A method for preparing a rechargeable battery for recycling waste zinc-manganese dry batteries

Abstract

The present invention relates to a method for preparing a rechargeable battery from recycled zinc-manganese dry cells, comprising: 1) preparing electrode powder, 2) preparing electrode materials, and 3) preparing a secondary battery. The waste positive electrode is chemically converted to restore the activity of the positive electrode material, and the waste negative electrode, after simple treatment, can be used as the negative electrode of the secondary battery. The technical solution provided by the present invention achieves a positive and negative electrode utilization rate exceeding 95%, enabling effective resource recycling and addressing the current environmental pollution and recycling difficulties of dry cell batteries, thus meeting current environmental protection requirements.

Description

Technical Field

[0001] The present invention relates to the field of electrochemical energy storage, and in particular to a method for preparing a resource-regenerated rechargeable battery of waste zinc-manganese dry batteries. Background Art

[0002] According to statistics, my country produces 15 billion dry-cell batteries annually, 70% of which are zinc-manganese batteries. Used dry-cell batteries contain large amounts of non-ferrous metals and alkali. If not recycled and disposed of, they can cause significant environmental pollution. Currently, environmental management of discarded dry-cell batteries in my country is largely nonexistent. The tens of billions of batteries scrapped annually are mostly discarded without recycling, posing a potential threat to the ecological environment and public health.

[0003] Currently, the primary methods for recycling and reusing zinc-manganese dry-cell batteries rely on hydrometallurgical or pyrometallurgical processing techniques. Hydrometallurgical recycling involves immersing the batteries in sulfuric acid to generate soluble salts, followed by electrolysis to extract the heavy metals. However, the hydrometallurgical process is lengthy and can cause secondary pollution in wastewater treatment, making it uneconomical and environmentally unsuitable. Pyrometallurgy exploits the differences in melting and boiling points of different metal oxides, allowing them to evaporate and split at different temperatures. This method is extremely difficult to implement in batches and has very high economic requirements. Furthermore, metallurgical processing is energy-intensive, lengthy, and labor-intensive. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a method for preparing a resource-based regeneration rechargeable battery from waste zinc-manganese dry batteries. The method has low cost and good repair effect, and can effectively reuse the positive electrode materials of the waste dry batteries to solve the problems of discarding waste dry batteries, serious environmental pollution, immature recycling technology and high cost in the existing technology.

[0005] The purpose of the present invention is achieved by adopting the following technical solutions:

[0006] The present invention provides a method for preparing a rechargeable battery by recycling waste zinc-manganese dry batteries. The improvement of the method is that the method comprises the following steps:

[0007] Step 1: Cut the used zinc-manganese dry batteries after they are fully discharged;

[0008] Step 2: Separate the stainless steel casing, diaphragm, positive electrode and negative electrode of the disassembled battery;

[0009] Step 3: crushing the separated crushed electrode material and screening it;

[0010] Step 4: The negative electrode powder obtained by screening is washed with water, filtered and centrifuged, and then placed in an oven for constant temperature drying to obtain a mixture of Zn and ZnO; the positive electrode powder obtained by screening is washed with water, filtered and dried, and then placed in a muffle furnace for calcination and decarbonization to obtain a mixture of MnO2 and Mn2O3;

[0011] Step 5: adding sodium source powder to the mixture of MnO2 and Mn2O3 according to the Mn / O ratio in the mixture of MnO2 and Mn2O3 in step 4;

[0012] Step 6: Add ball milling beads and dispersant to the mixture in step 5 and ball mill to obtain a precursor;

[0013] Step 7: After drying the obtained precursor, place it in a muffle furnace and calcine it in an air atmosphere to obtain the positive electrode repair product Na 0.44 MnO2;

[0014] Step 8: Repair the positive electrode product Na 0.44 MnO2 is mixed with activated carbon, PTFE adhesive is added, rolled into a film, and pressed on a stainless steel mesh to make the positive electrode; a mixture of Zn and ZnO is mixed with activated carbon, PTFE adhesive is added, rolled into a film, and pressed on a stainless steel mesh to make the negative electrode;

[0015] Step 9: Match the positive electrode and negative electrode in step 8, add sodium salt solution to make Zn / Na 0.44 MnO2 aqueous solution secondary battery.

[0016] Preferably, in step 3, the electrode powder is screened by sieving through a 60-300 mesh sieve.

[0017] Preferably, the drying temperature in steps 4 and 7 is 60-110° C., and the drying time is 0.5-6 h.

[0018] Preferably, in step 4, the calcination temperature in the muffle furnace is 500-800° C., and the calcination time is 5-15 h.

[0019] Preferably, in step 5, the sodium source is one or more of sodium acetate, sodium carbonate, sodium nitrate, sodium citrate, sodium oxalate, and sodium hydroxide.

[0020] Preferably, in step 6, the dispersant is one or more of methanol, ethanol, isopropanol, acetone, and butanone.

[0021] Preferably, in step 6, the ball milling time is 2 to 6 hours.

[0022] Preferably, in step 7, the calcination temperature in the muffle furnace is 750-950° C., and the calcination time is 5-20 h.

[0023] Preferably, in step 8, Na 0.44 The mass ratio of MnO2, activated carbon and polytetrafluoroethylene is 5:4:1 to 8:1:1.

[0024] Preferably, in step 8, the mass ratio of the mixture of Zn and ZnO, activated carbon and polytetrafluoroethylene is 5:4:1 to 8:1:1.

[0025] Preferably, in step 9, the sodium salt in the sodium salt aqueous solution is one or more of sodium acetate, sodium nitrate, sodium sulfate, and sodium hydroxide, and the concentration of the sodium salt is 1 to 10 mol / L.

[0026] Preferably, in step 9, the aqueous solution secondary battery is one or a combination of square aluminum shell battery, soft pack battery or button battery.

[0027] Compared with the closest prior art, the present invention has the following beneficial effects:

[0028] 1. The present invention provides a technical solution to restore the activity of the positive electrode material by in-situ conversion to Na0.44MnO2. The regeneration effect is good, the activity recovery rate is high, and the cost is low compared to other methods in the prior art.

[0029] 2. The present invention provides a technical solution, in which waste positive electrodes are converted into new positive electrodes through a chemical conversion method, and waste negative electrodes can be used as negative electrodes for secondary batteries after simple treatment. The utilization rate of positive and negative electrodes reaches more than 95%, which can effectively reuse resources and solve the current problems of dry batteries polluting the environment and being difficult to recycle. The cost is controllable, it has actual economic benefits, and is suitable for large-scale promotion to meet the current requirements for environmental protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a process flow chart for recycling waste zinc-manganese dry batteries into rechargeable batteries according to the present invention;

[0031] Figure 2 This is the XRD pattern of the disassembled battery negative electrode after treatment;

[0032] Figure 3 This is the XRD pattern of the disassembled battery cathode after treatment;

[0033] Figure 4 This is the XRD pattern of the positive electrode after repair and regeneration in Example 1 of the present invention;

[0034] Figure 5 This is a SEM image of the positive electrode after repair and regeneration in Example 2 of the present invention;

[0035] Figure 6 3 is a cycle curve diagram of the regenerated secondary battery in Example 3 of the present invention. DETAILED DESCRIPTION

[0036] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0038] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in this field can be used. If the manufacturer of the reagents or instruments is not specified, they are all commercially available conventional reagents.

[0039] Example 1

[0040] The present invention provides a method for preparing a rechargeable battery by recycling waste zinc-manganese dry batteries. Figure 1 As shown, the method includes the following steps:

[0041] Step 1: Cut the used zinc-manganese dry batteries after they are fully discharged;

[0042] Step 2: Separate the stainless steel casing, diaphragm, positive electrode and negative electrode of the disassembled battery;

[0043] Step 3: crushing the separated crushed electrode material and screening it;

[0044] Step 4: If Figure 2 As shown, the negative electrode powder obtained by screening is washed with water, filtered and centrifuged, and then placed in an oven for constant temperature drying to obtain a mixture of Zn and ZnO; Figure 3 As shown, the positive electrode powder obtained by screening is washed, filtered and dried, and then placed in a muffle furnace for calcination to remove carbon to obtain a mixture of MnO2 and Mn2O3;

[0045] Step 5: adding sodium source powder to the mixture of MnO2 and Mn2O3 according to the Mn / O ratio in the mixture of MnO2 and Mn2O3 in step 4;

[0046] Step 6: Add ball milling beads and dispersant to the mixture in step 5 and ball mill to obtain a precursor;

[0047] Step 7: After drying the obtained precursor, place it in a muffle furnace and calcine it in an air atmosphere to obtain the positive electrode repair product Na 0.44 MnO2;

[0048] Step 8: Repair the positive electrode product Na 0.44 MnO2 is mixed with activated carbon, PTFE adhesive is added, rolled into a film, and pressed on a stainless steel mesh to make the positive electrode; a mixture of Zn and ZnO is mixed with activated carbon, PTFE adhesive is added, rolled into a film, and pressed on a stainless steel mesh to make the negative electrode;

[0049] Step 9: Match the positive electrode and negative electrode in step 8, add sodium salt solution to make Zn / Na 0.44 MnO2 aqueous solution secondary battery.

[0050] Specifically, in step 3, the electrode powder is screened by sieving through a 60-mesh sieve.

[0051] Specifically, the drying temperature in steps 4 and 7 is both 60° C., and the drying time is both 0.5 h.

[0052] Specifically, in step 4, the calcination temperature in the muffle furnace is 500° C., and the calcination time is 5 hours.

[0053] Specifically, in step 5, the sodium source is one or more of sodium acetate, sodium carbonate, sodium nitrate, sodium citrate, sodium oxalate, and sodium hydroxide.

[0054] Specifically, in step 6, the dispersant is one or more of methanol, ethanol, isopropanol, acetone, and butanone.

[0055] Specifically, in step 6, the ball milling time is 2 hours.

[0056] Specifically, in step 7, the calcination temperature in the muffle furnace is 750° C., and the calcination time is 5 hours.

[0057] Specifically, in step 8, Na 0.44 The mass ratio of MnO2, activated carbon and polytetrafluoroethylene is 5:4:1.

[0058] Specifically, in step 8, the mass ratio of the mixture of Zn and ZnO, activated carbon and polytetrafluoroethylene is 5:4:1.

[0059] Specifically, in step 9, the sodium salt in the sodium salt aqueous solution is one or more of sodium acetate, sodium nitrate, sodium sulfate, and sodium hydroxide, and the concentration of the sodium salt is 1 mol / L.

[0060] Specifically: in step 9, the aqueous solution secondary battery is one or a combination of square aluminum shell battery, soft pack battery or button battery.

[0061] Example 2

[0062] The present invention provides a method for preparing a rechargeable battery by recycling waste zinc-manganese dry batteries. Figure 1 As shown, the method includes the following steps:

[0063] Step 1: Cut the used zinc-manganese dry batteries after they are fully discharged;

[0064] Step 2: Separate the stainless steel casing, diaphragm, positive electrode and negative electrode of the disassembled battery;

[0065] Step 3: crushing the separated crushed electrode material and screening it;

[0066] Step 4: If Figure 2 As shown, the negative electrode powder obtained by screening is washed with water, filtered and centrifuged, and then placed in an oven for constant temperature drying to obtain a mixture of Zn and ZnO; Figure 3 As shown, the positive electrode powder obtained by screening is washed, filtered and dried, and then placed in a muffle furnace for calcination to remove carbon to obtain a mixture of MnO2 and Mn2O3;

[0067] Step 5: adding sodium source powder to the mixture of MnO2 and Mn2O3 according to the Mn / O ratio in the mixture of MnO2 and Mn2O3 in step 4;

[0068] Step 6: Add ball milling beads and dispersant to the mixture in step 5 and ball mill to obtain a precursor;

[0069] Step 7: After drying the obtained precursor, place it in a muffle furnace and calcine it in an air atmosphere to obtain the positive electrode repair product Na 0.44 MnO2;

[0070] Step 8: Repair the positive electrode product Na 0.44 MnO2 is mixed with activated carbon, PTFE adhesive is added, rolled into a film, and pressed on a stainless steel mesh to make the positive electrode; a mixture of Zn and ZnO is mixed with activated carbon, PTFE adhesive is added, rolled into a film, and pressed on a stainless steel mesh to make the negative electrode;

[0071] Step 9: Match the positive electrode and negative electrode in step 8, add sodium salt solution to make Zn / Na 0.44 MnO2 aqueous solution secondary battery.

[0072] Specifically, in step 3, the electrode powder is screened by sieving through a 200-mesh sieve.

[0073] Specifically, the drying temperature in steps 4 and 7 is both 80° C., and the drying time is both 3 h.

[0074] Specifically, in step 4, the calcination temperature in the muffle furnace is 700° C., and the calcination time is 10 h.

[0075] Specifically, in step 5, the sodium source is one or more of sodium acetate, sodium carbonate, sodium nitrate, sodium citrate, sodium oxalate, and sodium hydroxide.

[0076] Specifically, in step 6, the dispersant is one or more of methanol, ethanol, isopropanol, acetone, and butanone.

[0077] Specifically, in step 6, the ball milling time is 3 hours.

[0078] Specifically, in step 7, the calcination temperature in the muffle furnace is 800° C., and the calcination time is 12 h.

[0079] Specifically, in step 8, Na 0.44 The mass ratio of MnO2, activated carbon and polytetrafluoroethylene is 7:2:1.

[0080] Specifically, in step 8, the mass ratio of the mixture of Zn and ZnO, activated carbon and polytetrafluoroethylene is 7:2:1.

[0081] Specifically, in step 9, the sodium salt in the sodium salt aqueous solution is one or more of sodium acetate, sodium nitrate, sodium sulfate, and sodium hydroxide, and the concentration of the sodium salt is 5 mol / L.

[0082] Specifically: in step 9, the aqueous solution secondary battery is one or a combination of square aluminum shell battery, soft pack battery or button battery.

[0083] Example 3

[0084] The present invention provides a method for preparing a rechargeable battery by recycling waste zinc-manganese dry batteries. Figure 1 As shown, the method includes the following steps:

[0085] Step 1: Cut the used zinc-manganese dry batteries after they are fully discharged;

[0086] Step 2: Separate the stainless steel casing, diaphragm, positive electrode and negative electrode of the disassembled battery;

[0087] Step 3: crushing the separated crushed electrode material and screening it;

[0088] Step 4: If Figure 2 As shown, the negative electrode powder obtained by screening is washed with water, filtered and centrifuged, and then placed in an oven for constant temperature drying to obtain a mixture of Zn and ZnO; Figure 3 As shown, the positive electrode powder obtained by screening is washed, filtered and dried, and then placed in a muffle furnace for calcination to remove carbon to obtain a mixture of MnO2 and Mn2O3;

[0089] Step 5: adding sodium source powder to the mixture of MnO2 and Mn2O3 according to the Mn / O ratio in the mixture of MnO2 and Mn2O3 in step 4;

[0090] Step 6: Add ball milling beads and dispersant to the mixture in step 5 and ball mill to obtain a precursor;

[0091] Step 7: After drying the obtained precursor, place it in a muffle furnace and calcine it in an air atmosphere to obtain the positive electrode repair product Na 0.44 MnO2;

[0092] 3) Preparation of secondary batteries:

[0093] Step 8: Repair the positive electrode product Na 0.44 MnO2 is mixed with activated carbon, PTFE adhesive is added, rolled into a film, and pressed on a stainless steel mesh to make the positive electrode; a mixture of Zn and ZnO is mixed with activated carbon, PTFE adhesive is added, rolled into a film, and pressed on a stainless steel mesh to make the negative electrode;

[0094] Step 9: Match the positive electrode and negative electrode in step 8, add sodium salt solution to make Zn / Na 0.44 MnO2 aqueous solution secondary battery.

[0095] Specifically, in step 3, the electrode powder is screened by sieving through a 300-mesh sieve.

[0096] Specifically, the drying temperature in steps 4 and 7 is both 110° C., and the drying time is both 6 h.

[0097] Specifically, in step 4, the calcination temperature in the muffle furnace is 800° C., and the calcination time is 15 h.

[0098] Specifically, in step 5, the sodium source is one or more of sodium acetate, sodium carbonate, sodium nitrate, sodium citrate, sodium oxalate, and sodium hydroxide.

[0099] Specifically, in step 6, the dispersant is one or more of methanol, ethanol, isopropanol, acetone, and butanone.

[0100] Specifically, in step 6, the ball milling time is 6 hours.

[0101] Specifically, in step 7, the calcination temperature in the muffle furnace is 950° C., and the calcination time is 20 h.

[0102] Specifically, in step 8, Na 0.44 The mass ratio of MnO2, activated carbon and polytetrafluoroethylene is 8:1:1.

[0103] Specifically, in step 8, the mass ratio of the mixture of Zn and ZnO, activated carbon and polytetrafluoroethylene is 8:1:1.

[0104] Specifically, in step 9, the sodium salt in the sodium salt aqueous solution is one or more of sodium acetate, sodium nitrate, sodium sulfate, and sodium hydroxide, and the concentration of the sodium salt is 10 mol / L.

[0105] Specifically: in step 9, the aqueous solution secondary battery is one or a combination of square aluminum shell battery, soft pack battery or button battery.

[0106] Test Example 1

[0107] The sample of the regenerated positive electrode repair product of the waste dry battery provided in Example 1 was tested to obtain its crystal structure information, such as Figure 4 As shown in the XRD, it can be seen that the prepared sample is 0.44 The peaks of the MnO2 standard spectrum are basically consistent, and there are fewer impurity peaks, which can prove that the material prepared by this method is of high purity.

[0108] The sample of the regenerated positive electrode repair product of the waste dry battery provided in Example 2 was tested to obtain its surface morphology information, such as Figure 5 As shown in the SEM, the material has a nanorod-like structure with uniform size, about 2 μm in length and 300 nm in diameter.

[0109] The Zn / Na 0.44 The MnO2 aqueous solution secondary battery was tested and its cycle curve at a current density of 20 mA / g was obtained, as shown in Figure 6 As shown in the figure, it can be seen that the reversible capacity of the battery in the first week is 43 mAh / g. After 100 cycles, the capacity retention rate is 90%, and the cycle performance is excellent.

[0110] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A method for preparing a rechargeable battery by recycling waste zinc-manganese dry batteries, characterized in that: The method comprises the following steps: Step 1: Cut the used zinc-manganese dry batteries after they are fully discharged; Step 2: Separate the stainless steel casing, diaphragm, positive electrode and negative electrode of the disassembled battery; Step 3: crushing the separated crushed electrode material and screening it; Step 4: The negative electrode powder obtained by screening is washed with water, filtered and centrifuged, and then placed in an oven for constant temperature drying to obtain a mixture of Zn and ZnO; the positive electrode powder obtained by screening is washed with water, filtered and dried, and then placed in a muffle furnace for calcination and decarbonization to obtain a mixture of MnO2 and Mn2O3; Step 5: adding sodium source powder to the mixture of MnO2 and Mn2O3 according to the Mn / O ratio in the mixture of MnO2 and Mn2O3 in step 4; Step 6: Add ball milling beads and dispersant to the mixture in step 5 and ball mill to obtain a precursor; Step 7: After drying the obtained precursor, place it in a muffle furnace and calcine it in an air atmosphere to obtain the positive electrode repair product Na 0.44 MnO2; Step 8: Repair the positive electrode product Na 0.44 MnO2 is mixed with activated carbon, PTFE adhesive is added, rolled into a film, and pressed on a stainless steel mesh to make the positive electrode; a mixture of Zn and ZnO is mixed with activated carbon, PTFE adhesive is added, rolled into a film, and pressed on a stainless steel mesh to make the negative electrode; Step 9: Match the positive electrode and negative electrode in step 8, add sodium salt solution to make Zn / Na 0.44 MnO2 aqueous solution secondary battery.

2. The method according to claim 1, wherein: In the step 3, the electrode powder is screened by sieving through a 60-300 mesh sieve.

3. The method according to claim 1, wherein The drying temperature in steps 4 and 7 is both 60-110° C., and the drying time is both 0.5-6 h.

4. The method according to claim 1, wherein In the step 4, the calcination temperature in the muffle furnace is 500-800° C., and the calcination time is 5-15 h.

5. The method according to claim 1, wherein In step 5, the sodium source is one or more of sodium acetate, sodium carbonate, sodium nitrate, sodium citrate, sodium oxalate, and sodium hydroxide.

6. The method according to claim 1, wherein In step 6, the dispersant is one or more of methanol, ethanol, isopropanol, acetone, and butanone.

7. The method according to claim 1, wherein In step 6, the ball milling time is 2 to 6 hours.

8. The method according to claim 1, wherein In the step 7, the calcination temperature in the muffle furnace is 750-950° C., and the calcination time is 5-20 h.

9. The method according to claim 1, wherein In step 8, Na 0.44 The mass ratio of MnO2, activated carbon and polytetrafluoroethylene is 5:4:1 to 8:1:

1.

10. The method according to claim 1, wherein In step 8, the mass ratio of the mixture of Zn and ZnO, activated carbon and polytetrafluoroethylene is 5:4:1 to 8:1:

1.

11. The method according to claim 1, wherein In step 9, the sodium salt in the sodium salt aqueous solution is one or more of sodium acetate, sodium nitrate, sodium sulfate, and sodium hydroxide, and the concentration of the sodium salt is 1 to 10 mol / L.

12. The method according to claim 1, wherein: In step 9, the aqueous solution secondary battery is one or a combination of square aluminum shell battery, soft pack battery or button battery.

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