CN111180805A - Waste lead-acid storage battery repairing activator and preparation method thereof - Google Patents

Abstract

The invention discloses a waste lead-acid storage battery repairing activator and a preparation method thereof, wherein the activator comprises 15-30 parts by weight of mother liquor, 3-5 parts by weight of carbon nano tubes, 4-7 parts by weight of sodium sulfate, 5-8 parts by weight of cobalt sulfate, 4-9 parts by weight of copper sulfate and 50-70 parts by weight of deionized water, wherein the mother liquor comprises 0.2-0.8% by weight of super absorbent resin, 0.5-3% by weight of fumed silica and the balance of deionized water. The waste lead-acid storage battery repairing activator accelerates the decomposition of lead sulfate which is not conductive originally, and ensures that the temperature of the storage battery is not excessively increased when the storage battery is activated by high-frequency current, so that the storage battery is effectively protected.

Description

Waste lead-acid storage battery repairing activator and preparation method thereof

Technical Field

The invention belongs to the field of waste battery recycling, and particularly relates to a waste lead-acid storage battery repairing activator and a preparation method thereof.

Background

China is one of the world lead-acid storage battery producing and selling major countries, and the lead-acid storage battery, as the most main stable power supply and direct-current power supply, has a long history and is widely used. The shadow of the lead-acid storage battery is active in various industries such as telecommunication, electric power, finance, automobiles, railways, steamships, radio and television, solar energy, wind energy, national defense and the like, and particularly, along with the rapid development of the industries of automobiles and electric bicycles, the problem of scrapping of the battery becomes a focus of attention of governments and users in various countries when the lead-acid storage battery is used in large quantity. The lead-acid storage battery repair and maintenance has become an industry of hundreds of millions of dollars every year, and the government supports and protects the lead-acid storage battery from financial and tax policies.

The life of a lead-acid battery is determined mainly by the rate of corrosion deformation of the positive grid and the rate of accumulation of irreversible sulfation, if production quality and abnormal use are not considered. Generally, the period from grid corrosion to ultimate failure is long, and irreversible sulfation is the most major and common cause of battery life. The abandonment of the lead-acid storage battery is caused by the deformation of a plate grid of a polar plate and the falling of an active substance in the repeated charging and discharging process. From the theory of porous electrodes, the plate of lead-acid battery belongs to two-phase porous electrode (fully immersed diffusion electrode). When the electrode works, the electrolyte permeates into the pores of the porous electrode, and electrode reaction is carried out on a liquid-solid two-phase interface. In this case, the contact area between the active material on the electrode plate and the electrolyte is large, and the electrochemical reaction is likely to occur during normal charge and discharge. However, because the application state is complicated and changeable, it is difficult to ensure the theoretical "normal charge and discharge" condition. Most lead-acid storage batteries, especially fixed batteries in a float charge state, undergo irreversible sulfation to different degrees in use, i.e., a layer of coarse, hard and insoluble lead sulfate recrystallization crystals is formed on the polar plates. It blocks the capillary pores and the outer surface of the plate, thus preventing the electrolyte from reacting with the active substance, reducing the action of the active substance and finally causing the failure of the battery capacity. Lead-acid batteries, which are normally used, form lead sulfate crystals during discharge and can be relatively easily reduced to lead during charging. If the battery is used and maintained badly, for example, left unused for a long time or frequently under-charged, over-discharged, etc., a coarse and hard lead sulfate crystal is gradually formed on the negative electrode. Such lead sulfate crystals are non-conductive and are difficult to decompose in conventional charging regimes. This phenomenon is called "irreversible sulfation". It causes an increase in the internal resistance and a decrease in the capacity of the battery, and the main reason for its formation is that the recrystallization phenomenon of lead sulfate causes a decrease in the solubility after the formation of coarse crystals and thus cannot be decomposed. Because of the difference of the production process of the lead-acid storage battery and the fact that the battery is static for a long time and does not have convection, the layering phenomenon of the electrolyte is formed, the layering of the electrolyte of the battery can seriously affect the performance of the battery, the part with higher density can corrode a polar plate, the part with lower density reduces electrochemical reaction substances, and the layering phenomenon is also an important factor influencing the service life of the lead-acid storage battery.

The repair activator and the repair method used in the market at present can only solve the problem of lead sulfate crystallization and can not solve the problem of electrolyte layering, namely, the service life of the repair activator can not be guaranteed even if the original function can be repaired. Therefore, in order to improve the recovery effect and prolong the service life of the waste lead-acid storage battery, development of a repair activator and a repair technology of the waste lead-acid storage battery is urgently needed.

Disclosure of Invention

The invention mainly aims to develop a waste lead-acid storage battery repairing activator, determine the properties of sulfate crystals on the depth, the adhesive force and the crystal lattice phase taking of storage battery pole plates, analyze and calculate the use ration of the activator on the sulfate of the storage battery pole plates, better eliminate and avoid irreversible sulfate crystals on the storage battery pole plates and greatly increase the contact area of active substances of the pole plates and electrolyte.

According to one aspect of the invention, the waste lead-acid storage battery repairing activator is characterized by comprising 15-30 parts by weight of mother liquor, 3-5 parts by weight of carbon nano tubes, 4-7 parts by weight of sodium sulfate, 5-8 parts by weight of cobalt sulfate, 4-9 parts by weight of copper sulfate and 50-70 parts by weight of deionized water, wherein the mother liquor comprises 0.2-0.8% by weight of super absorbent resin, 0.5-3% by weight of fumed silica and the balance of deionized water.

Preferably, the super absorbent resin is a cationic resin of tertiary amine or quaternary amine.

Preferably, the super absorbent resin is at least one of ammonium polyacrylate, polyacrylamide and acrylic acid/acrylamide copolymer.

According to another aspect of the invention, a preparation method of a waste lead-acid storage battery repair activator is provided, which comprises the following steps:

(1) preparing mother liquor, adding super absorbent resin into deionized water, stirring to obtain gel, adding gas phase silicon dioxide, and uniformly stirring to obtain mother liquor;

(2) and adding deionized water into the mother liquor, then adding the carbon nano tube, the sodium sulfate, the cobalt sulfate and the copper sulfate, mixing and uniformly stirring to obtain the waste lead-acid storage battery repairing activator.

According to another aspect of the invention, a method for repairing a waste lead-acid storage battery is provided, which comprises adding the activating agent of the invention into an electrolyte of the waste lead-acid storage battery for activation.

The research of the invention finds that the gas-phase silica is uniformly dispersed in the high water-absorbing resin gel, the dispersibility of the gas-phase silica is improved, a ball-shaped homopolymerization net structure with high dispersibility of 5-15nm can be formed, and the net structure can be used for embedding different types of hydroxyl and carboxyl functional groups in a plurality of dimensions in space, so that the high water-absorbing resin gel has good hydrophilicity and thermal specific volume.

After the waste lead-acid storage battery repairing activator is contacted with the electrolyte, the electrolyte is changed into a water-in-oil colloidal state (a capsule-type colloidal state) from a water state, a large amount of sulfate ions can be contained in the capsule, the surface corrosive force of sulfuric acid is weakened, meanwhile, the sulfate ions form an ordered 'cluster' state, the viscosity of the electrolyte is reduced, the permeability is enhanced, and the layering phenomenon of the electrolyte is inhibited.

Sodium ions, cobalt ions and copper ions are added into the activating agent, so that the potential can be improved, the capacity of the battery can be improved, the strength of the polar plate can be enhanced, and the sulfation can be repaired.

The invention has the beneficial effects that: the waste lead-acid storage battery repairing activator accelerates the decomposition of lead sulfate which is not conductive originally, and ensures that the temperature of the storage battery is not excessively increased when the storage battery is activated by high-frequency current, so that the storage battery is effectively protected. The capacity of the activated waste lead-acid storage battery can reach more than 98%, and the battery capacity can still reach more than 92% after multiple fatigue experiments, such as nearly hundred fatigue experiments. The functional characteristics of the activator applied to the storage battery are shown in the following aspects:

(1) specific energy is improved, electrolyte permeability and adhesive force are enhanced, ion movement speed and collision efficiency are increased, and active substances fully react to increase the discharge capacity of the storage battery;

(2) the cycle life is prolonged, the activity of the electrolyte and the surface activity of the conversion of active substances of the polar plate are enhanced, and the electrode passivation coefficient and the corrosion coefficient are reduced due to the weakening of the surface corrosive force of sulfuric acid in the electrolyte;

(3) the low-temperature performance is good, the high thermal ratio of the electrolyte increases the stability of low-temperature impedance, and the molecular motion in a low-temperature environment is facilitated;

(4) the high-temperature performance is stable, and high-temperature-resistant nanoscale groups are embedded in the polymer chain of the electrolyte, so that the corrosion of the electrode in a high-temperature environment is slowed down;

(5) the high-current charging and discharging capacity is strong, the internal resistance of the electrolyte is reduced from milliohm level to microohm level, and the reaction speed of the electrode is increased, so that the charge transfer quantity in unit time is increased;

(6) the charging time is short, the conversion efficiency of the active material is high, the oxygen absorption of the negative electrode is effectively depolarized, and the charge acceptance is strong;

(7) lead sulfate crystals are decomposed, and the lead-acid storage battery is fundamentally repaired.

Drawings

FIG. 1 is a photograph of a crystallized polar plate of lead sulfate in a waste lead-acid storage battery;

fig. 2 is a photograph of a plate activated by a spent lead acid battery repair activator according to one embodiment of the present invention.

Detailed Description

For the purpose of clearly illustrating the aspects of the present invention, preferred embodiments are given below in conjunction with the accompanying drawings. The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses.

Example 1

A waste lead-acid storage battery repairing activator is prepared by the following preparation method:

(1) adding 0.3% of polyacrylamide into deionized water, stirring to obtain gel, adding 0.8% of fumed silica, and uniformly stirring to obtain mother liquor;

(2) and adding 60 parts of deionized water into 20 parts of mother liquor, sequentially adding 4 parts of carbon nano tubes, 5 parts of sodium sulfate, 6 parts of cobalt sulfate and 8 parts of copper sulfate, mixing, and uniformly stirring to obtain the waste lead-acid storage battery repairing activator.

Example 2

A waste lead-acid storage battery repairing activator is prepared by the following preparation method:

(1) adding 0.8% of polyacrylamide into deionized water, stirring to obtain gel, adding 2% of fumed silica, and uniformly stirring to obtain mother liquor;

(2) and adding 50 parts of deionized water into 15 parts of mother liquor, sequentially adding 3 parts of carbon nano tubes, 7 parts of sodium sulfate, 8 parts of cobalt sulfate and 4 parts of copper sulfate, mixing, and uniformly stirring to obtain the waste lead-acid storage battery repairing activator.

Example 3

A waste lead-acid storage battery repairing activator is prepared by the following preparation method:

(1) adding 0.6% of ammonium polyacrylate into deionized water, stirring to obtain gel, adding 3% of fumed silica, and uniformly stirring to obtain mother liquor;

(2) and adding 70 parts of deionized water into 30 parts of mother liquor, sequentially adding 5 parts of carbon nano tubes, 4 parts of sodium sulfate, 5 parts of cobalt sulfate and 9 parts of copper sulfate, mixing and uniformly stirring to obtain the waste lead-acid storage battery repairing activator.

Example 4

A waste lead-acid storage battery repairing activator is prepared by the following preparation method:

(1) adding 0.2% of ammonium polyacrylate into deionized water, stirring to obtain gel, adding 0.5% of fumed silica, and uniformly stirring to obtain mother liquor;

(2) and adding 60 parts of deionized water into 25 parts of mother liquor, sequentially adding 4 parts of carbon nano tubes, 5 parts of sodium sulfate, 7 parts of cobalt sulfate and 8 parts of copper sulfate, mixing and uniformly stirring to obtain the waste lead-acid storage battery repairing activator.

The waste lead-acid storage battery is repaired by using the waste storage battery repairing activator, and the specific repairing method comprises the following steps:

the recovery process of a lead-acid battery (battery for short) generally comprises the following procedures:

(1) preliminary detection of the battery: comprehensively judging the basic condition of the battery to be recovered by knowing the service condition of the battery, detecting by an instrument and the like; for example, the production date, the online service condition and the offline date of the battery to be repaired and activated are known. And (3) checking the appearance of the battery, wherein the battery shell has the phenomena of cracking, leakage and swelling, opening the liquid injection hole to check the pole, the busbar, the pole ear and the upper part of the pole plate carefully, and eliminating physical damage conditions due to the phenomena of corrosion and deformation.

(2) Initial capacity test: the method comprises the steps of judging the original capacity of a battery by performing initial charging and discharging on the battery, preparing for battery activation, and determining a processing scheme;

(3) adding an activating agent: according to the specific situation of the battery, for example, a proper amount of activating agent is injected into the electrolyte in the storage battery by using a test tube; standing for 1 hour or more so that the active ingredients of the activator are fully diffused in the battery;

(4) and (3) activation: activating and opening the storage battery injected with the activating agent under the activation current which is several times larger than the conventional charging current, gradually reducing the internal resistance and eliminating the vulcanization, thereby realizing the recycling of the lead-acid storage battery scrapped due to the vulcanization phenomenon;

(5) discharging: the discharge is an important ring in the activation process, and not only can the activation effect be checked, but also the effective components of the activator can be promoted to be deeper into the battery through the discharge.

(6) Simulating charge and discharge: and testing the charging and discharging conditions of the recovered battery, wherein the simulated charging and discharging is to charge according to a user charging mode and then discharge, and the simulated charging and discharging is to perform one-time inspection on activation repair and can be delivered to a user for use on station after inspection and repair requirements.

(7) And (3) battery sealing: the opened battery is sealed again, so that the safety of the battery is not damaged, and the normal and safe use of a user is ensured;

example 5

The activator prepared in example 1 above and the above repair method were used to repair the following lead acid batteries: the battery to be repaired is on-line in 2014 and off-line in 2017, the battery is in perfect appearance, no bulge, liquid leakage, open circuit and short circuit exist, the busbar is not broken, the active substance is not dropped, and the polar plate is not softened after the on-line operation is carried out for 4 years.

The battery is subjected to initial charging and discharging, and the capacity of the battery is detected to be 30% of the nominal capacity, which does not meet the online use requirement, but the group of lead-acid storage batteries have no physical damage and meet the repair requirement.

1ml of the activator prepared according to the present invention was added to AH (nominal capacity of the cell), and the mixture was allowed to stand for 20 hours after the addition to allow the activator to perform a sufficient permeation reaction.

The QD-ZNH80-180 intelligent storage battery activating instrument (sold in market) is used for activating, activating and repairing the lead-acid storage battery, and the method comprises the following three stages:

1) the activation stage is about 4 hours according to the current condition of the battery, and the current is 0.07 c;

2) the activation period time was 10 hours and the current was 0.12 c;

3) the charging stage time is 5 hours, and the current is 0.1 c;

and after the activation is finished, discharging at a rate of 10 hours when the temperature of the battery is reduced to below 25 ℃, wherein the capacity of the repaired lead-acid storage battery is 100% of the nominal capacity, and the individual differential pressure is less than 0.02 v.

And then carrying out simulated charging and discharging: the simulation charging and discharging is to charge according to the user charging mode and then discharge, the simulation charging and discharging is to carry out one-time inspection on activation repair, and the simulation charging and discharging can be delivered to a user for use when the user is on station after the inspection and repair requirements.

Fig. 1 shows a microscopic crystallized plate of lead sulfate from a waste lead-acid battery, and it can be seen from fig. 1 that a layer of coarse hard and insoluble heavy crystals of lead sulfate are formed on the plate. After the activation and restoration of the activating agent, as shown in figure 2, the large crystals on the polar plate are all decomposed, the acid radical ions of the electrolyte are greatly increased, and the specific gravity is also restored to a normal level. The battery is restored to a new initial state. For most of the storage batteries which are normally used, the storage batteries can be continuously operated for one service cycle after the recovery processing.

Example 6

The activator prepared in example 3 above and the above repair method were used to repair the following lead acid batteries: the online storage battery pack for the base station is used for a certain period, the battery capacity is checked through load discharge, and the battery with the capacity less than 80 percent but still more than 65 percent is judged to be a sub-healthy battery;

the repair was carried out in substantially the same manner as in example 5, except that: discharging by using a base station load until the voltage of the single battery is 1.9V, recovering the charging state, and charging for the first time by using balanced voltage; sealing the sealing valve after the equalizing charge is finished; the battery achieves the best repairing and activating effects through three charging and discharging cycles.

The lead-acid storage battery does not need to be offline, and the normal work of the base station is not influenced. However, it should be noted that the addition of the activator should be done slowly to prevent spillage, with protective gloves of glue, and with goggles which may be rinsed with clear water if they are spilled on the skin.

Example 7 fatigue test

Fatigue tests were conducted on the activated lead-acid batteries of example 5 to determine the service life of the regenerated batteries, and the tests were conducted by charging the batteries at the bottom of the battery at peak-to-valley electricity rates every day and then discharging the batteries at a rate of 10 hours to a single stop position of 1.9V for one charge-discharge cycle, and the average capacity of the lead-acid batteries is shown in table 1.

TABLE 1 fatigue test effect table for lead-acid storage battery

Time of day	Number of charge and discharge cycles	Average capacity
			1 month	30 times (twice)	93.1％
2 months old	60 times	92.6％
			The time is not limited	86 times (twice)	92.3％

As can be seen from Table 1, the repairing effect of the waste lead-acid storage battery repaired by the activating agent is obvious, and the capacity of the waste lead-acid storage battery does not form an obvious reduction trend after 86 times of charge-discharge cycles, so that the waste lead-acid storage battery has a better technical effect.

In summary, the above descriptions are only examples of the present invention, and are only used for illustrating the principles of the present invention, and not for limiting the protection scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (5)

1. The waste lead-acid storage battery repairing activator is characterized by comprising 15-30 parts by weight of mother liquor, 3-5 parts by weight of carbon nano tubes, 4-7 parts by weight of sodium sulfate, 5-8 parts by weight of cobalt sulfate, 4-9 parts by weight of copper sulfate and 50-70 parts by weight of deionized water, wherein the mother liquor comprises 0.2-0.8% by weight of super absorbent resin, 0.5-3% by weight of fumed silica and the balance of deionized water.

2. The agent as claimed in claim 1, wherein the high water absorption resin is cationic resin of tertiary amine or quaternary amine.

3. The repairing activator for waste lead-acid storage batteries according to claim 2, characterized in that the super absorbent resin is at least one of ammonium polyacrylate, polyacrylamide and acrylic acid/acrylamide copolymer.

4. A process for the preparation of a repair activator for waste lead-acid batteries according to any one of claims 1 to 3, comprising the following steps:

(1) preparing mother liquor, adding super absorbent resin into deionized water, stirring to obtain gel, adding fumed silica, and uniformly stirring to obtain mother liquor;

(2) and adding deionized water into the mother liquor, then adding the carbon nano tube, the sodium sulfate, the cobalt sulfate and the copper sulfate, mixing and uniformly stirring to obtain the waste lead-acid storage battery repairing activator.

5. A method for repairing a used lead-acid storage battery, comprising adding the activator according to any one of claims 1 to 3 to an electrolyte of the used lead-acid storage battery for activation.

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