Lead-acid storage battery repair liquid as well as preparation method and application thereof

Abstract

The invention provides lead-acid storage battery repair liquid as well as a preparation method and application thereof. The lead-acid storage battery repair liquid comprises water and the following preparation raw materials in percentage by mass: 0.2%-2% of polyvinylpyrrolidone, 0.3%-3% of nano cellulose, 0.5%-5% of cobaltous sulfate, 0.3%-3% of nano metal oxide, 0.3%-3% of mannitol, 0.3%-3% of amino acid, 0.5%-5% of etidronic acid, 0.5%-3% of quaternary ammonium salt, 0.3%-3% of an anionic surfactant and 0.05%-1% of carbon nanotubes. The nano metal oxide is compounded by bismuth oxide, cobalt oxide and manganese oxide according to the mass ratio of 1: (0.5-1.5): (1-3). The lead-acid storage battery repairing liquid can efficiently remove lead sulfate deposition on a polar plate, and the battery capacity recovery rate is remarkably improved. The invention also provides a preparation method and application of the lead-acid storage battery repair liquid.

Description

Technical Field

[0001] This invention relates to the field of lead-acid battery technology, specifically to a lead-acid battery repair fluid, its preparation method, and its application. Background Technology

[0002] Lead-acid batteries are widely used in vehicle starting power, communication and emergency backup power, and energy storage systems due to their low cost, high reliability, and long cycle life. However, with prolonged use, battery capacity gradually decreases and may even fail, with irreversible sulfation (commonly known as "sulfation") being one of the main causes. Sulfation refers to the gradual accumulation of lead sulfate on the electrode surface during discharge, which is not completely reduced during charging. If the battery is left undercharged for an extended period or improperly stored, the lead sulfate crystals will gradually grow and densify, forming large, difficult-to-reduce deposits, leading to increased internal resistance, reduced electrochemical activity, and a sharp decline in battery capacity.

[0003] Existing lead-acid battery repair technologies mainly include chemical repair, high-current charging, and pulse repair. Although these methods can improve the problem of plate sulfation to some extent, the capacity recovery rate is limited, and improper handling may aggravate battery damage, especially for severely sulfated batteries, making it difficult to restore them to near-rated capacity.

[0004] Therefore, there is an urgent need to develop a high-performance lead-acid battery repair fluid that can efficiently remove lead sulfate deposits on the plates, improve capacity recovery rate, and avoid secondary damage to the battery, thereby significantly extending the service life of lead-acid batteries. Summary of the Invention

[0005] This invention provides a lead-acid battery repair fluid that can efficiently remove lead sulfate deposits on the plates, significantly improve the battery capacity recovery rate, and extend the battery's service life.

[0006] The present invention also provides a method for preparing a lead-acid battery repair fluid.

[0007] The present invention also provides a method for repairing lead-acid batteries.

[0008] Specifically, the first aspect of the present invention relates to a lead-acid battery repair solution, comprising water and the following preparation ingredients by mass percentage: Polyvinylpyrrolidone 0.2%-2%, nanocellulose 0.3%-3%, cobalt sulfate 0.5%-5%, nano-metal oxides 0.3%-3%, mannitol 0.3%-3%, amino acids 0.3%-3%, hydroxyethylidene diphosphonic acid 0.5%-5%, quaternary ammonium salts 0.5%-3%, anionic surfactants 0.3%-3%, carbon nanotubes 0.05%-1%; The nano-metal oxide is a compound of bismuth oxide, cobalt oxide and manganese oxide in a mass ratio of 1:0.5-1.5:1-3.

[0009] The lead-acid battery repair fluid according to the first aspect of the present invention has at least the following beneficial effects: Polyvinylpyrrolidone (PVP) provides excellent dispersion stability, ensuring uniform dispersion of solid components. Nanocellulose, with its polyhydroxy structure and high specific surface area, enhances solution adhesion, forming a uniform coating layer on the electrode surface, promoting subsequent electrochemical activation and dissolution processes while inhibiting the sedimentation of solid particles.

[0010] Bismuth oxide possesses strong redox properties, promoting the decomposition of lead sulfate and improving the electrochemical reaction efficiency of the repair solution, especially significantly enhancing the electrochemical repair effect during charging. Cobalt oxide exhibits high catalytic activity, accelerating the conversion of lead sulfate into active substances. Manganese oxide generates active sites on the electrode surface, promoting the conversion of lead sulfate into soluble ions and inhibiting lead sulfate redeposition. The combination of bismuth oxide and manganese oxide effectively reduces sulfide deposition, while cobalt oxide further enhances the overall reaction rate, achieving rapid and efficient repair.

[0011] Cobalt sulfate provides cobalt ions, promoting the catalytic effect of cobalt oxide and accelerating the lead sulfate reduction process. As the degree of battery sulfation increases, appropriately increasing the proportion of cobalt sulfate is beneficial for further improving capacity recovery efficiency.

[0012] Hydroxyethylidene diphosphonic acid (HEDTA) chelates lead ions, gently dissolving the sulfate layer without excessively interfering with the redox reaction of the lead electrode, while also causing minimal corrosion to the electrode substrate. Mannitol exhibits good permeability, promoting the penetration of the repair solution into the electrode pores and forming a flexible protective film on the surface, inhibiting lead sulfate redeposition; its polyhydroxy structure can weakly complex with metal ions such as lead, acting as a buffer and diluent, inhibiting lead sulfate crystal growth. Amino acids form complexes with lead ions through multidentate coordination, synergistically working with the chelating agent to make the lead sulfate dissolution process more stable and controllable.

[0013] The combination of anionic surfactants and PVP significantly reduces the surface tension of the repair solution, enhances its wettability on the active layer of the electrode, and allows the repair solution to fully penetrate into the pores of the electrode and the gaps between lead sulfate crystals.

[0014] Carbon nanotubes can provide electron transport pathways, promote the electrochemical reduction of lead sulfate, and improve the electrochemical efficiency in the battery repair process.

[0015] In summary, the various functional components in the repair solution work together to achieve multiple functions such as dispersion, dissolution, electrochemical activation, and surface protection. It can efficiently remove lead sulfate deposits on the plates under mild conditions and restore the structure of active materials. It is particularly suitable for lead-acid batteries whose capacity has significantly decreased due to lead sulfate deposits, and can significantly improve the capacity recovery rate and extend the battery life.

[0016] According to some embodiments of the present invention, the average particle size of the nano-metal oxide is 50-500 nm, for example, 100-200 nm.

[0017] According to some embodiments of the present invention, the mass ratio of bismuth oxide, cobalt oxide and manganese oxide is 1:1-1.2:1.5-2, for example 1:1.05-1.15:1.6-1.8.

[0018] According to some embodiments of the present invention, the nano-metal oxide is 1%-3%, for example 1.5%-2.5%.

[0019] According to some embodiments of the present invention, the number-average molecular weight of the PVP is 20,000-80,000, for example, 40,000-60,000.

[0020] According to some embodiments of the present invention, the PVP is 0.5%-1%.

[0021] According to some embodiments of the present invention, the nanocellulose has a diameter of 10-100 nm and a length of 0.5-10 μm. For example, a diameter of 10-50 nm and a length of 0.5-5 μm.

[0022] According to some embodiments of the present invention, the nanocellulose is 1%-2%.

[0023] According to some embodiments of the present invention, the amino acid is selected from at least one of glycine and glutamic acid.

[0024] According to some embodiments of the present invention, the amino acid content is 0.5%-1%.

[0025] According to some embodiments of the present invention, the anionic surfactant is sodium fatty alcohol polyoxyethylene ether sulfate (AES), which is beneficial for improving the permeability and dispersibility of the repair solution.

[0026] According to some embodiments of the present invention, the anionic surfactant is 1%-1.5%.

[0027] According to some embodiments of the present invention, the quaternary ammonium salt is selected from hexadecyltrimethylammonium bromide (CTAB).

[0028] According to some embodiments of the present invention, the quaternary ammonium salt is 0.5%-0.8%.

[0029] According to some embodiments of the present invention, the carbon nanotube is a multi-walled carbon nanotube with a diameter of 10-30 nm and a length of 5-30 μm.

[0030] According to some embodiments of the present invention, the carbon nanotubes are 0.1%-0.3%.

[0031] According to some embodiments of the present invention, the raw materials for preparation satisfy at least one of the following conditions: (1) The cobalt sulfate is 1%-3%, for example, 1%-2%; (2) The mannitol content is 0.5%-2%, for example, 0.5%-1.5%; (3) The hydroxyethylidene diphosphonic acid is 1%-3%, for example, 1%-2%.

[0032] The second aspect of the present invention relates to a method for preparing the lead-acid battery repair fluid, comprising the steps of: dispersing polyvinylpyrrolidone and nanocellulose in water, adding sulfate, mannitol, amino acids, hydroxyethylidene diphosphonic acid, anionic surfactant and quaternary ammonium salt and mixing, and then adding conductive agent and nanometal oxide and mixing to obtain the solution.

[0033] The dispersion of the conductive agent and nano-metal oxide can be achieved by ultrasonic treatment; the overall mixing process can be carried out in conjunction with heating or stirring, but the specific operating conditions are not limited and can be adjusted by those skilled in the art based on experience.

[0034] The third aspect of this invention relates to a method for repairing a lead-acid battery, comprising the steps of: Add the lead-acid battery repair fluid to the lead-acid battery cell to be repaired, let it stand, and then use the high-frequency pulse method and the balanced resonance pulse method to repair it in sequence.

[0035] After adding the lead-acid battery repair solution to the individual battery cells to be repaired, the cells are allowed to stand to allow the solution to fully wet the pores of the electrode plates and come into contact with the lead sulfate deposits, forming a preliminary chemical dissolution and complexation environment. Subsequently, electrochemical repair is performed sequentially using a high-frequency pulse method and a balanced resonant pulse method, achieving a synergistic effect of chemical action and electrochemical activation, thus improving repair efficiency. This method has high lead sulfate dissolution efficiency, significantly improving the capacity of the failed battery, and does not damage the electrode plate structure.

[0036] In the high-frequency pulse stage, micro-vibrations and interface disturbances are generated by high-frequency electric field excitation, causing lead sulfate crystals to loosen or desorb; in the balanced resonance pulse stage, lead sulfate crystals are gradually reduced to active materials under relatively mild electrochemical conditions, thereby achieving plate regeneration and capacity recovery.

[0037] According to some embodiments of the present invention, the amount of lead-acid battery repair fluid added is 1-1.5 mL / Ah / cell, for example 1-1.2 mL / Ah / cell.

[0038] According to some embodiments of the present invention, the settling time is 2-4 hours.

[0039] According to some embodiments of the present invention, the parameters of the high-frequency pulse method are as follows: sawtooth wave, frequency 20-50kHz, duty cycle 10%-30%, voltage amplitude 2.5-3V / cell, and processing time 0.5-1h. For example, frequency 20-40kHz, duty cycle 15%-25%, and voltage amplitude 2.8-3V / cell.

[0040] According to some embodiments of the present invention, the parameters of the equalized resonant pulse method are as follows: square wave, frequency 5-10kHz, duty cycle 40%-50%, voltage amplitude 2-2.5V / unit, and processing time 1-3h. For example, frequency 5-8kHz, duty cycle 45%-50%, voltage amplitude 2.2-2.3V / unit, and processing time 2h-3h.

[0041] In this article, the term "room temperature" refers to 23±2℃.

[0042] The term "about" indicates an error range of ±2% and follows the rounding rules, meaning that all values ​​within this error range are rounded to the nearest significant figure.

[0043] In this article, the numerical ranges mentioned all include the endpoint values ​​and cover any subranges within that range, such as the ranges obtained by arbitrarily combining the specifically listed numerical values.

[0044] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Detailed Implementation

[0045] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0046] In the following embodiments: Bismuth oxide, purchased from Yumu (Ningbo) New Materials Co., Ltd., with an average particle size of 150 nm; nano cobalt oxide and nano manganese oxide, both with an average particle size of 200 nm, were purchased from Shanghai Xiaohuang Nanotechnology Co., Ltd.

[0047] Nanocellulose, purchased from Wuhan Lanabai Pharmaceutical Chemical Co., Ltd., has a diameter of 10-50 nm and a length of 0.5-3 μm.

[0048] Carbon nanotubes: Multi-walled carbon nanotubes with a diameter of 10-20 nm and a length of 10-30 μm, purchased from Pioneer Nano.

[0049] Unless otherwise specified in the examples, the procedures should be performed under standard conditions or conditions recommended by the manufacturer. Reagents or instruments whose manufacturers are not specified are all conventional products that can be manufactured using existing technology or are commercially available.

[0050] Example 1 The raw materials for preparing lead-acid battery repair fluid are as follows: PVP (K30) 1.0%, nanocellulose 1.5%, cobalt sulfate 1.8%, nano metal oxides 2% (the mass ratio of bismuth oxide, cobalt oxide and manganese oxide is approximately 1:1.1:1.7), mannitol 1%, glycine 0.8%, hydroxyethylidene diphosphonic acid 1.5%, CTAB 0.8%, AES 1.2%, carbon nanotubes 0.2%, and the balance is deionized water.

[0051] The preparation method is as follows: S11. Add 70% of the total amount of deionized water to the mixing vessel, turn on the mechanical stirrer at room temperature, set the stirring speed to 300 rpm, add PVP and nanocellulose in sequence, and continue stirring for 15 to 20 minutes to form a uniformly dispersed system.

[0052] S12. Add cobalt sulfate, mannitol, glycine, hydroxyethylidene diphosphonic acid, AES and CTAB, and stir at 60°C for 20 to 30 minutes (800 rpm) to obtain a dispersion.

[0053] S13, carbon nanotubes, and nano-metal oxides are pre-dispersed in the remaining deionized water and ultrasonically dispersed for 15 minutes at an ultrasonic power of 300W to obtain a homogeneous slurry. The slurry is then slowly added to the dispersion, stirred at 400 rpm, heated to 40 ℃, and stirred for 20 minutes to ensure thorough mixing of all components. The mixture is then cooled to room temperature to obtain the lead-acid battery repair solution.

[0054] Battery to be repaired: 6-GFM-150, rated voltage 12V, nominal capacity of 150Ah at 20-hour rate, actual capacity of approximately 60Ah, only 40% of the nominal capacity. The battery open circuit voltage is normal, and the plates do not show obvious softening or detachment. The failure mode is mainly sulfation.

[0055] Repair the battery: S21. The repair solution is calculated based on the battery cell capacity and injected into the battery at a rate of 1.2 mL / Ah (180 mL of repair solution per cell). After injection, let stand for 3 hours.

[0056] S22. Activation is performed using a self-made activator. Specifically, the battery is physically repaired using a high-frequency pulse repair method: the output waveform is a sawtooth wave with a frequency of 30kHz, a duty cycle of 20%, a peak voltage of approximately 2.9V / cell, and a processing time of 0.8 hours.

[0057] S23. Activate the battery using a self-made battery activator. Specifically, physically repair the battery using the balanced resonant pulse repair method: output square wave, frequency 6kHz, duty cycle 48%, voltage amplitude 2.25V / cell, processing time 2.5 hours.

[0058] In steps S22 and S23, the equipment used is a device that can flexibly adjust relevant parameters. The implementation principle of this device is a well-known technology and can be obtained through custom processing or commercial purchase.

[0059] According to GB / T5008.1-2023 "Starting Lead-acid Batteries Part 1: Technical Conditions and Test Methods", the 20-hour rate capacity was tested with a discharge current of 7.5A. After repair, the capacity is approximately 142Ah, and the capacity recovery rate reaches 94.7% (relative to the nominal capacity).

[0060] Example 2: Compared with Example 1, the difference lies in the different raw materials used in the preparation of the lead-acid battery repair fluid, as follows: the amount of cobalt sulfate is adjusted to 2%, mannitol is increased to 1.5%, and the amount of hydroxyethylidene diphosphonic acid is 2%.

[0061] The repair process was performed using the same steps as in Example 1. The 20-hour rate capacity was tested using the same method as in Example 1, and the repaired capacity was approximately 145 Ah, representing a capacity recovery rate of 96.7%.

[0062] Example 3: Compared with Example 1, the difference lies in the battery repair method, as follows: In the high-frequency pulse method, the frequency is adjusted to 40kHz, the voltage amplitude is maintained at 2.9V / cell, and the duty cycle is adjusted to 25%; in the equalization resonance pulse method, the frequency is 7kHz, the duty cycle is 50%, the voltage amplitude is 2.3V / cell, the processing time is 2 hours, and the other conditions remain unchanged.

[0063] The 20-hour rate capacity was tested using the same method as in Example 1. The capacity after repair was 140 Ah, and the capacity recovery rate was 93.3%.

[0064] Comparative Example 1 Compared to Example 1, only high-frequency pulse repair was used, with a repair time of 3.3 hours, and other conditions remained unchanged. The 20-hour rate capacity was tested using the same method as in Example 1. The repaired capacity was approximately 121 Ah, with a capacity recovery rate of 80.7%, indicating that high-frequency pulse repair alone has limited effectiveness for deeply sulfurized batteries.

[0065] Comparative Example 2 Compared to Example 1, only equalized resonant pulses were used for repair, with a repair time of 3.3 hours, and other conditions remained unchanged. The 20-hour rate capacity was tested using the same method as in Example 1, and the repaired capacity was approximately 110 Ah, representing a capacity recovery rate of 73.3%. The results indicate that repair using equalized resonant pulses alone is significantly less effective than the composite repair method combined with high-frequency pulses.

[0066] Comparative Example 3 Compared to Example 2, the difference lies in the combination of bismuth oxide, cobalt oxide, and manganese oxide in a mass ratio of 1:1.1:0.4. The 20-hour rate capacity was tested using the same method as in Example 1, and the post-repair capacity was approximately 135 Ah, with a capacity recovery rate of 90%. This indicates that different combinations of nano-metal oxides have a significant impact on the repair effect.

[0067] Comparative Example 4 Compared to Example 2, hydroxyethylidene diphosphonic acid (HEDTA) was replaced with EDTA. The 20-hour rate capacity was tested using the same method as in Example 1, and the restored capacity was approximately 126 Ah, representing a capacity recovery rate of 84%. This indicates that HEDTA is more effective than EDTA in repairing lead-acid batteries, which may be related to the moderate complexing force between HEDTA and lead ions.

[0068] Comparative Example 5 Compared to Example 1, the AES in the repair solution was completely replaced with the same mass of CTAB. The 20-hour rate capacity was tested using the same method as in Example 1, and the repaired capacity was approximately 119 Ah, with a capacity recovery rate of 79.3%. It is evident that the repaired capacity decreased significantly when CTAB was used alone, possibly indicating that CTAB has a limited impact on the permeability and dispersibility of the repair solution.

[0069] Comparative Example 6 Compared to Example 1, no carbon nanotubes were added. The 20-hour rate capacity was tested using the same method as in Example 1, and the restored capacity was approximately 116 Ah, representing a capacity recovery rate of 77.3%. This may indicate that the carbon nanotubes played a role in electron conduction during the restoration process, enhancing the electrochemical reduction rate of lead sulfate.

[0070] In summary, the combination of components in the repair solution can effectively remove lead sulfate deposits on the electrode surface, significantly restore battery capacity, and is particularly suitable for lead-acid batteries whose capacity has significantly decreased due to lead sulfate deposits, thus significantly extending battery life.

[0071] The present invention has been described in detail above with reference to the embodiments, but the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A lead-acid battery repair liquid, characterized by, The lead-acid battery repair liquid comprises water and the following preparation raw materials by mass percentage: Polyvinylpyrrolidone 0.2%-2%, nanocellulose 0.3%-3%, cobalt sulfate 0.5%-5%, nanometal oxide 0.3%-3%, mannitol 0.3%-3%, amino acid 0.3%-3%, hydroxyethylidene diphosphonic acid 0.5%-5%, quaternary ammonium salt 0.5%-3%, anionic surfactant 0.3%-3%, carbon nanotube 0.05%-1%; The nanometal oxide is compounded by bismuth oxide, cobalt oxide and manganese oxide with a mass ratio of 1:0.5-1.5:1-3.

2. The lead-acid battery repair liquid according to claim 1, characterized in that, The mass ratio of the bismuth oxide, cobalt oxide and manganese oxide is 1:1-1.2:1.5-2; and / or, the particle size of the nanometal oxide is 50-500nm; and / or, the nanometal oxide is 1%-3%.

3. The lead-acid battery repair liquid according to claim 1, characterized in that, The number average molecular weight of the polyvinylpyrrolidone is 20000-80000; and / or, the polyvinylpyrrolidone is 0.5%-1%; And / or, the diameter of the nanocellulose is 10-100nm, and the length is 0.5-10μm; and / or, the nanocellulose is 1%-2%.

4. The lead-acid battery repair liquid of claim 1, wherein The amino acid is selected from at least one of glycine and glutamic acid; and / or, the amino acid is 0.5%-1%; And / or, the anionic surfactant is sodium fatty alcohol polyoxyethylene ether sulfate; and / or, the anionic surfactant is 1%-1.5%; And / or, the quaternary ammonium salt is selected from cetyltrimethylammonium bromide; and / or, the quaternary ammonium salt is 0.5%-0.8%.

5. The lead-acid battery repair liquid of claim 1, wherein The carbon nanotube is multi-walled carbon nanotube with a diameter of 10-30nm and a length of 5-30μm; and / or, the carbon nanotube is 0.1%-0.3%.

6. The lead-acid battery repair liquid of claim 1, wherein The preparation raw materials meet at least one of the following conditions: (1) The cobalt sulfate is 1%-3%; (2) The mannitol is 0.5%-2%; (3) The hydroxyethylidene diphosphonic acid is 1%-3%.

7. The preparation method of the lead-acid battery repair liquid according to any one of claims 1-6, comprising the steps of: dispersing polyvinylpyrrolidone and nanocellulose in water, adding sulfate, mannitol, amino acid, hydroxyethylidene diphosphonic acid, anionic surfactant and quaternary ammonium salt mixture, and then adding conductive agent and nanometal oxide mixture to obtain the lead-acid battery repair liquid.

8. A method of repairing a lead-acid battery, characterized in that, comprising the steps of: adding the lead-acid battery repair liquid according to any one of claims 1-6 into the lead-acid battery monomer to be repaired, standing, and then sequentially repairing by high-frequency pulse method and equalization resonance pulse method.

9. The repair method of claim 8, wherein, The adding amount of the lead-acid battery repair liquid is 1-1.5mL / Ah / monomer; and / or, the standing time is 2-4h.

10. The method of repairing according to claim 8, wherein, The parameters of the high-frequency pulse method are as follows: sawtooth wave, frequency 20-50kHz, duty cycle 10%-30%, voltage amplitude 2.5-3V / monomer, and processing time 0.5-1h; and / or, The parameters of the equalization resonance pulse method are as follows: square wave, frequency 5-10kHz, duty cycle 40%-50%, voltage amplitude 2-2.5V / monomer, and processing time 1-3h.