Lead-sodium battery negative electrode lead paste and preparation method thereof

Abstract

The invention discloses a lead paste for a negative electrode of a lead-sodium battery in the technical field of storage batteries. The lead paste comprises the following materials in parts by weight: 100 parts of lead oxide powder, 6-12 parts of sulfuric acid, 11-20 parts of deionized water; 0.05-0.07 parts of short fibers, 0.3-0.9 parts of humic acid, 0.1-0.3 parts of sodium lignin sulfonate, 0.06-1 parts of silicon dioxide, 0.8-1.6 parts of barium sulfate, 0.1-0.5 parts of sodium sulfate, 0.04-0.1 parts of ammonium persulfate, 0.06-0.1 parts of vanillin, 0.2-0.4 parts of glue, and 0.2-0.4 parts of a mixed carbon material. The lead paste effectively improves the stability of the additives and the uniformity of mixing, thereby increasing the low-temperature resistance and service life of the battery.

Description

Technical Field

[0001] The present invention relates to the technical field of storage batteries, in particular to a lead-sodium storage battery. Background Art

[0002] Traditional negative electrode lead paste is prepared by mixing lead oxide powder, sulfuric acid, deionized water, short fibers, and additives in a paste mixer in a specific proportion using dry, water, and acid mixing. Negative electrode additives enhance charge acceptance, extend battery life, improve low-temperature discharge performance, and inhibit sulfation. However, the uniformity of the additives in the paste affects its performance. While organic expanders such as sodium ligninsulfonate can improve low-temperature performance and modify the morphology of lead sulfate crystals, sodium ligninsulfonate exhibits poor stability after addition to the negative electrode, dissolving during charge and discharge, gradually diminishing its effectiveness. These issues contribute to poor low-temperature performance and a short battery life. Therefore, a negative electrode lead paste for lead-sodium batteries and a preparation method are needed to address these issues. Summary of the Invention

[0003] In response to the deficiencies in the prior art, the present invention provides a lead paste for the negative electrode of a lead-sodium battery, which can effectively improve the low-temperature resistance and life of the battery.

[0004] The object of the present invention is achieved as follows: A lead paste for negative electrode of a lead-sodium battery comprises the following materials in parts by weight:

[0005] 100 parts of lead oxide powder, 6-12 parts of sulfuric acid, 11-20 parts of deionized water; 0.05-0.07 parts of short fibers, 0.3-0.9 parts of humic acid, 0.1-0.3 parts of sodium lignin sulfonate, 0.06-1 parts of silicon dioxide, 0.8-1.6 parts of barium sulfate, 0.1-0.5 parts of sodium sulfate, 0.04-0.1 parts of ammonium persulfate, 0.06-0.1 parts of vanillin, 0.2-0.4 parts of glue, and 0.2-0.4 parts of mixed carbon materials.

[0006] Furthermore, the lead oxide powder has an oxidation degree of 72-80% and a particle size of ≤5 μm.

[0007] Furthermore, the silica particles have a particle size of ≤30 μm.

[0008] Furthermore, the carbon material includes acetylene black, carbon black, and graphene.

[0009] A method for preparing negative electrode lead paste for a lead-sodium battery comprises the following steps:

[0010] S1. Add humic acid, lignin or sodium lignin sulfonate to deionized water according to the proportion and stir to dissolve. Add silicon dioxide particles in a set proportion to the prepared solution, then reduce and increase the pressure, mix thoroughly and dry to obtain a mixture A.

[0011] S2. Add mixture A and barium sulfate and sodium sulfate in proportion to a ball mill and mix them to obtain mixture B;

[0012] S3. Add the adhesive to deionized water and dissolve it in a certain proportion to prepare an adhesive solution;

[0013] S4. Add mixture B, short fibers, ammonium persulfate, vanillin, and mixed carbon materials into a paste mixer and dry mix with lead powder. Then, add the glue solution and the remaining deionized water and sulfuric acid respectively for water mixing and acid mixing to prepare a negative electrode lead paste.

[0014] Furthermore, the stirring time of the stirring and dissolving in S1 is greater than 10 minutes. After adding a set proportion of silicon dioxide particles to the prepared solution, the pressure is reduced to -0.1~-0.3MPa, and then increased to 0.1MPa. After thorough mixing, the solution is dried at a temperature of ≥60°C and a time of >5h.

[0015] Furthermore, the ball mill speed in S2 is 200-300 rpm, and the mixing time is 0.5-1 h.

[0016] Furthermore, the dry mixing time in S4 is 5-12 minutes, and the deionized water and sulfuric acid are mixed with water and acid respectively, the water adding time is 1-3 minutes, and the water mixing time is 5-10 minutes. The density of the sulfuric acid is 1.4 g / cm 3 , acid adding time is 15~20min, and acid mixing time is 5~10min.

[0017] Compared with the prior art, the beneficial effects of the present invention are: the present invention can effectively improve the stability of additives and the uniformity of mixing, wherein mixture A has a more stable structure, humic acid and sodium lignin sulfonate are immersed in silica particles by increasing and decreasing pressure, thereby solving the instability problem of sodium lignin sulfonate, and during battery charging and discharging, the sodium lignin sulfonate in mixture A is not easily dissolved, and at the same time, under the action of humic acid and silica, it has better low-temperature performance, and also has an excellent effect on inhibiting hydrogen evolution at the negative electrode; the mixed carbon material can construct a higher conductive network, improve the conductivity and the activity of ion migration under low temperature conditions; further, mixture A is added to a ball mill with barium sulfate and sodium sulfate for mixing to obtain mixture B, achieving physical intercalation, and the powder particle size is uniform, ensuring that the mixture and paste after grinding can be evenly distributed in the active material, so that the performance of each mixed component material in the battery is fully exerted, and under the joint action of other additives such as ammonium persulfate, vanillin, and glue, the stability, low temperature resistance and service life of the battery are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0019] Figure 1 Schematic diagram of the discharge of a battery under low temperature conditions applied to an embodiment of the present invention and a comparative example.

[0020] Figure 2 Schematic diagram of discharge of a battery under normal temperature conditions applied to an embodiment of the present invention and a comparative example.

[0021] Figure 3 The graph is a cycle life curve of a battery when the embodiment of the present invention and the comparative example are applied. DETAILED DESCRIPTION

[0022] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0023] Example 1

[0024] A lead paste for a negative electrode of a lead-sodium battery comprises the following materials in parts by weight: 100 parts of lead oxide powder, 6 parts of sulfuric acid, 11 parts of deionized water, 0.05 parts of short fibers, 0.3 parts of humic acid, 0.1 parts of sodium lignin sulfonate, 0.06 parts of silicon dioxide, 0.8 parts of barium sulfate, 0.1 parts of sodium sulfate, 0.04 parts of ammonium persulfate, 0.06 parts of vanillin, 0.2 parts of glue, and 0.2 parts of a mixed carbon material.

[0025] Specifically, the lead powder has an oxidation degree of 72%, a particle size of 3-4 μm, silicon dioxide particles ≤ 30 μm, and the carbon material is 0.1 part of acetylene black, 0.05 part of carbon black, and 0.05 part of graphene.

[0026] A method for preparing negative electrode lead paste for a lead-sodium battery comprises the following steps:

[0027] S1. According to the proportion, 0.3 parts of humic acid and 0.1 parts of sodium lignin sulfonate were added to 1 part of deionized water and stirred for 20 minutes. 0.06 parts of silicon dioxide particles were added to the prepared solution, and the pressure was reduced to -0.1 MPa for 30 minutes, and then increased to 0.1 MPa. After thorough mixing, the mixture was dried at 90°C for 24 hours to obtain a mixture A.

[0028] S2. Add mixture A, 0.8 parts of barium sulfate and 0.1 parts of sodium sulfate in proportion into a ball mill and mix them at a speed of 300 rpm for 0.5 h.

[0029] S3, dissolving 0.2 parts of adhesive in 0.8 parts of deionized water to prepare an adhesive solution;

[0030] S4. Add mixture B, 0.05 parts of short fibers, 0.04 parts of ammonium persulfate, 0.06 parts of vanillin, 0.1 parts of acetylene black, 0.05 parts of carbon black, and 0.05 parts of graphene into a paste mixer and dry mix with lead powder for 8 minutes. Then, add 1 part of the glue solution and the remaining 9 parts of deionized water and 6 parts of sulfuric acid respectively for water mixing and acid mixing. The water adding time is 1.5 minutes, the water mixing time is 6 minutes, the density of sulfuric acid is 1.4 g / cm3, the acid adding time is 17 minutes, and the acid mixing time is 5 minutes, thereby preparing the negative electrode lead paste.

[0031] Example 2

[0032] A lead paste for a negative electrode of a lead-sodium battery comprises the following materials in parts by weight: 100 parts of lead oxide powder, 9 parts of sulfuric acid, 15 parts of deionized water, 0.06 parts of short fibers, 0.6 parts of humic acid, 0.2 parts of sodium lignin sulfonate, 0.08 parts of silicon dioxide, 1.2 parts of barium sulfate, 0.3 parts of sodium sulfate, 0.07 parts of ammonium persulfate, 0.08 parts of vanillin, 0.3 parts of glue, and 0.3 parts of a mixed carbon material.

[0033] Specifically, the lead powder has an oxidation degree of 74%, a particle size of 4-5 μm, silicon dioxide particles ≤ 30 μm, and the carbon material is 0.2 parts of acetylene black, 0.05 parts of carbon black, and 0.05 parts of graphene.

[0034] A method for preparing negative electrode lead paste for a lead-sodium battery comprises the following steps:

[0035] S1. According to the proportion, 0.6 parts of humic acid and 0.2 parts of sodium lignin sulfonate were added to 2 parts of deionized water and stirred to dissolve for 20 minutes. 0.08 parts of silicon dioxide particles were added to the prepared solution, and the pressure was reduced to -0.1 MPa for 45 minutes, and then increased to 0.1 MPa. After thorough mixing, the mixture was dried at 75°C for 36 hours to obtain a mixture A.

[0036] S2. Add mixture A, 1.2 parts of barium sulfate and 0.3 parts of sodium sulfate in proportion into a ball mill and grind them at a speed of 200 rpm for 1 hour.

[0037] S3, dissolving 0.3 parts of adhesive in 1.2 parts of deionized water to prepare an adhesive solution;

[0038] S4. Add mixture B, 0.06 parts of short fibers, 0.07 parts of ammonium persulfate, 0.08 parts of vanillin, 0.2 parts of acetylene black, 0.05 parts of carbon black, and 0.05 parts of graphene into a paste mixer and dry mix with lead powder for 6 minutes. Then, add 1.5 parts of the glue solution and the remaining 11.8 parts of deionized water and 9 parts of sulfuric acid respectively for water mixing and acid mixing. The water adding time is 1 minute, the water mixing time is 6 minutes, the density of sulfuric acid is 1.4 g / cm3, the acid adding time is 16 minutes, and the acid mixing time is 6 minutes, thereby preparing a negative electrode lead paste.

[0039] Example 3

[0040] A lead paste for a negative electrode of a lead-sodium battery comprises the following materials in parts by weight: 100 parts of lead oxide powder, 12 parts of sulfuric acid, 20 parts of deionized water; 0.07 parts of short fibers, 0.9 parts of humic acid, 0.3 parts of sodium lignin sulfonate, 1 part of silicon dioxide, 1.6 parts of barium sulfate, 0.5 parts of sodium sulfate, 0.1 parts of ammonium persulfate, 0.1 parts of vanillin, 0.4 parts of glue, and 0.4 parts of a mixed carbon material.

[0041] Specifically, the lead powder has an oxidation degree of 72%, a particle size of 3-4 μm, silicon dioxide particles ≤ 30 μm, and the carbon material is 0.2 parts of acetylene black, 0.15 parts of carbon black, and 0.05 parts of graphene.

[0042] A method for preparing negative electrode lead paste for a lead-sodium battery comprises the following steps:

[0043] S1. According to the proportion, 0.9 parts of humic acid and 0.3 parts of sodium lignin sulfonate were added to 3 parts of deionized water, stirred and dissolved for 15 minutes, 1 part of silicon dioxide particles was added to the prepared solution, and the pressure was reduced to -0.15 MPa for 20 minutes, and then increased to 0.1 MPa. After thorough mixing, the mixture was dried at 70°C for 40 hours to obtain a mixture A.

[0044] S2. Add mixture A, 1.6 parts of barium sulfate and 0.5 parts of sodium sulfate in proportion to each other into a ball mill and grind them at a speed of 250 rpm for 0.5 h.

[0045] S3, dissolving 0.4 parts of adhesive in 1.6 parts of deionized water to prepare an adhesive solution;

[0046] S4. Add mixture B, 0.07 parts of short fibers, 0.1 parts of ammonium persulfate, 0.1 parts of vanillin, 0.2 parts of acetylene black, 0.15 parts of carbon black, and 0.05 parts of graphene into a paste mixer and dry mix with lead powder for 10 minutes. Then, add 2 parts of the glue solution and the remaining 15.4 parts of deionized water and 12 parts of sulfuric acid respectively for water mixing and acid mixing. The water adding time is 1 minute, the water mixing time is 5 minutes, the density of sulfuric acid is 1.4 g / cm3, the acid adding time is 15 minutes, and the acid mixing time is 5 minutes, thereby preparing a negative electrode lead paste.

[0047] Comparative Example

[0048] A lead paste for a negative electrode of a lead-acid battery comprises the following materials in parts by weight: 100 parts of lead oxide powder, 9 parts of sulfuric acid, 12 parts of deionized water, 0.06 parts of short fibers, 0.6 parts of humic acid, 0.2 parts of sodium lignin sulfonate, 1.2 parts of barium sulfate, 0.2 parts of acetylene black, and 0.1 parts of carbon black.

[0049] A method for preparing negative electrode lead paste for a lead-acid battery comprises the following steps: adding 0.06 parts of short fibers, 0.6 parts of humic acid, 0.2 parts of sodium lignin sulfonate, 1.1 parts of barium sulfate, 0.2 parts of acetylene black, and 0.1 parts of carbon black into a paste mixer, dry-mixing the mixture with lead powder for 6 minutes, and mixing the mixture with 12 parts of deionized water and 9 parts of sulfuric acid, respectively, with water addition for 1 minute and water mixing for 6 minutes; the density of sulfuric acid is 1.4 g / cm3, acid addition for 16 minutes, and acid mixing for 6 minutes, thereby preparing the negative electrode lead paste.

[0050] The negative electrode lead pastes of Examples 1, 2, and 3 and the comparative example were made into negative electrode plates. It should be noted that the preparation process of the negative electrode plates is conventional and will not be described in detail in this scheme. With the plate ratio, separator, and battery shell being identical, the batteries were prepared by acidification. The following test methods were used:

[0051] 1. 10-hour rate capacity test: After the fully charged battery is charged for 1 hour to 24 hours, 10 (A) Current discharge, the battery ambient temperature is maintained between 20 ~ 25 ℃. The change in current value during the discharge time should not exceed 1%. When the battery cell voltage reaches 1.80V, stop discharging and record the discharge time to calculate the discharge capacity.

[0052] 2. -40℃ low temperature capacity test: Place the fully charged battery in a -40℃±2℃ environment for 20 hours. 10 (A) Discharge with a current. During the discharge process, the ambient temperature of the battery is maintained between -40°C ± 2°C, and the change in the current value should not exceed 1%. When the battery cell voltage reaches 1.80V, stop discharging and record the discharge time to calculate the discharge capacity.

[0053] 3. Cycle life test: The battery ambient temperature is kept between 20~25℃, a) I 10 (a) Discharge the battery until the cell voltage reaches 1.80V; b) Limit the voltage to 2.35V / cell and charge at 2.5I10(A) for 12 hours; c) Repeat steps a) and b). (The life test terminates when the discharge time in step a is less than 8 hours.)

[0054]

[0055] From the above, it can be seen that Figure 1-3 As shown, when comparing the solutions of Examples 1 to 3 with the comparative example, while the 10-hour rate capacity is similar, the lead paste and preparation method of the present invention can achieve better low-temperature performance and cycle life. The present invention has simple components and low production costs. The resulting battery has good low-temperature resistance and cycle life, and has a wide range of applications.

[0056] The above embodiments are only intended to help understand the method and core concept of the present invention. It should be noted that, without departing from the principles of the present invention, a number of improvements and modifications may be made to the present invention by those skilled in the art, and such improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A lead paste for negative electrode of a lead-sodium battery, characterized in that: The composition comprises the following materials in parts by weight: 100 parts of lead oxide powder, 6-12 parts of sulfuric acid, 11-20 parts of deionized water; 0.05-0.07 parts of short fibers, 0.3-0.9 parts of humic acid, 0.1-0.3 parts of sodium ligninsulfonate, 0.06-1 parts of silicon dioxide, 0.8-1.6 parts of barium sulfate, 0.1-0.5 parts of sodium sulfate, 0.04-0.1 parts of ammonium persulfate, 0.06-0.1 parts of vanillin, 0.2-0.4 parts of glue, and 0.2-0.4 parts of mixed carbon material; the humic acid and sodium ligninsulfonate are impregnated into silicon dioxide particles by increasing and decreasing the pressure.

2. The negative electrode lead paste for lead-sodium battery according to claim 1, characterized in that: The lead oxide powder has an oxidation degree of 72-80% and a particle size of ≤5 μm.

3. A lead paste for negative electrode of a lead-sodium battery according to claim 1 or 2, characterized in that: The silica particles have a particle size of ≤30 μm.

4. A lead paste for negative electrode of a lead-sodium battery according to claim 1 or 2, characterized in that: The carbon material includes acetylene black, carbon black and graphene.

5. A method for preparing a negative electrode lead paste for a lead-sodium battery according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1. Add humic acid and sodium lignin sulfonate to deionized water according to the proportion and stir to dissolve. Add silicon dioxide particles in a set proportion to the prepared solution, then reduce and increase the pressure. After thorough mixing, dry the mixture to obtain a mixture A. S2. Add mixture A and barium sulfate and sodium sulfate in proportion to a ball mill and mix them to obtain mixture B; S3. Add the adhesive to deionized water and dissolve it in a certain proportion to prepare an adhesive solution; S4. Add mixture B, short fibers, ammonium persulfate, vanillin, and mixed carbon materials into a paste mixer and dry mix with lead oxide powder. Then, add the glue solution and the remaining deionized water and sulfuric acid respectively for water mixing and acid mixing to prepare a negative electrode lead paste.

6. The method for preparing a negative electrode lead paste for a lead-sodium battery according to claim 5, wherein: The stirring time for the stirring and dissolving in S1 is greater than 10 minutes. After adding a set proportion of silicon dioxide particles to the prepared solution, the pressure is reduced to -0.1~-0.3MPa, and then increased to 0.1MPa. After thorough mixing, the solution is dried at a temperature of ≥60°C and a drying time of greater than 5 hours.

7. The method for preparing a negative electrode lead paste for a lead-sodium battery according to claim 5 or 6, characterized in that: The ball mill speed in S2 is 200~300rpm, and the mixing time is 0.5~1h.

8. The method for preparing a negative electrode lead paste for a lead-sodium battery according to claim 5 or 6, characterized in that: The dry mixing time in S4 is 5-12 minutes, and the adhesive solution and the remaining deionized water and sulfuric acid are mixed with water and acid respectively. The water adding time is 1-3 minutes, and the water mixing time is 5-10 minutes. The density of the sulfuric acid is 1.4 g / cm 3 , acid adding time is 15~20min, and acid mixing time is 5~10min.

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