Method for recycling and reusing the pole copper core of a power battery

Abstract

The present invention belongs to the technical field of recycling methods for battery components, and specifically relates to a method for recycling and reusing the copper cores of the pole columns of power batteries. The method for recycling and reusing the copper cores of the pole columns of power batteries includes the following steps: a. Ultrasonically degrease the pole columns of waste power batteries with hot alkali, then immerse them in hot water for ultrasonic cleaning, then wash them with running water, and then blow-dry the pole columns; b. Continue to immerse them in a lead-antimony alloy pot, heat and melt them, and cool to room temperature; c. Immerse the melted pole columns in an electroplating stripping solution to electrolyze out the copper cores of the pole columns, and then first wash the copper cores of the pole columns with running water and then wash them with battery water; d. Immerse the copper cores of the pole columns in a chemical plating stripping solution for soaking, then first wash the copper cores of the pole columns with running water and then wash them with battery water, and finally blow-dry the copper cores of the pole columns. The present invention provides a method for recycling and reusing the copper cores of the pole columns of power batteries, which is simple in operation, fast in stripping speed, environmentally friendly, and has obvious social and environmental benefits.

Description

Technical Field

[0001] The present invention belongs to the technical field of recycling methods for battery components, and particularly relates to a method for recycling and reusing the copper cores of the pole columns of power batteries. Background Art

[0002] For special power lead-acid batteries in power batteries, the copper cores inside the pole columns are made of T2 purple copper. According to different battery models, the weight of a single copper core is in the range of (3 - 6) kg. The copper core structure made of T2 purple copper is complex, and its processing and manufacturing require multiple steps of mechanical processing and chemical surface treatment. The manufacturing cost of a single copper core is very high. At present, all pole columns for special batteries at home and abroad are manufactured by gravity casting technology. During the manufacturing process, due to the complex structure of the pole columns, quality defects such as air bubbles and sand holes are likely to occur inside, and thus, a large number of unqualified products are produced. Therefore, effectively recycling and using the copper cores of pole columns for special power batteries has great economic benefits.

[0003] However, there are many difficulties in the supply and demand of recycling the copper cores of pole columns for special power batteries. Since the composition of the lead alloy outside the pole columns of special power batteries is complex and the thickness is relatively high, using conventional strong alkali solution electrolysis to remove the lead alloy layer is time-consuming and costly, and the removal is not thorough. It is easy to have lead tin and lead antimony remaining on the surface of the pole column copper cores, and the copper cores cannot be recycled and reused. Using conventional hydrochloric acid aqueous solution electrolysis to remove the lead alloy layer is also time-consuming and costly, and the removal is seriously uneven, resulting in the surface of the copper cores being damaged into pits, and the copper cores cannot be recycled and reused either. At present, special power battery enterprises can only discard the unqualified pole columns, resulting in great waste and environmental pollution.

[0004] In order to reduce production costs, achieve environmental protection and recycling, and meet the needs of clean production in the lead-acid battery industry, it is extremely urgent to research a method for recycling and using the copper cores of pole columns for special power batteries according to the characteristics of the entire production process of special power battery manufacturing.

[0005] CN106252743B discloses a process for separating and recycling lead parts, lead grids at low temperature and copper pole columns from waste lead-acid batteries. By performing heat transfer on the lead grids and lead parts, a de-shelling phenomenon occurs, and the lead liquid separates from the passivation layers on the surfaces of the lead grids and lead parts, and the passivation layers form lead slag. The lead slag and copper pole columns float on the molten lead liquid to separate the copper pole columns and the lead liquid. However, this method simply separates the copper pole columns and the lead liquid through heat transfer melting, and cannot remove the firmly bonded lead layer on the surface of the copper pole columns. There is still lead layer residue on the surface of the copper pole columns, and the surface quality of the copper pole columns cannot meet the use requirements. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a method for recycling and reusing the pole copper core of a power battery. The method is simple to operate, has a fast removal speed, and is environmentally friendly. After removal, the surface of the copper core is flat and undamaged and can be used normally. The social and environmental benefits are obvious.

[0007] The method for recycling and reusing the pole copper core of a power battery according to the present invention comprises the following steps:

[0008] a. Immerse the pole of the waste power battery in an alkaline solution for ultrasonic degreasing, then take out the pole and immerse it in hot water for ultrasonic cleaning, take out the pole, clean it with running water, and then blow dry the pole;

[0009] b. Immerse the dried pole into the molten liquid lead-antimony alloy, heat and melt it, and then put the pole into a turnover box and cool it to room temperature;

[0010] c. Immerse the molten pole into an electrochemical deplating solution to electrolyze the pole copper core, then wash the pole copper core with running water first, and then wash the battery with water;

[0011] d. Soak the pole copper core in the chemical deplating solution, then clean it with running water, then with battery water, and finally blow dry it.

[0012] The alkaline solution in step a is a mixed solution of Na2CO3 and Na3PO4·12H2O, the temperature of which is 75-85°C and the density of which is 1.015 g / cm 3 ~1.020g / cm 3 .

[0013] In step b, the heating and melting temperature of the lead-antimony alloy pot is 350-400° C., and the heating and melting time is 30-45 minutes.

[0014] The electrolysis time in step c is 60-75 min.

[0015] The soaking time in step d is 10-20 minutes.

[0016] The formulation of the electrochemically stripping solution in step c is as follows: malic acid (70 - 90) g / L, acetic acid (50 - 80) g / L, lead acetate (60 - 120) g / L, antimony acetate (5 - 15) g / L, stannous chloride (20 - 40) g / L, β-naphthol (0.5 - 3.0) g / L, HJX-2 stabilizer (20 - 30) mL / L. The preparation method is as follows: First, pour the battery water, which is about 1 / 2 of the total volume of the electrochemically stripping solution to be prepared, into a plastic tank. Under stirring, slowly add the formulated amounts of acetic acid and malic acid, stirring while adding. After adding, add lead acetate, antimony acetate, and stannous chloride portion by portion. After all are added, stir well for 30 min. Then add β-naphthol and HJX-2 stabilizer portion by portion, and pour the remaining battery water into the plastic tank. After all are added, stir well for more than 2 h. After analysis and adjustment, it can be used.

[0017] The HJX-2 stabilizer is compounded by mixing two or more of methanesulfonic acid, aminosulfonic acid, fatty acid salts, and polyether polyols.

[0018] The formulation of the chemically stripping solution in step d is as follows: hydrochloric acid (100 - 200) mL / L, hydrogen peroxide (30 - 50) mL / L, sodium tartrate (20 - 40) g / L, sodium dodecyl sulfate (40 - 80) mg / L, alanine (15 - 40) mg / L. The preparation method is as follows: First, pour the battery water, which is about 1 / 2 of the total volume of the chemically stripping solution to be prepared, into a plastic tank. Under stirring, slowly pour the formulated amount of hydrochloric acid solution, and then pour the hydrogen peroxide solution, stirring while adding. After adding, add sodium tartrate, sodium dodecyl sulfate, and alanine portion by portion. Pour the remaining battery water into the plastic tank. After all are added, stir well for more than 2 h. After analysis and adjustment, it can be used.

[0019] The process conditions for electrochemical stripping in step c are: anodic current density (1.5 - 3.0) A / dm 2 , temperature (15 - 35) °C, cathode movement frequency (20 - 40) times / min.

[0020] The process conditions for chemical stripping in step d are: temperature (15 - 35) °C, solution stirring speed (200 - 500) r / min.

[0021] Specifically, the method for recycling and reusing the copper core of the pole column of the power battery includes the following steps:

[0022] a. Immerse the special power pole column in a hot alkali solution for ultrasonic degreasing for 15 min, take out the pole column, immerse it in hot water for ultrasonic cleaning for 5 min, take out the pole column, immerse it in flowing battery water for cleaning for 5 min, and take out the pole column for air drying.

[0023] b. Immerse the dried terminal post into a lead - antimony alloy pot containing liquid - molten lead - antimony alloy at a temperature of 350°C to 400°C, melt for 30 min to 45 min to remove the lead - antimony alloy layer, take out the melted terminal post and place it in a sealed turnover box to cool down to room temperature.

[0024] c. Immerse the melted terminal post into an electro - chemical stripping solution, electrolyze for 60 min to 75 min to remove the lead - antimony alloy layer and lead - tin alloy layer on the surface, expose the copper core of the terminal post. Take out the copper core of the terminal post and immerse it in running tap water for 5 min, then take out the copper core of the terminal post and immerse it in running battery - used water for 5 min; Anodic current density is (1.5 - 3.0) A / dm 2 , temperature is (15 - 35)°C, and the frequency of cathode movement is (20 - 40) times / min.

[0025] The formula of the electro - chemical stripping solution is: malic acid (70 - 90) g / L, acetic acid (50 - 80) g / L, lead acetate (60 - 120) g / L, antimony acetate (5 - 15) g / L, stannous chloride (20 - 40) g / L, β - naphthol (0.5 - 3.0) g / L, HJX - 2 stabilizer (20 - 30) mL / L.

[0026] d. Immerse the copper core of the terminal post into a chemical stripping solution and soak for 10 min to 20 min, temperature is (15 - 35)°C, the stirring speed of the solution is (200 - 500) r / min, remove the remaining lead - tin alloy on the surface of the copper core. Take out the copper core of the terminal post and immerse it in running tap water for 5 min, then take out the copper core of the terminal post and immerse it in running battery - used water for 5 min, and then take out the copper core of the terminal post and dry it with cold air. The formula of the chemical stripping solution is: hydrochloric acid (100 - 200) mL / L, hydrogen peroxide (30 - 50) mL / L, sodium tartrate (20 - 40) g / L, sodium dodecyl sulfate (40 - 80) mg / L, alanine (15 - 40) mg / L.

[0027] For the copper core of the terminal post of the waste power battery in the present invention, electro - chemical stripping and chemical stripping methods are respectively adopted. In electro - chemical stripping, a compound electro - chemical stripping solution is used. Among them, lead acetate, antimony acetate, and stannous chloride are the main salts for lead alloy electrolysis, providing electrolyzed metal lead, antimony, and stannous ions, which has the effect of reducing anodic polarization in the initial stage of electrolysis. Lead acetate alloy is a weak anodic corrosion inhibitor, which has the effects of preventing the hydrolysis of lead acetate and antimony acetate and improving the current efficiency. Malic acid is a metal ion complexing agent for electrolysis, which has the effect of adjusting acidity. β - naphthol can increase cathode polarization, improve the dispersion ability of the electrolyte, and reduce gas evolution. HJX - 2 stabilizer can prevent the oxidation and hydrolysis of divalent lead, trivalent antimony, and divalent tin, and improve the stability of the electrolyte.

[0028] In chemical stripping, a compound chemical stripping solution is used. Hydrochloric acid is used as the chemical etchant for lead-tin alloy to dissolve the lead-tin alloy on the surface of the copper core. Hydrogen peroxide is used as the oxidizer for lead-tin alloy to promote the oxidation of lead ions and stannous ions. Sodium tartrate, sodium dodecyl sulfate, and alanine are used as composite corrosion inhibitors for the copper core of the pole column to prevent over-corrosion on the surface of the copper core.

[0029] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0030] (1) By using the method for recycling and reusing the copper core of the pole column of the power battery of the present invention, there is no lead slag residue and no corrosion pits on the recycled copper core of the pole column. The surface is flat and bright, meeting the quality requirements of the copper core for the manufacture of special power battery pole columns, and the economic benefits are obvious.

[0031] (2) The method for recycling and reusing the copper core of the pole column of the power battery of the present invention is realized by borrowing the alloy pot equipment in the manufacture of special power batteries. The pole column cleaning, electrochemical stripping, and chemical stripping of the lead alloy layer are realized by borrowing the surface treatment equipment for the negative grid in the manufacture of special power batteries. The operation is simple and the production cost is low.

[0032] (3) The method for recycling and reusing the copper core of the pole column of the power battery of the present invention uses an electrochemical stripping solution and a chemical stripping solution in cooperation, with high stability. It can be repeatedly adjusted and used in production. Its main components are non-toxic and non-corrosive, and are environmentally friendly. Description of the Drawings

[0033] Figure 1 It is a schematic flow chart of recycling and reusing the copper core of the pole column of the power battery of the present invention. Detailed Embodiments

[0034] The following further describes the present invention in conjunction with embodiments.

[0035] The reagents used in the following embodiments are all from normal commercially available products.

[0036] Embodiment 1

[0037] The method for recycling and reusing the copper core of the pole column of UPB-I battery includes the following steps:

[0038] a. Use a special fixture to immerse the pole column of UPB-I battery into the hot alkali solution for ultrasonic degreasing for 15 minutes. The power of the ultrasonic cleaner is 1.2 kW, and the working frequency is 25 KHz ± 2 KHz; take out the pole column and immerse it in hot water for ultrasonic cleaning for 5 minutes. The power of the ultrasonic cleaner is 1.5 kW, and the working frequency is 28 KHz ± 2 KHz, and the temperature of the hot water is 65 °C ± 5 °C; take out the pole column and immerse it in flowing battery water for cleaning for 5 minutes, take out the pole column and blow it dry with hot air, and the hot air temperature is 85 °C ± 5 °C. The raw materials of the hot alkali solution are shown in Table 1.

[0039] The special fixture for the terminal post of UPB-I battery has a length of 320 mm, a height of 180 mm, and a width of 90 mm. The fixture has two terminal post fixing clips and an overall weight of 7.5 kg.

[0040] Table 1 Raw materials for hot alkali solution

[0041] Name Content g / L <![CDATA[Sodium carbonate for industrial use Na2CO3 (100%)]]> 50 <![CDATA[Sodium phosphate tribasic dodecahydrate Na3PO4·12H2O(100%)]]> 100

[0042] Preparation method: First, inject the measured amount of tap water into the ultrasonic cleaning tank, then add the weighed industrial sodium carbonate into the tap water, and then add the weighed trisodium phosphate into the sodium carbonate solution. After stirring until it is completely dissolved, it can be used. The density at 80 °C after preparation is: 1.017 g / cm 3 .

[0043] b. Use a special tooling to seal the connection hole of the terminal post of the UPB-I battery. Immerse the dried terminal post into a lead-antimony alloy pot at a temperature of 375 °C. During the operation, slowly immerse the lead layer of the terminal post completely into the molten alloy liquid. After melting for 35 minutes to remove the lead-antimony alloy layer, take out the melted terminal post, gently shake off the excess lead liquid on the surface, and put it into a sealed turnover box and cool it to room temperature.

[0044] c. Immerse the melted terminal post into the electrochemically stripping solution and electrolyze for 60 minutes to remove the lead-antimony alloy layer and lead-tin alloy layer on the surface, exposing the copper core of the terminal post. Take out the copper core of the terminal post and immerse it in running tap water for 5 minutes, and then take out the copper core of the terminal post and immerse it in running battery water for 5 minutes; the anodic current density is 1.5 A / dm 2 , the temperature is 20 °C, and the cathode moving frequency is 20 times / min. The formula of the electrochemically stripping solution is shown in Table 2.

[0045] Table 2 Formula of electrochemically stripping solution

[0046]

[0047] The preparation method of the electrochemically stripping solution is: First, inject the battery water accounting for 1 / 2 of the total volume of the prepared electrochemically stripping solution into the electrochemically stripping tank. Under stirring, slowly add the measured amount of acetic acid and malic acid in Table 2, adding while stirring. After adding, add the measured amount of lead acetate, antimony acetate, and stannous chloride in Table 2 portion by portion. After all are added, stir well for 30 minutes, and then add the measured amount of β-naphthol and HJX-2 stabilizer in Table 2 portion by portion. Inject the remaining battery water into the stripping tank. After all are added, stir well for more than 2 hours. After analysis and adjustment, it can be used.

[0048] d. Immerse the copper core of the terminal post in the chemical stripping solution for 10 minutes at a temperature of 20°C and a solution stirring speed of 200 r / min to remove the remaining lead-tin alloy on the surface of the copper core. Take out the copper core of the terminal post and immerse it in running tap water for cleaning for 5 minutes. Then take out the copper core of the terminal post and immerse it in running battery water for cleaning for 5 minutes. Finally, take out the copper core of the terminal post and dry it with cold air. The formula of the chemical stripping solution is shown in Table 3.

[0049] Table 3 Formula of the Chemical Stripping Solution

[0050] Name Purity Concentration Industrial synthetic hydrochloric acid 31％ 100 mL / L Industrial hydrogen peroxide 6％ 30 mL / L Sodium tartrate 99％ 20 g / L Sodium dodecyl sulfate 95％ 40 mg / L L-Alanine 99％ 15 mg / L

[0051] The preparation method of the chemical stripping solution is as follows: First, pour battery water accounting for 1 / 2 of the total volume of the prepared chemical stripping solution into the chemical stripping tank. Under stirring, slowly pour in the formulated hydrochloric acid solution, and then pour in the formulated hydrogen peroxide solution, stirring while adding. After adding, add sodium tartrate, sodium dodecyl sulfate, and alanine portion by portion. Then pour the remaining battery water into the stripping tank. After all are added, stir well for more than 2 hours. After analysis and adjustment, it can be used.

[0052] The copper cores of the terminal posts of the recycled UPB-I batteries are tested, and the test results all meet the technical requirements.

[0053] Example 2

[0054] The method for recycling and reusing the copper cores of the terminal posts of UPB-II batteries includes the following steps:

[0055] a. Use a special fixture to immerse the terminal post of the UPB-II battery in a hot alkali solution for ultrasonic degreasing for 15 minutes. The power of the ultrasonic cleaner is 1.2 kW, and the working frequency is 25 KHz ± 2 KHz. Take out the terminal post and immerse it in hot water for ultrasonic cleaning for 5 minutes. The power of the ultrasonic cleaner is 1.5 kW, and the working frequency is 28 KHz ± 2 KHz. The temperature of the hot water is 65°C ± 5°C. Take out the terminal post and immerse it in running battery water for cleaning for 5 minutes. Then take out the terminal post and dry it with hot air. The temperature of the hot air is 85°C ± 5°C. The raw materials of the hot alkali solution are shown in Table 1. The density at 80°C after preparation is: 1.015 g / cm 3 .

[0056] The special fixture for the terminal post of the UPB-II battery is 650 mm in length, 170 mm in height, and 100 mm in width. The fixture has six end post fixing clips, and the overall weight is 13.8 kg.

[0057] b. Use a dedicated tooling to seal the connection holes of the UPB-II battery poles. Immerse the dried poles into a lead-antimony alloy pot at a temperature of 350 °C. During the operation, slowly immerse the lead layer of the poles completely into the molten alloy liquid. Melt for 45 minutes to remove the lead-antimony alloy layer. Take out the melted poles, gently shake off the excess lead liquid on the surface, and place them in a sealed turnover box to cool down to room temperature.

[0058] c. Immerse the melted poles into the electrochemically stripping solution and electrolyze for 75 minutes to remove the lead-antimony alloy layer and lead-tin alloy layer on the surface, exposing the copper cores of the poles. Take out the copper cores of the poles and immerse them in running tap water for 5 minutes, then take out the copper cores of the poles and immerse them in running battery water for 5 minutes; the anodic current density is 3.0 A / dm 2 , the temperature is 22 °C, and the cathode moving frequency is 40 times / min. The formulation of the electrochemically stripping solution is shown in Table 4.

[0059] Table 4 Formulation of the electrochemically stripping solution

[0060]

[0061] The preparation method of the electrochemically stripping solution is the same as that in Example 1.

[0062] d. Immerse the copper cores of the poles into the chemically stripping solution and soak for 15 minutes at a temperature of 25 °C with the solution stirring speed of 400 r / min to remove the remaining lead-tin alloy on the surface of the copper cores. Take out the copper cores of the poles and immerse them in running tap water for 5 minutes, then take out the copper cores of the poles and immerse them in running battery water for 5 minutes, and then take out the copper cores of the poles and dry them with cold air. The formulation of the chemically stripping solution is shown in Table 5.

[0063] Table 5 Formulation of the chemically stripping solution

[0064]

[0065]

[0066] The preparation method of the chemically stripping solution is the same as that in Example 1.

[0067] Detect the copper cores of the recovered UPB-II battery poles, and the detection results all meet the technical requirements.

[0068] Example 3

[0069] The method for recycling and reusing the copper cores of the UPB-III battery poles includes the following steps:

[0070] a. Immerse the terminal post of the UPB-Ⅲ battery into the hot alkali solution using a special fixture and perform ultrasonic degreasing for 15 minutes. The power of the ultrasonic cleaner is 1.2 kW, and the working frequency is 25 KHz ± 2 KHz. Take out the terminal post and immerse it in hot water for ultrasonic cleaning for 5 minutes. The power of the ultrasonic cleaner is 1.5 kW, the working frequency is 28 KHz ± 2 KHz, and the temperature of the hot water is 65℃ ± 5℃. Take out the terminal post and immerse it in flowing battery water for cleaning for 5 minutes. Take out the terminal post and blow-dry it with hot air, and the hot air temperature is 85℃ ± 5℃. The raw materials of the hot alkali solution are shown in Table 1, and the density at 80℃ after preparation is: 1.020 g / cm 3 .

[0071] The special fixture for the terminal post of the UPB-Ⅲ battery has a length of 650 mm, a height of 170 mm, and a width of 90 mm. The fixture has six terminal post fixing clips, and the overall weight is 11.3 kg.

[0072] b. Use a special tooling to seal the connection hole of the terminal post of the UPB-Ⅲ battery. Immerse the dried terminal post into a lead-antimony alloy pot at a temperature of 400℃. During the operation, slowly immerse the lead layer of the terminal post completely into the molten alloy liquid, and melt for 30 minutes to remove the lead-antimony alloy layer. Take out the melted terminal post, gently shake off the excess lead liquid on the surface, and place it in a closed turnover box to cool down to room temperature.

[0073] c. Immerse the melted terminal post into the electro-chemical stripping solution and electrolyze for 65 minutes to remove the lead-antimony alloy layer and the lead-tin alloy layer on the surface, exposing the copper core of the terminal post. Take out the copper core of the terminal post and immerse it in flowing tap water for cleaning for 5 minutes. Take out the copper core of the terminal post and immerse it in flowing battery water for cleaning for 5 minutes; the anodic current density is 2.0 A / dm 2 , the temperature is 20℃, and the cathode moving frequency is 25 times / min. The formula of the electro-chemical stripping solution is shown in Table 6.

[0074] Table 6 Formula of the electro-chemical stripping solution

[0075]

[0076] The preparation method of the electro-chemical stripping solution is the same as that in Example 1.

[0077] d. Immerse the copper core of the terminal post into the chemical stripping solution and soak for 20 minutes, at a temperature of 25℃, and the solution stirring speed is 300 r / min to remove the remaining lead-tin alloy on the surface of the copper core. Take out the copper core of the terminal post and immerse it in flowing tap water for cleaning for 5 minutes. Take out the copper core of the terminal post and immerse it in flowing battery water for cleaning for 5 minutes. Take out the copper core of the terminal post and dry it with cold air. The formula of the chemical stripping solution is shown in Table 7.

[0078] Table 7 Formula of the chemical stripping solution

[0079] Name Purity Concentration Industrial synthetic hydrochloric acid 31％ 150 mL / L Industrial hydrogen peroxide 6％ 30 mL / L Sodium tartrate 99％ 25 g / L Sodium dodecyl sulfate 95％ 70 mg / L L-Alanine 99％ 25 mg / L

[0080] The preparation method of the chemical stripping solution is the same as that in Example 1.

[0081] The pole column copper cores of the recycled UPB-III batteries are tested, and the test results all meet the technical requirements.

[0082] Example 4

[0083] A method for recycling and reusing the pole column copper cores of UPB-IV batteries includes the following steps:

[0084] a. Immerse the pole columns for UPB-IV batteries in a hot alkali solution using a special fixture and perform ultrasonic degreasing for 15 minutes. The power of the ultrasonic cleaning machine is 1.2 kW, and the working frequency is 25 KHz ± 2 KHz; take out the pole columns and immerse them in hot water for ultrasonic cleaning for 5 minutes. The power of the ultrasonic cleaning machine is 1.5 kW, the working frequency is 28 KHz ± 2 KHz, and the hot water temperature is 65 °C ± 5 °C; take out the pole columns and immerse them in flowing battery water for cleaning for 5 minutes, then take out the pole columns and blow them dry with hot air. The hot air temperature is 85 °C ± 5 °C. The raw materials of the hot alkali solution are shown in Table 1, and the density at 80 °C after preparation is: 1.018 g / cm 3 .

[0085] The special fixture for the pole columns of UPB-IV batteries is 500 mm in length, 190 mm in height, and 100 mm in width. The fixture has four end post fixing clips, and the overall weight is 10.6 kg.

[0086] b. Use a special tooling to seal the connection holes of the pole columns for UPB-IV batteries. Immerse the dried pole columns in a lead-antimony alloy pot at a temperature of 360 °C. During the operation, slowly immerse the lead layer of the pole columns completely into the molten alloy liquid, and melt for 45 minutes to remove the lead-antimony alloy layer. Take out the melted pole columns, gently shake off the excess lead liquid on the surface, and place them in a sealed turnover box to cool down to room temperature.

[0087] c. Immerse the melted pole columns in an electrochemical stripping solution and electrolyze for 70 minutes to remove the lead-antimony alloy layer and lead-tin alloy layer on the surface, exposing the pole column copper cores. Take out the pole column copper cores and immerse them in flowing tap water for cleaning for 5 minutes, then take out the pole column copper cores and immerse them in flowing battery water for cleaning for 5 minutes; the anodic current density is 2.5 A / dm 2 , the temperature is 20 °C, and the cathode movement frequency is 35 times / min. The formula of the electrochemical stripping solution is shown in Table 8.

[0088] Table 8 Formula of the electrochemical stripping solution

[0089]

[0090]

[0091] The preparation method of the electrochemistry stripping solution is the same as that of Example 1.

[0092] d. Immerse the copper core of the terminal post into the chemical stripping solution for 17 min at a temperature of 25 °C and a solution stirring speed of 400 r / min to remove the remaining lead-tin alloy on the surface of the copper core. Take out the copper core of the terminal post and immerse it in running tap water for cleaning for 5 min, then take out the copper core of the terminal post and immerse it in running battery water for cleaning for 5 min, and then take out the copper core of the terminal post and dry it with cold air. The formula of the chemical stripping solution is shown in Table 9.

[0093] Table 9 Formula of the chemical stripping solution

[0094] Name Purity Concentration Industrial synthetic hydrochloric acid 31％ 125 mL / L Industrial hydrogen peroxide 6％ 40 mL / L Sodium tartrate 99％ 35 g / L Sodium dodecyl sulfate 95％ 50 mg / L L-Alanine 99％ 30 mg / L

[0095] The preparation method of the chemical stripping solution is the same as that of Example 1.

[0096] The copper cores of the terminal posts of the recycled UPB-IV batteries are detected, and the detection results all meet the technical requirements.

[0097] Example 5

[0098] A method for recycling and reusing the copper cores of the terminal posts of 5X batteries, comprising the following steps:

[0099] a. Use a special fixture to immerse the terminal post of the 5X battery into a hot alkali solution for ultrasonic degreasing for 15 min. The power of the ultrasonic cleaner is 1.2 kW, and the working frequency is 25 KHz ± 2 KHz; take out the terminal post and immerse it in hot water for ultrasonic cleaning for 5 min. The power of the ultrasonic cleaner is 1.5 kW, and the working frequency is 28 KHz ± 2 KHz, and the temperature of the hot water is 65 °C ± 5 °C; take out the terminal post and immerse it in running battery water for cleaning for 5 min, and then take out the terminal post and dry it with hot air. The raw materials of the hot alkali solution are shown in Table 1, and the density at 80 °C after preparation is: 1.017 g / cm 3 .

[0100] The special fixture for the terminal post of the 5X battery is 410 mm in length, 200 mm in height, and 100 mm in width. The fixture has four end post fixing clips, and the overall weight is 9.4 kg.

[0101] b. Use a special tooling to seal the connection hole of the terminal post of the 5X battery. Immerse the dried terminal post into a lead-antimony alloy pot at a temperature of 390 °C. During the operation, slowly immerse the lead layer of the terminal post completely into the molten alloy liquid. Melt for 35 min to remove the lead-antimony alloy layer. Take out the melted terminal post, gently shake off the excess lead liquid on the surface, and put it into a sealed turnover box to cool to room temperature.

[0102] c. Immerse the melted terminal post into the electrochemically stripping solution, electrolyze for 70 min to remove the lead-antimony alloy layer and lead-tin alloy layer on the surface, expose the copper core of the terminal post, take out the copper core of the terminal post and immerse it in running tap water for cleaning for 5 min, and then take out the copper core of the terminal post and immerse it in running battery water for cleaning for 5 min; the anodic current density is 3.0 A / dm 2 , the temperature is 20 °C, and the cathode moving frequency is 20 times / min. The formulation of the electrochemically stripping solution is shown in Table 10.

[0103] Table 10 Formulation of the electrochemically stripping solution

[0104]

[0105] The preparation method of the electrochemically stripping solution is the same as that in Example 1.

[0106] d. Immerse the copper core of the terminal post in the chemically stripping solution for soaking for 13 min, the temperature is 25 °C, and the solution stirring speed is 350 r / min to remove the remaining lead-tin alloy on the surface of the copper core. Take out the copper core of the terminal post and immerse it in running tap water for cleaning for 5 min, then take out the copper core of the terminal post and immerse it in running battery water for cleaning for 5 min, and then take out the copper core of the terminal post and dry it with cold air. The formulation of the chemically stripping solution is shown in Table 11.

[0107] Table 11 Formulation of the chemically stripping solution

[0108] Name Purity Concentration Industrial synthetic hydrochloric acid 31％ 180 mL / L Industrial hydrogen peroxide 6％ 35 mL / L Sodium tartrate 99％ 20 g / L Sodium dodecyl sulfate 95％ 45 mg / L L-Alanine 99％ 20 mg / L

[0109] The preparation method of the chemically stripping solution is the same as that in Example 1.

[0110] The recovered copper cores of the terminal posts for 5X batteries are detected, and the detection results all meet the technical requirements.

[0111] The detection of the copper core of the terminal post is based on the enterprise standard, and the standard number is Q / ZN J03·067·4-2020. The specific requirements are as follows:

[0112] 1) Appearance quality requirements of the copper core of the terminal post: The surface of the copper core is uniform and smooth, and there shall be no depression greater than 1 mm; there shall be no defects such as slag inclusion, air hole, crack and weld bead on the surface.

[0113] 2) Weight: The weight of the copper core of the terminal post for UPB-I battery is (4.3 ± 0.2) kg, the weight of the copper core of the terminal post for UPB-II battery is (5.7 ± 0.3) kg, the weight of the copper core of the terminal post for UPB-III battery is (4.0 ± 0.2) kg, the weight of the copper core of the terminal post for UPB-IV battery is (3.7 ± 0.2) kg, and the weight of the copper core of the terminal post for 5X battery is (3.5 ± 0.1) kg.

[0114] 3) Air tightness: When the copper core body is passed with compressed air at a pressure of (0.5 ± 0.1) MPa and there is no air leakage within 1 min, it is qualified;

[0115] 4) Permeability: Water is passed through the water-cooling pipe orifice at one end of the copper core body, and the water flow is smooth at the orifice at the other end, which is qualified.

[0116] For the method for recycling and reusing the pole column copper cores of the power battery according to the present invention above, the recycled battery pole column copper cores are detected according to the above standards, and the detection results are shown in Table 12. Parallel three-group experiments are carried out for the weight, height and pole column spacing.

[0117] Table 12 Detection Results

[0118]

[0119] It can be seen from the above that by using the method for recycling and reusing the pole column copper cores of the present invention, the appearance quality, weight, permeability, airtightness and external dimensions of the pole column copper cores for various types of batteries meet the technical requirements and can be directly put into production and use.

[0120] Of course, the above content is only a preferred embodiment of the present invention and cannot be considered as limiting the scope of the embodiments of the present invention. The present invention is not limited to the above examples either. Equal changes and improvements made by those of ordinary skill in the art within the essence of the present invention shall fall within the scope covered by the patent of the present invention.

Claims

1. A method for recycling and reusing the copper core of the pole of a power battery, characterized in that: It includes the following steps: a. Immerse the pole columns of waste power batteries into an alkaline solution for ultrasonic degreasing, then take out the pole columns and immerse them in hot water for ultrasonic cleaning, take out the pole columns, wash them with running water, and then blow-dry the pole columns; b. Immerse the dried pole columns into molten liquid lead-antimony alloy, heat and melt them, and then put the pole columns into a turnover box and let them cool to room temperature; c. Immerse the melted pole columns into an electrochemically stripping solution to electrolyze out the copper cores of the pole columns, and then first wash the copper cores of the pole columns with running water and then wash them with battery water; The formula of the electrochemically stripping solution is: malic acid 70g / L - 90g / L, acetic acid 50g / L - 80g / L, lead acetate 60g / L - 120g / L, antimony acetate 5g / L - 15g / L, stannous chloride 20g / L - 40g / L, β-naphthol 0.5g / L - 3.0g / L, HJX-2 stabilizer 20mL / L - 30mL / L; The HJX-2 stabilizer is compounded by two or more of methanesulfonic acid, sulfamic acid, fatty acid salts and polyether polyols; d. Immerse the copper cores of the pole columns into a chemically stripping solution for soaking, then first wash the copper cores of the pole columns with running water and then wash them with battery water, and finally blow-dry the copper cores of the pole columns; The formula of the chemically stripping solution is: hydrochloric acid 100mL / L - 200mL / L, hydrogen peroxide 30mL / L - 50mL / L, sodium tartrate 20g / L - 40g / L, sodium dodecyl sulfate 40mg / L - 80mg / L, alanine 15mg / L - 40mg / L.

2. The method for recycling the pole copper core of the power battery according to claim 1, characterized in that: The alkaline solution in step a is a mixed solution of Na2CO3 and Na3PO4·12H2O, with a temperature of 75°C to 85°C and a density of 1.015 g / cm 3 ~1.020 g / cm 3 .

3. The method for recycling the pole copper core of the power battery according to claim 2, characterized in that: In step b, the heating and melting temperature of the lead-antimony alloy pot is 350°C - 400°C, and the heating and melting time is 30min - 45min.

4. The method for recycling and reusing the pole copper core of the power battery according to claim 3, characterized in that: The electrolysis time in step c is 60min - 75min.

5. The method for recycling the pole copper core of the power battery according to claim 4, characterized in that: The soaking time in step d is 10min - 20min.

6. The method for recycling and reusing the pole copper core of a power battery according to claim 1 is characterized in that: The process conditions for electrochemically stripping the plating in step c are as follows: anodic current density is 1.5 A / dm 2 ~3.0 A / dm 2 , temperature is 15°C~35°C, and the frequency of cathode movement is 20 times / min~40 times / min.

7. The method for recycling the pole copper core of the power battery according to claim 1 is characterized in that: The process conditions for chemical stripping in step d are: temperature 15°C - 35°C, solution stirring speed 200r / min - 500r / min.

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