JP2006309958A - Slurry for forming lithium ion battery electrode, manufacturing method of the same, and lithium ion battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a slurry for forming a lithium ion battery electrode improved in dispersibility of conductive assistant in electrode activator, realizing high output of the lithium ion battery by adding small amount of conductive assistant, and to provide a manufacturing method of the same, and the lithium ion battery. <P>SOLUTION: The slurry for forming a lithium ion battery electrode contains electrode activator, conductive assistant, binder, and polarized solvent. Average grain size when the conductive assistant is dispersed is 500 nm or less. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a slurry for forming an electrode of a lithium ion battery, a method for producing the same, and a lithium ion battery. The present invention relates to a slurry, a manufacturing method thereof, and a lithium ion battery.

In recent years, lithium ion batteries, for example, non-aqueous electrolyte secondary batteries such as lithium ion batteries have been proposed and put into practical use as small, light, and high capacity batteries. This lithium ion battery is composed of a positive electrode and a negative electrode having a property capable of reversibly removing and inserting lithium ions, and a non-aqueous electrolyte.
A carbon-based material is generally used for the negative electrode of the lithium ion battery. On the other hand, the positive electrode is composed of a Li-containing metal oxide having a performance capable of reversibly removing and inserting lithium ions, which is referred to as a positive electrode active material, a conductive additive and a binder, and a slurry in which these are dispersed and dissolved is used as a current collector. A positive electrode is formed by applying to the surface of a metal foil called.

As the positive electrode active material of this lithium ion battery, lithium cobaltate (LiCoO ₂ ) is usually used, but in addition, lithium nickelate (LiNiO ₂ ), lithium manganate (LiMnO ₂ ), lithium iron phosphate Lithium (Li) compounds such as (LiFePO ₄ ) have been proposed.
Lithium ion batteries using these positive electrode active materials are used as power sources for portable electronic devices such as mobile phones and notebook personal computers, but in recent years, high-output power sources for electric vehicles, hybrid vehicles, electric tools, etc. Is also being considered.

Conventionally, nickel hydride batteries having high output performance have been used as these high output power sources, and lithium ion batteries have not been put into practical use. This is because the output performance of the lithium ion battery is lower than that of the nickel metal hydride battery.
One of the reasons why the output performance of the lithium ion battery is inferior is that the electronic conductivity and ionic conductivity of the positive electrode active material are low. Therefore, as a method for improving the electronic conductivity of the electrode active material, A method of adding a conductive additive to the electrode active material is used (see Non-Patent Document 1). As the conductive assistant, carbon-based conductive materials such as acetylene black, carbon black, ketjen black, natural graphite, and artificial graphite are generally used.
Yoshiharu Matsuda, Zenichiro Takehara et al., “Battery Handbook 3rd Edition”, Maruzen Co., Ltd., issued February 20, 2001, p. 267

However, in the conventional method of adding a conductive aid to an electrode active material, a mixer such as a ball mill or a stirring blade type mixer has been used for mixing the electrode active material and the conductive aid. In these mixers, There is a problem that the output performance of the battery cannot be sufficiently exhibited because the conductive auxiliary agent is not sufficiently dispersed and the conductivity of the electrode active material is insufficiently improved.
In addition, it is ideal that the conductive auxiliary agent exhibits an effect in as small an amount as possible, but if the conductive auxiliary agent is not sufficiently dispersed, it must be used in a large amount to obtain the desired output performance. Therefore, there has been a problem that the discharge capacity of the battery has to be low.

  The present invention has been made to solve the above-described problems, and improves the dispersibility of the conductive auxiliary agent in the electrode active material, and increases the output of the lithium ion battery with a smaller additive amount of the conductive auxiliary agent. It is an object to provide a slurry for forming an electrode of a lithium ion battery that can be realized, a method for manufacturing the same, and a lithium ion battery.

  As a result of intensive studies to solve the above problems, the present inventors have found that, in order to increase the output of a lithium ion battery, an electrode active material that is charged and discharged by transfer of lithium ions and electrons, a conductive auxiliary agent, It is effective to increase the number of interfaces (three-phase interface) of the electrolytic solution. To that end, it has been found that it is effective to finely disperse the conductive assistant, and the conductive assistant is finely dispersed. In order to disperse, it has been found that it is effective to use a dispersion improver. Furthermore, when the electrode active material, the conductive assistant, the binder and the polar solvent are stirred and dispersed together with the medium particles to form a slurry, The inventors found that it is effective to limit the number of medium particles, and completed the present invention.

  That is, the slurry for forming an electrode of a lithium ion battery of the present invention is a slurry for forming an electrode of a lithium ion battery containing an electrode active material, a conductive assistant, a binder and a polar solvent, and the conductive assistant is dispersed in the slurry. In this case, the average particle size is 500 nm or less.

In the slurry for electrodes of the lithium ion battery of the present invention, it is preferable to further add a dispersion improver.
The dispersion improver is preferably one selected from the group consisting of an amino group-containing organic acid, an amino group-containing organic acid salt, an imino group-containing organic acid, and an imino group-containing organic acid salt.
The dispersion improver preferably has an amine value of 15 or more.

  The method for producing a slurry for an electrode of a lithium ion battery according to the present invention is a method for producing a slurry for an electrode of a lithium ion battery according to the present invention, wherein the electrode active material, the conductive additive, the binder and the polar solvent are mixed into a medium particle. When the slurry is stirred and dispersed together to form a slurry, the number of the medium particles in 1 ml of the slurry is 3500 or more.

  The lithium ion battery of the present invention comprises a positive electrode using the electrode slurry of the lithium ion battery of the present invention.

  According to the slurry for forming an electrode of the lithium ion battery of the present invention, since the average particle diameter when the conductive additive is dispersed is 500 nm or less, the conductive additive can be sufficiently uniformly dispersed, The conductivity can be increased, and the discharge capacity of the battery can be increased. Therefore, the dispersibility of the conductive additive in the electrode active material can be improved, and high output of the lithium ion battery can be realized with a smaller amount of conductive additive added.

  According to the method for producing a slurry for forming an electrode for a lithium ion battery of the present invention, when the electrode active material, the conductive additive, the binder and the polar solvent are stirred and dispersed together with the medium particles to form a slurry, Since the number of particles in 1 ml of the slurry is 3500 or more, the mixing and uniform dispersibility of the electrode active material, the conductive assistant, the binder and the polar solvent can be improved by the flow of the medium particles. Therefore, it is possible to easily obtain a slurry for forming an electrode of a lithium ion battery in which the conductive additive is sufficiently uniformly dispersed in the slurry.

  According to the lithium ion battery of the present invention, since the positive electrode using the slurry for the electrode of the lithium ion battery of the present invention is provided, the charge / discharge capacity (particularly, discharge capacity) of the positive electrode can be improved, The charge / discharge cycle can be stabilized and the output can be increased. Therefore, a high output lithium ion battery can be provided.

A slurry for forming an electrode of a lithium ion battery according to the present invention, a manufacturing method thereof, and the best mode of the lithium ion battery will be described.
The slurry for forming an electrode of a lithium ion battery of the present invention is a slurry for forming an electrode of a lithium ion battery containing an electrode active material, a conductive assistant, a binder and a polar solvent, and when the conductive assistant is dispersed. The average particle size (dispersed particle size) is 500 nm or less.

  Here, the average particle diameter is a number average particle diameter measured by various particle size distribution measuring apparatuses using a transmission method or a scattering method, and specifically, an optical measurement method such as a laser diffraction scattering method. Or an average particle diameter measured by an image analysis method of an electron microscope image.

The electrode active material may be any Li-containing metal oxide capable of reversibly removing and inserting lithium ions. For example, lithium iron phosphate (LiFePO ₄ ), lithium cobaltate (LiCoO ₂ ), nickel acid Lithium (LiNiO ₂ ), lithium manganate (LiMnO ₂ ) and the like are preferably used.

The conductive auxiliary agent is used to increase the output of the lithium ion battery, and a carbon-based conductive auxiliary agent is preferably used. Examples of the carbon-based conductive auxiliary agent include acetylene black, carbon black, and ketjen. Examples thereof include black, natural graphite, and artificial graphite.
When the conductive assistant is mixed with the electrode active material, it is necessary to disperse it in an average particle size of 500 nm or less, more preferably 300 nm or less.

  The primary particle diameter of the carbon-based conductive aid is as small as several tens of nanometers. However, since the cohesive property is strong and it is difficult to disperse, the dispersed particle diameter is usually as large as several micrometers. With such coarse dispersed particles, a sufficient number of three-phase interfaces cannot be formed in the electrode, and therefore the output of the lithium ion battery cannot be increased. Therefore, by setting the dispersed particle size of the conductive auxiliary agent to 500 nm or less, more preferably 300 nm or less, a sufficient three-phase interface is formed in the electrode and charging / discharging can be performed at high speed to obtain a high-power lithium ion battery. It becomes possible.

  Here, the reason why the dispersed particle size of the conductive auxiliary agent is 500 nm or less is that when the dispersed particle size exceeds 500 nm, a large amount of conductive auxiliary agent is used to form a sufficient number of three-phase interfaces on the surface of the electrode active material. As a result, the ratio of the electrode active material decreases, and the battery capacity decreases. Although there is no restriction | limiting in particular in the method of disperse | distributing a conductive support agent to 500 nm or less, Since it is strong in the general dispersion method, it is difficult.

  In the present invention, an amino group-containing organic acid, an amino group-containing organic acid salt, an imino group-containing organic acid, and an imino group-containing organic acid salt are used as a dispersion improver in order to set the dispersed particle size of the conductive assistant to 500 nm or less. When one type selected from the group is used, and as a dispersion method, a medium stirring type dispersing device is used to stir and disperse the electrode active material, conductive additive, binder and polar solvent together with the medium particles to form a slurry. In addition, the number of medium particles in 1 ml of slurry is set to 3500 or more.

  These amino group-containing organic acids, amino group-containing organic acid salts, imino group-containing organic acids, imino group-containing organic acid salts include aliphatic amines such as stearylamine acetate and dodecylethanolamine hydrochloride, or salts thereof, or Its condensate, stearyl trityl ammonium chloride, lauryl trimethyl ammonium chloride, distearyl dimethyl ammonium chloride, myristyl dimethyl benzyl ammonium chloride, lauryl pyridium bromide, 2-stearyl-1- (2-hydroxyethyl) -methylimidazolium chloride, etc. A quaternary ammonium salt is mentioned.

  In addition, ethylene oxide adducts of aliphatic amines such as polyoxyethylene laurylamine and polyoxystyrene stearylamine, alkylimidazolium betaines such as 2-stearyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine, Examples thereof also include alkyldiamine ethyl glycine hydrochloride such as lauryl diaminoethyl glycine hydrochloride, aminocarbomonic acids such as sodium β-coconut alkylaminopropionate, and N-alkyl betaines such as stearyldimethylaminoacetic acid betaine.

These amino group-containing organic acids, amino group-containing organic acid salts, imino group-containing organic acids, and imino group-containing organic acid salts preferably have an amine value of 15 or more. When the amine value is less than 15, in order to disperse the conductive assistant to 500 nm or less, a large amount of addition is required, or dispersion for a long time is required. It becomes impossible.
Here, the amine value indicates the total amount of 1, 2, and tertiary amines, and is represented by the number of mg of potassium hydroxide (KOH) equivalent to hydrochloric acid required to neutralize a 1 g sample.

  As the binder, organic binders such as polyvinylidene fluoride (PVdF), polytetrafluoroethylene (PTFE), ethylene-propylene-diene copolymer (EPDM), styrene-butadiene rubber (SBR), carboxymethylcellulose (CMC) and the like are suitable. Used for.

  Examples of the polar solvent include organic solvents that can dissolve and disperse the electrode active material, the conductive additive, and the binder, such as N-methylpyrrolidone, dimethylformamide, dimethylacetamide, trimethyl phosphate, methyl ethyl ketone, and tetrahydrofuran.

  When the slurry for electrode formation of the lithium ion battery of the present invention is prepared, when the electrode active material, the conductive additive, the binder and the polar solvent are put together with the medium particles into the container of the medium stirring type dispersing apparatus, The amounts of the electrode active material, the conductive additive, the binder, the polar solvent, and the medium particles are adjusted so that the number in 1 ml of the slurry is 3500 or more, and then stirred and dispersed.

  Usually, in order to prepare a slurry for electrode formation, an electrode active material, a conductive aid, a binder and a polar solvent are mixed using a ball mill, a stirring type mixer or the like. In this method, the electrode active material and the conductive aid are mixed. Large shear stress is not applied to the agent, and dispersion is not sufficient. Therefore, in the present invention, a medium stirring type dispersing device often used as a pigment dispersing device is used for dispersing the conductive auxiliary agent.

  This medium agitating type dispersing apparatus is composed of an electrode active material, a conductive additive, a binder and a polar solvent (these are collectively referred to as a material to be dispersed) and a large number of medium particles placed in a container. By stirring at high speed, the medium particles flow at high speed, and when the medium particles collide with each other, the electrode active material and the conductive auxiliary agent are trapped between the medium particles, and are dispersed by receiving the impact and elastic action due to the collision. To do. Examples of the medium stirring type dispersing device include a sand mill, a paint shaker, an attritor, a planetary ball mill, and a vibrating ball mill. Among these, a sand mill capable of stirring medium particles at high speed is preferable.

（ただし、Ｖｍは媒体粒子の見掛けの体積（ｃｍ^３）、Ｄｍは媒体粒子の直径（ｃｍ）、Ｖｓは被分散材スラリーの体積（ｍｌ）である。）
で算出することができる。 In this medium stirring type dispersing apparatus, the ultimate dispersed particle diameter and the dispersion time depend on the number N of medium particles per slurry volume made of the material to be dispersed.
Here, the number N of medium particles is expressed by the following formula (1).

(Where Vm is the apparent volume (cm ³ ) of the medium particles, Dm is the diameter (cm) of the medium particles, and Vs is the volume (ml) of the slurry to be dispersed.)
Can be calculated.

  Examples of the medium particles include glass beads, alumina beads, zirconia beads, zircon beads, and titania beads. The diameter of the medium particles is not particularly limited as long as the number of media per unit volume of the electrode forming slurry can be obtained. If the diameter of the medium particles is small, the number of medium particles can be increased with a smaller amount of medium particles used. Therefore, it can be said that the smaller the particle diameter of the medium, the better.

However, if the medium particle diameter is too small, the size of the surface area of the medium particles cannot be ignored, and the fluidity decreases. Therefore, in order to obtain the desired fluidity, it is necessary to increase the amount of the solvent. However, since the amount of the material to be dispersed, which is relatively solid, decreases, there arises a problem that the production efficiency is deteriorated. In addition, since the mass of one medium particle is reduced, the impact and resilience are reduced and the dispersion force is reduced.
Therefore, the diameter of the medium particles is preferably 10 μm or more and 1 mm or less in order to disperse the conductive additive to 500 nm or less.

Here, in order to know the relationship between the number N of medium particles and the dispersion time, a dispersion aid was used when dispersing carbon black having an average primary particle size of 14 nm and a specific surface area of 290 m ² / g in 1-methyl-2-pyrrolidone. When an alkylammonium salt of a high molecular weight copolymer having an amine value of 44 is used and zirconia beads, glass beads, and zircon are used as medium particles, the dispersion time and the number of medium particles N when carbon black reaches an average particle diameter of 500 nm The correlation with was investigated. The results are shown in FIG.
As shown in FIG. 1, it was found that when the ultimate dispersed particle diameter of the material to be dispersed is 500 nm, the number of medium particles N in the medium stirring type dispersing apparatus needs to be 3500 or more.

The reason is that when the number N of the medium particles is 3500 or less, the dispersion does not proceed, the dispersion time is remarkably increased, and the ultimate dispersed particle diameter is also increased. Further, the upper limit of the number N of medium particles is not particularly limited. However, if the number is too large, the ratio of the material to be dispersed is decreased, and the production efficiency is deteriorated. Moreover, there is a concern that a large amount of impurities are mixed due to wear of the medium particles. Further, excessive energy for fluidizing the medium is required, which is not economically preferable.
As described above, it is important to obtain the optimum number of media by comprehensively considering the ultimate dispersed particle size, production efficiency, economy, and the like.

As a method for producing a slurry for forming an electrode using this medium stirring type dispersing device, usually, an electrode active material, a conductive additive, a dispersion improving agent, a binder and a solvent are mixed in advance and then dispersed by a medium stirring and dispersing device. The electrode active material and the conductive additive may be separately dispersed until a predetermined particle size is obtained, and then mixed.
When the electrode-forming slurry thus produced is used as a positive electrode agent for a lithium ion battery, a high-power battery can be produced with a smaller amount of conductive assistant.

EXAMPLES Hereinafter, although this invention is demonstrated concretely by Examples 1-4 and Comparative Examples 1-3, this invention is not limited by these Examples.
For example, in this embodiment, metal Li is used for the negative electrode in order to reflect the behavior of the electrode material itself in the data. However, a negative electrode material such as a carbon material, a Li alloy, or Li ₄ Ti ₅ O ₁₂ may be used. . A solid electrolyte may be used instead of the electrolytic solution and the separator.

"Example 1"
25 parts by weight of carbon black (CB) having an average primary particle size of 14 nm and a specific surface area of 290 m ² / g, 3.75 parts by weight of an alkyl ammonium salt of a high molecular weight copolymer having an amine number of 44 as a dispersion improver, 1-methyl 2-pyrrolidone (NMP) 71.25 parts by weight were mixed to obtain a mixture having a volume of 87 ml. A CB slurry was obtained by using 87 cm ³ of zirconia beads having a diameter of 0.25 mm as medium particles for this mixture and dispersing at a disk rotating peripheral speed of 10 m / sec for 2 hours using a sand mill.
At this time, the number N of medium particles of zirconia beads was about 81500 particles / ml per CB slurry volume. Moreover, it was 202 nm when the average particle diameter of this CB slurry was measured by the laser diffraction scattering method.

Next, 40 parts by weight of this CB slurry, 85 parts by weight of LiFePO ₄ as a positive electrode active material, 5 parts by weight of polyvinylidene fluoride (PVdF), 1-methyl 2-pyrrolidone (NMP) as a solvent, Mixing so that the concentration is 45% by weight, using 87 cm ³ of zirconia beads having a diameter of 0.25 mm, mixing using a sand mill at a disc rotating peripheral speed of 7.5 m / sec for 15 minutes, A positive electrode active material slurry was obtained.

"Example 2"
A CB slurry was obtained in the same manner as in Example 1 except that 130 cm ³ of zirconia beads having a diameter of 0.6 mm were used as medium particles. At this time, the number N of medium particles of zirconia beads was about 8800 particles / ml per CB slurry volume. It was 460 nm when the average particle diameter of this CB slurry was measured by the laser diffraction scattering method.
Next, using this CB slurry, a positive electrode active material slurry was produced in the same manner as in Example 1.

"Example 3"
A CB slurry was obtained in the same manner as in Example 1 except that 65 cm ³ of zirconia beads having a diameter of 0.6 mm were used as medium particles. At this time, the number of medium particles N of zirconia beads was about 4400 particles / ml per CB slurry volume. It was 913 nm when the average particle diameter of this CB slurry was measured by the laser diffraction scattering method. Furthermore, when it was dispersed until the average particle size reached 500 nm, it took 18 hours for dispersion.
Next, using this CB slurry, a positive electrode active material slurry was produced in the same manner as in Example 1.

Example 4
Example 1 except that 87 cm ³ of glass beads having a diameter of 0.1 mm were used as the medium particles and 2-stearyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine was used as the dispersion aid. A CB slurry was obtained. At this time, the number N of medium particles of the glass beads was about 1274000 particles / ml per CB slurry volume. It was 96 nm when the average particle diameter of this CB slurry was measured by the laser diffraction scattering method.
Next, using this CB slurry, a positive electrode active material slurry was produced in the same manner as in Example 1.

"Comparative Example 1"
A CB slurry was obtained in the same manner as in Example 1 except that 43 cm ³ of zirconia beads having a diameter of 0.6 mm were used as medium particles. At this time, the number of medium particles N of zirconia beads was about 3000 particles / ml per CB slurry volume. It was 1050 nm when the average particle diameter of this CB slurry was measured by the laser diffraction scattering method. Furthermore, when the dispersion time was extended, the average particle size did not reach 500 nm.
Next, using this CB slurry, a positive electrode active material slurry was produced in the same manner as in Example 1.

"Comparative Example 2"
A CB slurry was obtained in the same manner as in Example 1 except that 174 cm ³ of zirconia beads having a diameter of 1.0 mm were used as medium particles. At this time, the number of medium particles N of zirconia beads was about 2500 / ml per CB slurry volume. It was 956 nm when the average particle diameter of this CB slurry was measured by the laser diffraction scattering method. Furthermore, when the dispersion time was extended, the average particle size did not reach 500 nm.
Next, using this CB slurry, a positive electrode active material slurry was produced in the same manner as in Example 1.

“Comparative Example 3”
120 parts by weight of the CB slurry prepared in Comparative Example 1, 85 parts by weight of LiFePO ₄ as a positive electrode active material, 5 parts by weight of polyvinylidene fluoride (PVdF), and 1-methyl 2-pyrrolidone (NMP) as a solvent. And mixed so that the solid content concentration becomes 45% by weight, and then using 43 cm ³ of zirconia beads having a diameter of 0.6 mm, and using a sand mill at a disc rotating peripheral speed of 7.5 m / sec. Mixing was performed for 15 minutes to obtain a positive electrode active material slurry.
In this positive electrode active material slurry, three times as much carbon black as in Examples 1 to 3 and Comparative Examples 1 and 2 was mixed.

“Production of lithium-ion batteries”
The positive electrode active material slurry obtained in Example 1 was applied onto an aluminum (Al) foil having a thickness of 30 μm, then vacuum-dried using a vacuum dryer, and then pressure-bonded to form a positive electrode (positive electrode ).
Subsequently, the lithium ion battery of Example 1 was produced using the 2016 coin type cell made from stainless steel (SUS) in dry Ar atmosphere.
Metal Li was used for the negative electrode, a porous polypropylene film was used for the separator, and a 1 mol / L LiPF ₆ solution was used for the electrolyte solution. As a solvent for this LiPF ₆ solution, a solvent having a ratio of ethylene carbonate to diethyl carbonate of 1: 1 was used.

  Further, using the CB slurries of Examples 2 to 4 and Comparative Examples 1 to 3, respectively, the lithium ion batteries of Examples 2 to 4 and Comparative Examples 1 to 3 were produced in exactly the same manner as the lithium ion battery of Example 1. did.

"Battery charge / discharge test"
The charge / discharge test of each of the lithium ion batteries of Examples 1 to 4 and Comparative Examples 1 to 3 was performed.
Here, the cut-off voltage was 2 to 4.5 V, the current value of the charge / discharge rate 1C was two types of 0.2C and 5C, and the environmental temperature of the test was 25 ° C. (room temperature).
The charge / discharge test results of the lithium ion batteries of Examples 1 to 4 and Comparative Examples 1 to 3 are shown in Table 1 together with the type of medium particles and the number of medium particles.
Here, the ratio of the discharge capacity at 5C to the discharge capacity at 0.2C was defined as output performance.

  According to the above results, in the lithium ion batteries of Examples 1 to 4, both the discharge capacity at 0.2C, the discharge capacity at 5C, and the output performance are superior to the lithium ion batteries of Comparative Examples 1 to 3. It was found that high output can be achieved while maintaining high energy density.

  Since the slurry for electrode formation of the lithium ion battery of the present invention contains an electrode active material, a conductive assistant, a binder and a polar solvent, and the average particle diameter when the conductive assistant is dispersed is 500 nm or less. In addition to being able to achieve high output while maintaining the high energy density that is characteristic of lithium-ion batteries, power sources for mobile vehicles such as electric vehicles and hybrid vehicles, or load leveling of power generation equipment It is also possible to apply to such fields, and the effect is very large.

It is a figure which shows the correlation with the dispersion time and medium particle number N which carbon black reached to 500 nm by average particle diameter.

Claims (6)

A slurry for forming an electrode of a lithium ion battery comprising an electrode active material, a conductive additive, a binder and a polar solvent,
The slurry for forming an electrode of a lithium ion battery, wherein an average particle diameter when the conductive assistant is dispersed is 500 nm or less.   The slurry for forming an electrode of a lithium ion battery according to claim 1, further comprising a dispersion improver.   3. The dispersion improver is one selected from the group consisting of an amino group-containing organic acid, an amino group-containing organic acid salt, an imino group-containing organic acid, and an imino group-containing organic acid salt. Slurry for forming electrodes of lithium ion batteries.   4. The slurry for forming an electrode of a lithium ion battery according to claim 2, wherein the dispersion improver has an amine value of 15 or more. A method for producing a slurry for forming an electrode of a lithium ion battery according to any one of claims 1 to 4,
When the electrode active material, the conductive additive, the binder, and the polar solvent are stirred and dispersed together with the medium particles to form a slurry, the number of the medium particles in 1 ml of the slurry is 3500 or more. The manufacturing method of the slurry for electrode formation of a lithium ion battery.   5. A lithium ion battery comprising a positive electrode using the electrode forming slurry for a lithium ion battery according to claim 1.

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