KR20060041559A - Open-typed thin film battery - Google Patents

Abstract

An open type thin film battery includes a separator; A cathode active material layer including a cathode active material layer and a cathode active material layer disposed on both sides of the separator and containing a cathode active material; A thin film current collector layer disposed outside the positive electrode active material layer and the negative electrode active material layer; And an electrically insulating outer film layer disposed outside the thin film current collector layer. The separator does not contain water or an electrolyte and is formed so that water or an electrolyte may flow from the outside during its use.

Thin Film, Film, Electrolyte, Battery

Description

Open Thin Film Battery {OPEN-TYPED THIN FILM BATTERY}

1 is a perspective view of an open type thin film battery according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the open type thin film battery of FIG. 1.

3 is a perspective view of an open type thin film battery according to another embodiment of the present invention.

4 is an exploded perspective view of the open-type thin film battery of FIG. 3.

The present invention relates to an open type thin film battery.

In general, a battery means a device that converts chemical energy generated during electrochemical oxidation-reduction reaction of chemical substances into electrical energy, and is disposed of when the energy in the battery is depleted according to its use characteristics. It can be divided into a primary battery to be recharged and a rechargeable battery that can be reused many times while being continuously charged.

The main forms of the primary battery are cylindrical, prismatic, and button type. Conventional primary batteries have been mainly used as energy sources such as watches, remote controllers, cassettes, lanterns, etc., but recently, digital cameras, wireless keyboards, MP3 players, CD players, door lock systems ( It is being used as an energy source for new devices such as door lock systems. These types of batteries can be divided into manganese batteries, alkaline batteries, mercury batteries, silver batteries, lithium batteries, air zinc batteries, etc., depending on the type of positive electrode, negative electrode, and electrolyte. These cells can have high capacities from as little as several tens of mAhr up to hundreds of Ahr. These primary batteries are an important technical issue (extension of life), many researches on this.

On the other hand, in order to be used in liquid crystal display, electronic calculator, IC card, temperature sensor, pressure sensing buzzer, or iontophoresis device for drug delivery, small thin film battery that can consume and dispose only the required current capacity for the purpose The need for this is emerging.

Thin film batteries can be classified into two types. The first type is a thin film battery containing a liquid electrolyte (ie, a liquid battery), and the second type is a thin film battery containing a solid electrolyte. Solid electrolytes generally have the advantage of preventing evaporation or leakage of electrolyte solution by dissolving hydrophilic polymers in water to increase the viscosity of liquid electrolytes. Because the rate of diffusion is limited, its operation is highly dependent on temperature and in many cases it is usually well to work well only at high temperatures. The limited diffusion rate of ions in the thin film battery using the solid electrolyte causes a low ratio of the generated electric energy to its potential chemical energy, and thus has a large disadvantage compared to liquid batteries.

In general, a thin film battery includes an outer film layer, a thin film current collector layer, a positive / negative electrode active material layer, and a separator layer including an electrolyte solution.

The separator layer includes an electrolyte solution, and the positive and negative electrode active material layers are disposed on both sides of the separator layer, respectively, the positive electrode active material layer contains a positive electrode active material, and the negative electrode active material layer contains a negative electrode active material. The thin film current collector layer is disposed outside the positive / negative electrode active material layer and is formed of a metal foil, a conductive carbon film in the form of a thin film, a conductive carbon ink or a conductive carbon paste on the insulating film. (conductive carbon paste) may be a screen printed or coated layer. The outer film layer includes a sealed type and an open type depending on whether the inside of the battery is isolated from the outside, and the film layer should basically have excellent electrical insulation and no gas permeation. The outer film layer having this feature may be formed of a single layer or a composite layer.

However, the general thin film battery configured as described above has the advantage of being applied to various fields requiring a thin current by calculating the current capacity according to the intended use by implementing a thin film, while using a low current capacity and a thin film type material. The problem of preservation of performance due to the decrease of current capacity during long-term storage due to spontaneous self-discharge and the pressure caused by internal gas generation, and in the case of non-closed type, through external film and sealing part Performance stability due to long-term storage is a problem due to a problem of deterioration caused by evaporation or loss of electrolyte solution.

The present invention has been made to solve the above-mentioned problems, and an object thereof is to provide an open thin film battery which can minimize the loss of current capacity even when stored for a long time.

An open type thin film battery according to an embodiment of the present invention for achieving the above object, a separator (separator); A cathode active material layer including a cathode active material layer and a cathode active material layer disposed on both sides of the separator and containing a cathode active material; A thin film current collector layer disposed outside the positive electrode active material layer and the negative electrode active material layer; And an electrically insulating outer film layer disposed outside the thin film current collector layer. The separator does not contain water or an electrolyte and is formed so that water or an electrolyte may flow from the outside during its use.

In order to introduce water or an electrolyte, an injection hole through which water or an electrolyte may be introduced may be formed in the outer film layer, and the separator may be formed larger than the outer film layer so that a part of the separator is exposed to the outside. .

The outer film layer may be formed of an insulating film of a single layer or a composite layer.

The thin film current collector layer may be formed of a conductive metal or conductive carbon.

The cathode active material may include any one of conductive carbon, manganese dioxide, lead dioxide, nickel oxide, silver oxide, and copper oxide.

The negative active material may include any one of zinc, iron, magnesium, aluminum, cadmium, lead, and tin.

The separator may be formed of any one or more of cellulose paper, vinylon, pulp, filter paper, and nonwoven fabric.

The electrolyte may include any one or more of ammonium chloride, zinc chloride, sulfuric acid, lead sulfide, manganese sulfide, calcium hydroxide, and sodium hydroxide.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

1 and 2, an open type thin film battery 100 according to an embodiment of the present invention includes a separator 101 and a cathode active material layer 103 disposed on both sides of the separator 101, respectively. A pair of thin film collector layers 107 disposed on the outside of the negative electrode active material layer 105, the positive electrode active material layer 103, and the negative electrode active material layer 105, and a pair of the pair disposed on the outside of the thin film collector layers 107. An outer film layer 109.

According to the embodiment of the present invention, the separator 101 of the open-type thin film battery in the finished state does not contain water or an electrolyte, and is formed so that water or an electrolyte may flow into the separator 101 from the outside during use.

According to one embodiment of the present invention, as shown in FIG. 1, an injection hole 111 through which water or an electrolyte may flow into the outer film layer 109 is formed. Just before using a thin film battery, water or electrolyte solution is inject | poured through this injection port 111, and a thin film battery can be used.

The separator 101 may be formed of any one or more of cellulose paper, vinylon, pulp, filter paper, and nonwoven fabric.

The positive electrode active material layer 103 contains a positive electrode active material, and the positive electrode active material includes conductive carbon, manganese dioxide (MnO 2), lead dioxide (PbO 2), nickel oxide (NiO), and silver oxide (silver oxide). AgO), copper oxide (copper oxide, CuO) may include any one.

The negative electrode active material layer 105 contains a negative electrode active material, and the negative electrode active material is zinc, iron, magnesium, aluminum, cadmium, lead, and tin. It may include any one of).

The thin film collector layer 107 disposed outside the positive electrode active material layer 103 and the negative electrode active material layer 105 may be formed of a conductive metal or conductive carbon.

The thin film current collector layer 107 may be in the form of a foil such as copper, zinc, aluminum, or nickel, or a conductive carbon film or conductive carbon on a thin film conductive carbon film or insulating film. The conductive carbon paste may be a screen printed or coated layer.

The electrically insulating outer film layer 109 disposed outside the thin film current collecting layer 107 may be formed of an insulating film of a single layer or a composite layer.

For example, the outer film layer 109 may be formed of polyethylene, polypropylene, polyolefine, polyvinyl chloride, polyester, and polyethylene naphthalate. It can be formed by using any one of, polyimide, and nylon (nylon) as the main raw material. On the other hand, when the outer film layer 109 is formed of a composite layer, an aluminum layer or the like is laminated on a polyolefine film having excellent sealing properties or a polyester film having excellent insulation. It can be set as the film which laminated the nylon layer.

The electrolyte flowing into the separator 101 of the open-type thin film battery 100 is ammonium chloride, zinc chloride, sulfuric acid, lead sulfide, manganese sulfide. It may include any one or more of calcium hydroxide, calcium hydroxide, and sodium hydroxide.

For example, the thin film current collector layer 107 may be a layer formed on the outer film layer 109 by filming by a method such as foil form, printing, or coating. In addition, the cathode active material layer 103 and the anode active material layer 105 may be coated on the thin film current collector layer 107 through printing, coating, and casting to form an active material layer of a thin film. The thin film battery may be assembled by attaching the active material layer thus formed by thermal bonding or various bonding methods based on the separator.

As shown in FIGS. 3 and 4, the open-type thin film battery 200 according to another embodiment of the present invention includes a separator active material layer 203 disposed on both sides of the separator 201 and the separator 201, respectively. ) And a pair of thin film collector layers 207 and outer sides of the thin film collector layer 207 that are disposed outside the cathode active material layer 205, the cathode active material layer 203, and the anode active material layer 205, respectively. A pair of outer film layers 209.                     

The separator 201 of the open-type thin film battery in a finished state does not contain water or an electrolyte, and is formed so that water or an electrolyte may flow into the separator 201 from the outside during use. In the present embodiment, the separator 201 is formed larger than the outer film layer 109, so that a part of the separator 201 is exposed to the outside in the assembled state as shown in FIG. Therefore, water or electrolyte can be introduced into the thin film battery 200 by soaking water or electrolyte in the exposed portion of the separator 201 immediately before use, and as a result, the state in which the thin film battery 200 can be used is do.

3 and 4, the remaining part of the thin film battery according to the embodiment of the present invention is the same as in the above-described embodiment, and thus description thereof will be omitted.

That is, in the conventional thin film battery, since the separator contains an electrolyte solution from the time of its manufacture, a fine chemical reaction of the electrolyte is inevitably generated until the actual thin film battery is used, and thus the life and durability of the thin film battery are deteriorated. However, according to the embodiment of the present invention, the separator of the first manufactured thin film battery does not contain an electrolyte solution, and the electrolyte or water is introduced into the separator immediately before use so that the life of the thin film battery can be prevented from being reduced by the progress of the fine reaction of the electrolyte solution. It becomes possible.

Hereinafter, the performance stability of the disposable thin film battery according to the embodiment of the present invention as described above through the experimental example.

Experimental Example 1

After screen printing or coating a conductive paste on a 50 μm-thick polyvinyl chloride, and sufficiently drying in an oven at 80 ° C. for at least 2 hours, a thin film current collector is prepared. In the% polyacrylic acid and the positive electrode, 30 g of manganese dioxide, 5 g of conductive carbon, and 10 g of 20% polyacrylic acid were evenly mixed and applied to the current collector at 2 × 3 cm, and then dried sufficiently in an oven at 80 ° C. for at least 2 hours. Prepare the positive and negative electrodes. Here, an electrolyte solution of 16.8 g of chlorine-chloride was dissolved in 12 g of water and completely wetted by a filter paper strip or immersed, and then taken out, cut into a size of 2.5 × 3.5 cm, and prepared by using an adhesive. After measuring the voltage, it maintained a voltage of 1.5 ± 0.02V.

Experimental Example 2

After assembling using an electrolyte solution in which 8.4 g of ammonium chloride was dissolved in 12 g of water among the components of the electrolyte solution in the same manner as described in Experimental Example 1, the voltage was measured. Maintained.

Experimental Example 3

After assembling using an electrolyte solution in which 0.3 g of potassium hydroxide was dissolved in 12 g of water among the components of the electrolyte solution as described in Experimental Example 1, the voltage was measured, and the voltage was maintained at 1.5 ± 0.015 V. .

Experimental Example 4

After assembling using 30% sulfuric acid solution among the components of the electrolyte as the electrolyte by the method as described in Experimental Example 1, the voltage was measured, and the voltage was maintained at 2.0 ± 0.035V.                     

Comparative Example 1

Screen-print or coat a conductive paste on 50 μm thick polyvinyl chloride, dry it sufficiently for at least 2 hours in an oven at 80 ° C, and prepare a thin film current collector. 30 g of zinc powder for cathode, 20 g of polyacrylic acid, and 30 g of manganese dioxide for anode And 5 g of conductive carbon and 10 g of 20% polyacrylic acid were evenly applied to the current collectors at 2 × 3 cm, and then sufficiently dried in an oven at 80 ° C. for at least 2 hours to prepare a positive electrode and a negative electrode, respectively. Then, the electrolyte solution of 16.8 g of chlorine-chloride was dissolved in 12 g of water, and then completely wetted by a filter paper strip or immersed, and then removed from the oven at 80 ° C. until dryness was completely removed after about 1 hour. The cut was prepared in the size of cm, these were assembled using an adhesive, and the voltage was measured. The voltage was not caught by the measuring device.

Comparative Example 2

In the same manner as described in Comparative Example 1, filter paper, in which none of the components of the electrolyte were buried, was cut to a size of 2.5 × 3.5 cm, prepared, assembled with an adhesive, and the voltage was measured. It was not caught by the measuring device.

A thin film battery was prepared through the above experimental and comparative examples, and the current capacity was changed after being left at room temperature [Table 1], 30 ° C [Table 2], 45 ° C [Table 3], and 60 ° C [Table 4] for a certain period of time. Is as follows.                     

Table 1

[Table 2]

Table 3

Table 4

In the above, when looking at the results of [Table 1] to [Table 4] for the temperature and period-by-period change of the current capacity according to the experimental example and the comparative example of the present invention, the current of Comparative Example 1 and Comparative Example 2 that does not contain an electrolyte solution It is possible to obtain a result that the storage life with respect to the capacity is excellent.

In the above, preferred embodiments of the present invention have been described, but the present invention is not limited to the above embodiments, and easily changed by those skilled in the art to which the present invention pertains. It includes all changes and / or modifications to the extent deemed acceptable.

According to the embodiment of the present invention as described above, since the separator is stored in a state that does not contain water or an electrolyte, and may be water or an electrolyte immediately before use, a current that may occur when stored for a long time in an electrolyte state Loss of capacity can be prevented.

Claims (9)

A separator; A cathode active material layer including a cathode active material layer and a cathode active material layer disposed on both sides of the separator and containing a cathode active material; A thin film current collector layer disposed outside the positive electrode active material layer and the negative electrode active material layer; An open type thin film battery comprising an electrically insulating outer film layer disposed outside the thin film current collector layer, The separator does not contain water or an electrolyte and is formed so that water or an electrolyte may be introduced from the outside during its use. In claim 1, An open type thin film battery in which an injection hole through which water or an electrolyte may be introduced is formed in the outer film layer. In claim 1, The separator is formed larger than the outer film layer so that a portion of the separator is exposed to the outside. In claim 1, The outer film layer is an open type thin film battery formed of an insulating film of a single layer or a composite layer. In claim 1, The thin film current collector layer is formed of a conductive metal or conductive carbon. In claim 1, The cathode active material is an open-type thin film battery including any one of conductive carbon, manganese dioxide, lead dioxide, nickel oxide, silver oxide, and copper oxide. In claim 1, The anode active material is an open thin film battery including any one of zinc, iron, magnesium, aluminum, cadmium, lead, and tin. In claim 1, The separator is an open-type thin film battery formed of any one or more of cellulose paper, vinylon, pulp, filter paper, and nonwoven fabric. In claim 1, The electrolyte solution is an open-type thin film battery comprising any one or more of ammonium chloride, zinc chloride, sulfuric acid, lead sulfide, manganese sulfide, calcium hydroxide, and sodium hydroxide.

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