A cage-type electrode for a secondary battery and a manufacturing method thereof

Abstract

The present invention discloses a method for manufacturing a cage-type electrode for a secondary battery. This method involves pressing conductively treated organic particles between a recessed container and a cover plate, each made of porous metal foam. The recessed container can hold a large amount of active material and prevent loss of the active material during the pressing process, thereby ensuring a high capacity per unit area of the resulting electrode. This method is simple, reliable, and low-cost, and can significantly increase the capacity per unit area of the electrode.

Description

Technical Field

[0001] The present invention relates to the technical field of electrochemical energy storage devices, and in particular to a cage-type electrode for a secondary battery and a manufacturing method thereof. Background Art

[0002] Organic molecules that undergo electrochemical reactions in aqueous electrolytes have two drawbacks: first, their density is generally much lower than that of inorganic molecules (such as nickel, iron, aluminum, cadmium, zinc, lead, and manganese); second, organic molecules are poor conductors of electrons and generally need to be combined with conductive materials such as carbon, resulting in an even lower density. Consequently, electrode fabrication is quite difficult and challenging to form.

[0003] Conventional methods for producing aqueous battery electrodes typically include slurry drawing, impregnation, coating, and electrodeposition. However, due to the low density of organic molecules and their non-normal particle size distribution, these traditional methods struggle to effectively produce electrodes with high area-density capacity.

[0004] This is because in the existing production method, the synthesized slurry has a low solid content, and the solvent needs to be evaporated when making the electrode plate. This causes a large shrinkage rate of the material, resulting in the electrode being very thin and extremely unevenly distributed. Therefore, the capacity per unit area is also very small, which is only suitable for electrode research and is not suitable for the production of high-area-capacity and low-cost batteries. Summary of the Invention

[0005] The object of the present invention is to provide a cage-type electrode for a secondary battery and a method for manufacturing the same, which can produce a cage-type electrode with high area capacity at relatively low cost.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] A method for manufacturing a cage electrode for a secondary battery comprises filling a conductively treated active material composed of organic particles into a groove container made of a first porous foam metal, then covering it with a cover plate made of a second porous foam metal, and then sequentially performing pressing, impregnation with an adhesive, drying, and installing a tab.

[0008] The groove container is a groove cage box, and the pressing is performed by a roller. The pressing direction is the arrangement direction of the groove container and the cover plate. The tabs are installed by welding, and the conductive treatment is to compound the organic particles with the conductive material.

[0009] Since the particle size of some active substances is smaller than the diameter of the porous mesh of the porous metal foam, by impregnating the electrode with an adhesive, it is possible to prevent organic particles from falling off from the mesh of the porous mesh during the charge and discharge process of the electrode, causing the battery life to continue to decline during the charge and discharge cycle.

[0010] Preferably, the tap density of the active substance is 0.1-1.0 g / cm 3 .

[0011] Preferably, the first porous metal foam is composed of at least one of porous nickel foam, porous iron foam, and porous copper foam, and the first porous metal foam has a pore size of 50-200 PPI, a maximum thickness of 1-10 mm, a bottom thickness of 0.2-2.0 mm, and a surface density of 50-400 g / m 2 The maximum thickness here refers to the overall thickness of the side wall and bottom of the first porous metal foam.

[0012] Preferably, the second porous metal foam is composed of at least one of porous nickel foam, porous iron foam, and porous copper foam, and the second porous metal foam has a pore size of 50-200 PPI, a thickness of 0.2-2.0 mm, and an area density of 50-400 g / m 2 .

[0013] The first porous metal foam and the second porous metal foam are both porous metal mesh structures. After rolling, the first porous metal foam is firmly combined with the lower surface of the second porous metal foam through the top of its groove wall, which can effectively prevent the two from falling off each other.

[0014] Preferably, the thickness compression ratio of the pressing is 1.1-2.0 times.

[0015] Preferably, the adhesive is a first solution with a solid content of 2-20% obtained by diluting polytetrafluoroethylene latex, or a second solution with a solid content of 2-20% obtained by diluting styrene-butadiene rubber latex.

[0016] Preferably, the immersion time is 1-600s.

[0017] Preferably, the drying temperature is 60-200° C., and the drying time is 2-120 min. Drying is performed until a layer of white adhesive appears on the surface of the electrode.

[0018] Preferably, the tab is made of nickel or nickel-plated steel strip, and the thickness of the tab is 0.04-2.0 mm.

[0019] A cage-type electrode for a secondary battery is manufactured by the above-mentioned method for manufacturing a cage-type electrode for a secondary battery.

[0020] Due to the application of the above technical solution, the present invention has the following advantages over existing technologies: A cage-type electrode for a secondary battery and a method for manufacturing the same, wherein conductively treated organic particles (i.e., active material) are pressed between a recessed container and a cover plate, each made of porous metal foam. The recessed container can support a large amount of active material and prevent loss of the active material during the pressing process, resulting in an electrode with a large capacity per unit area. This method is simple, reliable, and low-cost, and can significantly increase the capacity per unit area of the electrode. DETAILED DESCRIPTION

[0021] The technical solution of the present invention is further described below with reference to specific embodiments.

[0022] Hereinafter, only certain exemplary embodiments are briefly described. As will be appreciated by those skilled in the art, the described embodiments may be modified in various ways without departing from the spirit or scope of the embodiments of the present invention. Therefore, the description is to be regarded as illustrative in nature and not restrictive.

[0023] In the description of the embodiments of the present invention, it should be understood that the terms "length", "inside", etc. indicating orientation or positional relationships are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the embodiments of the present invention.

[0024] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0025] In the embodiments of the present invention, unless otherwise expressly specified or limited, the terms "installed," "connected," "connected," "fixed," etc. should be understood in a broad sense. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of the present invention based on specific circumstances.

[0026] In the embodiments of the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature includes the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0027] The disclosure below provides many different embodiments or examples for implementing different structures of the embodiments of the present invention. In order to simplify the disclosure of the embodiments of the present invention, the components and configurations of specific examples are described below. Of course, these are merely examples and are not intended to limit the embodiments of the present invention. In addition, the embodiments of the present invention may repeat reference numerals and / or reference letters in different examples. Such repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or configurations discussed.

[0028] Example 1:

[0029] Negative electrode for organic aqueous electrolyte: The material of the groove container is porous nickel foam with a depth of 2mm, a bottom thickness of 0.8mm, and a surface density of 180g / m 2 , pore size is 110PPI; organic particles are phenazine, which is compounded with carbon materials to obtain active materials. The specific capacity of the active material is 210mAh / g and the tap density is 0.45g / cm 3 The cover material is porous nickel foam, with a thickness of 0.8 mm and a surface density of 180 g / m 2 The pore size is 110PPI; the rolling thickness compression ratio is 1.5; the electrode is impregnated with a polytetrafluoroethylene emulsion with a solid content of 10% for 30 seconds, the drying temperature is 90°C, and the drying time is 20 minutes; after the electrode is spot-welded, its area capacity is 16mAh / cm 2 .

[0030] Comparative Example 1:

[0031] Anode for organic aqueous electrolyte: The carrier is a single-layer porous nickel foam material with a surface density of 280g / m 2 The thickness is 1.5mm, the pore size of the porous nickel foam is 110PPI, the active material is a composite of phenazine and carbon material, its specific capacity is 210mAh / g, and the tap density is 0.45g / cm 3The active material was mixed with pure water, thickener CMC (2%), and binder polytetrafluoroethylene emulsion (solid content 60%) in a mass ratio of 100:1400:75:4.2 to form a fluid slurry. The slurry was then impregnated into a carrier using a slurry pulling method. The carrier was then dried in a drying furnace and rolled to a compression ratio of 1.5. After the electrode was manufactured, its area capacity was 1.68 mAh / cm 2 .

[0032] According to the above data, the area capacity of the electrode prepared in Example 1 is about 10 times that of the electrode prepared in Comparative Example 1. The method of the present invention not only has simpler and more reliable process steps, but also greatly improves the unit area capacity of the electrode.

[0033] The above embodiments are only for illustrating the technical concept and features of the present invention. Their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for manufacturing a cage electrode for a secondary battery, characterized in that: First, the organic particles are compounded with the conductive material to obtain the active material, and then the active material is filled into the groove container made of the first porous foam metal, and then covered with a cover plate made of the second porous foam metal, and then pressed, impregnated with adhesive, dried and installed with the tabs in sequence.

2. The method for manufacturing a cage electrode for a secondary battery according to claim 1, wherein: The tap density of the active material is 0.1-1.0 g / cm 3 .

3. The method for manufacturing a cage electrode for a secondary battery according to claim 1, wherein: The first porous foam metal is composed of at least one of porous foam nickel, porous foam iron, and porous foam copper. The first porous foam metal has a pore size of 50-200 PPI, a maximum thickness of 1-10 mm, a bottom thickness of 0.2-2.0 mm, and a surface density of 50-400 g / m 2 .

4. The method for manufacturing a cage electrode for a secondary battery according to claim 1, wherein: The second porous foam metal is composed of at least one of porous foam nickel, porous foam iron, and porous foam copper. The second porous foam metal has a pore size of 50-200 PPI, a thickness of 0.2-2.0 mm, and a surface density of 50-400 g / m 2 .

5. The method for manufacturing a cage electrode for a secondary battery according to claim 1, wherein: The thickness compression ratio of the pressing is 1.1-2.0 times.

6. The method for manufacturing a cage electrode for a secondary battery according to claim 1, wherein: The adhesive is a first solution with a solid content of 2-20% obtained by diluting polytetrafluoroethylene latex, or a second solution with a solid content of 2-20% obtained by diluting styrene-butadiene rubber latex.

7. The method for manufacturing a cage electrode for a secondary battery according to claim 1, wherein: The immersion time is 1-600s.

8. The method for manufacturing a cage electrode for a secondary battery according to claim 1, wherein: The drying temperature is 60-200°C and the drying time is 2-120 minutes.

9. The method for manufacturing a cage electrode for a secondary battery according to claim 1, wherein: The tab is made of nickel or nickel-plated steel strip, and the thickness of the tab is 0.04-2.0 mm.

10. A cage electrode for a secondary battery, produced by the method for producing a cage electrode for a secondary battery according to any one of claims 1 to 9.