CN116111204A - Colloid lead-carbon battery and preparation thereof - Google Patents

Abstract

The invention provides a negative plate of a colloid lead-carbon battery, which is prepared by doping a certain amount of fumed silica into a negative active material of the lead-carbon battery. The negative electrode active material is: 500-800 parts of lead powder, 1-20 parts of carbon material, 6-10 parts of barium sulfate, 0.1-0.5 part of polypropylene short fiber with the length of 0.1-5mm and the diameter of 100nm-5 mu m and 0.0001-20 parts of fumed silica (preferably 0.001-1 part) in parts by weight; the positive electrode active material is: 500-800 parts of lead powder, 6-10 parts of barium sulfate and 0.1-0.5 part of polypropylene short fiber with the length of 0.1-5mm and the diameter of 100nm-5 mu m; the colloid electrolyte is sulfuric acid solution with the mass fraction of silicon dioxide of 0.01% -20%, preferably 0.5% -5%. After the battery is filled with the gel, part of the sulfuric acid solution in the sol permeates into the anode active material and reacts with the fumed silica sol to form silica gel in the electrode active material.

Description

Colloid lead-carbon battery and preparation thereof

Technical Field

The invention relates to the field of lead-carbon batteries, in particular to a colloid lead-carbon battery cathode.

Background

When lead-acid batteries are used for storage of electric energy produced by Hybrid Electric Vehicles (HEVs) or renewable energy sources, it is desirable to operate in a partial state of charge (PSoC) or a high rate partial state of charge (HRPSoC). At this time, pbSO may occur ₄ Is a recrystallization process leading to fine PbSO ₄ Crystal dissolution, low solubility PbSO ₄ The crystal continues to growAnd gradually accumulates on the surface of the anode. Coarse PbSO on the electrode surface when the battery is charged ₄ The crystals are not efficiently converted to Pb, i.e. irreversible sulfation occurs. The lead-acid battery is recycled under the working condition of PSoC or HRPSC, and along with the increase of the cycle times, the lead-acid battery has large PbSO ₄ The crystals further grow, eventually leading to gradual sulfation of the anode active material. Unreduced PbSO ₄ Will deposit to the surface of the sponge Pb, limiting the contribution of Pb to the charging process. Thus, the charge acceptance and charge efficiency of the negative electrode of a lead-acid battery will be greatly reduced, eventually leading to failure of the battery.

In order to solve the problem of irreversible sulfation of the negative electrode of a lead-acid battery and improve the electrochemical performance of the battery, a great deal of research has been made in recent years. One of the main approaches is to add a carbon material such as graphite, carbon Black (CB), activated Carbon (AC), carbon Nanotubes (CNT) or a mixture thereof to a battery anode active material to construct a lead-carbon battery. Different types of carbon material additives have different effects on the negative electrode of the lead-carbon battery. For example, logeshkumar et al studied the effect of some nanostructure additives on the performance of the negative electrode (S.Logeshkumar, R.Manoharan, influence of some nanostructured materials additives on the performance of lead acid battery negative electrodes, electrochromic Acta,144 (2014): 147-153). The charge and discharge tests show that the performance of the battery is improved to different degrees by doping different kinds of carbon materials compared with the battery without using the additive. The addition of the multi-wall carbon nano tube can lead the battery to obtain the maximum specific capacity improvement. In the negative electrode of the lead-carbon battery, different kinds of carbon materials play different roles, including conductive network construction, double-layer capacitance effect, porous structure formation and steric hindrance effect. Although the sulfation process of the negative electrode is inhibited by doping a higher proportion of carbon material into the negative electrode, and the cycle life of the battery is prolonged under the working condition of PSoC or HRPSC, the reason for the final failure of the lead-carbon battery is still sulfation of the negative electrode, especially serious sulfation of the lower part of the negative electrode. The main reason for serious sulfation of the lower part of the negative electrode is the layering of the electrolyte, i.e. H in the electrolyte under the action of gravity ₂ SO ₄ Gradually deposit toward the bottom of the cell, causing the cell toThe lower electrolyte concentration is much higher than the electrolyte in the upper part of the cell. Electrolyte stratification can lead to capacity degradation. In addition, the grid corrosion rate and the active material irreversible sulfation rate of the lower region of the plate (i.e., the region where the acid concentration is higher than normal) may increase, resulting in accelerated battery failure.

Since the advent of gel lead-acid batteries, much work has been done in terms of battery structural design, performance characteristics, and durability, but little research has been done on gel lead-carbon batteries. It is generally believed that the electrolyte layering degree of a gel valve-regulated sealed lead acid battery is lighter than that of a valve-regulated sealed glass fiber membrane (AGM) lead acid battery, especially in deep discharge cycle applications such as Remote Area Power Supply (RAPS) applications. Since acid stratification is also present in lead-carbon batteries, it is necessary to introduce a colloidal electrolyte into the lead-carbon batteries to construct the colloidal lead-carbon batteries to further improve the cycle life of the lead-carbon batteries. For the colloid lead-carbon battery, although the sol can enter the separator and the gap between the separator and the electrode plate in the process of filling the colloid, the sol is difficult to permeate into the electrode active material. That is, in the electrode active material, the electrolyte is present in the form of a solution. The liquid electrolyte also has layering phenomenon in the electrode active material, so that the acid concentration in the electrode active material at the lower part is higher than that in the electrode active material at the upper part, and along with the charge and discharge cycle, the active material at the lower part of the negative plate can be subjected to serious sulfation, so that the battery capacity is continuously reduced, and finally the battery is disabled.

Disclosure of Invention

The technical problem to be solved by the invention (the purpose of the invention) is:

the invention provides a negative plate of a colloid lead-carbon battery, which is prepared by doping a certain amount of fumed silica into a negative active material of the lead-carbon battery. After the battery is filled with the gel, part of the sulfuric acid solution in the sol permeates into the anode active material and reacts with the fumed silica sol to form silica gel in the electrode active material.

A colloid lead-carbon battery comprises a negative electrode, a positive electrode and electrolyte,

the negative electrode active material is: 500-800 parts of lead powder, 1-20 parts of carbon material, 6-10 parts of barium sulfate, 0.1-0.5 part of polypropylene short fiber with the length of 0.1-5mm and the diameter of 100nm-5 mu m and 0.0001-20 parts of silicon dioxide (preferably 0.001-10 parts) in parts by weight;

the positive electrode active material is: 500-800 parts of lead powder, 6-10 parts of barium sulfate and 0.1-0.5 part of polypropylene short fiber with the length of 0.1-5mm and the diameter of 100nm-5 mu m;

the electrolyte is colloid electrolyte which is sulfuric acid solution with the mass fraction of silicon dioxide of 0.01% -20%, preferably 0.5% -5%.

The silica material has an average particle diameter of 0.1nm to 5. Mu.m, preferably 500nm to 2. Mu.m.

The sulfuric acid solution comprises the following components in percentage by mass: 1.1g/ml-1.4g/ml.

The preparation method comprises the following steps:

A. preparation of the negative electrode: (1) According to the weight portion, 500-800 portions of lead powder, 1-20 portions of carbon material, 6-10 portions of barium sulfate, 0.1-0.5 portion of polypropylene short fiber with the length of 0.1-5mm and the diameter of 100nm-5 mu m, and 0.0001-20 portions of silicon dioxide are stirred and premixed (the addition amount of the silicon dioxide is preferably 0.001-1 portion), 50-100 portions of deionized water is added into the premixed powder material while stirring, and the stirring is continued for 1-60 minutes to obtain lead plaster;

(2) Scraping lead plaster on the metal lead grid, filling the through holes on the metal lead grid with the lead plaster, and solidifying and drying to obtain the negative electrode of the lead-carbon battery; the curing temperature is 30-50 ℃, the humidity is 70-95%, and the curing time is 10-30 hours; the drying temperature is 60-120 ℃ and the drying time is 10-30 hours;

B. preparation of positive electrode: preparing a positive electrode of the lead-acid battery according to the same process steps and conditions as those of the step (1) and the step (2) in the preparation of the negative electrode A, wherein the positive electrode material is not added with any carbon material and any silicon dioxide material;

C. the lead-carbon battery is assembled, and the electrolyte added into the lead-carbon battery is sulfuric acid solution, and the mass concentration of the electrolyte is as follows: 1.1g/ml to 1.4g/ml, and the mass ratio of the sulfuric acid electrolyte to the total mass of the active materials of the negative electrode except the metal lead plate grid is 60 to 120:50, preferably 60-100:50.

5. the method of manufacturing according to claim 4, wherein: the size of the metal lead grid is 50-1000mm long, 20-80mm wide and 0.5-4mm thick.

The invention has the beneficial effects that

The electrolyte in the electrode active material exists in a gel form, so that acid layering can be avoided, the sulfation process of the active material at the lower part of the negative electrode is delayed, and the charge-discharge cycle life of the lead-carbon battery is further prolonged. In addition, the existence of the colloid electrolyte in the electrode active material can reduce the adsorption of the carbon material to organic additives such as lignin and the like, and improve the low-temperature performance of the lead-carbon battery.

Detailed Description

Example 1

The lead-carbon battery is prepared by the following steps:

1. preparation of the negative electrode: (1) Premixing 600g of lead powder, 9g of activated carbon, 8.4g of barium sulfate, 0.3g of polypropylene short fiber with the length of 5mm and the diameter of 0.5-1.5 mu m and 2g of fumed silica with the average particle size of 1 mu m by a high-speed stirrer, adding 84g of deionized water into the premixed powder while stirring, and continuously stirring for 10min to obtain lead plaster; (2) And (3) scraping the lead plaster on a metal lead grid, wherein the size of the grid is 70mm long and 50mm wide and 2mm thick, and solidifying and drying to obtain the negative electrode of the lead-carbon battery. Curing temperature is 40 ℃, humidity is 80 percent, and curing time is 20 hours; the drying temperature is 80 ℃ and the drying time is 24 hours;

2. preparation of positive electrode: preparing a positive electrode of the lead-acid battery according to the same process steps as the negative electrode preparation step (1) and the step (2), except that the positive electrode is not added with any carbon material and fumed silica material;

3. and (3) preparing a lead-carbon battery: and sequentially and alternately arranging three positive plates and two negative plates in parallel at intervals, arranging PE (polyethylene) diaphragms of a commercial lead-acid battery between the positive plates and the negative plates, and respectively welding the two negative plates in parallel and the three positive plates in parallel, wherein the total mass of positive active substances (the total mass of the lead paste on the three positive plates after drying) of the lead-acid battery is 20.0g, the total mass of the positive active substances refers to the total mass of the lead paste contained in the three positive plates after welding in parallel, the total mass of negative active substances (the total mass of the lead paste on the two negative plates after drying) is 14.3g, and the total mass of the negative active substances refers to the total mass of the lead paste contained in the two negative plates after welding in parallel. The positive and negative electrode grids adopt conventional lead grids, and the size is 70mm long and 50mm wide and 2mm thick; the positive and negative electrodes were placed in a tightly assembled battery case, wherein the battery case was 76mm long, 40mm wide and 100mm high, and 83g of a sulfuric acid solution containing 1% by mass of silica and having a density of 1.275g/ml was injected into the battery case;

and (3) carrying out normal temperature service life test on the battery: adopting 4.2A constant current discharge for 59 seconds, 18A discharge for 1 second, adopting 6.3A current for 2.3V voltage constant current constant voltage charge for 60 seconds, circulating the charge and discharge conditions 3600 times, then standing for 40 hours, restarting the circulation after 40 hours, and reducing the battery voltage to below 1.2V as the end condition of life test;

the initial voltage of the assembled internal mixed battery is 2.1742V in the normal-temperature full-charge state, and the internal mixed battery can run 18197 circles in the normal-temperature life test. Compared with the test result of the common lead-acid battery with the same lead element content under the same test condition (7223 circles), the normal-temperature cycle life of the internal mixed lead-acid carbon battery can reach 2.5 times of the service life of the conventional lead-acid battery.

Example 2

The procedure was as in example 1, except that the lead-carbon battery was modified to have an addition amount of fumed silica of 4g as required in example 1 without changing other conditions. The assembled internal mixed battery can run 18129 circles in a normal temperature life test. Compared with the test result of the common lead-acid battery with the same lead element content under the same test condition (7223 circles), the normal-temperature cycle life of the internal mixed lead-acid carbon battery can reach 2.5 times of the service life of the conventional lead-acid battery.

Example 3

The procedure was as in example 1, except that the lead-carbon battery was modified according to the requirements of example 1, without changing other conditions, and fumed silica having an average particle diameter of 4 μm was used as an additive in the same mass. The assembled internal mixed battery can run 18418 circles in a normal temperature life test. Compared with the test result of the common lead-acid battery with the same lead element content under the same test condition (7223 circles), the normal-temperature cycle life of the internal mixed lead-acid carbon battery can reach 2.5 times of the service life of the conventional lead-acid battery.

Example 4

The procedure is as in example 1, except that the lead-carbon battery is changed from a sulfuric acid electrolyte having a density of 1.275g/ml and containing 1% by mass of silica to 110g in accordance with the requirements of example 1 without changing other conditions. The assembled internal mixed battery can run 18563 circles in a normal temperature life test. Compared with the test result of the common lead-acid battery with the same lead element content under the same test condition (7223 circles), the normal-temperature cycle life of the internal mixed lead-acid carbon battery can reach 2.5 times of the service life of the conventional lead-acid battery.

Comparative example 1

The procedure was as in example 1, except that the lead-acid battery was prepared without changing other conditions, without adding any silica material, without adding any carbon material, according to the requirements of example 1. The battery can run for 7223 circles under normal temperature.

Comparative example 2

The procedure was the same as in example 1, except that the lead-carbon battery was subjected to the life test 4325 cycles at normal temperature, as the large-sized silica increased the internal resistance of the electrode seriously, without changing other conditions, by adding a silica material having a particle diameter of 10 μm according to the requirements of example 1.

Comparative example 3

The procedure was as in example 1, except that the lead-carbon battery was operated for 1842 cycles at normal temperature, as the addition of a large amount of silica severely increased the internal resistance of the electrode, without changing other conditions, changing the addition amount of fumed silica to 60g, as required in example 1.

Comparative example 4

The process is the same as in example 1, except that the lead-carbon battery is prepared by using fumed silica with average particle diameter of less than 10 μm according to the requirement of example 1 without changing other conditions, and the internal resistance of the electrode is increased due to the overlarge particle diameter of the silica particles, so that the battery can run for 1842 circles under normal temperature conditions.

Comparative example 5

The process is the same as in example 1, and is different from that of example 1 in that the lead-carbon battery is characterized in that according to the requirements of example 1, other conditions are not changed, the mass of the added electrolyte is changed to 200g, and the excessive addition of the electrolyte seriously aggravates the amount of lead ions generated into lead sulfate in chemical reaction, so that the increase of the internal resistance of the electrode is too fast, and the battery can run for 1842 circles under normal temperature conditions. Comparative example 6

The procedure was as in example 1, except that according to the requirements of example 1, silica particles were not mixed in the electrode preparation process, but the same mass of the same particle diameter silica particles were sufficiently dispersed in the sulfuric acid electrolyte added in advance, and a colloidal electrolyte was prepared in advance and injected into the lead-carbon battery. Because the gel electrolyte is formed too fast, the coagulation condition of the gel block is serious, the uniform distribution of the electrolyte is affected, the sulfation problem is caused to occur rapidly in the local area of the electrode, the increase of the internal resistance of the electrode is too fast, and the battery can run for 3221 circle under the normal temperature condition.

The electrolyte in the electrode active material exists in a gel form, so that acid layering can be avoided, the sulfation process of the active material at the lower part of the negative electrode is delayed, and the charge-discharge cycle life of the lead-carbon battery is further prolonged.

Claims (5)

1. The utility model provides a colloid lead carbon battery, includes negative pole, positive pole and electrolyte, its characterized in that:

the negative electrode active material is: 500-800 parts by weight of lead powder, 1-20 parts by weight of carbon material, 6-10 parts by weight of barium sulfate, 0.1-0.5 part by weight of polypropylene short fiber with the length of 0.1-5mm and the diameter of 100nm-5 mu m, and 0.0001-20 parts by weight of silicon dioxide (preferably 0.001-10 parts by weight);

the positive electrode active material is: 500-800 parts of lead powder, 6-10 parts of barium sulfate and 0.1-0.5 part of polypropylene short fiber with the length of 0.1-5mm and the diameter of 100nm-5 mu m;

the electrolyte is colloid electrolyte which is sulfuric acid solution with the mass fraction of silicon dioxide of 0.01% -20%, preferably 0.5% -5%.

2. The gel lead carbon battery of claim 1, wherein:

the silica material has an average particle diameter of 0.1nm to 5. Mu.m, preferably 500nm to 2. Mu.m.

3. The gel lead carbon battery of claim 1, wherein:

the sulfuric acid solution comprises the following components in percentage by mass: 1.1g/ml-1.4g/ml.

4. A method for preparing the colloidal lead-carbon battery according to any one of claims 1 to 3, which is characterized in that:

A. preparation of the negative electrode: (1) According to the weight portion, 500-800 portions of lead powder, 1-20 portions of carbon material, 6-10 portions of barium sulfate, 0.1-0.5 portion of polypropylene short fiber with the length of 0.1-5mm and the diameter of 100nm-5 mu m, and 0.0001-20 portions of silicon dioxide are stirred and premixed (the addition amount of the silicon dioxide is preferably 0.001-1 portion), 50-100 portions of deionized water is added into the premixed powder material while stirring, and the stirring is continued for 1-60 minutes to obtain lead plaster;

(2) Scraping lead plaster on the metal lead grid, filling the through holes on the metal lead grid with the lead plaster, and solidifying and drying to obtain the negative electrode of the lead-carbon battery; the curing temperature is 30-50 ℃, the humidity is 70-95%, and the curing time is 10-30 hours; the drying temperature is 60-120 ℃ and the drying time is 10-30 hours;

B. preparation of positive electrode: preparing a positive electrode of the lead-acid battery according to the same process steps and conditions as those of the step (1) and the step (2) in the preparation of the negative electrode A, wherein the positive electrode material is not added with any carbon material and any silicon dioxide material;

C. the lead-carbon battery is assembled, and the electrolyte added into the lead-carbon battery is sulfuric acid solution, and the mass concentration of the electrolyte is as follows: 1.1g/ml to 1.4g/ml, and the mass ratio of the sulfuric acid electrolyte to the total mass of the active materials of the negative electrode except the metal lead plate grid is 60 to 120:50, preferably 60-100:50.

5. the method of manufacturing according to claim 4, wherein: the size of the metal lead grid is 50-1000mm long, 20-80mm wide and 0.5-4mm thick.