JP2007287461A - Formation method of functional film, formation method of electrode, and manufacturing method of secondary battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a formation method of a functional film capable of forming a functional film in accordance with an intended pattern without causing bleed in a boundary of the pattern; to provide a formation method of an electrode using the method; and to provide a manufacturing method of a secondary battery forming an electrode the method. <P>SOLUTION: This formation method of a functional film is used for forming the functional film having a predetermined pattern by sequentially applying, to a surface of a base body, two or more kinds of compositions for functional film formation each containing a functional material and an organic solvent by a droplet discharging device. The formation method of a functional film is characterized by comprising a process for applying one of the compositions to the surface of the base body to form a coating film of the composition, and thereafter drying the coating film of the composition before applying the next composition. This formation method of an electrode is used for forming an electrode layer containing two or more kinds of electrode layer formation materials by the method. In this manufacturing method of a secondary battery having a negative electrode, an electrolyte and a positive electrode, the positive electrode is formed by the formation method of an electrode. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a functional film forming method for forming a functional film having a predetermined pattern by applying two or more kinds of functional materials on a substrate using a droplet discharge device, and an electrode forming method using this method ,
The present invention also relates to a method for manufacturing a secondary battery using this electrode forming method.

In recent years, electric vehicles (EV), hybrid vehicles (HEV), fuel cell vehicles (FCV)
) Has been put to practical use, the development of batteries serving as power sources for these automobiles has been carried out at a rapid pace. Such batteries are required to have extremely strict conditions such as being able to be repeatedly charged and discharged, and capable of realizing high output and high energy density. In order to satisfy these requirements, a thin laminate battery in which a plate-like positive electrode and a negative electrode are accommodated in an outer container and a liquid electrolyte is enclosed is manufactured, and many of them are connected in series and in parallel. Has been proposed (Patent Document 1, etc.).

When such a battery is used as a power source for a vehicle or the like that requires high output, it is necessary to connect a large number of batteries in series, so that the thickness of the electrode needs to be further reduced.

As a method for forming a thin electrode, for example, in Patent Documents 2 to 4, etc., the electrode layer forming composition is ejected as droplets onto a substrate, and the droplets are attached to the substrate. There has been proposed a method of forming an extremely thin electrode layer using an inkjet method (a method using a droplet discharge device).

In Patent Document 4, a plurality of electrode layer forming compositions each containing an active material or a conductive material with different electrical characteristics are used according to a pattern designed in advance using a droplet discharge device. A technique for imparting desired charge / discharge characteristics to an electrode of a secondary battery by coating on a substrate is disclosed.

JP2003-151526A JP 2005-11656 A JP 2005-11657 A JP 2005-135599 A

With the recent reduction in size and thickness of secondary batteries, the electrode layer is also required to form a fine pattern.
However, in the conventional method using a droplet discharge device, when droplets of different types of compositions are applied close to each other, bleeding occurs at the boundary, the pattern is broken, and the pattern cannot be formed as intended. There was a problem.

The present invention has been made in view of such circumstances, and a functional film forming composition containing two or more functional materials and an organic solvent is sequentially applied onto a substrate by a droplet discharge device. And
In a functional film forming method for forming a functional film having a predetermined pattern, a functional film forming method capable of forming a functional film according to an intended pattern without blurring of a pattern boundary is applied, and this functional film forming method is applied. It is an object of the present invention to provide a method for forming an electrode to be formed and a method for manufacturing a secondary battery in which a positive electrode is formed by the method for forming the electrode.

In order to solve the above-mentioned problems, the present inventors sequentially applied two or more types of electrode layer-forming materials and an electrode layer-forming composition containing an organic solvent on the same plane of the current collector using a droplet discharge device. Apply,
We have intensively studied the electrode forming method for forming an electrode layer having a predetermined pattern on the same plane. As a result, when the two or more electrode layer forming compositions are sequentially applied on the current collector in accordance with a pre-designed application pattern, one electrode layer forming composition is applied to the composition. After forming the coating film, before applying the next electrode layer forming composition, by performing an operation of drying the coating film of the one electrode layer forming composition, the boundary of the pattern does not blur. The inventors have found that an electrode layer having an intended pattern can be efficiently formed, and have completed the present invention.

Thus, according to the first aspect of the present invention, there is provided a method for forming a functional film described in the following (1) and (2).
(1) A functional film for forming a functional film having a predetermined pattern by sequentially applying a functional film forming composition containing two or more functional materials and an organic solvent on a substrate by a droplet discharge device. A method of forming a functional film-forming composition on a substrate to form a coating film of the composition and then applying the functional film-forming composition before applying the functional film-forming composition. A method for forming a functional film, comprising the step of drying the coating film of the composition for forming a functional film.

(2) A functional film forming composition containing two or more functional materials and an organic solvent is sequentially applied on the same plane of the substrate by a droplet discharge device to have a predetermined pattern on the same plane. A functional film forming method for forming a functional film, wherein a functional film forming composition is applied on the same plane of the substrate to form a coating film of the composition, and then the next functional film is formed. Before applying the composition for
A method for forming a functional film, comprising the step of drying the coating film of the one functional film-forming composition.

According to the method for forming a functional film of the present invention, even when different functional materials are applied in close proximity (adjacent) by a droplet discharge device according to a predetermined application pattern, the boundary Bleeding does not occur, the pattern does not break, and a functional film according to the intended pattern can be formed.

According to 2nd of this invention, the formation method of the electrode as described in following (3)-(5) is provided.
(3) On the current collector, two or more kinds of electrode layer forming materials and an electrode layer forming composition containing an organic solvent are sequentially applied by a droplet discharge device to form an electrode layer having a predetermined pattern. A method of forming an electrode, comprising the steps of: forming the electrode layer by applying one electrode layer forming composition on the current collector and applying the electrode layer forming composition coating After forming, before apply | coating the next composition for electrode layer formation, the formation method of the electrode characterized by including the operation which dries the coating film of said one electrode layer formation composition.

(4) On the same plane of the current collector, two or more kinds of electrode layer forming materials and an electrode layer forming composition containing an organic solvent are sequentially applied by a droplet discharge device. A method of forming an electrode comprising a step of forming an electrode layer having a pattern, wherein the step of forming the electrode layer comprises applying one electrode layer forming composition on the same plane of the current collector. After forming the coating film for the electrode layer forming composition and before applying the next electrode layer forming composition, the method further comprises drying the coating film for the one electrode layer forming composition. A method for forming an electrode.

(5) As the two or more electrode layer forming compositions, at least one positive electrode active material and a first
And a composition containing at least one kind of conductive material and a composition containing a second organic solvent to form a positive electrode of a secondary battery (3) Or the formation method of the electrode as described in (4).

According to the electrode forming method of the present invention, it is possible to form an electrode having an electrode layer having a uniform film thickness according to the intended pattern without blurring at the boundary of the pattern.

According to a third aspect of the present invention, there is provided a positive electrode comprising a negative electrode, an electrolyte, and a current collector, and a positive electrode layer formed on the current collector and containing two or more kinds of positive electrode forming materials. There is provided a method for manufacturing a secondary battery, wherein the positive electrode is formed by the electrode forming method of the present invention.

According to the method for producing a secondary battery of the present invention, an electrode having an electrode layer without pattern distortion can be produced, and thus a large-capacity secondary battery having desired charge / discharge characteristics can be obtained.

Hereinafter, the present invention will be described in detail.
1) Method for Forming Functional Film In the method for forming a functional film of the present invention, a functional film forming composition containing two or more functional materials and an organic solvent is sequentially applied onto a substrate by a droplet discharge device. A functional film forming method for forming a functional film having a predetermined pattern, wherein a functional film forming composition is applied on the substrate to form a coating film of the composition. Before applying the functional film forming composition, a step of drying the coating film of the one functional film forming composition is provided.

Here, the “pattern” is designed to which region on the substrate each of two or more kinds of functional materials having different functions is attached. The pattern is designed semi-empirically to obtain a functional film having the desired functional characteristics. Here, the functional characteristics are, for example, charge / discharge characteristics of a secondary battery having the positive electrode layer when the functional film is a positive electrode layer of the positive electrode of the secondary battery.

The functional film forming method of the present invention is a functional film in which two or more functional film forming compositions are discharged onto a substrate by a droplet discharge device to form a functional film made of two or more functional materials. It is the formation method.

In the method for forming a functional film of the present invention, a functional film forming composition containing two or more functional materials and an organic solvent is sequentially applied on the same plane of a substrate by a droplet discharge device, and the same plane is formed. This is particularly suitable when a functional film having a predetermined pattern is formed thereon.

In the present invention, an ink jet type droplet discharge device is used as means for applying the functional film forming composition.
The discharge method of the droplet discharge device to be used is not particularly limited as long as it is a so-called inkjet method, for example, a thermal method in which bubbles are generated by heating and foaming, and droplets are discharged.
Examples include a piezo method that discharges droplets by compression using a piezo element.

The volume of the droplets discharged in the droplet discharge device is preferably in the range of 1 to 100 picoliters.
According to the ink jet method, since the uniformity of the formed film thickness is very high, a highly uniform film thickness can be maintained even when the same pattern is laminated many times.

A schematic diagram of an example of a droplet discharge apparatus used in the present invention is shown in FIG. Liquid droplet ejection apparatus 1 shown in FIG.
0 is a computer 100, an input terminal 102 connected to the computer 100,
A display 104, a storage device 103, and a discharge nozzle 106 are provided.

The computer 100 includes a drawing unit 101. The drawing unit 101 draws a pattern based on information input from the input terminal 102.
The display 104 displays the pattern drawn by the computer 100 in color.
The storage device 103 stores pattern information (pattern information) finally generated by the computer 100.

The discharge nozzle 106 includes a composition containing a first functional material and an organic solvent (hereinafter “composition A”).
”) Is mounted.

In this embodiment, a droplet discharge device that discharges only the composition A is used. However, a droplet discharge device that discharges two or more types of compositions containing a functional material and an organic solvent in a single unit. An apparatus can also be used. In this case, the container 105 is separated for each composition, and a container connected to a dedicated discharge nozzle 106 assigned to each composition is used. Also,
The container 105 is preferably provided with a stirrer and a heater as necessary.

The computer 100 drives different discharge nozzles according to the graphic drawn in the pattern.
The discharge nozzle 106 discharges the composition A onto the substrate 107 according to the pattern information stored in the storage device 103.

A flow chart showing the procedure of the method for forming a functional film according to the present invention is shown in FIG.
First, information necessary for drawing a pattern is input from the input terminal 102 to the computer 100. This information includes specification of the pattern shape, specification of the size of each pattern, specification of the arrangement location of each pattern, specification of the color of each pattern, and the like.

The drawing unit 101 of the computer 100 draws a pattern based on the input information (S
1) The pattern is displayed on the display 104. The displayed pattern information is stored in the storage device 103 (S2).

In this pattern information, the pattern of the composition A (first functional material pattern) and the pattern of the composition B (second functional material pattern) are formed in any region on the same plane. It is information about.

The computer 100 accesses the storage device 103 and retrieves the stored pattern information (S3).
According to the extracted pattern information, the composition A is discharged (applied) as droplets from the discharge nozzle to a predetermined region on the prepared substrate to form a pattern of the first functional material (S4).
).

After the discharge of the composition A is completed, the coating film of the composition A is dried (S5). After forming the coating film of composition A, before applying composition B, by providing a step of drying the coating film of composition A, different functional materials are brought into close proximity (adjacent). Even when the composition B containing is applied, the boundary does not bleed, the designed pattern is not broken, and a functional film according to the intended pattern can be formed.

Although the method of drying the coating film of the composition A will not be restrict | limited if it is the temperature from which the organic solvent contained in the composition A is dried and removed, Usually, it is about 20-100 degreeC.

Moreover, the pressure when drying the coating film of the composition A is not particularly limited, and may be under atmospheric pressure or under reduced pressure. When drying under reduced pressure, the degree of reduced pressure is a pressure at which the boiling point of the organic solvent used in the composition is 10 to 30 ° C, preferably 15 to 25 ° C.

Moreover, the time for drying the coating film of the composition A is not particularly limited, and may be a time sufficient for the solvent contained in the composition to be removed by drying. Usually 10 seconds to 10 minutes, preferably 3
0 seconds to 3 minutes.

Next, in accordance with the extracted pattern information, the composition B is discharged (applied) as droplets from a discharge nozzle to a predetermined region of the substrate to form a pattern of the second functional material (
S6).

Next, by heating and drying the substrate on which the pattern of the second functional material is formed (
S7), a functional film having a predetermined pattern can be formed.

In the present invention, the application order of the composition A and the composition B is not particularly limited, but the composition A
Of the compositions B, it is preferable to apply the composition having the smaller application area first.

By doing in this way, after completion | finish of discharge of the composition A mentioned above, combined with the effect by performing the operation which dries the coating film of the composition A, and the droplets of the composition A and the composition B after that, It is possible to more reliably prevent the pattern from being broken due to the blurring at the border between the two.

The average film thickness of the functional film formed as described above is not particularly limited, but is preferably 5 to 50 μm. By repeating the flow of (S4) → (S5) → (S6) shown in FIG. 2, a functional film having a desired film thickness can be formed. When repeating the flow of (S4) → (S5) → (S6), (S4) → (S5) → (S6) → (S5) → (S4) → (S5) → (
Like (S6), you may put the drying process (S5) of a coating film after (S6). The thickness of the functional film can be measured using a known micrometer.

The functional film formed as described above may be a thin film having a predetermined pattern formed by discharging two or more kinds of functional materials to a predetermined region on the substrate by a droplet discharge device. There is no particular limitation. For example, a circuit board is used as a base, and a functional film comprising a conductor layer and an insulating layer having a predetermined pattern on the circuit board, or a positive electrode active material having a predetermined pattern on a current collector as will be described later And a positive electrode layer made of a conductive material.

Even when three or more functional film forming compositions containing functional materials and organic solvents were applied, one functional film forming composition was applied to form a coating film of the composition. later,
Intended by repeating the operation of drying the coating film of the one functional film forming composition, then applying the next functional film forming composition to form the coating film of the composition, and drying A functional layer having a designed pattern can be formed without destroying the pattern.

2) Electrode formation method The electrode formation method of the present invention is an application of the functional film formation method of the present invention to the production of an electrode.
That is, in the electrode forming method of the present invention, two or more types of electrode layer forming materials and a composition for forming an electrode layer containing a solvent are sequentially applied on a current collector by a droplet discharge device, and a predetermined pattern is formed. A method of forming an electrode comprising a step of forming an electrode layer having a step of forming the electrode layer,
After applying one electrode layer forming composition on the current collector to form a coating film of the electrode layer forming material, before applying the next electrode layer forming composition, the one electrode It includes an operation of drying the coating film of the layer forming composition.

In the electrode forming method of the present invention, the two or more electrode layer forming compositions include at least one kind of a positive electrode active material and a first organic solvent, and at least one kind of a carbon-based conductive material, and It is preferable that the composition containing the second organic solvent is used to form the positive electrode of the secondary battery.

The current collector used in the present invention is not particularly limited as long as it is a sheet-like material made of a conductive material. For example, what processed aluminum foil, copper, nickel, stainless steel materials, etc. into metal foil, electrolytic foil, rolled foil, an embossed product, a foam sheet, etc. can be used.
The thickness of the current collector is not particularly limited, but is usually 5 to 30 μm.

The composition for forming two or more electrode layers used in the present invention includes an electrode layer forming composition containing a positive electrode active material and a first organic solvent, and an electrode layer forming containing a conductive material and a second organic solvent. The combination of the composition for use is mentioned.

There is no restriction | limiting in particular as a positive electrode active material, A well-known thing can be used. For example, when forming a positive electrode for a lithium battery, a Li—Mn-based composite oxide such as LiMn ₂ O ₄ , LiCo
Examples thereof include Li—Co based complex oxides such as O ₂ and Li—Ni based complex oxides such as LiNiO ₂ . These positive electrode active materials can be used alone or in combination of two or more.

The conductive material is not particularly limited as long as it is a conductive material, and examples thereof include carbon-based conductive materials such as acetylene black, carbon black, ketjen black, graphite, carbon fiber, and carbon nanotube. These conductive materials can be used alone or in combination of two or more.

Although it does not restrict | limit especially as said 1st and 2nd organic solvent, From a viewpoint of working efficiency, a thing with a boiling point of 50-200 degreeC in a normal pressure is preferable. Examples of the organic solvent include amide solvents such as N-methylpyrrolidone, N, N-dimethylformamide, and N, N-dimethylacetamide; nitrile solvents such as acetonitrile and propionitrile; tetrahydrofuran;
Ether solvents such as 1,2-dimethoxyethane and diisopropyl ether; ketone solvents such as acetone, methyl ethyl ketone, diethyl ketone, methyl isobutyl ketone and cyclohexanone; ester solvents such as ethyl acetate, propyl acetate and methyl lactate; benzene and toluene Aromatic solvents such as xylene and chlorobenzene; halogen solvents such as chloroform and 1,2-dichloroethane; and mixed solvents composed of two or more of these solvents. The first and second organic solvents may be the same or different.

In the present invention, the electrode layer forming composition may further contain other components as desired. Examples of other components include binders such as polyvinylidene fluoride. These other components can be contained in a composition containing a positive electrode active material, or can be contained in a composition containing a conductive material.

The composition containing the positive electrode active material can be prepared by mixing and stirring the positive electrode active material and optionally other components in an organic solvent. The mixing / stirring method is not particularly limited and can be performed using a conventionally known mixing / stirring apparatus.

The mixing ratio of the positive electrode active material, other components, and the organic solvent is not particularly limited. The compounding amount of the positive electrode active material is usually 10% to 60% by weight with respect to the whole composition, and the compounding amount of other components is usually 0% to 20% by weight with respect to the whole composition. The compounding amount of the organic solvent is usually 20% by weight to 90% by weight with respect to the entire composition.

A composition containing a conductive material can be prepared by mixing and stirring the conductive material and, if desired, other components in an organic solvent. The mixing / stirring method is not particularly limited and can be performed using a conventionally known mixing / stirring apparatus.

The blending ratio of the conductive material, other components, and the organic solvent is not particularly limited. The blending amount of the conductive material is usually 10% by weight to 60% by weight with respect to the whole composition, and the blending amount of other components is usually 0% by weight to 20% by weight with respect to the whole composition. The compounding amount of the organic solvent is usually 20% by weight to 90% by weight with respect to the entire composition.

The viscosity of the electrode layer forming composition (a composition containing a positive electrode active material and a composition containing a conductive material) is not particularly limited, but is preferably low enough to enable droplet discharge. The viscosity of the composition is preferably about 1 to 100 cP. Examples of methods for adjusting the viscosity of the composition within this range include a method of changing (increasing) the blending ratio of the organic solvent, a method of increasing the temperature of the composition, a polymer electrolyte raw material that lowers the viscosity, etc. And other methods of adding other compounds to the composition.

Layer configuration example of positive electrode of secondary battery that can be produced by the electrode forming method of the present invention (
FIG. 3 shows a partially enlarged view.
The positive electrode shown in FIG. 3 has a current collector (1) and a positive electrode layer (2) in which a positive electrode active material and a conductive material are formed on the current collector 1 in a predetermined pattern. . In FIG. 3, (a) is a sectional view seen from the side, and (b) is a view seen from above.

In the positive electrode layer 2 shown in FIG. 3, a pattern portion (2b) of a positive electrode active material having a relatively large coating area and a pattern portion of a conductive material having a relatively small coating area on the current collector (1). (2
a) are arranged so that the pattern portion (2a) is positioned at the four apex portions of the square.

The present invention is not limited to the pattern shown in FIG. 3, and the pattern portion (2a) and the pattern portion (
The arrangement of 2b) is arbitrary. For example, as shown in FIG. 4 (a), even if the pattern portion (2a) is arranged so as to be positioned at the four vertex portions and the center portion of the square, as shown in FIG. You may arrange | position so that it may be located in 3 points | pieces (6 points in total).

Next, a method for forming the positive electrode shown in FIG. 3 will be described.
The positive electrode shown in FIG. 3 can be implemented using, for example, the positive electrode production line II within the dotted line in the secondary battery production line I shown in FIG.

The positive electrode production line II has a droplet discharge device 10a (hereinafter referred to as “composition a”) that discharges an electrode layer-forming composition containing a conductive material and a first organic solvent onto a current collector (hereinafter referred to as “composition a”). (Hereinafter referred to as “discharge device 10a”), and a droplet discharge device 10b (hereinafter referred to as “composition b”) that discharges a positive electrode active material and a composition for forming an electrode layer (hereinafter referred to as “composition b”). A discharge device 10b), a vacuum drying device 11, a heat drying device 16a, and a belt conveyor BC1 connecting these devices, including a driving device 13 for driving the belt conveyor BC1 and the like; It is connected to a control device 12 that controls the entire device.

As the discharge devices 10a and 10b, those having the same configuration as that shown in FIG. 1 can be used. In addition, in the positive electrode production line II shown in FIG. 5, the composition a and the composition b
Are performed using separate discharge devices (discharge devices 10a and 10b), but the composition a and the composition b can be discharged by a single discharge device.

First, a current collector such as an aluminum foil having a desired size is prepared. Current collector is belt conveyor BC1
The upper portion is conveyed and taken into the discharge device 10a, and the composition a is applied to a predetermined region on the current collector by the discharge device 10a. The same pattern (same composition) can be overprinted at the same location to form a coating film of the composition a having a desired film thickness.

The current collector on which the coating film of the composition a is formed is taken out from the discharge device 10a and conveyed to the reduced pressure drying device 11, where the coating film of the composition a is dried. The degree of vacuum in the vacuum drying apparatus is a pressure at which the boiling point of the organic solvent contained in the composition a is 20 to 50 ° C. Moreover, drying temperature is 20-100 degreeC normally. In the present embodiment, the coating film of the composition a is dried using a reduced-pressure drying apparatus, but can also be performed using a normal heat drying apparatus.

Next, the current collector on which the dry coating film of the composition a is formed is transported on the belt conveyor BC1 and taken into the discharge device 10b. And the composition b is apply | coated to the predetermined area | region on a collector with the discharge apparatus 10b. Overlay the same pattern (same composition) in the same place,
A coating film of the composition b having a desired film thickness can be formed.

Next, the current collector on which the dry coating film of composition a and the coating film of composition b were formed was discharged from the discharge device 10
b, taken on the belt conveyor BC1, and taken into the heating and drying device 16a. And the coating film of the composition a and the composition b is heat-dried with the heat drying apparatus 16a, and the positive electrode layer which has the layer structure shown in FIG. 3 is formed.
The heating temperature in the heating / drying device 16a may be a temperature at which the solvent contained in the compositions a and b can be completely removed by drying. Usually, it is 50-200 degreeC.

The average film thickness of the positive electrode layer formed as described above is not particularly limited, but is 5 to 50.
It is preferably μm. Moreover, the average thickness of the electrode in which the electrode layer is formed on one side of the current collector is 1
It is preferably 0 to 70 μm. In addition, the thickness of an electrode and a battery can be measured using a well-known micrometer.

Further, the area of the electrode surface is not particularly limited, but in general, the larger the area of the electrode surface,
It becomes difficult to maintain the uniformity of the electrode surface. From this viewpoint, the present invention is particularly beneficial when the area of the electrode surface is 50 cm ² or more.

In the positive electrode layer obtained as described above, the composition a contains a conductive material, and the composition b contains a positive electrode active material. When the positive electrode layer is formed in a desired pattern, a part of the fine particles of the positive electrode active material comes into contact with the fine particles of the conductive material that is electrically connected to the current collector. That is, since a part of the positive electrode active material is disposed so as to be in close contact with the conductive material, a conductive path can be secured, the internal resistance can be lowered, and good electron conductivity can be secured. According to the present invention, since the intended pattern is not broken, the required energy can be easily taken out (high output) even when charging / discharging with a large current as designed.

In the case of applying a positive electrode layer forming composition containing three or more kinds of electrode layer forming materials and an organic solvent, a single positive electrode layer forming composition is applied and the coating film of the composition is applied. After forming the coating film, the coating film of the one positive electrode layer forming composition is dried, and then the next positive electrode layer forming composition is applied to form a coating film of the composition. Thus, a positive electrode layer having a designed pattern can be formed without destroying the intended pattern.

3) Method for producing secondary battery The method for producing a secondary battery according to the present invention comprises a negative electrode, an electrolyte, a current collector, and two or more positive electrode forming materials formed on the current collector. It is a manufacturing method of the secondary battery which has a positive electrode which consists of a positive electrode layer to contain, Comprising: The said positive electrode is formed with the formation method of the electrode of this invention mentioned above.

In the method for producing a secondary battery of the present invention, since the positive electrode is formed by the method for forming an electrode of the present invention, a secondary battery having charge / discharge characteristics intended by the electrode can be obtained.

In the secondary battery, a positive electrode, an electrolyte, and a negative electrode are arranged in this order, and these are sealed in an exterior material. Specifically, a secondary battery can be assembled by producing a positive electrode and a negative electrode, respectively, interposing an electrolyte in the obtained positive electrode and negative electrode, and sealing them in an exterior material.

Specifically, the method for manufacturing a secondary battery of the present invention can be carried out by a secondary battery manufacturing line I shown in FIG.
In the production line I, the positive electrode is produced by the electrode production line II shown in the dotted line, and in parallel therewith, the discharge device 10c, the heating and drying device 16b, the belt conveyor BC.
The negative electrode is formed in the same manner as the method for forming the positive electrode by the production line for forming the negative electrode composed of 2, and the obtained positive electrode and the negative electrode are accommodated in the exterior material in the assembly device 15, A secondary battery can be manufactured by supplying and enclosing an electrolyte from the electrolyte supply device 14.

An example of a lithium battery obtained by the production method of the present invention is shown in FIG. Battery 2 shown in FIG.
Reference numeral 0 denotes a stacked lithium battery in which the positive electrode 30 and the negative electrode 40 are separated by a separator 50.

In FIG. 6, the positive electrode 30 has a structure in which a current collector 30a and a positive electrode layer 30b are stacked in series, and the negative electrode 40 has a structure in which a current collector 40a and a negative electrode layer 40b are stacked in series. Have The positive electrode and the negative electrode are filled with an electrolyte (not shown).

Examples of the electrolyte include LiCIO ₄ , LiPF ₆ , LiBF ₄ , LiAsF ₆ , L
iSbF ₆ , LiCF ₃ SO ₃ , LiC ₄ F ₉ SO ₃ , LiCF ₃ CO ₂ , Li ₂ C ₂ F
₄ (SO ₃ ) ₂ , LiN (CF ₃ SO ₂ ) ₂ , LiC _n F _{2n + 1} SO ₃ (n ≧ 2), L
iN (RfOSO ₂ ) ₂ (where Rf represents a fluoroalkyl group), LiN (CF ₃
SO ₂ ) (C ₄ F ₉ SO ₂ ), LiN (C ₂ F ₅ SO ₂ ) (C ₄ F ₉ SO ₂ ), LiN (
CF ₃ SO ₂ ) (C ₂ F ₅ SO ₂ ); macromers of ethylene oxide and propylene oxide; gel polymer electrolytes composed of various polymers, intrinsic polymer electrolytes, inorganic solid electrolytes such as LiPON; Li ion-containing room temperature dissolved salts; Can be mentioned.

When the electrolyte contains a solvent, examples of the solvent include 1,2-dimethoxyethane, 1,2-diethoxyethane, propylene carbonate, ethylene carbonate, ν-butyrolactone, tetrahydrofuran, 1,3-dioxolane, diethyl carbonate. , Dimethyl carbonate, ethyl methical carbonate and the like. These can be used singly or in combination.

The separator is not particularly limited as long as it can withstand the usage range of the secondary battery.
Examples thereof include those formed by combining single or composite microporous films such as olefinic resins such as polyethylene and polypropylene; copolymers of polypropylene and polyethylene and the like.
Although the thickness of a separator is not specifically limited, Usually, it is 10-50 micrometers.

The exterior material is not particularly limited, and examples thereof include a polymer metal composite film in which at least a metal foil film and a resin film are laminated.

In an industrial production process of a secondary battery, in order to improve productivity, a process of producing an electrode larger than the final battery size and cutting it into a predetermined size may be employed. .

Examples of the shape of the secondary battery include a laminate type, a cylindrical type, and a flat plate type.
For example, a laminate-type secondary battery is prepared by cutting out the positive electrode and the negative electrode manufactured as described above into appropriate sizes, attaching terminals, and holding an electrolyte membrane between the two in a dry argon atmosphere. Can be manufactured by vacuum-sealing in an aluminum laminate pack in a state of being pulled out.

For example, a cylindrical secondary battery uses the positive electrode and the negative electrode manufactured as described above, and is laminated and wound in the order of the positive electrode, the separator, the negative electrode, and the separator, and cut into a predetermined length. And it can manufacture by inserting in an iron cylinder can, adding electrolyte, and sealing.

In the lithium battery 20 shown in FIG. 6, for example, LiCoO ₂ is used as the positive electrode active material and carbon (C) is used as the negative electrode active material, and charging / discharging can be repeated as shown below.

(In the formula, x is a positive number less than 1.)
The battery manufactured according to the present invention is particularly useful when used for vehicles that require high output and high energy density and require very severe conditions. The obtained battery has high durability against vibration, and even when used in an environment in which vibration is constantly applied, such as an automobile, the battery is hardly deteriorated due to resonance.

It is a figure which shows the outline of an example of the droplet discharge apparatus used for this invention. It is a flowchart which shows the procedure of the formation method of the functional film of this invention. It is the figure which represented typically the example of a pattern of the positive electrode layer manufactured by this invention. It is the figure which represented typically the example of a pattern of the positive electrode layer manufactured by this invention. It is the figure which represented typically an example of the manufacturing line used for manufacture of the secondary battery of this invention. It is the figure which represented typically an example of the lithium battery obtained by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Current collector, 2 ... Positive electrode layer, 2a ... Conductive material, 2b ... Positive electrode active material 10, 10a, 1
0b, 10c ... droplet discharge device, 11 ... heating and drying device, 12 ... control device, 13 ... drive device,
DESCRIPTION OF SYMBOLS 14 ... Electrolyte supply apparatus, 15 ... Assembly apparatus, 16a, 16b ... Heat drying apparatus, 20 ... Lithium secondary battery, 30 ... Positive electrode layer, 30a, 40a ... Current collector, 30b ... Positive electrode layer, 40b ... Negative electrode layer 50 ... Separator 100 ... Computer 101 ... Drawing unit 102 ... Input terminal 103 ... Storage device 104 ... Display 105 ... Container 106 ... Discharge nozzle
107 ... Substrate, 108 ... Functional membrane

Claims (6)

A functional film forming method for forming a functional film having a predetermined pattern by sequentially applying a functional film forming composition containing two or more functional materials and an organic solvent on a substrate by a droplet discharge device Because
After coating one functional film forming composition on the substrate to form a coating film of the composition, before applying the next functional film forming composition, the one functional film forming composition A method for forming a functional film, comprising a step of drying a coating film of a product. A functional film having a predetermined pattern on the same plane is formed by sequentially applying a composition for forming a functional film containing two or more functional materials and an organic solvent on the same plane of the substrate by a droplet discharge device. A method of forming a functional film to be formed,
After applying one functional film forming composition on the same plane of the substrate to form a coating film of the composition, before applying the next functional film forming composition, the one functional film A method for forming a functional film, comprising a step of drying a coating film of the forming composition. A step of forming an electrode layer having a predetermined pattern by sequentially applying a composition for forming an electrode layer containing two or more electrode layer forming materials and an organic solvent on a current collector by a droplet discharge device. A method of forming an electrode comprising:
In the step of forming the electrode layer, after applying one electrode layer forming composition on the current collector to form a coating film of the electrode layer forming composition, the next electrode layer forming composition A method of forming an electrode comprising an operation of drying a coating film of the composition for forming an electrode layer before applying an object. On the same plane of the current collector, two or more kinds of electrode layer forming materials and an electrode layer forming composition containing an organic solvent are sequentially applied by a droplet discharge device to have a predetermined pattern on the same plane. A method of forming an electrode comprising a step of forming an electrode layer,
In the step of forming the electrode layer, after coating one electrode layer forming composition on the same plane of the current collector to form a coating film of the electrode layer forming composition, the next electrode layer A method of forming an electrode comprising the step of drying the coating film of the one electrode layer forming composition before applying the forming composition. As the two or more kinds of electrode layer forming compositions, a composition containing at least one kind of positive electrode active material and a first organic solvent, and a composition containing at least one kind of conductive material and a second organic solvent are used. The method for forming an electrode according to claim 3, wherein the positive electrode of a secondary battery is formed. A method for producing a secondary battery having a positive electrode comprising a negative electrode, an electrolyte, and a current collector, and a positive electrode layer formed on the current collector and containing two or more positive electrode forming materials. And
The method for producing a secondary battery, wherein the positive electrode is formed by the electrode forming method according to claim 5.

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