Negative electrode lead paste capable of inhibiting hydrogen evolution and prolonging cycle life of battery, and preparation method therefor

Abstract

The present invention belongs to the technical field of lead-acid storage batteries. Disclosed is a negative electrode lead paste capable of inhibiting hydrogen evolution and prolonging the cycle life of a battery. The negative electrode lead paste comprises the following components: high-purity humic acid, sodium lignosulfonate, precipitated or superfine barium sulfate, carbon black, acetylene black, a graphite powder, modified graphene, zinc oxide, super-strong polyester staple fibers, a lead powder, dilute sulfuric acid and deionized water. A conventional blended paste fabrication process is not changed; by adding the modified graphene, the conductivity and dispersibility of graphene is improved; by adding the zinc oxide, not only is the hydrogen evolution reaction of a battery inhibited, but thermal passivation is also reduced; and lignin and humic acid also have the effect of inhibiting hydrogen evolution.

Description

Negative electrode lead paste for inhibiting hydrogen evolution and extending battery cycle life and preparation method thereof Technical Field

[0001] The present disclosure relates to the technical field of lead-acid batteries, and in particular to a negative electrode lead paste capable of inhibiting hydrogen evolution and extending the cycle life of a battery, and a preparation method thereof. Background Art

[0002] Lead-acid batteries are widely used in many fields, including power and grid energy, due to their mature technology, abundant raw materials, high lead recovery rates from waste battery processing, and low prices. However, they also suffer from drawbacks such as low specific energy and short cycle life. Lead-carbon batteries, which incorporate varying amounts of carbon into the negative electrode lead paste to increase conductivity and improve cycle life, also introduce new challenges, such as increased water loss. Therefore, inhibiting hydrogen evolution and reducing water loss have always been key technical challenges.

[0003] Application Contents

[0004] Provided is a lead-carbon negative electrode lead paste formula that inhibits battery hydrogen evolution and effectively extends the battery cycle life. The formula combines the dual advantages of adding modified graphene to increase cycle life and adding zinc oxide to inhibit battery hydrogen evolution, thereby improving cycle life and solving the problems mentioned in the above background. The technical solution disclosed herein is as follows: A negative electrode lead paste that inhibits hydrogen evolution and extends battery cycle life comprises the following components: high-purity humic acid, sodium lignin sulfonate, precipitated or ultrafine barium sulfate, carbon black, acetylene black, graphite powder, modified graphene, zinc oxide, super-strong polyester staple fibers, lead powder, dilute sulfuric acid, and deionized water.

[0005] As an improvement of the present disclosure, high-purity humic acid accounts for 3.0-5.5‰ of the weight of the lead powder, sodium lignin sulfonate accounts for 2-3.5‰ of the weight of the lead powder, precipitated or ultrafine barium sulfate accounts for 8-12‰ of the weight of the lead powder, carbon black accounts for 7-10‰ of the weight of the lead powder, acetylene black accounts for 1.5-3‰ of the weight of the lead powder, graphite powder accounts for 1.5-3‰ of the weight of the lead powder, modified graphene accounts for 0.1-0.5‰ of the weight of the lead powder, zinc oxide accounts for 0.2-0.5‰ of the weight of the lead powder, super-strong polyester staple fiber accounts for 0.5-1.0‰ of the weight of the lead powder, the lead powder is 1000 kg, dilute sulfuric acid accounts for 9-12% of the weight of the lead powder, and deionized water accounts for 11-13% of the weight of the lead powder.

[0006] As an improvement of the present disclosure, the specific surface area of ​​carbon black is 1000 to 1600 m 2 / g.

[0007] As an improvement of the present disclosure, the specific surface area of ​​acetylene black is 50 to 80 m 2 / g.

[0008] As an improvement of the present disclosure, the graphite powder has a particle size of 300 mesh or more.

[0009] As an improvement of the present disclosure, the fineness of the super-strong polyester staple fiber is 0.5D, and the length of the super-strong polyester staple fiber is 2 mm to 4 mm.

[0010] As an improvement of the present disclosure, the preparation step of the modified graphene includes: weighing double-layer graphene with D50 <10 μm and dimethylacetamide in proportion and adding them to a reaction container, ultrasonicating at 50-60° C. for 5 hours until the graphene is completely dispersed, and obtaining a modified graphene suspension.

[0011] As an improvement of the present disclosure, a method for preparing the negative electrode lead paste for inhibiting hydrogen evolution and extending the cycle life of the battery comprises the following steps:

[0012] 1) Disperse the formulated amount of sodium lignin sulfonate, high-purity humic acid, precipitated or ultrafine barium sulfate, zinc oxide, and super-strong polyester staple fiber (fineness 0.5D, length 3mm-5mm) evenly in the lead powder when making the lead paste, and dry-stir for about 5 minutes to mix evenly;

[0013] 2) Add the carbon black (specific surface area 1000~1600m 2 / g), acetylene black (specific surface area 50~80m 2 / g), graphite powder (particle size above 300 mesh), and modified graphene suspension are mixed evenly to form a suspension;

[0014] 3) Deionized water (about 11-13% by weight of lead powder) and the prepared carbon material suspension are quickly added to the lead powder mixed in step 1 and stirred for about 10 minutes;

[0015] 4) 9-12% of the weight of lead powder with a density of 1.3-1.35 g / cm 3 Slowly add dilute sulfuric acid to the lead paste obtained in step 3, and control the addition time to 10-15 minutes. Continue stirring for 8-12 minutes, and then lower the temperature to 55°C to measure the apparent density. The apparent density is controlled at 4.45±0.1g / cm 3 .

[0016] As an improvement of the present disclosure, as a new formula and process, the paste temperature is required to be controlled between 45 and 55°C to ensure that sufficient highly active substances are generated during the preparation process of the lead paste, and the oxidation degree of the lead powder is required to be 70% to 78%.

[0017] Compared with the prior art, the beneficial effects of the present disclosure are as follows: the present disclosure does not change the existing paste production process, the addition of modified graphene improves the conductivity and dispersibility of graphene, the addition of zinc oxide not only inhibits the hydrogen evolution reaction of the battery, but also reduces thermal passivation, and lignin and humic acid also have the effect of inhibiting hydrogen evolution. When combined, the hydrogen evolution inhibition effect is most effectively exerted, the cycle performance of the battery is improved, and the service life of the battery is extended. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG1 is a schematic diagram of a 2V6.8Ah water loss test in one embodiment;

[0019] FIG2 is a comparison diagram of the start-stop cycle life of 50% charged 4C2 in one embodiment. DETAILED DESCRIPTION

[0020] The following embodiments of the present disclosure are described in detail. The following embodiments are illustrative and are intended only to explain the present disclosure and are not to be construed as limiting the present disclosure. Where specific techniques or conditions are not specified in the embodiments, the techniques or conditions described in the literature in the art or in the product specifications shall be followed.

[0021] The present disclosure will be further illustrated below with reference to Figures 1 and 2 and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present disclosure and are not used to limit the scope of the present disclosure.

[0022] Example 1: This example is a negative electrode lead paste formula for inhibiting hydrogen evolution and extending the cycle life of lead-acid batteries. The contents of the components are as follows: high-purity humic acid is 4‰ of the weight of lead powder, sodium lignin sulfonate is 2‰ of the weight of lead powder, precipitated or ultrafine barium sulfate is 9‰ of the weight of lead powder, carbon black (specific surface area 1000-1600m 2 / g) is 8‰ of the weight of lead powder, acetylene black (specific surface area 50~80m 2 / g) is 1.5‰ of the weight of the lead powder, graphite powder (particle size above 300 mesh) is 2‰ of the weight of the lead powder, modified graphene is 0.1‰ of the weight of the lead powder, zinc oxide is 0.3‰ of the weight of the lead powder, super strong polyester staple fiber (fineness 0.5D, length 3mm to 5mm) is 0.5‰ of the weight of the lead powder, 1000kg of lead powder, dilute sulfuric acid is 10% of the weight of the lead powder, and deionized water is 11% of the weight of the lead powder.

[0023] The modified graphene treatment steps are as follows: graphene (double layer, D50 <10 μm) and dimethylacetamide are weighed in proportion and added into a reaction vessel, and ultrasonicated at 50-60° C. for 5 h until the graphene is completely dispersed to obtain a graphene suspension.

[0024] Furthermore, a method for preparing a lead-carbon negative electrode lead paste formula for inhibiting hydrogen evolution and extending the cycle life of lead-acid batteries comprises the following steps:

[0025] 1) Disperse the formulated amount of sodium lignin sulfonate, high-purity humic acid, precipitated or ultrafine barium sulfate, zinc oxide, and super-strong polyester staple fiber (fineness 0.5D, length 3mm to 5mm) evenly in the lead powder when making the lead paste, and dry-stir for about 5 minutes to mix evenly.

[0026] 2) Add the carbon black (specific surface area 1000~1600m 2 / g), acetylene black (specific surface area 50~80m 2 / g), graphite powder (particle size above 300 mesh), and modified graphene suspension are evenly mixed to form a suspension.

[0027] 3) Deionized water containing about 11% of the weight of the lead powder and the prepared carbon material suspension were quickly added to the lead powder mixed in step 1) and stirred for about 10 minutes.

[0028] 4) 10% of the weight of lead powder with a density of 1.3-1.35 g / cm 3 Slowly add dilute sulfuric acid to the lead paste obtained in step 3) for 10 to 15 minutes, continue stirring for 8 to 12 minutes, and then lower the temperature to 55°C to measure the apparent density. The apparent density is controlled at 4.43 ± 0.1 g / cm 3 .

[0029] 5) The paste temperature is required to be controlled between 45 and 55°C to ensure that sufficient highly active substances are generated during the preparation of the lead paste. The oxidation degree of the lead powder is required to be 70% to 78%, the iron, manganese, copper, and chlorine contents are required to be less than 5ppm, and the bismuth content is required to be less than 35ppm; the iron content in dilute sulfuric acid is required to be less than 0.5ppm, and the chlorine content is low.

[0030] Example 2: A lead-carbon negative electrode lead paste formula for inhibiting hydrogen evolution and extending the cycle life of lead-acid batteries. The contents of the components are as follows: high-purity humic acid is 5.5‰ of the weight of the lead powder, sodium lignin sulfonate is 3.5‰ of the weight of the lead powder, precipitated or ultrafine barium sulfate is 12‰ of the weight of the lead powder, carbon black (specific surface area 1000-1600m 2 / g) is 10‰ of the weight of lead powder, acetylene black (specific surface area 50~80m 2 / g) is 3‰ of the weight of lead powder, graphite powder (particle size above 300 mesh) is 3‰ of the weight of lead powder, modified graphene is 0.5‰ of the weight of lead powder, zinc oxide is 0.5‰ of the weight of lead powder, super strong polyester staple fiber (fineness 0.5D, length 3mm to 5mm) is 1.0‰ of the weight of lead powder, 1000kg of lead powder, dilute sulfuric acid is 12% of the weight of lead powder, and deionized water is 13% of the weight of lead powder.

[0031] The modified graphene treatment steps are as follows: graphene (double layer, D50 <10 μm) and dimethylacetamide are weighed in proportion and added into a reaction vessel, and ultrasonicated at 50-60° C. for 5 h until the graphene is completely dispersed to obtain a graphene suspension.

[0032] Furthermore, a method for preparing a negative electrode lead paste formula for inhibiting hydrogen evolution and extending the cycle life of lead-acid batteries comprises the following steps:

[0033] 1) Disperse the formulated amount of sodium lignin sulfonate, high-purity humic acid, precipitated or ultrafine barium sulfate, zinc oxide, and super-strong polyester staple fiber (fineness 0.5D, length 3mm to 5mm) evenly in the lead powder when making the lead paste, and dry-stir for about 5 minutes to mix evenly.

[0034] 2) Add the carbon black (specific surface area 1000~1600m 2 / g), acetylene black (specific surface area 50~80m 2 / g), graphite powder (particle size above 300 mesh), and modified graphene suspension are evenly mixed to form a suspension.

[0035] 3) Deionized water containing about 13% of the weight of the lead powder and the prepared carbon material suspension were quickly added to the lead powder mixed in step 1) and stirred for about 10 minutes.

[0036] 4) 12% of the weight of lead powder with a density of 1.3-1.35 g / cm 3 Slowly add dilute sulfuric acid to the lead paste obtained in step 3) for 10 to 15 minutes, continue stirring for 8 to 12 minutes, and then drop the temperature to 55°C to measure the apparent density. The apparent density is controlled at 4.45 ± 0.1 g / cm 3 .

[0037] 5) The paste temperature is required to be controlled between 45 and 55°C to ensure that sufficient highly active substances are generated during the preparation of the lead paste. The oxidation degree of the lead powder is required to be 70% to 78%, the iron, manganese, copper, and chlorine contents are required to be less than 5ppm, and the bismuth content is required to be less than 35ppm; the iron content in dilute sulfuric acid is required to be less than 0.5ppm, and the chlorine content is low.

[0038] The water loss test method in Figure 1 is:

[0039] 1. After the battery is fully charged, wipe the entire surface of the battery, dry it and weigh it to within ±0.05%;

[0040] 2. Then the battery is charged at a constant voltage for 500 hours at an ambient temperature of 40℃±3℃;

[0041] 3. After the battery is charged, immediately weigh the battery as required in step 1, calculate the mass loss due to the reduction of electrolyte, and convert it into g / Ah.

[0042] It should be noted that the above content merely illustrates the technical idea of ​​the present disclosure and cannot be used to limit the protection scope of the present disclosure. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present disclosure. These improvements and modifications all fall within the protection scope of the claims of the present disclosure.

Claims

1. A negative electrode lead paste for inhibiting hydrogen evolution and extending the cycle life of a battery, characterized in that: The negative electrode lead paste includes the following components: high-purity humic acid, sodium lignin sulfonate, precipitated or ultrafine barium sulfate, carbon black, acetylene black, graphite powder, modified graphene, zinc oxide, super strong polyester staple fiber, lead powder, dilute sulfuric acid and deionized water.

2. The negative electrode lead paste for inhibiting hydrogen evolution and extending the battery cycle life according to claim 1, characterized in that: The high-purity humic acid is 3.0-5.5‰ of the weight of the lead powder, the sodium lignin sulfonate is 2-3.5‰ of the weight of the lead powder, the precipitated or ultrafine barium sulfate is 8-12‰ of the weight of the lead powder, the carbon black is 7-10‰ of the weight of the lead powder, the acetylene black is 1.5-3‰ of the weight of the lead powder, the graphite powder is 1.5-3‰ of the weight of the lead powder, the modified graphene is 0.1-0.5‰ of the weight of the lead powder, the zinc oxide is 0.2-0.5‰ of the weight of the lead powder, the super strong polyester staple fiber is 0.5-1.0‰ of the weight of the lead powder, the lead powder is 1000kg, the dilute sulfuric acid is 9-12% of the weight of the lead powder, and the deionized water is 11-13% of the weight of the lead powder.

3. The negative electrode lead paste for inhibiting hydrogen evolution and extending the battery cycle life according to claim 1, characterized in that: The specific surface area of ​​carbon black is 1000~1600m 2 / g.

4. The negative electrode lead paste for inhibiting hydrogen evolution and extending the battery cycle life according to claim 1, characterized in that: The specific surface area of ​​acetylene black is 50~80m 2 / g.

5. The negative electrode lead paste for inhibiting hydrogen evolution and extending battery cycle life according to claim 1, characterized in that: The graphite powder has a particle size of 300 mesh or more.

6. The negative electrode lead paste for inhibiting hydrogen evolution and extending the battery cycle life according to claim 1, characterized in that: The fineness of the super-strong polyester staple fiber is 0.5D, and the length of the super-strong polyester staple fiber is 2mm to 4mm.

7. The negative electrode lead paste for inhibiting hydrogen evolution and extending the battery cycle life according to claim 1, characterized in that: The preparation steps of the modified graphene include: weighing double-layer graphene and graphene with D50<10 μm and dimethylacetamide in proportion, adding them into a reaction container, ultrasonicating at 50-60° C. for 5 hours until the graphene is completely dispersed, and obtaining a modified graphene suspension.

8. A method for preparing the negative electrode lead paste for inhibiting hydrogen evolution and extending the battery cycle life according to any one of claims 1 to 7, characterized in that: The method comprises the following steps: 1) Evenly disperse the formulated amount of sodium lignin sulfonate, high-purity humic acid, precipitated or ultra-fine barium sulfate, zinc oxide, and super-strong polyester staple fiber in the lead powder when making lead paste, and dry-stir for about 5 minutes to mix evenly; 2) Evenly mix the formulated carbon black, acetylene black, graphite powder and modified graphene suspension to prepare a suspension; 3) Deionized water with a weight of about 11-13% of the lead powder and the prepared carbon material suspension are quickly added to the lead powder mixed in step 1) and stirred for about 10 minutes; 4) 9-12% of the weight of lead powder with a density of 1.3-1.35 g / cm 3 Slowly add dilute sulfuric acid to the lead paste obtained in step 3) for 10 to 15 minutes, continue stirring for 8 to 12 minutes, and then drop the temperature to 55°C to measure the apparent density, which is controlled at 4.45 ± 0.1 g / cm 3 .

9. The method for preparing a negative electrode lead paste for inhibiting hydrogen evolution and extending the cycle life of a battery according to claim 8, characterized in that: During the preparation step, the temperature of the paste is controlled between 45 and 55°C.

10. The method for preparing a negative electrode lead paste for inhibiting hydrogen evolution and extending the cycle life of a battery according to claim 8, characterized in that: In the preparation step, the oxidation degree of the lead powder is 70% to 78%.

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