Copper-core terminal post of an energy storage lead-acid battery

Abstract

The present invention belongs to the technical field of energy storage batteries, and particularly relates to a copper-core terminal for an energy storage lead-acid battery, which comprises a copper core and a lead base. The copper core comprises components with the following percentage contents: zinc 10% - 13%, silver 0.008% - 0.01%, and the balance being copper. The lead base comprises components with the following percentage contents: silver 0.005% - 0.008%, calcium 0.5% - 0.65%, tin 1% - 1.3%, zinc 3% - 4%, and the balance being lead. The present invention enables the copper-core terminal with the copper core and the lead base to meet the requirements of the energy storage lead-acid battery for its torsion, conductivity, hardness and corrosion resistance, and ensures the service life of the energy storage lead-acid battery.

Description

Technical Field

[0001] The present invention belongs to the technical field of energy storage batteries, and particularly relates to a copper core terminal post for an energy storage lead-acid battery. Background Art

[0002] Energy storage batteries mainly refer to the batteries used in solar power generation equipment, wind power generation equipment, and for storing energy from renewable energy sources. Due to the large differences in the operating conditions of energy storage batteries, many energy storage batteries are exposed to sunlight or buried deep underground. In such extreme operating conditions, the connection terminals of the energy storage batteries will be severely corroded. At the same time, when the energy storage batteries are in use, there will also be a relatively frequent large current discharge situation. The large current will cause problems such as micro-melting or even fracture inside the battery, especially at the terminal post end. Also, since the service life of energy storage batteries usually needs to last for 5 years or even 7 years to be considered qualified, the stability of the terminal post end is one of the important parameters for measuring the service life of energy storage batteries. Currently, energy storage batteries adopt a structure of a copper core with a lead cladding as the composition method of the terminal post, and silver is plated at the sandwich layer. Because the connection between copper and lead is not very firm, and energy storage batteries are not frequently replaced, the terminal post is a tightly assembled product. Also, because the screw will cause a large torque to the terminal post during installation, it is very easy for the copper layer and the lead layer to have poor contact due to sliding, resulting in an increase in resistance, thus affecting the conductivity and service life of the energy storage battery; in addition, the pure copper core does not have good corrosion resistance, and the thickness of the plating layer is also relatively thin, and usually the corrosion-resistant layer will be worn out within two years.

[0003] There are studies on the service life of the terminal post of energy storage batteries in the prior art. For example, in the patent application CN112072060A, a high-torque corrosion-resistant terminal post forming process, etc., by electroplating a first plating layer of lead-tin alloy on the inner and outer surfaces of the copper core to improve the corrosion resistance of the copper core, solves the problem of poor contact and increased resistance caused by the weak bonding force between the copper core and the lead body. However, the existing copper core terminal posts are only applicable to power batteries. Since the service life of power batteries is usually 1 - 2 years, the power batteries have low torque requirements for the copper core terminal posts. Also, since the service life of energy storage batteries needs to reach 5 - 7 years, the torque requirements of energy storage batteries for the copper core terminal posts are much higher than those of power batteries. Therefore, it can be seen that the existing copper core terminal posts are difficult to meet the requirements of energy storage batteries for their torque, conductivity, hardness, and corrosion resistance. For this reason, a new technical solution is needed to solve the above technical problems. Summary of the Invention

[0004] The purpose of the present invention is to provide a copper core terminal post for an energy storage lead-acid battery to solve the problem proposed in the above background art that the existing copper core terminal posts are only applicable to power batteries and are difficult to meet the requirements of energy storage batteries for their torque, conductivity, hardness, and corrosion resistance, thus affecting the service life of energy storage batteries.

[0005] To achieve the above object, the present invention provides the following technical solution: A copper core terminal post for a storage lead-acid battery, comprising a copper core and a lead base. The copper core comprises components with the following percentage by content: zinc 10% - 13%, silver 0.008% - 0.01%, and the rest is copper. The lead base comprises components with the following percentage by content: silver 0.005% - 0.008%, calcium 0.5% - 0.65%, tin 1% - 1.3%, zinc 3% - 4%, and the rest is lead.

[0006] Further, the copper in the copper core is sheet copper with a purity of ≥99.95%, the silver in the copper core is industrial silver with a purity of ≥99.0%, and the zinc in the copper core is grade-three zinc powder. The copper core is prepared by the following method: First, preheat the alloy furnace and lay a layer of charcoal at its bottom, then add the formulated amount of copper. At the same time, preheat the formulated amounts of zinc and silver on the furnace platform. After the copper is completely melted, skim the slag, and then sequentially add the preheated zinc and silver and stir to obtain a copper core alloy liquid. Then add phosphor bronze for deoxidation to generate phosphorus pentoxide gas which escapes from the copper core alloy liquid, and copper phosphate floats on the liquid surface and is skimmed off. Stir during the deoxidation process. After the stirring ends, skim the slag and take out the furnace to form a deoxidized copper core alloy liquid. Finally, pour the deoxidized copper core alloy liquid into a copper core mold and cool it to prepare the copper core.

[0007] Further, the lead in the lead base is electrolytic lead with a purity of ≥99.994%, the silver in the lead base is industrial silver with a purity of ≥99.0%, the calcium in the lead base is electrolytic calcium with a purity of ≥99.0%, the tin in the lead base is refined tin with a purity of ≥99.0%, and the zinc in the lead base is grade-three zinc powder. The lead base is prepared by the following method: Add the formulated amount of lead to the alloy furnace, control the temperature of the alloy furnace, and at the same time add charcoal and stir. After the stirring ends, skim the lead slag. When the temperature of the lead liquid is stable, sequentially put the formulated amounts of zinc and silver into the alloy furnace and stir at a stirring frequency of 20 Hz. Then reduce the stirring frequency to 15 - 18 Hz and sequentially add the formulated amounts of calcium and tin into the alloy furnace and stir. After the stirring ends, cast ingots to obtain lead ingots. Finally, send the lead ingots to the mold section of the lead base to be melted again to obtain lead liquid, and the lead liquid is cooled in the mold of the lead base to prepare the lead base.

[0008] The structure of the copper core terminal post made according to the above preparation process is as follows: A support seat with a cylindrical structure is arranged on the upper part of one end of the lead base. A square groove is opened on the inner side of the middle of the support seat and is fixedly connected with the copper core in an embedded manner through the square groove. The other end of the lead base is connected to the bus bar of the energy storage lead-acid battery; A square seat that fits with the square groove is arranged at the lower part of the copper core. A bite groove is opened at the lower part of the square seat and is fixedly embedded in the square groove through the bite groove; A circular fixing seat is arranged at the upper part of the copper core and is fixed on the top of the support seat through the circular fixing seat; A screw hole is arranged at the central position of the copper core, and a color glue groove is arranged axially at the top of the copper core.

[0009] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0010] 1. The present invention uses an element system of copper + zinc + silver to prepare the copper core, effectively improving the conductivity of the copper core, and at the same time effectively improving the corrosion resistance of the copper core. Then, an element system of lead + calcium + tin + zinc + silver is used to prepare the lead base, making the lead base more compatible with the bus bar of the energy storage lead-acid battery, effectively improving the conductivity of the lead base, and at the same time effectively improving the hardness and corrosion resistance of the lead base. Thus, the copper core terminal post with this copper core and lead base can meet the requirements of the energy storage lead-acid battery for its torque, conductivity, hardness, and corrosion resistance, ensuring the service life of the energy storage lead-acid battery;

[0011] 2. The present invention uses copper alloy as the raw material of the copper core, enabling the copper core to achieve the best strength and hardness. By adding zinc to the copper alloy, the corrosion resistance of the copper core is improved, making it easier to fuse with the lead base, and at the same time effectively reducing the production cost. By adding silver to the copper alloy, the conductivity of the copper core is effectively improved, effectively avoiding the process of silver plating the copper core. Thus, the copper core can meet the requirements of the energy storage lead-acid battery for its torque, conductivity, hardness, and corrosion resistance, ensuring the service life of the energy storage lead-acid battery;

[0012] 3. The present invention uses lead-tin series alloy as the raw material of the lead base, making the lead base more compatible with the bus bar of the energy storage lead-acid battery. By adding calcium to the lead-tin series alloy, the hardness and strength of the lead base are effectively improved. By adding silver to the lead-tin series alloy, the conductivity of the lead base is effectively improved. By adding zinc to the lead-tin series alloy, the corrosion resistance of the lead base is effectively improved. Thus, the lead base can meet the requirements of the energy storage lead-acid battery for its torque, conductivity, hardness, and corrosion resistance, ensuring the service life of the energy storage lead-acid battery;

[0013] 4. In the present invention, the copper core is fixed to the upper part of one end of the lead base by the engagement groove being embedded in the square groove, enabling the copper core and the lead base to maintain firmness both horizontally and longitudinally, ensuring the torque of the copper core pole column, effectively avoiding the problem of sliding between the copper core and the lead base due to excessive torque, solving the problem of poor contact resulting in increased resistance, and thus ensuring the electrical conductivity and service life of the energy storage lead-acid battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a schematic diagram of the overall structure of the copper core pole column of the present invention;

[0015] Figure 2 is a schematic diagram of the structure of the copper core of the present invention;

[0016] Figure 3 is a schematic diagram of the structure of the lead base of the present invention.

[0017] Wherein: 1, copper core; 2, lead base; 3, support base; 4, square groove; 5, square seat; 6, engagement groove; 7, circular fixing seat; 8, screw hole; 9, color glue groove. DETAILED DESCRIPTION OF THE INVENTION

[0018] The following examples are used to further illustrate the content of the present invention and do not limit the application of the present invention. Example 1:

[0019] First, select silver with a content of 0.0082%, zinc with a content of 10.073%, and the balance being copper as the raw material components of the copper core 1. Among them, the copper is sheet copper with a purity ≥ 99.95%, the silver is industrial silver with a purity ≥ 99.0%, and the zinc is tertiary zinc powder; then select silver with a content of 0.0053%, calcium with a content of 0.517%, tin with a content of 1.051%, zinc with a content of 3.025%, and the balance being lead as the raw material components of the lead base 2. Among them, the lead is electrolytic lead with a purity ≥ 99.994%, the silver is industrial silver with a purity ≥ 99.0%, the calcium is electrolytic calcium with a purity ≥ 99.0%, the tin is refined tin with a purity ≥ 99.0%, and the zinc is tertiary zinc powder;

[0020] Next, prepare the copper core 1 according to the selected copper core components above. The specific preparation method of the copper core 1 is as follows: First, preheat the alloy furnace to dark red, lay a layer of dry charcoal with a thickness of 30 - 50 cm at the bottom of the furnace, then add sheet copper with a purity ≥ 99.95%, and raise the temperature of the alloy furnace to 1200 - 1220 °C to completely melt the sheet copper. At the same time, tertiary zinc powder with a content of 10.073% and industrial silver with a content of 0.0082% and a purity ≥ 99.0% are placed on the furnace platform of the alloy furnace for preheating, and it is ensured that the tertiary zinc powder and industrial silver can enter the alloy furnace as hot materials. During the melting process of the sheet copper, the sheet copper also needs to be stirred to prevent bridging. After the sheet copper is completely melted, slag is skimmed at a stirring speed of 5 Hz. Then, the preheated tertiary zinc powder and industrial silver are added to the alloy furnace in sequence and stirred at a speed of 15 - 18 Hz for 30 minutes to obtain a copper core alloy liquid. Then, 0.3 - 0.4% of phosphor copper based on the weight of the copper core alloy liquid is added for deoxidation, generating phosphorus pentoxide gas that escapes from the copper core alloy liquid, and copper phosphate floats on the liquid surface and is skimmed off to achieve the purpose of deoxidation. During the deoxidation process, stirring is also required for more than 30 minutes. After the stirring speed drops to 5 Hz, slag is skimmed and the furnace is tapped to form a deoxidized copper core alloy liquid. At this time, the casting temperature of the deoxidized copper core alloy liquid is 1100 - 1200 °C. Finally, the deoxidized copper core alloy liquid is poured into a copper core mold and cooled to prepare the copper core 1.

[0021] Next, prepare the lead base 2 according to the selected lead base 2 components above. The specific preparation method of the lead base 2 is as follows: Add electrolytic lead with a purity ≥ 99.994% to the alloy furnace, and control the temperature of the alloy furnace at 800 °C. When the furnace temperature rises to 550 °C, set the temperature to 600 °C, and at the same time add charcoal and stir at a stirring frequency of 25 Hz for 10 minutes, then skim the lead slag. When the lead liquid stabilizes at 600 °C, add tertiary zinc powder with a content of 3.025% to the alloy furnace and stir at a stirring frequency of 20 Hz for 20 minutes. Then, add industrial silver with a content of 0.0053% and a purity ≥ 99.0% to the alloy furnace and stir at a stirring frequency of 20 Hz for 10 minutes. Then, after reducing the stirring frequency to 15 - 18 Hz, add electrolytic calcium with a content of 0.517% and a purity ≥ 99.0% to the alloy furnace and stir for 15 minutes. Then, add refined tin with a content of 1.051% and a purity ≥ 99.0% to the alloy furnace and stir for 25 minutes while keeping the stirring frequency unchanged to obtain an ingot. Finally, send the ingot to the mold section of the lead base to be remelted to obtain lead liquid, and the lead liquid is cooled in the mold of the lead base to prepare the lead base 2.

[0022] Next, combine the prepared copper core 1 and the lead base 2 to form the copper core terminal of the energy storage lead-acid battery. For the specific copper core terminal, refer to Figures 1 - 3, a support base 3 with a cylindrical structure is provided at the upper part of one end of the lead base 2. A square groove 4 is opened on the inner side of the middle of the support base 3 and is fixedly connected to the copper core 1 in an embedded manner through the square groove 4. The other end of the lead base 2 is connected to the bus bar of the energy storage lead-acid battery (the functions and structures of conventional devices such as bus bars are well-known in the art, and the connection settings are also common knowledge, so no further description will be given here and it is not shown in the drawings); a square seat 5 that fits with the square groove 4 is provided at the lower part of the copper core 1. A bite groove 6 is opened at the lower part of the square seat 5 and is fixedly embedded in the square groove 4 through the bite groove 6; a circular fixing seat 7 is provided at the upper part of the copper core 1 and is fixed to the top of the support base 3 through the circular fixing seat 7; a screw hole 8 is provided at the central position of the copper core 1, and a color glue groove 9 is provided axially at the top of the copper core 1. Among them, the copper core 1 has an upper-round and lower-square structure and is embedded in the square groove 4 on the support base 3 of the lead base 2, effectively avoiding the problem of sliding between the copper core and the lead base due to excessive torque, solving the problem of increased resistance caused by poor contact, and the bite groove 6 is cast with the copper core 1 first, and then the copper core 1 is placed in the mold of the lead base 2 and the lead liquid flows in, so that the lead liquid automatically flows into the bite groove 6 to ensure that the copper core 1 and the lead base 2 do not slide up and down, and the size of the screw hole can be changed according to requirements for the wiring of the energy storage lead-acid battery, and color glue can be poured into the color glue groove 9 to be used for distinguishing the positive and negative poles. Example 2:

[0023] In this embodiment, the raw material components and their preparation methods of the copper core 1 and the lead base 2 are the same as those in Example 1, only the formula amounts are different, that is: first, silver with a content of 0.0097%, zinc with a content of 12.973%, and the balance being copper are selected as the raw material components of the copper core 1. Among them, the copper is sheet copper with a purity of ≥99.95%, the silver is industrial silver with a purity of ≥99.0%, and the zinc is tertiary zinc powder; then, silver with a content of 0.0078%, calcium with a content of 0.645%, tin with a content of 1.288%, zinc with a content of 3.975%, and the balance being lead are selected as the raw material components of the lead base 2. Among them, the lead is electrolytic lead with a purity of ≥99.994%, the silver is industrial silver with a purity of ≥99.0%, the calcium is electrolytic calcium with a purity of ≥99.0%, the tin is refined tin with a purity of ≥99.0%, and the zinc is tertiary zinc powder.

[0024] Similarly, the specific structure of the copper core 1 and the lead base 2 in this embodiment combined into the copper core pole of the energy storage lead-acid battery is also the same as that in Example 1. Example 3:

[0025] The raw material components and their preparation methods of the copper core 1 and the lead base 2 in this embodiment are the same as those in Embodiment 1, only the formulation amounts are different, that is: first, select silver with a content of 0.0093%, zinc with a content of 11.779%, and the balance being copper as the raw material components of the copper core 1. Among them, the copper is sheet copper with a purity of ≥99.95%, the silver is industrial silver with a purity of ≥99.0%, and the zinc is third-grade zinc powder; then select silver with a content of 0.0069%, calcium with a content of 0.583%, tin with a content of 1.174%, zinc with a content of 3.590%, and the balance being lead as the raw material components of the lead base 2. Among them, the lead is electrolytic lead with a purity of ≥99.994%, the silver is industrial silver with a purity of ≥99.0%, the calcium is electrolytic calcium with a purity of ≥99.0%, the tin is refined tin with a purity of ≥99.0%, and the zinc is third-grade zinc powder.

[0026] Similarly, the specific structure of the copper core pole of the energy storage lead-acid battery formed by the copper core 1 and the lead base 2 in this embodiment is also the same as that in Embodiment 1.

[0027] In order to make the copper core pole meet the performance requirements of the energy storage lead-acid battery, the copper core poles prepared in Embodiments 1-3 were subjected to laboratory tests. The test results show that the copper core poles prepared in Embodiments 1-3 all meet the performance requirements of the energy storage lead-acid battery. The test method is as follows: Step 1: Place the copper core pole in dilute sulfuric acid with a density of 1.25 g / mL, and the liquid level slightly submerges the uppermost part of the lead base 2. Apply a current of 10 A for 4 hours, and the weight change of the copper core pole ≤ 5%; Step 2: Place the copper core pole on fine sand and apply a large current of 80 A for 5 minutes, and the copper core pole has no deformation; Step 3: Place the copper core pole on a torque detection table and use a standard screw to detect. Detect with a torque of 35 N / m, and the copper core pole has no deformation and no slippage.

Claims

1. A copper-core terminal post of a energy storage lead-acid battery, comprising a copper core and a lead base, characterized in that, The copper core comprises components with the following percentage by content: zinc 10%-13%, silver 0.008%-0.01%, and the balance being copper; The copper core is prepared by the following method: preheat the alloy furnace and lay a layer of charcoal at the bottom thereof, then add the formulated amount of copper. At the same time, preheat the formulated amounts of zinc and silver on the furnace platform. After the copper is completely melted, skim the slag, and then successively add the preheated zinc and silver and stir to obtain a copper core alloy liquid. Then add phosphor bronze for deoxidation to generate phosphorus pentoxide gas which escapes from the copper core alloy liquid, and cupric phosphate floats on the liquid surface and is skimmed off. Stir during the deoxidation process. After the stirring ends, skim the slag and pour out of the furnace to form a deoxidized copper core alloy liquid. Finally, inject the deoxidized copper core alloy liquid into a copper core mold and cool to prepare the copper core; The lead base comprises components with the following percentage by content: silver 0.005%-0.008%, calcium 0.5%-0.65%, tin 1%-1.3%, zinc 3%-4%, and the balance being lead; The lead base is prepared by the following method: add the formulated amount of lead into the alloy furnace, control the temperature of the alloy furnace, and at the same time add charcoal and stir. After the stirring ends, skim the lead slag. When the temperature of the lead liquid is stable, successively put the formulated amounts of zinc and silver into the alloy furnace and stir at a stirring frequency of 20 Hz. Then reduce the stirring frequency to 15-18 Hz and successively add the formulated amounts of calcium and tin into the alloy furnace and stir. After the stirring ends, cast ingots to obtain lead ingots. Finally, send the lead ingots to the mold section of the lead base to be melted again to obtain lead liquid, and the lead liquid is cooled in the mold of the lead base to prepare the lead base.

2. The copper core terminal of a lead-acid energy storage battery according to claim 1, characterized in that, The copper in the copper core is sheet copper with a purity of ≥99.95%, the silver in the copper core is industrial silver with a purity of ≥99.0%, and the zinc in the copper core is tertiary zinc powder.

3. The copper core terminal post of a lead-acid energy storage battery according to claim 1, characterized in that, The lead in the lead base is electrolytic lead with a purity of ≥99.994%, the silver in the lead base is industrial silver with a purity of ≥99.0%, the calcium in the lead base is electrolytic calcium with a purity of ≥99.0%, the tin in the lead base is refined tin with a purity of ≥99.0%, and the zinc in the lead base is tertiary zinc powder.

4. A copper core terminal post of a energy storage lead-acid battery according to any one of claims 1-3, characterized in that, At the upper part of one end of the lead base, there is a support seat in a cylindrical structure. A square groove is opened on the inner side of the middle of the support seat and is fixedly connected with the copper core in an embedded manner through the square groove. The other end of the lead base is connected to the bus bar of the energy storage lead-acid battery.

5. The copper core terminal post of an energy storage lead-acid battery according to claim 4, characterized in that, At the lower part of the copper core, there is a square seat that fits with the square groove. A bite groove is opened at the lower part of the square seat and is embedded and fixed in the square groove through the bite groove.

6. The copper core terminal of a lead-acid energy storage battery according to claim 4, characterized in that, At the upper part of the copper core, there is a circular fixing seat and it is fixed to the top of the support seat through the circular fixing seat.

7. The copper core terminal post of a lead-acid energy storage battery according to claim 4, characterized in that, A screw hole is arranged at the central position of the copper core, and a color glue groove is arranged axially at the top of the copper core.

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