JP3460315B2 - Method for producing electrode plate and chemical battery - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an electrode plate of a chemical battery.

[0002]

2. Description of the Related Art In order to improve the productivity of electrode plates of chemical cells, there is a manufacturing method in which an uncoated portion is provided on a conductive support at right angles to the running direction by using, for example, a doctor blade. 184069 and Japanese Unexamined Patent Publication No. 1-1942.
65 publication. However, in the above-mentioned publication, in the case of a doctor system provided with a shutter member, the liquid reservoir is opened and closed by separating and abutting the shutter member to supply and drain the coating liquid to the conductive support. Since there is a gap between the shutter part and the running conductive support,
Even if the shutter portion is separated, the coating is not started until the electrode material coating liquid reaches the conductive support. Immediately after the start, since the sufficient amount of the coating liquid is not supplied to the gap, the thickness of the applied electrode material gradually increases. Further, even if the shutter portion is brought into contact with the doctor, since the coating liquid remains in the gap, the coating is continued, and since the coating liquid is not supplied, the thickness of the electrode material to be coated gradually decreases. However, the liquid does not run out evenly in the width direction. Since the application thickness is reduced by applying and draining, the amount of active material in the application part used as an electrode is reduced and the discharge capacity is reduced. Further, when the viscosity of the coating liquid changes, the time required for the coating liquid to reach the conductive support after the shutter member is separated changes, and the uncoated portion having a certain width is not formed. Further, when a foreign material is caught on the shutter member sliding portion, the shutter member cannot be completely brought into contact with the doctor, and there is a problem that an uncoated portion cannot be formed.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method of manufacturing an electrode in a chemical battery, which can reduce the manufacturing fluctuation of the discharge capacity and improve the efficiency of the process.

[0004]

SUMMARY OF THE INVENTION The above-mentioned problems are solved in a method of forming an uncoated portion in a direction perpendicular to the running direction of a conductive support, and the viscosity of the electrode material coating liquid is 0.5 Pas to 300 Ps.
The supply of the electrode material coating liquid to the extrusion type liquid injector having the as and the slot nozzle is repeatedly supplied and stopped, and / or the distance between the tip of the slot nozzle and the traveling conductive support is changed. This is achieved by a method for manufacturing an electrode for a chemical battery, which is characterized by the following.

In the extrusion type liquid injector 21 used in the present invention, as shown in FIG. 1, a slot 18 is formed so that two lips 16 and 17 face each other so as to maintain a gap, and a liquid reservoir connected to this slot. 20 inside. The electrode material coating liquid is quantitatively supplied to this liquid reservoir by a liquid supply facility provided outside the liquid injector, and further discharged from a slot nozzle through a connected slot. The slot nozzle tip is installed so as to keep a distance from the running conductive support 14, and the electrode material coating solution discharged from the slot nozzle is applied in layers on the conductive support. When the supply of the electrode material coating liquid discharged from the slot nozzle through the slot is stopped, the supply of the electrode material coating liquid on the conductive support is stopped simultaneously and uniformly in the width direction of the extrusion type liquid injector. . When the supply of the electrode material coating liquid to the slot is restarted, the supply of the electrode material coating liquid to the conductive support is restarted at the same time, and the liquid is evenly ejected in the width direction. While the coating liquid is not supplied to the slots, an uncoated portion where the electrode material coating liquid does not exist is formed on the running conductive support. In other words, if the supply and stop of the electrode material coating solution are carried out intermittently, the uncoated part will be formed at right angles to the running direction of the conductive support according to the length of time during which the coating solution is not supplied. By appropriately setting the gap, it is possible to form a coated portion and a non-coated portion having a desired width on the conductive support. Supply and stop of the electrode material coating liquid to the slot may be performed by operating and stopping the liquid supply equipment, or operating a flow path changing device such as a valve provided between the extrusion type liquid injector and the liquid supply equipment. . In addition, a device for intermittently interrupting the supply of the coating liquid to the slot may be provided in the extrusion type liquid injector.

When the distance between the tip of the slot nozzle and the running conductive support is expanded while the fixed amount of the electrode material coating solution is supplied to the slot, the electrode material coating solution discharged from the slot nozzle reaches the conductive support. The coating solution does not exist at all, and an uncoated portion where the coating liquid does not exist is formed on the conductive support. When the distance between the tip of the slot nozzle and the conductive support is narrowed, the electrode material coating liquid again reaches the conductive support and starts forming a coating layer. Since the amount of the electrode material coating liquid discharged from the slot nozzle is adjusted to be uniform in the width direction of the extrusion type liquid injector, the coating and the liquid draining are simultaneously performed in the width direction. Therefore, an uncoated portion having a width corresponding to the time during which the gap between the tip of the slot nozzle and the conductive support is expanded is formed at right angles to the running direction of the conductive support. The distance between the tip of the slot nozzle and the conductive support may be changed by moving the liquid injector having the slot nozzle or moving the conductive support.
When the support rolls around the backup roll as shown in FIG. 1 to travel, the backup roll can be moved. As a method of moving the liquid injector and backup roll,
A hydraulic cylinder, a pneumatic cylinder, an electric slider having a ball screw feeding mechanism, etc. can be used,
It is not limited to this. The method of controlling the distance between the tip of the slot nozzle and the conductive support is not particularly limited, and examples thereof include a cylinder stroke adjustment method and a stopper method. It is also possible to combine the change of the distance between the tip of the slot nozzle and the conductive support and the supply and stop of the supply of the electrode material coating solution to the slot. The width of the uncoated portion formed on the conductive support according to the present invention is determined by the size of the welded portion and the like and is not particularly limited, but is preferably 0.3 cm to 5 cm. In the coating method, the viscosity of the electrode material coating liquid is 0.5 at 25 ° C. as measured by a B-type viscometer (manufactured by Tokimec Co., Ltd.).
The range of Pas to 300 Pas is good, and preferably 0.6.
Pas to 100 Pas, more preferably 0.7 Pa
s to 50 Pas is preferable. Further, the transport speed of the conductive support in the present invention is not particularly limited, but it may be 0.
1 to 100 m / min is preferable, and 0.1 to 50 m / min is particularly preferable. In the case of sequentially applying both surfaces, the application of the second surface (back surface) opposite to the first surface (front surface) and the position of the end of application are aligned. When applying the second surface, apply the first surface, detect the position of the end of application and apply the second surface,
Although the coating finishes are synchronized, the detection method is preferably an optical method or a physical method of coating the first surface by displacement of a roll or the like, or detecting the coating finish. Furthermore, by placing the extrusion type liquid injector on both sides of the conductive support, the coating can be performed on both sides of the conductive support. In this case, simultaneous coating or sequential coating may be used. The conductive support in the present invention is not particularly limited, but a metal foil (aluminum, copper, nickel, stainless steel, etc.), an inorganic oxide, an organic polymer material, or a conductive film such as carbon is used. You can
The conductive support may be in the form of a continuous body, a hole or a net, but a continuous body is particularly preferable. The thickness of the conductive support is
1 to 200 μm is preferable.

Electrode material coating liquid applied according to the present invention
Contains an electrode active material, conductive agent, binder, solvent, etc.
Can be done. As the electrode active material, H⁺, Li⁺, N
a⁺, K ⁺Is a compound that can be inserted and / or released
However, especially transition metal oxides and transition metal
Cogenide, carbonaceous materials, Periodic Table IVB, VB group semimetals
It is possible to use an oxide mainly composed of
Transition metal oxide, transition metal oxide, carbonaceous material,
Oxides mainly composed of Group IVB and VB semimetals of the Periodic Table are preferred.
Good (Transition metals are mainly Mn, Co, Ni, V, Fe
It is preferable that IVB and VB groups of the periodic table are Ge,
It is preferable to mainly use Sn, Pb, Bi, and Si.
Yes. ) Specifically, LiCoO₂, LiNiO₂, LiC
o_0.5Ni_0.5O₂, LiMn₂O_Four, LiCoV
O_Four, LiNiVO_Four, LiCo_0.9Sn_{0. 1}O₂, L
iCo_0.9Ti_0.1O₂, LiCo_0.9Al_0.1O₂,
LiCo_0.9In_0.1O₂, LiCo_0.9Y_0.1O₂,
LiCo_0.9Ce_0.1O₂, Fe₃O _Four, V₆O₁₃, V
₂O_Five, And so on. As a preferred carbonaceous material
Has a 002 surface spacing of 3.35 to 3.80 A (ong.
), Density of 1.1-1.7g / cm³Things
Preferably, graphite, petroleum coke, cresol resin fired carbon
Elemental, furan resin firing carbon, polyacrylonitrile fiber firing
Carbon, vapor grown carbon, mesophase pitch calcined carbon, etc.
Can you name some? Periodic table IVB, VB group semi-metal
As the oxide mainly composed of GeO, GeO₂, Sn
O, SnO₂, PbO, PbO₂, Pb₂O₃, Pb₃
O_Four, Sb₂O₃, Sb₂O_Four, Sb₂O _Five, Bi₂O
₃, Bi₂O_Four, Bi₂O_Five, SiSnO₃, Li₂S
iO₃, Li_FourSiO_Four, Li₂Si₃O₇, Li₂S
i₂O_Five, Li₈SiO₆, Li₆Si₂O₇, Li_Four
Ge₉O₂₀, Li₆Ge₈O₁₉, Li_FourGe_FiveO₁₂, L
i₆Ge₂O₇, Α-Li_FourGeO_Four, Li_FourGe
O_Four, Β-Li₈GeO₆, Li ₂Ge₇O₁₅, Li₂
GeO₃, Li₂Ge_FourO₉, Li₂SnO₃, Li₈
SnO₆, Li₂PbO₃, Β-Li₂PbO₃, Li
₈PbO₆, Li_FourPbO _Four, Li₇SbO₆, LiS
bO₃, Li₃SbO_Four, Li₃BiO_Four, Li₇Bi
O₆, Li_FiveBiO_Five, LiBiO₂, Li_FourBi₆O
₁₁, Li_FourMgSn ₂O₇, Li₂MgSn₂O₆, L
i₂MgSn₃O₆, Li₂Mg₃SnO₆, Li_FourM
g₂SnO₆But not limited to
It is not done.

The conductive agent may be any electron conductive material that does not undergo a chemical change in the constructed battery.
Usually, one or a mixture of conductive materials such as natural graphite (scaly graphite, flake graphite, etc.), artificial graphite, carbon black, acetylene black, Ketjen black, carbon fiber, metal powder, metal fiber or polyphenylene derivative. Can be included as The combined use of graphite and acetylene black is particularly preferred. As the binder, at least one kind of a polymer having a polysaccharide, a thermoplastic resin and a rubber elasticity, or a mixture thereof can be used. Preferred examples are starch, polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, regenerated cellulose, diacetyl cellulose, polyvinyl chloride, polyvinylpyrrolidone, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, ethylene-propylene-diene terpolymer. (EPDM), sulfonated EPDM, styrene butadiene rubber, polybutadiene, fluororubber and polyethylene oxide. The binder may be dissolved in a solvent or may be precipitated such as dispersed or suspended. As the solvent, water or at least one organic solvent or a mixture thereof can be used. The solvent is not particularly limited, N-methylpyrrolidone, xylene, toluene, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, ethanol, methanol, methyl acetate, ethyl acetate, butyl acetate, methylene chloride, ethylene chloride, etc. preferable. In the present invention, the composition of the electrode material coating liquid is not particularly limited, but the coating liquid is usually the electrode active material 100.
1 to 50 parts by weight of the conductive agent and 0.1 to 0.1 parts by weight of the binder.
It comprises 50 parts by weight and 30 to 600 parts by weight of solvent.

As the shape of the chemical battery, coins, buttons,
It can be used for both cylindrical and square types. Positive according to the invention
When manufacturing batteries using sheet electrodes of the negative and positive electrodes
When separating the positive electrode sheet and the negative electrode sheet,
For example, polyethylene, microporous polypropylene fiber
Polypropylene such as film separator, glass fiber
Etc. As the electrolyte, for example, an organic solvent
As propylene carbonate, ethylene carbonate
G, butylene carbonate, dimethyl carbonate, di
Ethyl carbonate, γ-butyrolactone, 1,2-di
At least aprotic organic solvents such as methoxyethane
Also a solvent mixed with one or more kinds, and Lithium that dissolves in that solvent
Salt, eg LiClO_Four, LiBF_Four, LiPF₆,
LiCF₃SO ₃, LiCF₃CO₂, LiAsF₆Na
A solution consisting of any one or more salts
It Among them, propylene carbonate or ethylene
Carbonate or ethylene carbonate and 1,2-
Dimethoxyethane and / or diethyl carbonate
LiCF in the mixed solution of₃SO₃, LiClO_Four, LiBF
_FourAnd / or LiPF₆An electrolyte containing is preferred.
In particular, at least ethylene carbonate and LiPF₆To
It is preferable to include. The shim produced by the method of the present invention.
The electrode plate can be used for primary and secondary batteries.
Wear. That is, the present invention is also applied to primary batteries
Is.

Mixing used to prepare the coating solution,
As the dispersing device, a horizontal cylindrical mixer, a V mixer, a double cone mixer, a paddle mixer, a ribbon mixer, a planetary motion mixer, a screw mixer, a high speed fluid mixer,
A horizontal single-screw kneader, a horizontal double-screw kneader, a vertical-screw kneader, etc. are preferable. Specifically, vertical ribbon mixer, horizontal ribbon mixer, vertical screw mixer, horizontal screw mixer, ball mill, pin mixer, double-arm kneader, pressure kneader, sand grinder, universal mixer, ladle mixer, cutter. Examples thereof include mixers, but are not limited thereto. Of course, the mixing and dispersing device may be combined and used. The conductive support coated with the electrode material is transported to the drying chamber to remove the solvent.
The drying method is not particularly limited, and a general method can be used, and hot air drying, infrared ray, contact drum method and the like are preferable. In the case of hot air drying, the drying temperature is 3
0-250 degreeC is good and 40-200 degreeC is especially preferable.
The electrode material is sequentially or simultaneously applied to the front and back surfaces of the conductive support, dried and then pressed. The diameter of the press roller is preferably 300 mm or more and 3000 mm or less, and the pressing pressure is 2000 Kg / cm ² or more and 10000.
Kg / cm ² is preferred. When the solvent cannot be removed sufficiently by the drying, a drying step can be further provided after the pressing. As a drying method, vacuum drying, infrared ray, high temperature drying, or a combination thereof can be used.

[0011]

The present invention will be described in more detail with reference to the following examples, but the invention is not limited to the following examples as long as the gist of the present invention is not exceeded. Example 1 87 parts by weight of LiCoO ₂ as a positive electrode active material and 9 parts by weight of graphite as a conductive agent were mixed, and further 3 parts by weight of polytetrafluoroethylene and 1 part by weight of sodium polyacrylate were added as a binder, Water was added as a solvent, and the mixture was kneaded and dispersed using a universal mixer having a rotating stirring blade and a stirring blade that rotates while revolving, to prepare a slurry of a positive electrode material coating liquid. As shown in FIG. 2, the coating machine is composed of feeding, coating section, drying chamber, and winding. To perform double-sided coating, one side (front surface) of the conductive support is coated, dried and rolled up. After that, reattach to the delivery and apply the opposite side (back side). An aluminum foil having a thickness of 30 μm was used as a conductive support, a coating device as shown in FIG. 3 was used, and coating was performed on each side using a three-way valve as a flow path changing device. When applying the back surface, the application start position on the front surface side was detected, and the three-way valve was opened / closed in synchronization with this to match the positions of the unapplied parts on both sides. The distance between the slot nozzle and the conductive support is 0.5
mm, the slot clearance was 0.5 mm, the width of the lip surfaces on the inlet side and the outlet side was 2 mm, and the coating speed was 1 m / min. The liquid supply to the extrusion type liquid injector of the three-way valve was stopped, that is, the valve was closed for 1.8 seconds to form an uncoated portion having a width of 3 cm. The solid content of the electrode material coating liquid is 60% by weight, and the apparent viscosity is 1 Pa.
It was s. Drying room consists of 4 rooms, and each room is slit type hot air drying with an opening ratio of 8%.
The temperature was 40 ° C., the slit air velocity was 3 m / sec, the third chamber and the fourth chamber were dried at a temperature of 50 ° C. and the slit air velocity was 6 m / sec. The dry air supplied to each room was controlled to have a dew point of 9 ° C. After performing double-sided coating, compression molding was performed by a roller press machine to prepare a positive electrode sheet having a thickness of 370 μm.
The roller press has a roller diameter of 500 mm, a roller hardness (Shore D hardness) of 90 degrees, and a pressure of 4000 Kg / cm.
^{I went with 2} times 3 times.

LiCoVO ₄ (lithium carbonate, cobalt oxide, and vanadium pentoxide was used as a negative electrode active material in the air
86 parts by weight) (calcined at 000 ° C. for 24 hours), 3 parts by weight of acetylene black and 6 parts by weight of graphite as a conductive agent, and 4 parts by weight of styrene-butadiene rubber and 1 part by weight of carboxymethylcellulose as a binder are added. Then, a negative electrode material coating solution was prepared by kneading and dispersing using a universal mixer having water added as a solvent and rotating agitating blades and agitating blades rotating and revolving. Both sides of a copper foil having a thickness of 20 μm were applied one by one in the same manner as the positive electrode. The distance between the slot nozzle and the conductive support is 0.3 mm, the slot clearance is 0.5 mm, the width of the inlet and outlet lip surfaces is 3 mm, and the transport speed is 2 m / m.
I went in. Similarly to the positive electrode, the three-way valve was used to supply and stop the supply of the electrode material coating liquid to the extrusion liquid injector. The valve was closed for 1.5 seconds to form an uncoated portion having a width of 5 cm. The solid content of the electrode material coating liquid was 50% by weight, and the apparent viscosity was 5 Pas. Drying is done in the first and second chambers at 50 ° C, slit air velocity 3m / se
c, 3rd chamber, 4 chambers 60 ° C, slit wind speed 10m / se
The dry air supplied to each room under the condition of c) has a dew point of 8
Controlled to ° C. After performing double-sided coating, compression molding was performed by a roller press machine to form a negative electrode sheet having a thickness of 220 μm. The roller press had a roller diameter of 500 mm, a roller hardness (Shore D hardness) of 90 degrees, and a pressure of 6000 Kg.
/ Cm ² was applied twice.

Example 2 The positive electrode material coating solution and the negative electrode material coating solution of Example 1 were applied using an extrusion type liquid injector. The positive electrode material coating solution was applied to both sides of an aluminum foil having a thickness of 30 μm, one side at a time. The gap between the slot nozzle and the conductive support during coating is 0.5 mm, the slot clearance is 0.5 mm, the widths of the inlet and outlet lip surfaces are 2 mm,
The transportation speed was 1 m / min. The gap between the tip of the slot nozzle and the conductive support was intermittently kept at 5 mm for 1.8 seconds to form an uncoated portion having a width of 3 cm. Drying and roller pressing were performed under the same conditions as the positive electrode of Example 1, and the thickness was 370.
A positive electrode sheet of μm was prepared. The negative electrode material coating solution was applied to both surfaces of a copper foil having a thickness of 20 μm, one surface at a time. The distance between the tip of the slot nozzle and the conductive support was 0.3 mm, the slot clearance was 0.5 mm, the width of the inlet and outlet lip surfaces was 3 mm, and the transport speed was 2 m / min. The interval between the tip of the slot nozzle and the conductive support is intermittently set to 1.
It was kept at 5 mm for 5 seconds to form an uncoated portion having a width of 5 cm.
Drying and roller pressing were performed under the same conditions as the negative electrode of Example 1 to prepare a negative electrode sheet having a thickness of 220 μm.

Example 3 A positive electrode sheet was prepared in the same manner as in Example 1. 86 parts by weight of SnO as a negative electrode active material, 3 parts by weight of acetylene black as a conductive agent and 6 parts by weight of graphite were mixed, and further 4 parts by weight of polyvinylidene fluoride and 1 part by weight of carboxymethyl cellulose were added as a binder.
Water was added as a solvent and kneaded and dispersed using the same disperser as in Example 1 to prepare a negative electrode material coating solution. 20μ
The copper foil of m was coated on both sides in the same manner as in Example 1.
The distance between the tip of the slot nozzle and the conductive support is 0.2 m
m, the slot clearance was 0.5 mm, the width of the inlet-side and outlet-side lip surfaces was 3 mm, and the conveying speed was 2 m / min. Similarly to the positive electrode, the three-way valve was used to supply and stop the supply of the electrode material coating liquid to the extrusion liquid injector. The valve was closed for 1.5 seconds to form an uncoated portion having a width of 5 cm. The solid content of the electrode material coating liquid was 50% by weight, and the apparent viscosity was 3 Pas. Drying is first
Chamber and second chamber, 60 ° C, slit wind speed 5m / sec, third
The chambers and 4 chambers were operated under the conditions of 80 ° C. and a slit wind speed of 10 m / sec, and the dry air supplied to each room was controlled to have a dew point of 8 ° C. After coating on both sides, compression molding was carried out by a roller press machine to prepare a negative electrode sheet having a thickness of 100 μm. The roller press had a roller diameter of 500 mm, a roller hardness (Shore D hardness) of 90 degrees, and a pressure of 4000 Kg / cm ^2.
I went on twice.

Example 4 A positive electrode sheet was prepared in the same manner as in Example 1. Example 3
A negative electrode sheet was prepared by using the negative electrode material coating liquid of.
The negative electrode material coating solution is applied to both sides of a copper foil having a thickness of 20 μm, one surface at a time, the distance between the tip of the slot nozzle and the conductive support is 0.2 mm, and the slot clearance is 0.5 mm.
The width of the inlet and outlet lip surfaces is 3 mm, and the transfer speed is 2 m.
/ Min. The gap between the tip of the slot nozzle and the conductive support was intermittently kept at 5 mm for 5 seconds to form an uncoated portion having a width of 5 cm. Drying and roller pressing were performed under the same conditions as for the negative electrode of Example 3 to prepare a negative electrode sheet having a thickness of 100 μm.

Example 5 A positive electrode sheet was prepared in the same manner as in Example 1. 86 parts by weight of SiSnO ₃ as a negative electrode active material, ₃ parts by weight of acetylene black as a conductive agent and 6 parts by weight of graphite were mixed, and further 4 parts by weight of polyvinylidene fluoride as a binder and 1 part by weight of carboxymethyl cellulose were added,
Water was added as a solvent and kneaded and dispersed using the same disperser as in Example 1 to prepare a negative electrode material coating solution. The solid content of the electrode material coating liquid was 50% by weight, and the apparent viscosity was 2.5 Pas. Application, drying and roller pressing were performed in the same manner as in Example 3 to prepare a negative electrode sheet having an uncoated portion width of 5 cm and a thickness of 100 μm.

Example 6 A positive electrode sheet was prepared in the same manner as in Example 1. Example 5
Using the negative electrode material material coating liquid of No. 4, coating, drying and roller pressing were performed under the same conditions as those of the negative electrode of Example 4 to prepare a negative electrode sheet having an uncoated portion width of 5 cm and a thickness of 100 μm. Example 7 0.5 P by changing the amount of water added to the positive electrode material of Example 1.
An electrode material coating solution of as was prepared, and coating, drying and roller pressing were performed in the same manner as in the positive electrode of Example 1, and the uncoated portion width was 3c.
A positive electrode sheet having a thickness of m and a thickness of 370 μm was prepared. The negative electrode sheet was prepared in the same manner as in Example 1.

Example 8 The amount of water added to the positive electrode material of Example 1 was changed to 0.5 P.
An electrode material coating solution of as was prepared, and coating, drying and roller pressing were performed in the same manner as the positive electrode of Example 2, and the uncoated portion width 3c.
A positive electrode sheet having a thickness of m and a thickness of 370 μm was prepared. The negative electrode sheet was prepared in the same manner as in Example 2. Example 9 300P by changing the amount of water added to the positive electrode material of Example 1
An electrode material coating solution of as was prepared, and coating, drying and roller pressing were performed in the same manner as in the positive electrode of Example 1, and the uncoated portion width was 3c.
A positive electrode sheet having a thickness of m and a thickness of 370 μm was prepared. The negative electrode sheet was prepared in the same manner as in Example 1. Example 10 300P by changing the amount of water added to the positive electrode material of Example 1
An electrode material coating solution of as was prepared, and coating, drying and roller pressing were performed in the same manner as the positive electrode of Example 2, and the uncoated portion width 3c.
A positive electrode sheet having a thickness of m and a thickness of 370 μm was prepared. The negative electrode sheet was prepared in the same manner as in Example 2.

Comparative Example 1 The positive electrode material coating solution and the negative electrode material coating solution of Example 1 were applied using a gravure coating method. The positive electrode material coating solution was applied to both sides of an aluminum foil having a thickness of 30 μm, one side at a time. The boundary layer between cells is 3 cm
Using a roller of 3 cm, the uncoated part with a width of 3 cm has a transport speed of 1 m.
/ Min. Negative electrode material coating liquid has a thickness of 20
On both sides of the copper foil of μm, using a roller of the boundary layer of the cell portion of 5 cm on each side, coating is performed at 2 m / min and 5c.
m uncoated part was formed. The positive electrode and negative electrode coatings were respectively treated under the drying and roller pressing conditions of Example 1,
A positive electrode sheet having a thickness of 370 μm and a negative electrode sheet having a thickness of 220 μm were prepared. Comparative Example 2 The positive electrode material coating solution and the negative electrode material coating solution of Example 1 were applied using a doctor system as shown in FIG. 4, and the supply of the electrode material coating solution to the doctor blade and the stop of the supply were performed by the shutter section. Was opened and closed with an air cylinder. The positive electrode material coating solution was applied to both sides of an aluminum foil having a thickness of 30 μm, one side at a time. Transport speed is 1
The shutter portion was intermittently closed for 1.8 seconds at m / min to form a non-coated portion having a width of 3 cm. The negative electrode material coating solution was applied to both sides of a copper foil having a thickness of 20 μm, one surface at a time. The conveyance speed was 2 m / min, and the shutter portion was intermittently closed for 1.5 seconds to form an uncoated portion having a width of 5 cm. The positive electrode and negative electrode coating materials were treated under the drying and roller pressing conditions of Example 1 to prepare a positive electrode sheet having a thickness of 370 μm and a negative electrode sheet having a thickness of 220 μm.

Comparative Example 3 A positive electrode sheet was prepared in the same manner as in Comparative Example 1. The negative electrode material coating liquid of Example 3 was applied in the same manner as in Comparative Example 1 to form an uncoated portion having a width of 5 cm, and the same drying as in Example 3 was performed.
A negative electrode sheet having a thickness of 100 μm was prepared under the roller press conditions. Comparative Example 4 A positive electrode sheet was prepared in the same manner as in Comparative Example 2. The negative electrode material coating solution of Example 3 was applied in the same manner as in Comparative Example 2 to form an uncoated portion having a width of 5 cm, and the same drying and roller pressing conditions as in Example 3 were used, and a negative electrode sheet having a thickness of 100 μm was formed. It was created. Comparative Example 5 A positive electrode sheet was prepared in the same manner as in Comparative Example 1. The negative electrode material coating solution of Example 5 was applied in the same manner as in Comparative Example 1 to form an uncoated portion having a width of 5 cm, and the same drying as in Example 3 was performed.
A negative electrode sheet having a thickness of 100 μm was prepared under the roller press conditions. Comparative Example 6 A positive electrode sheet was prepared in the same manner as in Comparative Example 2. The negative electrode material coating liquid of Example 5 was applied in the same manner as in Comparative Example 2 to form an uncoated portion having a width of 5 cm, and the same drying as in Example 3 was performed.
A negative electrode sheet having a thickness of 100 μm was prepared under the roller press conditions.

Comparative Example 7 0.1 P was prepared by changing the amount of water added to the positive electrode material of Example 1.
An electrode material coating solution of as was prepared, and coating, drying and roller pressing were performed in the same manner as in the positive electrode of Example 1, and the uncoated portion width was 3c.
A positive electrode sheet having a thickness of m and a thickness of 370 μm was prepared. The negative electrode sheet was prepared in the same manner as in Example 1. Comparative Example 8 0.1 P was obtained by changing the amount of water added to the positive electrode material of Example 2.
An electrode material coating solution of as was prepared, and coating, drying and roller pressing were performed in the same manner as the positive electrode of Example 2, and the uncoated portion width 3c.
A positive electrode sheet having a thickness of m and a thickness of 370 μm was prepared. The negative electrode sheet was prepared in the same manner as in Example 2. Comparative Example 9 500P by changing the amount of water added to the positive electrode material of Example 1
An electrode material coating solution of as was prepared, and coating, drying and roller pressing were performed in the same manner as in the positive electrode of Example 1, and the uncoated portion width was 3c.
A positive electrode sheet having a thickness of m and a thickness of 370 μm was prepared. The negative electrode sheet was prepared in the same manner as in Example 1. Comparative Example 10 500P by changing the amount of water added to the positive electrode material of Example 2
An electrode material coating solution of as was prepared, and coating, drying and roller pressing were performed in the same manner as the positive electrode of Example 2, and the uncoated portion width 3c.
A positive electrode sheet having a thickness of m and a thickness of 370 μm was prepared. The negative electrode sheet was prepared in the same manner as in Example 2.

[0022]

[Table 1]

Using the electrode sheets prepared in Examples and Comparative Examples, 50 cylindrical batteries were prepared and the discharge capacity was measured. The length of each electrode sheet was 25 cm, the diameter of the cylindrical battery was 1.4 cm, and the height was 5 cm. Regarding the discharge capacity, the average discharge capacity of the battery prepared by combining the positive electrode sheet and the negative electrode sheet prepared in Example 1 was set to 100, and
7, 8, 9, 10 and Comparative Examples 1, 2, 7, 8, 9, 10 were evaluated. In Example 4 and Comparative Examples 3 and 4, the discharge capacity of Example 3 was set to 100, and in Example 6 and Comparative Examples 5 and 6, the discharge capacity of Example 5 was set to 100. In Examples 1 to 10 and Comparative Examples 2, 4, 6, 9, and 10, smooth coating surfaces could be obtained, but in the gravure method of Comparative Examples 1, 3, and 5,
Since a part of the electrode material coating solution remained in the cell portion and the coating solution could not be completely transferred, unevenness appeared on the coated surface and the surface was not smooth. In Comparative Examples 7 and 8 using the extrusion type liquid injector 21, the positive electrode material is the liquid reservoir 2.
No sedimentation occurred within 0, the state of dispersion was poor, and the discharge of the electrode material coating liquid from the slot nozzle was non-uniform, and a smooth surface could not be obtained. The shape of the uncoated portion is shown in FIG. Examples 1 to 1
In 0 and Comparative Examples 1, 3, 5, 7, and 8, the boundary between the coated portion and the uncoated portion was substantially linear, but in the doctor blade system of Comparative Examples 2, 4, and 6, the coated portion was substantially linear. However, the end of coating was wavy as shown in FIG. 5 (D). When the width of the wavy portion is measured, it is 3 to 10 mm.
there were. Further, in Comparative Examples 9 and 10 using the extrusion type liquid injector, a smooth coating surface could be obtained, but the coating end portion was wavy as shown in FIG. 5 (D). The width of the wavy portion was 4 to 9 mm. When the relationship between the uncoated part and the shape of the uncoated part was linear, no defects were found in the uncoated part because the lead welding strength was insufficient and the winding shape defect occurred in the assembly process. There was a response to the poor shape of the boundary and the incidence of defective assembly process. In order to maintain the suitability for battery assembly, it is necessary to apply the non-applied portion and to finish the application in a substantially straight line. Furthermore, as a result of measuring the discharge capacity of the battery, in the gravure coating method of Comparative Examples 1, 3 and 5, a part of the electrode material coating liquid remained on the roller and was not transferred, so the amount of active material was reduced and the discharge capacity was remarkably reduced. . Further, in the doctor method of Comparative Examples 2, 4, and 6, there was a decrease in the thickness of the coating and the liquid draining portion, and particularly the thickness of the liquid draining portion was greatly reduced, and the discharge capacity was reduced by 3 to 5%.

[0024]

According to the present invention, the discharge capacity becomes stable,
It is possible to provide an uncoated portion, which is an electrode material portion required for lead welding, at a right angle to the running direction of the conductive support, and it is possible to suppress the occurrence of defects in the assembly process. As a result, the welded portion of the lead plate can be formed without scraping off the electrode material once applied, and the electrode can be continuously supplied to the welder, thus improving the processing capacity of the welder. In addition to being able to do so, it is possible to reduce the number of man-hours and improve the efficiency of the process by suppressing process defects and reducing the number of work steps.

[Brief description of drawings]

FIG. 1 shows a main part of a coating apparatus used in the present invention.

FIG. 2 shows a coating machine used in the present invention.

FIG. 3 shows a coating apparatus used in the present invention.

FIG. 4 shows a doctor blade system.

FIG. 5 shows the shapes of uncoated portions of Examples and Comparative Examples.

[Explanation of symbols]

14 Conductive support 15 Backup roll 16 entrance lip 17 Exit side lip 18 slots 19 slot nozzle 20 liquid reservoir 21 Injector 22 Slot entrance 23 Constant flow rate liquid sending device 24 flow meter 25 filter 26 three-way valve 27 tanks 28 doctor blade 29 Shutter part 30 air cylinders 41 Application section 42 Welded part (uncoated part) 43 Width of uncoated part 44 Sending part 45 winding part 46 Drying room 47 Wavy width

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP 62-95169 (JP, A) JP 63-80872 (JP, A) JP 60-203442 (JP, A) JP 8- 37005 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01M 4/02-4/04 H01M 10/00-10/40

Claims (3)

(57) [Claims] 1. A method for forming an uncoated portion in a direction perpendicular to the running direction of a conductive support, wherein the viscosity of the electrode material coating solution is
Is 0.5 Pas to 300 Pas, and supply and stop of the supply of the electrode material coating solution to the extrusion type liquid injector having the slot nozzle are repeated, and / or the tip of the slot nozzle and the conductive support that runs. A method for manufacturing an electrode for a chemical battery, characterized in that the distance is repeatedly changed. 2. The production of an electrode for a chemical battery according to claim 1, wherein the chemical battery is a non-aqueous electrolyte battery.
Method. 3. A non-aqueous electrolyte battery using the electrode manufactured by the method according to claim 1 .