate; and 1-1.5 parts of polyester staple fiber. According to the invention, indium carbonate and gallium carbonate are adopted as hydrogen evolution inhibitors, so that the effect of inhibiting hydrogen evolution can be achieved more quickly, rice husk carbon and ETFE are adopted as configuration substances of the porous polar plate, the pore diameter and the pore pattern of the negative plate are more stable, the charge-discharge stability of the polar plate in the use process is improved, the polar plate is prevented from shrinking too early, and the capacity and the service life of the polar plate are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of lead-carbon batteries, and particularly relates to a formula of lead-carbon battery negative electrode lead paste and a preparation method thereof, and a lead-carbon battery negative electrode plate. Background Art

[0002] By adding carbon materials to the negative electrode of traditional lead-acid batteries, lead-carbon batteries can effectively delay the decline in discharge capacity of the battery caused by sulfation of the negative electrode, thereby enhancing the cycle stability of the battery.

[0003] While adding carbon materials can improve the charging efficiency and cycle life of lead-acid batteries, they also have some negative side effects. Carbon's low hydrogen evolution overpotential can cause severe hydrogen evolution side reactions in lead-acid batteries at the end of charging, leading to electrolyte depletion and even thermal runaway. Furthermore, hydrogen evolution produces acid mist, which can corrode surrounding equipment. Currently, methods for modifying carbon materials to further improve battery performance include heteroatom doping, chemical deposition of metal compounds, and lead-carbon composite materials.

[0004] Patent application publication number CN116454218A discloses a method for preparing lead paste for lead-carbon battery negative electrodes, comprising: preparing an activated carbon composite material by ball milling and precipitation of activated carbon particles, metallic indium, and gallium oxide powder. This invention utilizes indium and gallium oxide to produce an activated carbon composite material through an internal reaction, which generates indium oxide. The indium oxide enhances the ability to neutralize released hydrogen, while the gallium oxide enhances the flow of internal current, thereby inhibiting hydrogen evolution from the negative electrode plate. However, the reaction rate of indium and gallium oxides with dilute sulfuric acid is not fast enough to effectively inhibit hydrogen evolution.

[0005] During the charge and discharge process of lead-acid batteries, the plates expand and contract, which can easily cause active material to shed, shortening the battery's cycle life. Patent application CN102074703A discloses a negative electrode lead paste for lead-carbon super batteries and its preparation method. The paste's solid raw materials primarily consist of 1-93% lead powder and 2-95% lead-carbon composite material. The addition of the lead-carbon composite material enhances the interfacial bonding strength between the carbon material and the lead powder, effectively suppressing the volume shrinkage of the negative electrode active material during charge and discharge. However, there is still room for improvement in terms of improving the shrinkage state and stability of the negative plate. Summary of the Invention

[0006] In order to solve the above-mentioned technical problems existing in the prior art, the present invention provides a lead-carbon battery negative electrode lead paste formula and a preparation method thereof, and a lead-carbon battery negative electrode plate, which can inhibit hydrogen evolution more quickly, and the pore size and pore shape of the negative electrode plate are more stable, thereby improving the charge and discharge stability of the electrode plate during use, avoiding premature shrinkage of the electrode plate, and increasing the capacity and life of the electrode plate.

[0007] The invention provides a formula for a negative electrode lead paste of a lead-carbon battery. The formula comprises lead powder, dilute sulfuric acid, pure water and additives. Calculated by mass, for every 1000 parts of lead powder, the additives comprise: 6-8 parts of precipitated barium sulfate; 2-2.5 parts of sodium lignin sulfonate; 1-2 parts of nanographene; 5-10 parts of nano-rice husk carbon black; 3-5 parts of nanoporous ethylene-tetrafluoroethylene copolymer; 1.5-3 parts of indium carbonate; 1.5-3 parts of gallium carbonate; and 1-1.5 parts of polyester staple fibers.

[0008] Preferably, by mass, every 1000 parts of lead powder corresponds to 75-90 parts of the dilute sulfuric acid, and every 1000 parts of lead powder corresponds to 110-125 parts of the pure water.

[0009] Preferably, per 1000 parts of lead powder, the following components are used: 7 parts precipitated barium sulfate, 2.2 parts sodium lignin sulfonate, 2 parts nanographene, 10 parts nano-rice husk carbon black, 5 parts nanoporous ethylene-tetrafluoroethylene copolymer, 3 parts indium carbonate, 3 parts gallium carbonate, 1.5 parts polyester staple fibers, 90 parts dilute sulfuric acid, and 125 parts pure water. This formulation significantly improves the capacity, lifespan, and low-temperature charge and discharge capabilities of lead-carbon batteries.

[0010] Nano-rice husk carbon black contains a certain amount of SiO2. While nano-rice husk carbon black itself has a certain degree of conductivity, the presence of SiO2 improves the contact between carbon black particles, forming a more efficient conductive network that facilitates smoother electron transfer within the battery, thereby reducing the battery's internal resistance and improving its charge and discharge efficiency. The high SiO2 content in nano-rice husk carbon black increases the specific surface area of the electrode material, facilitating full utilization of the active material and thereby increasing the battery's capacity. Furthermore, SiO2 inhibits the shedding and aggregation of active materials during the battery's charge and discharge processes, maintaining a well-dispersed state. This further improves the battery's charge and discharge efficiency and reversibility, ultimately enhancing its overall performance.

[0011] Preferably, the oxidation degree of the lead powder is 73%-80%, the length of the polyester staple fiber is 3-5 mm, and the density of the dilute sulfuric acid is 1.4 g / cm 3 .

[0012] The present invention also provides a method for preparing the above-mentioned lead-carbon battery negative electrode lead paste, comprising the following steps:

[0013] (1) mixing and stirring the formulated amount of nanographene, nanoporous ethylene-tetrafluoroethylene copolymer, nano rice husk carbon black, and a portion of the formulated amount of dilute sulfuric acid to prepare slurry A;

[0014] (2) dry-mixing the formulated amount of lead powder, precipitated barium sulfate, sodium lignin sulfonate, indium carbonate, gallium carbonate, and polyester staple fibers, and then adding the formulated amount of pure water and wet-mixing to obtain slurry B;

[0015] (3) Add slurry A to slurry B, cool it to below 45°C, then add the remaining amount of dilute sulfuric acid and stir until the lead paste density is between 4.4 and 4.5 g / cm 3 .

[0016] Preferably, in step (1), the stirring speed is 300-500 r / min, and the stirring time is 30-50 min.

[0017] Preferably, in step (2), the dry mixing time is 5 minutes, and the wet mixing time is 5 minutes.

[0018] Preferably, in step (3), the stirring time is 10 minutes.

[0019] The present invention also provides a lead paste for the negative electrode of a lead-carbon battery prepared by the above preparation method.

[0020] The present invention also provides a lead-carbon battery negative plate, which is prepared by coating the lead-carbon battery negative electrode lead paste on a negative electrode grid.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) Nanoporous ethylene-tetrafluoroethylene copolymer is a chemical corrosion-resistant material with porosity and mechanical toughness. It can provide a stable porous structure for the negative plate, improve the utilization rate of active substances, and delay the shrinkage time of the negative plate due to its stable chemical structure. Rice husk carbon and ETFE are used as the structural materials of the porous plate. The plate pore size and pore shape are more stable, which improves the charge and discharge stability of the plate during use, avoids premature shrinkage of the plate, and increases the plate capacity and life.

[0023] (2) Indium carbonate and gallium carbonate are used as hydrogen evolution inhibitors. Compared with the use of indium and gallium oxides, the chemical reaction between indium and gallium carbonates and dilute sulfuric acid is faster, which can play the effective role of hydrogen evolution inhibitors more quickly, while improving the uniformity of the hydrogen evolution inhibitor content in each plate. DETAILED DESCRIPTION

[0024] Example 1

[0025] (1) Prefabrication of Mixture A

[0026] 1 part of graphene (parts by mass, the same below), 3 parts of nanoporous ETFE (particle size less than 1 μm, hardness of D60, density of 1.7-1.8 g / ml, the same below) and 5 parts of nano rice husk carbon black were poured into a high-speed shear mixer, and then 30 parts of dilute sulfuric acid (density 1.4 g / cm 3 , the same below), turn on the high-speed stirrer, adjust the speed to 300r / min, and stir at high speed for 30min to obtain a mixture slurry A.

[0027] (2) Lead paste production process

[0028] Put 1000 parts of lead powder (oxidation degree of 73%) into the paste making machine, then put in 6 parts of precipitated barium sulfate, 2 parts of sodium lignin sulfonate, 1.5 parts of gallium carbonate, 1.5 parts of indium carbonate, and 1 part of polyester staple fiber (length of 3-5mm, the same below), close the paste making machine door, and dry stir for 5 minutes. Then pour in 110 parts of pure water for 5 minutes, and continue stirring for 5 minutes. Then pour in mixture A for 2 minutes, and at the same time open the cooling circulating water system and air cooling system to cool down to below 45°C, then pour in 45 parts of dilute sulfuric acid for 8 minutes, and continue stirring for 10 minutes. Stop the machine to test the lead paste specific gravity at 4.4-4.5g / cm 3 If the lead paste is too thick, continue stirring until the specific gravity of the lead paste is between 4.4 and 4.5 g / cm 3 Only then can it end.

[0029] Example 2

[0030] (1) Prefabrication of Mixture A

[0031] Pour 1.5 parts of graphene, 4 parts of nanoporous ETFE and 8 parts of nano rice husk carbon black into a high-speed shear mixer, then add 30 parts of dilute sulfuric acid, turn on the high-speed mixer, adjust the speed to 400 r / min, and stir at high speed for 40 minutes to obtain a mixture slurry A.

[0032] (2) Lead paste production process

[0033] Put 1000 parts of lead powder (oxidation degree of 73%) into the paste making machine, then put in 7 parts of precipitated barium sulfate, 2.2 parts of sodium lignin sulfonate, 2 parts of gallium carbonate, 2 parts of indium carbonate, and 1.2 parts of polyester staple fiber, close the paste making machine door, and dry stir for 5 minutes. Then pour in 118 parts of pure water for 5 minutes, and continue stirring for 5 minutes. Then pour in mixture A for 2 minutes, and at the same time open the cooling circulating water system and air cooling system to cool down to below 45°C, then pour in 50 parts of dilute sulfuric acid for 8 minutes, and continue stirring for 10 minutes. Stop the machine to test the lead paste specific gravity at 4.4-4.5g / cm 3 If the lead paste is too thick, continue stirring until the specific gravity of the lead paste is between 4.4 and 4.5 g / cm3 Only then can it end.

[0034] Example 3

[0035] (1) Prefabrication of Mixture A

[0036] Pour 2 parts of graphene, 5 parts of nanoporous ETFE and 10 parts of nano rice husk carbon black into a high-speed shear mixer, then add 30 parts of dilute sulfuric acid, turn on the high-speed mixer, adjust the speed to 500 r / min, and stir at high speed for 50 minutes to obtain a mixture slurry A.

[0037] (2) Lead paste production process

[0038] Put 1000 parts of lead powder (oxidation degree is 80%) into the paste making machine, then put in 8 parts of precipitated barium sulfate, 2.5 parts of sodium lignin sulfonate, 3 parts of gallium carbonate, 3 parts of indium carbonate, and 1.5 parts of polyester staple fiber, close the paste making machine door, and dry stir for 5 minutes. Then pour in 125 parts of pure water for 5 minutes, and continue stirring for 5 minutes. Then pour in mixture A for 2 minutes, and at the same time open the cooling circulating water system and air cooling system to cool down to below 45°C, then pour in 60 parts of dilute sulfuric acid for 8 minutes, and continue stirring for 10 minutes. Stop the machine to test the lead paste specific gravity at 4.4-4.5g / cm 3 If the lead paste is too thick, continue stirring until the specific gravity of the lead paste is between 4.4 and 4.5 g / cm 3 Only then can it end.

[0039] Comparative Example 1

[0040] Place 1000 parts of lead powder (oxidation degree of 75%) into a paste making machine, then add 7 parts of precipitated barium sulfate, 2.2 parts of sodium lignin sulfonate, 2.5 parts of acetylene carbon black, and 1.2 parts of polyester staple fiber. Close the paste making machine door and dry-mix for 5 minutes. Then pour in 118 parts of pure water for 5 minutes and continue mixing for 5 minutes. At the same time, turn on the cooling circulating water system and air cooling system to cool down to below 45°C. Then pour in 85 parts of dilute sulfuric acid for 8 minutes and continue mixing for 10 minutes. Stop the machine to test the lead paste specific gravity at 4.4-4.5g / cm 3 If the lead paste is too thick, continue stirring until the specific gravity of the lead paste is between 4.4 and 4.5 g / cm 3 Only then can it end.

[0041] Comparative Example 2

[0042] (1) Prefabrication of Mixture A

[0043] Pour 1.5 parts of graphene and 8 parts of nano rice husk carbon black into a high-speed shear mixer with a volume of 60 to 100 parts of water, then add 30 parts of dilute sulfuric acid, turn on the high-speed mixer, adjust the speed to 400 r / min, and stir at high speed for 40 minutes to obtain a mixture slurry A.

[0044] (2) Lead paste production process

[0045] Put 1000 parts of lead powder (oxidation degree of 75%) into the paste making machine, then put in 7 parts of precipitated barium sulfate, 2.2 parts of sodium lignin sulfonate, 2.5 parts of gallium carbonate, 2 parts of indium carbonate, and 1.2 parts of polyester staple fiber, close the paste making machine door, and dry stir for 5 minutes. Then pour in 118 parts of pure water for 5 minutes, and continue stirring for 5 minutes. Then pour in mixture A for 2 minutes, and at the same time open the cooling circulating water system and air cooling system to cool down to below 45°C, then pour in 55 parts of dilute sulfuric acid for 8 minutes, and continue stirring for 10 minutes. Stop the machine to test the lead paste specific gravity at 4.4-4.5g / cm 3 If the lead paste is too thick, continue stirring until the specific gravity of the lead paste is between 4.4 and 4.5 g / cm 3 Only then can it end.

[0046] Comparative Example 3

[0047] (1) Prefabrication of Mixture A

[0048] Pour 1.5 parts of graphene, 4 parts of nanoporous ETFE and 8 parts of nano rice husk carbon black into a high-speed shear mixer with a volume of 60 to 100 parts of water, then add 30 parts of dilute sulfuric acid, turn on the high-speed mixer, adjust the speed to 400 r / min, and stir at high speed for 40 minutes to obtain a mixture slurry A.

[0049] (2) Lead paste production process

[0050] Put 1000 parts of lead powder (oxidation degree of 75%) into the paste making machine, then put in 7 parts of precipitated barium sulfate, 2.2 parts of sodium lignin sulfonate, 2.5 parts of gallium carbonate, and 1.2 parts of polyester staple fiber. Close the paste making machine door and dry stir for 5 minutes. Then pour in 118 parts of pure water for 5 minutes and continue stirring for 5 minutes. Then pour in mixture A for 2 minutes. At the same time, open the cooling circulating water system and air cooling system to cool down to below 45°C. Then pour in 55 parts of dilute sulfuric acid for 8 minutes and continue stirring for 10 minutes. Stop the machine to test the lead paste specific gravity at 4.4-4.5g / cm 3 If the lead paste is too thick, continue stirring until the specific gravity of the lead paste is between 4.4 and 4.5 g / cm 3 Only then can it end.

[0051] Comparative Example 4

[0052] (1) Prefabrication of Mixture A

[0053] Pour 1.5 parts of graphene, 4 parts of nanoporous ETFE and 8 parts of nano rice husk carbon black into a high-speed shear mixer with a volume of 60 to 100 parts of water, then add 30 parts of dilute sulfuric acid, turn on the high-speed mixer, adjust the speed to 400 r / min, and stir at high speed for 40 minutes to obtain a mixture slurry A.

[0054] (2) Lead paste production process

[0055] Put 1000 parts of lead powder into the paste making machine, then put in 7 parts of precipitated barium sulfate, 2.2 parts of sodium lignin sulfonate, 2 parts of indium carbonate, and 1.2 parts of polyester staple fiber. Close the paste making machine door and dry-mix for 5 minutes. Then pour in 118 parts of pure water for 5 minutes and continue to stir for 5 minutes. Then pour in mixture A for 2 minutes. At the same time, open the cooling circulating water system and air cooling system to cool down to below 45°C. Then pour in 55 parts of dilute sulfuric acid for 8 minutes and continue to stir for 10 minutes. Stop the machine to test the lead paste density at 4.4-4.5g / cm 3 If the lead paste is too thick, continue stirring until the specific gravity of the lead paste is between 4.4 and 4.5 g / cm 3 Only then can it end.

[0056] Negative plates were prepared using the negative lead pastes in the embodiments and comparative examples, and assembled into 6-DZF-20 batteries for testing. The test results are shown in Table 1.

[0057] (1) 2h rate discharge (normal temperature capacity): According to Article 5.5 of the national battery standard GB / T22199-2017, after the battery is fully charged, it should be kept at a temperature of 25±2℃ for 1 to 24 hours, and discharged at a constant current of 10A until the battery voltage reaches 10.5V. The 2h rate capacity Ca should reach the C2 standard within three cycles.

[0058] (2) Low-temperature, high-current discharge: According to Article 5.9 of the national battery standard GB / T22199-2017, the battery was placed in a low-temperature box at -18°C for 12 hours, and then discharged at a current of 10A in a -18°C environment. The discharge was terminated when the battery voltage reached 10.5V, and the average discharge time was recorded.

[0059] (3) Cycle life: According to Article 5.12 of the national battery standard GB / T22199-2017, in an environment with a temperature of 25±5℃, discharge at a current of 10A for 1.6h, and then charge at a constant voltage of 16V (current limit 4A) for 6.4h as one cycle. When the terminal voltage of the battery is lower than 10.5V for three consecutive times after discharging for 1.6h, the battery cycle life is terminated. The total cycle life is not less than 350 times.

[0060] (4) Weigh the water loss of the battery after 300 cycles.

[0061] Table 1

[0062] Test samples Normal temperature capacity / min -10℃ low temperature capacity / min Number of cycles / times Water loss / g Example 1 136 106 390 45 Example 2 139 111 415 41 Example 3 141 112 420 37 Comparative Example 1 122 94 360 60 Comparative Example 2 124 96 368 55 Comparative Example 3 126 98 375 58 Comparative Example 4 129 96 372 60

[0063] From the above test data, it can be seen that the addition of rice husk carbon black and ETFE will affect the product capacity and life by more than 10%, and the addition of indium carbonate and gallium carbonate will affect the water loss by more than 30%. Rice husk carbon black, ETFE, gallium carbonate and indium carbonate have a huge impact on the capacity, life, low-temperature charge and discharge capabilities and hydrogen evolution potential of battery products.

Claims

1. A lead paste formula for a lead-carbon battery negative electrode, comprising lead powder, dilute sulfuric acid, pure water and additives, characterized in that: Calculated by mass, the additives corresponding to every 1,000 parts of lead powder include: precipitated barium sulfate, 6-8 parts; sodium lignin sulfonate, 2-2.5 parts; nano-graphene, 1-2 parts; nano-rice husk carbon black, 5-10 parts; nano-microporous ethylene-tetrafluoroethylene copolymer, 3-5 parts; indium carbonate, 1.5-3 parts; gallium carbonate, 1.5-3 parts; and polyester staple fiber, 1-1.5 parts.

2. The lead-carbon battery negative electrode lead paste formula according to claim 1, characterized in that: By mass, every 1000 parts of lead powder corresponds to 75-90 parts of the dilute sulfuric acid, and every 1000 parts of lead powder corresponds to 110-125 parts of the pure water.

3. The lead-carbon battery negative electrode lead paste formula according to claim 1, characterized in that: In terms of mass, every 1000 parts of lead powder corresponds to 7 parts of precipitated barium sulfate, 2.2 parts of sodium lignin sulfonate, 2 parts of nano-graphene, 10 parts of nano-rice husk carbon black, 5 parts of nano-microporous ethylene-tetrafluoroethylene copolymer, 3 parts of indium carbonate, 3 parts of gallium carbonate, 1.5 parts of polyester staple fiber, 90 parts of dilute sulfuric acid and 125 parts of pure water.

4. A method for preparing a negative electrode lead paste for a lead-carbon battery, characterized in that: Using the lead-carbon battery negative electrode lead paste formula according to any one of claims 1 to 3, the preparation method comprises the following steps: (1) mixing and stirring the formulated amount of nanographene, nanoporous ethylene-tetrafluoroethylene copolymer, nano rice husk carbon black, and a portion of the formulated amount of dilute sulfuric acid to prepare slurry A; (2) dry-mixing the formulated amount of lead powder, precipitated barium sulfate, sodium lignin sulfonate, indium carbonate, gallium carbonate, and polyester staple fibers, and then adding the formulated amount of pure water and wet-mixing to obtain slurry B; (3) Add slurry A to slurry B, cool it to below 45°C, then add the remaining amount of dilute sulfuric acid and stir until the lead paste density is between 4.4 and 4.5 g / cm 3 .

5. The preparation method according to claim 3, characterized in that In step (1), the stirring speed is 300-500 r / min, and the stirring time is 30-50 min.

6. The preparation method according to claim 3, characterized in that In step (2), the dry mixing time is 5 minutes, and the wet mixing time is 5 minutes.

7. The preparation method according to claim 3, characterized in that In step (3), the stirring time is 10 min.

8. A lead paste for negative electrode of a lead-carbon battery prepared by the preparation method according to any one of claims 4 to 7.

9. A lead-carbon battery negative plate, characterized in that: The lead-carbon battery negative electrode lead paste according to claim 8 is coated on the negative electrode grid to prepare the lead-carbon battery negative electrode lead paste.