Preparation method of rare earth alloy for lead-acid storage battery

Abstract

The invention relates to the technical field of lead-acid storage batteries, in particular to a preparation method of a rare earth alloy for a lead-acid storage battery, which comprises the following steps: smelting refined lead and rare earth elements in a crucible electric furnace; the heating rate of the crucible electric furnace at each collection moment is adjusted; after smelting is finished, rare earth alloy liquid is obtained, and an intermediate rare earth alloy is prepared through an ingot casting technology; the method comprises the following steps: melting refined lead in a lead melting pot, heating, sequentially adding silver and sodium, stirring, heating again, adding calcium-aluminum alloy, tin and a protective agent, smelting, adding the intermediate rare earth alloy, keeping a heating state, and stirring to obtain the positive grid rare earth alloy. The heating rate in the rare earth alloy smelting process is adjusted, the rare earth element utilization rate is increased, and rare earth alloy elements are evenly distributed.

Description

Technical Field

[0001] The present application relates to the technical field of lead-acid batteries, and in particular to a method for preparing a rare earth alloy for lead-acid batteries. Background Art

[0002] The activity of rare earth elements is second only to alkali metals and alkaline earth metals. Adding rare earth elements in the preparation of lead-acid battery positive grid alloy can improve the corrosion resistance of the positive grid alloy and improve the impedance characteristics of the anode film in the lead-acid battery. Therefore, in the preparation of lead-acid battery positive grid alloy, the addition of rare earth elements can improve the corrosion resistance and conductivity of the alloy grid, reduce the formation of passivation film, and thus improve the performance and service life of the lead-acid battery.

[0003] For example, the Chinese invention patent with patent number CN201811543700.X discloses a lead-acid battery positive grid of lead-calcium-tin-copper rare earth alloy and its manufacturing method, by successively preparing a copper rare earth master alloy and a lead-calcium-tin-copper rare earth alloy, and preparing the positive grid in the lead-acid battery by the lead-calcium-tin-copper rare earth alloy. The patent does not control the heating rate during the smelting process of the rare earth alloy. If the heating is too fast or too slow, it may cause uneven distribution of components in the alloy, thereby affecting the final performance of the alloy. Summary of the invention

[0004] In view of the above, it is necessary to provide a method for preparing a rare earth alloy for lead-acid batteries to solve the above problems.

[0005] One embodiment of the present application provides a method for preparing a rare earth alloy for a lead-acid battery, the method comprising: Step 1: Smelting refined lead and rare earth elements in a crucible electric furnace; the smelting temperatures of all sampling points in the crucible electric furnace at each sampling moment during the smelting process are combined into a smelting temperature matrix at each sampling moment; Step 2: Analyze the temperature change distribution characteristics in the horizontal and vertical directions in the melting temperature matrix at each acquisition time, and obtain all melting feature vectors at each acquisition time; based on the difference between each element and the other elements in each melting feature vector at each acquisition time, obtain the melting uniformity of each element to form each uniform feature vector at each acquisition time; Step 3: According to the difference between the uniform feature vectors at each collection time, combined with the element distribution characteristics of the uniform feature vector, the smelting effectiveness at each collection time is obtained, and the heating rate of the crucible electric furnace at each collection time is adjusted; after the smelting is completed, the rare earth alloy liquid is obtained, and the intermediate rare earth alloy is prepared by the ingot casting process; Step 4: Melt the refined lead in a lead melting pot, add silver and sodium in turn after heating and stir, heat up again and add calcium aluminum alloy, tin and protective agent for smelting, add the intermediate rare earth alloy and keep heating, stir to obtain the positive electrode grid rare earth alloy.

[0006] Preferably, the rare earth element is lanthanum, samarium, cerium or yttrium.

[0007] Preferably, the temperature range for smelting the refined lead and the rare earth elements in the crucible electric furnace is 600-1000°C.

[0008] Preferably, the smelting characteristic vector includes a longitudinal smelting characteristic vector and a transverse smelting characteristic vector, and the acquisition steps are: Obtain the first-order difference vector of each row vector in the melting temperature matrix at each acquisition moment, and calculate the absolute value of all elements in the first-order difference vector to obtain each lateral temperature difference change vector at each acquisition moment; Calculate the permutation entropy of each transverse temperature difference change vector at each acquisition moment, and use the vector composed of the permutation entropy of all transverse temperature difference change vectors at each acquisition moment as the longitudinal melting characteristic vector at each acquisition moment; The same method as the longitudinal melting characteristic vector is used to obtain the transverse melting characteristic vector at each collection moment according to each column vector in the capacity-temperature matrix at each collection moment.

[0009] Preferably, the smelting uniformity includes longitudinal smelting uniformity and transverse smelting uniformity; the uniform characteristic vector includes longitudinal uniform characteristic vector and transverse uniform characteristic vector, specifically: For each element in the longitudinal melting characteristic vector, the absolute value of the difference between each element and the remaining elements is obtained, the absolute value of the difference between each element and all the remaining elements is accumulated and then negatively correlated to obtain the longitudinal melting uniformity of each element; the vector composed of the longitudinal melting uniformity of all elements in the longitudinal melting characteristic vector at each acquisition moment is recorded as the longitudinal uniformity characteristic vector at each acquisition moment; The same method as that for the longitudinal smelting uniformity is adopted to obtain the transverse smelting uniformity of the transverse smelting characteristic vector based on the transverse smelting characteristic vector; the vector composed of the transverse smelting uniformity of all elements in the transverse smelting characteristic vector at each acquisition moment is recorded as the transverse uniformity characteristic vector at each acquisition moment.

[0010] Preferably, obtaining the smelting effectiveness at each collection time includes: Align the longitudinal uniform feature vector and the transverse uniform feature vector at each acquisition moment, calculate the difference vector between the two vectors, and record the average of the absolute values ​​of all elements in the difference vector as the directional difference at each acquisition moment; The mean of all elements in the longitudinal uniform feature vector at each acquisition moment is recorded as the first mean; the mean of all elements in the transverse uniform feature vector at each acquisition moment is recorded as the second mean; the first mean and the second mean are fused, and then fused with the negative correlation mapping result of the directional difference at each acquisition moment to obtain the smelting utility at each acquisition moment.

[0011] Preferably, the calculation method for adjusting the heating rate of the crucible electric furnace at each collection moment is: , where is the heating rate of the crucible electric furnace at the next sampling moment, is the heating rate of the crucible electric furnace at the current collection time, is the smelting efficiency at the current collection time, is the preset judgment threshold, It is the preset maximum adjustment value of the heating rate. Represents an exponential function with a natural constant as base.

[0012] Preferably, silver and sodium are added in sequence after the heating and stirred, wherein the temperature is raised to 500-550°C.

[0013] Preferably, the temperature for smelting after heating again and adding calcium aluminum alloy, tin and protective agent is 600-650°C.

[0014] Preferably, during the process of adding the intermediate rare earth alloy and stirring, the temperature needs to be kept elevated and stirred for 20 minutes.

[0015] This application has at least the following beneficial effects: (1) The present application analyzes the smelting uniformity of rare earth elements in different directions in a crucible electric furnace, and adjusts the heating rate during the smelting process of rare earth elements by using the smelting efficiency characteristics of the rare earth elements in the crucible electric furnace. The heating rate during the smelting process can be adjusted more accurately, thereby ensuring that the rare earth elements in the alloy liquid are fully melted together, improving the utilization rate of the rare earth elements, making the rare earth alloy elements evenly distributed, and enhancing the performance of the positive electrode grid rare earth alloy.

[0016] (2) The present application adjusts the rare earth elements during the smelting process by means of smelting efficiency, which can reduce the electrical energy consumption used in the process while keeping the rare earth elements in the alloy liquid fully smelted together. The operation is simple, which can effectively shorten the production cycle, reduce the production input cost, and alleviate the environmental pressure.

[0017] (3) The present application adopts rare earth elements such as lanthanum, samarium, cerium, and yttrium to prepare positive electrode grid rare earth alloy, which is used in the preparation of lead-acid batteries. It can significantly improve the corrosion resistance and conductivity of the positive electrode grid of the lead-acid battery, reduce the formation of passivation film, and thus improve the performance and service life of the lead-acid battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A flow chart of a method for preparing a rare earth alloy for a lead-acid battery provided in the present application; Figure 2 This is a process flow chart for preparing the positive electrode grid rare earth alloy provided for this application. DETAILED DESCRIPTION

[0019] In the description of the embodiments of the present application, words such as "exemplary", "or", "for example" and the like are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "or", "for example" and the like is intended to present related concepts in a concrete manner.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the present application. The terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application.

[0021] It should also be noted that the terms "first" and "second" in this application and its drawings are used to distinguish similar objects, rather than to describe a specific order or sequence. The method disclosed in the embodiments of the present application or the method shown in the flow chart includes one or more steps for implementing the method. Without departing from the scope of protection of this application, the execution order of multiple steps can be interchanged with each other, and some steps can also be deleted.

[0022] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0023] Example 1 Example 1 of the present application proposes a method for preparing a rare earth alloy for a lead-acid battery, which is applied to the technical field of lead-acid batteries. Figure 1 , the method comprising: Step 1: Smelting refined lead and rare earth elements in a crucible electric furnace; the smelting temperatures of all sampling points in the crucible electric furnace at each sampling moment during the smelting process are combined to form a smelting temperature matrix at each sampling moment.

[0024] Refined lead with a purity of at least 99.9% is placed in a crucible electric furnace, evacuated, nitrogen is introduced, and the temperature in the crucible electric furnace is increased. Subsequently, rare earth elements are added to the crucible electric furnace for smelting.

[0025] Among them, rare earth elements are a kind of MSG-like additives. As an additive for lead-acid battery grid alloys, they are beneficial to the mechanical properties, corrosion resistance, casting properties and conductivity of the grid alloys. The rare earth elements added in this embodiment are lanthanum (La), samarium (Sm), cerium (Ce) and yttrium (y).

[0026] During the smelting process, the temperature is controlled between 600 and 1000°C; at this time, a stirring device is provided to fully stir the rare earth elements to ensure uniform mixing.

[0027] Since different rare earth elements have different melting points, in the smelting process, it is very important to properly adjust the heating rate to ensure the full alloying of rare earth elements. The adjustment of the heating rate can control the melting time of metals at different temperatures, so that low melting point metals and high melting point metals can gradually melt within their respective suitable temperature ranges, avoiding the unevenness of the alloy caused by too fast or too slow heating. In addition, the intelligent adjustment of the heating rate can promote their mixing and diffusion while ensuring that each metal element is fully melted, further improving the uniformity and performance of the alloy. First, the melting temperature at each moment in the smelting process is collected: in this embodiment, a high temperature resistant infrared probe is placed on the top of the crucible electric furnace, and a thermal imaging image of the crucible electric furnace at each moment is obtained, and the melting temperature of the rare earth alloy liquid at each collection point in the thermal imaging image is obtained, and the melting temperature matrix at each collection moment is obtained. The high temperature resistant infrared probe collects the melting temperature every 1min, and the implementer can adjust the collection time interval by himself. It should be understood that each element in the melting temperature matrix represents the melting temperature at each collection point in the area measured by the high temperature resistant infrared probe.

[0028] The mean of all elements in the melting temperature matrix at each collection moment is taken as the average temperature of the rare earth alloy liquid at each collection moment; and the heating rate of melting at each collection moment is calculated through the change of the average temperature at each collection moment and the time interval during the melting process, wherein the calculation of the heating rate is a well-known technology and the specific process is not repeated here.

[0029] Step 2: Analyze the horizontal and vertical temperature change distribution characteristics in the melting temperature matrix at each acquisition time to obtain all melting feature vectors at each acquisition time; based on the difference between each element and the remaining elements in each melting feature vector at each acquisition time, obtain the melting uniformity of each element to form each uniform feature vector at each acquisition time.

[0030] During the smelting process of rare earth elements, due to the different suitable smelting temperatures of different rare earth elements, the smelting temperatures at the same rare earth element position are relatively similar, while the smelting temperatures at different rare earth element positions are less similar. If the rare earth elements are not fully mixed during the smelting process, it may cause large temperature changes in different areas, making it impossible to ensure that the elements can be evenly melted and fully fused, affecting the overall uniformity and performance of the alloy. Therefore, it is more necessary to control and adjust the heating rate during the smelting process of rare earth elements to ensure that the rare earth elements in the alloy liquid are fully melted together.

[0031] In order to ensure that the rare earth elements can be fully mixed and melted in the crucible electric furnace, the first-order difference vector of each row vector in the melting temperature matrix at each acquisition moment is obtained, and the absolute value of all elements in the first-order difference vector is calculated to obtain each transverse temperature difference change vector at each acquisition moment. The transverse temperature difference change vector reflects the change of the transverse temperature difference in the crucible electric furnace. If the inconsistency feature of the temperature difference in the transverse temperature difference change vector is more significant, the feature representing the full mixing and melting of the rare earth elements in the transverse direction of the corresponding position is smaller, and the heating rate in the melting process needs to be appropriately adjusted to improve the melting effect of the rare earth elements.

[0032] Since the calculation of permutation entropy is insensitive to noise and can accurately reflect the inconsistency characteristics of the temperature difference within the transverse temperature difference change vector, the permutation entropy of each transverse temperature difference change vector at each acquisition moment is calculated to describe the chaotic characteristics of the transverse temperature difference at the corresponding position, which can more clearly reflect the mixing and smelting characteristics of the alloy liquid in the crucible electric furnace. The permutation entropy of the transverse temperature difference change vector reflects the complexity and dynamic behavior characteristics of the transverse temperature difference at the corresponding position during the smelting process. The larger the permutation entropy of the transverse temperature difference change vector, the greater the chaotic characteristics of the temperature difference within the transverse temperature difference change vector, which indicates that the mixing and smelting effect of the rare earth elements in the transverse direction of the corresponding position is worse.

[0033] The permutation entropies of all transverse temperature difference change vectors at each acquisition moment are arranged according to the arrangement of row vectors in the matrix, and the arrangement results are recorded as the longitudinal melting characteristic vectors in the crucible furnace at each acquisition moment. The longitudinal melting characteristic vectors reflect the changes in the longitudinal melting characteristics of the alloy liquid in the crucible furnace.

[0034] Since the smelting speed of rare earth elements will be increased by a stirring device during the smelting process of rare earth elements, and when the rare earth elements in the crucible electric furnace are not fully melted, the smelting characteristics at the stirring center position and the stirring edge position will be quite different. Therefore, when the rare earth elements in the crucible electric furnace are not fully melted, the elements in the longitudinal smelting characteristic vector of the crucible electric furnace at each collection moment will show great changes. The greater the change of elements in the longitudinal smelting characteristic vector, the worse the uniformity of the longitudinal smelting of rare earth elements in the crucible electric furnace.

[0035] Therefore, the longitudinal melting uniformity of each element in the longitudinal melting feature vector at each acquisition moment is calculated: , where is the longitudinal melting uniformity of the jth element in the longitudinal melting feature vector at the tth acquisition moment, is an exponential function with a natural constant as base, is the number of elements in the longitudinal melting feature vector at the tth acquisition moment, , They are the jth and vth elements in the longitudinal smelting feature vector at the tth acquisition moment, respectively. It should be understood that if the rare earth elements in the crucible electric furnace are not fully smelted, the elements in the longitudinal smelting feature vector in the crucible electric furnace at each acquisition moment will change greatly, and the uniformity of the longitudinal smelting in the crucible electric furnace will be poor, and the longitudinal smelting uniformity will be smaller.

[0036] The transverse melting characteristic vector in the crucible electric furnace at each collection moment is extracted from each column vector in the melting temperature matrix at each collection moment in the same way as the longitudinal melting characteristic vector; the transverse melting characteristic vector in the crucible electric furnace at each collection moment is calculated in the same way as the longitudinal melting uniformity to obtain the transverse melting uniformity of each element in the transverse melting characteristic vector at each collection moment. The smaller the transverse melting uniformity, the worse the uniformity of transverse melting when the crucible electric furnace is used to melt rare earth elements.

[0037] The vector composed of the longitudinal melting uniformity corresponding to all elements in the longitudinal melting characteristic vector of the crucible electric furnace at each acquisition moment is recorded as the longitudinal uniform characteristic vector of the crucible electric furnace at each acquisition moment; the vector composed of the transverse melting uniformity corresponding to all elements in the transverse melting characteristic vector of the crucible electric furnace at each acquisition moment is recorded as the transverse uniform characteristic vector of the crucible electric furnace at each acquisition moment. The longitudinal uniform characteristic vector and the transverse uniform characteristic vector respectively reflect the uniformity characteristics of rare earth element smelting in different directions in the crucible electric furnace. The greater the difference between the two, the greater the difference in the smelting uniformity characteristics of rare earth elements in different directions, that is, the greater the overall non-uniformity of rare earth element smelting in the crucible electric furnace, the worse the effect of smelting rare earth elements in the crucible electric furnace at this time.

[0038] It should be noted that the transverse melting characteristic vector and the longitudinal melting characteristic vector are collectively referred to as the melting characteristic vector; the transverse melting uniformity and the longitudinal melting uniformity are collectively referred to as the melting uniformity; and the longitudinal uniform characteristic vector and the transverse uniform characteristic vector are collectively referred to as the uniform characteristic vector.

[0039] Step 3: According to the difference between the uniform characteristic vectors at each collection time, combined with the element distribution characteristics of the uniform characteristic vectors, the smelting effectiveness at each collection time is obtained, and the heating rate of the crucible electric furnace at each collection time is adjusted; after the smelting is completed, the rare earth alloy liquid is obtained, and the intermediate rare earth alloy is prepared by the ingot casting process.

[0040] If the various rare earth elements are not fully melted together during smelting, it will cause large temperature changes in different directions, resulting in large differences in the smelting uniformity characteristics of the rare earth elements in different directions, and it is impossible to ensure that the rare earth elements can be fully mixed and smelted during the smelting process. In order to be able to more accurately control and adjust the heating rate during the smelting process, so as to fully melt the various rare earth elements in the crucible electric furnace together and alloy the various rare earth elements to the greatest extent, further analysis is needed based on the smelting uniformity characteristics in different directions in the crucible electric furnace.

[0041] The longitudinal uniform feature vector and the transverse uniform feature vector during smelting in the crucible electric furnace at each collection moment are aligned so that the lengths of the longitudinal uniform feature vector and the transverse uniform feature vector are the same after alignment. In this embodiment, the alignment is performed based on the first element of the two vectors. The difference vector between the longitudinal uniform feature vector and the transverse uniform feature vector after alignment is calculated, and the average of the absolute values ​​of all elements in the difference vector is recorded as the directional difference during smelting in the crucible electric furnace at each collection moment. The directional difference reflects the overall uniformity characteristics of the rare earth elements during smelting in the crucible electric furnace. The greater the difference between the longitudinal uniform feature vector and the transverse uniform feature vector, the greater the difference between the longitudinal uniform feature vector and the transverse uniform feature vector, indicating that there is a greater difference in the smelting uniformity characteristics of the rare earth elements in different directions during smelting, that is, the greater the overall non-uniformity during smelting of the rare earth elements in the crucible electric furnace, the worse the effect of smelting the rare earth elements in the crucible electric furnace at this time.

[0042] According to the element distribution characteristics in the longitudinal uniform feature vector and the transverse uniform feature vector at each acquisition moment, combined with the directional difference, the smelting utility at each acquisition moment is obtained: the mean of all elements in the longitudinal uniform feature vector at each acquisition moment is recorded as the first mean; the mean of all elements in the transverse uniform feature vector at each acquisition moment is recorded as the second mean; the first mean and the second mean are fused, and fused with the negative correlation mapping result of the directional difference at each acquisition moment, to obtain the smelting utility at each acquisition moment.

[0043] In this embodiment, the first mean is recorded as , and the second mean is recorded as , the directional difference at each acquisition moment is recorded as , the formula of smelting effectiveness at each collection moment is: ;in, It is a preset parameter greater than zero, which is used to prevent the denominator from taking a value of 0. In this embodiment, the value is 0.5.

[0044] It should be understood that if the difference between the smelting uniformity characteristics of rare earth elements in different directions in the crucible electric furnace is smaller, and the smelting uniformity characteristics of rare earth elements in different directions are greater, it means to a certain extent that the smelting effect of rare earth elements in the crucible electric furnace is higher at this time, and the smelting efficiency is greater.

[0045] In the smelting process of rare earth alloys, the smelting efficiency of rare earth elements in the crucible electric furnace is closely related to the heating rate. Specifically, when the smelting efficiency is low, it means that the mixing and smelting of rare earth elements in the electric furnace are not completely uniform. At this time, the heating rate should be increased to speed up the melting process of rare earth elements and ensure that the rare earth elements in the alloy liquid can be fully mixed to avoid the phenomenon of uneven composition. On the other hand, when the smelting efficiency is high, it means that the rare earth elements have been nearly completely melted and mixed. At this time, the heating rate can be reduced to reduce the consumption of electric energy and avoid possible alloy overheating or other adverse reactions caused by too fast heating.

[0046] Based on this, the heating rate of the crucible electric furnace at the next sampling time is adjusted: , where is the heating rate of the crucible electric furnace at the next collection moment; is the heating rate of the crucible electric furnace at the current collection moment; is the smelting efficiency at the current collection time; It is the preset judgment threshold; it is used to judge whether the heating rate is adjusted upward or downward, and the value is 0.5; is the preset maximum adjustment value of the heating rate to avoid the heating rate being too high, which will cause the low melting point metal to melt prematurely and possibly form an uneven alloy before the temperature reaches the melting point of other metals. In this embodiment, the value is 15; Represents an exponential function with a natural constant as base.

[0047] It should be understood that if the smelting efficiency at the current collection moment is low, the heating rate at the next collection moment is increased. Conversely, if the smelting efficiency at the current collection moment is high, the heating rate at the next collection moment is reduced. The rare earth elements are smelted according to the heating rate at the next collection moment to ensure that the rare earth elements in the alloy liquid in the crucible electric furnace are fully melted together, thereby reducing the consumption of electric energy.

[0048] After the rare earth elements are smelted, a rare earth alloy liquid is obtained, and an intermediate rare earth alloy is prepared by using a conventional ingot casting process.

[0049] Step 4: Melt the refined lead in a lead melting pot, add silver and sodium in turn after heating and stir, heat up again and add calcium aluminum alloy, tin and protective agent for smelting, then add the intermediate rare earth alloy and stir to obtain the positive electrode grid rare earth alloy.

[0050] Place refined lead with a purity of at least 99.99% in a lead melting pot, melt it at 450°C to form lead liquid, raise the temperature to 500°C, add silver (Ag) with a purity of at least 99.9% and metallic sodium (Na) from which kerosene has been drained into the lead liquid, and then stir for 5 minutes to obtain alloy liquid 1; In this process, in order to prevent the sodium metal from catching fire when it is added, the present embodiment adds the sodium metal into the lead liquid in small amounts and multiple times, allowing it to melt quickly in the lead to ensure the utilization rate of the sodium.

[0051] The alloy liquid 1 is heated to 590° C., and calcium aluminum alloy, tin with a purity of 99.9% and a protective agent are added in sequence, and then smelted at 650° C. to obtain alloy liquid 2.

[0052] An intermediate rare earth alloy is added to alloy liquid 2. Since a large amount of the intermediate rare earth alloy is added, the temperature drops greatly. In order to ensure that the rare earth elements can be better alloyed, the temperature is required to keep rising. After all the ingredients are added, stir for 20 minutes, then let it stand, remove the slag, take samples, and use the traditional ingot casting process to prepare the positive grid rare earth alloy for lead-acid batteries.

[0053] Among them, the positive electrode grid rare earth alloy preparation process flow chart is as follows Figure 2 shown.

[0054] Example 2 Example 2 of the present application proposes a method for preparing a rare earth alloy for a lead-acid battery, which is applied to the technical field of lead-acid batteries. Figure 1 The method is consistent with the method in Example 1, wherein in step 1, the temperature range for smelting refined lead and rare earth elements in a crucible electric furnace is 600-800°C; in step 4, after heating to 550°C, silver and sodium are added in sequence for stirring; after heating to 600°C again, calcium aluminum alloy, tin and a protective agent are added for smelting, and finally a rare earth alloy for a positive grid of a lead-acid battery is obtained.

[0055] Example 3 Example 3 of the present application proposes a method for preparing a rare earth alloy for a lead-acid battery, which is applied to the technical field of lead-acid batteries. Figure 1The method is consistent with the method in Example 1, wherein in step 1, the temperature range for smelting refined lead and rare earth elements in a crucible electric furnace is 600-900°C; in step 4, after heating to 550°C, silver and sodium are added in sequence for stirring; after heating to 650°C again, calcium aluminum alloy, tin and a protective agent are added for smelting, and finally a positive grid rare earth alloy for a lead-acid battery is obtained.

[0056] The flowchart and block diagram in the accompanying drawings show the possible architecture, function and operation of the system, method and computer program product according to the embodiment of the present application. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of the code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. In some alternative implementations, the function marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two continuous boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. In the description corresponding to the flowchart and the block diagram in the accompanying drawings, the operations or steps corresponding to different boxes can also occur in a different order from the order disclosed in the description, and sometimes there is no specific order between different operations or steps. For example, two continuous operations or steps can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. Each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented by a dedicated hardware-based system that performs the specified functions or actions, or may be implemented by a combination of dedicated hardware and computer instructions.

[0057] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A method for preparing a rare earth alloy for a lead-acid battery, characterized in that: The method includes: Step 1: Smelting refined lead and rare earth elements in a crucible electric furnace; the smelting temperatures of all sampling points in the crucible electric furnace at each sampling moment during the smelting process are combined into a smelting temperature matrix at each sampling moment; Step 2: Analyze the temperature change distribution characteristics in the horizontal and vertical directions in the melting temperature matrix at each acquisition time, and obtain all melting feature vectors at each acquisition time; based on the difference between each element and the other elements in each melting feature vector at each acquisition time, obtain the melting uniformity of each element to form each uniform feature vector at each acquisition time; Step 3: According to the difference between the uniform feature vectors at each collection time, combined with the element distribution characteristics of the uniform feature vector, the smelting effectiveness at each collection time is obtained, and the heating rate of the crucible electric furnace at each collection time is adjusted; after the smelting is completed, the rare earth alloy liquid is obtained, and the intermediate rare earth alloy is prepared by the ingot casting process; Step 4: Melt the refined lead in a lead melting pot, add silver and sodium in turn after heating and stir, heat up again and add calcium aluminum alloy, tin and protective agent for smelting, add the intermediate rare earth alloy and keep heating, stir to obtain the positive electrode grid rare earth alloy.

2. The method for preparing a rare earth alloy for a lead-acid battery according to claim 1, wherein: The rare earth elements are specifically lanthanum, samarium, cerium and yttrium.

3. The method for preparing a rare earth alloy for a lead-acid battery according to claim 1, characterized in that: The temperature range for smelting the refined lead and the rare earth elements in the crucible electric furnace is 600-1000°C.

4. The method for preparing a rare earth alloy for a lead-acid battery according to claim 1, characterized in that: The smelting characteristic vector includes a longitudinal smelting characteristic vector and a transverse smelting characteristic vector, and the acquisition steps are as follows: Obtain the first-order difference vector of each row vector in the melting temperature matrix at each acquisition moment, and calculate the absolute value of all elements in the first-order difference vector to obtain each lateral temperature difference change vector at each acquisition moment; Calculate the permutation entropy of each transverse temperature difference change vector at each acquisition moment, and use the vector composed of the permutation entropy of all transverse temperature difference change vectors at each acquisition moment as the longitudinal melting characteristic vector at each acquisition moment; The same method as the longitudinal melting characteristic vector is used to obtain the transverse melting characteristic vector at each collection moment according to each column vector in the capacity-temperature matrix at each collection moment.

5. The method for preparing a rare earth alloy for a lead-acid battery according to claim 4, characterized in that: The melting uniformity includes the longitudinal melting uniformity and the transverse melting uniformity; the uniform characteristic vector includes the longitudinal uniform characteristic vector and the transverse uniform characteristic vector, which are specifically: For each element in the longitudinal melting characteristic vector, the absolute value of the difference between each element and the remaining elements is obtained, the absolute value of the difference between each element and all the remaining elements is accumulated and then negatively correlated to obtain the longitudinal melting uniformity of each element; the vector composed of the longitudinal melting uniformity of all elements in the longitudinal melting characteristic vector at each acquisition moment is recorded as the longitudinal uniformity characteristic vector at each acquisition moment; The same method as that for the longitudinal smelting uniformity is adopted to obtain the transverse smelting uniformity of the transverse smelting characteristic vector based on the transverse smelting characteristic vector; the vector composed of the transverse smelting uniformity of all elements in the transverse smelting characteristic vector at each acquisition moment is recorded as the transverse uniformity characteristic vector at each acquisition moment.

6. The method for preparing a rare earth alloy for a lead-acid battery according to claim 5, characterized in that: The method of obtaining the smelting utility at each collection time includes: Align the longitudinal uniform feature vector and the transverse uniform feature vector at each acquisition moment, calculate the difference vector between the two vectors, and record the average of the absolute values ​​of all elements in the difference vector as the directional difference at each acquisition moment; The mean of all elements in the longitudinal uniform feature vector at each acquisition moment is recorded as the first mean; the mean of all elements in the transverse uniform feature vector at each acquisition moment is recorded as the second mean; the first mean and the second mean are fused, and then fused with the negative correlation mapping result of the directional difference at each acquisition moment to obtain the smelting utility at each acquisition moment.

7. The method for preparing a rare earth alloy for a lead-acid battery according to claim 1, characterized in that: The calculation method for adjusting the heating rate of the crucible electric furnace at each sampling moment is: , where is the heating rate of the crucible electric furnace at the next sampling moment, is the heating rate of the crucible electric furnace at the current collection time, is the smelting efficiency at the current collection time, is the preset judgment threshold, It is the preset maximum adjustment value of the heating rate. Represents an exponential function with a natural constant as base.

8. The method for preparing a rare earth alloy for a lead-acid battery according to claim 1, characterized in that: After the heating, silver and sodium are added in sequence and stirred, wherein the temperature is raised to 500-550°C.

9. The method for preparing a rare earth alloy for a lead-acid battery according to claim 1, characterized in that: The temperature of the smelting after heating up again and adding calcium aluminum alloy, tin and protective agent is 600-650°C.

10. The method for preparing a rare earth alloy for a lead-acid battery according to claim 1, characterized in that: During the process of adding the intermediate rare earth alloy and stirring, the temperature needs to be kept rising and stirred for 20 minutes.

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