KR20130044160A - Electrode, electrode manufacturing apparatus and electrode manufacturing method - Google Patents

Abstract

PURPOSE: An electrode is provided to maintain electrode performance after repeating charging and discharging by having high adhesion between a current collector and an electrode layer. CONSTITUTION: An electrode is that an electrode layer overlaps a current collector(101,201). In the overlapped region, the concentration of binder components is higher than that in the surface layer side region. In 1/4 point from the overlapped region, if the total thickness of the electrode layer, 20-40% peak intensity is shown within a specific wavelength.

Description

ELECTRODE, ELECTRODE MANUFACTURING APPARATUS AND ELECTRODE MANUFACTURING METHOD}

TECHNICAL FIELD This invention relates to an electrode, an electrode manufacturing apparatus, and an electrode manufacturing method.

Lithium ion secondary batteries have a high power storage density and are well maintained as a power storage device even after repeated charging and discharging, and thus are widely used as power sources for automobiles and home appliances.

In the electrode formation process of a lithium ion secondary battery, first, the electrode slurry containing an active material, a binder, an electroconductivity agent, and a solvent is fixed weight on the electrical power collector, such as aluminum foil of a positive electrode, and copper foil of a negative electrode, for example. Apply. Next, in the drying furnace, the solvent contained in the electrode slurry is evaporated to dryness, and the electrode layer and the current collector, which are solid contents of the electrode slurry, are fixed by the binder. Then, the collector which presses an electrode layer as needed is pressed, the said pressed collector is cut | disconnected to a predetermined magnitude | size as needed, and the electrode which overlaps an electrode layer with a collector is manufactured.

In the process of drying the said electrode, the method of spraying hot air from the upper and lower surfaces of an electrical power collector in a drying furnace is common. As a main thing of the drying conditions in the case of hot air, there is a temperature of hot air, the amount of hot air blown out, and a drying time, and the method of setting and drying drying conditions is known conventionally (for example, refer patent document 1).

Japanese Patent Application Publication No. 2006-107780

When drying the electrode slurry described above, if the drying conditions (temperature of hot wind and hot air blowing amount in the case of hot wind) are largely changed, the microstructure inside the electrode layer may be affected, and electrode performance may be degraded. . This is because when the temperature of the hot air is raised to a high temperature or the amount of hot air is increased, the binder component in the electrode slurry moves from the core portion of the electrode layer to the surface of the electrode layer (hereinafter sometimes referred to as segregation), so that sufficient binding between the current collector and the electrode layer is achieved. This is due to the absence of ash components. In the drying method of patent document 1, for the said reason, the electrode which induces the fall of electrode performance may be manufactured.

This invention is made | formed in order to solve the said subject, Comprising: Providing the electrode, an electrode manufacturing apparatus, and an electrode manufacturing method which can maintain electrode performance even if a collector and electrode layer have sufficient adhesive state and repeats charging / discharging. The purpose.

The electrode which concerns on this invention which achieves the said objective is an electrode in which an electrode layer overlaps an electrical power collector, and the area | region on the side in which the electrical power collector of an electrode layer overlaps is compared with the area | region of the surface layer side opposite to the side where the said electrical power collector overlaps, It is an electrode with high component concentration of the binder contained in the said electrode layer.

In the case of the electrode configured as described above, the region on the side where the current collector of the electrode layer overlaps has high component concentration of the binder, so that the adhesive strength between the current collector and the electrode layer is improved. For this reason, not only the resistance value in a battery at the beginning of use but also the resistance value in a battery after repeating charge / discharge can be kept low, and electrode performance can be maintained. In addition, even when the electrolyte layer is infiltrated and the electrode layer is swollen, the adhesion strength between the current collector and the electrode layer is high, so that the electrode layer does not peel off from the current collector, so that the DC resistance value of the electrode does not increase and the electrode performance can be maintained.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic block diagram which shows the electrode manufacturing apparatus which concerns on this invention.
Fig. 2 is a schematic diagram showing the state change of the electrode slurry of the positive electrode when the coating layer is dried by the drying method of the present embodiment, (a) after completion of the preheating step, and (b) for constant rate. (C) is a figure which shows the state of the electrode slurry after completion | finish of a reduction rate process after completion | finish of an evaporation process, respectively.
Fig. 3 is a schematic diagram showing the state change of the electrode slurry of the negative electrode when the coating layer is dried by the drying method of the present embodiment, (a) after completion of the preheating step and (b) after completion of the constant evaporation step. (C) is a figure which shows the state of the electrode slurry after completion | finish of a reduction rate process, respectively.
FIG. 4 is a schematic configuration diagram illustrating one of the drying zones in FIG. 1. FIG.
5 is a schematic perspective view showing a porous plate nozzle of an electrode manufacturing apparatus according to the present invention.
6 is a schematic configuration diagram showing an infrared heating element of an electrode manufacturing apparatus according to the present invention.
7 is a flowchart of a method for manufacturing an electrode using the manufacturing apparatus according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In addition, in description of drawing, the same number is attached | subjected to the same element, and the overlapping description is abbreviate | omitted. The dimension ratio of drawing is exaggerated for convenience of description, and differs from an actual ratio.

As shown in FIG. 1, the electrode manufacturing apparatus 1 according to the embodiment of the present invention conveys the current collectors 101 and 201, and collects the electrode slurry 110, 210 containing the active material. , 201), and the formed coating layer is dried in a drying furnace 30 to be described later to produce an electrode in which the electrode layers overlap the current collectors 101 and 201.

First, the electrode manufactured by the electrode manufacturing apparatus 1 which concerns on this embodiment is demonstrated.

The electrode has a positive electrode 100 and a negative electrode 200.

As shown in FIG. 2A, the positive electrode 100 includes a positive electrode active material 111, a binder 112, a conductivity providing agent 113, and a solvent 114 in the positive electrode current collector 101. It is manufactured by apply | coating the positive electrode slurry 110 (henceforth a following may be called a positive electrode slurry), and drying the solvent 114 in the positive electrode slurry 110. FIG.

Similarly, as shown in FIG. 3A, the negative electrode 200 is connected to the negative electrode current collector 201 by the negative electrode active material 211, the binder 212, the conductivity giving agent 213, and the solvent 214. It is manufactured by apply | coating the negative electrode slurry 210 (Hereinafter, it may be called a negative electrode slurry) which has a, and drying the solvent 214 in the negative electrode slurry 210. FIG.

As the current collectors 101 and 201, a suitable material, aluminum, copper, nickel, iron, stainless steel, etc. can be used. Specifically, for example, a material such as aluminum may be used for the positive electrode current collector 101, and a material such as copper may be used for the negative electrode current collector 201. Although there is no restriction | limiting in particular about the specific thickness of the electrical power collectors 101 and 201, For example, it is a thin film about 20 micrometers in case of aluminum, and about 10 micrometers in case of copper.

The positive electrode slurry 110 has, for example, a positive electrode active material 111, a binder 112, and a conductivity providing agent 113, and is set to a predetermined viscosity by adding a solvent 114. The positive electrode active material 111 is lithium manganate, for example. The binder 112 is PVDF (polyvinylidene fluoride), for example. The conductivity giving agent 113 is acetylene black, for example. The solvent 114 is, for example, NMP (normal methylpyrrolidone). In addition, although the positive electrode active material 111 is not specifically limited to lithium manganate, it is preferable to apply a lithium transition metal complex oxide from a viewpoint of a capacity | capacitance and an output characteristic. For example, carbon black or graphite may be used for the conductivity providing agent 113. The binder 112 and the solvent 114 are not limited to PVDF and NMP. Water may be used as the solvent 114.

The negative electrode slurry 210 has, for example, a negative electrode active material 211, a binder 212, and a conductivity providing agent 213, and has a predetermined viscosity by adding a solvent 214. The negative electrode active material 211 is, for example, graphite. The binder 212 is PVDF (polyvinylidene fluoride), for example. The conductivity giving agent 213 is acetylene black, for example. The solvent 214 is NMP (normal methylpyrrolidone), for example. In addition, the negative electrode active material 211 is not specifically limited to graphite, It is also possible to use hard carbon and a lithium-transition metal composite oxide. For example, carbon black or graphite may be used for the conductivity providing agent 213. The binder 212 and the solvent 214 are not limited to PVDF and NMP. Water may be used as the solvent 214.

The positive electrode 100 and the negative electrode 200 have the following characteristics.

As shown in FIG.2 (c) and FIG.3 (c), the electrode slurry 110,210 is dried by the electrode manufacturing method mentioned later, and the electrical power collectors 101 and 201 of the electrode layers 103 and 203 are dried. ), The component concentration of the binders 112 and 212 becomes higher than the region on the surface layer side opposite to the side where the current collectors 101 and 201 overlap.

In addition, when the thickness of the whole electrode layers 103 and 203 is set to 1, in the vicinity of the collector A01, which is an area from the side where the current collectors 101 and 201 of the electrode layers 103 and 203 overlap to one quarter, respectively. , 20 to 40% of the total integral strength is present.

Here, the definition of the integral strength and the measuring method will be described. When the binders 112 and 212 are measured by Raman spectroscopy, a peak appears at a specific wavelength. For example, the electrode is cut and cut out in the cross sections of the electrode layers 103 and 203, and in the region of 120 mu m thickness and 100 mu m width from the current collectors 101 and 201 to the surface layer of the electrode layers 103 and 203. When Raman was measured, the peaks of the binders 112 and 212 appeared in each part of the said surface of 120 micrometers x 100 micrometers, and the intensity | strength of this peak is integrated and it is set as the total integrated intensity. In addition, the distance from the current collectors 101 and 201 to the surface layers of the electrode layers 103 and 203 is divided into four to be a quarter from the side where the current collectors 101 and 201 of the electrode layers 103 and 203 overlap. The integral intensity of the peak of the region is calculated and the relative intensity is calculated by dividing this value by the total integral intensity.

Further, the current collector neighborhood A01 is an electrode layer 103 than the electrode layer surface neighborhood A02 which is an area from the surface layer side to a quarter opposite to the side where the current collectors 101, 201 of the electrode layers 103, 203 overlap. , The integrated strength of the binders 112 and 212 contained in 203 is high.

By having the above characteristics, the component concentration of the binders 112 and 212 in the vicinity of the current collector A01 is increased, so that the adhesion strength between the current collectors 101 and 201 and the electrode layers 103 and 203 is improved. Thus, a high performance electrode can be provided.

The negative electrode 200 further has the following characteristics.

As shown in FIG.3 (c), by drying the negative electrode slurry 210 by the electrode manufacturing method mentioned later, in the electrode layer surface layer vicinity A02, it is an area | region from 1/4 to 1 with respect to the surface layer side. The concentration of the conductivity giving agent 213 is higher than that of the electrode layer center portion A03. This is because in the negative electrode 200, amorphous carbon such as acetylene black (specific gravity: 1.9) added as the conductivity giving agent 213, compared to the crystalline carbon such as graphite (specific gravity: 2.2) used as the negative electrode active material 211. This is because the smaller the specific gravity, the more easily the conductivity imparting agent 213 moves to the surface layer of the electrode layer 203 together with the evaporation of the solvent 214.

In addition, the negative electrode 200 is 2.0≥ when the average D / G value, which is the intensity ratio of the peak of the D band to the G band of carbon measured by Raman spectroscopy, is Rs in the vicinity of the electrode layer A02 and Rb in the center of the electrode layer A03. It satisfies the relationship between Rs / Rb. This means that when the conductivity giving agent 213 moves to the surface layer of the electrode layer 203 as described above, an upper limit is set on the movement amount.

That is, the average D / G value correlates with the graphitization degree (large and small crystallinity), and the smaller the D / G value, the higher the graphitization degree, that is, the higher the crystallinity. As described above, in the negative electrode 200, amorphous carbon (small in graphitization degree) applied as the conductivity imparting agent 213 may move to the surface layer side of the electrode layer 203 in the evaporation step. Under the present circumstances, by setting it as 2.0≥Rs / Rb by the electrode manufacturing method mentioned later, it can suppress excessive movement of amorphous carbon to the surface layer side of the electrode layer 203, and can maintain high adhesive strength.

By having the above characteristics, the adhesive strength between the collector 201 and the electrode layer 203 can be improved, and the high-performance negative electrode 200 can be provided.

Next, the electrode manufacturing apparatus 1 which concerns on this embodiment is demonstrated. Here, the positive electrode 100 will be described as an example.

As shown in FIG. 1, the electrode manufacturing apparatus 1 includes a conveying part 10 for conveying the current collector 101 and an applicator 20 for applying the electrode slurry 110 to the current collector 101. And a drying furnace 30 for drying the electrode slurry 110. It will be described in detail below.

The conveyance part 10 is the winding roll which winds up the supply roll 11 which supplies the collector 101 before apply | coating the electrode slurry 110, and the collector 101 after drying the electrode slurry 110. FIG. It has the 12 and the motor M which drives the winding roll 12 to rotate. The conveyance part 10 also has the some support roll 13 arrange | positioned between the supply roll 11 and the winding roll 12, and holding the lower surface of the electrical power collector 101. As shown in FIG. The strip-shaped current collector 101 is wound in advance on the supply roll 11. When the motor M is driven and the winding roll 12 is driven to rotate, the current collector 101 is supplied from the supply roll 11, the inside of the drying furnace 30 is conveyed, and is wound by the winding roll 12. It is wound up. In this way, the conveyance section 10 continuously conveys the long current collector 101.

Application | coating to the electrical power collector 101 of the electrode slurry 110 is performed by the application | coating part 20, conveying the electrical power collector 101. FIG. The coating unit 20 has a coater 21 for applying the electrode slurry 110 to the current collector 101. The coater 21 is disposed to face the current collector 101, and intermittently applies the electrode slurry 110 to the current collector 101 being conveyed.

As shown in FIG. 4, the drying furnace 30 includes a casing 31 for forming a conveying path for the current collector 101, a hot air generating unit 32 for generating hot air, and a hot air generating unit 32. The upper nozzle 33 which spouts hot air from the upper part of the application layer 102 of the electrode slurry 110, and the hot air from the hot air generation | generation part 32 are lower part of the application layer 102 of the electrode slurry 110. It has a lower nozzle 34 which blows out into the furnace. 4, the 1st drying zone 36 mentioned later is shown. In the drying furnace 30, partition walls 35 are provided in the casing 31 to form drying zones 36 to 41 partitioned into a plurality (6 in FIG. 1). For convenience of explanation, the six drying zones 36 to 41 are sequentially ordered from the upstream side in the direction of conveying the current collector 101 (from the left in FIG. 1), the first drying zone 36 and the second drying zone. (37), the 3rd dry zone 38, the 4th dry zone 39, the 5th dry zone 40, and the 6th dry zone 41 are defined.

In the 1st dry zone 36 and the 2nd dry zone 37, the preheating process S04 which preheats the electrode slurry 110 is performed.

In the 3rd dry zone 38 and the 4th dry zone 39, the constant evaporation process S05 of which the drying rate of the electrode slurry 110 is constant is performed.

In the 5th dry zone 40 and the 6th dry zone 41, the reduction rate evaporation process S06 which carries out the gradually decreasing rate of drying of the electrode slurry 110 depends on the decrease of the solvent content rate of the electrode slurry 110, is implemented. do.

As illustrated in FIG. 4, the hot air generator 32 connects the first piping 44 connecting the air supply fan 42 and the circulation fan 43, and the circulation fan 43 and the upper nozzle 33. 2nd piping 45 to which it is made, and the 3rd piping 46 which connects the circulation fan 43 and the lower nozzle 34 are provided. The hot air generator 32 further includes a fourth pipe 49 for connecting the exhaust port 47 and the exhaust fan 48 in the drying furnace 30, the circulation port 50 and the circulation fan in the drying furnace 30. The 5th piping 51 which connects 43 is provided. In addition, a heater 52 is provided between the air supply fan 42 and the circulation fan 43 for adjusting the temperature of the hot air to be supplied. In each of the pipes 44 to 46, 49, and 51, dampers 53 for adjusting the amount of hot air are provided. The temperature of the hot air is not particularly limited because it varies depending on the environment temperature, the type of the electrode slurry 110, and the like, but is, for example, 100 ± 40 ° C.

Hot air supplied from the air supply fan 42 passes through the first pipe 44 to reach the circulation fan 43. At this time, the air volume of the hot air is adjusted by the damper 53, and the temperature of the hot air is adjusted by the heater 52. The hot air which exited the circulation fan 43 is distributed to the 2nd piping 45 and the 3rd piping 46. The amount of air blown by the damper 53 is adjusted by the damper 53 to reach the upper nozzle 33. On the other hand, the air volume distributed to the third pipe 46 is adjusted by the damper 53 to reach the lower nozzle 34. Hot air reaching the upper and lower nozzles 33 and 34 is ejected from the upper and lower nozzles 33 and 34 to the electrode slurry 110, respectively. As shown in FIG. 5, the upper nozzle 33 is a porous plate-shaped nozzle having a hole 54, and has an opening ratio of 10% or more. The hot air blown out of the upper and lower nozzles 33 and 34 is divided into hot air discarded as exhaust and hot air circulating again in the hot air generating unit 32 for reuse. The hot air discarded as the exhaust gas passes through the fourth pipe 49 from the exhaust port 47 provided in the drying furnace 30, reaches the exhaust fan 48, and is exhausted by the exhaust fan 48. At this time, the air volume is adjusted by the damper 53. In addition, the hot air circulated again passes through the fifth pipe 51 from the circulation port 50 provided in the drying furnace 30 and reaches the circulation fan 43. At this time, the air volume is adjusted by the damper 53, and the temperature is adjusted again by the heater 52. In addition, as shown in FIG. 4, FIG. 6, as a structure of the hot air generation | generation part 32, it has the infrared heat generating body 55 between the upper nozzles 33, and the infrared heat generating body 55 generates heat by the power supply P. As shown in FIG. In order to prevent explosion, the cooling air C is cooled from the surroundings.

Moreover, the electrode manufacturing apparatus 1 has the controller 56 which controls the operation | movement of the application part 20. As shown in FIG. The controller 56 mainly consists of a CPU and a memory, and a program for controlling the operation is stored in the memory. The controller 56 controls the operation of the application unit 20, adjusts the application amount, the application thickness of the electrode slurry 110, and the like, and also controls the operation of the hot air generation unit 32 to control the temperature and air volume of the air supply. And so on. The controller 56 also controls the operation of the motor M to adjust the conveyance speed of the current collector 101.

Before demonstrating the manufacturing method of the electrode using the electrode manufacturing apparatus 1 which concerns on this embodiment, the phenomenon which arises when the temperature and air volume of the air supply to the drying furnace 30 are changed largely is demonstrated. Here, the positive electrode 100 will be described as an example.

In the drying furnace 30 using the hot air, the hot air temperature is increased and the air volume is increased to increase the removal amount of the solvent 114 in the surface portion of the coating layer 102, thereby improving the drying speed. Can be. By the way, according to this drying method, drying accelerates and the binder 112 segregates in the vicinity of the surface of the electrode layer 103. For this reason, it becomes difficult to obtain the coating film which adhered strongly to the electrical power collector 101, ie, the strong adhesion electrode layer 103. FIG.

As a cause which the segregation of the binder 112 generate | occur | produces when raising hot air temperature, the following are mentioned. At the time of drying, since the thing which melt | dissolved the binder 112 in the solvent 114 is contained in the application layer 102, when the application layer 102 is exposed to the environment of high temperature, it is a solvent in the application layer 102. (114) It causes convection itself. As a result, the binder 112 melt | dissolved segregates.

Moreover, the following are mentioned as a cause which the segregation of the binder 112 generate | occur | produces when the air volume is increased. Only the solvent 114 in the vicinity of the surface of the coating layer 102 is preferentially volatilized, and only the vicinity of the surface is dried first, and by the capillary phenomenon caused by cracks or holes generated in the surface dry portion, the solvent ( 114) from the core towards the surface. As a result, the binder 112 melt | dissolved segregates.

In the drying conditions that can cause segregation of the binder 112 at the time of drying, the surface roughness of the electrode layer 103 is large and the adhesion is weak, so that the contact amount or the contact area between the current collector 101 and the electrode layer 103 is reduced. Is less. For this reason, not only the resistance value in a battery at the beginning of use but also the resistance value in a battery after repeating charge / discharge will become high, and will lead to the fall of electrode performance.

In order to eliminate the segregation of the generated binder 112, there is a method of compressing the electrode 100 after drying by a roll press or the like. However, since drying is completed and the structure is forcibly changed after the electrode layer 103 is fixed, the adhesion strength of the electrode layer 103 does not improve so much. In addition, from the viewpoint of mass production at low cost, it is preferable to avoid adding a compression step after the drying step.

Next, the manufacturing method of the electrode using the electrode manufacturing apparatus 1 which concerns on this embodiment is demonstrated based on the flowchart of FIG. Here, the positive electrode 100 will be described as an example.

Current collector conveyance process S01 is a process of conveying the electrical power collector 101. In current collector conveyance process S01, the motor M is driven to rotate and drive the winding roll 12, the current collector 101 is fed out from the supply roll 11, and is wound up by the winding roll 12. FIG. The controller 56 controls the operation of the motor M to adjust the conveyance speed.

Coating process S02 is a process of apply | coating the electrode slurry 110 containing the active material 111, the binder 112, the electroconductive agent 113, and the solvent 114 to the electrical power collector 101. FIG. The coater 21 arranged to face the current collector 101 applies the electrode slurry 110 intermittently to the surface of the current collector 101 that is moving. The controller 56 controls the operation of the coating unit 20 to adjust the coating amount, the coating thickness, and the like of the electrode slurry 110.

Hot air generation step S03 is a step of generating hot air for drying the electrode slurry 110. In the hot air generation step S03, the hot air supplied from the air supply fan 42 is adjusted by the heater 52 to reach the circulation fan 43. The hot air exiting the circulation fan 43 is separated to reach the upper and lower nozzles 33 and 34.

In the preheating step S04, hot air is blown out from the upper and lower nozzles 33 and 34 to the electrode slurry 110 or the infrared heating element 55 is provided so that the amount of heat until the evaporation of the slurry before the carry-in into the drying step is started. The heat is applied to the electrode slurry 110 by this. The supply amount of specific heat quantity is computed by the procedure of actually giving the hot air of a specific temperature and air volume repeatedly, and confirming evaporation amount several times, and quantifying an appropriate temperature and air quantity. The controller 56 controls the heater 52, various fans 42, 43, 48 and the like to adjust the temperature of the hot air, the amount of air and the like. Preheating process S04 is performed in the 1st drying zone 36 and the 2nd drying zone 37. FIG. When this process is complete | finished, the amount of solvent which remains in the electrode slurry 110 is 100 to 90 weight%.

In constant-rate evaporation process S05, hot air is moved up-and-down nozzle 33 so that the solvent 114 may be evaporated and removed, suppressing the movement of the component of the binder 112 and the electroconductivity imparting agent 113 resulting from evaporation of the solvent 114. 34 is injected into the electrode slurry 110 or heat is applied to the electrode slurry 110 by the infrared heating element 55. The constant evaporation step S05 is performed in the third drying zone 38 and the fourth drying zone 39. When this process is complete | finished, the amount of solvent which remains in the electrode slurry 110 is 95 to 1 weight%.

In the reduction rate evaporation step S06, the electrode slurry 110 is concentrated, so that the movement of the component of the binder 112 and the conductivity providing agent 113 hardly occurs. For this reason, hot air is blown out from the up-and-down nozzles 33 and 34 to the electrode slurry 110, or heat is heated to the electrode slurry 110 by the infrared heating element 55 so as to rapidly evaporate and remove the remaining solvent 114. To give. Reduction rate evaporation process S06 is performed in the 5th dry zone 40 and the 6th dry zone 41. FIG. When this process is complete | finished, the amount of solvent which remains in the electrode slurry 110 is 0.1 weight% or less.

In the above-described steps S04 to S06 (hereinafter, the steps S04 to S06 may be referred to as a drying step), the electrode slurry 110 is dried under conditions not causing segregation of the binder 112. Therefore, the adhesion between the current collector 101 and the electrode layer 103 is improved, and the resistance value in the battery at the beginning of use, as well as the resistance value in the battery after repeated charging and discharging are lowered, thereby improving electrode performance. It becomes possible. In addition, appropriate temperature conditions can be set in the drying step, which leads to a shortening of the drying time as a whole.

Step S07 is a step of exhausting and circulating hot air. The hot air blown out to the electrode slurry 110 is divided into hot air discarded as exhaust and hot air circulating through the hot air generating unit 32 for reuse. The hot air discarded as exhaust is exhausted by the exhaust fan 48 from the exhaust port 47 provided in the drying furnace 30. In addition, the temperature of the hot air for reuse is adjusted by the heater 52, reaches the circulation fan 43 again, and is reused.

As described above, the electrode according to the present embodiment is an electrode in which the electrode layers 103 and 203 overlap the current collectors 101 and 201, and the current collectors 101 and 201 of the electrode layers 103 and 203 overlap each other. The region on the side is an electrode having a higher component concentration of the binders 112 and 212 included in the electrode layers 103 and 203 than the region on the surface layer side opposite to the side where the current collectors 101 and 201 overlap. For this reason, the adhesive strength of the electrical power collectors 101 and 201 and the electrode layers 103 and 203 becomes high. Therefore, not only the resistance value in the battery at the beginning of use but also the resistance value in the battery after repeated charging and discharging are lowered, thereby improving battery performance. In addition, even when the electrolyte layers seep into the electrode layers 103 and 203 and the binders 112 and 212, the adhesion strengths of the current collectors 101 and 201 and the electrode layers 103 and 203 are high. ) Does not peel off from the current collectors 101 and 201, so that the DC resistance value of the electrode does not increase, and battery performance can be maintained.

When the thickness of the entire electrode layers 103 and 203 is 1, 20 to 40% of the integral strength of all the binders 112 and 212 is present in the vicinity of the current collector A01. For this reason, the adhesive strength of the electrical power collectors 101 and 201 and the electrode layers 103 and 203 can be raised reliably.

Further, the current collector neighborhood A01 is a binder (compared to the electrode layer surface layer neighborhood A02, which is an area from the surface layer side to 1/4 opposite to the side where the current collectors 101, 201 of the electrode layers 103, 203 overlap. 112, 212) have a high integration intensity. For this reason, the adhesive strength of the electrical power collectors 101 and 201 and the electrode layers 103 and 203 can be raised reliably.

In addition, in the electrode layer surface layer vicinity A02, there is a region having a higher concentration of the conductivity-imparting agents 113 and 213 than the electrode layer center portion A03 which is a region from 1/4 to 1 on the surface layer side as a reference. For this reason, the component concentration of the binders 112 and 212 in the vicinity A01 of an electrical power collector becomes relatively high, and the adhesive strength of the electrical power collectors 101 and 201 and the electrode layers 103 and 203 becomes high.

In addition, when the average D / G value, which is the intensity ratio of the peak of the D band to the G band of carbon measured by Raman spectroscopy, is Rs in the vicinity of the electrode layer surface layer A02 and Rb in the electrode layer center portion A03, the relationship of 2.0 ≧ Rs / Rb. Satisfies For this reason, the conductivity providing agents 113 and 213 do not increase too much in the electrode layer surface layer side, and the adhesive strength of the electrical power collectors 101 and 201 and the electrode layers 103 and 203 becomes high.

As described above, the electrode manufacturing apparatus 1 according to the present embodiment includes the active materials 111 and 211, the binders 112 and 212, the conductivity giving agents 113 and 213, and the solvents 114 and 214. The coating layers 102 and 202 formed by applying the electrode slurries 110 and 210 containing the same to the current collectors 101 and 201 are dried in the drying furnace 30, and the electrode layers are applied to the current collectors 101 and 201. It is an electrode manufacturing apparatus 1 which manufactures the electrode in which (103,203) overlaps. The electrode manufacturing apparatus 1 is a porous plate nozzle in which a plurality of holes 54 are opened at an outlet of hot air for heating and drying the surfaces on which the coating layers 102 and 202 of the electrode slurry 110, 210 are formed by hot air. (Upper nozzle) 33, and the aperture ratio of the porous plate nozzle 33 is 10% or more. For this reason, the electrode slurry 110, 210 can be dried suitably in a drying process, and the density | concentration of the components of the binders 112 and 212 in the vicinity A01 of an electrical power collector becomes high, and the electrical power collectors 101 and 201 ) And the adhesion strength between the electrode layers 103 and 203 are increased.

Moreover, it has the infrared heat generating body 55 for heat-drying the surface in which the coating layers 102 and 202 of the electrode slurry 110 and 210 were formed. For this reason, the electrode slurry 110, 210 can be dried suitably in a drying process, and the density | concentration of the components of the binders 112 and 212 in the vicinity A01 of an electrical power collector becomes high, and the electrical power collectors 101 and 201 ) And the adhesion strength between the electrode layers 103 and 203 are increased.

As described above, the electrode manufacturing method according to the present embodiment is an electrode manufacturing method for manufacturing an electrode in which the electrode layers 103 and 203 overlap the current collectors 101 and 201, and the electrode slurries 110 and 210. Preheating step S04 for preheating, constant rate evaporation step S05 with a constant drying rate of the electrode slurry 110, 210, and a drying rate of the electrode slurry 110, 210 decreasing the solvent content rate of the electrode slurry 110, 210. Depending on, it has a decreasing rate evaporation process S06. For this reason, since the appropriate temperature conditions can be set in each process, drying time can be shortened as a whole and also leads to reduction of an installation.

In addition, in the preheating step S04, the constant evaporation step S05, and the reduction rate evaporation step S06, the amount of solvent remaining in the electrode slurry 110, 210 at the end of each step is 100 to 90% by weight and 95 to 1%, respectively. % In the range of 5% to 0.01% by weight. For this reason, the solvents 114 and 214 are dried suitably, and many binders 112 and 212 can exist in the vicinity of an electrical power collector, and the electrical power collectors 101 and 201 and the electrode layers 103 and 203 adhere | attach. Strength is increased.

In addition, the constant evaporation step S05 has a first constant evaporation step and a second constant evaporation step, and the amount of solvent remaining in the electrode slurries 110 and 210 at the end of each step is 95 to 65% by weight, respectively. It exists in the range of -1 weight%. For this reason, the solvents 114 and 214 are dried suitably, and many binders 112 and 212 can exist in the vicinity of the collector A01, and the collectors 101 and 201 and the electrode layers 103 and 203 are appropriate. Adhesion strength increases.

The amount of solvent remaining in the electrode slurries 110 and 210 after the reduction rate evaporation step S06 is completed is 0.1% by weight or less. For this reason, since the solvent 114 and 214 hardly remain after a drying process is completed, the adhesive strength of the electrical power collectors 101 and 201 and the electrode layers 103 and 203 becomes high.

(Change example)

Although the preheating process S04, the constant rate evaporation process S05, and the reduction rate evaporation process S06 which showed the form implemented in two drying zones each were shown in the drying zone 30, it is not limited to this form, but drying of each process is carried out. You can increase or decrease the number of zones.

In the present embodiment, as the configuration of the hot air generating unit 32, hot air emitted from the upper and lower nozzles 33 and 34 and the infrared heating element 55 are included, but either one may be present alone or another heat generation. You can also use the method.

In addition, in this embodiment, although the opening ratio of the upper nozzle 33 which blows out the hot air for drying the electrode slurry 110, 210 is made into 10% or more, it is not limited to this.

In this embodiment, although it has the 5th piping 51 for reusing the hot air blown out from the up-and-down nozzles 33 and 34, it is not necessary.

In addition, although the form which conveys the electrical power collectors 101 and 201 continuously in this embodiment was shown, the form which conveys by a batch type may be sufficient.

In addition, this invention is not limited to the case where the electrode slurry 110 and 210 is apply | coated intermittently, Of course, it can be applied also to the case of applying the electrode slurry 110 and 210 continuously.

Example

Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not limited only to these. In addition, 1st-8th, 17th, 18th Example, and 1st comparative example correspond to a positive electrode, 9th-16th example, and a 2nd comparative example correspond to a negative electrode.

[First Embodiment]

(Composition of Positive Electrode Slurry)

(Production of the positive electrode slurry)

The positive electrode slurry which has a composition of Table 1 was prepared as follows. First, 4.4 parts by weight of PVDF was dissolved in 30 parts by weight of NMP to prepare a PVDF solution. Next, 34.4 parts by weight of the PVDF solution was added to 4.4 parts by weight of a conductive imparting agent and 100 parts by weight of lithium manganate powder, and then added to a planetary mixer (manufactured by Asada Co., Ltd., PVM100). After kneading, 37 parts by weight of NMP was added to the kneaded material to obtain a positive electrode slurry (solid content concentration of 62% by weight).

(Application and Drying of Positive Electrode Slurry)

The said positive electrode slurry was apply | coated to the single side | surface of an electrical power collector by the coater, running a 20-micrometer-thick aluminum foil current collector at a traveling speed of 8 m / min.

Subsequently, a drying furnace (one block is 2.5 m, eight furnaces) in which the drying zone of the constant rate evaporation process is increased with respect to FIG. 1 and FIG. 4 (the distance D1 from the porous plate type upper nozzle to the foil is 10 to 150 mm). And the distance (D2) from the slit-type lower nozzle to the foil (10 to 75 mm)], and the positive electrode slurry was dried by the following drying step.

First, furnace temperature 135 degreeC of each zone of a preheating process (1st drying zone and 2nd drying zone), an upper nozzle (10% of opening ratio, D1: 50mm), and a lower nozzle (slit width: 5mm, D2: 10mm) ) Was heated on the conditions of 50 Nm <3> / min of total blowing air volume (43Nm <3> / min of circulating air volume, and 7Nm <3> / min of air quantity introduced from the outside).

Subsequently, furnace temperature 130 degreeC of each zone of a constant evaporation process (3rd to 6th drying zone), an upper nozzle (30% of opening ratio, D1: 50mm), and a lower nozzle (slit width: 5mm, D2: Constant evaporation was performed on the conditions of 100 Nm <3> of total blowing air volume of 10 mm) (circulating air volume of 10 Nm <3> / min, and 90 Nm <3> / min of air quantity introduced from the outside).

Moreover, furnace temperature 140 degreeC of each zone of a reduction ratio evaporation process (7th dry zone and 8th dry zone), an upper nozzle (10% of opening ratio, D1: 50mm), and a lower nozzle (slit width: 5mm, D2: 10) Reduction rate evaporation was performed on the conditions of 70 Nm <3> / min of total blow-out air volume (mmN) (circulating air volume 67Nm <3> / min, and 3Nm <3> / min of air quantity introduced from the outside).

The amount of NMP evaporated in each step was measured by the NMP concentration sensor provided at the top of each step, and the NMP content remaining in the coating layer (positive electrode slurry coated on the current collector) passing through each step was calculated.

As a result, the amount of evaporation NMP in the preheating step is 7% by weight (the amount of residual NMP is 93% by weight) and the amount of evaporation NMP in the constant rate evaporation step with respect to the amount of NMP (the amount of residual NMP is 100% by weight) carried into the drying furnace. The 88% by weight of silver (the amount of residual NMP was 5% by weight) and the amount of evaporation NMP in the reduction rate evaporation step were 4.97% by weight (the amount of residual NMP was 0.03% by weight).

In addition, when the rate reduction evaporation process was complete | finished, the NMP content which remains in the positive electrode layer was analyzed by gas chromatography, and it confirmed that it was 0.03 weight%.

Furthermore, the back surface of aluminum foil was apply | coated and dried on the conditions similar to the above, and the sheet-like electrode which has an electrode active material layer on both surfaces was formed. A roller press was applied to the sheet-shaped electrode, compression molded, and cut to prepare a positive electrode having a thickness of about 100 μm of the active material layer on one side. When the surface of the positive electrode was observed, no crack was observed.

In addition, the adhesive strength of the electrode active material layer after a press was carried out by the 90 degree tensile test [tester: The product made by Ida Seisakusho, a model number: SV-52NA-20M, the load cell maximum load: 200N, a tension rate: 100] Mm / min, and a sample piece: 15 mm x 80 mm].

[Second Embodiment]

(Composition of Positive Electrode Slurry)

(Production of the positive electrode slurry)

The positive electrode slurry which has a composition of Table 2 was prepared according to the 1st Example.

(Application and Drying of Positive Electrode Slurry)

According to the first embodiment, the positive electrode slurry was applied to a single side of a 20 μm aluminum foil current collector by a coater.

Subsequently, the positive electrode slurry was dried by the following drying step.

First, the total blowing air volume 25Nm3 / of the furnace temperature 135 degreeC of a preheating process (1st drying zone), an upper nozzle (10% of opening ratio, D1: 25mm), and a lower nozzle (slit width: 5mm, D2: 10mm) min (circulating air volume 25Nm3 / min), furnace temperature 135 degreeC of a preheating process (2nd drying zone), an upper nozzle (10% of opening ratio, D1: 50mm), and a lower nozzle (slit width: 5mm, D2: 10mm) ), The temperature was raised under the conditions of 25 Nm 3 / min of total blowing air volume (20Nm 3 / min of circulating air volume and 5Nm 3 / min of air introduced from the outside).

Subsequently, furnace temperature 125 degreeC of each zone of a constant evaporation process (3rd to 6th dry zone), an upper nozzle (30% of opening ratio, D1: 50mm), and a lower nozzle (slit width: 5mm, D2: The constant evaporation was performed on the conditions of 100 Nm <3> / m of total blowing air volume (10 mm) (circulating air volume 8Nm <3> / min, and 92 Nm <3> / min of air quantity introduced from the outside).

Moreover, furnace temperature 140 degreeC of each zone of a reduction ratio evaporation process (7th dry zone and 8th dry zone), an upper nozzle (10% of opening ratio, D1: 25mm), and a lower nozzle (slit width: 5mm, D2: 10) Reduction rate evaporation was performed on the conditions of 70 Nm <3> / min of total blow-out air volume (mmN) (circulating air volume 67Nm <3> / min, and 3Nm <3> / min of air quantity introduced from the outside).

As a result, the amount of evaporation NMP in the preheating step is 5% by weight (the amount of residual NMP is 95% by weight) and the amount of evaporation NMP in the constant rate evaporation step with respect to the amount of NMP (the amount of residual NMP is 100% by weight) carried into the drying furnace. 92 weight% of silver (the amount of residual NMP was 3 weight%) and the amount of evaporation NMP in the reduction rate evaporation process were 2.97 weight% (the amount of residual NMP was 0.03 weight%).

In addition, when the rate reduction evaporation process was complete | finished, the NMP content which remains in the positive electrode layer was analyzed by gas chromatography, and it confirmed that it was 0.03 weight%.

Moreover, according to the 1st Example, the surface of the positive electrode was observed and the adhesive strength of the electrode active material layer after press was measured.

Third Embodiment

According to the first embodiment, the positive electrode slurry was coated on one side of the current collector with a coater while running a 20 μm thick aluminum foil current collector at a traveling speed of 12 m / min.

Subsequently, the positive electrode slurry was dried by the following drying step.

First, the total blowing air volume of the furnace temperature of 135 degreeC, upper nozzle (10% of opening ratio, D1: 25mm) of a preheating process (1st drying zone), and lower nozzle (slit width: 5mm, D2: 10mm) 30Nm <3> / min (circulating air volume 30Nm3 / min), furnace temperature 135 degreeC of a preheating process (2nd drying zone), an upper nozzle (10% of opening ratio, D1: 25mm), and a lower nozzle (slit width: 5mm, D2: 10mm) ), The temperature was raised under the condition of 40 Nm 3 / min of total blowing air volume (circulating air volume 25Nm 3 / min and 15Nm 3 / min of air introduced from the outside).

Subsequently, furnace temperature 130 degreeC of each zone of a constant evaporation process (3rd to 6th dry zone), an upper nozzle (30% of opening ratio, D1: 15mm), and a lower nozzle (slit width: 5mm, D2: Constant evaporation was performed on the conditions of the total blowing air volume of 150 mm <3> / m (10 mm) (circulating air volume of 20 Nm <3> / min, and 130 Nm <3> / min of air quantity introduced from the outside).

Moreover, furnace temperature 140 degreeC of each zone of a reduction ratio evaporation process (7th dry zone and 8th dry zone), an upper nozzle (10% of opening ratio, D1: 15mm), and a lower nozzle (slit width: 5mm, D2: 10) Reduction rate evaporation was performed on the conditions of the total blowing air volume of 80 Nm <3> / min (circle air volume of 70 Nm <3> / min, and 10 Nm <3> / min of air amount taken in from outside) of the total blowing air volume of mm).

As a result, the amount of evaporation NMP in the preheating step is 4% by weight (the amount of residual NMP is 96% by weight) and the amount of evaporation NMP in the constant rate evaporation step with respect to the amount of NMP (residual NMP amount is 100% by weight) carried into the drying furnace. The 93% by weight of silver (the amount of residual NMP was 3% by weight) and the amount of evaporation NMP in the reduction rate evaporation step were 2.97% by weight (the amount of residual NMP was 0.03% by weight).

Moreover, when NMP content which remained in the positive electrode layer when the reduction rate evaporation process was complete | finished was analyzed by gas chromatography, it was confirmed that it is 0.03 weight%.

Moreover, according to the 1st Example, the surface of the positive electrode was observed and the adhesive strength of the electrode active material layer after press was measured.

[Fourth Embodiment]

According to the first embodiment, the positive electrode slurry was coated on one side of the current collector by a coater while running a 20 μm thick aluminum foil current collector at a traveling speed of 16 m / min.

Subsequently, the positive electrode slurry was dried by the following drying step.

First, the total blowing air volume 40Nm3 / of the furnace temperature of 140 degreeC of a preheating process (1st drying zone), an upper nozzle (10% of opening ratio, D1: 15mm), and a lower nozzle (slit width: 5mm, D2: 10mm) min (circulating air volume 40Nm3 / min), furnace temperature 135 degreeC of a preheating process (2nd drying zone), an upper nozzle (10% of opening ratio, D1: 15mm), and a lower nozzle (slit width: 5mm, D2: 10mm) ) Was heated under the conditions of 50 Nm 3 / min of total blowing air flow rate (20 Nm 3 / min of circulating air volume and 30 Nm 3 / min of air introduced from the outside).

Subsequently, furnace temperature 135 degreeC of each zone of a constant evaporation process (3rd to 6th dry zone), an upper nozzle (30% of opening ratio, D1: 15mm), and a lower nozzle (slit width: 5mm, D2: Constant evaporation was performed on the conditions of the total blowing air volume of 200 mm <3> / min (10 mm) (circulating air volume of 25 Nm <3> / min, and air quantity 175 Nm <3> / min introduced from the outside).

Moreover, furnace temperature 140 degreeC of each zone of a reduction ratio evaporation process (7th dry zone and 8th dry zone), an upper nozzle (10% of opening ratio, D1: 15mm), and a lower nozzle (slit width: 5mm, D2: 10) Reduction rate evaporation was performed on condition of the total blowing air volume of 120 Nm <3> / min (circulating air volume of 105 Nm <3> / min, and air quantity 15Nm <3> / min of air taken in from outside).

As a result, the amount of evaporation NMP in the preheating step is 3% by weight (the amount of residual NMP is 97% by weight) and the amount of evaporation NMP in the constant rate evaporation step with respect to the amount of NMP (the amount of residual NMP is 100% by weight) carried into the drying furnace. Silver 94 weight% (residual NMP amount is 3 weight%) and the evaporation NMP amount in the reduction rate evaporation process were 2.97 weight% (residual NMP amount was 0.03 weight%).

In addition, when the rate reduction evaporation process was complete | finished, the NMP content which remains in the positive electrode layer was analyzed by gas chromatography, and it confirmed that it was 0.03 weight%.

Moreover, according to the 1st Example, the surface of the positive electrode was observed and the adhesive strength of the electrode active material layer after press was measured.

[Fifth Embodiment]

In the fourth embodiment, an infrared heating furnace device is incorporated in the preheating step, the furnace temperature of the preheating step (first drying zone) is 140 ° C., the upper nozzle (opening ratio 20%, D1: 50 mm) and the lower nozzle (slit width). : 5 mm, D2: 10 mm) total blowing air volume 25Nm3 / min (circulating air volume 25Nm3 / min), furnace temperature 135 ° C in the preheating process (second drying zone), upper nozzle (opening ratio 20%, D1: 50) The temperature was raised on the conditions of 50 Nm <3> / min of total blowing air volume of 50 Nm <3> / min (circulating air volume of 10Nm <3> / min, and 40 Nm <3> / min of air quantity introduced from the exterior) of a lower nozzle (slit width: 5 mm, D2: 10mm). . Other than this was carried out similarly to the 4th Example.

[Sixth Embodiment]

In the fourth embodiment, an infrared heating furnace device is incorporated in the constant evaporation process, so that the furnace temperature of each zone of the constant evaporation processes (third to sixth drying zones) is 135 ° C., and the upper nozzle (opening ratio 35%, D1). : 50 mm) and constant evaporation under the conditions of the total blowing air volume of 175 Nm3 / m (circulating air volume of 0 Nm3 / min and the amount of air introduced from the outside 175 Nm3 / min) of the lower nozzle (slit width: 5 mm, D2: 10 mm) Was performed. Other than this was carried out similarly to the 4th Example.

[Example 7]

In the fourth embodiment, an infrared heating furnace device is incorporated in the reduction rate heating zone so as to provide a furnace temperature of 140 ° C. and an upper nozzle (opening ratio of 20%, D1) in each zone of the reduction rate evaporation process (seventh drying zone and eighth drying zone). : 50 mm) and reduction rate evaporation on condition of total blowing air volume 70Nm3 / min (circulating airflow 55Nm3 / min and air volume 15Nm3 / min introduced from the outside) of the lower nozzle (slit width: 5mm, D2: 10mm) Was performed. Other than this was carried out similarly to the 4th Example.

[Eighth Embodiment]

In Example 4, an infrared heating apparatus was arrange | positioned in the place of 2.5 m from the position which exited the reduction rate heating zone, and further drying was performed on 130 degreeC conditions. Other than this was carried out similarly to the 4th Example.

[Example 9]

(Composition of Anode Slurry)

(Manufacture of negative electrode slurry)

A negative electrode slurry having the structure of Table 3 was prepared as follows. First, 6.5 parts by weight of PVDF was dissolved in 45 parts by weight of NMP to prepare a PVDF solution. Next, 51.5 parts by weight of the PVDF solution was added to 1.1 parts by weight of the conductivity-imparting agent and 100 parts by weight of the natural graphite powder, followed by kneading with a planetary mixer (manufactured by Asada Co., Ltd., PVM100). A weight part was added to make a negative electrode slurry (52 weight% of solid content concentration).

(Application and Drying of Anode Slurry)

The said negative electrode slurry was apply | coated to the single side | surface of an electrical power collector by the coater, running a 10-micrometer-thick rolled copper foil current collector at a traveling speed of 8 m / min.

Subsequently, the negative electrode slurry was dried by the following drying step.

First, furnace temperature 125 degreeC of each zone of a preheating process (1st drying zone and 2nd drying zone), an upper nozzle (10% of opening ratio, D1: 50mm), and a lower nozzle (slit width: 5mm, D2: 10mm) ), The temperature was raised under the condition of the total blowing air volume of 30 Nm 3 / min (the circulation air volume of 20 Nm 3 / min and the amount of air introduced from the outside 10 Nm 3 / min).

Subsequently, furnace temperature 115 degreeC of each zone of a constant evaporation process (3rd to 6th dry zone), an upper nozzle (30% of opening ratio, D1: 50mm), and a lower nozzle (slit width: 5mm, D2: Constant evaporation was performed on the conditions of the total blowing air volume of 60 mm <3> / m (10 mm) (circulating air volume of 12 Nm <3> / min, and 48 Nm <3> / min of air quantity introduced from the outside).

Moreover, furnace temperature 130 degreeC of each zone of a reduction ratio evaporation process (7th dry zone and 8th dry zone), an upper nozzle (10% of opening ratio, D1: 50mm), and a lower nozzle (slit width: 5mm, D2: 10) Reduction rate evaporation was performed on condition of the total blowing air volume of 70 Nm <3> / min (circulating air volume of 60 Nm <3> / min, and 10 Nm <3> / min of air amount taken in from outside) of total volume of air.

The amount of NMP evaporated in each step was measured by the NMP concentration sensor provided at the top of each step, and the NMP content remaining in the coating layer (negative electrode slurry coated on the current collector) passing through each step was calculated.

As a result, the amount of evaporation NMP in the preheating step is 4% by weight (the amount of residual NMP is 96% by weight) and the amount of evaporation NMP in the constant rate evaporation step with respect to the amount of NMP (residual NMP amount is 100% by weight) carried into the drying furnace. The amount of evaporation NMP in 95% by weight of silver (the amount of residual NMP was 1% by weight) and the reduction rate evaporation process was 0.98% by weight (the amount of residual NMP was 0.02% by weight).

Moreover, when NMP content which remained in the negative electrode layer when the reduction rate evaporation process was complete | finished was analyzed by gas chromatography, it was confirmed that it is 0.02 weight%.

Moreover, it applied and dried also on the back surface of the rolled copper foil collector on the conditions similar to the above, and formed the sheet-like electrode which has an electrode active material layer on both surfaces. A roller press was applied to the sheet-shaped electrode, compression molded, and cut to produce a negative electrode having a thickness of about 60 μm of the active material layer on one side. When the surface of the negative electrode was observed, no crack was observed.

In addition, the adhesive strength of the electrode active material layer after a press is 90 degree tensile test (tester: Seisakusho Co., Model Number: SV-52NA-20M, load cell maximum load: 200 N, tensile velocity: 100 mm / min, sample piece) : 15 mm x 80 mm).

[Tenth Embodiment]

According to the ninth example, the paint was applied to one side of a 10 μm rolled copper foil current collector.

Subsequently, the negative electrode slurry was dried by the following drying step.

First, the total blowing air volume 15Nm3 / of the furnace temperature of 125 degreeC of a preheating process (1st drying zone), an upper nozzle (10% of opening ratio, D1: 25mm), and a lower nozzle (slit width: 5mm, D2: 10mm) min (circulating air volume 15Nm3 / min), furnace temperature 115 degreeC of a preheating process (2nd drying zone), an upper nozzle (10% of opening ratio, D1: 50mm), and a lower nozzle (slit width: 5mm, D2: 10mm) ), The temperature was raised under the condition of 15 Nm 3 / min of total blowing air flow rate (5Nm 3 / min of circulation air flow rate and 10Nm 3 / min of air amount introduced from the outside).

Subsequently, furnace temperature 115 degreeC of each zone of a constant evaporation process (3rd to 6th dry zone), an upper nozzle (30% of opening ratio, D1: 25mm), and a lower nozzle (slit width: 5mm, D2: Constant evaporation was performed on the conditions of the total blowing air volume of 60 mm <3> / m (10 mm) (circulating air volume of 12 Nm <3> / min, and 48 Nm <3> / min of air quantity introduced from the outside).

Moreover, furnace temperature 130 degreeC of each zone of a reduction ratio evaporation process (7th dry zone and 8th dry zone), an upper nozzle (10% of opening ratio, D1: 25mm), and a lower nozzle (slit width: 5mm, D2: 10) Reduction rate evaporation was performed on condition of the total blowing air volume of 70 Nm <3> / min (circulating air volume of 60 Nm <3> / min, and 10 Nm <3> / min of air amount taken in from outside) of total volume of air.

As a result, the amount of evaporation NMP in the preheating step is 4% by weight (the amount of residual NMP is 96% by weight) and the amount of evaporation NMP in the constant rate evaporation step with respect to the amount of NMP (residual NMP amount is 100% by weight) carried into the drying furnace. The amount of evaporation NMP in 95% by weight of silver (the amount of residual NMP was 1% by weight) and the reduction rate evaporation process was 0.97% by weight (the amount of residual NMP was 0.03% by weight).

Moreover, when NMP content which remained in the negative electrode layer when the reduction rate evaporation process was complete | finished was analyzed by gas chromatography, it was confirmed that it is 0.03 weight%.

In addition, according to the first embodiment, the surface of the negative electrode was observed, and the adhesion strength of the electrode active material layer after pressing was measured.

[Eleventh Embodiment]

According to the tenth embodiment, the negative electrode slurry was coated on one side of the current collector by a coater while running a 10 μm thick copper foil current collector at a traveling speed of 12 m / min.

Subsequently, the negative electrode slurry was dried by the following drying step.

First, the total blowing air volume of 20 Nm3 / of the furnace temperature of 125 degreeC of a preheating process (1st drying zone), an upper nozzle (10% of opening ratio, D1: 25mm), and a lower nozzle (slit width: 5mm, D2: 10mm) min (circulating air volume 20Nm3 / min), furnace temperature 120 degreeC of a preheating process (2nd drying zone), an upper nozzle (10% of opening ratio, D1: 25mm), and a lower nozzle (slit width: 5mm, D2: 10mm) ) Was heated on the conditions of 20 Nm <3> / min of total blowing air volume (circulating air volume 10Nm <3> / min, and 10Nm <3> / min of air quantity introduced from the outside).

Subsequently, furnace temperature 120 degreeC of each zone of a constant evaporation process (3rd to 6th dry zone), an upper nozzle (30% of opening ratio, D1: 15mm), and a lower nozzle (slit width: 5mm, D2: Constant evaporation was performed on the conditions of the total blowing air volume of 80 mm <3> / m (10 mm) (circulating air volume of 15 Nm <3> / min, and the quantity of air introduced from the exterior 65 Nm <3> / min).

Moreover, furnace temperature 130 degreeC of each zone of a reduction ratio evaporation process (7th dry zone and 8th dry zone), an upper nozzle (10% of opening ratio, D1: 15mm), and a lower nozzle (slit width: 5mm, D2: 10) Reduction rate evaporation was performed on condition of the total blowing air volume of 70 Nm <3> / min (circulating air volume of 60 Nm <3> / min, and 10 Nm <3> / min of air amount taken in from outside) of total volume of air.

As a result, the amount of evaporation NMP in the preheating step is 4% by weight (the amount of residual NMP is 96% by weight) and the amount of evaporation NMP in the constant rate evaporation step with respect to the amount of NMP (residual NMP amount is 100% by weight) carried into the drying furnace. Silver 94 weight% (remaining NMP amount is 2 weight%), and evaporation NMP amount in the reduction rate evaporation process was 1.97 weight% (residual NMP amount is 0.03 weight%).

Moreover, when NMP content which remained in the negative electrode electrode layer at the time of completion | finish of a rate reduction evaporation process was analyzed by gas chromatography, it was confirmed that it is 0.03 weight%.

In addition, according to the first embodiment, the surface of the negative electrode was observed, and the adhesion strength of the electrode active material layer after pressing was measured.

[Twelfth Embodiment]

According to the tenth embodiment, the negative electrode slurry was coated on one side of the current collector by a coater while running the rolled copper foil current collector having a thickness of 10 μm at a traveling speed of 16 m / min.

Subsequently, the negative electrode slurry was dried by the following drying step.

First, the total blowing air volume 25Nm3 / of the furnace temperature of 130 degreeC of a preheating process (1st drying zone), an upper nozzle (10% of opening ratio, D1: 15mm), and a lower nozzle (slit width: 5mm, D2: 10mm) min (circulating air volume 25Nm3 / min), furnace temperature 130 degreeC of a preheating process (2nd drying zone), an upper nozzle (10% of opening ratio, D1: 15mm), and a lower nozzle (slit width: 5mm, D2: 10mm) The temperature was raised under the condition of 25 Nm 3 / min of total blowing air volume (circulating air volume 15Nm 3 / min and 10 Nm 3 / min of air introduced from the outside).

Subsequently, furnace temperature 125 degreeC of each zone of a constant evaporation process (3rd to 6th dry zone), an upper nozzle (30% of opening ratio, D1: 15mm), and a lower nozzle (slit width: 5mm, D2: Constant evaporation was performed on the conditions of 100 Nm <3> of total blowing air volume of 10 mm) (circulating air volume of 10 Nm <3> / min, and 90 Nm <3> / min of air quantity introduced from the outside).

In addition, furnace temperature 135 degreeC of each zone of a reduction ratio evaporation process (7th dry zone and 8th dry zone), an upper nozzle (10% of opening ratio, D1: 15mm), and a lower nozzle (slit width: 5mm, D2: 10) Reduction rate evaporation was performed on condition of 100 Nm <3> of total blow-out air volume (mm) (circulating air volume 80Nm <3> / min, and 20 Nm <3> / min of air quantity introduced from the outside).

As a result, the amount of evaporation NMP in the preheating step is 3% by weight (the amount of residual NMP is 97% by weight) and the amount of evaporation NMP in the constant rate evaporation step with respect to the amount of NMP (the amount of residual NMP is 100% by weight) carried into the drying furnace. Silver 94 weight% (residual NMP amount is 3 weight%) and the evaporation NMP amount in the reduction rate evaporation process were 2.97 weight% (residual NMP amount was 0.03 weight%).

Moreover, when NMP content which remained in the negative electrode layer when the reduction rate evaporation process was complete | finished was analyzed by gas chromatography, it was confirmed that it is 0.03 weight%.

In addition, according to the first embodiment, the surface of the negative electrode was observed, and the adhesion strength of the electrode active material layer after pressing was measured.

[Example 13]

In the twelfth embodiment, an infrared heating furnace device is incorporated in the preheating step, and the furnace temperature of the preheating step (first drying zone) is 125 ° C., the upper nozzle (opening ratio 20%, D1: 50 mm) and the lower nozzle (slit width). : 5 mm, D2: 10 mm) total blowing air volume 15 Nm 3 / min (circulating air volume 15 Nm 3 / min), furnace temperature 125 ° C., upper nozzle (opening ratio 20%, D1: 50) of preheating step (second drying zone) It heated up on the conditions of the total blowing air volume of 15 Nm <3> / min (circulating air volume of 5 Nm <3> / min, and the amount of air introduced from the outside 10Nm <3> / min) of the lower nozzle (slit width: 5 mm, D2: 10 mm). . Other than this was carried out similarly to the twelfth example.

[Example 14]

In the twelfth embodiment, an infrared heating apparatus is incorporated in the constant evaporation process, so that the furnace temperature of each zone of the constant evaporation processes (third to sixth dry zones) is 115 ° C. and the upper nozzle (opening ratio 40%, D1). : 50 mm) and constant evaporation was performed on condition of the total blowing air volume 90Nm <3> / m (air amount 90Nm <3> / min introduced from the outside) of a lower nozzle (slit width: 5mm, D2: 10mm).

Other than this was carried out similarly to the twelfth example.

[Example 15]

In the twelfth embodiment, an infrared heating furnace device is incorporated in the reduction rate evaporation step, so that the furnace temperature 130 ° C. and the upper nozzle (opening ratio 20%, D1) of each zone of the reduction rate evaporation step (seventh drying zone and eighth drying zone) are included. : 50 mm) and the conditions of 70 Nm <3> / min of blow-off air volume from all the nozzles of a lower nozzle (slit width: 5 mm, D2: 10mm) (circulating air volume of 60 Nm <3> / min, and 10 Nm <3> / min of air quantity introduced from the outside) Reduction rate evaporation was performed. Other than this was carried out similarly to the twelfth example.

[Example 16]

In Example 12, an infrared heating apparatus was arrange | positioned in the place of 2.5 m from the position which exited the reduction rate heating zone, and further drying was performed on 130 degreeC conditions. Other than this was carried out similarly to the twelfth example.

[Example 17]

According to the first embodiment, the positive electrode slurry was coated on one side of the current collector by a coater while running a 20 μm thick aluminum foil current collector at a traveling speed of 8 m / min. Subsequently, there are four blocks of constant evaporation in Fig. 1 (total furnace length 20 m in an eight-fuel furnace with one block of 2.5 m) and Fig. 4 (distance D1 from the upper nozzle to the foil: 10 to 150 mm, Using the drying furnace shown to distance (D2) from a lower nozzle to foil (10-75 mm), the positive electrode slurry was dried by the following drying processes.

First, furnace temperature 135 degreeC of each zone of a preheating process (1st drying zone and 2nd drying zone), an upper nozzle (10% of opening ratio, D1: 50mm), and a lower nozzle (slit width: 5mm, D2: 10mm) ) Was heated on the conditions of 50 Nm <3> / min of total blowing air volume (43Nm <3> / min of circulating air volume, and 7Nm <3> / min of air quantity introduced from the outside).

Subsequently, furnace temperature 125 degreeC of each zone of the constant evaporation process 1 (3rd dry zone and 4th dry zone), an upper nozzle (30% of opening ratio, D1: 25mm), and a lower nozzle (slit width: 5mm, D2) Constant evaporation was performed on the conditions of the total blowing air volume of 29 Nm <3> / m (circle air volume of 3 Nm <3> / min, and 26 Nm <3> / min of air quantity taken in from outside) of 10 mm).

Subsequently, furnace temperature 130 degreeC of each zone of the constant evaporation process 2 (5th dry zone and 6th dry zone), an upper nozzle (20% of opening ratio, D1: 25mm), and a lower nozzle (slit width: 5mm, D2) Constant evaporation was performed on the conditions of the total blowing air volume of 71 Nm <3> / m (circle air volume of 7 Nm <3> / min, and the air amount 64Nm <3> / min introduced from the outside) of (10 mm).

Moreover, furnace temperature 140 degreeC of each zone of a reduction ratio evaporation process (7th dry zone and 8th dry zone), an upper nozzle (10% of opening ratio, D1: 100mm), and a lower nozzle (slit width: 5mm, D2: 10) Reduction rate evaporation was performed on the conditions of 70 Nm <3> / min of total blow-out air volume (mmN) (circulating air volume 67Nm <3> / min, and 3Nm <3> / min of air quantity introduced from the outside).

The amount of NMP discharged (evaporated) from each step is measured by an NMP concentration sensor provided at the top of each step, and the remaining solvent content of the coating layer (positive electrode slurry coated on the current collector) passing through each step is measured. Calculated.

As a result, the amount of evaporation NMP in the preheating step is 7% by weight (the amount of residual NMP is 93% by weight) and the evaporation NMP in the constant rate evaporation step 1 to the amount of NMP (the amount of residual NMP is 100% by weight) carried into the drying furnace. The amount is 27% by weight (the amount of residual NMP is 66% by weight), the amount of evaporation NMP in the constant rate evaporation step 2 is 65% by weight (the amount of residual NMP is 1% by weight), and the amount of evaporation NMP in the reduction rate evaporation step is 0.97% by weight. (The residual NMP amount was 0.03 wt%).

Moreover, when NMP content which remained in the positive electrode layer when the reduction rate evaporation process was complete | finished was analyzed by gas chromatography, it was confirmed that it is 0.03 weight%.

Moreover, according to the 1st Example, the surface of the positive electrode was observed and the adhesive strength of the electrode active material layer after press was measured.

[Example 18]

According to the first embodiment, the positive electrode slurry was coated on one side of the current collector by a coater while running a 20 μm thick aluminum foil current collector at a traveling speed of 16 m / min.

Subsequently, the positive electrode slurry was dried by the following drying step.

First, the total blowing air volume 40Nm3 / of the furnace temperature of 140 degreeC of a preheating process (1st drying zone), an upper nozzle (10% of opening ratio, D1: 15mm), and a lower nozzle (slit width: 5mm, D2: 10mm) min (circulating air volume 40Nm3 / min), furnace temperature 135 degreeC of a preheating process (2nd drying zone), an upper nozzle (10% of opening ratio, D1: 15mm), and a lower nozzle (slit width: 5mm, D2: 10mm) ) Was heated under the conditions of 50 Nm 3 / min of total blowing air flow rate (20 Nm 3 / min of circulating air volume and 30 Nm 3 / min of air introduced from the outside).

Subsequently, furnace temperature 130 degreeC of each zone of the constant evaporation process 1 (3rd dry zone and 4th dry zone), an upper nozzle (35% of opening ratio, D1: 25mm), and a lower nozzle (slit width: 5mm, D2) Constant evaporation was performed on conditions of the total blowing air volume of 58 Nm <3> / m (circle air volume of 6 Nm <3> / min, and air quantity 52Nm <3> / min introduced from the outside) of (10 mm).

Subsequently, furnace temperature 135 degreeC of each zone of the constant evaporation process 2 (5th dry zone and 6th dry zone), an upper nozzle (30% of opening ratio, D1: 25mm), and a lower nozzle (slit width: 5mm, D2) Constant evaporation was performed on conditions of 142 Nm <3> / m (circulating air volume 19Nm <3> / min and 123 Nm <3> / min of air quantity introduced from the outside) blow-out air volume from all the nozzles of 10 mm).

Moreover, furnace temperature 140 degreeC of each zone of a reduction ratio evaporation process (7th dry zone and 8th dry zone), an upper nozzle (10% of opening ratio, D1: 15mm), and a lower nozzle (slit width: 5mm, D2: 10) Reduction rate evaporation was performed on condition of 120 Nm <3> of blow-off air volume from all the nozzles of mm) (circulating air volume 105Nm <3> / min, and 15 Nm <3> / min of air quantity introduced from the outside).

As a result, the amount of evaporation NMP in the preheating step is 3% by weight (the amount of residual NMP is 97% by weight) and the evaporation NMP in the constant rate evaporation step 1 to the amount of NMP (residual NMP amount is 100% by weight) carried into the drying furnace. The amount is 27% by weight (the amount of residual NMP is 66% by weight), the amount of evaporation NMP in the constant rate evaporation step 2 is 65% by weight (the amount of residual NMP is 1% by weight), and the amount of evaporation NMP in the reduction rate evaporation step is 2.97% by weight. (The residual NMP amount was 0.03 wt%).

Moreover, when NMP content which remained in the positive electrode layer when the reduction rate evaporation process was complete | finished was analyzed by gas chromatography, it was confirmed that it is 0.03 weight%.

Moreover, according to the 1st Example, the surface of the positive electrode was observed and the adhesive strength of the electrode active material layer after press was measured.

[First Comparative Example]

According to the first embodiment, the coating material was applied to a single side of the current collector by a die coater while running a 20 μm thick aluminum foil current collector at a traveling speed of 8 m / min.

Subsequently, the positive electrode slurry was dried by the following drying step.

First, all the jets of furnace temperature 140 degreeC of each zone of preheating process (1-2), an upper nozzle (slit width: 5 mm, D1: 50 mm), and a lower nozzle (slit width: 5 mm, D2: 10 mm) It heated up on the conditions of 100 Nm <3> / min of air volume (50 Nm <3> / min of circulation air volume, and 50 Nm <3> / min of air quantity introduced from the exterior).

Subsequently, furnace temperature 135 degreeC of each zone of a constant evaporation process (3rd to 6th dry zone), an upper nozzle (slit width: 5 mm, D1: 25 mm), and a lower nozzle (slit width: 5 mm, Constant evaporation was performed on condition of 200 Nm <3> of blow-off air volume from all the nozzles of D2: 10mm) (circulating air volume 25Nm <3> / min, and 175 Nm <3> / min of air quantity introduced from the outside).

Moreover, furnace temperature 140 degreeC of each zone of a reduction ratio evaporation process (7th dry zone and 8th dry zone), an upper nozzle (slit width: 5 mm, D1: 25 mm), and a lower nozzle (slit width: 5 mm, D2) Reduction rate evaporation was performed on condition of 120 Nm <3> of blow-off air volume from all the nozzles of 10 mm) (circulating air volume 105Nm <3> / min, and 15 Nm <3> / min of air quantity introduced from the outside).

As a result, the amount of evaporation NMP in the preheating step is 21% by weight (the amount of residual NMP is 79% by weight) and the amount of evaporation NMP in the constant rate evaporation step with respect to the amount of NMP (the amount of residual NMP is 100% by weight) carried into the drying furnace. 78 weight% of silver (the amount of residual NMP was 1 weight%) and the amount of evaporation NMP in the reduction rate evaporation process were 0.97 weight% (the amount of residual NMP was 0.03 weight%).

Moreover, when NMP content which remained in the positive electrode layer when the reduction rate evaporation process was complete | finished was analyzed by gas chromatography, it was confirmed that it is 0.03 weight%.

Moreover, according to the 1st Example, the surface of the positive electrode was observed and the adhesive strength of the electrode active material layer after press was measured.

Second Comparative Example

According to the tenth example, the coating material was applied to a single side of the current collector by a die coater while running a rolled copper foil current collector having a thickness of 10 μm at a traveling speed of 8 m / min.

Subsequently, the negative electrode slurry was dried by the following drying step.

First, the total blowing air volume of the furnace temperature 140 ° C. of the preheating step (1 to 2), the upper nozzle (5% opening ratio, D1: 25 mm) and the lower nozzle (slit width: 5 mm, D2: 10 mm) 50 Nm 3 / min It heated up on conditions of (circulating air volume 30Nm <3> / min and air quantity 20Nm <3> / min introduced from the outside).

Subsequently, furnace temperature 130 degreeC of each zone of a constant evaporation process (3rd to 6th dry zone), an upper nozzle (5% of opening ratio, D1: 25mm), and a lower nozzle (slit width: 5mm, D2: Constant evaporation was performed on conditions of 100 Nm <3> of blow-off air volume from all the nozzles of 10 mm) (circulating air volume 10Nm <3> / min, and 90 Nm <3> / min of air quantity introduced from the outside).

Moreover, furnace temperature 135 degreeC of each zone of a reduction ratio evaporation process (7th dry zone and 8th dry zone), an upper nozzle (5% of opening ratio, D1: 25mm), and a lower nozzle (slit width: 5mm, D2: 10) Reduction rate evaporation was performed on condition of 100 Nm <3> of blow-off air volume from all the nozzles of mm) (circulating air volume 80Nm <3> / min, and 20 Nm <3> / min of air quantity introduced from the outside).

As a result, the amount of evaporation NMP in the preheating step is 10% by weight (the amount of residual NMP is 90% by weight), and the amount of evaporation NMP in the constant rate evaporation step, relative to the amount of NMP (residual NMP amount is 100% by weight) carried into the drying furnace. The 89% by weight of silver (the amount of residual NMP was 1% by weight) and the amount of evaporation NMP in the reduction rate evaporation step were 0.97% by weight (the amount of residual NMP was 0.03% by weight).

Moreover, when NMP content which remained in the positive electrode layer when the reduction rate evaporation process was complete | finished was analyzed by gas chromatography, it was confirmed that it is 0.03 weight%.

In addition, according to the tenth example, the surface of the negative electrode was observed, and the adhesion strength of the electrode active material layer after pressing was measured.

Table 4 shows the ratio of the integral strength of the binder in the vicinity of the current collector to the adhesion strength and the integral strength of all the binders in the first to eighth, seventeenth, eighteenth examples, and the first comparative example. have. From Table 4, by using the electrode manufacturing apparatus concerning this invention, the ratio of the integral intensity of the binder in the vicinity of an electrical power collector with respect to the integral strength of all the binders has 30% or more, and also the electrode with high adhesive strength can be manufactured. Could.

In addition, Table 5 shows the average D / G value in the vicinity of the electrode layer surface layer with respect to the adhesive strength and average D / G value Rb in the electrode layer center part in 9th-16th Example and the 2nd comparative example. The ratio (Rs / Rb) of (Rs) is shown. From Table 5, by using the electrode manufacturing apparatus concerning this invention, Rs / Rb was 2 or less and the electrode with high adhesive strength was able to be manufactured.

1: electrode manufacturing apparatus
30: drying furnace
33: perforated plate nozzle
55: infrared heating element
100, 200: electrode
101, 201: current collector
102, 202: coating layer
103,203: electrode layer
110, 210: electrode slurry
111, 211: active material
112, 212: binder
113, 213: conductivity giving agent
114, 214: solvent
A01: around the current collector
A02: Near the electrode layer surface layer
A03: center of electrode layer
S04: preheating process
S05: constant evaporation process
S06: Reduction Rate Evaporation Process

Claims (11)

It is an electrode in which an electrode layer overlaps a current collector,
The electrode of the area | region in which the electrical power collector of an electrode layer overlaps is higher in the component concentration of the binder contained in the said electrode layer than the area | region of the surface layer side opposite to the side where the said electrical power collector overlaps. The said all binder is measured by Raman spectroscopy in the vicinity of an electrical power collector which is an area | region from the side where the electrical power collector of the said electrode layers overlaps to 1/4 when the thickness of the whole of the said electrode layer is set to 1, The electrode which has 20 to 40% of the integral intensity which is an integrated value of the peak intensity shown in the specific wavelength band at the time of making. The electrode according to claim 2, wherein the vicinity of the current collector is higher in integral strength of the binder than the vicinity of the electrode layer surface layer, which is an area from the surface layer side to a quarter opposite to the side where the current collector of the electrode layer overlaps. The surface layer in the vicinity of the electrode layer surface layer according to any one of claims 1 to 3, wherein when the thickness of the entire electrode layer is 1, the electrode layer surface layer vicinity is an area from the surface layer side in contact with air of the electrode layer to 1/4. An electrode having a region having a higher concentration of the conductivity-imparting agent than an electrode layer center portion, which is a region from 1/4 to 1 with respect to the side. 5. The average D / G value according to claim 4, wherein the average D / G value, which is the intensity ratio of the peak of the D band to the G band of carbon measured by Raman spectroscopy, is Rs in the vicinity of the electrode layer surface layer and Rb in the center of the electrode layer. The electrode which satisfies the relationship of / Rb. A coating layer formed by applying an electrode slurry containing an active material, a binder, a conductivity-imparting agent, and a solvent to a current collector is dried in a drying furnace to produce an electrode in which an electrode layer overlaps the current collector.
A preheating step of preheating the electrode slurry,
Constant rate evaporation process of constant drying rate of electrode slurry,
A method for producing an electrode, wherein the drying rate of the electrode slurry has a decreasing rate evaporation process that gradually decreases depending on the decrease in the solvent content of the electrode slurry. The amount of solvent remaining in the electrode slurry at the end of each step in the preheating step, the constant rate evaporation step and the reduction rate evaporation step is 100 to 90% by weight, 95 to 1% by weight, respectively. The electrode manufacturing method in 5 to 0.01% of range. The said constant evaporation process has a 1st constant evaporation process and a 2nd constant evaporation process, The amount of solvent which remain | survives in the electrode slurry when each process is complete is 95-65 weight%, 65-, respectively. The electrode manufacturing method in the range of 1 weight%. The electrode production method according to any one of claims 6 to 8, wherein the amount of solvent remaining in the electrode slurry after the reduction rate evaporation step is completed is 0.1% by weight or less. The coating layer formed by apply | coating the electrode slurry containing an active material, a binder, electroconductivity imparting agent, and a solvent to a collector is dried in a drying furnace, and the electrode which overlaps an electrode layer with the said collector is manufactured. It is an electrode manufacturing apparatus used for the electrode manufacturing method of any one of 8,
The electrode manufacturing apparatus which has a porous plate nozzle with many holes opened in the exit of the hot air for heat-drying the surface in which the coating layer of the said electrode slurry was formed by hot air, and the said porous plate nozzle is 10% or more of aperture ratio. The electrode manufacturing apparatus of Claim 10 which has an infrared heating body for heat-drying the surface in which the application layer of the said electrode slurry was formed.

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