JPH0548924B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a method for manufacturing an electric double layer capacitor. [Prior Art] A multilayer electric double layer capacitor generally consists of a laminate 21 formed by laminating the required number of electric double layer capacitor elements (hereinafter referred to as basic cells) 22, as shown in FIG. It is composed of an exterior case 25, an insulating case 23 inserted between the laminate 21 and the exterior case 25, and a lead electrode 24 having a metal disk lead terminal protruding in a raised shape. The basic cell 22 of this laminate 21 is, as shown in FIG.
A conductive separator 2 that is electronically conductive and impermeable to ions, a carbon paste electrode 4 made of powdered activated carbon and an electrolyte solution, and a carbon paste electrode 4
It is composed of a non-conductive gasket 11 that holds the paste electrodes and blocks them from the outside world, and a porous separator 6 that is permeable to ions and non-electronic conductive and prevents conduction between the paste electrodes 4. The conventional basic cell 22 as shown in FIG. 3 was formed by the following manufacturing method. That is, the powder is placed in a recess formed by pressing an electronically conductive unvulcanized rubber sheet with no openings onto the bottom surface of an electronically conductive unvulcanized rubber sheet with multiple openings. A carbon paste electrode containing activated carbon and an electrolyte solution as main components is filled, and the pair is combined via a non-electron conductive porous separator. Next, both sides of this are sandwiched between a pair of holding plates such as aluminum plates, pressure is applied through the holding plates, and this state is maintained to vulcanize the unvulcanized rubber sheet and simultaneously bond the rubber sheets together. After shielding and protecting the carbon paste electrode 4 from the external atmosphere, it was cut into a desired shape using a known cutting method to form the basic cell 22 shown in FIG. Furthermore, the basic cell 22
A required number of layers are laminated and crimped to form a laminate 2 of basic cells 22.
It formed 1. [Problems to be Solved by the Invention] The conventional electric double layer capacitor manufacturing method described above has the following drawbacks. (1) A pair of holding plates is required for each unit of one basic cell configuration, and the jig used in the vulcanization process becomes large, making it unsuitable for mass production. (2) It is necessary to uniformly press and hold multiple elements at the same time, which requires a pressurizing mechanism with large output and high precision. [Means for solving the problems] The method for manufacturing an electric double layer capacitor of the present invention includes:
A carbon paste containing powdered activated carbon and an electrolyte solution as main components is applied to the recesses formed by pressing a non-electron conductive unvulcanized rubber sheet with multiple openings onto an electronic conductive unvulcanized rubber sheet. Fill the electrode,
a step of forming a carbon paste electrode filling sheet; a step of combining the carbon paste electrode filling sheet into a pair of upper and lower parts through a non-electron conductive porous separator to form a combined sheet; and forming the combined sheet into an element shape. It includes a step of cutting and laminating a required number of sheets, and a step of vulcanizing the laminate obtained in the previous step while applying pressure from both upper and lower ends. [Example] Next, an example of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view and a side view of a product in each manufacturing process of an embodiment of the method for manufacturing an electric double layer capacitor of the present invention. First, as shown in the left and right pair in Figure 1a,
An electronically conductive unvulcanized butyl rubber sheet 2 containing conductive carbon and having a thickness of 0.2 mm is crimped onto the bottom surface of a non-electron conductive unvulcanized butyl rubber sheet 1 having a thickness of 0.5 mm and having multiple mm holes. A carbon paste electrode 4 made of activated carbon powder with a specific surface area of about 1100 m ² /g (BET method) and a particle size of 300 mesh or less and 30 wt % sulfuric acid was placed in the recess 3 formed using the doctor knife method as shown in Figure 1b. A pair of electrode filling sheets 5 are formed. Next, as shown in FIG. 1c, the pair of electrode filling sheets 5 are combined via a porous separator 6 made of polypropylene with a thickness of about 25 μm to form a combined sheet 7. Next, this is cut and separated into a desired element shape, and eight pieces thereof are laminated to form an unvulcanized element laminate 8. next,
As shown in FIG. 1e, both upper and lower ends of the unvulcanized element laminate 8 are sandwiched between aluminum holding plates 9 with a thickness of 5 mm.
A pressure of 10 kg/cm ² was applied from above and below through the holding plate 9, and while this pressure was maintained, the non-electronically conductive material was left in a thermostat at 120°C for 30 minutes. The vulcanized butyl rubber sheet 1, the unvulcanized butyl rubber sheet 2 manufactured by Electron Conduction Co., Ltd., and the unvulcanized butyl rubber sheet 1 are co-vulcanized and bonded, and the carbon paste electrode 4 is sealed. At the same time, the electronically conductive unvulcanized butyl rubbers of the basic cells 22 that were in contact with each other by lamination were co-vulcanized and adhered to each other, thereby obtaining a vulcanized element laminate (not shown). A metal plate (not shown) with protruding plate-shaped metal terminals for measuring electrical characteristics was applied to both the upper and lower ends of the 10 vulcanized element laminates, and a pressure of 20 kg/cm ² was applied and this pressure was maintained. It was clamped in this state and its electrical characteristics were measured. At that time, for comparison, 10 basic cell laminates 21 of electric double layer capacitors of the same shape formed by the conventional manufacturing method using the same materials and the same shape of the combined sheets as in this example were also manufactured by the same method. When the electrical characteristics were measured, the average values for each were as shown in the table below.

〔Effect of the invention〕

As explained above, the present invention produces the following effects by simultaneously fabricating a plurality of basic cells in sheet form, cutting this into a single element shape, laminating the required number of cells, and then vulcanizing them. Yes, it has great industrial value. (1) Contact resistance between the laminated cells is reduced by co-vulcanizing and adhering the laminated basic cells to each other. (2) Furthermore, since the element stack can be bonded and integrated, the subsequent process of inserting into a case can be easily automated. (3) Since vulcanization is performed one laminated element at a time, the pressurizing force during vulcanization can be reduced, making it possible to simplify the equipment and improving the control accuracy of pressurizing force.

[Brief explanation of the drawing]

Figure 1 is a sectional view and a side view of a product in the manufacturing process for each step of an embodiment of the method for manufacturing an electric double layer capacitor of the present invention, and Figure 1a shows a non-conductive product having a plurality of holes. FIG. 1B is a sectional view of the unvulcanized butyl rubber sheet 1 and the conductive unvulcanized butyl rubber sheet 2 pressed together; FIG. 1B is a sectional view of the recess 3 in FIG. Figure c is a sectional view of the combined sheet 7, Figure 1d is a side view of the unvulcanized element laminate 8, Figure 1e is a side view of the unvulcanized element laminate 8 in a pressurized and vulcanized state, FIG. 2 is a sectional view of a conventional example of an electric double layer capacitor, and FIG. 3 is a sectional view of a conventional example of a basic cell. 1... Non-electron conductive unvulcanized butyl rubber sheet, 2... Electronic conductive unvulcanized butyl rubber sheet, 3... Concave portion, 4... Carbon paste electrode,
5... Electrode filling sheet, 6... Porous separator, 7... Combined sheet, 8... Unvulcanized element laminate, 9... Holding plate.

Claims (1)

[Claims] 1. Powdered activated carbon and an electrolyte are placed in the recesses formed by pressing a non-electron conductive unvulcanized rubber sheet having a plurality of openings onto an electronic conductive unvulcanized rubber sheet. A step of filling a carbon paste electrode containing a solution as a main component to form a carbon paste electrode filling sheet, and combining the carbon paste electrode filling sheet into a pair of upper and lower parts through a non-electronically conductive porous separator to form a combined sheet. A step of forming an electric double layer capacitor, a step of cutting the combined sheet into an element shape and laminating the required number of sheets, and a step of vulcanizing the laminate obtained in the previous step while applying pressure from both upper and lower ends. Production method.