Miniature battery and preparation and packaging method thereof

Abstract

The invention provides a micro battery. The micro battery comprises a capillary tube, an active material arranged in the capillary tube and used as a positive electrode, a copper wire with one end arranged in the capillary tube, electrolyte injected into the capillary tube, and a zinc wire with one end arranged in the other end of the capillary tube and used as a negative electrode. The invention also provides a preparation and packaging method of the micro battery. According to the minicell and the preparation and packaging method thereof, the minicell is simple in structure, the preparation and sealing method of the minicell is simple, and the preparation and packaging cost is relatively low.

Description

Technical Field

[0001] The present invention relates to the technical field of micro energy storage devices, and in particular to a micro battery and a preparation and packaging method thereof. Background Art

[0002] Micro batteries have broad application prospects in the fields of medical treatment, aerospace, Internet of Things, etc. Although the improvement of active materials involved in batteries has been rapidly developed, the preparation and sealing of small-sized micro batteries are relatively difficult.

[0003] At present, in order to solve the problem of difficulty in preparing and sealing micro energy storage devices, physical vapor deposition and electrochemical deposition methods are usually used to prepare active materials, and then ultrasonic welding, inert coating and glue coating are combined to seal the micro battery. However, these micro battery preparation and sealing methods have the problems of high cost, difficult operation, poor sealing, etc. Moreover, for micro batteries with a size of no more than 1mm, it is more difficult to achieve the above preparation and sealing methods.

[0004] Therefore, there is an urgent need for a micro battery with a simple structure, simple preparation and sealing, and low cost, and a preparation and packaging method thereof. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a micro battery with simple structure, simple preparation and sealing and low cost, and a preparation and packaging method thereof.

[0006] To solve the above technical problems, the present invention provides a micro battery, comprising a capillary, an active material arranged in the capillary as a positive electrode, a copper wire arranged at one end in the capillary, an electrolyte injected into the capillary, and a zinc wire arranged at one end in the other end of the capillary as a negative electrode;

[0007] The active substance in the active material is MnO2, V2O5, Mn3O4, Co3O4 or LiFePO4;

[0008] The surface of the copper wire portion disposed in the capillary is coated with silver glue, and the copper wire and the capillary are fixed and sealed by the silver glue;

[0009] The surface of the zinc wire portion arranged in the capillary is coated with polyimide, and the zinc wire and the capillary are fixed and sealed by ultraviolet light curing glue.

[0010] Furthermore, the active material includes the active substance, a binder and a conductive agent.

[0011] Furthermore, the mass ratio of the active material, the binder and the conductive agent is (5-10):1:1.

[0012] Furthermore, the binder is polyvinylidene fluoride, polytetrafluoroethylene, polyimide or acrylic acid; the conductive agent is carbon nanotubes, granular Super-P, Ketjen black, fibrous vapor-grown carbon fiber, flaky KS-6, SFG-6, graphene or graphite.

[0013] Furthermore, the binder in the active material film layer is dissolved in N-methylpyrrolidone, acetone or dimethylacetamide to form a binder glue solution, and the mass percentage of the binder in the binder glue solution is 5%-15%.

[0014] Furthermore, the electrolyte is a ZnSO4 electrolyte, and the concentration of the ZnSO4 electrolyte is 0.5M-1.5M.

[0015] Furthermore, the capillary is a glass capillary, a plastic capillary or a metal capillary.

[0016] Furthermore, the inner diameter of the capillary is 0.8-1.5 mm and the length is 1-2 mm.

[0017] The present invention also provides a method for preparing and packaging a micro battery, comprising the following steps:

[0018] Dissolving the adhesive in N-methylpyrrolidone, acetone or dimethylacetamide to form an adhesive glue;

[0019] The active material, the binder glue and the conductive agent are mixed to obtain the active material slurry;

[0020] The active material slurry is injected into the capillary tube, and after drying, an active material for the positive electrode is formed in the capillary tube;

[0021] Insert a copper wire coated with silver glue into one end of the capillary tube so that the copper wire contacts the active material, and fix and seal the copper wire and the capillary tube with silver glue;

[0022] Inject electrolyte into the capillary from the other end of the capillary;

[0023] Insert a polyimide-coated zinc wire into the active material from the end of the capillary tube injected with electrolyte, and fix and seal the zinc wire and the capillary tube with ultraviolet light curing adhesive.

[0024] Furthermore, the drying is to place the capillary in an oven and dry it at 50°C-100°C for 1-4 hours until the solvent in the active material slurry is completely volatilized to form active material in the capillary. The present invention provides a micro-battery and a preparation and packaging method thereof, which completely volatilizes the solvent in the active material slurry injected into the capillary by a drying method, forms an active material in the capillary as the positive electrode of the micro-battery, and then injects an electrolyte into the capillary, and inserts a copper wire and a zinc wire at both ends of the capillary, respectively, and cures and seals the capillary with silver glue and ultraviolet light curing glue, respectively, and leads out wires at both ends of the capillary to obtain a micro-battery. The obtained micro-battery has a simple structure, and the preparation and packaging method of the micro-battery has a simple operation process, low cost, high economic benefits, and is worthy of promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic diagram of the structure of a micro battery provided by an embodiment of the present invention;

[0026] Figure 2 Schematic diagram of the charge and discharge specific capacity of the micro battery prepared in an embodiment of the present invention. DETAILED DESCRIPTION

[0027] See also Figure 1 A micro battery provided by an embodiment of the present invention includes a capillary 1, an active material 2 distributed in the capillary 1 as a positive electrode, a copper wire 3 with one end arranged in the capillary 1, an electrolyte 4 injected into the capillary, and a zinc wire 5 with one end arranged in the other end of the capillary 1 as a negative electrode.

[0028] Among them, the active material in the active material 2 is MnO2, V2O5, Mn3O4, Co3O4 or LiFePO4.

[0029] As a best specific embodiment of the present invention, the active substance in the active material 2 is MnO2.

[0030] The surface of the copper wire 3 disposed in the capillary 1 is coated with silver glue, which can adhere the copper wire 3 and the active material 2 together, and the copper wire 3 and the capillary 1 are fixedly sealed by the silver glue 6. The surface of the zinc wire 5 disposed in the active material 2 in the capillary 1 is coated with polyimide 7, which acts as a diaphragm to prevent the zinc wire 5 as the negative electrode from directly contacting the active material 2 as the positive electrode and causing a short circuit. The zinc wire 5 and the capillary 1 are fixedly sealed by ultraviolet light curing glue 8.

[0031] The active material 2 includes an active substance, a binder and a conductive agent.

[0032] Among them, the mass ratio of active material, binder and conductive agent is (5-10):1:1.

[0033] As a best specific implementation manner of the present invention, the mass ratio of the active material, the binder and the conductive agent is 8:1:1.

[0034] The binder is polyvinylidene fluoride (PVDF), polytetrafluoroethylene, polyimide or acrylic acid. The conductive agent is carbon nanotube, granular Super-P, Ketjen black, fibrous vapor-grown carbon fiber, sheet KS-6, SFG-6, graphene or graphite.

[0035] As a best embodiment of the present invention, the binder is polyvinylidene fluoride (PVDF) and the conductive agent is carbon nanotube.

[0036] The binder in the active material 2 is first dissolved in N-methylpyrrolidone, acetone or dimethylacetamide to form a binder glue before being mixed with the active material and the conductive agent, and the mass percentage of the binder in the binder glue is 5%-15%.

[0037] As a best specific implementation of the present invention, polyvinylidene fluoride (PVDF) is first dissolved in N-methylpyrrolidone (NMP) to form a PVDF glue solution, and the mass percentage of PVDF in the PVDF glue solution is 10%.

[0038] Among them, the electrolyte 4 is a ZnSO4 electrolyte, and the concentration of the ZnSO4 electrolyte is 0.5M-1.5M.

[0039] As a specific implementation of the present invention, the electrolyte 4 is a ZnSO4 electrolyte, and the concentration of the ZnSO4 electrolyte is 1M.

[0040] The capillary 1 is a glass capillary, a plastic capillary or a metal capillary.

[0041] As a best specific implementation of the present invention, the capillary 1 is a glass capillary.

[0042] The inner diameter of the capillary 1 is 0.8-1.5 mm and the length is 1-2 mm.

[0043] As a best embodiment of the present invention, the inner diameter of the capillary 1 is 1 mm and the length is 1.5 mm.

[0044] The present invention provides a method for preparing and packaging a micro battery, comprising the following steps:

[0045] Step 1) dissolving an adhesive in N-methylpyrrolidone, acetone or dimethylacetamide to form an adhesive glue solution;

[0046] Step 2) mixing the active material, the binder glue and the conductive agent to obtain an active material slurry;

[0047] Step 3) The active material slurry is injected into the capillary 1 from one end of the capillary (i.e., the right end of the capillary), and a certain space is reserved at the other end of the capillary (i.e., the left end of the capillary), and after drying, the active material 2 is formed in the capillary 1. For the sake of convenience, the end of the capillary inserted with the copper wire 3 is regarded as the right end, and the end of the capillary inserted with the zinc wire 5 is regarded as the left end.

[0048] Step 4) inserting a silver-coated copper wire 3 into the right end of the capillary 1 so that the copper wire 3 is in contact with the active material 2, and fixing and sealing the copper wire 3 and the capillary 1 with silver glue 6;

[0049] Step 5) injecting ZnSO4 electrolyte 4 from the left end of the capillary 1 into the remaining space in the capillary 1 that is not filled with the active material 2;

[0050] Step 6) Insert the zinc wire 5 coated with polyimide 7 from the left end of the capillary 1, so that the zinc wire is inserted into the active material 2. The polyimide 7 coated on the surface of the zinc wire 5 can separate the zinc wire 5 as the negative electrode from the active material 2 as the positive electrode to avoid short circuit problems. Then use ultraviolet light curing glue 8 to fix and seal the zinc wire 5 and the capillary 1.

[0051] The drying step is to place the capillary 1 in an oven at 50° C.-100° C. for 1-4 hours, until the solvent in the active material slurry is completely volatilized to form the active material 2 in the capillary 1 .

[0052] As a best specific embodiment of the present invention, drying is to place the capillary 1 in an oven and dry it at 80° C. for 2 hours until the solvent in the active material slurry is completely volatilized to form the active material 2 in the capillary 1 .

[0053] Among them, the active material in the active material 2 is MnO2, V2O5, Mn3O4, Co3O4 or LiFePO4.

[0054] As a best specific embodiment of the present invention, the active substance in the active material 2 is MnO2.

[0055] Among them, the mass ratio of active material, binder and conductive agent is (5-10):1:1.

[0056] As a best specific embodiment of the present invention, the mass ratio of the active material, the binder and the conductive agent is 8:1:1.

[0057] The binder is polyvinylidene fluoride (PVDF), polytetrafluoroethylene, polyimide or acrylic acid. The conductive agent is carbon nanotube, granular Super-P, Ketjen black, fibrous vapor-grown carbon fiber, sheet KS-6, SFG-6, graphene or graphite.

[0058] As a best specific implementation of the present invention, the binder is polyvinylidene fluoride (PVDF) and the conductive agent is carbon nanotube.

[0059] The binder in the active material 2 is first dissolved in N-methylpyrrolidone, acetone or dimethylacetamide to form a binder glue before being mixed with the active material and the conductive agent, and the mass percentage of the binder in the binder glue is 5%-15%.

[0060] As a best specific implementation of the present invention, polyvinylidene fluoride (PVDF) is first dissolved in N-methylpyrrolidone (NMP) to form a PVDF glue solution, and the mass percentage of PVDF in the PVDF glue solution is 10%.

[0061] Among them, the electrolyte 4 is a ZnSO4 electrolyte, and the concentration of the ZnSO4 electrolyte is 0.5M-1.5M.

[0062] As a specific implementation of the present invention, the concentration of the ZnSO4 electrolyte is 1M.

[0063] The capillary 1 is a glass capillary, a plastic capillary or a metal capillary.

[0064] As a best specific implementation of the present invention, the capillary 1 is a glass capillary.

[0065] The inner diameter of the capillary 1 is 0.8-1.5 mm and the length is 1-2 mm.

[0066] As a best embodiment of the present invention, the inner diameter of the capillary 1 is 1 mm and the length is 1.5 mm.

[0067] The preparation and packaging of a micro battery provided by the present invention will be specifically described below through a preferred embodiment.

[0068] MnO2 nanowires are selected as the active material of the seed positive electrode. Of course, as other embodiments, V2O5, Co2O3, Fe3O4, etc. can also be used.

[0069] Using polyvinylidene fluoride (PVDF) as a binder, polyvinylidene fluoride (PVDF) is first dissolved in N-methylpyrrolidone (NMP) to form a PVDF glue with a mass percentage of 10%. Using carbon nanotubes as a conductive agent, carbon nanotubes, PVDF glue and MnO2 nanowires are mixed and stirred for 24 hours to form a uniform suspension, that is, to obtain an active material slurry. Among them, the mass ratio of active material, binder and conductive agent is 8:1:1.

[0070] The active material slurry is injected into the glass capillary 1 from the right end thereof by a syringe, and a certain space is reserved at the left end thereof. The glass capillary 1 has an outer diameter of 1 mm, an inner diameter of 0.8 mm, and a length of 1.5 mm.

[0071] Then, the glass capillary 1 is placed in an oven and dried at 80° C. for 2 hours. This process is repeated 10 times until the solvent in the active material slurry is completely volatilized to form the active material 2 as the positive electrode in the glass capillary 1 .

[0072] A copper wire 3 is inserted into the right end of the glass capillary 1, and silver glue is coated on the end of the copper wire 3 to bond the copper wire 3 to the active material. The connection between the right end of the glass capillary 1 and the copper wire 3 is fixed and sealed with silver glue 6.

[0073] A 1 M ZnSO 4 aqueous solution is injected as the electrolyte 4 into the glass capillary 1 from the other end of the glass capillary 1 .

[0074] Then, a zinc wire 5 is inserted from the left end of the glass capillary 1 into the interior of the glass capillary 1 and extends into the interior of the active material 2, with the zinc wire 5 serving as the negative electrode. In addition, in order to prevent the zinc wire 5 as the negative electrode from directly contacting the active material 2 as the positive electrode in the glass capillary 1 and causing a short circuit, the surface of the zinc wire 5 inserted into the interior of the active material 2 in the glass capillary 1 is coated with polyimide 7, which has the function of a diaphragm to insulate and isolate the positive and negative electrodes from direct contact.

[0075] Finally, the zinc wire 5 and the capillary 1 are quickly fixed and sealed with ultraviolet light curing glue 8 at the connection between the left part of the glass capillary 1 and the zinc wire 5. In this way, a micro battery can be obtained.

[0076] The charge-discharge specific capacity of the micro-battery prepared by the micro-battery preparation and packaging method provided in the embodiment of the present invention is as follows: Figure 2 As shown. Figure 2 It can be seen that the charging and discharging performance of the microbattery prepared in the embodiment of the present invention can fully meet the use requirements of energy devices including lithium-ion batteries, sodium-ion batteries, lithium-sulfur batteries, lithium-air batteries, supercapacitors, etc.

[0077] The micro-battery preparation and packaging method provided in the embodiment of the present invention has a small volume, a diameter of only 1 mm, and a length of only 1.5 mm, and the preparation and packaging method is simple to operate, has a low preparation cost, and has a high economic benefit, and is worthy of promotion and application. At the same time, the micro-battery prepared in the embodiment of the present invention has good charging and discharging performance, which can fully meet the needs of use.

[0078] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A micro battery, characterized in that: It includes a capillary, an active material arranged in the capillary as a positive electrode, a copper wire with one end arranged in the capillary, an electrolyte injected into the capillary, and a zinc wire with one end arranged in the other end of the capillary as a negative electrode; The active substance in the active material is MnO2, V2O5, Mn3O4, Co3O4 or LiFePO4; The surface of the copper wire portion disposed in the capillary is coated with silver glue, and the copper wire and the capillary are fixed and sealed by the silver glue; The surface of the zinc wire portion arranged in the capillary is coated with polyimide, and the zinc wire and the capillary are fixed and sealed by ultraviolet light curing glue.

2. The microbattery according to claim 1, characterized in that: The active material includes the active substance, a binder and a conductive agent.

3. The microbattery according to claim 2, characterized in that: The mass ratio of the active material, the binder and the conductive agent is (5-10):1:

1.

4. The microbattery according to claim 3, characterized in that: The binder is polyvinylidene fluoride, polytetrafluoroethylene, polyimide or acrylic acid; the conductive agent is carbon nanotube, granular Super-P, Ketjen black, fibrous vapor-grown carbon fiber, sheet KS-6, SFG-6, graphene or graphite.

5. The microbattery according to claim 4, characterized in that: The binder in the active material film layer is dissolved in N-methylpyrrolidone, acetone or dimethylacetamide to form a binder glue solution, and the mass percentage of the binder in the binder glue solution is 5%-15%.

6. The microbattery according to claim 1, characterized in that: The electrolyte is a ZnSO4 electrolyte, and the concentration of the ZnSO4 electrolyte is 0.5M-1.5M.

7. The microbattery according to claim 1, characterized in that: The capillary is a glass capillary, a plastic capillary or a metal capillary.

8. The microbattery according to claim 1, characterized in that: The inner diameter of the capillary is 0.8-1.5 mm and the length is 1-2 mm.

9. A method for preparing and packaging a microbattery according to any one of claims 1 to 8, characterized in that: The steps include: Dissolving the adhesive in N-methylpyrrolidone, acetone or dimethylacetamide to form an adhesive glue; The active material, the binder glue and the conductive agent are mixed to obtain the active material slurry; The active material slurry is injected into the capillary tube, and after drying, an active material for the positive electrode is formed in the capillary tube; Insert a copper wire coated with silver glue into one end of the capillary tube so that the copper wire contacts the active material, and fix and seal the copper wire and the capillary tube with silver glue; Inject electrolyte into the capillary from the other end of the capillary; Insert a polyimide-coated zinc wire into the active material from the end of the capillary tube injected with electrolyte, and fix and seal the zinc wire and the capillary tube with ultraviolet light curing adhesive.

10. The method for preparing and packaging a micro battery according to claim 9, characterized in that: The drying is to place the capillary in an oven and dry it at 50° C.-100° C. for 1-4 hours until the solvent in the active material slurry is completely volatilized to form active material in the capillary.

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